linux/drivers/spi/spi-fsl-lpspi.c
Uwe Kleine-König edd49c8987
spi: fsl-lpspi: Convert to platform remove callback returning void
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230303172041.2103336-27-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-03-06 12:31:25 +00:00

992 lines
24 KiB
C

// SPDX-License-Identifier: GPL-2.0+
//
// Freescale i.MX7ULP LPSPI driver
//
// Copyright 2016 Freescale Semiconductor, Inc.
// Copyright 2018 NXP Semiconductors
#include <linux/clk.h>
#include <linux/completion.h>
#include <linux/delay.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include <linux/dma/imx-dma.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>
#include <linux/spi/spi_bitbang.h>
#include <linux/types.h>
#define DRIVER_NAME "fsl_lpspi"
#define FSL_LPSPI_RPM_TIMEOUT 50 /* 50ms */
/* The maximum bytes that edma can transfer once.*/
#define FSL_LPSPI_MAX_EDMA_BYTES ((1 << 15) - 1)
/* i.MX7ULP LPSPI registers */
#define IMX7ULP_VERID 0x0
#define IMX7ULP_PARAM 0x4
#define IMX7ULP_CR 0x10
#define IMX7ULP_SR 0x14
#define IMX7ULP_IER 0x18
#define IMX7ULP_DER 0x1c
#define IMX7ULP_CFGR0 0x20
#define IMX7ULP_CFGR1 0x24
#define IMX7ULP_DMR0 0x30
#define IMX7ULP_DMR1 0x34
#define IMX7ULP_CCR 0x40
#define IMX7ULP_FCR 0x58
#define IMX7ULP_FSR 0x5c
#define IMX7ULP_TCR 0x60
#define IMX7ULP_TDR 0x64
#define IMX7ULP_RSR 0x70
#define IMX7ULP_RDR 0x74
/* General control register field define */
#define CR_RRF BIT(9)
#define CR_RTF BIT(8)
#define CR_RST BIT(1)
#define CR_MEN BIT(0)
#define SR_MBF BIT(24)
#define SR_TCF BIT(10)
#define SR_FCF BIT(9)
#define SR_RDF BIT(1)
#define SR_TDF BIT(0)
#define IER_TCIE BIT(10)
#define IER_FCIE BIT(9)
#define IER_RDIE BIT(1)
#define IER_TDIE BIT(0)
#define DER_RDDE BIT(1)
#define DER_TDDE BIT(0)
#define CFGR1_PCSCFG BIT(27)
#define CFGR1_PINCFG (BIT(24)|BIT(25))
#define CFGR1_PCSPOL BIT(8)
#define CFGR1_NOSTALL BIT(3)
#define CFGR1_MASTER BIT(0)
#define FSR_TXCOUNT (0xFF)
#define RSR_RXEMPTY BIT(1)
#define TCR_CPOL BIT(31)
#define TCR_CPHA BIT(30)
#define TCR_CONT BIT(21)
#define TCR_CONTC BIT(20)
#define TCR_RXMSK BIT(19)
#define TCR_TXMSK BIT(18)
struct lpspi_config {
u8 bpw;
u8 chip_select;
u8 prescale;
u16 mode;
u32 speed_hz;
};
struct fsl_lpspi_data {
struct device *dev;
void __iomem *base;
unsigned long base_phys;
struct clk *clk_ipg;
struct clk *clk_per;
bool is_slave;
u32 num_cs;
bool is_only_cs1;
bool is_first_byte;
void *rx_buf;
const void *tx_buf;
void (*tx)(struct fsl_lpspi_data *);
void (*rx)(struct fsl_lpspi_data *);
u32 remain;
u8 watermark;
u8 txfifosize;
u8 rxfifosize;
struct lpspi_config config;
struct completion xfer_done;
bool slave_aborted;
/* DMA */
bool usedma;
struct completion dma_rx_completion;
struct completion dma_tx_completion;
};
static const struct of_device_id fsl_lpspi_dt_ids[] = {
{ .compatible = "fsl,imx7ulp-spi", },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, fsl_lpspi_dt_ids);
