spi-pl022:starfive:Add spi driver for StarFive SoC platform
authorxingyu.wu <xingyu.wu@starfivetech.com>
Thu, 30 Jun 2022 06:45:38 +0000 (14:45 +0800)
committerxingyu.wu <xingyu.wu@starfivetech.com>
Thu, 30 Jun 2022 07:12:27 +0000 (15:12 +0800)
Modified based on spi-pl022.c

Signed-off-by: Xingyu Wu <xingyu.wu@starfivetech.com>
drivers/spi/Kconfig [changed mode: 0644->0755]
drivers/spi/Makefile [changed mode: 0644->0755]
drivers/spi/spi-pl022-starfive.c [new file with mode: 0755]

old mode 100644 (file)
new mode 100755 (executable)
index 83e352b..ed15861
@@ -628,6 +628,14 @@ config SPI_PL022
          controller. If you have an embedded system with an AMBA(R)
          bus and a PL022 controller, say Y or M here.
 
+config SPI_PL022_STARFIVE
+       tristate "ARM AMBA PL022 SSP controller on StarFive SoC platform"
+       depends on ARM_AMBA && SOC_STARFIVE
+       default n if SPI_PL022
+       help
+         Say 'Y' or 'M' here if you are building for StarFive SoCs platforms
+         that contain AMBA(R) PrimeCell PL022 SSP controller core. 
+
 config SPI_PPC4xx
        tristate "PPC4xx SPI Controller"
        depends on PPC32 && 4xx
old mode 100644 (file)
new mode 100755 (executable)
index 699db95..1aeda20
@@ -87,6 +87,7 @@ obj-$(CONFIG_SPI_ORION)                       += spi-orion.o
 obj-$(CONFIG_SPI_PIC32)                        += spi-pic32.o
 obj-$(CONFIG_SPI_PIC32_SQI)            += spi-pic32-sqi.o
 obj-$(CONFIG_SPI_PL022)                        += spi-pl022.o
+obj-$(CONFIG_SPI_PL022_STARFIVE)       += spi-pl022-starfive.o
 obj-$(CONFIG_SPI_PPC4xx)               += spi-ppc4xx.o
 spi-pxa2xx-platform-objs               := spi-pxa2xx.o spi-pxa2xx-dma.o
 obj-$(CONFIG_SPI_PXA2XX)               += spi-pxa2xx-platform.o
diff --git a/drivers/spi/spi-pl022-starfive.c b/drivers/spi/spi-pl022-starfive.c
new file mode 100755 (executable)
index 0000000..d195061
--- /dev/null
@@ -0,0 +1,2472 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * A driver for the ARM PL022 PrimeCell SSP/SPI bus master.
+ *
+ * Copyright (C) 2008-2012 ST-Ericsson AB
+ * Copyright (C) 2006 STMicroelectronics Pvt. Ltd.
+ *
+ * Author: Linus Walleij <linus.walleij@stericsson.com>
+ *
+ * Initial version inspired by:
+ *     linux-2.6.17-rc3-mm1/drivers/spi/pxa2xx_spi.c
+ * Initial adoption to PL022 by:
+ *      Sachin Verma <sachin.verma@st.com>
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/ioport.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/spi/spi.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/amba/bus.h>
+#include <linux/amba/pl022.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/scatterlist.h>
+#include <linux/pm_runtime.h>
+#include <linux/of.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/reset.h>
+
+/*
+ * This macro is used to define some register default values.
+ * reg is masked with mask, the OR:ed with an (again masked)
+ * val shifted sb steps to the left.
+ */
+#define SSP_WRITE_BITS(reg, val, mask, sb) \
+ ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask))))
+
+/*
+ * This macro is also used to define some default values.
+ * It will just shift val by sb steps to the left and mask
+ * the result with mask.
+ */
+#define GEN_MASK_BITS(val, mask, sb) \
+ (((val)<<(sb)) & (mask))
+
+#define DRIVE_TX               0
+#define DO_NOT_DRIVE_TX                1
+
+#define DO_NOT_QUEUE_DMA       0
+#define QUEUE_DMA              1
+
+#define RX_TRANSFER            1
+#define TX_TRANSFER            2
+
+/*
+ * Macros to access SSP Registers with their offsets
+ */
+#define SSP_CR0(r)     (r + 0x000)
+#define SSP_CR1(r)     (r + 0x004)
+#define SSP_DR(r)      (r + 0x008)
+#define SSP_SR(r)      (r + 0x00C)
+#define SSP_CPSR(r)    (r + 0x010)
+#define SSP_IMSC(r)    (r + 0x014)
+#define SSP_RIS(r)     (r + 0x018)
+#define SSP_MIS(r)     (r + 0x01C)
+#define SSP_ICR(r)     (r + 0x020)
+#define SSP_DMACR(r)   (r + 0x024)
+#define SSP_CSR(r)     (r + 0x030) /* vendor extension */
+#define SSP_ITCR(r)    (r + 0x080)
+#define SSP_ITIP(r)    (r + 0x084)
+#define SSP_ITOP(r)    (r + 0x088)
+#define SSP_TDR(r)     (r + 0x08C)
+
+#define SSP_PID0(r)    (r + 0xFE0)
+#define SSP_PID1(r)    (r + 0xFE4)
+#define SSP_PID2(r)    (r + 0xFE8)
+#define SSP_PID3(r)    (r + 0xFEC)
+
+#define SSP_CID0(r)    (r + 0xFF0)
+#define SSP_CID1(r)    (r + 0xFF4)
+#define SSP_CID2(r)    (r + 0xFF8)
+#define SSP_CID3(r)    (r + 0xFFC)
+
+/*
+ * SSP Control Register 0  - SSP_CR0
+ */
+#define SSP_CR0_MASK_DSS       (0x0FUL << 0)
+#define SSP_CR0_MASK_FRF       (0x3UL << 4)
+#define SSP_CR0_MASK_SPO       (0x1UL << 6)
+#define SSP_CR0_MASK_SPH       (0x1UL << 7)
+#define SSP_CR0_MASK_SCR       (0xFFUL << 8)
+
+/*
+ * The ST version of this block moves som bits
+ * in SSP_CR0 and extends it to 32 bits
+ */
+#define SSP_CR0_MASK_DSS_ST    (0x1FUL << 0)
+#define SSP_CR0_MASK_HALFDUP_ST        (0x1UL << 5)
+#define SSP_CR0_MASK_CSS_ST    (0x1FUL << 16)
+#define SSP_CR0_MASK_FRF_ST    (0x3UL << 21)
+
+/*
+ * SSP Control Register 0  - SSP_CR1
+ */
+#define SSP_CR1_MASK_LBM       (0x1UL << 0)
+#define SSP_CR1_MASK_SSE       (0x1UL << 1)
+#define SSP_CR1_MASK_MS                (0x1UL << 2)
+#define SSP_CR1_MASK_SOD       (0x1UL << 3)
+
+/*
+ * The ST version of this block adds some bits
+ * in SSP_CR1
+ */
+#define SSP_CR1_MASK_RENDN_ST  (0x1UL << 4)
+#define SSP_CR1_MASK_TENDN_ST  (0x1UL << 5)
+#define SSP_CR1_MASK_MWAIT_ST  (0x1UL << 6)
+#define SSP_CR1_MASK_RXIFLSEL_ST (0x7UL << 7)
+#define SSP_CR1_MASK_TXIFLSEL_ST (0x7UL << 10)
+/* This one is only in the PL023 variant */
+#define SSP_CR1_MASK_FBCLKDEL_ST (0x7UL << 13)
+
+/*
+ * SSP Status Register - SSP_SR
+ */
+#define SSP_SR_MASK_TFE                (0x1UL << 0) /* Transmit FIFO empty */
+#define SSP_SR_MASK_TNF                (0x1UL << 1) /* Transmit FIFO not full */
+#define SSP_SR_MASK_RNE                (0x1UL << 2) /* Receive FIFO not empty */
+#define SSP_SR_MASK_RFF                (0x1UL << 3) /* Receive FIFO full */
+#define SSP_SR_MASK_BSY                (0x1UL << 4) /* Busy Flag */
+
+/*
+ * SSP Clock Prescale Register  - SSP_CPSR
+ */
+#define SSP_CPSR_MASK_CPSDVSR  (0xFFUL << 0)
+
+/*
+ * SSP Interrupt Mask Set/Clear Register - SSP_IMSC
+ */
+#define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */
+#define SSP_IMSC_MASK_RTIM  (0x1UL << 1) /* Receive timeout Interrupt mask */
+#define SSP_IMSC_MASK_RXIM  (0x1UL << 2) /* Receive FIFO Interrupt mask */
+#define SSP_IMSC_MASK_TXIM  (0x1UL << 3) /* Transmit FIFO Interrupt mask */
+
+/*
+ * SSP Raw Interrupt Status Register - SSP_RIS
+ */
+/* Receive Overrun Raw Interrupt status */
+#define SSP_RIS_MASK_RORRIS            (0x1UL << 0)
+/* Receive Timeout Raw Interrupt status */
+#define SSP_RIS_MASK_RTRIS             (0x1UL << 1)
+/* Receive FIFO Raw Interrupt status */
+#define SSP_RIS_MASK_RXRIS             (0x1UL << 2)
+/* Transmit FIFO Raw Interrupt status */
+#define SSP_RIS_MASK_TXRIS             (0x1UL << 3)
+
+/*
+ * SSP Masked Interrupt Status Register - SSP_MIS
+ */
+/* Receive Overrun Masked Interrupt status */
+#define SSP_MIS_MASK_RORMIS            (0x1UL << 0)
+/* Receive Timeout Masked Interrupt status */
+#define SSP_MIS_MASK_RTMIS             (0x1UL << 1)
+/* Receive FIFO Masked Interrupt status */
+#define SSP_MIS_MASK_RXMIS             (0x1UL << 2)
+/* Transmit FIFO Masked Interrupt status */
+#define SSP_MIS_MASK_TXMIS             (0x1UL << 3)
+
+/*
+ * SSP Interrupt Clear Register - SSP_ICR
+ */
+/* Receive Overrun Raw Clear Interrupt bit */
+#define SSP_ICR_MASK_RORIC             (0x1UL << 0)
+/* Receive Timeout Clear Interrupt bit */
+#define SSP_ICR_MASK_RTIC              (0x1UL << 1)
+
+/*
+ * SSP DMA Control Register - SSP_DMACR
+ */
+/* Receive DMA Enable bit */
+#define SSP_DMACR_MASK_RXDMAE          (0x1UL << 0)
+/* Transmit DMA Enable bit */
+#define SSP_DMACR_MASK_TXDMAE          (0x1UL << 1)
+
+/*
+ * SSP Chip Select Control Register - SSP_CSR
+ * (vendor extension)
+ */
+#define SSP_CSR_CSVALUE_MASK           (0x1FUL << 0)
+
+/*
+ * SSP Integration Test control Register - SSP_ITCR
+ */
+#define SSP_ITCR_MASK_ITEN             (0x1UL << 0)
+#define SSP_ITCR_MASK_TESTFIFO         (0x1UL << 1)
+
+/*
+ * SSP Integration Test Input Register - SSP_ITIP
+ */
+#define ITIP_MASK_SSPRXD                (0x1UL << 0)
+#define ITIP_MASK_SSPFSSIN              (0x1UL << 1)
+#define ITIP_MASK_SSPCLKIN              (0x1UL << 2)
+#define ITIP_MASK_RXDMAC                (0x1UL << 3)
+#define ITIP_MASK_TXDMAC                (0x1UL << 4)
+#define ITIP_MASK_SSPTXDIN              (0x1UL << 5)
+
+/*
+ * SSP Integration Test output Register - SSP_ITOP
+ */
+#define ITOP_MASK_SSPTXD                (0x1UL << 0)
+#define ITOP_MASK_SSPFSSOUT             (0x1UL << 1)
+#define ITOP_MASK_SSPCLKOUT             (0x1UL << 2)
+#define ITOP_MASK_SSPOEn                (0x1UL << 3)
+#define ITOP_MASK_SSPCTLOEn             (0x1UL << 4)
+#define ITOP_MASK_RORINTR               (0x1UL << 5)
+#define ITOP_MASK_RTINTR                (0x1UL << 6)
+#define ITOP_MASK_RXINTR                (0x1UL << 7)
+#define ITOP_MASK_TXINTR                (0x1UL << 8)
+#define ITOP_MASK_INTR                  (0x1UL << 9)
+#define ITOP_MASK_RXDMABREQ             (0x1UL << 10)
+#define ITOP_MASK_RXDMASREQ             (0x1UL << 11)
+#define ITOP_MASK_TXDMABREQ             (0x1UL << 12)
+#define ITOP_MASK_TXDMASREQ             (0x1UL << 13)
+
+/*
+ * SSP Test Data Register - SSP_TDR
+ */
+#define TDR_MASK_TESTDATA              (0xFFFFFFFF)
+
+/*
+ * Message State
+ * we use the spi_message.state (void *) pointer to
+ * hold a single state value, that's why all this
+ * (void *) casting is done here.
