linux/drivers/spi/spi-sprd.c
Chunyan Zhang 7907cad7d0
spi: sprd: Add missing MODULE_DEVICE_TABLE
MODULE_DEVICE_TABLE is used to extract the device information out of the
driver and builds a table when being compiled. If using this macro,
kernel can find the driver if available when the device is plugged in,
and then loads that driver and initializes the device.

Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Link: https://lore.kernel.org/r/20210512093534.243040-1-zhang.lyra@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-05-12 13:01:43 +01:00

1088 lines
27 KiB
C

// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2018 Spreadtrum Communications Inc.
#include <linux/clk.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/dma/sprd-dma.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_dma.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/spi/spi.h>
#define SPRD_SPI_TXD 0x0
#define SPRD_SPI_CLKD 0x4
#define SPRD_SPI_CTL0 0x8
#define SPRD_SPI_CTL1 0xc
#define SPRD_SPI_CTL2 0x10
#define SPRD_SPI_CTL3 0x14
#define SPRD_SPI_CTL4 0x18
#define SPRD_SPI_CTL5 0x1c
#define SPRD_SPI_INT_EN 0x20
#define SPRD_SPI_INT_CLR 0x24
#define SPRD_SPI_INT_RAW_STS 0x28
#define SPRD_SPI_INT_MASK_STS 0x2c
#define SPRD_SPI_STS1 0x30
#define SPRD_SPI_STS2 0x34
#define SPRD_SPI_DSP_WAIT 0x38
#define SPRD_SPI_STS3 0x3c
#define SPRD_SPI_CTL6 0x40
#define SPRD_SPI_STS4 0x44
#define SPRD_SPI_FIFO_RST 0x48
#define SPRD_SPI_CTL7 0x4c
#define SPRD_SPI_STS5 0x50
#define SPRD_SPI_CTL8 0x54
#define SPRD_SPI_CTL9 0x58
#define SPRD_SPI_CTL10 0x5c
#define SPRD_SPI_CTL11 0x60
#define SPRD_SPI_CTL12 0x64
#define SPRD_SPI_STS6 0x68
#define SPRD_SPI_STS7 0x6c
#define SPRD_SPI_STS8 0x70
#define SPRD_SPI_STS9 0x74
/* Bits & mask definition for register CTL0 */
#define SPRD_SPI_SCK_REV BIT(13)
#define SPRD_SPI_NG_TX BIT(1)
#define SPRD_SPI_NG_RX BIT(0)
#define SPRD_SPI_CHNL_LEN_MASK GENMASK(4, 0)
#define SPRD_SPI_CSN_MASK GENMASK(11, 8)
#define SPRD_SPI_CS0_VALID BIT(8)
/* Bits & mask definition for register SPI_INT_EN */
#define SPRD_SPI_TX_END_INT_EN BIT(8)
#define SPRD_SPI_RX_END_INT_EN BIT(9)
/* Bits & mask definition for register SPI_INT_RAW_STS */
#define SPRD_SPI_TX_END_RAW BIT(8)
#define SPRD_SPI_RX_END_RAW BIT(9)
/* Bits & mask definition for register SPI_INT_CLR */
#define SPRD_SPI_TX_END_CLR BIT(8)
#define SPRD_SPI_RX_END_CLR BIT(9)
/* Bits & mask definition for register INT_MASK_STS */
#define SPRD_SPI_MASK_RX_END BIT(9)
#define SPRD_SPI_MASK_TX_END BIT(8)
/* Bits & mask definition for register STS2 */
#define SPRD_SPI_TX_BUSY BIT(8)
/* Bits & mask definition for register CTL1 */
#define SPRD_SPI_RX_MODE BIT(12)
#define SPRD_SPI_TX_MODE BIT(13)
#define SPRD_SPI_RTX_MD_MASK GENMASK(13, 12)
/* Bits & mask definition for register CTL2 */
#define SPRD_SPI_DMA_EN BIT(6)
/* Bits & mask definition for register CTL4 */
#define SPRD_SPI_START_RX BIT(9)
#define SPRD_SPI_ONLY_RECV_MASK GENMASK(8, 0)
/* Bits & mask definition for register SPI_INT_CLR */
#define SPRD_SPI_RX_END_INT_CLR BIT(9)
#define SPRD_SPI_TX_END_INT_CLR BIT(8)
/* Bits & mask definition for register SPI_INT_RAW */
#define SPRD_SPI_RX_END_IRQ BIT(9)
#define SPRD_SPI_TX_END_IRQ BIT(8)
/* Bits & mask definition for register CTL12 */