#define LPSPI_BUF_RX(type) \
static void fsl_lpspi_buf_rx_##type(struct fsl_lpspi_data *fsl_lpspi) \
{ \
unsigned int val = readl(fsl_lpspi->base + IMX7ULP_RDR); \
\
if (fsl_lpspi->rx_buf) { \
*(type *)fsl_lpspi->rx_buf = val; \
fsl_lpspi->rx_buf += sizeof(type); \
} \
}
#define LPSPI_BUF_TX(type) \
static void fsl_lpspi_buf_tx_##type(struct fsl_lpspi_data *fsl_lpspi) \
{ \
type val = 0; \
\
if (fsl_lpspi->tx_buf) { \
val = *(type *)fsl_lpspi->tx_buf; \
fsl_lpspi->tx_buf += sizeof(type); \
} \
\
fsl_lpspi->remain -= sizeof(type); \
writel(val, fsl_lpspi->base + IMX7ULP_TDR); \
}
LPSPI_BUF_RX(u8)
LPSPI_BUF_TX(u8)
LPSPI_BUF_RX(u16)
LPSPI_BUF_TX(u16)
LPSPI_BUF_RX(u32)
LPSPI_BUF_TX(u32)
static void fsl_lpspi_intctrl(struct fsl_lpspi_data *fsl_lpspi,
unsigned int enable)
{
writel(enable, fsl_lpspi->base + IMX7ULP_IER);
}
static int fsl_lpspi_bytes_per_word(const int bpw)
{
return DIV_ROUND_UP(bpw, BITS_PER_BYTE);
}
static bool fsl_lpspi_can_dma(struct spi_controller *controller,
struct spi_device *spi,
struct spi_transfer *transfer)
{
unsigned int bytes_per_word;
if (!controller->dma_rx)
return false;
bytes_per_word = fsl_lpspi_bytes_per_word(transfer->bits_per_word);
switch (bytes_per_word) {
case 1:
case 2:
case 4:
break;
default:
return false;
}
return true;
}
static int lpspi_prepare_xfer_hardware(struct spi_controller *controller)
{
struct fsl_lpspi_data *fsl_lpspi =
spi_controller_get_devdata(controller);
int ret;
ret = pm_runtime_resume_and_get(fsl_lpspi->dev);
if (ret < 0) {
dev_err(fsl_lpspi->dev, "failed to enable clock\n");
return ret;
}
return 0;
}
static int lpspi_unprepare_xfer_hardware(struct spi_controller *controller)
{
struct fsl_lpspi_data *fsl_lpspi =
spi_controller_get_devdata(controller);
pm_runtime_mark_last_busy(fsl_lpspi->dev);
pm_runtime_put_autosuspend(fsl_lpspi->dev);
return 0;
}
static void fsl_lpspi_write_tx_fifo(struct fsl_lpspi_data *fsl_lpspi)
{
u8 txfifo_cnt;
u32 temp;
txfifo_cnt = readl(fsl_lpspi->base + IMX7ULP_FSR) & 0xff;
while (txfifo_cnt < fsl_lpspi->txfifosize) {
if (!fsl_lpspi->remain)
break;
fsl_lpspi->tx(fsl_lpspi);
txfifo_cnt++;
}
if (txfifo_cnt < fsl_lpspi->txfifosize) {
if (!fsl_lpspi->is_slave) {
temp = readl(fsl_lpspi->base + IMX7ULP_TCR);
temp &= ~TCR_CONTC;
writel(temp, fsl_lpspi->base + IMX7ULP_TCR);
}
fsl_lpspi_intctrl(fsl_lpspi, IER_FCIE);
} else
fsl_lpspi_intctrl(fsl_lpspi, IER_TDIE);
}
static void fsl_lpspi_read_rx_fifo(struct fsl_lpspi_data *fsl_lpspi)
{
while (!(readl(fsl_lpspi->base + IMX7ULP_RSR) & RSR_RXEMPTY))
fsl_lpspi->rx(fsl_lpspi);
}
static void fsl_lpspi_set_cmd(struct fsl_lpspi_data *fsl_lpspi)
{
u32 temp = 0;
temp |= fsl_lpspi->config.bpw - 1;
temp |= (fsl_lpspi->config.mode & 0x3) << 30;
temp |= (fsl_lpspi->config.chip_select & 0x3) << 24;
if (!fsl_lpspi->is_slave) {
temp |= fsl_lpspi->config.prescale << 27;
/*
* Set TCR_CONT will keep SS asserted after current transfer.
