- 根目录:
- drivers
- spi
- spi-sirf.c
/*
* SPI bus driver for CSR SiRFprimaII
*
* Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
*
* Licensed under GPLv2 or later.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/clk.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/bitops.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/of_gpio.h>
#include <linux/spi/spi.h>
#include <linux/spi/spi_bitbang.h>
#include <linux/dmaengine.h>
#include <linux/dma-direction.h>
#include <linux/dma-mapping.h>
#include <linux/sirfsoc_dma.h>
#define DRIVER_NAME "sirfsoc_spi"
#define SIRFSOC_SPI_CTRL 0x0000
#define SIRFSOC_SPI_CMD 0x0004
#define SIRFSOC_SPI_TX_RX_EN 0x0008
#define SIRFSOC_SPI_INT_EN 0x000C
#define SIRFSOC_SPI_INT_STATUS 0x0010
#define SIRFSOC_SPI_TX_DMA_IO_CTRL 0x0100
#define SIRFSOC_SPI_TX_DMA_IO_LEN 0x0104
#define SIRFSOC_SPI_TXFIFO_CTRL 0x0108
#define SIRFSOC_SPI_TXFIFO_LEVEL_CHK 0x010C
#define SIRFSOC_SPI_TXFIFO_OP 0x0110
#define SIRFSOC_SPI_TXFIFO_STATUS 0x0114
#define SIRFSOC_SPI_TXFIFO_DATA 0x0118
#define SIRFSOC_SPI_RX_DMA_IO_CTRL 0x0120
#define SIRFSOC_SPI_RX_DMA_IO_LEN 0x0124
#define SIRFSOC_SPI_RXFIFO_CTRL 0x0128
#define SIRFSOC_SPI_RXFIFO_LEVEL_CHK 0x012C
#define SIRFSOC_SPI_RXFIFO_OP 0x0130
#define SIRFSOC_SPI_RXFIFO_STATUS 0x0134
#define SIRFSOC_SPI_RXFIFO_DATA 0x0138
#define SIRFSOC_SPI_DUMMY_DELAY_CTL 0x0144
/* SPI CTRL register defines */
#define SIRFSOC_SPI_SLV_MODE BIT(16)
#define SIRFSOC_SPI_CMD_MODE BIT(17)
#define SIRFSOC_SPI_CS_IO_OUT BIT(18)
#define SIRFSOC_SPI_CS_IO_MODE BIT(19)
#define SIRFSOC_SPI_CLK_IDLE_STAT BIT(20)
#define SIRFSOC_SPI_CS_IDLE_STAT BIT(21)
#define SIRFSOC_SPI_TRAN_MSB BIT(22)
#define SIRFSOC_SPI_DRV_POS_EDGE BIT(23)
#define SIRFSOC_SPI_CS_HOLD_TIME BIT(24)
#define SIRFSOC_SPI_CLK_SAMPLE_MODE BIT(25)
#define SIRFSOC_SPI_TRAN_DAT_FORMAT_8 (0 << 26)
#define SIRFSOC_SPI_TRAN_DAT_FORMAT_12 (1 << 26)
#define SIRFSOC_SPI_TRAN_DAT_FORMAT_16 (2 << 26)
#define SIRFSOC_SPI_TRAN_DAT_FORMAT_32 (3 << 26)
#define SIRFSOC_SPI_CMD_BYTE_NUM(x) ((x & 3) << 28)
#define SIRFSOC_SPI_ENA_AUTO_CLR BIT(30)
#define SIRFSOC_SPI_MUL_DAT_MODE BIT(31)
/* Interrupt Enable */
#define SIRFSOC_SPI_RX_DONE_INT_EN BIT(0)
#define SIRFSOC_SPI_TX_DONE_INT_EN BIT(1)
#define SIRFSOC_SPI_RX_OFLOW_INT_EN BIT(2)
#define SIRFSOC_SPI_TX_UFLOW_INT_EN BIT(3)
#define SIRFSOC_SPI_RX_IO_DMA_INT_EN BIT(4)
#define SIRFSOC_SPI_TX_IO_DMA_INT_EN BIT(5)
#define SIRFSOC_SPI_RXFIFO_FULL_INT_EN BIT(6)
#define SIRFSOC_SPI_TXFIFO_EMPTY_INT_EN BIT(7)
#define SIRFSOC_SPI_RXFIFO_THD_INT_EN BIT(8)
#define SIRFSOC_SPI_TXFIFO_THD_INT_EN BIT(9)
#define SIRFSOC_SPI_FRM_END_INT_EN BIT(10)
#define SIRFSOC_SPI_INT_MASK_ALL 0x1FFF
/* Interrupt status */
#define SIRFSOC_SPI_RX_DONE BIT(0)
#define SIRFSOC_SPI_TX_DONE BIT(1)
#define SIRFSOC_SPI_RX_OFLOW BIT(2)
