spi: dw: Add core suffix to the DW APB SSI core source file
authorSerge Semin <Sergey.Semin@baikalelectronics.ru>
Fri, 29 May 2020 13:11:58 +0000 (16:11 +0300)
committerMark Brown <broonie@kernel.org>
Fri, 29 May 2020 14:55:49 +0000 (15:55 +0100)
Generic DMA support is going to be part of the DW APB SSI core object.
In order to preserve the kernel loadable module name as spi-dw.ko, let's
add the "-core" suffix to the object with generic DW APB SSI code and
build it into the target spi-dw.ko driver.

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Cc: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Link: https://lore.kernel.org/r/20200529131205.31838-10-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
drivers/spi/Makefile
drivers/spi/spi-dw-core.c [new file with mode: 0644]
drivers/spi/spi-dw.c [deleted file]

index 889368f4ad53b22e83d183d08872750a5ace732e..840a5a1c655ecea6ac8104494879f75001396588 100644 (file)
@@ -36,6 +36,7 @@ obj-$(CONFIG_SPI_COLDFIRE_QSPI)               += spi-coldfire-qspi.o
 obj-$(CONFIG_SPI_DAVINCI)              += spi-davinci.o
 obj-$(CONFIG_SPI_DLN2)                 += spi-dln2.o
 obj-$(CONFIG_SPI_DESIGNWARE)           += spi-dw.o
+spi-dw-y                               := spi-dw-core.o
 obj-$(CONFIG_SPI_DW_MMIO)              += spi-dw-mmio.o
 obj-$(CONFIG_SPI_DW_PCI)               += spi-dw-midpci.o
 spi-dw-midpci-objs                     := spi-dw-pci.o spi-dw-mid.o
diff --git a/drivers/spi/spi-dw-core.c b/drivers/spi/spi-dw-core.c
new file mode 100644 (file)
index 0000000..1f1a353
--- /dev/null
@@ -0,0 +1,577 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Designware SPI core controller driver (refer pxa2xx_spi.c)
+ *
+ * Copyright (c) 2009, Intel Corporation.
+ */
+
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/highmem.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+
+#include "spi-dw.h"
+
+#ifdef CONFIG_DEBUG_FS
+#include <linux/debugfs.h>
+#endif
+
+/* Slave spi_dev related */
+struct chip_data {
+       u8 tmode;               /* TR/TO/RO/EEPROM */
+       u8 type;                /* SPI/SSP/MicroWire */
+
+       u16 clk_div;            /* baud rate divider */
+       u32 speed_hz;           /* baud rate */
+};
+
+#ifdef CONFIG_DEBUG_FS
+#define SPI_REGS_BUFSIZE       1024
+static ssize_t dw_spi_show_regs(struct file *file, char __user *user_buf,
+               size_t count, loff_t *ppos)
+{
+       struct dw_spi *dws = file->private_data;
+       char *buf;
+       u32 len = 0;
+       ssize_t ret;
+
+       buf = kzalloc(SPI_REGS_BUFSIZE, GFP_KERNEL);
+       if (!buf)
+               return 0;
+
+       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
+                       "%s registers:\n", dev_name(&dws->master->dev));
+       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
+                       "=================================\n");
+       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
+                       "CTRLR0: \t0x%08x\n", dw_readl(dws, DW_SPI_CTRLR0));
+       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
+                       "CTRLR1: \t0x%08x\n", dw_readl(dws, DW_SPI_CTRLR1));
+       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
+                       "SSIENR: \t0x%08x\n", dw_readl(dws, DW_SPI_SSIENR));
+       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
+                       "SER: \t\t0x%08x\n", dw_readl(dws, DW_SPI_SER));
+       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
+                       "BAUDR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_BAUDR));
+       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
+                       "TXFTLR: \t0x%08x\n", dw_readl(dws, DW_SPI_TXFTLR));
+       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
+                       "RXFTLR: \t0x%08x\n", dw_readl(dws, DW_SPI_RXFTLR));
+       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
+                       "TXFLR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_TXFLR));
+       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
+                       "RXFLR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_RXFLR));
+       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
+                       "SR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_SR));
+       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
+                       "IMR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_IMR));
+       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
+                       "ISR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_ISR));
+       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
+                       "DMACR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_DMACR));
+       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
+                       "DMATDLR: \t0x%08x\n", dw_readl(dws, DW_SPI_DMATDLR));
+       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
+                       "DMARDLR: \t0x%08x\n", dw_readl(dws, DW_SPI_DMARDLR));
+       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
+                       "=================================\n");
+
+       ret = simple_read_from_buffer(user_buf, count, ppos, buf, len);
+       kfree(buf);
+       return ret;
+}
+
+static const struct file_operations dw_spi_regs_ops = {
+       .owner          = THIS_MODULE,
+       .open           = simple_open,
+       .read           = dw_spi_show_regs,
+       .llseek         = default_llseek,
+};
+
+static int dw_spi_debugfs_init(struct dw_spi *dws)
+{
+       char name[32];
+
+       snprintf(name, 32, "dw_spi%d", dws->master->bus_num);
+       dws->debugfs = debugfs_create_dir(name, NULL);
+       if (!dws->debugfs)
+               return -ENOMEM;
+
+       debugfs_create_file("registers", S_IFREG | S_IRUGO,
+               dws->debugfs, (void *)dws, &dw_spi_regs_ops);
+       return 0;
+}
+
+static void dw_spi_debugfs_remove(struct dw_spi *dws)
+{
+       debugfs_remove_recursive(dws->debugfs);
+}
+
+#else
+static inline int dw_spi_debugfs_init(struct dw_spi *dws)
+{
+       return 0;
+}
+
+static inline void dw_spi_debugfs_remove(struct dw_spi *dws)
+{
+}
+#endif /* CONFIG_DEBUG_FS */
+
+void dw_spi_set_cs(struct spi_device *spi, bool enable)
+{
+       struct dw_spi *dws = spi_controller_get_devdata(spi->controller);
+       bool cs_high = !!(spi->mode & SPI_CS_HIGH);
+
+       /*
+        * DW SPI controller demands any native CS being set in order to
+        * proceed with data transfer. So in order to activate the SPI
+        * communications we must set a corresponding bit in the Slave
+        * Enable register no matter whether the SPI core is configured to
+        * support active-high or active-low CS level.