* For the first transfer, clear TCR_CONTC to assert SS.
* For subsequent transfer, set TCR_CONTC to keep SS asserted.
*/
if (!fsl_lpspi->usedma) {
temp |= TCR_CONT;
if (fsl_lpspi->is_first_byte)
temp &= ~TCR_CONTC;
else
temp |= TCR_CONTC;
}
}
writel(temp, fsl_lpspi->base + IMX7ULP_TCR);
dev_dbg(fsl_lpspi->dev, "TCR=0x%x\n", temp);
}
static void fsl_lpspi_set_watermark(struct fsl_lpspi_data *fsl_lpspi)
{
u32 temp;
if (!fsl_lpspi->usedma)
temp = fsl_lpspi->watermark >> 1 |
(fsl_lpspi->watermark >> 1) << 16;
else
temp = fsl_lpspi->watermark >> 1;
writel(temp, fsl_lpspi->base + IMX7ULP_FCR);
dev_dbg(fsl_lpspi->dev, "FCR=0x%x\n", temp);
}
static int fsl_lpspi_set_bitrate(struct fsl_lpspi_data *fsl_lpspi)
{
struct lpspi_config config = fsl_lpspi->config;
unsigned int perclk_rate, scldiv;
u8 prescale;
perclk_rate = clk_get_rate(fsl_lpspi->clk_per);
if (config.speed_hz > perclk_rate / 2) {
dev_err(fsl_lpspi->dev,
"per-clk should be at least two times of transfer speed");
return -EINVAL;
}
for (prescale = 0; prescale < 8; prescale++) {
scldiv = perclk_rate / config.speed_hz / (1 << prescale) - 2;
if (scldiv < 256) {
fsl_lpspi->config.prescale = prescale;
break;
}
}
if (scldiv >= 256)
return -EINVAL;
writel(scldiv | (scldiv << 8) | ((scldiv >> 1) << 16),
fsl_lpspi->base + IMX7ULP_CCR);
dev_dbg(fsl_lpspi->dev, "perclk=%d, speed=%d, prescale=%d, scldiv=%d\n",
perclk_rate, config.speed_hz, prescale, scldiv);
return 0;
}
static int fsl_lpspi_dma_configure(struct spi_controller *controller)
{
int ret;
enum dma_slave_buswidth buswidth;
struct dma_slave_config rx = {}, tx = {};
struct fsl_lpspi_data *fsl_lpspi =
spi_controller_get_devdata(controller);
switch (fsl_lpspi_bytes_per_word(fsl_lpspi->config.bpw)) {
case 4:
buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
break;
case 2:
buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
break;
case 1:
buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
break;
default:
return -EINVAL;
}
tx.direction = DMA_MEM_TO_DEV;
tx.dst_addr = fsl_lpspi->base_phys + IMX7ULP_TDR;
tx.dst_addr_width = buswidth;
tx.dst_maxburst = 1;
ret = dmaengine_slave_config(controller->dma_tx, &tx);
if (ret) {
dev_err(fsl_lpspi->dev, "TX dma configuration failed with %d\n",
ret);
return ret;
}
rx.direction = DMA_DEV_TO_MEM;
rx.src_addr = fsl_lpspi->base_phys + IMX7ULP_RDR;
rx.src_addr_width = buswidth;
rx.src_maxburst = 1;
ret = dmaengine_slave_config(controller->dma_rx, &rx);
if (ret) {
dev_err(fsl_lpspi->dev, "RX dma configuration failed with %d\n",
ret);
return ret;
}
return 0;
}
static int fsl_lpspi_config(struct fsl_lpspi_data *fsl_lpspi)
{
u32 temp;
int ret;
if (!fsl_lpspi->is_slave) {
ret = fsl_lpspi_set_bitrate(fsl_lpspi);
if (ret)
return ret;
}
fsl_lpspi_set_watermark(fsl_lpspi);
if (!fsl_lpspi->is_slave)
temp = CFGR1_MASTER;
else
temp = CFGR1_PINCFG;
if (fsl_lpspi->config.mode & SPI_CS_HIGH)
temp |= CFGR1_PCSPOL;
