2 * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
3 * Copyright (C) 2013, Intel Corporation
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 #include <linux/init.h>
21 #include <linux/module.h>
22 #include <linux/device.h>
23 #include <linux/ioport.h>
24 #include <linux/errno.h>
25 #include <linux/interrupt.h>
26 #include <linux/platform_device.h>
27 #include <linux/spi/pxa2xx_spi.h>
28 #include <linux/spi/spi.h>
29 #include <linux/workqueue.h>
30 #include <linux/delay.h>
31 #include <linux/gpio.h>
32 #include <linux/slab.h>
33 #include <linux/clk.h>
34 #include <linux/pm_runtime.h>
35 #include <linux/acpi.h>
39 #include <asm/delay.h>
41 #include "spi-pxa2xx.h"
43 MODULE_AUTHOR("Stephen Street");
44 MODULE_DESCRIPTION("PXA2xx SSP SPI Controller");
45 MODULE_LICENSE("GPL");
46 MODULE_ALIAS("platform:pxa2xx-spi");
50 #define TIMOUT_DFLT 1000
53 * for testing SSCR1 changes that require SSP restart, basically
54 * everything except the service and interrupt enables, the pxa270 developer
55 * manual says only SSCR1_SCFR, SSCR1_SPH, SSCR1_SPO need to be in this
56 * list, but the PXA255 dev man says all bits without really meaning the
57 * service and interrupt enables
59 #define SSCR1_CHANGE_MASK (SSCR1_TTELP | SSCR1_TTE | SSCR1_SCFR \
60 | SSCR1_ECRA | SSCR1_ECRB | SSCR1_SCLKDIR \
61 | SSCR1_SFRMDIR | SSCR1_RWOT | SSCR1_TRAIL \
62 | SSCR1_IFS | SSCR1_STRF | SSCR1_EFWR \
63 | SSCR1_RFT | SSCR1_TFT | SSCR1_MWDS \
64 | SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
66 #define LPSS_RX_THRESH_DFLT 64
67 #define LPSS_TX_LOTHRESH_DFLT 160
68 #define LPSS_TX_HITHRESH_DFLT 224
70 /* Offset from drv_data->lpss_base */
71 #define SPI_CS_CONTROL 0x18
72 #define SPI_CS_CONTROL_SW_MODE BIT(0)
73 #define SPI_CS_CONTROL_CS_HIGH BIT(1)
75 static bool is_lpss_ssp(const struct driver_data *drv_data)
77 return drv_data->ssp_type == LPSS_SSP;
81 * Read and write LPSS SSP private registers. Caller must first check that
82 * is_lpss_ssp() returns true before these can be called.
84 static u32 __lpss_ssp_read_priv(struct driver_data *drv_data, unsigned offset)
86 WARN_ON(!drv_data->lpss_base);
87 return readl(drv_data->lpss_base + offset);
90 static void __lpss_ssp_write_priv(struct driver_data *drv_data,
91 unsigned offset, u32 value)
93 WARN_ON(!drv_data->lpss_base);
94 writel(value, drv_data->lpss_base + offset);
98 * lpss_ssp_setup - perform LPSS SSP specific setup
99 * @drv_data: pointer to the driver private data
101 * Perform LPSS SSP specific setup. This function must be called first if
102 * one is going to use LPSS SSP private registers.
104 static void lpss_ssp_setup(struct driver_data *drv_data)
106 unsigned offset = 0x400;
109 if (!is_lpss_ssp(drv_data))
113 * Perform auto-detection of the LPSS SSP private registers. They
114 * can be either at 1k or 2k offset from the base address.
116 orig = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL);
118 value = orig | SPI_CS_CONTROL_SW_MODE;
119 writel(value, drv_data->ioaddr + offset + SPI_CS_CONTROL);
120 value = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL);
121 if (value != (orig | SPI_CS_CONTROL_SW_MODE)) {
126 value &= ~SPI_CS_CONTROL_SW_MODE;
127 writel(value, drv_data->ioaddr + offset + SPI_CS_CONTROL);
128 value = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL);
135 /* Now set the LPSS base */
136 drv_data->lpss_base = drv_data->ioaddr + offset;
138 /* Enable software chip select control */
139 value = SPI_CS_CONTROL_SW_MODE | SPI_CS_CONTROL_CS_HIGH;
140 __lpss_ssp_write_priv(drv_data, SPI_CS_CONTROL, value);
143 static void lpss_ssp_cs_control(struct driver_data *drv_data, bool enable)
147 if (!is_lpss_ssp(drv_data))
150 value = __lpss_ssp_read_priv(drv_data, SPI_CS_CONTROL);
152 value &= ~SPI_CS_CONTROL_CS_HIGH;
154 value |= SPI_CS_CONTROL_CS_HIGH;
155 __lpss_ssp_write_priv(drv_data, SPI_CS_CONTROL, value);
158 static void cs_assert(struct driver_data *drv_data)
160 struct chip_data *chip = drv_data->cur_chip;
162 if (drv_data->ssp_type == CE4100_SSP) {
163 write_SSSR(drv_data->cur_chip->frm, drv_data->ioaddr);
167 if (chip->cs_control) {
168 chip->cs_control(PXA2XX_CS_ASSERT);
172 if (gpio_is_valid(chip->gpio_cs)) {
173 gpio_set_value(chip->gpio_cs, chip->gpio_cs_inverted);