+ */
+#define STATE_START                    ((void *) 0)
+#define STATE_RUNNING                  ((void *) 1)
+#define STATE_DONE                     ((void *) 2)
+#define STATE_ERROR                    ((void *) -1)
+#define STATE_TIMEOUT                  ((void *) -2)
+
+/*
+ * SSP State - Whether Enabled or Disabled
+ */
+#define SSP_DISABLED                   (0)
+#define SSP_ENABLED                    (1)
+
+/*
+ * SSP DMA State - Whether DMA Enabled or Disabled
+ */
+#define SSP_DMA_DISABLED               (0)
+#define SSP_DMA_ENABLED                        (1)
+
+/*
+ * SSP Clock Defaults
+ */
+#define SSP_DEFAULT_CLKRATE 0x2
+#define SSP_DEFAULT_PRESCALE 0x40
+
+/*
+ * SSP Clock Parameter ranges
+ */
+#define CPSDVR_MIN 0x02
+#define CPSDVR_MAX 0xFE
+#define SCR_MIN 0x00
+#define SCR_MAX 0xFF
+
+/*
+ * SSP Interrupt related Macros
+ */
+#define DEFAULT_SSP_REG_IMSC  0x0UL
+#define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC
+#define ENABLE_ALL_INTERRUPTS ( \
+       SSP_IMSC_MASK_RORIM | \
+       SSP_IMSC_MASK_RTIM | \
+       SSP_IMSC_MASK_RXIM | \
+       SSP_IMSC_MASK_TXIM \
+)
+
+#define CLEAR_ALL_INTERRUPTS  0x3
+
+#define SPI_POLLING_TIMEOUT 1000
+
+/*
+ * The type of reading going on this chip
+ */
+enum ssp_reading {
+       READING_NULL,
+       READING_U8,
+       READING_U16,
+       READING_U32
+};
+
+/*
+ * The type of writing going on this chip
+ */
+enum ssp_writing {
+       WRITING_NULL,
+       WRITING_U8,
+       WRITING_U16,
+       WRITING_U32
+};
+
+/**
+ * struct vendor_data - vendor-specific config parameters
+ * for PL022 derivates
+ * @fifodepth: depth of FIFOs (both)
+ * @max_bpw: maximum number of bits per word
+ * @unidir: supports unidirection transfers
+ * @extended_cr: 32 bit wide control register 0 with extra
+ * features and extra features in CR1 as found in the ST variants
+ * @pl023: supports a subset of the ST extensions called "PL023"
+ * @loopback: supports loopback mode
+ * @internal_cs_ctrl: supports chip select control register
+ */
+struct vendor_data {
+       int fifodepth;
+       int max_bpw;
+       bool unidir;
+       bool extended_cr;
+       bool pl023;
+       bool loopback;
+       bool internal_cs_ctrl;
+};
+
+/**
+ * struct pl022 - This is the private SSP driver data structure
+ * @adev: AMBA device model hookup
+ * @vendor: vendor data for the IP block
+ * @phybase: the physical memory where the SSP device resides
+ * @virtbase: the virtual memory where the SSP is mapped
+ * @clk: outgoing clock "SPICLK" for the SPI bus
+ * @master: SPI framework hookup
+ * @master_info: controller-specific data from machine setup
+ * @pump_transfers: Tasklet used in Interrupt Transfer mode
+ * @cur_msg: Pointer to current spi_message being processed
+ * @cur_transfer: Pointer to current spi_transfer
+ * @cur_chip: pointer to current clients chip(assigned from controller_state)
+ * @next_msg_cs_active: the next message in the queue has been examined
+ *  and it was found that it uses the same chip select as the previous
+ *  message, so we left it active after the previous transfer, and it's
+ *  active already.
+ * @tx: current position in TX buffer to be read
+ * @tx_end: end position in TX buffer to be read
+ * @rx: current position in RX buffer to be written
+ * @rx_end: end position in RX buffer to be written
+ * @read: the type of read currently going on
+ * @write: the type of write currently going on
+ * @exp_fifo_level: expected FIFO level
+ * @rx_lev_trig: receive FIFO watermark level which triggers IRQ
+ * @tx_lev_trig: transmit FIFO watermark level which triggers IRQ
+ * @dma_rx_channel: optional channel for RX DMA
+ * @dma_tx_channel: optional channel for TX DMA
+ * @sgt_rx: scattertable for the RX transfer
+ * @sgt_tx: scattertable for the TX transfer
+ * @dummypage: a dummy page used for driving data on the bus with DMA
+ * @dma_running: indicates whether DMA is in operation
+ * @cur_cs: current chip select index
+ * @cur_gpiod: current chip select GPIO descriptor
+ */
+struct pl022 {
+       struct amba_device              *adev;
+       struct vendor_data              *vendor;
+       resource_size_t                 phybase;
+       void __iomem                    *virtbase;
+       struct clk                      *clk;
+       struct reset_control    *rst;
+       struct spi_master               *master;
+       struct pl022_ssp_controller     *master_info;
+       /* Message per-transfer pump */
+       struct tasklet_struct           pump_transfers;
+       struct spi_message              *cur_msg;
+       struct spi_transfer             *cur_transfer;
+       struct chip_data                *cur_chip;
+       bool                            next_msg_cs_active;
+       void                            *tx;
+       void                            *tx_end;
+       void                            *rx;
+       void                            *rx_end;
+       enum ssp_reading                read;
+       enum ssp_writing                write;
+       u32                             exp_fifo_level;
+       enum ssp_rx_level_trig          rx_lev_trig;
+       enum ssp_tx_level_trig          tx_lev_trig;
+       /* DMA settings */
+#ifdef CONFIG_DMA_ENGINE
+       struct dma_chan                 *dma_rx_channel;
+       struct dma_chan                 *dma_tx_channel;
+       struct sg_table                 sgt_rx;
+       struct sg_table                 sgt_tx;
+       char                            *dummypage;
+       bool                            dma_running;
+#endif
+       int cur_cs;
+       struct gpio_desc *cur_gpiod;
+};
+
+/**
+ * struct chip_data - To maintain runtime state of SSP for each client chip
+ * @cr0: Value of control register CR0 of SSP - on later ST variants this
+ *       register is 32 bits wide rather than just 16
+ * @cr1: Value of control register CR1 of SSP
+ * @dmacr: Value of DMA control Register of SSP
+ * @cpsr: Value of Clock prescale register
+ * @n_bytes: how many bytes(power of 2) reqd for a given data width of client
+ * @enable_dma: Whether to enable DMA or not
+ * @read: function ptr to be used to read when doing xfer for this chip
+ * @write: function ptr to be used to write when doing xfer for this chip
+ * @xfer_type: polling/interrupt/DMA
+ *
+ * Runtime state of the SSP controller, maintained per chip,
+ * This would be set according to the current message that would be served
+ */
+struct chip_data {
+       u32 cr0;
+       u16 cr1;
+       u16 dmacr;
+       u16 cpsr;
+       u8 n_bytes;
+       bool enable_dma;
+       enum ssp_reading read;
+       enum ssp_writing write;
+       int xfer_type;
+};
+
+/**
+ * internal_cs_control - Control chip select signals via SSP_CSR.
+ * @pl022: SSP driver private data structure
+ * @command: select/delect the chip
+ *
+ * Used on controller with internal chip select control via SSP_CSR register
+ * (vendor extension). Each of the 5 LSB in the register controls one chip
+ * select signal.
+ */
+static void internal_cs_control(struct pl022 *pl022, u32 command)
+{
+       u32 tmp;
+
+       tmp = readw(SSP_CSR(pl022->virtbase));
+       if (command == SSP_CHIP_SELECT)
+               tmp &= ~BIT(pl022->cur_cs);
+       else
+               tmp |= BIT(pl022->cur_cs);
+       writew(tmp, SSP_CSR(pl022->virtbase));
+}
+
+static void pl022_cs_control(struct pl022 *pl022, u32 command)
+{
+       if (pl022->vendor->internal_cs_ctrl)
+               internal_cs_control(pl022, command);
+       else if (pl022->cur_gpiod)
+               /*
+                * This needs to be inverted since with GPIOLIB in
+                * control, the inversion will be handled by
+                * GPIOLIB's active low handling. The "command"
+                * passed into this function will be SSP_CHIP_SELECT
+                * which is enum:ed to 0, so we need the inverse
+                * (1) to activate chip select.
+                */
+               gpiod_set_value(pl022->cur_gpiod, !command);
+}
+
+/**
+ * giveback - current spi_message is over, schedule next message and call
+ * callback of this message. Assumes that caller already
+ * set message->status; dma and pio irqs are blocked
+ * @pl022: SSP driver private data structure
+ */
+static void giveback(struct pl022 *pl022)
+{
+       struct spi_transfer *last_transfer;
+       pl022->next_msg_cs_active = false;
+
+       last_transfer = list_last_entry(&pl022->cur_msg->transfers,
+                                       struct spi_transfer, transfer_list);
+
+       /* Delay if requested before any change in chip select */
+       /*
+        * FIXME: This runs in interrupt context.
+        * Is this really smart?
+        */
+       spi_transfer_delay_exec(last_transfer);
+
+       if (!last_transfer->cs_change) {
+               struct spi_message *next_msg;
+
+               /*
+                * cs_change was not set. We can keep the chip select
+                * enabled if there is message in the queue and it is
+                * for the same spi device.
+                *
+                * We cannot postpone this until pump_messages, because
+                * after calling msg->complete (below) the driver that
+                * sent the current message could be unloaded, which
+                * could invalidate the cs_control() callback...
+                */
+               /* get a pointer to the next message, if any */
+               next_msg = spi_get_next_queued_message(pl022->master);
+
+               /*
+                * see if the next and current messages point
+                * to the same spi device.