writel(temp, fsl_lpspi->base + IMX7ULP_CFGR1);
temp = readl(fsl_lpspi->base + IMX7ULP_CR);
temp |= CR_RRF | CR_RTF | CR_MEN;
writel(temp, fsl_lpspi->base + IMX7ULP_CR);
temp = 0;
if (fsl_lpspi->usedma)
temp = DER_TDDE | DER_RDDE;
writel(temp, fsl_lpspi->base + IMX7ULP_DER);
return 0;
}
static int fsl_lpspi_setup_transfer(struct spi_controller *controller,
struct spi_device *spi,
struct spi_transfer *t)
{
struct fsl_lpspi_data *fsl_lpspi =
spi_controller_get_devdata(spi->controller);
if (t == NULL)
return -EINVAL;
fsl_lpspi->config.mode = spi->mode;
fsl_lpspi->config.bpw = t->bits_per_word;
fsl_lpspi->config.speed_hz = t->speed_hz;
if (fsl_lpspi->is_only_cs1)
fsl_lpspi->config.chip_select = 1;
else
fsl_lpspi->config.chip_select = spi->chip_select;
if (!fsl_lpspi->config.speed_hz)
fsl_lpspi->config.speed_hz = spi->max_speed_hz;
if (!fsl_lpspi->config.bpw)
fsl_lpspi->config.bpw = spi->bits_per_word;
/* Initialize the functions for transfer */
if (fsl_lpspi->config.bpw <= 8) {
fsl_lpspi->rx = fsl_lpspi_buf_rx_u8;
fsl_lpspi->tx = fsl_lpspi_buf_tx_u8;
} else if (fsl_lpspi->config.bpw <= 16) {
fsl_lpspi->rx = fsl_lpspi_buf_rx_u16;
fsl_lpspi->tx = fsl_lpspi_buf_tx_u16;
} else {
fsl_lpspi->rx = fsl_lpspi_buf_rx_u32;
fsl_lpspi->tx = fsl_lpspi_buf_tx_u32;
}
if (t->len <= fsl_lpspi->txfifosize)
fsl_lpspi->watermark = t->len;
else
fsl_lpspi->watermark = fsl_lpspi->txfifosize;
if (fsl_lpspi_can_dma(controller, spi, t))
fsl_lpspi->usedma = true;
else
fsl_lpspi->usedma = false;
return fsl_lpspi_config(fsl_lpspi);
}
static int fsl_lpspi_slave_abort(struct spi_controller *controller)
{
struct fsl_lpspi_data *fsl_lpspi =
spi_controller_get_devdata(controller);
fsl_lpspi->slave_aborted = true;
if (!fsl_lpspi->usedma)
complete(&fsl_lpspi->xfer_done);
else {
complete(&fsl_lpspi->dma_tx_completion);
complete(&fsl_lpspi->dma_rx_completion);
}
return 0;
}
static int fsl_lpspi_wait_for_completion(struct spi_controller *controller)
{
struct fsl_lpspi_data *fsl_lpspi =
spi_controller_get_devdata(controller);
if (fsl_lpspi->is_slave) {
if (wait_for_completion_interruptible(&fsl_lpspi->xfer_done) ||
fsl_lpspi->slave_aborted) {
dev_dbg(fsl_lpspi->dev, "interrupted\n");
return -EINTR;
}
} else {
if (!wait_for_completion_timeout(&fsl_lpspi->xfer_done, HZ)) {
dev_dbg(fsl_lpspi->dev, "wait for completion timeout\n");
return -ETIMEDOUT;
}
}
return 0;
}
static int fsl_lpspi_reset(struct fsl_lpspi_data *fsl_lpspi)
{
u32 temp;
if (!fsl_lpspi->usedma) {
/* Disable all interrupt */
fsl_lpspi_intctrl(fsl_lpspi, 0);
}
/* W1C for all flags in SR */
temp = 0x3F << 8;
writel(temp, fsl_lpspi->base + IMX7ULP_SR);
/* Clear FIFO and disable module */
temp = CR_RRF | CR_RTF;
writel(temp, fsl_lpspi->base + IMX7ULP_CR);
return 0;
}
static void fsl_lpspi_dma_rx_callback(void *cookie)
{
struct fsl_lpspi_data *fsl_lpspi = (struct fsl_lpspi_data *)cookie;
complete(&fsl_lpspi->dma_rx_completion);