177 lpss_ssp_cs_control(drv_data, true);
180 static void cs_deassert(struct driver_data *drv_data)
182 struct chip_data *chip = drv_data->cur_chip;
184 if (drv_data->ssp_type == CE4100_SSP)
187 if (chip->cs_control) {
188 chip->cs_control(PXA2XX_CS_DEASSERT);
192 if (gpio_is_valid(chip->gpio_cs)) {
193 gpio_set_value(chip->gpio_cs, !chip->gpio_cs_inverted);
197 lpss_ssp_cs_control(drv_data, false);
200 int pxa2xx_spi_flush(struct driver_data *drv_data)
202 unsigned long limit = loops_per_jiffy << 1;
204 void __iomem *reg = drv_data->ioaddr;
207 while (read_SSSR(reg) & SSSR_RNE) {
210 } while ((read_SSSR(reg) & SSSR_BSY) && --limit);
211 write_SSSR_CS(drv_data, SSSR_ROR);
216 static int null_writer(struct driver_data *drv_data)
218 void __iomem *reg = drv_data->ioaddr;
219 u8 n_bytes = drv_data->n_bytes;
221 if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK)
222 || (drv_data->tx == drv_data->tx_end))
226 drv_data->tx += n_bytes;
231 static int null_reader(struct driver_data *drv_data)
233 void __iomem *reg = drv_data->ioaddr;
234 u8 n_bytes = drv_data->n_bytes;
236 while ((read_SSSR(reg) & SSSR_RNE)
237 && (drv_data->rx < drv_data->rx_end)) {
239 drv_data->rx += n_bytes;
242 return drv_data->rx == drv_data->rx_end;
245 static int u8_writer(struct driver_data *drv_data)
247 void __iomem *reg = drv_data->ioaddr;
249 if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK)
250 || (drv_data->tx == drv_data->tx_end))
253 write_SSDR(*(u8 *)(drv_data->tx), reg);
259 static int u8_reader(struct driver_data *drv_data)
261 void __iomem *reg = drv_data->ioaddr;
263 while ((read_SSSR(reg) & SSSR_RNE)
264 && (drv_data->rx < drv_data->rx_end)) {
265 *(u8 *)(drv_data->rx) = read_SSDR(reg);
269 return drv_data->rx == drv_data->rx_end;
272 static int u16_writer(struct driver_data *drv_data)
274 void __iomem *reg = drv_data->ioaddr;
276 if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK)
277 || (drv_data->tx == drv_data->tx_end))
280 write_SSDR(*(u16 *)(drv_data->tx), reg);
286 static int u16_reader(struct driver_data *drv_data)
288 void __iomem *reg = drv_data->ioaddr;
290 while ((read_SSSR(reg) & SSSR_RNE)
291 && (drv_data->rx < drv_data->rx_end)) {
292 *(u16 *)(drv_data->rx) = read_SSDR(reg);
296 return drv_data->rx == drv_data->rx_end;
299 static int u32_writer(struct driver_data *drv_data)
301 void __iomem *reg = drv_data->ioaddr;
303 if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK)
304 || (drv_data->tx == drv_data->tx_end))
307 write_SSDR(*(u32 *)(drv_data->tx), reg);
313 static int u32_reader(struct driver_data *drv_data)
315 void __iomem *reg = drv_data->ioaddr;
317 while ((read_SSSR(reg) & SSSR_RNE)
318 && (drv_data->rx < drv_data->rx_end)) {
319 *(u32 *)(drv_data->rx) = read_SSDR(reg);
323 return drv_data->rx == drv_data->rx_end;
326 void *pxa2xx_spi_next_transfer(struct driver_data *drv_data)
328 struct spi_message *msg = drv_data->cur_msg;
329 struct spi_transfer *trans = drv_data->cur_transfer;
331 /* Move to next transfer */
332 if (trans->transfer_list.next != &msg->transfers) {
333 drv_data->cur_transfer =
334 list_entry(trans->transfer_list.next,
337 return RUNNING_STATE;
342 /* caller already set message->status; dma and pio irqs are blocked */
343 static void giveback(struct driver_data *drv_data)
345 struct spi_transfer* last_transfer;
346 struct spi_message *msg;
348 msg = drv_data->cur_msg;
349 drv_data->cur_msg = NULL;
350 drv_data->cur_transfer = NULL;
352 last_transfer = list_entry(msg->transfers.prev,
356 /* Delay if requested before any change in chip select */
357 if (last_transfer->delay_usecs)
358 udelay(last_transfer->delay_usecs);
360 /* Drop chip select UNLESS cs_change is true or we are returning
361 * a message with an error, or next message is for another chip
363 if (!last_transfer->cs_change)
364 cs_deassert(drv_data);
366 struct spi_message *next_msg;
368 /* Holding of cs was hinted, but we need to make sure
369 * the next message is for the same chip. Don't waste
370 * time with the following tests unless this was hinted.
372 * We cannot postpone this until pump_messages, because
373 * after calling msg->complete (below) the driver that
374 * sent the current message could be unloaded, which
375 * could invalidate the cs_control() callback...