+                */
+               if (next_msg && next_msg->spi != pl022->cur_msg->spi)
+                       next_msg = NULL;
+               if (!next_msg || pl022->cur_msg->state == STATE_ERROR)
+                       pl022_cs_control(pl022, SSP_CHIP_DESELECT);
+               else
+                       pl022->next_msg_cs_active = true;
+
+       }
+
+       pl022->cur_msg = NULL;
+       pl022->cur_transfer = NULL;
+       pl022->cur_chip = NULL;
+
+       /* disable the SPI/SSP operation */
+       writew((readw(SSP_CR1(pl022->virtbase)) &
+               (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
+
+       spi_finalize_current_message(pl022->master);
+}
+
+/**
+ * flush - flush the FIFO to reach a clean state
+ * @pl022: SSP driver private data structure
+ */
+static int flush(struct pl022 *pl022)
+{
+       unsigned long limit = loops_per_jiffy << 1;
+
+       dev_dbg(&pl022->adev->dev, "flush\n");
+       do {
+               while (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
+                       readw(SSP_DR(pl022->virtbase));
+       } while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_BSY) && limit--);
+
+       pl022->exp_fifo_level = 0;
+
+       return limit;
+}
+
+/**
+ * restore_state - Load configuration of current chip
+ * @pl022: SSP driver private data structure
+ */
+static void restore_state(struct pl022 *pl022)
+{
+       struct chip_data *chip = pl022->cur_chip;
+
+       if (pl022->vendor->extended_cr)
+               writel(chip->cr0, SSP_CR0(pl022->virtbase));
+       else
+               writew(chip->cr0, SSP_CR0(pl022->virtbase));
+       writew(chip->cr1, SSP_CR1(pl022->virtbase));
+       writew(chip->dmacr, SSP_DMACR(pl022->virtbase));
+       writew(chip->cpsr, SSP_CPSR(pl022->virtbase));
+       writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
+       writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
+}
+
+/*
+ * Default SSP Register Values
+ */
+#define DEFAULT_SSP_REG_CR0 ( \
+       GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0)    | \
+       GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 4) | \
+       GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
+       GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
+       GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
+)
+
+/* ST versions have slightly different bit layout */
+#define DEFAULT_SSP_REG_CR0_ST ( \
+       GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
+       GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP_ST, 5) | \
+       GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
+       GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
+       GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \
+       GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS_ST, 16)      | \
+       GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF_ST, 21) \
+)
+
+/* The PL023 version is slightly different again */
+#define DEFAULT_SSP_REG_CR0_ST_PL023 ( \
+       GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
+       GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
+       GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
+       GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
+)
+
+#define DEFAULT_SSP_REG_CR1 ( \
+       GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \
+       GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
+       GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
+       GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) \
+)
+
+/* ST versions extend this register to use all 16 bits */
+#define DEFAULT_SSP_REG_CR1_ST ( \
+       DEFAULT_SSP_REG_CR1 | \
+       GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
+       GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
+       GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT_ST, 6) |\
+       GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
+       GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) \
+)
+
+/*
+ * The PL023 variant has further differences: no loopback mode, no microwire
+ * support, and a new clock feedback delay setting.
+ */
+#define DEFAULT_SSP_REG_CR1_ST_PL023 ( \
+       GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
+       GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
+       GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \
+       GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
+       GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
+       GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
+       GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) | \
+       GEN_MASK_BITS(SSP_FEEDBACK_CLK_DELAY_NONE, SSP_CR1_MASK_FBCLKDEL_ST, 13) \
+)
+
+#define DEFAULT_SSP_REG_CPSR ( \
+       GEN_MASK_BITS(SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \
+)
+
+#define DEFAULT_SSP_REG_DMACR (\
+       GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \
+       GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \
+)
+
+/**
+ * load_ssp_default_config - Load default configuration for SSP
+ * @pl022: SSP driver private data structure
+ */
+static void load_ssp_default_config(struct pl022 *pl022)
+{
+       if (pl022->vendor->pl023) {
+               writel(DEFAULT_SSP_REG_CR0_ST_PL023, SSP_CR0(pl022->virtbase));
+               writew(DEFAULT_SSP_REG_CR1_ST_PL023, SSP_CR1(pl022->virtbase));
+       } else if (pl022->vendor->extended_cr) {
+               writel(DEFAULT_SSP_REG_CR0_ST, SSP_CR0(pl022->virtbase));
+               writew(DEFAULT_SSP_REG_CR1_ST, SSP_CR1(pl022->virtbase));
+       } else {
+               writew(DEFAULT_SSP_REG_CR0, SSP_CR0(pl022->virtbase));
+               writew(DEFAULT_SSP_REG_CR1, SSP_CR1(pl022->virtbase));
+       }
+       writew(DEFAULT_SSP_REG_DMACR, SSP_DMACR(pl022->virtbase));
+       writew(DEFAULT_SSP_REG_CPSR, SSP_CPSR(pl022->virtbase));
+       writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
+       writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
+}
+
+/*
+ * This will write to TX and read from RX according to the parameters
+ * set in pl022.
+ */
+static void readwriter(struct pl022 *pl022)
+{
+
+       /*
+        * The FIFO depth is different between primecell variants.
+        * I believe filling in too much in the FIFO might cause
+        * errons in 8bit wide transfers on ARM variants (just 8 words
+        * FIFO, means only 8x8 = 64 bits in FIFO) at least.
+        *
+        * To prevent this issue, the TX FIFO is only filled to the
+        * unused RX FIFO fill length, regardless of what the TX
+        * FIFO status flag indicates.
+        */
+       dev_dbg(&pl022->adev->dev,
+               "%s, rx: %p, rxend: %p, tx: %p, txend: %p\n",
+               __func__, pl022->rx, pl022->rx_end, pl022->tx, pl022->tx_end);
+
+       /* Read as much as you can */
+       while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
+              && (pl022->rx < pl022->rx_end)) {
+               switch (pl022->read) {
+               case READING_NULL:
+                       readw(SSP_DR(pl022->virtbase));
+                       break;
+               case READING_U8:
+                       *(u8 *) (pl022->rx) =
+                               readw(SSP_DR(pl022->virtbase)) & 0xFFU;
+                       break;
+               case READING_U16:
+                       *(u16 *) (pl022->rx) =
+                               (u16) readw(SSP_DR(pl022->virtbase));
+                       break;
+               case READING_U32:
+                       *(u32 *) (pl022->rx) =
+                               readl(SSP_DR(pl022->virtbase));
+                       break;
+               }
+               pl022->rx += (pl022->cur_chip->n_bytes);
+               pl022->exp_fifo_level--;
+       }
+       /*
+        * Write as much as possible up to the RX FIFO size
+        */
+       while ((pl022->exp_fifo_level < pl022->vendor->fifodepth)
+              && (pl022->tx < pl022->tx_end)) {
+               switch (pl022->write) {
+               case WRITING_NULL:
+                       writew(0x0, SSP_DR(pl022->virtbase));
+                       break;
+               case WRITING_U8:
+                       writew(*(u8 *) (pl022->tx), SSP_DR(pl022->virtbase));
+                       break;
+               case WRITING_U16:
+                       writew((*(u16 *) (pl022->tx)), SSP_DR(pl022->virtbase));
+                       break;
+               case WRITING_U32:
+                       writel(*(u32 *) (pl022->tx), SSP_DR(pl022->virtbase));
+                       break;
+               }
+               pl022->tx += (pl022->cur_chip->n_bytes);
+               pl022->exp_fifo_level++;
+               /*
+                * This inner reader takes care of things appearing in the RX
+                * FIFO as we're transmitting. This will happen a lot since the
+                * clock starts running when you put things into the TX FIFO,
+                * and then things are continuously clocked into the RX FIFO.
+                */
+               while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
+                      && (pl022->rx < pl022->rx_end)) {
+                       switch (pl022->read) {
+                       case READING_NULL:
+                               readw(SSP_DR(pl022->virtbase));
+                               break;
+                       case READING_U8:
+                               *(u8 *) (pl022->rx) =
+                                       readw(SSP_DR(pl022->virtbase)) & 0xFFU;
+                               break;
+                       case READING_U16:
+                               *(u16 *) (pl022->rx) =
+                                       (u16) readw(SSP_DR(pl022->virtbase));
+                               break;
+                       case READING_U32:
+                               *(u32 *) (pl022->rx) =
+                                       readl(SSP_DR(pl022->virtbase));
+                               break;
+                       }
+                       pl022->rx += (pl022->cur_chip->n_bytes);
+                       pl022->exp_fifo_level--;
+               }
+       }
+       /*
+        * When we exit here the TX FIFO should be full and the RX FIFO
+        * should be empty
+        */
+}
+
+/**
+ * next_transfer - Move to the Next transfer in the current spi message
+ * @pl022: SSP driver private data structure
+ *
+ * This function moves though the linked list of spi transfers in the
+ * current spi message and returns with the state of current spi
+ * message i.e whether its last transfer is done(STATE_DONE) or
+ * Next transfer is ready(STATE_RUNNING)
+ */
+static void *next_transfer(struct pl022 *pl022)
+{
+       struct spi_message *msg = pl022->cur_msg;
+       struct spi_transfer *trans = pl022->cur_transfer;
+
+       /* Move to next transfer */
+       if (trans->transfer_list.next != &msg->transfers) {
+               pl022->cur_transfer =
+                   list_entry(trans->transfer_list.next,
+                              struct spi_transfer, transfer_list);
+               return STATE_RUNNING;
+       }
+       return STATE_DONE;
+}
+
+/*
+ * This DMA functionality is only compiled in if we have
+ * access to the generic DMA devices/DMA engine.
+ */
+#ifdef CONFIG_DMA_ENGINE
+static void unmap_free_dma_scatter(struct pl022 *pl022)
+{
+       /* Unmap and free the SG tables */
+       dma_unmap_sg(pl022->dma_tx_channel->device->dev, pl022->sgt_tx.sgl,
+                    pl022->sgt_tx.nents, DMA_TO_DEVICE);
+       dma_unmap_sg(pl022->dma_rx_channel->device->dev, pl022->sgt_rx.sgl,
+                    pl022->sgt_rx.nents, DMA_FROM_DEVICE);
+       sg_free_table(&pl022->sgt_rx);
+       sg_free_table(&pl022->sgt_tx);
+}
+
+static void dma_callback(void *data)
+{
+       struct pl022 *pl022 = data;
+       struct spi_message *msg = pl022->cur_msg;
+
+       BUG_ON(!pl022->sgt_rx.sgl);
+
+#ifdef VERBOSE_DEBUG
+       /*
+        * Optionally dump out buffers to inspect contents, this is
+        * good if you want to convince yourself that the loopback
+        * read/write contents are the same, when adopting to a new
+        * DMA engine.
+        */
+       {
+               struct scatterlist *sg;
+               unsigned int i;
+
+               dma_sync_sg_for_cpu(&pl022->adev->dev,
+                                   pl022->sgt_rx.sgl,
+                                   pl022->sgt_rx.nents,
+                                   DMA_FROM_DEVICE);
+
+               for_each_sg(pl022->sgt_rx.sgl, sg, pl022->sgt_rx.nents, i) {
+                       dev_dbg(&pl022->adev->dev, "SPI RX SG ENTRY: %d", i);
+                       print_hex_dump(KERN_ERR, "SPI RX: ",
+                                      DUMP_PREFIX_OFFSET,
+                                      16,
+                                      1,
+                                      sg_virt(sg),
+                                      sg_dma_len(sg),
+                                      1);
+               }
+               for_each_sg(pl022->sgt_tx.sgl, sg, pl022->sgt_tx.nents, i) {
+                       dev_dbg(&pl022->adev->dev, "SPI TX SG ENTRY: %d", i);
+                       print_hex_dump(KERN_ERR, "SPI TX: ",
+                                      DUMP_PREFIX_OFFSET,
+                                      16,
+                                      1,
+                                      sg_virt(sg),
+                                      sg_dma_len(sg),
+                                      1);
+               }
+       }
+#endif
+
+       unmap_free_dma_scatter(pl022);
+
+       /* Update total bytes transferred */
+       msg->actual_length += pl022->cur_transfer->len;
+       /* Move to next transfer */
+       msg->state = next_transfer(pl022);
+       if (msg->state != STATE_DONE && pl022->cur_transfer->cs_change)
+               pl022_cs_control(pl022, SSP_CHIP_DESELECT);
+       tasklet_schedule(&pl022->pump_transfers);
+}
+
+static void setup_dma_scatter(struct pl022 *pl022,
+                             void *buffer,
+                             unsigned int length,
+                             struct sg_table *sgtab)
+{
+       struct scatterlist *sg;
+       int bytesleft = length;
+       void *bufp = buffer;
+       int mapbytes;
+       int i;
+
+       if (buffer) {
+               for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
+                       /*
+                        * If there are less bytes left than what fits
+                        * in the current page (plus page alignment offset)
+                        * we just feed in this, else we stuff in as much
+                        * as we can.