#define SIRFSOC_SPI_TX_UFLOW BIT(3)
#define SIRFSOC_SPI_RX_FIFO_FULL BIT(6)
#define SIRFSOC_SPI_TXFIFO_EMPTY BIT(7)
#define SIRFSOC_SPI_RXFIFO_THD_REACH BIT(8)
#define SIRFSOC_SPI_TXFIFO_THD_REACH BIT(9)
#define SIRFSOC_SPI_FRM_END BIT(10)
/* TX RX enable */
#define SIRFSOC_SPI_RX_EN BIT(0)
#define SIRFSOC_SPI_TX_EN BIT(1)
#define SIRFSOC_SPI_CMD_TX_EN BIT(2)
#define SIRFSOC_SPI_IO_MODE_SEL BIT(0)
#define SIRFSOC_SPI_RX_DMA_FLUSH BIT(2)
/* FIFO OPs */
#define SIRFSOC_SPI_FIFO_RESET BIT(0)
#define SIRFSOC_SPI_FIFO_START BIT(1)
/* FIFO CTRL */
#define SIRFSOC_SPI_FIFO_WIDTH_BYTE (0 << 0)
#define SIRFSOC_SPI_FIFO_WIDTH_WORD (1 << 0)
#define SIRFSOC_SPI_FIFO_WIDTH_DWORD (2 << 0)
/* FIFO Status */
#define SIRFSOC_SPI_FIFO_LEVEL_MASK 0xFF
#define SIRFSOC_SPI_FIFO_FULL BIT(8)
#define SIRFSOC_SPI_FIFO_EMPTY BIT(9)
/* 256 bytes rx/tx FIFO */
#define SIRFSOC_SPI_FIFO_SIZE 256
#define SIRFSOC_SPI_DAT_FRM_LEN_MAX (64 * 1024)
#define SIRFSOC_SPI_FIFO_SC(x) ((x) & 0x3F)
#define SIRFSOC_SPI_FIFO_LC(x) (((x) & 0x3F) << 10)
#define SIRFSOC_SPI_FIFO_HC(x) (((x) & 0x3F) << 20)
#define SIRFSOC_SPI_FIFO_THD(x) (((x) & 0xFF) << 2)
/*
* only if the rx/tx buffer and transfer size are 4-bytes aligned, we use dma
* due to the limitation of dma controller
*/
#define ALIGNED(x) (!((u32)x & 0x3))
#define IS_DMA_VALID(x) (x && ALIGNED(x->tx_buf) && ALIGNED(x->rx_buf) && \
ALIGNED(x->len) && (x->len < 2 * PAGE_SIZE))
struct sirfsoc_spi {
struct spi_bitbang bitbang;
struct completion rx_done;
struct completion tx_done;
void __iomem *base;
u32 ctrl_freq; /* SPI controller clock speed */
struct clk *clk;
/* rx & tx bufs from the spi_transfer */
const void *tx;
void *rx;
/* place received word into rx buffer */
void (*rx_word) (struct sirfsoc_spi *);
/* get word from tx buffer for sending */
void (*tx_word) (struct sirfsoc_spi *);
/* number of words left to be tranmitted/received */
unsigned int left_tx_word;
unsigned int left_rx_word;
/* rx & tx DMA channels */
struct dma_chan *rx_chan;
struct dma_chan *tx_chan;
dma_addr_t src_start;
dma_addr_t dst_start;
void *dummypage;
int word_width; /* in bytes */
int chipselect[0];
};
static void spi_sirfsoc_rx_word_u8(struct sirfsoc_spi *sspi)
{
u32 data;
u8 *rx = sspi->rx;
data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA);
if (rx) {
*rx++ = (u8) data;
sspi->rx = rx;
}
sspi->left_rx_word--;
}
static void spi_sirfsoc_tx_word_u8(struct sirfsoc_spi *sspi)
{
u32 data = 0;
const u8 *tx = sspi->tx;
if (tx) {
data = *tx++;
sspi->tx = tx;
}
writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
sspi->left_tx_word--;
}
static void spi_sirfsoc_rx_word_u16(struct sirfsoc_spi *sspi)
{
u32 data;
u16 *rx = sspi->rx;
data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA);
if (rx) {
*rx++ = (u16) data;