+        */
+       if (cs_high == enable)
+               dw_writel(dws, DW_SPI_SER, BIT(spi->chip_select));
+       else if (dws->cs_override)
+               dw_writel(dws, DW_SPI_SER, 0);
+}
+EXPORT_SYMBOL_GPL(dw_spi_set_cs);
+
+/* Return the max entries we can fill into tx fifo */
+static inline u32 tx_max(struct dw_spi *dws)
+{
+       u32 tx_left, tx_room, rxtx_gap;
+
+       tx_left = (dws->tx_end - dws->tx) / dws->n_bytes;
+       tx_room = dws->fifo_len - dw_readl(dws, DW_SPI_TXFLR);
+
+       /*
+        * Another concern is about the tx/rx mismatch, we
+        * though to use (dws->fifo_len - rxflr - txflr) as
+        * one maximum value for tx, but it doesn't cover the
+        * data which is out of tx/rx fifo and inside the
+        * shift registers. So a control from sw point of
+        * view is taken.
+        */
+       rxtx_gap =  ((dws->rx_end - dws->rx) - (dws->tx_end - dws->tx))
+                       / dws->n_bytes;
+
+       return min3(tx_left, tx_room, (u32) (dws->fifo_len - rxtx_gap));
+}
+
+/* Return the max entries we should read out of rx fifo */
+static inline u32 rx_max(struct dw_spi *dws)
+{
+       u32 rx_left = (dws->rx_end - dws->rx) / dws->n_bytes;
+
+       return min_t(u32, rx_left, dw_readl(dws, DW_SPI_RXFLR));
+}
+
+static void dw_writer(struct dw_spi *dws)
+{
+       u32 max;
+       u16 txw = 0;
+
+       spin_lock(&dws->buf_lock);
+       max = tx_max(dws);
+       while (max--) {
+               /* Set the tx word if the transfer's original "tx" is not null */
+               if (dws->tx_end - dws->len) {
+                       if (dws->n_bytes == 1)
+                               txw = *(u8 *)(dws->tx);
+                       else
+                               txw = *(u16 *)(dws->tx);
+               }
+               dw_write_io_reg(dws, DW_SPI_DR, txw);
+               dws->tx += dws->n_bytes;
+       }
+       spin_unlock(&dws->buf_lock);
+}
+
+static void dw_reader(struct dw_spi *dws)
+{
+       u32 max;
+       u16 rxw;
+
+       spin_lock(&dws->buf_lock);
+       max = rx_max(dws);
+       while (max--) {
+               rxw = dw_read_io_reg(dws, DW_SPI_DR);
+               /* Care rx only if the transfer's original "rx" is not null */
+               if (dws->rx_end - dws->len) {
+                       if (dws->n_bytes == 1)
+                               *(u8 *)(dws->rx) = rxw;
+                       else
+                               *(u16 *)(dws->rx) = rxw;
+               }
+               dws->rx += dws->n_bytes;
+       }
+       spin_unlock(&dws->buf_lock);
+}
+
+static void int_error_stop(struct dw_spi *dws, const char *msg)
+{
+       spi_reset_chip(dws);
+
+       dev_err(&dws->master->dev, "%s\n", msg);
+       dws->master->cur_msg->status = -EIO;
+       spi_finalize_current_transfer(dws->master);
+}
+
+static irqreturn_t interrupt_transfer(struct dw_spi *dws)
+{
+       u16 irq_status = dw_readl(dws, DW_SPI_ISR);
+
+       /* Error handling */
+       if (irq_status & (SPI_INT_TXOI | SPI_INT_RXOI | SPI_INT_RXUI)) {
+               dw_readl(dws, DW_SPI_ICR);
+               int_error_stop(dws, "interrupt_transfer: fifo overrun/underrun");
+               return IRQ_HANDLED;
+       }
+
+       dw_reader(dws);
+       if (dws->rx_end == dws->rx) {
+               spi_mask_intr(dws, SPI_INT_TXEI);
+               spi_finalize_current_transfer(dws->master);
+               return IRQ_HANDLED;
+       }
+       if (irq_status & SPI_INT_TXEI) {
+               spi_mask_intr(dws, SPI_INT_TXEI);
+               dw_writer(dws);
+               /* Enable TX irq always, it will be disabled when RX finished */
+               spi_umask_intr(dws, SPI_INT_TXEI);
+       }
+
+       return IRQ_HANDLED;
+}
+
+static irqreturn_t dw_spi_irq(int irq, void *dev_id)
+{
+       struct spi_controller *master = dev_id;
+       struct dw_spi *dws = spi_controller_get_devdata(master);
+       u16 irq_status = dw_readl(dws, DW_SPI_ISR) & 0x3f;
+
+       if (!irq_status)
+               return IRQ_NONE;
+
+       if (!master->cur_msg) {
+               spi_mask_intr(dws, SPI_INT_TXEI);
+               return IRQ_HANDLED;
+       }
+
+       return dws->transfer_handler(dws);
+}
+
+/* Configure CTRLR0 for DW_apb_ssi */
+u32 dw_spi_update_cr0(struct spi_controller *master, struct spi_device *spi,
+                     struct spi_transfer *transfer)
+{
+       struct chip_data *chip = spi_get_ctldata(spi);
+       u32 cr0;
+
+       /* Default SPI mode is SCPOL = 0, SCPH = 0 */
+       cr0 = (transfer->bits_per_word - 1)
+               | (chip->type << SPI_FRF_OFFSET)
+               | ((((spi->mode & SPI_CPOL) ? 1 : 0) << SPI_SCOL_OFFSET) |
+                  (((spi->mode & SPI_CPHA) ? 1 : 0) << SPI_SCPH_OFFSET) |
+                  (((spi->mode & SPI_LOOP) ? 1 : 0) << SPI_SRL_OFFSET))