+                        */
+                       if (bytesleft < (PAGE_SIZE - offset_in_page(bufp)))
+                               mapbytes = bytesleft;
+                       else
+                               mapbytes = PAGE_SIZE - offset_in_page(bufp);
+                       sg_set_page(sg, virt_to_page(bufp),
+                                   mapbytes, offset_in_page(bufp));
+                       bufp += mapbytes;
+                       bytesleft -= mapbytes;
+                       dev_dbg(&pl022->adev->dev,
+                               "set RX/TX target page @ %p, %d bytes, %d left\n",
+                               bufp, mapbytes, bytesleft);
+               }
+       } else {
+               /* Map the dummy buffer on every page */
+               for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
+                       if (bytesleft < PAGE_SIZE)
+                               mapbytes = bytesleft;
+                       else
+                               mapbytes = PAGE_SIZE;
+                       sg_set_page(sg, virt_to_page(pl022->dummypage),
+                                   mapbytes, 0);
+                       bytesleft -= mapbytes;
+                       dev_dbg(&pl022->adev->dev,
+                               "set RX/TX to dummy page %d bytes, %d left\n",
+                               mapbytes, bytesleft);
+
+               }
+       }
+       BUG_ON(bytesleft);
+}
+
+/**
+ * configure_dma - configures the channels for the next transfer
+ * @pl022: SSP driver's private data structure
+ */
+static int configure_dma(struct pl022 *pl022)
+{
+       struct dma_slave_config rx_conf = {
+               .src_addr = SSP_DR(pl022->phybase),
+               .direction = DMA_DEV_TO_MEM,
+               .device_fc = false,
+       };
+       struct dma_slave_config tx_conf = {
+               .dst_addr = SSP_DR(pl022->phybase),
+               .direction = DMA_MEM_TO_DEV,
+               .device_fc = false,
+       };
+       unsigned int pages;
+       int ret;
+       int rx_sglen, tx_sglen;
+       struct dma_chan *rxchan = pl022->dma_rx_channel;
+       struct dma_chan *txchan = pl022->dma_tx_channel;
+       struct dma_async_tx_descriptor *rxdesc;
+       struct dma_async_tx_descriptor *txdesc;
+
+       /* Check that the channels are available */
+       if (!rxchan || !txchan)
+               return -ENODEV;
+
+       /*
+        * If supplied, the DMA burstsize should equal the FIFO trigger level.
+        * Notice that the DMA engine uses one-to-one mapping. Since we can
+        * not trigger on 2 elements this needs explicit mapping rather than
+        * calculation.
+        */
+       switch (pl022->rx_lev_trig) {
+       case SSP_RX_1_OR_MORE_ELEM:
+               rx_conf.src_maxburst = 1;
+               break;
+       case SSP_RX_4_OR_MORE_ELEM:
+               rx_conf.src_maxburst = 4;
+               break;
+       case SSP_RX_8_OR_MORE_ELEM:
+               rx_conf.src_maxburst = 8;
+               break;
+       case SSP_RX_16_OR_MORE_ELEM:
+               rx_conf.src_maxburst = 16;
+               break;
+       case SSP_RX_32_OR_MORE_ELEM:
+               rx_conf.src_maxburst = 32;
+               break;
+       default:
+               rx_conf.src_maxburst = pl022->vendor->fifodepth >> 1;
+               break;
+       }
+
+       switch (pl022->tx_lev_trig) {
+       case SSP_TX_1_OR_MORE_EMPTY_LOC:
+               tx_conf.dst_maxburst = 1;
+               break;
+       case SSP_TX_4_OR_MORE_EMPTY_LOC:
+               tx_conf.dst_maxburst = 4;
+               break;
+       case SSP_TX_8_OR_MORE_EMPTY_LOC:
+               tx_conf.dst_maxburst = 8;
+               break;
+       case SSP_TX_16_OR_MORE_EMPTY_LOC:
+               tx_conf.dst_maxburst = 16;
+               break;
+       case SSP_TX_32_OR_MORE_EMPTY_LOC:
+               tx_conf.dst_maxburst = 32;
+               break;
+       default:
+               tx_conf.dst_maxburst = pl022->vendor->fifodepth >> 1;
+               break;
+       }
+
+       switch (pl022->read) {
+       case READING_NULL:
+               /* Use the same as for writing */
+               rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
+               break;
+       case READING_U8:
+               rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+               break;
+       case READING_U16:
+               rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
+               break;
+       case READING_U32:
+               rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+               break;
+       }
+
+       switch (pl022->write) {
+       case WRITING_NULL:
+               /* Use the same as for reading */
+               tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
+               break;
+       case WRITING_U8:
+               tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+               break;
+       case WRITING_U16:
+               tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
+               break;
+       case WRITING_U32:
+               tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+               break;
+       }
+
+       /* SPI pecularity: we need to read and write the same width */
+       if (rx_conf.src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
+               rx_conf.src_addr_width = tx_conf.dst_addr_width;
+       if (tx_conf.dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
+               tx_conf.dst_addr_width = rx_conf.src_addr_width;
+       BUG_ON(rx_conf.src_addr_width != tx_conf.dst_addr_width);
+
+       dmaengine_slave_config(rxchan, &rx_conf);
+       dmaengine_slave_config(txchan, &tx_conf);
+
+       /* Create sglists for the transfers */
+       pages = DIV_ROUND_UP(pl022->cur_transfer->len, PAGE_SIZE);
+       dev_dbg(&pl022->adev->dev, "using %d pages for transfer\n", pages);
+
+       ret = sg_alloc_table(&pl022->sgt_rx, pages, GFP_ATOMIC);
+       if (ret)
+               goto err_alloc_rx_sg;
+
+       ret = sg_alloc_table(&pl022->sgt_tx, pages, GFP_ATOMIC);
+       if (ret)
+               goto err_alloc_tx_sg;
+
+       /* Fill in the scatterlists for the RX+TX buffers */
+       setup_dma_scatter(pl022, pl022->rx,
+                         pl022->cur_transfer->len, &pl022->sgt_rx);
+       setup_dma_scatter(pl022, pl022->tx,
+                         pl022->cur_transfer->len, &pl022->sgt_tx);
+
+       /* Map DMA buffers */
+       rx_sglen = dma_map_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
+                          pl022->sgt_rx.nents, DMA_FROM_DEVICE);
+       if (!rx_sglen)
+               goto err_rx_sgmap;
+
+       tx_sglen = dma_map_sg(txchan->device->dev, pl022->sgt_tx.sgl,
+                          pl022->sgt_tx.nents, DMA_TO_DEVICE);
+       if (!tx_sglen)
+               goto err_tx_sgmap;
+
+       /* Send both scatterlists */
+       rxdesc = dmaengine_prep_slave_sg(rxchan,
+                                     pl022->sgt_rx.sgl,
+                                     rx_sglen,
+                                     DMA_DEV_TO_MEM,
+                                     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+       if (!rxdesc)
+               goto err_rxdesc;
+
+       txdesc = dmaengine_prep_slave_sg(txchan,
+                                     pl022->sgt_tx.sgl,
+                                     tx_sglen,
+                                     DMA_MEM_TO_DEV,
+                                     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+       if (!txdesc)
+               goto err_txdesc;
+
+       /* Put the callback on the RX transfer only, that should finish last */
+       rxdesc->callback = dma_callback;
+       rxdesc->callback_param = pl022;
+
+       /* Submit and fire RX and TX with TX last so we're ready to read! */
+       dmaengine_submit(rxdesc);
+       dmaengine_submit(txdesc);
+       dma_async_issue_pending(rxchan);
+       dma_async_issue_pending(txchan);
+       pl022->dma_running = true;
+
+       return 0;
+
+err_txdesc:
+       dmaengine_terminate_all(txchan);
+err_rxdesc:
+       dmaengine_terminate_all(rxchan);
+       dma_unmap_sg(txchan->device->dev, pl022->sgt_tx.sgl,
+                    pl022->sgt_tx.nents, DMA_TO_DEVICE);
+err_tx_sgmap:
+       dma_unmap_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
+                    pl022->sgt_rx.nents, DMA_FROM_DEVICE);
+err_rx_sgmap:
+       sg_free_table(&pl022->sgt_tx);
+err_alloc_tx_sg:
+       sg_free_table(&pl022->sgt_rx);
+err_alloc_rx_sg:
+       return -ENOMEM;
+}
+
+static int pl022_dma_probe(struct pl022 *pl022)
+{
+       dma_cap_mask_t mask;
+
+       /* Try to acquire a generic DMA engine slave channel */
+       dma_cap_zero(mask);
+       dma_cap_set(DMA_SLAVE, mask);
+       /*
+        * We need both RX and TX channels to do DMA, else do none
+        * of them.
+        */
+       pl022->dma_rx_channel = dma_request_channel(mask,
+                                           pl022->master_info->dma_filter,
+                                           pl022->master_info->dma_rx_param);
+       if (!pl022->dma_rx_channel) {
+               dev_dbg(&pl022->adev->dev, "no RX DMA channel!\n");
+               goto err_no_rxchan;
+       }
+
+       pl022->dma_tx_channel = dma_request_channel(mask,
+                                           pl022->master_info->dma_filter,
+                                           pl022->master_info->dma_tx_param);
+       if (!pl022->dma_tx_channel) {
+               dev_dbg(&pl022->adev->dev, "no TX DMA channel!\n");
+               goto err_no_txchan;
+       }
+
+       pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
+       if (!pl022->dummypage)
+               goto err_no_dummypage;
+
+       dev_info(&pl022->adev->dev, "setup for DMA on RX %s, TX %s\n",
+                dma_chan_name(pl022->dma_rx_channel),
+                dma_chan_name(pl022->dma_tx_channel));
+
+       return 0;
+
+err_no_dummypage:
+       dma_release_channel(pl022->dma_tx_channel);
+err_no_txchan:
+       dma_release_channel(pl022->dma_rx_channel);
+       pl022->dma_rx_channel = NULL;
+err_no_rxchan:
+       dev_err(&pl022->adev->dev,
+                       "Failed to work in dma mode, work without dma!\n");
+       return -ENODEV;
+}
+
+static int pl022_dma_autoprobe(struct pl022 *pl022)
+{
+       struct device *dev = &pl022->adev->dev;
+       struct dma_chan *chan;
+       int err;
+
+       /* automatically configure DMA channels from platform, normally using DT */
+       chan = dma_request_chan(dev, "rx");
+       if (IS_ERR(chan)) {
+               err = PTR_ERR(chan);
+               goto err_no_rxchan;
+       }
+
+       pl022->dma_rx_channel = chan;
+
+       chan = dma_request_chan(dev, "tx");
+       if (IS_ERR(chan)) {
+               err = PTR_ERR(chan);
+               goto err_no_txchan;
+       }
+
+       pl022->dma_tx_channel = chan;
+
+       pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
+       if (!pl022->dummypage) {
+               err = -ENOMEM;
+               goto err_no_dummypage;
+       }
+
+       return 0;
+
+err_no_dummypage:
+       dma_release_channel(pl022->dma_tx_channel);
+       pl022->dma_tx_channel = NULL;
+err_no_txchan:
+       dma_release_channel(pl022->dma_rx_channel);
+       pl022->dma_rx_channel = NULL;
+err_no_rxchan:
+       return err;
+}
+
+static void terminate_dma(struct pl022 *pl022)
+{
+       struct dma_chan *rxchan = pl022->dma_rx_channel;
+       struct dma_chan *txchan = pl022->dma_tx_channel;
+
+       dmaengine_terminate_all(rxchan);
+       dmaengine_terminate_all(txchan);
+       unmap_free_dma_scatter(pl022);
+       pl022->dma_running = false;
+}
+
+static void pl022_dma_remove(struct pl022 *pl022)
+{
+       if (pl022->dma_running)
+               terminate_dma(pl022);
+       if (pl022->dma_tx_channel)
+               dma_release_channel(pl022->dma_tx_channel);
+       if (pl022->dma_rx_channel)
+               dma_release_channel(pl022->dma_rx_channel);
+       kfree(pl022->dummypage);
+}
+
+#else
+static inline int configure_dma(struct pl022 *pl022)
+{
+       return -ENODEV;
+}
+
+static inline int pl022_dma_autoprobe(struct pl022 *pl022)
+{
+       return 0;
+}
+
+static inline int pl022_dma_probe(struct pl022 *pl022)
+{
+       return 0;
+}
+
+static inline void pl022_dma_remove(struct pl022 *pl022)
+{
+}
+#endif
+
+/**
+ * pl022_interrupt_handler - Interrupt handler for SSP controller
+ * @irq: IRQ number
+ * @dev_id: Local device data
+ *
+ * This function handles interrupts generated for an interrupt based transfer.
+ * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the
+ * current message's state as STATE_ERROR and schedule the tasklet
+ * pump_transfers which will do the postprocessing of the current message by
+ * calling giveback(). Otherwise it reads data from RX FIFO till there is no
+ * more data, and writes data in TX FIFO till it is not full. If we complete
+ * the transfer we move to the next transfer and schedule the tasklet.
+ */
+static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id)
+{
+       struct pl022 *pl022 = dev_id;
+       struct spi_message *msg = pl022->cur_msg;
+       u16 irq_status = 0;
+
+       if (unlikely(!msg)) {
+               dev_err(&pl022->adev->dev,
+                       "bad message state in interrupt handler");
+               /* Never fail */
+               return IRQ_HANDLED;
+       }
+
+       /* Read the Interrupt Status Register */
+       irq_status = readw(SSP_MIS(pl022->virtbase));
+
+       if (unlikely(!irq_status))
+               return IRQ_NONE;
+
+       /*
+        * This handles the FIFO interrupts, the timeout
+        * interrupts are flatly ignored, they cannot be
+        * trusted.
+        */
+       if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) {
+               /*
+                * Overrun interrupt - bail out since our Data has been
+                * corrupted
+                */
+               dev_err(&pl022->adev->dev, "FIFO overrun\n");
+               if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF)
+                       dev_err(&pl022->adev->dev,
+                               "RXFIFO is full\n");
+
+               /*
+                * Disable and clear interrupts, disable SSP,
+                * mark message with bad status so it can be
+                * retried.
+                */
+               writew(DISABLE_ALL_INTERRUPTS,
+                      SSP_IMSC(pl022->virtbase));
+               writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
+               writew((readw(SSP_CR1(pl022->virtbase)) &
+                       (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
+               msg->state = STATE_ERROR;
+
+               /* Schedule message queue handler */
+               tasklet_schedule(&pl022->pump_transfers);
+               return IRQ_HANDLED;
+       }
+
+       readwriter(pl022);
+
+       if (pl022->tx == pl022->tx_end) {
+               /* Disable Transmit interrupt, enable receive interrupt */
+               writew((readw(SSP_IMSC(pl022->virtbase)) &
+                      ~SSP_IMSC_MASK_TXIM) | SSP_IMSC_MASK_RXIM,
+                      SSP_IMSC(pl022->virtbase));
+       }
+
+       /*
+        * Since all transactions must write as much as shall be read,
+        * we can conclude the entire transaction once RX is complete.
+        * At this point, all TX will always be finished.
+        */
+       if (pl022->rx >= pl022->rx_end) {
+               writew(DISABLE_ALL_INTERRUPTS,
+                      SSP_IMSC(pl022->virtbase));
+               writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
+               if (unlikely(pl022->rx > pl022->rx_end)) {
+                       dev_warn(&pl022->adev->dev, "read %u surplus "
+                                "bytes (did you request an odd "
+                                "number of bytes on a 16bit bus?)\n",
+                                (u32) (pl022->rx - pl022->rx_end));
+               }
+               /* Update total bytes transferred */
+               msg->actual_length += pl022->cur_transfer->len;
+               /* Move to next transfer */
+               msg->state = next_transfer(pl022);
+               if (msg->state != STATE_DONE && pl022->cur_transfer->cs_change)
+                       pl022_cs_control(pl022, SSP_CHIP_DESELECT);
+               tasklet_schedule(&pl022->pump_transfers);
+               return IRQ_HANDLED;
+       }
+
+       return IRQ_HANDLED;
+}
+
+/*
+ * This sets up the pointers to memory for the next message to
+ * send out on the SPI bus.
+ */
+static int set_up_next_transfer(struct pl022 *pl022,
+                               struct spi_transfer *transfer)
+{
+       int residue;
+
+       /* Sanity check the message for this bus width */
+       residue = pl022->cur_transfer->len % pl022->cur_chip->n_bytes;
+       if (unlikely(residue != 0)) {
+               dev_err(&pl022->adev->dev,
+                       "message of %u bytes to transmit but the current "
+                       "chip bus has a data width of %u bytes!\n",
+                       pl022->cur_transfer->len,
+                       pl022->cur_chip->n_bytes);
+               dev_err(&pl022->adev->dev, "skipping this message\n");
+               return -EIO;
+       }
+       pl022->tx = (void *)transfer->tx_buf;
+       pl022->tx_end = pl022->tx + pl022->cur_transfer->len;
+       pl022->rx = (void *)transfer->rx_buf;
+       pl022->rx_end = pl022->rx + pl022->cur_transfer->len;
+       pl022->write =
+           pl022->tx ? pl022->cur_chip->write : WRITING_NULL;
+       pl022->read = pl022->rx ? pl022->cur_chip->read : READING_NULL;
+       return 0;
+}
+
+/**
+ * pump_transfers - Tasklet function which schedules next transfer
+ * when running in interrupt or DMA transfer mode.
+ * @data: SSP driver private data structure
+ *
+ */
+static void pump_transfers(unsigned long data)
+{
+       struct pl022 *pl022 = (struct pl022 *) data;
+       struct spi_message *message = NULL;
+       struct spi_transfer *transfer = NULL;
+       struct spi_transfer *previous = NULL;
+
+       /* Get current state information */
+       message = pl022->cur_msg;
+       transfer = pl022->cur_transfer;
+
+       /* Handle for abort */
+       if (message->state == STATE_ERROR) {
+               message->status = -EIO;
+               giveback(pl022);
+               return;
+       }
+
+       /* Handle end of message */
+       if (message->state == STATE_DONE) {
+               message->status = 0;
+               giveback(pl022);
+               return;
+       }
+
+       /* Delay if requested at end of transfer before CS change */
+       if (message->state == STATE_RUNNING) {
+               previous = list_entry(transfer->transfer_list.prev,
+                                       struct spi_transfer,
+                                       transfer_list);
+               /*
+                * FIXME: This runs in interrupt context.
+                * Is this really smart?
+                */
+               spi_transfer_delay_exec(previous);
+
+               /* Reselect chip select only if cs_change was requested */
+               if (previous->cs_change)
+                       pl022_cs_control(pl022, SSP_CHIP_SELECT);
+       } else {
+               /* STATE_START */
+               message->state = STATE_RUNNING;
+       }
+
+       if (set_up_next_transfer(pl022, transfer)) {
+               message->state = STATE_ERROR;
+               message->status = -EIO;
+               giveback(pl022);
+               return;
+       }
+       /* Flush the FIFOs and let's go! */
+       flush(pl022);
+
+       if (pl022->cur_chip->enable_dma) {
+               if (configure_dma(pl022)) {
+                       dev_dbg(&pl022->adev->dev,
+                               "configuration of DMA failed, fall back to interrupt mode\n");
+                       goto err_config_dma;
+               }
+               return;
+       }
+
+err_config_dma:
+       /* enable all interrupts except RX */
+       writew(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM, SSP_IMSC(pl022->virtbase));
+}
+
+static void do_interrupt_dma_transfer(struct pl022 *pl022)
+{
+       /*
+        * Default is to enable all interrupts except RX -
+        * this will be enabled once TX is complete
+        */
+       u32 irqflags = (u32)(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM);
+
+       /* Enable target chip, if not already active */
+       if (!pl022->next_msg_cs_active)
+               pl022_cs_control(pl022, SSP_CHIP_SELECT);
+
+       if (set_up_next_transfer(pl022, pl022->cur_transfer)) {
+               /* Error path */
+               pl022->cur_msg->state = STATE_ERROR;
+               pl022->cur_msg->status = -EIO;
+               giveback(pl022);
+               return;
+       }
+       /* If we're using DMA, set up DMA here */
+       if (pl022->cur_chip->enable_dma) {
+               /* Configure DMA transfer */
+               if (configure_dma(pl022)) {
+                       dev_dbg(&pl022->adev->dev,
+                               "configuration of DMA failed, fall back to interrupt mode\n");
+                       goto err_config_dma;
+               }
+               /* Disable interrupts in DMA mode, IRQ from DMA controller */
+               irqflags = DISABLE_ALL_INTERRUPTS;
+       }
+err_config_dma:
+       /* Enable SSP, turn on interrupts */
+       writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
+              SSP_CR1(pl022->virtbase));
+       writew(irqflags, SSP_IMSC(pl022->virtbase));
+}
+
+static void print_current_status(struct pl022 *pl022)
+{
+       u32 read_cr0;
+       u16 read_cr1, read_dmacr, read_sr;
+
+       if (pl022->vendor->extended_cr)
+               read_cr0 = readl(SSP_CR0(pl022->virtbase));
+       else
+               read_cr0 = readw(SSP_CR0(pl022->virtbase));
+       read_cr1 = readw(SSP_CR1(pl022->virtbase));
+       read_dmacr = readw(SSP_DMACR(pl022->virtbase));
+       read_sr = readw(SSP_SR(pl022->virtbase));
+
+       dev_warn(&pl022->adev->dev, "spi-pl022 CR0: %x\n", read_cr0);
+       dev_warn(&pl022->adev->dev, "spi-pl022 CR1: %x\n", read_cr1);
+       dev_warn(&pl022->adev->dev, "spi-pl022 DMACR: %x\n", read_dmacr);
+       dev_warn(&pl022->adev->dev, "spi-pl022 SR: %x\n", read_sr);
+       dev_warn(&pl022->adev->dev,
+                       "spi-pl022 exp_fifo_level/fifodepth: %u/%d\n",
+                       pl022->exp_fifo_level,
+                       pl022->vendor->fifodepth);
+
+}
+
+static void do_polling_transfer(struct pl022 *pl022)
+{
+       struct spi_message *message = NULL;
+       struct spi_transfer *transfer = NULL;
+       struct spi_transfer *previous = NULL;
+       unsigned long time, timeout;
+
+       message = pl022->cur_msg;
+
+       while (message->state != STATE_DONE) {
+               /* Handle for abort */
+               if (message->state == STATE_ERROR)
+                       break;
+               transfer = pl022->cur_transfer;
+
+               /* Delay if requested at end of transfer */
+               if (message->state == STATE_RUNNING) {
+                       previous =
+                           list_entry(transfer->transfer_list.prev,
+                                      struct spi_transfer, transfer_list);
+                       spi_transfer_delay_exec(previous);
+                       if (previous->cs_change)
+                               pl022_cs_control(pl022, SSP_CHIP_SELECT);
+               } else {
+                       /* STATE_START */
+                       message->state = STATE_RUNNING;
+                       if (!pl022->next_msg_cs_active)
+                               pl022_cs_control(pl022, SSP_CHIP_SELECT);
+               }
+
+               /* Configuration Changing Per Transfer */
+               if (set_up_next_transfer(pl022, transfer)) {