#define SPRD_SPI_SW_RX_REQ BIT(0)
#define SPRD_SPI_SW_TX_REQ BIT(1)
/* Bits & mask definition for register CTL7 */
#define SPRD_SPI_DATA_LINE2_EN BIT(15)
#define SPRD_SPI_MODE_MASK GENMASK(5, 3)
#define SPRD_SPI_MODE_OFFSET 3
#define SPRD_SPI_3WIRE_MODE 4
#define SPRD_SPI_4WIRE_MODE 0
/* Bits & mask definition for register CTL8 */
#define SPRD_SPI_TX_MAX_LEN_MASK GENMASK(19, 0)
#define SPRD_SPI_TX_LEN_H_MASK GENMASK(3, 0)
#define SPRD_SPI_TX_LEN_H_OFFSET 16
/* Bits & mask definition for register CTL9 */
#define SPRD_SPI_TX_LEN_L_MASK GENMASK(15, 0)
/* Bits & mask definition for register CTL10 */
#define SPRD_SPI_RX_MAX_LEN_MASK GENMASK(19, 0)
#define SPRD_SPI_RX_LEN_H_MASK GENMASK(3, 0)
#define SPRD_SPI_RX_LEN_H_OFFSET 16
/* Bits & mask definition for register CTL11 */
#define SPRD_SPI_RX_LEN_L_MASK GENMASK(15, 0)
/* Default & maximum word delay cycles */
#define SPRD_SPI_MIN_DELAY_CYCLE 14
#define SPRD_SPI_MAX_DELAY_CYCLE 130
#define SPRD_SPI_FIFO_SIZE 32
#define SPRD_SPI_CHIP_CS_NUM 0x4
#define SPRD_SPI_CHNL_LEN 2
#define SPRD_SPI_DEFAULT_SOURCE 26000000
#define SPRD_SPI_MAX_SPEED_HZ 48000000
#define SPRD_SPI_AUTOSUSPEND_DELAY 100
#define SPRD_SPI_DMA_STEP 8
enum sprd_spi_dma_channel {
SPRD_SPI_RX,
SPRD_SPI_TX,
SPRD_SPI_MAX,
};
struct sprd_spi_dma {
bool enable;
struct dma_chan *dma_chan[SPRD_SPI_MAX];
enum dma_slave_buswidth width;
u32 fragmens_len;
u32 rx_len;
};
struct sprd_spi {
void __iomem *base;
phys_addr_t phy_base;
struct device *dev;
struct clk *clk;
int irq;
u32 src_clk;
u32 hw_mode;
u32 trans_len;
u32 trans_mode;
u32 word_delay;
u32 hw_speed_hz;
u32 len;
int status;
struct sprd_spi_dma dma;
struct completion xfer_completion;
const void *tx_buf;
void *rx_buf;
int (*read_bufs)(struct sprd_spi *ss, u32 len);
int (*write_bufs)(struct sprd_spi *ss, u32 len);
};
static u32 sprd_spi_transfer_max_timeout(struct sprd_spi *ss,
struct spi_transfer *t)
{
/*
* The time spent on transmission of the full FIFO data is the maximum
* SPI transmission time.
*/
u32 size = t->bits_per_word * SPRD_SPI_FIFO_SIZE;
u32 bit_time_us = DIV_ROUND_UP(USEC_PER_SEC, ss->hw_speed_hz);
u32 total_time_us = size * bit_time_us;
/*
* There is an interval between data and the data in our SPI hardware,
* so the total transmission time need add the interval time.
*/
u32 interval_cycle = SPRD_SPI_FIFO_SIZE * ss->word_delay;
u32 interval_time_us = DIV_ROUND_UP(interval_cycle * USEC_PER_SEC,
ss->src_clk);
return total_time_us + interval_time_us;
}
static int sprd_spi_wait_for_tx_end(struct sprd_spi *ss, struct spi_transfer *t)
{
u32 val, us;
int ret;
us = sprd_spi_transfer_max_timeout(ss, t);
ret = readl_relaxed_poll_timeout(ss->base + SPRD_SPI_INT_RAW_STS, val,
val & SPRD_SPI_TX_END_IRQ, 0, us);
if (ret) {
dev_err(ss->dev, "SPI error, spi send timeout!\n");
return ret;
}
ret = readl_relaxed_poll_timeout(ss->base + SPRD_SPI_STS2, val,
!(val & SPRD_SPI_TX_BUSY), 0, us);
if (ret) {
dev_err(ss->dev, "SPI error, spi busy timeout!\n");
return ret;
}
writel_relaxed(SPRD_SPI_TX_END_INT_CLR, ss->base + SPRD_SPI_INT_CLR);
return 0;
}
static int sprd_spi_wait_for_rx_end(struct sprd_spi *ss, struct spi_transfer *t)
{
u32 val, us;
int ret;
us = sprd_spi_transfer_max_timeout(ss, t);