}
static void fsl_lpspi_dma_tx_callback(void *cookie)
{
struct fsl_lpspi_data *fsl_lpspi = (struct fsl_lpspi_data *)cookie;
complete(&fsl_lpspi->dma_tx_completion);
}
static int fsl_lpspi_calculate_timeout(struct fsl_lpspi_data *fsl_lpspi,
int size)
{
unsigned long timeout = 0;
/* Time with actual data transfer and CS change delay related to HW */
timeout = (8 + 4) * size / fsl_lpspi->config.speed_hz;
/* Add extra second for scheduler related activities */
timeout += 1;
/* Double calculated timeout */
return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
}
static int fsl_lpspi_dma_transfer(struct spi_controller *controller,
struct fsl_lpspi_data *fsl_lpspi,
struct spi_transfer *transfer)
{
struct dma_async_tx_descriptor *desc_tx, *desc_rx;
unsigned long transfer_timeout;
unsigned long timeout;
struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
int ret;
ret = fsl_lpspi_dma_configure(controller);
if (ret)
return ret;
desc_rx = dmaengine_prep_slave_sg(controller->dma_rx,
rx->sgl, rx->nents, DMA_DEV_TO_MEM,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc_rx)
return -EINVAL;
desc_rx->callback = fsl_lpspi_dma_rx_callback;
desc_rx->callback_param = (void *)fsl_lpspi;
dmaengine_submit(desc_rx);
reinit_completion(&fsl_lpspi->dma_rx_completion);
dma_async_issue_pending(controller->dma_rx);
desc_tx = dmaengine_prep_slave_sg(controller->dma_tx,
tx->sgl, tx->nents, DMA_MEM_TO_DEV,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc_tx) {
dmaengine_terminate_all(controller->dma_tx);
return -EINVAL;
}
desc_tx->callback = fsl_lpspi_dma_tx_callback;
desc_tx->callback_param = (void *)fsl_lpspi;
dmaengine_submit(desc_tx);
reinit_completion(&fsl_lpspi->dma_tx_completion);
dma_async_issue_pending(controller->dma_tx);
fsl_lpspi->slave_aborted = false;
if (!fsl_lpspi->is_slave) {
transfer_timeout = fsl_lpspi_calculate_timeout(fsl_lpspi,
transfer->len);
/* Wait eDMA to finish the data transfer.*/
timeout = wait_for_completion_timeout(&fsl_lpspi->dma_tx_completion,
transfer_timeout);
if (!timeout) {
dev_err(fsl_lpspi->dev, "I/O Error in DMA TX\n");
dmaengine_terminate_all(controller->dma_tx);
dmaengine_terminate_all(controller->dma_rx);
fsl_lpspi_reset(fsl_lpspi);
return -ETIMEDOUT;
}
timeout = wait_for_completion_timeout(&fsl_lpspi->dma_rx_completion,
transfer_timeout);
if (!timeout) {
dev_err(fsl_lpspi->dev, "I/O Error in DMA RX\n");
dmaengine_terminate_all(controller->dma_tx);
dmaengine_terminate_all(controller->dma_rx);
fsl_lpspi_reset(fsl_lpspi);
return -ETIMEDOUT;
}
} else {
if (wait_for_completion_interruptible(&fsl_lpspi->dma_tx_completion) ||
fsl_lpspi->slave_aborted) {
dev_dbg(fsl_lpspi->dev,
"I/O Error in DMA TX interrupted\n");
dmaengine_terminate_all(controller->dma_tx);
dmaengine_terminate_all(controller->dma_rx);
fsl_lpspi_reset(fsl_lpspi);
return -EINTR;
}
if (wait_for_completion_interruptible(&fsl_lpspi->dma_rx_completion) ||