+               | (chip->tmode << SPI_TMOD_OFFSET);
+
+       return cr0;
+}
+EXPORT_SYMBOL_GPL(dw_spi_update_cr0);
+
+/* Configure CTRLR0 for DWC_ssi */
+u32 dw_spi_update_cr0_v1_01a(struct spi_controller *master,
+                            struct spi_device *spi,
+                            struct spi_transfer *transfer)
+{
+       struct chip_data *chip = spi_get_ctldata(spi);
+       u32 cr0;
+
+       /* CTRLR0[ 4: 0] Data Frame Size */
+       cr0 = (transfer->bits_per_word - 1);
+
+       /* CTRLR0[ 7: 6] Frame Format */
+       cr0 |= chip->type << DWC_SSI_CTRLR0_FRF_OFFSET;
+
+       /*
+        * SPI mode (SCPOL|SCPH)
+        * CTRLR0[ 8] Serial Clock Phase
+        * CTRLR0[ 9] Serial Clock Polarity
+        */
+       cr0 |= ((spi->mode & SPI_CPOL) ? 1 : 0) << DWC_SSI_CTRLR0_SCPOL_OFFSET;
+       cr0 |= ((spi->mode & SPI_CPHA) ? 1 : 0) << DWC_SSI_CTRLR0_SCPH_OFFSET;
+
+       /* CTRLR0[11:10] Transfer Mode */
+       cr0 |= chip->tmode << DWC_SSI_CTRLR0_TMOD_OFFSET;
+
+       /* CTRLR0[13] Shift Register Loop */
+       cr0 |= ((spi->mode & SPI_LOOP) ? 1 : 0) << DWC_SSI_CTRLR0_SRL_OFFSET;
+
+       return cr0;
+}
+EXPORT_SYMBOL_GPL(dw_spi_update_cr0_v1_01a);
+
+static int dw_spi_transfer_one(struct spi_controller *master,
+               struct spi_device *spi, struct spi_transfer *transfer)
+{
+       struct dw_spi *dws = spi_controller_get_devdata(master);
+       struct chip_data *chip = spi_get_ctldata(spi);
+       unsigned long flags;
+       u8 imask = 0;
+       u16 txlevel = 0;
+       u32 cr0;
+       int ret;
+
+       dws->dma_mapped = 0;
+       spin_lock_irqsave(&dws->buf_lock, flags);
+       dws->tx = (void *)transfer->tx_buf;
+       dws->tx_end = dws->tx + transfer->len;
+       dws->rx = transfer->rx_buf;
+       dws->rx_end = dws->rx + transfer->len;
+       dws->len = transfer->len;
+       spin_unlock_irqrestore(&dws->buf_lock, flags);
+
+       /* Ensure dw->rx and dw->rx_end are visible */
+       smp_mb();
+
+       spi_enable_chip(dws, 0);
+
+       /* Handle per transfer options for bpw and speed */
+       if (transfer->speed_hz != dws->current_freq) {
+               if (transfer->speed_hz != chip->speed_hz) {
+                       /* clk_div doesn't support odd number */
+                       chip->clk_div = (DIV_ROUND_UP(dws->max_freq, transfer->speed_hz) + 1) & 0xfffe;
+                       chip->speed_hz = transfer->speed_hz;
+               }
+               dws->current_freq = transfer->speed_hz;
+               spi_set_clk(dws, chip->clk_div);
+       }
+
+       transfer->effective_speed_hz = dws->max_freq / chip->clk_div;
+       dws->n_bytes = DIV_ROUND_UP(transfer->bits_per_word, BITS_PER_BYTE);
+
+       cr0 = dws->update_cr0(master, spi, transfer);
+       dw_writel(dws, DW_SPI_CTRLR0, cr0);
+
+       /* Check if current transfer is a DMA transaction */
+       if (master->can_dma && master->can_dma(master, spi, transfer))
+               dws->dma_mapped = master->cur_msg_mapped;
+
+       /* For poll mode just disable all interrupts */
+       spi_mask_intr(dws, 0xff);
+
+       /*
+        * Interrupt mode
+        * we only need set the TXEI IRQ, as TX/RX always happen syncronizely
+        */
+       if (dws->dma_mapped) {
+               ret = dws->dma_ops->dma_setup(dws, transfer);
+               if (ret < 0) {
+                       spi_enable_chip(dws, 1);
+                       return ret;
+               }
+       } else {
+               txlevel = min_t(u16, dws->fifo_len / 2, dws->len / dws->n_bytes);
+               dw_writel(dws, DW_SPI_TXFTLR, txlevel);
+
+               /* Set the interrupt mask */
+               imask |= SPI_INT_TXEI | SPI_INT_TXOI |
+                        SPI_INT_RXUI | SPI_INT_RXOI;
+               spi_umask_intr(dws, imask);
+
+               dws->transfer_handler = interrupt_transfer;
+       }
+
+       spi_enable_chip(dws, 1);
+
+       if (dws->dma_mapped)
+               return dws->dma_ops->dma_transfer(dws, transfer);
+
+       return 1;
+}
+
+static void dw_spi_handle_err(struct spi_controller *master,
+               struct spi_message *msg)
+{
+       struct dw_spi *dws = spi_controller_get_devdata(master);
+
+       if (dws->dma_mapped)
+               dws->dma_ops->dma_stop(dws);
+
+       spi_reset_chip(dws);
+}
+
+/* This may be called twice for each spi dev */
+static int dw_spi_setup(struct spi_device *spi)
+{
+       struct chip_data *chip;
+
+       /* Only alloc on first setup */
+       chip = spi_get_ctldata(spi);
+       if (!chip) {
+               chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
+               if (!chip)
+                       return -ENOMEM;
+               spi_set_ctldata(spi, chip);
+       }
+
+       chip->tmode = SPI_TMOD_TR;
+
+       return 0;
+}
+