ret = readl_relaxed_poll_timeout(ss->base + SPRD_SPI_INT_RAW_STS, val,
val & SPRD_SPI_RX_END_IRQ, 0, us);
if (ret) {
dev_err(ss->dev, "SPI error, spi rx timeout!\n");
return ret;
}
writel_relaxed(SPRD_SPI_RX_END_INT_CLR, ss->base + SPRD_SPI_INT_CLR);
return 0;
}
static void sprd_spi_tx_req(struct sprd_spi *ss)
{
writel_relaxed(SPRD_SPI_SW_TX_REQ, ss->base + SPRD_SPI_CTL12);
}
static void sprd_spi_rx_req(struct sprd_spi *ss)
{
writel_relaxed(SPRD_SPI_SW_RX_REQ, ss->base + SPRD_SPI_CTL12);
}
static void sprd_spi_enter_idle(struct sprd_spi *ss)
{
u32 val = readl_relaxed(ss->base + SPRD_SPI_CTL1);
val &= ~SPRD_SPI_RTX_MD_MASK;
writel_relaxed(val, ss->base + SPRD_SPI_CTL1);
}
static void sprd_spi_set_transfer_bits(struct sprd_spi *ss, u32 bits)
{
u32 val = readl_relaxed(ss->base + SPRD_SPI_CTL0);
/* Set the valid bits for every transaction */
val &= ~(SPRD_SPI_CHNL_LEN_MASK << SPRD_SPI_CHNL_LEN);
val |= bits << SPRD_SPI_CHNL_LEN;
writel_relaxed(val, ss->base + SPRD_SPI_CTL0);
}
static void sprd_spi_set_tx_length(struct sprd_spi *ss, u32 length)
{
u32 val = readl_relaxed(ss->base + SPRD_SPI_CTL8);
length &= SPRD_SPI_TX_MAX_LEN_MASK;
val &= ~SPRD_SPI_TX_LEN_H_MASK;
val |= length >> SPRD_SPI_TX_LEN_H_OFFSET;
writel_relaxed(val, ss->base + SPRD_SPI_CTL8);
val = length & SPRD_SPI_TX_LEN_L_MASK;
writel_relaxed(val, ss->base + SPRD_SPI_CTL9);
}
static void sprd_spi_set_rx_length(struct sprd_spi *ss, u32 length)
{
u32 val = readl_relaxed(ss->base + SPRD_SPI_CTL10);
length &= SPRD_SPI_RX_MAX_LEN_MASK;
val &= ~SPRD_SPI_RX_LEN_H_MASK;
val |= length >> SPRD_SPI_RX_LEN_H_OFFSET;
writel_relaxed(val, ss->base + SPRD_SPI_CTL10);
val = length & SPRD_SPI_RX_LEN_L_MASK;
writel_relaxed(val, ss->base + SPRD_SPI_CTL11);
}
static void sprd_spi_chipselect(struct spi_device *sdev, bool cs)
{
struct spi_controller *sctlr = sdev->controller;
struct sprd_spi *ss = spi_controller_get_devdata(sctlr);
u32 val;
val = readl_relaxed(ss->base + SPRD_SPI_CTL0);
/* The SPI controller will pull down CS pin if cs is 0 */
if (!cs) {
val &= ~SPRD_SPI_CS0_VALID;
writel_relaxed(val, ss->base + SPRD_SPI_CTL0);
} else {
val |= SPRD_SPI_CSN_MASK;
writel_relaxed(val, ss->base + SPRD_SPI_CTL0);
}
}
static int sprd_spi_write_only_receive(struct sprd_spi *ss, u32 len)
{
u32 val;
/* Clear the start receive bit and reset receive data number */
val = readl_relaxed(ss->base + SPRD_SPI_CTL4);
val &= ~(SPRD_SPI_START_RX | SPRD_SPI_ONLY_RECV_MASK);
writel_relaxed(val, ss->base + SPRD_SPI_CTL4);
/* Set the receive data length */
val = readl_relaxed(ss->base + SPRD_SPI_CTL4);
val |= len & SPRD_SPI_ONLY_RECV_MASK;
writel_relaxed(val, ss->base + SPRD_SPI_CTL4);
/* Trigger to receive data */
val = readl_relaxed(ss->base + SPRD_SPI_CTL4);
val |= SPRD_SPI_START_RX;
writel_relaxed(val, ss->base + SPRD_SPI_CTL4);
return len;
}
static int sprd_spi_write_bufs_u8(struct sprd_spi *ss, u32 len)
{
u8 *tx_p = (u8 *)ss->tx_buf;
int i;
for (i = 0; i < len; i++)
writeb_relaxed(tx_p[i], ss->base + SPRD_SPI_TXD);
ss->tx_buf += i;
return i;
}
static int sprd_spi_write_bufs_u16(struct sprd_spi *ss, u32 len)
{
u16 *tx_p = (u16 *)ss->tx_buf;
int i;
for (i = 0; i < len; i++)
writew_relaxed(tx_p[i], ss->base + SPRD_SPI_TXD);
ss->tx_buf += i << 1;
return i << 1;