sspi->rx = rx;
}
sspi->left_rx_word--;
}
static void spi_sirfsoc_tx_word_u16(struct sirfsoc_spi *sspi)
{
u32 data = 0;
const u16 *tx = sspi->tx;
if (tx) {
data = *tx++;
sspi->tx = tx;
}
writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
sspi->left_tx_word--;
}
static void spi_sirfsoc_rx_word_u32(struct sirfsoc_spi *sspi)
{
u32 data;
u32 *rx = sspi->rx;
data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA);
if (rx) {
*rx++ = (u32) data;
sspi->rx = rx;
}
sspi->left_rx_word--;
}
static void spi_sirfsoc_tx_word_u32(struct sirfsoc_spi *sspi)
{
u32 data = 0;
const u32 *tx = sspi->tx;
if (tx) {
data = *tx++;
sspi->tx = tx;
}
writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
sspi->left_tx_word--;
}
static irqreturn_t spi_sirfsoc_irq(int irq, void *dev_id)
{
struct sirfsoc_spi *sspi = dev_id;
u32 spi_stat = readl(sspi->base + SIRFSOC_SPI_INT_STATUS);
writel(spi_stat, sspi->base + SIRFSOC_SPI_INT_STATUS);
/* Error Conditions */
if (spi_stat & SIRFSOC_SPI_RX_OFLOW ||
spi_stat & SIRFSOC_SPI_TX_UFLOW) {
complete(&sspi->rx_done);
writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN);
}
if (spi_stat & (SIRFSOC_SPI_FRM_END
| SIRFSOC_SPI_RXFIFO_THD_REACH))
while (!((readl(sspi->base + SIRFSOC_SPI_RXFIFO_STATUS)
& SIRFSOC_SPI_FIFO_EMPTY)) &&
sspi->left_rx_word)
sspi->rx_word(sspi);
if (spi_stat & (SIRFSOC_SPI_FIFO_EMPTY
| SIRFSOC_SPI_TXFIFO_THD_REACH))
while (!((readl(sspi->base + SIRFSOC_SPI_TXFIFO_STATUS)
& SIRFSOC_SPI_FIFO_FULL)) &&
sspi->left_tx_word)
sspi->tx_word(sspi);
/* Received all words */
if ((sspi->left_rx_word == 0) && (sspi->left_tx_word == 0)) {
complete(&sspi->rx_done);
writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN);
}
return IRQ_HANDLED;
}
static void spi_sirfsoc_dma_fini_callback(void *data)
{
struct completion *dma_complete = data;
complete(dma_complete);
}
static int spi_sirfsoc_transfer(struct spi_device *spi, struct spi_transfer *t)
{
struct sirfsoc_spi *sspi;
int timeout = t->len * 10;
sspi = spi_master_get_devdata(spi->master);
sspi->tx = t->tx_buf ? t->tx_buf : sspi->dummypage;
sspi->rx = t->rx_buf ? t->rx_buf : sspi->dummypage;
sspi->left_tx_word = sspi->left_rx_word = t->len / sspi->word_width;
reinit_completion(&sspi->rx_done);
reinit_completion(&sspi->tx_done);
writel(SIRFSOC_SPI_INT_MASK_ALL, sspi->base + SIRFSOC_SPI_INT_STATUS);
if (sspi->left_tx_word == 1) {
writel(readl(sspi->base + SIRFSOC_SPI_CTRL) |
SIRFSOC_SPI_ENA_AUTO_CLR,
sspi->base + SIRFSOC_SPI_CTRL);
writel(0, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
writel(0, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
} else if ((sspi->left_tx_word > 1) && (sspi->left_tx_word <
SIRFSOC_SPI_DAT_FRM_LEN_MAX)) {
writel(readl(sspi->base + SIRFSOC_SPI_CTRL) |
SIRFSOC_SPI_MUL_DAT_MODE |
SIRFSOC_SPI_ENA_AUTO_CLR,
