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// SPDX-License-Identifier: GPL-2.0+
// Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
// Copyright (C) 2008 Juergen Beisert
#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/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>
#include <linux/types.h>
#include <linux/of.h>
#include <linux/property.h>
#include <linux/dma/imx-dma.h>
#define DRIVER_NAME "spi_imx"
static bool use_dma = true;
module_param(use_dma, bool, 0644);
MODULE_PARM_DESC(use_dma, "Enable usage of DMA when available (default)");
/* define polling limits */
static unsigned int polling_limit_us = 30;
module_param(polling_limit_us, uint, 0664);
MODULE_PARM_DESC(polling_limit_us,
"time in us to run a transfer in polling mode\n");
#define MXC_RPM_TIMEOUT 2000 /* 2000ms */
#define MXC_CSPIRXDATA 0x00
#define MXC_CSPITXDATA 0x04
#define MXC_CSPICTRL 0x08
#define MXC_CSPIINT 0x0c
#define MXC_RESET 0x1c
/* generic defines to abstract from the different register layouts */
#define MXC_INT_RR (1 << 0) /* Receive data ready interrupt */
#define MXC_INT_TE (1 << 1) /* Transmit FIFO empty interrupt */
#define MXC_INT_RDR BIT(4) /* Receive date threshold interrupt */
/* The maximum bytes that a sdma BD can transfer. */
#define MAX_SDMA_BD_BYTES (1 << 15)
#define MX51_ECSPI_CTRL_MAX_BURST 512
/* The maximum bytes that IMX53_ECSPI can transfer in target mode.*/
#define MX53_MAX_TRANSFER_BYTES 512
enum spi_imx_devtype {
IMX1_CSPI,
IMX21_CSPI,
IMX27_CSPI,
IMX31_CSPI,
IMX35_CSPI, /* CSPI on all i.mx except above */
IMX51_ECSPI, /* ECSPI on i.mx51 */
IMX53_ECSPI, /* ECSPI on i.mx53 and later */
};
struct spi_imx_data;
struct spi_imx_devtype_data {
void (*intctrl)(struct spi_imx_data *spi_imx, int enable);
int (*prepare_message)(struct spi_imx_data *spi_imx, struct spi_message *msg);
int (*prepare_transfer)(struct spi_imx_data *spi_imx, struct spi_device *spi);
void (*trigger)(struct spi_imx_data *spi_imx);
int (*rx_available)(struct spi_imx_data *spi_imx);
void (*reset)(struct spi_imx_data *spi_imx);
void (*setup_wml)(struct spi_imx_data *spi_imx);
void (*disable)(struct spi_imx_data *spi_imx);
bool has_dmamode;
bool has_targetmode;
unsigned int fifo_size;
bool dynamic_burst;
/*
* ERR009165 fixed or not:
* https://www.nxp.com/docs/en/errata/IMX6DQCE.pdf
*/
bool tx_glitch_fixed;
enum spi_imx_devtype devtype;
};
struct spi_imx_data {
struct spi_controller *controller;
struct device *dev;
struct completion xfer_done;
void __iomem *base;
unsigned long base_phys;
struct clk *clk_per;
struct clk *clk_ipg;
unsigned long spi_clk;
unsigned int spi_bus_clk;
unsigned int bits_per_word;
unsigned int spi_drctl;
unsigned int count, remainder;
void (*tx)(struct spi_imx_data *spi_imx);
void (*rx)(struct spi_imx_data *spi_imx);
void *rx_buf;
const void *tx_buf;
unsigned int txfifo; /* number of words pushed in tx FIFO */
unsigned int dynamic_burst;
bool rx_only;
/* Target mode */
bool target_mode;
bool target_aborted;
unsigned int target_burst;
/* DMA */
bool usedma;
u32 wml;
struct completion dma_rx_completion;
struct completion dma_tx_completion;
const struct spi_imx_devtype_data *devtype_data;
};
static inline int is_imx27_cspi(struct spi_imx_data *d)
{
return d->devtype_data->devtype == IMX27_CSPI;
}
static inline int is_imx35_cspi(struct spi_imx_data *d)
{
return d->devtype_data->devtype == IMX35_CSPI;
}
static inline int is_imx51_ecspi(struct spi_imx_data *d)
{
return d->devtype_data->devtype == IMX51_ECSPI;
}
static inline int is_imx53_ecspi(struct spi_imx_data *d)
{
return d->devtype_data->devtype == IMX53_ECSPI;
}
#define MXC_SPI_BUF_RX(type) \
static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx) \
{ \
unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA); \
\
if (spi_imx->rx_buf) { \
*(type *)spi_imx->rx_buf = val; \
spi_imx->rx_buf += sizeof(type); \
} \
\
spi_imx->remainder -= sizeof(type); \
}
#define MXC_SPI_BUF_TX(type) \
static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx) \
{ \
type val = 0; \