}
static int sprd_spi_write_bufs_u32(struct sprd_spi *ss, u32 len)
{
u32 *tx_p = (u32 *)ss->tx_buf;
int i;
for (i = 0; i < len; i++)
writel_relaxed(tx_p[i], ss->base + SPRD_SPI_TXD);
ss->tx_buf += i << 2;
return i << 2;
}
static int sprd_spi_read_bufs_u8(struct sprd_spi *ss, u32 len)
{
u8 *rx_p = (u8 *)ss->rx_buf;
int i;
for (i = 0; i < len; i++)
rx_p[i] = readb_relaxed(ss->base + SPRD_SPI_TXD);
ss->rx_buf += i;
return i;
}
static int sprd_spi_read_bufs_u16(struct sprd_spi *ss, u32 len)
{
u16 *rx_p = (u16 *)ss->rx_buf;
int i;
for (i = 0; i < len; i++)
rx_p[i] = readw_relaxed(ss->base + SPRD_SPI_TXD);
ss->rx_buf += i << 1;
return i << 1;
}
static int sprd_spi_read_bufs_u32(struct sprd_spi *ss, u32 len)
{
u32 *rx_p = (u32 *)ss->rx_buf;
int i;
for (i = 0; i < len; i++)
rx_p[i] = readl_relaxed(ss->base + SPRD_SPI_TXD);
ss->rx_buf += i << 2;
return i << 2;
}
static int sprd_spi_txrx_bufs(struct spi_device *sdev, struct spi_transfer *t)
{
struct sprd_spi *ss = spi_controller_get_devdata(sdev->controller);
u32 trans_len = ss->trans_len, len;
int ret, write_size = 0, read_size = 0;
while (trans_len) {
len = trans_len > SPRD_SPI_FIFO_SIZE ? SPRD_SPI_FIFO_SIZE :
trans_len;
if (ss->trans_mode & SPRD_SPI_TX_MODE) {
sprd_spi_set_tx_length(ss, len);
write_size += ss->write_bufs(ss, len);
/*
* For our 3 wires mode or dual TX line mode, we need
* to request the controller to transfer.
*/
if (ss->hw_mode & SPI_3WIRE || ss->hw_mode & SPI_TX_DUAL)
sprd_spi_tx_req(ss);
ret = sprd_spi_wait_for_tx_end(ss, t);
} else {
sprd_spi_set_rx_length(ss, len);
/*
* For our 3 wires mode or dual TX line mode, we need
* to request the controller to read.
*/
if (ss->hw_mode & SPI_3WIRE || ss->hw_mode & SPI_TX_DUAL)
sprd_spi_rx_req(ss);
else
write_size += ss->write_bufs(ss, len);
ret = sprd_spi_wait_for_rx_end(ss, t);
}
if (ret)
goto complete;
if (ss->trans_mode & SPRD_SPI_RX_MODE)
read_size += ss->read_bufs(ss, len);
trans_len -= len;
}
if (ss->trans_mode & SPRD_SPI_TX_MODE)
ret = write_size;
else
ret = read_size;
complete:
sprd_spi_enter_idle(ss);
return ret;
}
static void sprd_spi_irq_enable(struct sprd_spi *ss)
{
u32 val;
/* Clear interrupt status before enabling interrupt. */
writel_relaxed(SPRD_SPI_TX_END_CLR | SPRD_SPI_RX_END_CLR,
ss->base + SPRD_SPI_INT_CLR);
/* Enable SPI interrupt only in DMA mode. */
val = readl_relaxed(ss->base + SPRD_SPI_INT_EN);
writel_relaxed(val | SPRD_SPI_TX_END_INT_EN |
SPRD_SPI_RX_END_INT_EN,
ss->base + SPRD_SPI_INT_EN);
}
static void sprd_spi_irq_disable(struct sprd_spi *ss)
{
writel_relaxed(0, ss->base + SPRD_SPI_INT_EN);
}
static void sprd_spi_dma_enable(struct sprd_spi *ss, bool enable)
{
u32 val = readl_relaxed(ss->base + SPRD_SPI_CTL2);
if (enable)
val |= SPRD_SPI_DMA_EN;
else
val &= ~SPRD_SPI_DMA_EN;
writel_relaxed(val, ss->base + SPRD_SPI_CTL2);
}
static int sprd_spi_dma_submit(struct dma_chan *dma_chan,
struct dma_slave_config *c,
struct sg_table *sg,
enum dma_transfer_direction dir)
{
struct dma_async_tx_descriptor *desc;
dma_cookie_t cookie;
unsigned long flags;
int ret;
ret = dmaengine_slave_config(dma_chan, c);
if (ret < 0)
return ret;
flags = SPRD_DMA_FLAGS(SPRD_DMA_CHN_MODE_NONE, SPRD_DMA_NO_TRG,
SPRD_DMA_FRAG_REQ, SPRD_DMA_TRANS_INT);