+static void dw_spi_cleanup(struct spi_device *spi)
+{
+       struct chip_data *chip = spi_get_ctldata(spi);
+
+       kfree(chip);
+       spi_set_ctldata(spi, NULL);
+}
+
+/* Restart the controller, disable all interrupts, clean rx fifo */
+static void spi_hw_init(struct device *dev, struct dw_spi *dws)
+{
+       spi_reset_chip(dws);
+
+       /*
+        * Try to detect the FIFO depth if not set by interface driver,
+        * the depth could be from 2 to 256 from HW spec
+        */
+       if (!dws->fifo_len) {
+               u32 fifo;
+
+               for (fifo = 1; fifo < 256; fifo++) {
+                       dw_writel(dws, DW_SPI_TXFTLR, fifo);
+                       if (fifo != dw_readl(dws, DW_SPI_TXFTLR))
+                               break;
+               }
+               dw_writel(dws, DW_SPI_TXFTLR, 0);
+
+               dws->fifo_len = (fifo == 1) ? 0 : fifo;
+               dev_dbg(dev, "Detected FIFO size: %u bytes\n", dws->fifo_len);
+       }
+
+       /* enable HW fixup for explicit CS deselect for Amazon's alpine chip */
+       if (dws->cs_override)
+               dw_writel(dws, DW_SPI_CS_OVERRIDE, 0xF);
+}
+
+int dw_spi_add_host(struct device *dev, struct dw_spi *dws)
+{
+       struct spi_controller *master;
+       int ret;
+
+       if (!dws)
+               return -EINVAL;
+
+       master = spi_alloc_master(dev, 0);
+       if (!master)
+               return -ENOMEM;
+
+       dws->master = master;
+       dws->type = SSI_MOTO_SPI;
+       dws->dma_addr = (dma_addr_t)(dws->paddr + DW_SPI_DR);
+       spin_lock_init(&dws->buf_lock);
+
+       spi_controller_set_devdata(master, dws);
+
+       ret = request_irq(dws->irq, dw_spi_irq, IRQF_SHARED, dev_name(dev),
+                         master);
+       if (ret < 0) {
+               dev_err(dev, "can not get IRQ\n");
+               goto err_free_master;
+       }
+
+       master->use_gpio_descriptors = true;
+       master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP;
+       master->bits_per_word_mask =  SPI_BPW_RANGE_MASK(4, 16);
+       master->bus_num = dws->bus_num;
+       master->num_chipselect = dws->num_cs;
+       master->setup = dw_spi_setup;
+       master->cleanup = dw_spi_cleanup;
+       master->set_cs = dw_spi_set_cs;
+       master->transfer_one = dw_spi_transfer_one;
+       master->handle_err = dw_spi_handle_err;
+       master->max_speed_hz = dws->max_freq;
+       master->dev.of_node = dev->of_node;
+       master->dev.fwnode = dev->fwnode;
+       master->flags = SPI_MASTER_GPIO_SS;
+       master->auto_runtime_pm = true;
+
+       if (dws->set_cs)
+               master->set_cs = dws->set_cs;
+
+       /* Basic HW init */
+       spi_hw_init(dev, dws);
+
+       if (dws->dma_ops && dws->dma_ops->dma_init) {
+               ret = dws->dma_ops->dma_init(dev, dws);
+               if (ret) {
+                       dev_warn(dev, "DMA init failed\n");
+               } else {
+                       master->can_dma = dws->dma_ops->can_dma;
+                       master->flags |= SPI_CONTROLLER_MUST_TX;
+               }
+       }
+
+       ret = devm_spi_register_controller(dev, master);
+       if (ret) {
+               dev_err(&master->dev, "problem registering spi master\n");
+               goto err_dma_exit;
+       }
+
+       dw_spi_debugfs_init(dws);
+       return 0;
+
+err_dma_exit:
+       if (dws->dma_ops && dws->dma_ops->dma_exit)
+               dws->dma_ops->dma_exit(dws);
+       spi_enable_chip(dws, 0);
+       free_irq(dws->irq, master);
+err_free_master:
+       spi_controller_put(master);
+       return ret;
+}
+EXPORT_SYMBOL_GPL(dw_spi_add_host);
+
+void dw_spi_remove_host(struct dw_spi *dws)
+{
+       dw_spi_debugfs_remove(dws);
+
+       if (dws->dma_ops && dws->dma_ops->dma_exit)
+               dws->dma_ops->dma_exit(dws);
+
+       spi_shutdown_chip(dws);
+
+       free_irq(dws->irq, dws->master);
+}
+EXPORT_SYMBOL_GPL(dw_spi_remove_host);
+
+int dw_spi_suspend_host(struct dw_spi *dws)
+{
+       int ret;
+
+       ret = spi_controller_suspend(dws->master);
+       if (ret)
+               return ret;
+
+       spi_shutdown_chip(dws);
+       return 0;
+}
+EXPORT_SYMBOL_GPL(dw_spi_suspend_host);
+
+int dw_spi_resume_host(struct dw_spi *dws)
+{
+       spi_hw_init(&dws->master->dev, dws);
+       return spi_controller_resume(dws->master);
+}
+EXPORT_SYMBOL_GPL(dw_spi_resume_host);
+
+MODULE_AUTHOR("Feng Tang <feng.tang@intel.com>");
+MODULE_DESCRIPTION("Driver for DesignWare SPI controller core");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c
deleted file mode 100644 (file)
index 1f1a353..0000000
+++ /dev/null
@@ -1,577 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Designware SPI core controller driver (refer pxa2xx_spi.c)
- *
- * Copyright (c) 2009, Intel Corporation.