378 /* get a pointer to the next message, if any */
379 next_msg = spi_get_next_queued_message(drv_data->master);
381 /* see if the next and current messages point
384 if (next_msg && next_msg->spi != msg->spi)
386 if (!next_msg || msg->state == ERROR_STATE)
387 cs_deassert(drv_data);
390 spi_finalize_current_message(drv_data->master);
391 drv_data->cur_chip = NULL;
394 static void reset_sccr1(struct driver_data *drv_data)
396 void __iomem *reg = drv_data->ioaddr;
397 struct chip_data *chip = drv_data->cur_chip;
400 sccr1_reg = read_SSCR1(reg) & ~drv_data->int_cr1;
401 sccr1_reg &= ~SSCR1_RFT;
402 sccr1_reg |= chip->threshold;
403 write_SSCR1(sccr1_reg, reg);
406 static void int_error_stop(struct driver_data *drv_data, const char* msg)
408 void __iomem *reg = drv_data->ioaddr;
410 /* Stop and reset SSP */
411 write_SSSR_CS(drv_data, drv_data->clear_sr);
412 reset_sccr1(drv_data);
413 if (!pxa25x_ssp_comp(drv_data))
415 pxa2xx_spi_flush(drv_data);
416 write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg);
418 dev_err(&drv_data->pdev->dev, "%s\n", msg);
420 drv_data->cur_msg->state = ERROR_STATE;
421 tasklet_schedule(&drv_data->pump_transfers);
424 static void int_transfer_complete(struct driver_data *drv_data)
426 void __iomem *reg = drv_data->ioaddr;
429 write_SSSR_CS(drv_data, drv_data->clear_sr);
430 reset_sccr1(drv_data);
431 if (!pxa25x_ssp_comp(drv_data))
434 /* Update total byte transferred return count actual bytes read */
435 drv_data->cur_msg->actual_length += drv_data->len -
436 (drv_data->rx_end - drv_data->rx);
438 /* Transfer delays and chip select release are
439 * handled in pump_transfers or giveback
442 /* Move to next transfer */
443 drv_data->cur_msg->state = pxa2xx_spi_next_transfer(drv_data);
445 /* Schedule transfer tasklet */
446 tasklet_schedule(&drv_data->pump_transfers);
449 static irqreturn_t interrupt_transfer(struct driver_data *drv_data)
451 void __iomem *reg = drv_data->ioaddr;
453 u32 irq_mask = (read_SSCR1(reg) & SSCR1_TIE) ?
454 drv_data->mask_sr : drv_data->mask_sr & ~SSSR_TFS;
456 u32 irq_status = read_SSSR(reg) & irq_mask;
458 if (irq_status & SSSR_ROR) {
459 int_error_stop(drv_data, "interrupt_transfer: fifo overrun");
463 if (irq_status & SSSR_TINT) {
464 write_SSSR(SSSR_TINT, reg);
465 if (drv_data->read(drv_data)) {
466 int_transfer_complete(drv_data);
471 /* Drain rx fifo, Fill tx fifo and prevent overruns */
473 if (drv_data->read(drv_data)) {
474 int_transfer_complete(drv_data);
477 } while (drv_data->write(drv_data));
479 if (drv_data->read(drv_data)) {
480 int_transfer_complete(drv_data);
484 if (drv_data->tx == drv_data->tx_end) {
488 sccr1_reg = read_SSCR1(reg);
489 sccr1_reg &= ~SSCR1_TIE;
492 * PXA25x_SSP has no timeout, set up rx threshould for the
493 * remaining RX bytes.
495 if (pxa25x_ssp_comp(drv_data)) {
497 sccr1_reg &= ~SSCR1_RFT;
499 bytes_left = drv_data->rx_end - drv_data->rx;
500 switch (drv_data->n_bytes) {
507 if (bytes_left > RX_THRESH_DFLT)
508 bytes_left = RX_THRESH_DFLT;
510 sccr1_reg |= SSCR1_RxTresh(bytes_left);
512 write_SSCR1(sccr1_reg, reg);
515 /* We did something */
519 static irqreturn_t ssp_int(int irq, void *dev_id)
521 struct driver_data *drv_data = dev_id;
522 void __iomem *reg = drv_data->ioaddr;
524 u32 mask = drv_data->mask_sr;
528 * The IRQ might be shared with other peripherals so we must first
529 * check that are we RPM suspended or not. If we are we assume that
530 * the IRQ was not for us (we shouldn't be RPM suspended when the
531 * interrupt is enabled).