desc = dmaengine_prep_slave_sg(dma_chan, sg->sgl, sg->nents, dir, flags);
if (!desc)
return -ENODEV;
cookie = dmaengine_submit(desc);
if (dma_submit_error(cookie))
return dma_submit_error(cookie);
dma_async_issue_pending(dma_chan);
return 0;
}
static int sprd_spi_dma_rx_config(struct sprd_spi *ss, struct spi_transfer *t)
{
struct dma_chan *dma_chan = ss->dma.dma_chan[SPRD_SPI_RX];
struct dma_slave_config config = {
.src_addr = ss->phy_base,
.src_addr_width = ss->dma.width,
.dst_addr_width = ss->dma.width,
.dst_maxburst = ss->dma.fragmens_len,
};
int ret;
ret = sprd_spi_dma_submit(dma_chan, &config, &t->rx_sg, DMA_DEV_TO_MEM);
if (ret)
return ret;
return ss->dma.rx_len;
}
static int sprd_spi_dma_tx_config(struct sprd_spi *ss, struct spi_transfer *t)
{
struct dma_chan *dma_chan = ss->dma.dma_chan[SPRD_SPI_TX];
struct dma_slave_config config = {
.dst_addr = ss->phy_base,
.src_addr_width = ss->dma.width,
.dst_addr_width = ss->dma.width,
.src_maxburst = ss->dma.fragmens_len,
};
int ret;
ret = sprd_spi_dma_submit(dma_chan, &config, &t->tx_sg, DMA_MEM_TO_DEV);
if (ret)
return ret;
return t->len;
}
static int sprd_spi_dma_request(struct sprd_spi *ss)
{
ss->dma.dma_chan[SPRD_SPI_RX] = dma_request_chan(ss->dev, "rx_chn");
if (IS_ERR_OR_NULL(ss->dma.dma_chan[SPRD_SPI_RX]))
return dev_err_probe(ss->dev, PTR_ERR(ss->dma.dma_chan[SPRD_SPI_RX]),
"request RX DMA channel failed!\n");
ss->dma.dma_chan[SPRD_SPI_TX] = dma_request_chan(ss->dev, "tx_chn");
if (IS_ERR_OR_NULL(ss->dma.dma_chan[SPRD_SPI_TX])) {
dma_release_channel(ss->dma.dma_chan[SPRD_SPI_RX]);
return dev_err_probe(ss->dev, PTR_ERR(ss->dma.dma_chan[SPRD_SPI_TX]),
"request TX DMA channel failed!\n");
}
return 0;
}
static void sprd_spi_dma_release(struct sprd_spi *ss)
{
if (ss->dma.dma_chan[SPRD_SPI_RX])
dma_release_channel(ss->dma.dma_chan[SPRD_SPI_RX]);
if (ss->dma.dma_chan[SPRD_SPI_TX])
dma_release_channel(ss->dma.dma_chan[SPRD_SPI_TX]);
}
static int sprd_spi_dma_txrx_bufs(struct spi_device *sdev,
struct spi_transfer *t)
{
struct sprd_spi *ss = spi_master_get_devdata(sdev->master);
u32 trans_len = ss->trans_len;
int ret, write_size = 0;
reinit_completion(&ss->xfer_completion);
sprd_spi_irq_enable(ss);
if (ss->trans_mode & SPRD_SPI_TX_MODE) {
write_size = sprd_spi_dma_tx_config(ss, t);
sprd_spi_set_tx_length(ss, trans_len);
/*
* For our 3 wires mode or dual TX line mode, we need
* to request the controller to transfer.
*/
if (ss->hw_mode & SPI_3WIRE || ss->hw_mode & SPI_TX_DUAL)
sprd_spi_tx_req(ss);
} else {
sprd_spi_set_rx_length(ss, trans_len);
/*
* For our 3 wires mode or dual TX line mode, we need
* to request the controller to read.
*/
if (ss->hw_mode & SPI_3WIRE || ss->hw_mode & SPI_TX_DUAL)
sprd_spi_rx_req(ss);
else
write_size = ss->write_bufs(ss, trans_len);
}
if (write_size < 0) {
ret = write_size;
dev_err(ss->dev, "failed to write, ret = %d\n", ret);
goto trans_complete;
}
if (ss->trans_mode & SPRD_SPI_RX_MODE) {
/*
* Set up the DMA receive data length, which must be an
* integral multiple of fragment length. But when the length
* of received data is less than fragment length, DMA can be
* configured to receive data according to the actual length
* of received data.
*/
ss->dma.rx_len = t->len > ss->dma.fragmens_len ?