fsl_lpspi->slave_aborted) {
dev_dbg(fsl_lpspi->dev,
"I/O Error in DMA RX interrupted\n");
dmaengine_terminate_all(controller->dma_tx);
dmaengine_terminate_all(controller->dma_rx);
fsl_lpspi_reset(fsl_lpspi);
return -EINTR;
}
}
fsl_lpspi_reset(fsl_lpspi);
return 0;
}
static void fsl_lpspi_dma_exit(struct spi_controller *controller)
{
if (controller->dma_rx) {
dma_release_channel(controller->dma_rx);
controller->dma_rx = NULL;
}
if (controller->dma_tx) {
dma_release_channel(controller->dma_tx);
controller->dma_tx = NULL;
}
}
static int fsl_lpspi_dma_init(struct device *dev,
struct fsl_lpspi_data *fsl_lpspi,
struct spi_controller *controller)
{
int ret;
/* Prepare for TX DMA: */
controller->dma_tx = dma_request_chan(dev, "tx");
if (IS_ERR(controller->dma_tx)) {
ret = PTR_ERR(controller->dma_tx);
dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
controller->dma_tx = NULL;
goto err;
}
/* Prepare for RX DMA: */
controller->dma_rx = dma_request_chan(dev, "rx");
if (IS_ERR(controller->dma_rx)) {
ret = PTR_ERR(controller->dma_rx);
dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
controller->dma_rx = NULL;
goto err;
}
init_completion(&fsl_lpspi->dma_rx_completion);
init_completion(&fsl_lpspi->dma_tx_completion);
controller->can_dma = fsl_lpspi_can_dma;
controller->max_dma_len = FSL_LPSPI_MAX_EDMA_BYTES;
return 0;
err:
fsl_lpspi_dma_exit(controller);
return ret;
}
static int fsl_lpspi_pio_transfer(struct spi_controller *controller,
struct spi_transfer *t)
{
struct fsl_lpspi_data *fsl_lpspi =
spi_controller_get_devdata(controller);
int ret;
fsl_lpspi->tx_buf = t->tx_buf;
fsl_lpspi->rx_buf = t->rx_buf;
fsl_lpspi->remain = t->len;
reinit_completion(&fsl_lpspi->xfer_done);
fsl_lpspi->slave_aborted = false;
fsl_lpspi_write_tx_fifo(fsl_lpspi);
ret = fsl_lpspi_wait_for_completion(controller);
if (ret)
return ret;
fsl_lpspi_reset(fsl_lpspi);
return 0;
}
static int fsl_lpspi_transfer_one(struct spi_controller *controller,
struct spi_device *spi,
struct spi_transfer *t)
{
struct fsl_lpspi_data *fsl_lpspi =
spi_controller_get_devdata(controller);
int ret;
fsl_lpspi->is_first_byte = true;
ret = fsl_lpspi_setup_transfer(controller, spi, t);
if (ret < 0)
return ret;
fsl_lpspi_set_cmd(fsl_lpspi);
fsl_lpspi->is_first_byte = false;
if (fsl_lpspi->usedma)
ret = fsl_lpspi_dma_transfer(controller, fsl_lpspi, t);
else
ret = fsl_lpspi_pio_transfer(controller, t);
if (ret < 0)
return ret;
return 0;
}
static irqreturn_t fsl_lpspi_isr(int irq, void *dev_id)
{
u32 temp_SR, temp_IER;
struct fsl_lpspi_data *fsl_lpspi = dev_id;
temp_IER = readl(fsl_lpspi->base + IMX7ULP_IER);
fsl_lpspi_intctrl(fsl_lpspi, 0);
temp_SR = readl(fsl_lpspi->base + IMX7ULP_SR);
fsl_lpspi_read_rx_fifo(fsl_lpspi);
if ((temp_SR & SR_TDF) && (temp_IER & IER_TDIE)) {
fsl_lpspi_write_tx_fifo(fsl_lpspi);
return IRQ_HANDLED;
}
if (temp_SR & SR_MBF ||
readl(fsl_lpspi->base + IMX7ULP_FSR) & FSR_TXCOUNT) {