sspi->base + SIRFSOC_SPI_CTRL);
writel(sspi->left_tx_word - 1,
sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
writel(sspi->left_tx_word - 1,
sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
} else {
writel(readl(sspi->base + SIRFSOC_SPI_CTRL),
sspi->base + SIRFSOC_SPI_CTRL);
writel(0, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
writel(0, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
}
writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
if (IS_DMA_VALID(t)) {
struct dma_async_tx_descriptor *rx_desc, *tx_desc;
sspi->dst_start = dma_map_single(&spi->dev, sspi->rx, t->len, DMA_FROM_DEVICE);
rx_desc = dmaengine_prep_slave_single(sspi->rx_chan,
sspi->dst_start, t->len, DMA_DEV_TO_MEM,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
rx_desc->callback = spi_sirfsoc_dma_fini_callback;
rx_desc->callback_param = &sspi->rx_done;
sspi->src_start = dma_map_single(&spi->dev, (void *)sspi->tx, t->len, DMA_TO_DEVICE);
tx_desc = dmaengine_prep_slave_single(sspi->tx_chan,
sspi->src_start, t->len, DMA_MEM_TO_DEV,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
tx_desc->callback = spi_sirfsoc_dma_fini_callback;
tx_desc->callback_param = &sspi->tx_done;
dmaengine_submit(tx_desc);
dmaengine_submit(rx_desc);
dma_async_issue_pending(sspi->tx_chan);
dma_async_issue_pending(sspi->rx_chan);
} else {
/* Send the first word to trigger the whole tx/rx process */
sspi->tx_word(sspi);
writel(SIRFSOC_SPI_RX_OFLOW_INT_EN | SIRFSOC_SPI_TX_UFLOW_INT_EN |
SIRFSOC_SPI_RXFIFO_THD_INT_EN | SIRFSOC_SPI_TXFIFO_THD_INT_EN |
SIRFSOC_SPI_FRM_END_INT_EN | SIRFSOC_SPI_RXFIFO_FULL_INT_EN |
SIRFSOC_SPI_TXFIFO_EMPTY_INT_EN, sspi->base + SIRFSOC_SPI_INT_EN);
}
writel(SIRFSOC_SPI_RX_EN | SIRFSOC_SPI_TX_EN, sspi->base + SIRFSOC_SPI_TX_RX_EN);
if (!IS_DMA_VALID(t)) { /* for PIO */
if (wait_for_completion_timeout(&sspi->rx_done, timeout) == 0)
dev_err(&spi->dev, "transfer timeout\n");
} else if (wait_for_completion_timeout(&sspi->rx_done, timeout) == 0) {
dev_err(&spi->dev, "transfer timeout\n");
dmaengine_terminate_all(sspi->rx_chan);
} else
sspi->left_rx_word = 0;
/*
* we only wait tx-done event if transferring by DMA. for PIO,
* we get rx data by writing tx data, so if rx is done, tx has
* done earlier
*/
if (IS_DMA_VALID(t)) {
if (wait_for_completion_timeout(&sspi->tx_done, timeout) == 0) {
dev_err(&spi->dev, "transfer timeout\n");
dmaengine_terminate_all(sspi->tx_chan);
}
}
if (IS_DMA_VALID(t)) {
dma_unmap_single(&spi->dev, sspi->src_start, t->len, DMA_TO_DEVICE);
dma_unmap_single(&spi->dev, sspi->dst_start, t->len, DMA_FROM_DEVICE);
}
/* TX, RX FIFO stop */
writel(0, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
writel(0, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
writel(0, sspi->base + SIRFSOC_SPI_TX_RX_EN);