(t->len - t->len % ss->dma.fragmens_len) :
t->len;
ret = sprd_spi_dma_rx_config(ss, t);
if (ret < 0) {
dev_err(&sdev->dev,
"failed to configure rx DMA, ret = %d\n", ret);
goto trans_complete;
}
}
sprd_spi_dma_enable(ss, true);
wait_for_completion(&(ss->xfer_completion));
if (ss->trans_mode & SPRD_SPI_TX_MODE)
ret = write_size;
else
ret = ss->dma.rx_len;
trans_complete:
sprd_spi_dma_enable(ss, false);
sprd_spi_enter_idle(ss);
sprd_spi_irq_disable(ss);
return ret;
}
static void sprd_spi_set_speed(struct sprd_spi *ss, u32 speed_hz)
{
/*
* From SPI datasheet, the prescale calculation formula:
* prescale = SPI source clock / (2 * SPI_freq) - 1;
*/
u32 clk_div = DIV_ROUND_UP(ss->src_clk, speed_hz << 1) - 1;
/* Save the real hardware speed */
ss->hw_speed_hz = (ss->src_clk >> 1) / (clk_div + 1);
writel_relaxed(clk_div, ss->base + SPRD_SPI_CLKD);
}
static int sprd_spi_init_hw(struct sprd_spi *ss, struct spi_transfer *t)
{
struct spi_delay *d = &t->word_delay;
u16 word_delay, interval;
u32 val;
if (d->unit != SPI_DELAY_UNIT_SCK)
return -EINVAL;
val = readl_relaxed(ss->base + SPRD_SPI_CTL0);
val &= ~(SPRD_SPI_SCK_REV | SPRD_SPI_NG_TX | SPRD_SPI_NG_RX);
/* Set default chip selection, clock phase and clock polarity */
val |= ss->hw_mode & SPI_CPHA ? SPRD_SPI_NG_RX : SPRD_SPI_NG_TX;
val |= ss->hw_mode & SPI_CPOL ? SPRD_SPI_SCK_REV : 0;
writel_relaxed(val, ss->base + SPRD_SPI_CTL0);
/*
* Set the intervals of two SPI frames, and the inteval calculation
* formula as below per datasheet:
* interval time (source clock cycles) = interval * 4 + 10.
*/
word_delay = clamp_t(u16, d->value, SPRD_SPI_MIN_DELAY_CYCLE,
SPRD_SPI_MAX_DELAY_CYCLE);
interval = DIV_ROUND_UP(word_delay - 10, 4);
ss->word_delay = interval * 4 + 10;
writel_relaxed(interval, ss->base + SPRD_SPI_CTL5);
/* Reset SPI fifo */
writel_relaxed(1, ss->base + SPRD_SPI_FIFO_RST);
writel_relaxed(0, ss->base + SPRD_SPI_FIFO_RST);
/* Set SPI work mode */
val = readl_relaxed(ss->base + SPRD_SPI_CTL7);
val &= ~SPRD_SPI_MODE_MASK;
if (ss->hw_mode & SPI_3WIRE)
val |= SPRD_SPI_3WIRE_MODE << SPRD_SPI_MODE_OFFSET;
else
val |= SPRD_SPI_4WIRE_MODE << SPRD_SPI_MODE_OFFSET;
if (ss->hw_mode & SPI_TX_DUAL)
val |= SPRD_SPI_DATA_LINE2_EN;
else
val &= ~SPRD_SPI_DATA_LINE2_EN;
writel_relaxed(val, ss->base + SPRD_SPI_CTL7);
return 0;
}
static int sprd_spi_setup_transfer(struct spi_device *sdev,
struct spi_transfer *t)
{
struct sprd_spi *ss = spi_controller_get_devdata(sdev->controller);
u8 bits_per_word = t->bits_per_word;
u32 val, mode = 0;
int ret;
ss->len = t->len;
ss->tx_buf = t->tx_buf;
ss->rx_buf = t->rx_buf;
ss->hw_mode = sdev->mode;
ret = sprd_spi_init_hw(ss, t);
if (ret)
return ret;
/* Set tansfer speed and valid bits */
sprd_spi_set_speed(ss, t->speed_hz);
sprd_spi_set_transfer_bits(ss, bits_per_word);
if (bits_per_word > 16)
bits_per_word = round_up(bits_per_word, 16);
else
bits_per_word = round_up(bits_per_word, 8);
switch (bits_per_word) {
case 8:
ss->trans_len = t->len;
ss->read_bufs = sprd_spi_read_bufs_u8;
ss->write_bufs = sprd_spi_write_bufs_u8;
ss->dma.width = DMA_SLAVE_BUSWIDTH_1_BYTE;
ss->dma.fragmens_len = SPRD_SPI_DMA_STEP;
break;
case 16:
ss->trans_len = t->len >> 1;
ss->read_bufs = sprd_spi_read_bufs_u16;
ss->write_bufs = sprd_spi_write_bufs_u16;
ss->dma.width = DMA_SLAVE_BUSWIDTH_2_BYTES;
ss->dma.fragmens_len = SPRD_SPI_DMA_STEP << 1;
break;
case 32:
ss->trans_len = t->len >> 2;
ss->read_bufs = sprd_spi_read_bufs_u32;
ss->write_bufs = sprd_spi_write_bufs_u32;
ss->dma.width = DMA_SLAVE_BUSWIDTH_4_BYTES;
ss->dma.fragmens_len = SPRD_SPI_DMA_STEP << 2;
break;
default:
return -EINVAL;
}
/* Set transfer read or write mode */
val = readl_relaxed(ss->base + SPRD_SPI_CTL1);
val &= ~SPRD_SPI_RTX_MD_MASK;
if (t->tx_buf)
mode |= SPRD_SPI_TX_MODE;
if (t->rx_buf)
mode |= SPRD_SPI_RX_MODE;
writel_relaxed(val | mode, ss->base + SPRD_SPI_CTL1);
ss->trans_mode = mode;
/*
* If in only receive mode, we need to trigger the SPI controller to
* receive data automatically.