533 if (pm_runtime_suspended(&drv_data->pdev->dev))
536 sccr1_reg = read_SSCR1(reg);
537 status = read_SSSR(reg);
539 /* Ignore possible writes if we don't need to write */
540 if (!(sccr1_reg & SSCR1_TIE))
543 if (!(status & mask))
546 if (!drv_data->cur_msg) {
548 write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg);
549 write_SSCR1(read_SSCR1(reg) & ~drv_data->int_cr1, reg);
550 if (!pxa25x_ssp_comp(drv_data))
552 write_SSSR_CS(drv_data, drv_data->clear_sr);
554 dev_err(&drv_data->pdev->dev, "bad message state "
555 "in interrupt handler\n");
561 return drv_data->transfer_handler(drv_data);
564 static unsigned int ssp_get_clk_div(struct driver_data *drv_data, int rate)
566 unsigned long ssp_clk = drv_data->max_clk_rate;
567 const struct ssp_device *ssp = drv_data->ssp;
569 rate = min_t(int, ssp_clk, rate);
571 if (ssp->type == PXA25x_SSP || ssp->type == CE4100_SSP)
572 return ((ssp_clk / (2 * rate) - 1) & 0xff) << 8;
574 return ((ssp_clk / rate - 1) & 0xfff) << 8;
577 static void pump_transfers(unsigned long data)
579 struct driver_data *drv_data = (struct driver_data *)data;
580 struct spi_message *message = NULL;
581 struct spi_transfer *transfer = NULL;
582 struct spi_transfer *previous = NULL;
583 struct chip_data *chip = NULL;
584 void __iomem *reg = drv_data->ioaddr;
590 u32 dma_thresh = drv_data->cur_chip->dma_threshold;
591 u32 dma_burst = drv_data->cur_chip->dma_burst_size;
593 /* Get current state information */
594 message = drv_data->cur_msg;
595 transfer = drv_data->cur_transfer;
596 chip = drv_data->cur_chip;
598 /* Handle for abort */
599 if (message->state == ERROR_STATE) {
600 message->status = -EIO;
605 /* Handle end of message */
606 if (message->state == DONE_STATE) {
612 /* Delay if requested at end of transfer before CS change */
613 if (message->state == RUNNING_STATE) {
614 previous = list_entry(transfer->transfer_list.prev,
617 if (previous->delay_usecs)
618 udelay(previous->delay_usecs);
620 /* Drop chip select only if cs_change is requested */
621 if (previous->cs_change)
622 cs_deassert(drv_data);
625 /* Check if we can DMA this transfer */
626 if (!pxa2xx_spi_dma_is_possible(transfer->len) && chip->enable_dma) {
628 /* reject already-mapped transfers; PIO won't always work */
629 if (message->is_dma_mapped
630 || transfer->rx_dma || transfer->tx_dma) {
631 dev_err(&drv_data->pdev->dev,
632 "pump_transfers: mapped transfer length "
633 "of %u is greater than %d\n",
634 transfer->len, MAX_DMA_LEN);
635 message->status = -EINVAL;
640 /* warn ... we force this to PIO mode */
641 if (printk_ratelimit())
642 dev_warn(&message->spi->dev, "pump_transfers: "
643 "DMA disabled for transfer length %ld "
645 (long)drv_data->len, MAX_DMA_LEN);
648 /* Setup the transfer state based on the type of transfer */
649 if (pxa2xx_spi_flush(drv_data) == 0) {
650 dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n");
651 message->status = -EIO;
655 drv_data->n_bytes = chip->n_bytes;
656 drv_data->tx = (void *)transfer->tx_buf;
657 drv_data->tx_end = drv_data->tx + transfer->len;
658 drv_data->rx = transfer->rx_buf;
659 drv_data->rx_end = drv_data->rx + transfer->len;
660 drv_data->rx_dma = transfer->rx_dma;
661 drv_data->tx_dma = transfer->tx_dma;
662 drv_data->len = transfer->len;
663 drv_data->write = drv_data->tx ? chip->write : null_writer;
664 drv_data->read = drv_data->rx ? chip->read : null_reader;
666 /* Change speed and bit per word on a per transfer */
668 if (transfer->speed_hz || transfer->bits_per_word) {
670 bits = chip->bits_per_word;
671 speed = chip->speed_hz;
673 if (transfer->speed_hz)
674 speed = transfer->speed_hz;
676 if (transfer->bits_per_word)
677 bits = transfer->bits_per_word;
679 clk_div = ssp_get_clk_div(drv_data, speed);
682 drv_data->n_bytes = 1;
683 drv_data->read = drv_data->read != null_reader ?
684 u8_reader : null_reader;
685 drv_data->write = drv_data->write != null_writer ?
686 u8_writer : null_writer;
687 } else if (bits <= 16) {
688 drv_data->n_bytes = 2;
689 drv_data->read = drv_data->read != null_reader ?
690 u16_reader : null_reader;
691 drv_data->write = drv_data->write != null_writer ?
692 u16_writer : null_writer;
693 } else if (bits <= 32) {
694 drv_data->n_bytes = 4;
695 drv_data->read = drv_data->read != null_reader ?
696 u32_reader : null_reader;
697 drv_data->write = drv_data->write != null_writer ?