writel(0, sspi->base + SIRFSOC_SPI_INT_EN);
return t->len - sspi->left_rx_word * sspi->word_width;
}
static void spi_sirfsoc_chipselect(struct spi_device *spi, int value)
{
struct sirfsoc_spi *sspi = spi_master_get_devdata(spi->master);
if (sspi->chipselect[spi->chip_select] == 0) {
u32 regval = readl(sspi->base + SIRFSOC_SPI_CTRL);
switch (value) {
case BITBANG_CS_ACTIVE:
if (spi->mode & SPI_CS_HIGH)
regval |= SIRFSOC_SPI_CS_IO_OUT;
else
regval &= ~SIRFSOC_SPI_CS_IO_OUT;
break;
case BITBANG_CS_INACTIVE:
if (spi->mode & SPI_CS_HIGH)
regval &= ~SIRFSOC_SPI_CS_IO_OUT;
else
regval |= SIRFSOC_SPI_CS_IO_OUT;
break;
}
writel(regval, sspi->base + SIRFSOC_SPI_CTRL);
} else {
int gpio = sspi->chipselect[spi->chip_select];
gpio_direction_output(gpio, spi->mode & SPI_CS_HIGH ? 0 : 1);
}
}
static int
spi_sirfsoc_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
{
struct sirfsoc_spi *sspi;
u8 bits_per_word = 0;
int hz = 0;
u32 regval;
u32 txfifo_ctrl, rxfifo_ctrl;
u32 fifo_size = SIRFSOC_SPI_FIFO_SIZE / 4;
sspi = spi_master_get_devdata(spi->master);
bits_per_word = (t) ? t->bits_per_word : spi->bits_per_word;
hz = t && t->speed_hz ? t->speed_hz : spi->max_speed_hz;
regval = (sspi->ctrl_freq / (2 * hz)) - 1;
if (regval > 0xFFFF || regval < 0) {
dev_err(&spi->dev, "Speed %d not supported\n", hz);
return -EINVAL;
}
switch (bits_per_word) {
case 8:
regval |= SIRFSOC_SPI_TRAN_DAT_FORMAT_8;
sspi->rx_word = spi_sirfsoc_rx_word_u8;
sspi->tx_word = spi_sirfsoc_tx_word_u8;
txfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
SIRFSOC_SPI_FIFO_WIDTH_BYTE;
rxfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
SIRFSOC_SPI_FIFO_WIDTH_BYTE;
sspi->word_width = 1;
break;
case 12:
case 16:
regval |= (bits_per_word == 12) ? SIRFSOC_SPI_TRAN_DAT_FORMAT_12 :
SIRFSOC_SPI_TRAN_DAT_FORMAT_16;
sspi->rx_word = spi_sirfsoc_rx_word_u16;
sspi->tx_word = spi_sirfsoc_tx_word_u16;
txfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
SIRFSOC_SPI_FIFO_WIDTH_WORD;
rxfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
SIRFSOC_SPI_FIFO_WIDTH_WORD;
sspi->word_width = 2;
break;
case 32:
regval |= SIRFSOC_SPI_TRAN_DAT_FORMAT_32;
sspi->rx_word = spi_sirfsoc_rx_word_u32;
sspi->tx_word = spi_sirfsoc_tx_word_u32;
txfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
SIRFSOC_SPI_FIFO_WIDTH_DWORD;
rxfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
SIRFSOC_SPI_FIFO_WIDTH_DWORD;
sspi->word_width = 4;
break;
default:
BUG();
}
if (!(spi->mode & SPI_CS_HIGH))
regval |= SIRFSOC_SPI_CS_IDLE_STAT;
if (!(spi->mode & SPI_LSB_FIRST))
regval |= SIRFSOC_SPI_TRAN_MSB;
if (spi->mode & SPI_CPOL)
regval |= SIRFSOC_SPI_CLK_IDLE_STAT;
/*
* Data should be driven at least 1/2 cycle before the fetch edge to make
* sure that data gets stable at the fetch edge.