- */
-
-#include <linux/dma-mapping.h>
-#include <linux/interrupt.h>
-#include <linux/module.h>
-#include <linux/highmem.h>
-#include <linux/delay.h>
-#include <linux/slab.h>
-#include <linux/spi/spi.h>
-
-#include "spi-dw.h"
-
-#ifdef CONFIG_DEBUG_FS
-#include <linux/debugfs.h>
-#endif
-
-/* Slave spi_dev related */
-struct chip_data {
-       u8 tmode;               /* TR/TO/RO/EEPROM */
-       u8 type;                /* SPI/SSP/MicroWire */
-
-       u16 clk_div;            /* baud rate divider */
-       u32 speed_hz;           /* baud rate */
-};
-
-#ifdef CONFIG_DEBUG_FS
-#define SPI_REGS_BUFSIZE       1024
-static ssize_t dw_spi_show_regs(struct file *file, char __user *user_buf,
-               size_t count, loff_t *ppos)
-{
-       struct dw_spi *dws = file->private_data;
-       char *buf;
-       u32 len = 0;
-       ssize_t ret;
-
-       buf = kzalloc(SPI_REGS_BUFSIZE, GFP_KERNEL);
-       if (!buf)
-               return 0;
-
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "%s registers:\n", dev_name(&dws->master->dev));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "=================================\n");
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "CTRLR0: \t0x%08x\n", dw_readl(dws, DW_SPI_CTRLR0));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "CTRLR1: \t0x%08x\n", dw_readl(dws, DW_SPI_CTRLR1));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "SSIENR: \t0x%08x\n", dw_readl(dws, DW_SPI_SSIENR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "SER: \t\t0x%08x\n", dw_readl(dws, DW_SPI_SER));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "BAUDR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_BAUDR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "TXFTLR: \t0x%08x\n", dw_readl(dws, DW_SPI_TXFTLR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "RXFTLR: \t0x%08x\n", dw_readl(dws, DW_SPI_RXFTLR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "TXFLR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_TXFLR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "RXFLR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_RXFLR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "SR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_SR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "IMR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_IMR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "ISR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_ISR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "DMACR: \t\t0x%08x\n", dw_readl(dws, DW_SPI_DMACR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "DMATDLR: \t0x%08x\n", dw_readl(dws, DW_SPI_DMATDLR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "DMARDLR: \t0x%08x\n", dw_readl(dws, DW_SPI_DMARDLR));
-       len += scnprintf(buf + len, SPI_REGS_BUFSIZE - len,
-                       "=================================\n");
-
-       ret = simple_read_from_buffer(user_buf, count, ppos, buf, len);
-       kfree(buf);
-       return ret;
-}
-
-static const struct file_operations dw_spi_regs_ops = {
-       .owner          = THIS_MODULE,
-       .open           = simple_open,
-       .read           = dw_spi_show_regs,
-       .llseek         = default_llseek,
-};
-
-static int dw_spi_debugfs_init(struct dw_spi *dws)
-{
-       char name[32];
-
-       snprintf(name, 32, "dw_spi%d", dws->master->bus_num);
-       dws->debugfs = debugfs_create_dir(name, NULL);
-       if (!dws->debugfs)
-               return -ENOMEM;
-
-       debugfs_create_file("registers", S_IFREG | S_IRUGO,
-               dws->debugfs, (void *)dws, &dw_spi_regs_ops);
-       return 0;
-}
-
-static void dw_spi_debugfs_remove(struct dw_spi *dws)
-{
-       debugfs_remove_recursive(dws->debugfs);
-}
-
-#else
-static inline int dw_spi_debugfs_init(struct dw_spi *dws)
-{
-       return 0;
-}
-
-static inline void dw_spi_debugfs_remove(struct dw_spi *dws)
-{
-}
-#endif /* CONFIG_DEBUG_FS */
-
-void dw_spi_set_cs(struct spi_device *spi, bool enable)
-{
-       struct dw_spi *dws = spi_controller_get_devdata(spi->controller);
-       bool cs_high = !!(spi->mode & SPI_CS_HIGH);
-
-       /*
-        * DW SPI controller demands any native CS being set in order to
-        * proceed with data transfer. So in order to activate the SPI
-        * communications we must set a corresponding bit in the Slave
-        * Enable register no matter whether the SPI core is configured to
-        * support active-high or active-low CS level.