writel(SR_FCF, fsl_lpspi->base + IMX7ULP_SR);
fsl_lpspi_intctrl(fsl_lpspi, IER_FCIE);
return IRQ_HANDLED;
}
if (temp_SR & SR_FCF && (temp_IER & IER_FCIE)) {
writel(SR_FCF, fsl_lpspi->base + IMX7ULP_SR);
complete(&fsl_lpspi->xfer_done);
return IRQ_HANDLED;
}
return IRQ_NONE;
}
#ifdef CONFIG_PM
static int fsl_lpspi_runtime_resume(struct device *dev)
{
struct spi_controller *controller = dev_get_drvdata(dev);
struct fsl_lpspi_data *fsl_lpspi;
int ret;
fsl_lpspi = spi_controller_get_devdata(controller);
ret = clk_prepare_enable(fsl_lpspi->clk_per);
if (ret)
return ret;
ret = clk_prepare_enable(fsl_lpspi->clk_ipg);
if (ret) {
clk_disable_unprepare(fsl_lpspi->clk_per);
return ret;
}
return 0;
}
static int fsl_lpspi_runtime_suspend(struct device *dev)
{
struct spi_controller *controller = dev_get_drvdata(dev);
struct fsl_lpspi_data *fsl_lpspi;
fsl_lpspi = spi_controller_get_devdata(controller);
clk_disable_unprepare(fsl_lpspi->clk_per);
clk_disable_unprepare(fsl_lpspi->clk_ipg);
return 0;
}
#endif
static int fsl_lpspi_init_rpm(struct fsl_lpspi_data *fsl_lpspi)
{
struct device *dev = fsl_lpspi->dev;
pm_runtime_enable(dev);
pm_runtime_set_autosuspend_delay(dev, FSL_LPSPI_RPM_TIMEOUT);
pm_runtime_use_autosuspend(dev);
return 0;
}
static int fsl_lpspi_probe(struct platform_device *pdev)
{
struct fsl_lpspi_data *fsl_lpspi;
struct spi_controller *controller;
struct resource *res;
int ret, irq;
u32 temp;
bool is_slave;
is_slave = of_property_read_bool((&pdev->dev)->of_node, "spi-slave");
if (is_slave)
controller = spi_alloc_slave(&pdev->dev,
sizeof(struct fsl_lpspi_data));
else
controller = spi_alloc_master(&pdev->dev,
sizeof(struct fsl_lpspi_data));
if (!controller)
return -ENOMEM;
platform_set_drvdata(pdev, controller);
fsl_lpspi = spi_controller_get_devdata(controller);
fsl_lpspi->dev = &pdev->dev;
fsl_lpspi->is_slave = is_slave;
fsl_lpspi->is_only_cs1 = of_property_read_bool((&pdev->dev)->of_node,
"fsl,spi-only-use-cs1-sel");
if (of_property_read_u32((&pdev->dev)->of_node, "num-cs",
&fsl_lpspi->num_cs))
fsl_lpspi->num_cs = 1;
controller->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 32);
controller->transfer_one = fsl_lpspi_transfer_one;
controller->prepare_transfer_hardware = lpspi_prepare_xfer_hardware;
controller->unprepare_transfer_hardware = lpspi_unprepare_xfer_hardware;
controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
controller->flags = SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX;
controller->dev.of_node = pdev->dev.of_node;
controller->bus_num = pdev->id;
controller->num_chipselect = fsl_lpspi->num_cs;
controller->slave_abort = fsl_lpspi_slave_abort;
if (!fsl_lpspi->is_slave)
controller->use_gpio_descriptors = true;
init_completion(&fsl_lpspi->xfer_done);
fsl_lpspi->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
if (IS_ERR(fsl_lpspi->base)) {
ret = PTR_ERR(fsl_lpspi->base);