+                       /* Error path */
+                       message->state = STATE_ERROR;
+                       break;
+               }
+               /* Flush FIFOs and enable SSP */
+               flush(pl022);
+               writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
+                      SSP_CR1(pl022->virtbase));
+
+               dev_dbg(&pl022->adev->dev, "polling transfer ongoing ...\n");
+
+               timeout = jiffies + msecs_to_jiffies(SPI_POLLING_TIMEOUT);
+               while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end) {
+                       time = jiffies;
+                       readwriter(pl022);
+                       if (time_after(time, timeout)) {
+                               dev_warn(&pl022->adev->dev,
+                               "%s: timeout!\n", __func__);
+                               message->state = STATE_TIMEOUT;
+                               print_current_status(pl022);
+                               goto out;
+                       }
+                       cpu_relax();
+               }
+
+               /* Update total byte transferred */
+               message->actual_length += pl022->cur_transfer->len;
+               /* Move to next transfer */
+               message->state = next_transfer(pl022);
+               if (message->state != STATE_DONE
+                   && pl022->cur_transfer->cs_change)
+                       pl022_cs_control(pl022, SSP_CHIP_DESELECT);
+       }
+out:
+       /* Handle end of message */
+       if (message->state == STATE_DONE)
+               message->status = 0;
+       else if (message->state == STATE_TIMEOUT)
+               message->status = -EAGAIN;
+       else
+               message->status = -EIO;
+
+       giveback(pl022);
+       return;
+}
+
+static int pl022_transfer_one_message(struct spi_master *master,
+                                     struct spi_message *msg)
+{
+       struct pl022 *pl022 = spi_master_get_devdata(master);
+
+       /* Initial message state */
+       pl022->cur_msg = msg;
+       msg->state = STATE_START;
+
+       pl022->cur_transfer = list_entry(msg->transfers.next,
+                                        struct spi_transfer, transfer_list);
+
+       /* Setup the SPI using the per chip configuration */
+       pl022->cur_chip = spi_get_ctldata(msg->spi);
+       pl022->cur_cs = msg->spi->chip_select;
+       /* This is always available but may be set to -ENOENT */
+       pl022->cur_gpiod = msg->spi->cs_gpiod;
+
+       restore_state(pl022);
+       flush(pl022);
+
+       if (pl022->cur_chip->xfer_type == POLLING_TRANSFER)
+               do_polling_transfer(pl022);
+       else
+               do_interrupt_dma_transfer(pl022);
+
+       return 0;
+}
+
+static int pl022_unprepare_transfer_hardware(struct spi_master *master)
+{
+       struct pl022 *pl022 = spi_master_get_devdata(master);
+
+       /* nothing more to do - disable spi/ssp and power off */
+       writew((readw(SSP_CR1(pl022->virtbase)) &
+               (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
+
+       return 0;
+}
+
+static int verify_controller_parameters(struct pl022 *pl022,
+                               struct pl022_config_chip const *chip_info)
+{
+       if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI)
+           || (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) {
+               dev_err(&pl022->adev->dev,
+                       "interface is configured incorrectly\n");
+               return -EINVAL;
+       }
+       if ((chip_info->iface == SSP_INTERFACE_UNIDIRECTIONAL) &&
+           (!pl022->vendor->unidir)) {
+               dev_err(&pl022->adev->dev,
+                       "unidirectional mode not supported in this "
+                       "hardware version\n");
+               return -EINVAL;
+       }
+       if ((chip_info->hierarchy != SSP_MASTER)
+           && (chip_info->hierarchy != SSP_SLAVE)) {
+               dev_err(&pl022->adev->dev,
+                       "hierarchy is configured incorrectly\n");
+               return -EINVAL;
+       }
+       if ((chip_info->com_mode != INTERRUPT_TRANSFER)
+           && (chip_info->com_mode != DMA_TRANSFER)
+           && (chip_info->com_mode != POLLING_TRANSFER)) {
+               dev_err(&pl022->adev->dev,
+                       "Communication mode is configured incorrectly\n");
+               return -EINVAL;
+       }
+       switch (chip_info->rx_lev_trig) {
+       case SSP_RX_1_OR_MORE_ELEM:
+       case SSP_RX_4_OR_MORE_ELEM:
+       case SSP_RX_8_OR_MORE_ELEM:
+               /* These are always OK, all variants can handle this */
+               break;
+       case SSP_RX_16_OR_MORE_ELEM:
+               if (pl022->vendor->fifodepth < 16) {
+                       dev_err(&pl022->adev->dev,
+                       "RX FIFO Trigger Level is configured incorrectly\n");
+                       return -EINVAL;
+               }
+               break;
+       case SSP_RX_32_OR_MORE_ELEM:
+               if (pl022->vendor->fifodepth < 32) {
+                       dev_err(&pl022->adev->dev,
+                       "RX FIFO Trigger Level is configured incorrectly\n");
+                       return -EINVAL;
+               }
+               break;
+       default:
+               dev_err(&pl022->adev->dev,
+                       "RX FIFO Trigger Level is configured incorrectly\n");
+               return -EINVAL;
+       }
+       switch (chip_info->tx_lev_trig) {
+       case SSP_TX_1_OR_MORE_EMPTY_LOC:
+       case SSP_TX_4_OR_MORE_EMPTY_LOC:
+       case SSP_TX_8_OR_MORE_EMPTY_LOC:
+               /* These are always OK, all variants can handle this */
+               break;
+       case SSP_TX_16_OR_MORE_EMPTY_LOC:
+               if (pl022->vendor->fifodepth < 16) {
+                       dev_err(&pl022->adev->dev,
+                       "TX FIFO Trigger Level is configured incorrectly\n");
+                       return -EINVAL;
+               }
+               break;
+       case SSP_TX_32_OR_MORE_EMPTY_LOC:
+               if (pl022->vendor->fifodepth < 32) {
+                       dev_err(&pl022->adev->dev,
+                       "TX FIFO Trigger Level is configured incorrectly\n");
+                       return -EINVAL;
+               }
+               break;
+       default:
+               dev_err(&pl022->adev->dev,
+                       "TX FIFO Trigger Level is configured incorrectly\n");
+               return -EINVAL;
+       }
+       if (chip_info->iface == SSP_INTERFACE_NATIONAL_MICROWIRE) {
+               if ((chip_info->ctrl_len < SSP_BITS_4)
+                   || (chip_info->ctrl_len > SSP_BITS_32)) {
+                       dev_err(&pl022->adev->dev,
+                               "CTRL LEN is configured incorrectly\n");
+                       return -EINVAL;
+               }
+               if ((chip_info->wait_state != SSP_MWIRE_WAIT_ZERO)
+                   && (chip_info->wait_state != SSP_MWIRE_WAIT_ONE)) {
+                       dev_err(&pl022->adev->dev,
+                               "Wait State is configured incorrectly\n");
+                       return -EINVAL;
+               }
+               /* Half duplex is only available in the ST Micro version */
+               if (pl022->vendor->extended_cr) {
+                       if ((chip_info->duplex !=
+                            SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
+                           && (chip_info->duplex !=
+                               SSP_MICROWIRE_CHANNEL_HALF_DUPLEX)) {
+                               dev_err(&pl022->adev->dev,
+                                       "Microwire duplex mode is configured incorrectly\n");
+                               return -EINVAL;
+                       }
+               } else {
+                       if (chip_info->duplex != SSP_MICROWIRE_CHANNEL_FULL_DUPLEX) {
+                               dev_err(&pl022->adev->dev,
+                                       "Microwire half duplex mode requested,"
+                                       " but this is only available in the"
+                                       " ST version of PL022\n");
+                               return -EINVAL;
+                       }
+               }
+       }
+       return 0;
+}
+
+static inline u32 spi_rate(u32 rate, u16 cpsdvsr, u16 scr)
+{
+       return rate / (cpsdvsr * (1 + scr));
+}
+
+static int calculate_effective_freq(struct pl022 *pl022, int freq, struct
+                                   ssp_clock_params * clk_freq)
+{
+       /* Lets calculate the frequency parameters */
+       u16 cpsdvsr = CPSDVR_MIN, scr = SCR_MIN;
+       u32 rate, max_tclk, min_tclk, best_freq = 0, best_cpsdvsr = 0,
+               best_scr = 0, tmp, found = 0;
+
+       rate = clk_get_rate(pl022->clk);
+       /* cpsdvscr = 2 & scr 0 */
+       max_tclk = spi_rate(rate, CPSDVR_MIN, SCR_MIN);
+       /* cpsdvsr = 254 & scr = 255 */
+       min_tclk = spi_rate(rate, CPSDVR_MAX, SCR_MAX);
+
+       if (freq > max_tclk)
+               dev_warn(&pl022->adev->dev,
+                       "Max speed that can be programmed is %d Hz, you requested %d\n",
+                       max_tclk, freq);
+
+       if (freq < min_tclk) {
+               dev_err(&pl022->adev->dev,
+                       "Requested frequency: %d Hz is less than minimum possible %d Hz\n",
+                       freq, min_tclk);
+               return -EINVAL;
+       }
+
+       /*
+        * best_freq will give closest possible available rate (<= requested
+        * freq) for all values of scr & cpsdvsr.
+        */
+       while ((cpsdvsr <= CPSDVR_MAX) && !found) {
+               while (scr <= SCR_MAX) {
+                       tmp = spi_rate(rate, cpsdvsr, scr);
+
+                       if (tmp > freq) {
+                               /* we need lower freq */
+                               scr++;
+                               continue;
+                       }
+
+                       /*
+                        * If found exact value, mark found and break.
+                        * If found more closer value, update and break.
+                        */
+                       if (tmp > best_freq) {
+                               best_freq = tmp;
+                               best_cpsdvsr = cpsdvsr;
+                               best_scr = scr;
+
+                               if (tmp == freq)
+                                       found = 1;
+                       }
+                       /*
+                        * increased scr will give lower rates, which are not
+                        * required
+                        */
+                       break;
+               }
+               cpsdvsr += 2;
+               scr = SCR_MIN;
+       }
+
+       WARN(!best_freq, "pl022: Matching cpsdvsr and scr not found for %d Hz rate \n",
+                       freq);
+
+       clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF);
+       clk_freq->scr = (u8) (best_scr & 0xFF);
+       dev_dbg(&pl022->adev->dev,
+               "SSP Target Frequency is: %u, Effective Frequency is %u\n",
+               freq, best_freq);
+       dev_dbg(&pl022->adev->dev, "SSP cpsdvsr = %d, scr = %d\n",
+               clk_freq->cpsdvsr, clk_freq->scr);
+
+       return 0;
+}
+
+/*
+ * A piece of default chip info unless the platform
+ * supplies it.