*/
if (((spi->mode & SPI_CPOL) && (spi->mode & SPI_CPHA)) ||
(!(spi->mode & SPI_CPOL) && !(spi->mode & SPI_CPHA)))
regval &= ~SIRFSOC_SPI_DRV_POS_EDGE;
else
regval |= SIRFSOC_SPI_DRV_POS_EDGE;
writel(SIRFSOC_SPI_FIFO_SC(fifo_size - 2) |
SIRFSOC_SPI_FIFO_LC(fifo_size / 2) |
SIRFSOC_SPI_FIFO_HC(2),
sspi->base + SIRFSOC_SPI_TXFIFO_LEVEL_CHK);
writel(SIRFSOC_SPI_FIFO_SC(2) |
SIRFSOC_SPI_FIFO_LC(fifo_size / 2) |
SIRFSOC_SPI_FIFO_HC(fifo_size - 2),
sspi->base + SIRFSOC_SPI_RXFIFO_LEVEL_CHK);
writel(txfifo_ctrl, sspi->base + SIRFSOC_SPI_TXFIFO_CTRL);
writel(rxfifo_ctrl, sspi->base + SIRFSOC_SPI_RXFIFO_CTRL);
writel(regval, sspi->base + SIRFSOC_SPI_CTRL);
if (IS_DMA_VALID(t)) {
/* Enable DMA mode for RX, TX */
writel(0, sspi->base + SIRFSOC_SPI_TX_DMA_IO_CTRL);
writel(SIRFSOC_SPI_RX_DMA_FLUSH, sspi->base + SIRFSOC_SPI_RX_DMA_IO_CTRL);
} else {
/* Enable IO mode for RX, TX */
writel(SIRFSOC_SPI_IO_MODE_SEL, sspi->base + SIRFSOC_SPI_TX_DMA_IO_CTRL);
writel(SIRFSOC_SPI_IO_MODE_SEL, sspi->base + SIRFSOC_SPI_RX_DMA_IO_CTRL);
}
return 0;
}
static int spi_sirfsoc_setup(struct spi_device *spi)
{
if (!spi->max_speed_hz)
return -EINVAL;
return spi_sirfsoc_setup_transfer(spi, NULL);
}
static int spi_sirfsoc_probe(struct platform_device *pdev)
{
struct sirfsoc_spi *sspi;
struct spi_master *master;
struct resource *mem_res;
int num_cs, cs_gpio, irq;
u32 rx_dma_ch, tx_dma_ch;
dma_cap_mask_t dma_cap_mask;
int i;
int ret;
ret = of_property_read_u32(pdev->dev.of_node,
"sirf,spi-num-chipselects", &num_cs);
if (ret < 0) {
dev_err(&pdev->dev, "Unable to get chip select number\n");
goto err_cs;
}
ret = of_property_read_u32(pdev->dev.of_node,
"sirf,spi-dma-rx-channel", &rx_dma_ch);
if (ret < 0) {
dev_err(&pdev->dev, "Unable to get rx dma channel\n");
goto err_cs;
}
ret = of_property_read_u32(pdev->dev.of_node,
"sirf,spi-dma-tx-channel", &tx_dma_ch);
if (ret < 0) {
dev_err(&pdev->dev, "Unable to get tx dma channel\n");
goto err_cs;
}
master = spi_alloc_master(&pdev->dev, sizeof(*sspi) + sizeof(int) * num_cs);
if (!master) {
dev_err(&pdev->dev, "Unable to allocate SPI master\n");
return -ENOMEM;
}
platform_set_drvdata(pdev, master);
sspi = spi_master_get_devdata(master);
master->num_chipselect = num_cs;
for (i = 0; i < master->num_chipselect; i++) {
cs_gpio = of_get_named_gpio(pdev->dev.of_node, "cs-gpios", i);
if (cs_gpio < 0) {
dev_err(&pdev->dev, "can't get cs gpio from DT\n");
ret = -ENODEV;
goto free_master;
}
sspi->chipselect[i] = cs_gpio;
if (cs_gpio == 0)
continue; /* use cs from spi controller */
ret = gpio_request(cs_gpio, DRIVER_NAME);
if (ret) {
while (i > 0) {
i--;
if (sspi->chipselect[i] > 0)
gpio_free(sspi->chipselect[i]);
}
dev_err(&pdev->dev, "fail to request cs gpios\n");
goto free_master;
}
}
mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
sspi->base = devm_ioremap_resource(&pdev->dev, mem_res);
if (IS_ERR(sspi->base)) {
ret = PTR_ERR(sspi->base);
goto free_master;
}
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
ret = -ENXIO;
goto free_master;
}
ret = devm_request_irq(&pdev->dev, irq, spi_sirfsoc_irq, 0,
DRIVER_NAME, sspi);
if (ret)
goto free_master;
sspi->bitbang.master = master;
sspi->bitbang.chipselect = spi_sirfsoc_chipselect;
sspi->bitbang.setup_transfer = spi_sirfsoc_setup_transfer;
sspi->bitbang.txrx_bufs = spi_sirfsoc_transfer;
sspi->bitbang.master->setup = spi_sirfsoc_setup;
master->bus_num = pdev->id;
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST | SPI_CS_HIGH;