698 u32_writer : null_writer;
700 /* if bits/word is changed in dma mode, then must check the
701 * thresholds and burst also */
702 if (chip->enable_dma) {
703 if (pxa2xx_spi_set_dma_burst_and_threshold(chip,
707 if (printk_ratelimit())
708 dev_warn(&message->spi->dev,
710 "DMA burst size reduced to "
711 "match bits_per_word\n");
716 | SSCR0_DataSize(bits > 16 ? bits - 16 : bits)
718 | (bits > 16 ? SSCR0_EDSS : 0);
721 message->state = RUNNING_STATE;
723 drv_data->dma_mapped = 0;
724 if (pxa2xx_spi_dma_is_possible(drv_data->len))
725 drv_data->dma_mapped = pxa2xx_spi_map_dma_buffers(drv_data);
726 if (drv_data->dma_mapped) {
728 /* Ensure we have the correct interrupt handler */
729 drv_data->transfer_handler = pxa2xx_spi_dma_transfer;
731 pxa2xx_spi_dma_prepare(drv_data, dma_burst);
733 /* Clear status and start DMA engine */
734 cr1 = chip->cr1 | dma_thresh | drv_data->dma_cr1;
735 write_SSSR(drv_data->clear_sr, reg);
737 pxa2xx_spi_dma_start(drv_data);
739 /* Ensure we have the correct interrupt handler */
740 drv_data->transfer_handler = interrupt_transfer;
743 cr1 = chip->cr1 | chip->threshold | drv_data->int_cr1;
744 write_SSSR_CS(drv_data, drv_data->clear_sr);
747 if (is_lpss_ssp(drv_data)) {
748 if ((read_SSIRF(reg) & 0xff) != chip->lpss_rx_threshold)
749 write_SSIRF(chip->lpss_rx_threshold, reg);
750 if ((read_SSITF(reg) & 0xffff) != chip->lpss_tx_threshold)
751 write_SSITF(chip->lpss_tx_threshold, reg);
754 /* see if we need to reload the config registers */
755 if ((read_SSCR0(reg) != cr0)
756 || (read_SSCR1(reg) & SSCR1_CHANGE_MASK) !=
757 (cr1 & SSCR1_CHANGE_MASK)) {
759 /* stop the SSP, and update the other bits */
760 write_SSCR0(cr0 & ~SSCR0_SSE, reg);
761 if (!pxa25x_ssp_comp(drv_data))
762 write_SSTO(chip->timeout, reg);
763 /* first set CR1 without interrupt and service enables */
764 write_SSCR1(cr1 & SSCR1_CHANGE_MASK, reg);
765 /* restart the SSP */
766 write_SSCR0(cr0, reg);
769 if (!pxa25x_ssp_comp(drv_data))
770 write_SSTO(chip->timeout, reg);
775 /* after chip select, release the data by enabling service
776 * requests and interrupts, without changing any mode bits */
777 write_SSCR1(cr1, reg);
780 static int pxa2xx_spi_transfer_one_message(struct spi_master *master,
781 struct spi_message *msg)
783 struct driver_data *drv_data = spi_master_get_devdata(master);
785 drv_data->cur_msg = msg;
786 /* Initial message state*/
787 drv_data->cur_msg->state = START_STATE;
788 drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
792 /* prepare to setup the SSP, in pump_transfers, using the per
793 * chip configuration */
794 drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
796 /* Mark as busy and launch transfers */
797 tasklet_schedule(&drv_data->pump_transfers);
801 static int pxa2xx_spi_prepare_transfer(struct spi_master *master)
803 struct driver_data *drv_data = spi_master_get_devdata(master);
805 pm_runtime_get_sync(&drv_data->pdev->dev);
809 static int pxa2xx_spi_unprepare_transfer(struct spi_master *master)
811 struct driver_data *drv_data = spi_master_get_devdata(master);
813 /* Disable the SSP now */
814 write_SSCR0(read_SSCR0(drv_data->ioaddr) & ~SSCR0_SSE,
817 pm_runtime_mark_last_busy(&drv_data->pdev->dev);
818 pm_runtime_put_autosuspend(&drv_data->pdev->dev);
822 static int setup_cs(struct spi_device *spi, struct chip_data *chip,
823 struct pxa2xx_spi_chip *chip_info)
827 if (chip == NULL || chip_info == NULL)
830 /* NOTE: setup() can be called multiple times, possibly with
831 * different chip_info, release previously requested GPIO
833 if (gpio_is_valid(chip->gpio_cs))
834 gpio_free(chip->gpio_cs);
836 /* If (*cs_control) is provided, ignore GPIO chip select */
837 if (chip_info->cs_control) {
838 chip->cs_control = chip_info->cs_control;
842 if (gpio_is_valid(chip_info->gpio_cs)) {
843 err = gpio_request(chip_info->gpio_cs, "SPI_CS");
845 dev_err(&spi->dev, "failed to request chip select "
846 "GPIO%d\n", chip_info->gpio_cs);
850 chip->gpio_cs = chip_info->gpio_cs;
851 chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH;
853 err = gpio_direction_output(chip->gpio_cs,
854 !chip->gpio_cs_inverted);
860 static int setup(struct spi_device *spi)
862 struct pxa2xx_spi_chip *chip_info = NULL;
863 struct chip_data *chip;
864 struct driver_data *drv_data = spi_master_get_devdata(spi->master);
865 unsigned int clk_div;
866 uint tx_thres, tx_hi_thres, rx_thres;
868 if (is_lpss_ssp(drv_data)) {
869 tx_thres = LPSS_TX_LOTHRESH_DFLT;
870 tx_hi_thres = LPSS_TX_HITHRESH_DFLT;
871 rx_thres = LPSS_RX_THRESH_DFLT;
873 tx_thres = TX_THRESH_DFLT;
875 rx_thres = RX_THRESH_DFLT;
878 if (!pxa25x_ssp_comp(drv_data)
879 && (spi->bits_per_word < 4 || spi->bits_per_word > 32)) {
880 dev_err(&spi->dev, "failed setup: ssp_type=%d, bits/wrd=%d "
881 "b/w not 4-32 for type non-PXA25x_SSP\n",
882 drv_data->ssp_type, spi->bits_per_word);
884 } else if (pxa25x_ssp_comp(drv_data)
885 && (spi->bits_per_word < 4
886 || spi->bits_per_word > 16)) {
887 dev_err(&spi->dev, "failed setup: ssp_type=%d, bits/wrd=%d "
888 "b/w not 4-16 for type PXA25x_SSP\n",
889 drv_data->ssp_type, spi->bits_per_word);
893 /* Only alloc on first setup */
894 chip = spi_get_ctldata(spi);
896 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
899 "failed setup: can't allocate chip data\n");
903 if (drv_data->ssp_type == CE4100_SSP) {
904 if (spi->chip_select > 4) {
905 dev_err(&spi->dev, "failed setup: "
906 "cs number must not be > 4.\n");
911 chip->frm = spi->chip_select;
914 chip->enable_dma = 0;
915 chip->timeout = TIMOUT_DFLT;
918 /* protocol drivers may change the chip settings, so...