+ */
+static const struct pl022_config_chip pl022_default_chip_info = {
+       .com_mode = INTERRUPT_TRANSFER,
+       .iface = SSP_INTERFACE_MOTOROLA_SPI,
+       .hierarchy = SSP_MASTER,
+       .slave_tx_disable = DO_NOT_DRIVE_TX,
+       .rx_lev_trig = SSP_RX_1_OR_MORE_ELEM,
+       .tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC,
+       .ctrl_len = SSP_BITS_8,
+       .wait_state = SSP_MWIRE_WAIT_ZERO,
+       .duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX,
+};
+
+/**
+ * pl022_setup - setup function registered to SPI master framework
+ * @spi: spi device which is requesting setup
+ *
+ * This function is registered to the SPI framework for this SPI master
+ * controller. If it is the first time when setup is called by this device,
+ * this function will initialize the runtime state for this chip and save
+ * the same in the device structure. Else it will update the runtime info
+ * with the updated chip info. Nothing is really being written to the
+ * controller hardware here, that is not done until the actual transfer
+ * commence.
+ */
+static int pl022_setup(struct spi_device *spi)
+{
+       struct pl022_config_chip const *chip_info;
+       struct pl022_config_chip chip_info_dt;
+       struct chip_data *chip;
+       struct ssp_clock_params clk_freq = { .cpsdvsr = 0, .scr = 0};
+       int status = 0;
+       struct pl022 *pl022 = spi_master_get_devdata(spi->master);
+       unsigned int bits = spi->bits_per_word;
+       u32 tmp;
+       struct device_node *np = spi->dev.of_node;
+
+       if (!spi->max_speed_hz)
+               return -EINVAL;
+
+       /* Get controller_state if one is supplied */
+       chip = spi_get_ctldata(spi);
+
+       if (chip == NULL) {
+               chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
+               if (!chip)
+                       return -ENOMEM;
+               dev_dbg(&spi->dev,
+                       "allocated memory for controller's runtime state\n");
+       }
+
+       /* Get controller data if one is supplied */
+       chip_info = spi->controller_data;
+
+       if (chip_info == NULL) {
+               if (np) {
+                       chip_info_dt = pl022_default_chip_info;
+
+                       chip_info_dt.hierarchy = SSP_MASTER;
+                       of_property_read_u32(np, "pl022,interface",
+                               &chip_info_dt.iface);
+                       of_property_read_u32(np, "pl022,com-mode",
+                               &chip_info_dt.com_mode);
+                       of_property_read_u32(np, "pl022,rx-level-trig",
+                               &chip_info_dt.rx_lev_trig);
+                       of_property_read_u32(np, "pl022,tx-level-trig",
+                               &chip_info_dt.tx_lev_trig);
+                       of_property_read_u32(np, "pl022,ctrl-len",
+                               &chip_info_dt.ctrl_len);
+                       of_property_read_u32(np, "pl022,wait-state",
+                               &chip_info_dt.wait_state);
+                       of_property_read_u32(np, "pl022,duplex",
+                               &chip_info_dt.duplex);
+
+                       chip_info = &chip_info_dt;
+               } else {
+                       chip_info = &pl022_default_chip_info;
+                       /* spi_board_info.controller_data not is supplied */
+                       dev_dbg(&spi->dev,
+                               "using default controller_data settings\n");
+               }
+       } else
+               dev_dbg(&spi->dev,
+                       "using user supplied controller_data settings\n");
+
+       /*
+        * We can override with custom divisors, else we use the board
+        * frequency setting
+        */
+       if ((0 == chip_info->clk_freq.cpsdvsr)
+           && (0 == chip_info->clk_freq.scr)) {
+               status = calculate_effective_freq(pl022,
+                                                 spi->max_speed_hz,
+                                                 &clk_freq);
+               if (status < 0)
+                       goto err_config_params;
+       } else {
+               memcpy(&clk_freq, &chip_info->clk_freq, sizeof(clk_freq));
+               if ((clk_freq.cpsdvsr % 2) != 0)
+                       clk_freq.cpsdvsr =
+                               clk_freq.cpsdvsr - 1;
+       }
+       if ((clk_freq.cpsdvsr < CPSDVR_MIN)
+           || (clk_freq.cpsdvsr > CPSDVR_MAX)) {
+               status = -EINVAL;
+               dev_err(&spi->dev,
+                       "cpsdvsr is configured incorrectly\n");
+               goto err_config_params;
+       }
+
+       status = verify_controller_parameters(pl022, chip_info);
+       if (status) {
+               dev_err(&spi->dev, "controller data is incorrect");
+               goto err_config_params;
+       }
+
+       pl022->rx_lev_trig = chip_info->rx_lev_trig;
+       pl022->tx_lev_trig = chip_info->tx_lev_trig;
+
+       /* Now set controller state based on controller data */
+       chip->xfer_type = chip_info->com_mode;
+
+       /* Check bits per word with vendor specific range */
+       if ((bits <= 3) || (bits > pl022->vendor->max_bpw)) {
+               status = -ENOTSUPP;
+               dev_err(&spi->dev, "illegal data size for this controller!\n");
+               dev_err(&spi->dev, "This controller can only handle 4 <= n <= %d bit words\n",
+                               pl022->vendor->max_bpw);
+               goto err_config_params;
+       } else if (bits <= 8) {
+               dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n");
+               chip->n_bytes = 1;
+               chip->read = READING_U8;
+               chip->write = WRITING_U8;
+       } else if (bits <= 16) {
+               dev_dbg(&spi->dev, "9 <= n <= 16 bits per word\n");
+               chip->n_bytes = 2;
+               chip->read = READING_U16;
+               chip->write = WRITING_U16;
+       } else {
+               dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n");
+               chip->n_bytes = 4;
+               chip->read = READING_U32;
+               chip->write = WRITING_U32;
+       }
+
+       /* Now Initialize all register settings required for this chip */
+       chip->cr0 = 0;
+       chip->cr1 = 0;
+       chip->dmacr = 0;
+       chip->cpsr = 0;
+       if ((chip_info->com_mode == DMA_TRANSFER)
+           && ((pl022->master_info)->enable_dma)) {
+               chip->enable_dma = true;
+               dev_dbg(&spi->dev, "DMA mode set in controller state\n");
+               SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
+                              SSP_DMACR_MASK_RXDMAE, 0);
+               SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
+                              SSP_DMACR_MASK_TXDMAE, 1);
+       } else {
+               chip->enable_dma = false;
+               dev_dbg(&spi->dev, "DMA mode NOT set in controller state\n");
+               SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
+                              SSP_DMACR_MASK_RXDMAE, 0);
+               SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
+                              SSP_DMACR_MASK_TXDMAE, 1);
+       }
+
+       chip->cpsr = clk_freq.cpsdvsr;
+
+       /* Special setup for the ST micro extended control registers */
+       if (pl022->vendor->extended_cr) {
+               u32 etx;
+
+               if (pl022->vendor->pl023) {
+                       /* These bits are only in the PL023 */
+                       SSP_WRITE_BITS(chip->cr1, chip_info->clkdelay,
+                                      SSP_CR1_MASK_FBCLKDEL_ST, 13);
+               } else {
+                       /* These bits are in the PL022 but not PL023 */
+                       SSP_WRITE_BITS(chip->cr0, chip_info->duplex,
+                                      SSP_CR0_MASK_HALFDUP_ST, 5);
+                       SSP_WRITE_BITS(chip->cr0, chip_info->ctrl_len,
+                                      SSP_CR0_MASK_CSS_ST, 16);
+                       SSP_WRITE_BITS(chip->cr0, chip_info->iface,
+                                      SSP_CR0_MASK_FRF_ST, 21);
+                       SSP_WRITE_BITS(chip->cr1, chip_info->wait_state,
+                                      SSP_CR1_MASK_MWAIT_ST, 6);
+               }
+               SSP_WRITE_BITS(chip->cr0, bits - 1,
+                              SSP_CR0_MASK_DSS_ST, 0);
+
+               if (spi->mode & SPI_LSB_FIRST) {
+                       tmp = SSP_RX_LSB;
+                       etx = SSP_TX_LSB;
+               } else {
+                       tmp = SSP_RX_MSB;
+                       etx = SSP_TX_MSB;
+               }
+               SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_RENDN_ST, 4);
+               SSP_WRITE_BITS(chip->cr1, etx, SSP_CR1_MASK_TENDN_ST, 5);
+               SSP_WRITE_BITS(chip->cr1, chip_info->rx_lev_trig,
+                              SSP_CR1_MASK_RXIFLSEL_ST, 7);
+               SSP_WRITE_BITS(chip->cr1, chip_info->tx_lev_trig,
+                              SSP_CR1_MASK_TXIFLSEL_ST, 10);
+       } else {
+               SSP_WRITE_BITS(chip->cr0, bits - 1,
+                              SSP_CR0_MASK_DSS, 0);
+               SSP_WRITE_BITS(chip->cr0, chip_info->iface,
+                              SSP_CR0_MASK_FRF, 4);
+       }
+
+       /* Stuff that is common for all versions */
+       if (spi->mode & SPI_CPOL)
+               tmp = SSP_CLK_POL_IDLE_HIGH;
+       else
+               tmp = SSP_CLK_POL_IDLE_LOW;
+       SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPO, 6);
+
+       if (spi->mode & SPI_CPHA)
+               tmp = SSP_CLK_SECOND_EDGE;
+       else
+               tmp = SSP_CLK_FIRST_EDGE;
+       SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPH, 7);
+
+       SSP_WRITE_BITS(chip->cr0, clk_freq.scr, SSP_CR0_MASK_SCR, 8);
+       /* Loopback is available on all versions except PL023 */
+       if (pl022->vendor->loopback) {
+               if (spi->mode & SPI_LOOP)
+                       tmp = LOOPBACK_ENABLED;
+               else
+                       tmp = LOOPBACK_DISABLED;
+               SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_LBM, 0);
+       }
+       SSP_WRITE_BITS(chip->cr1, SSP_DISABLED, SSP_CR1_MASK_SSE, 1);
+       SSP_WRITE_BITS(chip->cr1, chip_info->hierarchy, SSP_CR1_MASK_MS, 2);
+       SSP_WRITE_BITS(chip->cr1, chip_info->slave_tx_disable, SSP_CR1_MASK_SOD,
+               3);
+
+       /* Save controller_state */
+       spi_set_ctldata(spi, chip);
+       return status;
+ err_config_params:
+       spi_set_ctldata(spi, NULL);
+       kfree(chip);
+       return status;
+}
+
+/**
+ * pl022_cleanup - cleanup function registered to SPI master framework
+ * @spi: spi device which is requesting cleanup
+ *
+ * This function is registered to the SPI framework for this SPI master
+ * controller. It will free the runtime state of chip.