-        */
-       if (cs_high == enable)
-               dw_writel(dws, DW_SPI_SER, BIT(spi->chip_select));
-       else if (dws->cs_override)
-               dw_writel(dws, DW_SPI_SER, 0);
-}
-EXPORT_SYMBOL_GPL(dw_spi_set_cs);
-
-/* Return the max entries we can fill into tx fifo */
-static inline u32 tx_max(struct dw_spi *dws)
-{
-       u32 tx_left, tx_room, rxtx_gap;
-
-       tx_left = (dws->tx_end - dws->tx) / dws->n_bytes;
-       tx_room = dws->fifo_len - dw_readl(dws, DW_SPI_TXFLR);
-
-       /*
-        * Another concern is about the tx/rx mismatch, we
-        * though to use (dws->fifo_len - rxflr - txflr) as
-        * one maximum value for tx, but it doesn't cover the
-        * data which is out of tx/rx fifo and inside the
-        * shift registers. So a control from sw point of
-        * view is taken.
-        */
-       rxtx_gap =  ((dws->rx_end - dws->rx) - (dws->tx_end - dws->tx))
-                       / dws->n_bytes;
-
-       return min3(tx_left, tx_room, (u32) (dws->fifo_len - rxtx_gap));
-}
-
-/* Return the max entries we should read out of rx fifo */
-static inline u32 rx_max(struct dw_spi *dws)
-{
-       u32 rx_left = (dws->rx_end - dws->rx) / dws->n_bytes;
-
-       return min_t(u32, rx_left, dw_readl(dws, DW_SPI_RXFLR));
-}
-
-static void dw_writer(struct dw_spi *dws)
-{
-       u32 max;
-       u16 txw = 0;
-
-       spin_lock(&dws->buf_lock);
-       max = tx_max(dws);
-       while (max--) {
-               /* Set the tx word if the transfer's original "tx" is not null */
-               if (dws->tx_end - dws->len) {
-                       if (dws->n_bytes == 1)
-                               txw = *(u8 *)(dws->tx);
-                       else
-                               txw = *(u16 *)(dws->tx);
-               }
-               dw_write_io_reg(dws, DW_SPI_DR, txw);
-               dws->tx += dws->n_bytes;
-       }
-       spin_unlock(&dws->buf_lock);
-}
-
-static void dw_reader(struct dw_spi *dws)
-{
-       u32 max;
-       u16 rxw;
-
-       spin_lock(&dws->buf_lock);
-       max = rx_max(dws);
-       while (max--) {
-               rxw = dw_read_io_reg(dws, DW_SPI_DR);
-               /* Care rx only if the transfer's original "rx" is not null */
-               if (dws->rx_end - dws->len) {
-                       if (dws->n_bytes == 1)
-                               *(u8 *)(dws->rx) = rxw;
-                       else
-                               *(u16 *)(dws->rx) = rxw;
-               }
-               dws->rx += dws->n_bytes;
-       }
-       spin_unlock(&dws->buf_lock);
-}
-
-static void int_error_stop(struct dw_spi *dws, const char *msg)
-{
-       spi_reset_chip(dws);
-
-       dev_err(&dws->master->dev, "%s\n", msg);
-       dws->master->cur_msg->status = -EIO;
-       spi_finalize_current_transfer(dws->master);
-}
-
-static irqreturn_t interrupt_transfer(struct dw_spi *dws)
-{
-       u16 irq_status = dw_readl(dws, DW_SPI_ISR);
-
-       /* Error handling */
-       if (irq_status & (SPI_INT_TXOI | SPI_INT_RXOI | SPI_INT_RXUI)) {
-               dw_readl(dws, DW_SPI_ICR);
-               int_error_stop(dws, "interrupt_transfer: fifo overrun/underrun");
-               return IRQ_HANDLED;
-       }
-
-       dw_reader(dws);
-       if (dws->rx_end == dws->rx) {
-               spi_mask_intr(dws, SPI_INT_TXEI);
-               spi_finalize_current_transfer(dws->master);
-               return IRQ_HANDLED;
-       }
-       if (irq_status & SPI_INT_TXEI) {
-               spi_mask_intr(dws, SPI_INT_TXEI);
-               dw_writer(dws);
-               /* Enable TX irq always, it will be disabled when RX finished */
-               spi_umask_intr(dws, SPI_INT_TXEI);
-       }
-
-       return IRQ_HANDLED;
-}
-
-static irqreturn_t dw_spi_irq(int irq, void *dev_id)
-{
-       struct spi_controller *master = dev_id;
-       struct dw_spi *dws = spi_controller_get_devdata(master);
-       u16 irq_status = dw_readl(dws, DW_SPI_ISR) & 0x3f;
-
-       if (!irq_status)
-               return IRQ_NONE;
-
-       if (!master->cur_msg) {
-               spi_mask_intr(dws, SPI_INT_TXEI);
-               return IRQ_HANDLED;
-       }
-
-       return dws->transfer_handler(dws);
-}
-
-/* Configure CTRLR0 for DW_apb_ssi */
-u32 dw_spi_update_cr0(struct spi_controller *master, struct spi_device *spi,
-                     struct spi_transfer *transfer)
-{
-       struct chip_data *chip = spi_get_ctldata(spi);
-       u32 cr0;
-
-       /* Default SPI mode is SCPOL = 0, SCPH = 0 */
-       cr0 = (transfer->bits_per_word - 1)
-               | (chip->type << SPI_FRF_OFFSET)
-               | ((((spi->mode & SPI_CPOL) ? 1 : 0) << SPI_SCOL_OFFSET) |
-                  (((spi->mode & SPI_CPHA) ? 1 : 0) << SPI_SCPH_OFFSET) |