goto out_controller_put;
}
fsl_lpspi->base_phys = res->start;
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
ret = irq;
goto out_controller_put;
}
ret = devm_request_irq(&pdev->dev, irq, fsl_lpspi_isr, 0,
dev_name(&pdev->dev), fsl_lpspi);
if (ret) {
dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
goto out_controller_put;
}
fsl_lpspi->clk_per = devm_clk_get(&pdev->dev, "per");
if (IS_ERR(fsl_lpspi->clk_per)) {
ret = PTR_ERR(fsl_lpspi->clk_per);
goto out_controller_put;
}
fsl_lpspi->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
if (IS_ERR(fsl_lpspi->clk_ipg)) {
ret = PTR_ERR(fsl_lpspi->clk_ipg);
goto out_controller_put;
}
/* enable the clock */
ret = fsl_lpspi_init_rpm(fsl_lpspi);
if (ret)
goto out_controller_put;
ret = pm_runtime_get_sync(fsl_lpspi->dev);
if (ret < 0) {
dev_err(fsl_lpspi->dev, "failed to enable clock\n");
goto out_pm_get;
}
temp = readl(fsl_lpspi->base + IMX7ULP_PARAM);
fsl_lpspi->txfifosize = 1 << (temp & 0x0f);
fsl_lpspi->rxfifosize = 1 << ((temp >> 8) & 0x0f);
ret = fsl_lpspi_dma_init(&pdev->dev, fsl_lpspi, controller);
if (ret == -EPROBE_DEFER)
goto out_pm_get;
if (ret < 0)
dev_err(&pdev->dev, "dma setup error %d, use pio\n", ret);
ret = devm_spi_register_controller(&pdev->dev, controller);
if (ret < 0) {
dev_err_probe(&pdev->dev, ret, "spi_register_controller error\n");
goto free_dma;
}
pm_runtime_mark_last_busy(fsl_lpspi->dev);
pm_runtime_put_autosuspend(fsl_lpspi->dev);
return 0;
free_dma:
fsl_lpspi_dma_exit(controller);
out_pm_get:
pm_runtime_dont_use_autosuspend(fsl_lpspi->dev);
pm_runtime_put_sync(fsl_lpspi->dev);
pm_runtime_disable(fsl_lpspi->dev);
out_controller_put:
spi_controller_put(controller);
return ret;
}
static void fsl_lpspi_remove(struct platform_device *pdev)
{
struct spi_controller *controller = platform_get_drvdata(pdev);
struct fsl_lpspi_data *fsl_lpspi =
spi_controller_get_devdata(controller);
fsl_lpspi_dma_exit(controller);
pm_runtime_disable(fsl_lpspi->dev);
}
static int __maybe_unused fsl_lpspi_suspend(struct device *dev)
{
pinctrl_pm_select_sleep_state(dev);
return pm_runtime_force_suspend(dev);
}
static int __maybe_unused fsl_lpspi_resume(struct device *dev)
{
int ret;
ret = pm_runtime_force_resume(dev);
if (ret) {
dev_err(dev, "Error in resume: %d\n", ret);
return ret;
}
pinctrl_pm_select_default_state(dev);
return 0;
}
static const struct dev_pm_ops fsl_lpspi_pm_ops = {
SET_RUNTIME_PM_OPS(fsl_lpspi_runtime_suspend,
fsl_lpspi_runtime_resume, NULL)
SET_SYSTEM_SLEEP_PM_OPS(fsl_lpspi_suspend, fsl_lpspi_resume)
};
static struct platform_driver fsl_lpspi_driver = {
.driver = {
.name = DRIVER_NAME,
.of_match_table = fsl_lpspi_dt_ids,
.pm = &fsl_lpspi_pm_ops,
},
.probe = fsl_lpspi_probe,
.remove_new = fsl_lpspi_remove,
};
module_platform_driver(fsl_lpspi_driver);
MODULE_DESCRIPTION("LPSPI Controller driver");
MODULE_AUTHOR("Gao Pan <pandy.gao@nxp.com>");
MODULE_LICENSE("GPL");