*/
if (ss->trans_mode == SPRD_SPI_RX_MODE)
ss->write_bufs = sprd_spi_write_only_receive;
return 0;
}
static int sprd_spi_transfer_one(struct spi_controller *sctlr,
struct spi_device *sdev,
struct spi_transfer *t)
{
int ret;
ret = sprd_spi_setup_transfer(sdev, t);
if (ret)
goto setup_err;
if (sctlr->can_dma(sctlr, sdev, t))
ret = sprd_spi_dma_txrx_bufs(sdev, t);
else
ret = sprd_spi_txrx_bufs(sdev, t);
if (ret == t->len)
ret = 0;
else if (ret >= 0)
ret = -EREMOTEIO;
setup_err:
spi_finalize_current_transfer(sctlr);
return ret;
}
static irqreturn_t sprd_spi_handle_irq(int irq, void *data)
{
struct sprd_spi *ss = (struct sprd_spi *)data;
u32 val = readl_relaxed(ss->base + SPRD_SPI_INT_MASK_STS);
if (val & SPRD_SPI_MASK_TX_END) {
writel_relaxed(SPRD_SPI_TX_END_CLR, ss->base + SPRD_SPI_INT_CLR);
if (!(ss->trans_mode & SPRD_SPI_RX_MODE))
complete(&ss->xfer_completion);
return IRQ_HANDLED;
}
if (val & SPRD_SPI_MASK_RX_END) {
writel_relaxed(SPRD_SPI_RX_END_CLR, ss->base + SPRD_SPI_INT_CLR);
if (ss->dma.rx_len < ss->len) {
ss->rx_buf += ss->dma.rx_len;
ss->dma.rx_len +=
ss->read_bufs(ss, ss->len - ss->dma.rx_len);
}
complete(&ss->xfer_completion);
return IRQ_HANDLED;
}
return IRQ_NONE;
}
static int sprd_spi_irq_init(struct platform_device *pdev, struct sprd_spi *ss)
{
int ret;
ss->irq = platform_get_irq(pdev, 0);
if (ss->irq < 0)
return ss->irq;
ret = devm_request_irq(&pdev->dev, ss->irq, sprd_spi_handle_irq,
0, pdev->name, ss);
if (ret)
dev_err(&pdev->dev, "failed to request spi irq %d, ret = %d\n",
ss->irq, ret);
return ret;
}
static int sprd_spi_clk_init(struct platform_device *pdev, struct sprd_spi *ss)
{
struct clk *clk_spi, *clk_parent;
clk_spi = devm_clk_get(&pdev->dev, "spi");
if (IS_ERR(clk_spi)) {
dev_warn(&pdev->dev, "can't get the spi clock\n");
clk_spi = NULL;
}
clk_parent = devm_clk_get(&pdev->dev, "source");
if (IS_ERR(clk_parent)) {
dev_warn(&pdev->dev, "can't get the source clock\n");
clk_parent = NULL;
}
ss->clk = devm_clk_get(&pdev->dev, "enable");
if (IS_ERR(ss->clk)) {
dev_err(&pdev->dev, "can't get the enable clock\n");
return PTR_ERR(ss->clk);
}
if (!clk_set_parent(clk_spi, clk_parent))
ss->src_clk = clk_get_rate(clk_spi);
else
ss->src_clk = SPRD_SPI_DEFAULT_SOURCE;
return 0;
}
static bool sprd_spi_can_dma(struct spi_controller *sctlr,
struct spi_device *spi, struct spi_transfer *t)
{
struct sprd_spi *ss = spi_controller_get_devdata(sctlr);
return ss->dma.enable && (t->len > SPRD_SPI_FIFO_SIZE);
}
static int sprd_spi_dma_init(struct platform_device *pdev, struct sprd_spi *ss)
{
int ret;
ret = sprd_spi_dma_request(ss);
if (ret) {
if (ret == -EPROBE_DEFER)
return ret;
dev_warn(&pdev->dev,
"failed to request dma, enter no dma mode, ret = %d\n",
ret);
return 0;
}
ss->dma.enable = true;
return 0;
}
static int sprd_spi_probe(struct platform_device *pdev)
{
struct spi_controller *sctlr;
struct resource *res;
struct sprd_spi *ss;
int ret;
pdev->id = of_alias_get_id(pdev->dev.of_node, "spi");
sctlr = spi_alloc_master(&pdev->dev, sizeof(*ss));
if (!sctlr)
return -ENOMEM;
ss = spi_controller_get_devdata(sctlr);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
ss->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(ss->base)) {
ret = PTR_ERR(ss->base);
goto free_controller;
}
ss->phy_base = res->start;
ss->dev = &pdev->dev;