-                  (((spi->mode & SPI_LOOP) ? 1 : 0) << SPI_SRL_OFFSET))
-               | (chip->tmode << SPI_TMOD_OFFSET);
-
-       return cr0;
-}
-EXPORT_SYMBOL_GPL(dw_spi_update_cr0);
-
-/* Configure CTRLR0 for DWC_ssi */
-u32 dw_spi_update_cr0_v1_01a(struct spi_controller *master,
-                            struct spi_device *spi,
-                            struct spi_transfer *transfer)
-{
-       struct chip_data *chip = spi_get_ctldata(spi);
-       u32 cr0;
-
-       /* CTRLR0[ 4: 0] Data Frame Size */
-       cr0 = (transfer->bits_per_word - 1);
-
-       /* CTRLR0[ 7: 6] Frame Format */
-       cr0 |= chip->type << DWC_SSI_CTRLR0_FRF_OFFSET;
-
-       /*
-        * SPI mode (SCPOL|SCPH)
-        * CTRLR0[ 8] Serial Clock Phase
-        * CTRLR0[ 9] Serial Clock Polarity
-        */
-       cr0 |= ((spi->mode & SPI_CPOL) ? 1 : 0) << DWC_SSI_CTRLR0_SCPOL_OFFSET;
-       cr0 |= ((spi->mode & SPI_CPHA) ? 1 : 0) << DWC_SSI_CTRLR0_SCPH_OFFSET;
-
-       /* CTRLR0[11:10] Transfer Mode */
-       cr0 |= chip->tmode << DWC_SSI_CTRLR0_TMOD_OFFSET;
-
-       /* CTRLR0[13] Shift Register Loop */
-       cr0 |= ((spi->mode & SPI_LOOP) ? 1 : 0) << DWC_SSI_CTRLR0_SRL_OFFSET;
-
-       return cr0;
-}
-EXPORT_SYMBOL_GPL(dw_spi_update_cr0_v1_01a);
-
-static int dw_spi_transfer_one(struct spi_controller *master,
-               struct spi_device *spi, struct spi_transfer *transfer)
-{
-       struct dw_spi *dws = spi_controller_get_devdata(master);
-       struct chip_data *chip = spi_get_ctldata(spi);
-       unsigned long flags;
-       u8 imask = 0;
-       u16 txlevel = 0;
-       u32 cr0;
-       int ret;
-
-       dws->dma_mapped = 0;
-       spin_lock_irqsave(&dws->buf_lock, flags);
-       dws->tx = (void *)transfer->tx_buf;
-       dws->tx_end = dws->tx + transfer->len;
-       dws->rx = transfer->rx_buf;
-       dws->rx_end = dws->rx + transfer->len;
-       dws->len = transfer->len;
-       spin_unlock_irqrestore(&dws->buf_lock, flags);
-
-       /* Ensure dw->rx and dw->rx_end are visible */
-       smp_mb();
-
-       spi_enable_chip(dws, 0);
-
-       /* Handle per transfer options for bpw and speed */
-       if (transfer->speed_hz != dws->current_freq) {
-               if (transfer->speed_hz != chip->speed_hz) {
-                       /* clk_div doesn't support odd number */
-                       chip->clk_div = (DIV_ROUND_UP(dws->max_freq, transfer->speed_hz) + 1) & 0xfffe;
-                       chip->speed_hz = transfer->speed_hz;
-               }
-               dws->current_freq = transfer->speed_hz;
-               spi_set_clk(dws, chip->clk_div);
-       }
-
-       transfer->effective_speed_hz = dws->max_freq / chip->clk_div;
-       dws->n_bytes = DIV_ROUND_UP(transfer->bits_per_word, BITS_PER_BYTE);
-
-       cr0 = dws->update_cr0(master, spi, transfer);
-       dw_writel(dws, DW_SPI_CTRLR0, cr0);
-
-       /* Check if current transfer is a DMA transaction */
-       if (master->can_dma && master->can_dma(master, spi, transfer))
-               dws->dma_mapped = master->cur_msg_mapped;
-
-       /* For poll mode just disable all interrupts */
-       spi_mask_intr(dws, 0xff);
-
-       /*
-        * Interrupt mode
-        * we only need set the TXEI IRQ, as TX/RX always happen syncronizely
-        */
-       if (dws->dma_mapped) {
-               ret = dws->dma_ops->dma_setup(dws, transfer);
-               if (ret < 0) {
-                       spi_enable_chip(dws, 1);
-                       return ret;
-               }
-       } else {
-               txlevel = min_t(u16, dws->fifo_len / 2, dws->len / dws->n_bytes);
-               dw_writel(dws, DW_SPI_TXFTLR, txlevel);
-
-               /* Set the interrupt mask */
-               imask |= SPI_INT_TXEI | SPI_INT_TXOI |
-                        SPI_INT_RXUI | SPI_INT_RXOI;
-               spi_umask_intr(dws, imask);
-
-               dws->transfer_handler = interrupt_transfer;
-       }
-
-       spi_enable_chip(dws, 1);
-
-       if (dws->dma_mapped)
-               return dws->dma_ops->dma_transfer(dws, transfer);
-
-       return 1;
-}
-
-static void dw_spi_handle_err(struct spi_controller *master,
-               struct spi_message *msg)
-{
-       struct dw_spi *dws = spi_controller_get_devdata(master);
-
-       if (dws->dma_mapped)
-               dws->dma_ops->dma_stop(dws);
-
-       spi_reset_chip(dws);
-}
-
-/* This may be called twice for each spi dev */
-static int dw_spi_setup(struct spi_device *spi)
-{
-       struct chip_data *chip;
-
-       /* Only alloc on first setup */
-       chip = spi_get_ctldata(spi);
-       if (!chip) {
-               chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