919 * if chip_info exists, use it */
920 chip_info = spi->controller_data;
922 /* chip_info isn't always needed */
925 if (chip_info->timeout)
926 chip->timeout = chip_info->timeout;
927 if (chip_info->tx_threshold)
928 tx_thres = chip_info->tx_threshold;
929 if (chip_info->tx_hi_threshold)
930 tx_hi_thres = chip_info->tx_hi_threshold;
931 if (chip_info->rx_threshold)
932 rx_thres = chip_info->rx_threshold;
933 chip->enable_dma = drv_data->master_info->enable_dma;
934 chip->dma_threshold = 0;
935 if (chip_info->enable_loopback)
936 chip->cr1 = SSCR1_LBM;
937 } else if (ACPI_HANDLE(&spi->dev)) {
939 * Slave devices enumerated from ACPI namespace don't
940 * usually have chip_info but we still might want to use
943 chip->enable_dma = drv_data->master_info->enable_dma;
946 chip->threshold = (SSCR1_RxTresh(rx_thres) & SSCR1_RFT) |
947 (SSCR1_TxTresh(tx_thres) & SSCR1_TFT);
949 chip->lpss_rx_threshold = SSIRF_RxThresh(rx_thres);
950 chip->lpss_tx_threshold = SSITF_TxLoThresh(tx_thres)
951 | SSITF_TxHiThresh(tx_hi_thres);
953 /* set dma burst and threshold outside of chip_info path so that if
954 * chip_info goes away after setting chip->enable_dma, the
955 * burst and threshold can still respond to changes in bits_per_word */
956 if (chip->enable_dma) {
957 /* set up legal burst and threshold for dma */
958 if (pxa2xx_spi_set_dma_burst_and_threshold(chip, spi,
960 &chip->dma_burst_size,
961 &chip->dma_threshold)) {
962 dev_warn(&spi->dev, "in setup: DMA burst size reduced "
963 "to match bits_per_word\n");
967 clk_div = ssp_get_clk_div(drv_data, spi->max_speed_hz);
968 chip->speed_hz = spi->max_speed_hz;
972 | SSCR0_DataSize(spi->bits_per_word > 16 ?
973 spi->bits_per_word - 16 : spi->bits_per_word)
975 | (spi->bits_per_word > 16 ? SSCR0_EDSS : 0);
976 chip->cr1 &= ~(SSCR1_SPO | SSCR1_SPH);
977 chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) ? SSCR1_SPH : 0)
978 | (((spi->mode & SPI_CPOL) != 0) ? SSCR1_SPO : 0);
980 if (spi->mode & SPI_LOOP)
981 chip->cr1 |= SSCR1_LBM;
983 /* NOTE: PXA25x_SSP _could_ use external clocking ... */
984 if (!pxa25x_ssp_comp(drv_data))
985 dev_dbg(&spi->dev, "%ld Hz actual, %s\n",
986 drv_data->max_clk_rate
987 / (1 + ((chip->cr0 & SSCR0_SCR(0xfff)) >> 8)),
988 chip->enable_dma ? "DMA" : "PIO");
990 dev_dbg(&spi->dev, "%ld Hz actual, %s\n",
991 drv_data->max_clk_rate / 2
992 / (1 + ((chip->cr0 & SSCR0_SCR(0x0ff)) >> 8)),
993 chip->enable_dma ? "DMA" : "PIO");
995 if (spi->bits_per_word <= 8) {
997 chip->read = u8_reader;
998 chip->write = u8_writer;
999 } else if (spi->bits_per_word <= 16) {
1001 chip->read = u16_reader;
1002 chip->write = u16_writer;
1003 } else if (spi->bits_per_word <= 32) {
1004 chip->cr0 |= SSCR0_EDSS;
1006 chip->read = u32_reader;
1007 chip->write = u32_writer;
1009 dev_err(&spi->dev, "invalid wordsize\n");
1012 chip->bits_per_word = spi->bits_per_word;
1014 spi_set_ctldata(spi, chip);
1016 if (drv_data->ssp_type == CE4100_SSP)
1019 return setup_cs(spi, chip, chip_info);
1022 static void cleanup(struct spi_device *spi)
1024 struct chip_data *chip = spi_get_ctldata(spi);
1025 struct driver_data *drv_data = spi_master_get_devdata(spi->master);
1030 if (drv_data->ssp_type != CE4100_SSP && gpio_is_valid(chip->gpio_cs))
1031 gpio_free(chip->gpio_cs);
1037 static int pxa2xx_spi_acpi_add_dma(struct acpi_resource *res, void *data)
1039 struct pxa2xx_spi_master *pdata = data;
1041 if (res->type == ACPI_RESOURCE_TYPE_FIXED_DMA) {
1042 const struct acpi_resource_fixed_dma *dma;
1044 dma = &res->data.fixed_dma;
1045 if (pdata->tx_slave_id < 0) {
1046 pdata->tx_slave_id = dma->request_lines;
1047 pdata->tx_chan_id = dma->channels;
1048 } else if (pdata->rx_slave_id < 0) {
1049 pdata->rx_slave_id = dma->request_lines;
1050 pdata->rx_chan_id = dma->channels;
1054 /* Tell the ACPI core to skip this resource */
1058 static struct pxa2xx_spi_master *
1059 pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
1061 struct pxa2xx_spi_master *pdata;
1062 struct list_head resource_list;