sctlr->dev.of_node = pdev->dev.of_node;
sctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_3WIRE | SPI_TX_DUAL;
sctlr->bus_num = pdev->id;
sctlr->set_cs = sprd_spi_chipselect;
sctlr->transfer_one = sprd_spi_transfer_one;
sctlr->can_dma = sprd_spi_can_dma;
sctlr->auto_runtime_pm = true;
sctlr->max_speed_hz = min_t(u32, ss->src_clk >> 1,
SPRD_SPI_MAX_SPEED_HZ);
init_completion(&ss->xfer_completion);
platform_set_drvdata(pdev, sctlr);
ret = sprd_spi_clk_init(pdev, ss);
if (ret)
goto free_controller;
ret = sprd_spi_irq_init(pdev, ss);
if (ret)
goto free_controller;
ret = sprd_spi_dma_init(pdev, ss);
if (ret)
goto free_controller;
ret = clk_prepare_enable(ss->clk);
if (ret)
goto release_dma;
ret = pm_runtime_set_active(&pdev->dev);
if (ret < 0)
goto disable_clk;
pm_runtime_set_autosuspend_delay(&pdev->dev,
SPRD_SPI_AUTOSUSPEND_DELAY);
pm_runtime_use_autosuspend(&pdev->dev);
pm_runtime_enable(&pdev->dev);
ret = pm_runtime_get_sync(&pdev->dev);
if (ret < 0) {
dev_err(&pdev->dev, "failed to resume SPI controller\n");
goto err_rpm_put;
}
ret = devm_spi_register_controller(&pdev->dev, sctlr);
if (ret)
goto err_rpm_put;
pm_runtime_mark_last_busy(&pdev->dev);
pm_runtime_put_autosuspend(&pdev->dev);
return 0;
err_rpm_put:
pm_runtime_put_noidle(&pdev->dev);
pm_runtime_disable(&pdev->dev);
disable_clk:
clk_disable_unprepare(ss->clk);
release_dma:
sprd_spi_dma_release(ss);
free_controller:
spi_controller_put(sctlr);
return ret;
}
static int sprd_spi_remove(struct platform_device *pdev)
{
struct spi_controller *sctlr = platform_get_drvdata(pdev);
struct sprd_spi *ss = spi_controller_get_devdata(sctlr);
int ret;
ret = pm_runtime_get_sync(ss->dev);
if (ret < 0) {
pm_runtime_put_noidle(ss->dev);
dev_err(ss->dev, "failed to resume SPI controller\n");
return ret;
}
spi_controller_suspend(sctlr);
if (ss->dma.enable)
sprd_spi_dma_release(ss);
clk_disable_unprepare(ss->clk);
pm_runtime_put_noidle(&pdev->dev);
pm_runtime_disable(&pdev->dev);
return 0;
}
static int __maybe_unused sprd_spi_runtime_suspend(struct device *dev)
{
struct spi_controller *sctlr = dev_get_drvdata(dev);
struct sprd_spi *ss = spi_controller_get_devdata(sctlr);
if (ss->dma.enable)
sprd_spi_dma_release(ss);
clk_disable_unprepare(ss->clk);
return 0;
}
static int __maybe_unused sprd_spi_runtime_resume(struct device *dev)
{
struct spi_controller *sctlr = dev_get_drvdata(dev);
struct sprd_spi *ss = spi_controller_get_devdata(sctlr);
int ret;
ret = clk_prepare_enable(ss->clk);
if (ret)
return ret;
if (!ss->dma.enable)
return 0;
ret = sprd_spi_dma_request(ss);
if (ret)
clk_disable_unprepare(ss->clk);
return ret;
}
static const struct dev_pm_ops sprd_spi_pm_ops = {
SET_RUNTIME_PM_OPS(sprd_spi_runtime_suspend,
sprd_spi_runtime_resume, NULL)
};
static const struct of_device_id sprd_spi_of_match[] = {
{ .compatible = "sprd,sc9860-spi", },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, sprd_spi_of_match);
static struct platform_driver sprd_spi_driver = {
.driver = {
.name = "sprd-spi",
.of_match_table = sprd_spi_of_match,
.pm = &sprd_spi_pm_ops,
},
.probe = sprd_spi_probe,
.remove = sprd_spi_remove,
};
module_platform_driver(sprd_spi_driver);
MODULE_DESCRIPTION("Spreadtrum SPI Controller driver");
MODULE_AUTHOR("Lanqing Liu <lanqing.liu@spreadtrum.com>");
MODULE_LICENSE("GPL v2");