-               if (!chip)
-                       return -ENOMEM;
-               spi_set_ctldata(spi, chip);
-       }
-
-       chip->tmode = SPI_TMOD_TR;
-
-       return 0;
-}
-
-static void dw_spi_cleanup(struct spi_device *spi)
-{
-       struct chip_data *chip = spi_get_ctldata(spi);
-
-       kfree(chip);
-       spi_set_ctldata(spi, NULL);
-}
-
-/* Restart the controller, disable all interrupts, clean rx fifo */
-static void spi_hw_init(struct device *dev, struct dw_spi *dws)
-{
-       spi_reset_chip(dws);
-
-       /*
-        * Try to detect the FIFO depth if not set by interface driver,
-        * the depth could be from 2 to 256 from HW spec
-        */
-       if (!dws->fifo_len) {
-               u32 fifo;
-
-               for (fifo = 1; fifo < 256; fifo++) {
-                       dw_writel(dws, DW_SPI_TXFTLR, fifo);
-                       if (fifo != dw_readl(dws, DW_SPI_TXFTLR))
-                               break;
-               }
-               dw_writel(dws, DW_SPI_TXFTLR, 0);
-
-               dws->fifo_len = (fifo == 1) ? 0 : fifo;
-               dev_dbg(dev, "Detected FIFO size: %u bytes\n", dws->fifo_len);
-       }
-
-       /* enable HW fixup for explicit CS deselect for Amazon's alpine chip */
-       if (dws->cs_override)
-               dw_writel(dws, DW_SPI_CS_OVERRIDE, 0xF);
-}
-
-int dw_spi_add_host(struct device *dev, struct dw_spi *dws)
-{
-       struct spi_controller *master;
-       int ret;
-
-       if (!dws)
-               return -EINVAL;
-
-       master = spi_alloc_master(dev, 0);
-       if (!master)
-               return -ENOMEM;
-
-       dws->master = master;
-       dws->type = SSI_MOTO_SPI;
-       dws->dma_addr = (dma_addr_t)(dws->paddr + DW_SPI_DR);
-       spin_lock_init(&dws->buf_lock);
-
-       spi_controller_set_devdata(master, dws);
-
-       ret = request_irq(dws->irq, dw_spi_irq, IRQF_SHARED, dev_name(dev),
-                         master);
-       if (ret < 0) {
-               dev_err(dev, "can not get IRQ\n");
-               goto err_free_master;
-       }
-
-       master->use_gpio_descriptors = true;
-       master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP;
-       master->bits_per_word_mask =  SPI_BPW_RANGE_MASK(4, 16);
-       master->bus_num = dws->bus_num;
-       master->num_chipselect = dws->num_cs;
-       master->setup = dw_spi_setup;
-       master->cleanup = dw_spi_cleanup;
-       master->set_cs = dw_spi_set_cs;
-       master->transfer_one = dw_spi_transfer_one;
-       master->handle_err = dw_spi_handle_err;
-       master->max_speed_hz = dws->max_freq;
-       master->dev.of_node = dev->of_node;
-       master->dev.fwnode = dev->fwnode;
-       master->flags = SPI_MASTER_GPIO_SS;
-       master->auto_runtime_pm = true;
-
-       if (dws->set_cs)
-               master->set_cs = dws->set_cs;
-
-       /* Basic HW init */
-       spi_hw_init(dev, dws);
-
-       if (dws->dma_ops && dws->dma_ops->dma_init) {
-               ret = dws->dma_ops->dma_init(dev, dws);
-               if (ret) {
-                       dev_warn(dev, "DMA init failed\n");
-               } else {
-                       master->can_dma = dws->dma_ops->can_dma;
-                       master->flags |= SPI_CONTROLLER_MUST_TX;
-               }
-       }
-
-       ret = devm_spi_register_controller(dev, master);
-       if (ret) {
-               dev_err(&master->dev, "problem registering spi master\n");
-               goto err_dma_exit;
-       }
-
-       dw_spi_debugfs_init(dws);
-       return 0;
-
-err_dma_exit:
-       if (dws->dma_ops && dws->dma_ops->dma_exit)
-               dws->dma_ops->dma_exit(dws);
-       spi_enable_chip(dws, 0);
-       free_irq(dws->irq, master);
-err_free_master:
-       spi_controller_put(master);
-       return ret;
-}
-EXPORT_SYMBOL_GPL(dw_spi_add_host);
-
-void dw_spi_remove_host(struct dw_spi *dws)
-{
-       dw_spi_debugfs_remove(dws);
-
-       if (dws->dma_ops && dws->dma_ops->dma_exit)
-               dws->dma_ops->dma_exit(dws);
-
-       spi_shutdown_chip(dws);
-
-       free_irq(dws->irq, dws->master);
-}
-EXPORT_SYMBOL_GPL(dw_spi_remove_host);
-
-int dw_spi_suspend_host(struct dw_spi *dws)
-{
-       int ret;
-
-       ret = spi_controller_suspend(dws->master);
-       if (ret)
-               return ret;
-
-       spi_shutdown_chip(dws);
-       return 0;
-}
-EXPORT_SYMBOL_GPL(dw_spi_suspend_host);
-
-int dw_spi_resume_host(struct dw_spi *dws)
-{
-       spi_hw_init(&dws->master->dev, dws);
-       return spi_controller_resume(dws->master);
-}
-EXPORT_SYMBOL_GPL(dw_spi_resume_host);
-
-MODULE_AUTHOR("Feng Tang <feng.tang@intel.com>");
-MODULE_DESCRIPTION("Driver for DesignWare SPI controller core");
-MODULE_LICENSE("GPL v2");