+ */
+static void pl022_cleanup(struct spi_device *spi)
+{
+       struct chip_data *chip = spi_get_ctldata(spi);
+
+       spi_set_ctldata(spi, NULL);
+       kfree(chip);
+}
+
+static struct pl022_ssp_controller *
+pl022_platform_data_dt_get(struct device *dev)
+{
+       struct device_node *np = dev->of_node;
+       struct pl022_ssp_controller *pd;
+
+       if (!np) {
+               dev_err(dev, "no dt node defined\n");
+               return NULL;
+       }
+
+       pd = devm_kzalloc(dev, sizeof(struct pl022_ssp_controller), GFP_KERNEL);
+       if (!pd)
+               return NULL;
+
+       pd->bus_id = -1;
+       pd->enable_dma = 1;
+       of_property_read_u32(np, "pl022,autosuspend-delay",
+                            &pd->autosuspend_delay);
+       pd->rt = of_property_read_bool(np, "pl022,rt");
+
+       return pd;
+}
+
+static int pl022_probe(struct amba_device *adev, const struct amba_id *id)
+{
+       struct device *dev = &adev->dev;
+       struct pl022_ssp_controller *platform_info =
+                       dev_get_platdata(&adev->dev);
+       struct spi_master *master;
+       struct pl022 *pl022 = NULL;     /*Data for this driver */
+       int status = 0;
+
+       dev_info(&adev->dev,
+               "ARM PL022 driver for StarFive SoC platform, device ID: 0x%08x\n",
+               adev->periphid);
+       if (!platform_info && IS_ENABLED(CONFIG_OF))
+               platform_info = pl022_platform_data_dt_get(dev);
+
+       if (!platform_info) {
+               dev_err(dev, "probe: no platform data defined\n");
+               return -ENODEV;
+       }
+
+       /* Allocate master with space for data */
+       master = spi_alloc_master(dev, sizeof(struct pl022));
+       if (master == NULL) {
+               dev_err(&adev->dev, "probe - cannot alloc SPI master\n");
+               return -ENOMEM;
+       }
+
+       pl022 = spi_master_get_devdata(master);
+       pl022->master = master;
+       pl022->master_info = platform_info;
+       pl022->adev = adev;
+       pl022->vendor = id->data;
+
+       /*
+        * Bus Number Which has been Assigned to this SSP controller
+        * on this board
+        */
+       master->bus_num = platform_info->bus_id;
+       master->cleanup = pl022_cleanup;
+       master->setup = pl022_setup;
+       master->auto_runtime_pm = true;
+       master->transfer_one_message = pl022_transfer_one_message;
+       master->unprepare_transfer_hardware = pl022_unprepare_transfer_hardware;
+       master->rt = platform_info->rt;
+       master->dev.of_node = dev->of_node;
+       master->use_gpio_descriptors = true;
+
+       /*
+        * Supports mode 0-3, loopback, and active low CS. Transfers are
+        * always MS bit first on the original pl022.
+        */
+       master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
+       if (pl022->vendor->extended_cr)
+               master->mode_bits |= SPI_LSB_FIRST;
+
+       dev_dbg(&adev->dev, "BUSNO: %d\n", master->bus_num);
+
+       status = amba_request_regions(adev, NULL);
+       if (status)
+               goto err_no_ioregion;
+
+       pl022->phybase = adev->res.start;
+       pl022->virtbase = devm_ioremap(dev, adev->res.start,
+                                      resource_size(&adev->res));
+       if (pl022->virtbase == NULL) {
+               status = -ENOMEM;
+               goto err_no_ioremap;
+       }
+       dev_info(&adev->dev, "mapped registers from %pa to %p\n",
+               &adev->res.start, pl022->virtbase);
+
+       pl022->clk = devm_clk_get(&adev->dev, NULL);
+       if (IS_ERR(pl022->clk)) {
+               status = PTR_ERR(pl022->clk);
+               dev_err(&adev->dev, "could not retrieve SSP/SPI bus clock\n");
+               goto err_no_clk;
+       }
+
+       status = clk_prepare_enable(pl022->clk);
+       if (status) {
+               dev_err(&adev->dev, "could not enable SSP/SPI bus clock\n");
+               goto err_no_clk_en;
+       }
+
+       pl022->rst = devm_reset_control_get_exclusive(&adev->dev, "rst_apb");
+       if (!IS_ERR(pl022->rst)) {
+               status = reset_control_deassert(pl022->rst);
+               if (status) {
+                       dev_err(&adev->dev, "could not deassert SSP/SPI bus reset\n");
+                       goto err_no_rst_clr;
+               }
+       } else {
+               status = PTR_ERR(pl022->rst);
+               dev_err(&adev->dev, "could not retrieve SSP/SPI bus reset\n");
+               goto err_no_rst;
+       }
+
+       /* Initialize transfer pump */
+       tasklet_init(&pl022->pump_transfers, pump_transfers,
+                    (unsigned long)pl022);
+
+       /* Disable SSP */
+       writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)),
+              SSP_CR1(pl022->virtbase));
+       load_ssp_default_config(pl022);
+
+       status = devm_request_irq(dev, adev->irq[0], pl022_interrupt_handler,
+                                 0, "pl022", pl022);
+       if (status < 0) {
+               dev_err(&adev->dev, "probe - cannot get IRQ (%d)\n", status);
+               goto err_no_irq;
+       }
+
+       /* Get DMA channels, try autoconfiguration first */
+       status = pl022_dma_autoprobe(pl022);
+       if (status == -EPROBE_DEFER) {
+               dev_dbg(dev, "deferring probe to get DMA channel\n");
+               goto err_no_irq;
+       }
+
+       /* If that failed, use channels from platform_info */
+       if (status == 0)
+               platform_info->enable_dma = 1;
+       else if (platform_info->enable_dma) {
+               status = pl022_dma_probe(pl022);
+               if (status != 0)
+                       platform_info->enable_dma = 0;
+       }
+
+       /* Register with the SPI framework */
+       amba_set_drvdata(adev, pl022);
+       status = devm_spi_register_master(&adev->dev, master);
+       if (status != 0) {
+               dev_err(&adev->dev,
+                       "probe - problem registering spi master\n");
+               goto err_spi_register;
+       }
+       dev_dbg(dev, "probe succeeded\n");
+
+       /* let runtime pm put suspend */
+       if (platform_info->autosuspend_delay > 0) {
+               dev_info(&adev->dev,
+                       "will use autosuspend for runtime pm, delay %dms\n",
+                       platform_info->autosuspend_delay);
+               pm_runtime_set_autosuspend_delay(dev,
+                       platform_info->autosuspend_delay);
+               pm_runtime_use_autosuspend(dev);
+       }
+       pm_runtime_put(dev);
+
+       return 0;
+
+ err_spi_register:
+       if (platform_info->enable_dma)
+               pl022_dma_remove(pl022);
+ err_no_irq:
+       reset_control_assert(pl022->rst);
+ err_no_rst_clr:
+ err_no_rst:
+       clk_disable_unprepare(pl022->clk);
+ err_no_clk_en:
+ err_no_clk:
+ err_no_ioremap:
+       amba_release_regions(adev);
+ err_no_ioregion:
+       spi_master_put(master);
+       return status;
+}
+
+static void
+pl022_remove(struct amba_device *adev)
+{
+       struct pl022 *pl022 = amba_get_drvdata(adev);
+
+       if (!pl022)
+               return;
+
+       /*
+        * undo pm_runtime_put() in probe.  I assume that we're not
+        * accessing the primecell here.
+        */
+       pm_runtime_get_noresume(&adev->dev);
+
+       load_ssp_default_config(pl022);
+       if (pl022->master_info->enable_dma)
+               pl022_dma_remove(pl022);
+
+       clk_disable_unprepare(pl022->clk);
+       amba_release_regions(adev);
+       tasklet_disable(&pl022->pump_transfers);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int pl022_suspend(struct device *dev)
+{
+       struct pl022 *pl022 = dev_get_drvdata(dev);
+       int ret;
+
+       ret = spi_master_suspend(pl022->master);
+       if (ret)
+               return ret;
+
+       ret = pm_runtime_force_suspend(dev);
+       if (ret) {
+               spi_master_resume(pl022->master);
+               return ret;
+       }
+
+       pinctrl_pm_select_sleep_state(dev);
+
+       dev_dbg(dev, "suspended\n");
+       return 0;
+}
+
+static int pl022_resume(struct device *dev)
+{
+       struct pl022 *pl022 = dev_get_drvdata(dev);
+       int ret;
+
+       ret = pm_runtime_force_resume(dev);
+       if (ret)
+               dev_err(dev, "problem resuming\n");
+
+       /* Start the queue running */
+       ret = spi_master_resume(pl022->master);
+       if (!ret)
+               dev_dbg(dev, "resumed\n");
+
+       return ret;
+}
+#endif
+
+#ifdef CONFIG_PM
+static int pl022_runtime_suspend(struct device *dev)
+{
+       struct pl022 *pl022 = dev_get_drvdata(dev);
+
+       clk_disable_unprepare(pl022->clk);
+       pinctrl_pm_select_idle_state(dev);
+
+       return 0;
+}
+
+static int pl022_runtime_resume(struct device *dev)
+{
+       struct pl022 *pl022 = dev_get_drvdata(dev);
+
+       pinctrl_pm_select_default_state(dev);
+       clk_prepare_enable(pl022->clk);
+
+       return 0;
+}
+#endif
+
+static const struct dev_pm_ops pl022_dev_pm_ops = {
+       SET_SYSTEM_SLEEP_PM_OPS(pl022_suspend, pl022_resume)
+       SET_RUNTIME_PM_OPS(pl022_runtime_suspend, pl022_runtime_resume, NULL)
+};
+
+static struct vendor_data vendor_arm = {
+       .fifodepth = 8,
+       .max_bpw = 16,
+       .unidir = false,
+       .extended_cr = false,
+       .pl023 = false,
+       .loopback = true,
+       .internal_cs_ctrl = false,
+};
+
+static struct vendor_data vendor_st = {
+       .fifodepth = 32,
+       .max_bpw = 32,
+       .unidir = false,
+       .extended_cr = true,
+       .pl023 = false,
+       .loopback = true,
+       .internal_cs_ctrl = false,
+};
+
+static struct vendor_data vendor_st_pl023 = {
+       .fifodepth = 32,
+       .max_bpw = 32,
+       .unidir = false,
+       .extended_cr = true,
+       .pl023 = true,
+       .loopback = false,
+       .internal_cs_ctrl = false,
+};
+
+static struct vendor_data vendor_lsi = {
+       .fifodepth = 8,
+       .max_bpw = 16,
+       .unidir = false,
+       .extended_cr = false,
+       .pl023 = false,
+       .loopback = true,
+       .internal_cs_ctrl = true,
+};
+
+static const struct amba_id pl022_ids[] = {
+       {
+               /*
+                * ARM PL022 variant, this has a 16bit wide
+                * and 8 locations deep TX/RX FIFO
+                */
+               .id     = 0x00041022,
+               .mask   = 0x000fffff,
+               .data   = &vendor_arm,
+       },
+       {
+               /*
+                * ST Micro derivative, this has 32bit wide
+                * and 32 locations deep TX/RX FIFO
+                */
+               .id     = 0x01080022,
+               .mask   = 0xffffffff,
+               .data   = &vendor_st,
+       },
+       {
+               /*
+                * ST-Ericsson derivative "PL023" (this is not
+                * an official ARM number), this is a PL022 SSP block
+                * stripped to SPI mode only, it has 32bit wide
+                * and 32 locations deep TX/RX FIFO but no extended
+                * CR0/CR1 register
+                */
+               .id     = 0x00080023,
+               .mask   = 0xffffffff,
+               .data   = &vendor_st_pl023,
+       },
+       {
+               /*
+                * PL022 variant that has a chip select control register whih
+                * allows control of 5 output signals nCS[0:4].
+                */
+               .id     = 0x000b6022,
+               .mask   = 0x000fffff,
+               .data   = &vendor_lsi,
+       },
+       { 0, 0 },
+};
+
+MODULE_DEVICE_TABLE(amba, pl022_ids);
+
+static struct amba_driver pl022_driver = {
+       .drv = {
+               .name   = "ssp-pl022",
+               .pm     = &pl022_dev_pm_ops,
+       },
+       .id_table       = pl022_ids,
+       .probe          = pl022_probe,
+       .remove         = pl022_remove,
+};
+
+static int __init pl022_init(void)
+{
+       return amba_driver_register(&pl022_driver);
+}
+subsys_initcall(pl022_init);
+
+static void __exit pl022_exit(void)
+{
+       amba_driver_unregister(&pl022_driver);
+}
+module_exit(pl022_exit);
+
+MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
+MODULE_DESCRIPTION("PL022 SSP Controller Driver");
+MODULE_LICENSE("GPL");