1063 struct acpi_device *adev;
1064 struct ssp_device *ssp;
1065 struct resource *res;
1068 if (!ACPI_HANDLE(&pdev->dev) ||
1069 acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev))
1072 pdata = devm_kzalloc(&pdev->dev, sizeof(*ssp), GFP_KERNEL);
1075 "failed to allocate memory for platform data\n");
1079 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1085 ssp->phys_base = res->start;
1086 ssp->mmio_base = devm_request_and_ioremap(&pdev->dev, res);
1087 if (!ssp->mmio_base) {
1088 dev_err(&pdev->dev, "failed to ioremap mmio_base\n");
1092 ssp->clk = devm_clk_get(&pdev->dev, NULL);
1093 ssp->irq = platform_get_irq(pdev, 0);
1094 ssp->type = LPSS_SSP;
1098 if (adev->pnp.unique_id && !kstrtoint(adev->pnp.unique_id, 0, &devid))
1099 ssp->port_id = devid;
1101 pdata->num_chipselect = 1;
1102 pdata->rx_slave_id = -1;
1103 pdata->tx_slave_id = -1;
1105 INIT_LIST_HEAD(&resource_list);
1106 acpi_dev_get_resources(adev, &resource_list, pxa2xx_spi_acpi_add_dma,
1108 acpi_dev_free_resource_list(&resource_list);
1110 pdata->enable_dma = pdata->rx_slave_id >= 0 && pdata->tx_slave_id >= 0;
1115 static struct acpi_device_id pxa2xx_spi_acpi_match[] = {
1120 MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match);
1122 static inline struct pxa2xx_spi_master *
1123 pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
1129 static int pxa2xx_spi_probe(struct platform_device *pdev)
1131 struct device *dev = &pdev->dev;
1132 struct pxa2xx_spi_master *platform_info;
1133 struct spi_master *master;
1134 struct driver_data *drv_data;
1135 struct ssp_device *ssp;
1138 platform_info = dev_get_platdata(dev);
1139 if (!platform_info) {
1140 platform_info = pxa2xx_spi_acpi_get_pdata(pdev);
1141 if (!platform_info) {
1142 dev_err(&pdev->dev, "missing platform data\n");
1147 ssp = pxa_ssp_request(pdev->id, pdev->name);
1149 ssp = &platform_info->ssp;
1151 if (!ssp->mmio_base) {
1152 dev_err(&pdev->dev, "failed to get ssp\n");
1156 /* Allocate master with space for drv_data and null dma buffer */
1157 master = spi_alloc_master(dev, sizeof(struct driver_data) + 16);
1159 dev_err(&pdev->dev, "cannot alloc spi_master\n");
1163 drv_data = spi_master_get_devdata(master);
1164 drv_data->master = master;
1165 drv_data->master_info = platform_info;
1166 drv_data->pdev = pdev;
1167 drv_data->ssp = ssp;
1169 master->dev.parent = &pdev->dev;
1170 master->dev.of_node = pdev->dev.of_node;
1171 ACPI_HANDLE_SET(&master->dev, ACPI_HANDLE(&pdev->dev));
1172 /* the spi->mode bits understood by this driver: */
1173 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
1175 master->bus_num = ssp->port_id;
1176 master->num_chipselect = platform_info->num_chipselect;
1177 master->dma_alignment = DMA_ALIGNMENT;
1178 master->cleanup = cleanup;
1179 master->setup = setup;
1180 master->transfer_one_message = pxa2xx_spi_transfer_one_message;
1181 master->prepare_transfer_hardware = pxa2xx_spi_prepare_transfer;
1182 master->unprepare_transfer_hardware = pxa2xx_spi_unprepare_transfer;
1184 drv_data->ssp_type = ssp->type;
1185 drv_data->null_dma_buf = (u32 *)PTR_ALIGN(&drv_data[1], DMA_ALIGNMENT);
1187 drv_data->ioaddr = ssp->mmio_base;
1188 drv_data->ssdr_physical = ssp->phys_base + SSDR;
1189 if (pxa25x_ssp_comp(drv_data)) {
1190 drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE;
1191 drv_data->dma_cr1 = 0;
1192 drv_data->clear_sr = SSSR_ROR;
1193 drv_data->mask_sr = SSSR_RFS | SSSR_TFS | SSSR_ROR;
1195 drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE | SSCR1_TINTE;
1196 drv_data->dma_cr1 = DEFAULT_DMA_CR1;
1197 drv_data->clear_sr = SSSR_ROR | SSSR_TINT;
1198 drv_data->mask_sr = SSSR_TINT | SSSR_RFS | SSSR_TFS | SSSR_ROR;
1201 status = request_irq(ssp->irq, ssp_int, IRQF_SHARED, dev_name(dev),
1204 dev_err(&pdev->dev, "cannot get IRQ %d\n", ssp->irq);
1205 goto out_error_master_alloc;
1208 /* Setup DMA if requested */
1209 drv_data->tx_channel = -1;
1210 drv_data->rx_channel = -1;
1211 if (platform_info->enable_dma) {
1212 status = pxa2xx_spi_dma_setup(drv_data);