master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(12) |
SPI_BPW_MASK(16) | SPI_BPW_MASK(32);
sspi->bitbang.master->dev.of_node = pdev->dev.of_node;
/* request DMA channels */
dma_cap_zero(dma_cap_mask);
dma_cap_set(DMA_INTERLEAVE, dma_cap_mask);
sspi->rx_chan = dma_request_channel(dma_cap_mask, (dma_filter_fn)sirfsoc_dma_filter_id,
(void *)rx_dma_ch);
if (!sspi->rx_chan) {
dev_err(&pdev->dev, "can not allocate rx dma channel\n");
ret = -ENODEV;
goto free_master;
}
sspi->tx_chan = dma_request_channel(dma_cap_mask, (dma_filter_fn)sirfsoc_dma_filter_id,
(void *)tx_dma_ch);
if (!sspi->tx_chan) {
dev_err(&pdev->dev, "can not allocate tx dma channel\n");
ret = -ENODEV;
goto free_rx_dma;
}
sspi->clk = clk_get(&pdev->dev, NULL);
if (IS_ERR(sspi->clk)) {
ret = PTR_ERR(sspi->clk);
goto free_tx_dma;
}
clk_prepare_enable(sspi->clk);
sspi->ctrl_freq = clk_get_rate(sspi->clk);
init_completion(&sspi->rx_done);
init_completion(&sspi->tx_done);
writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
/* We are not using dummy delay between command and data */
writel(0, sspi->base + SIRFSOC_SPI_DUMMY_DELAY_CTL);
sspi->dummypage = kmalloc(2 * PAGE_SIZE, GFP_KERNEL);
if (!sspi->dummypage) {
ret = -ENOMEM;
goto free_clk;
}
ret = spi_bitbang_start(&sspi->bitbang);
if (ret)
goto free_dummypage;
dev_info(&pdev->dev, "registerred, bus number = %d\n", master->bus_num);
return 0;
free_dummypage:
kfree(sspi->dummypage);
free_clk:
clk_disable_unprepare(sspi->clk);
clk_put(sspi->clk);
free_tx_dma:
dma_release_channel(sspi->tx_chan);
free_rx_dma:
dma_release_channel(sspi->rx_chan);
free_master:
spi_master_put(master);
err_cs:
return ret;
}
static int spi_sirfsoc_remove(struct platform_device *pdev)
{
struct spi_master *master;
struct sirfsoc_spi *sspi;
int i;
master = platform_get_drvdata(pdev);
sspi = spi_master_get_devdata(master);
spi_bitbang_stop(&sspi->bitbang);
for (i = 0; i < master->num_chipselect; i++) {
if (sspi->chipselect[i] > 0)
gpio_free(sspi->chipselect[i]);
}
kfree(sspi->dummypage);
clk_disable_unprepare(sspi->clk);
clk_put(sspi->clk);
dma_release_channel(sspi->rx_chan);
dma_release_channel(sspi->tx_chan);
spi_master_put(master);
return 0;
}
#ifdef CONFIG_PM
static int spi_sirfsoc_suspend(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
struct sirfsoc_spi *sspi = spi_master_get_devdata(master);
clk_disable(sspi->clk);
return 0;
}
static int spi_sirfsoc_resume(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
struct sirfsoc_spi *sspi = spi_master_get_devdata(master);
clk_enable(sspi->clk);
writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
return 0;
}
static const struct dev_pm_ops spi_sirfsoc_pm_ops = {
.suspend = spi_sirfsoc_suspend,
.resume = spi_sirfsoc_resume,
};
#endif
static const struct of_device_id spi_sirfsoc_of_match[] = {
{ .compatible = "sirf,prima2-spi", },
{ .compatible = "sirf,marco-spi", },
{}
};
MODULE_DEVICE_TABLE(of, spi_sirfsoc_of_match);
static struct platform_driver spi_sirfsoc_driver = {
.driver = {
.name = DRIVER_NAME,
.owner = THIS_MODULE,
#ifdef CONFIG_PM
.pm = &spi_sirfsoc_pm_ops,
#endif
.of_match_table = spi_sirfsoc_of_match,
},
.probe = spi_sirfsoc_probe,
.remove = spi_sirfsoc_remove,
};
module_platform_driver(spi_sirfsoc_driver);
MODULE_DESCRIPTION("SiRF SoC SPI master driver");
MODULE_AUTHOR("Zhiwu Song <Zhiwu.Song@csr.com>, "
"Barry Song <Baohua.Song@csr.com>");
MODULE_LICENSE("GPL v2");