1214 dev_warn(dev, "failed to setup DMA, using PIO\n");
1215 platform_info->enable_dma = false;
1219 /* Enable SOC clock */
1220 clk_prepare_enable(ssp->clk);
1222 drv_data->max_clk_rate = clk_get_rate(ssp->clk);
1224 /* Load default SSP configuration */
1225 write_SSCR0(0, drv_data->ioaddr);
1226 write_SSCR1(SSCR1_RxTresh(RX_THRESH_DFLT) |
1227 SSCR1_TxTresh(TX_THRESH_DFLT),
1229 write_SSCR0(SSCR0_SCR(2)
1231 | SSCR0_DataSize(8),
1233 if (!pxa25x_ssp_comp(drv_data))
1234 write_SSTO(0, drv_data->ioaddr);
1235 write_SSPSP(0, drv_data->ioaddr);
1237 lpss_ssp_setup(drv_data);
1239 tasklet_init(&drv_data->pump_transfers, pump_transfers,
1240 (unsigned long)drv_data);
1242 /* Register with the SPI framework */
1243 platform_set_drvdata(pdev, drv_data);
1244 status = spi_register_master(master);
1246 dev_err(&pdev->dev, "problem registering spi master\n");
1247 goto out_error_clock_enabled;
1250 pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
1251 pm_runtime_use_autosuspend(&pdev->dev);
1252 pm_runtime_set_active(&pdev->dev);
1253 pm_runtime_enable(&pdev->dev);
1257 out_error_clock_enabled:
1258 clk_disable_unprepare(ssp->clk);
1259 pxa2xx_spi_dma_release(drv_data);
1260 free_irq(ssp->irq, drv_data);
1262 out_error_master_alloc:
1263 spi_master_put(master);
1268 static int pxa2xx_spi_remove(struct platform_device *pdev)
1270 struct driver_data *drv_data = platform_get_drvdata(pdev);
1271 struct ssp_device *ssp;
1275 ssp = drv_data->ssp;
1277 pm_runtime_get_sync(&pdev->dev);
1279 /* Disable the SSP at the peripheral and SOC level */
1280 write_SSCR0(0, drv_data->ioaddr);
1281 clk_disable_unprepare(ssp->clk);
1284 if (drv_data->master_info->enable_dma)
1285 pxa2xx_spi_dma_release(drv_data);
1287 pm_runtime_put_noidle(&pdev->dev);
1288 pm_runtime_disable(&pdev->dev);
1291 free_irq(ssp->irq, drv_data);
1296 /* Disconnect from the SPI framework */
1297 spi_unregister_master(drv_data->master);
1299 /* Prevent double remove */
1300 platform_set_drvdata(pdev, NULL);
1305 static void pxa2xx_spi_shutdown(struct platform_device *pdev)
1309 if ((status = pxa2xx_spi_remove(pdev)) != 0)
1310 dev_err(&pdev->dev, "shutdown failed with %d\n", status);
1314 static int pxa2xx_spi_suspend(struct device *dev)
1316 struct driver_data *drv_data = dev_get_drvdata(dev);
1317 struct ssp_device *ssp = drv_data->ssp;
1320 status = spi_master_suspend(drv_data->master);
1323 write_SSCR0(0, drv_data->ioaddr);
1324 clk_disable_unprepare(ssp->clk);
1329 static int pxa2xx_spi_resume(struct device *dev)
1331 struct driver_data *drv_data = dev_get_drvdata(dev);
1332 struct ssp_device *ssp = drv_data->ssp;
1335 pxa2xx_spi_dma_resume(drv_data);
1337 /* Enable the SSP clock */
1338 clk_prepare_enable(ssp->clk);
1340 /* Start the queue running */
1341 status = spi_master_resume(drv_data->master);
1343 dev_err(dev, "problem starting queue (%d)\n", status);
1351 #ifdef CONFIG_PM_RUNTIME
1352 static int pxa2xx_spi_runtime_suspend(struct device *dev)
1354 struct driver_data *drv_data = dev_get_drvdata(dev);
1356 clk_disable_unprepare(drv_data->ssp->clk);
1360 static int pxa2xx_spi_runtime_resume(struct device *dev)
1362 struct driver_data *drv_data = dev_get_drvdata(dev);
1364 clk_prepare_enable(drv_data->ssp->clk);
1369 static const struct dev_pm_ops pxa2xx_spi_pm_ops = {
1370 SET_SYSTEM_SLEEP_PM_OPS(pxa2xx_spi_suspend, pxa2xx_spi_resume)
1371 SET_RUNTIME_PM_OPS(pxa2xx_spi_runtime_suspend,
1372 pxa2xx_spi_runtime_resume, NULL)
1375 static struct platform_driver driver = {
1377 .name = "pxa2xx-spi",
1378 .owner = THIS_MODULE,
1379 .pm = &pxa2xx_spi_pm_ops,
1380 .acpi_match_table = ACPI_PTR(pxa2xx_spi_acpi_match),
1382 .probe = pxa2xx_spi_probe,
1383 .remove = pxa2xx_spi_remove,
1384 .shutdown = pxa2xx_spi_shutdown,
1387 static int __init pxa2xx_spi_init(void)
1389 return platform_driver_register(&driver);
1391 subsys_initcall(pxa2xx_spi_init);
1393 static void __exit pxa2xx_spi_exit(void)
1395 platform_driver_unregister(&driver);
1397 module_exit(pxa2xx_spi_exit);