\
if (spi_imx->tx_buf) { \
val = *(type *)spi_imx->tx_buf; \
spi_imx->tx_buf += sizeof(type); \
} \
\
spi_imx->count -= sizeof(type); \
\
writel(val, spi_imx->base + MXC_CSPITXDATA); \
}
MXC_SPI_BUF_RX(u8)
MXC_SPI_BUF_TX(u8)
MXC_SPI_BUF_RX(u16)
MXC_SPI_BUF_TX(u16)
MXC_SPI_BUF_RX(u32)
MXC_SPI_BUF_TX(u32)
/* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
* (which is currently not the case in this driver)
*/
static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
256, 384, 512, 768, 1024};
/* MX21, MX27 */
static unsigned int spi_imx_clkdiv_1(unsigned int fin,
unsigned int fspi, unsigned int max, unsigned int *fres)
{
int i;
for (i = 2; i < max; i++)
if (fspi * mxc_clkdivs[i] >= fin)
break;
*fres = fin / mxc_clkdivs[i];
return i;
}
/* MX1, MX31, MX35, MX51 CSPI */
static unsigned int spi_imx_clkdiv_2(unsigned int fin,
unsigned int fspi, unsigned int *fres)
{
int i, div = 4;
for (i = 0; i < 7; i++) {
if (fspi * div >= fin)
goto out;
div <<= 1;
}
out:
*fres = fin / div;
return i;
}
static int spi_imx_bytes_per_word(const int bits_per_word)
{
if (bits_per_word <= 8)
return 1;
else if (bits_per_word <= 16)
return 2;
else
return 4;
}
static bool spi_imx_can_dma(struct spi_controller *controller, struct spi_device *spi,
struct spi_transfer *transfer)
{
struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
if (!use_dma || controller->fallback)
return false;
if (!controller->dma_rx)
return false;
if (spi_imx->target_mode)
return false;
if (transfer->len < spi_imx->devtype_data->fifo_size)
return false;
spi_imx->dynamic_burst = 0;
return true;
}
/*
* Note the number of natively supported chip selects for MX51 is 4. Some
* devices may have less actual SS pins but the register map supports 4. When
* using gpio chip selects the cs values passed into the macros below can go
* outside the range 0 - 3. We therefore need to limit the cs value to avoid
* corrupting bits outside the allocated locations.
*
* The simplest way to do this is to just mask the cs bits to 2 bits. This
* still allows all 4 native chip selects to work as well as gpio chip selects
* (which can use any of the 4 chip select configurations).
*/
#define MX51_ECSPI_CTRL 0x08
#define MX51_ECSPI_CTRL_ENABLE (1 << 0)
#define MX51_ECSPI_CTRL_XCH (1 << 2)
#define MX51_ECSPI_CTRL_SMC (1 << 3)
#define MX51_ECSPI_CTRL_MODE_MASK (0xf << 4)
#define MX51_ECSPI_CTRL_DRCTL(drctl) ((drctl) << 16)
#define MX51_ECSPI_CTRL_POSTDIV_OFFSET 8
#define MX51_ECSPI_CTRL_PREDIV_OFFSET 12
#define MX51_ECSPI_CTRL_CS(cs) ((cs & 3) << 18)
#define MX51_ECSPI_CTRL_BL_OFFSET 20
#define MX51_ECSPI_CTRL_BL_MASK (0xfff << 20)
#define MX51_ECSPI_CONFIG 0x0c
#define MX51_ECSPI_CONFIG_SCLKPHA(cs) (1 << ((cs & 3) + 0))
#define MX51_ECSPI_CONFIG_SCLKPOL(cs) (1 << ((cs & 3) + 4))
#define MX51_ECSPI_CONFIG_SBBCTRL(cs) (1 << ((cs & 3) + 8))
#define MX51_ECSPI_CONFIG_SSBPOL(cs) (1 << ((cs & 3) + 12))
#define MX51_ECSPI_CONFIG_DATACTL(cs) (1 << ((cs & 3) + 16))
#define MX51_ECSPI_CONFIG_SCLKCTL(cs) (1 << ((cs & 3) + 20))
#define MX51_ECSPI_INT 0x10
#define MX51_ECSPI_INT_TEEN (1 << 0)
#define MX51_ECSPI_INT_RREN (1 << 3)
#define MX51_ECSPI_INT_RDREN (1 << 4)
#define MX51_ECSPI_DMA 0x14
#define MX51_ECSPI_DMA_TX_WML(wml) ((wml) & 0x3f)
#define MX51_ECSPI_DMA_RX_WML(wml) (((wml) & 0x3f) << 16)
#define MX51_ECSPI_DMA_RXT_WML(wml) (((wml) & 0x3f) << 24)
#define MX51_ECSPI_DMA_TEDEN (1 << 7)
#define MX51_ECSPI_DMA_RXDEN (1 << 23)
#define MX51_ECSPI_DMA_RXTDEN (1 << 31)
#define MX51_ECSPI_STAT 0x18
#define MX51_ECSPI_STAT_RR (1 << 3)
#define MX51_ECSPI_TESTREG 0x20
#define MX51_ECSPI_TESTREG_LBC BIT(31)
static void spi_imx_buf_rx_swap_u32(struct spi_imx_data *spi_imx)
{
unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);
if (spi_imx->rx_buf) {
#ifdef __LITTLE_ENDIAN
unsigned int bytes_per_word;
bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
if (bytes_per_word == 1)
swab32s(&val);
else if (bytes_per_word == 2)
swahw32s(&val);
#endif
*(u32 *)spi_imx->rx_buf = val;
spi_imx->rx_buf += sizeof(u32);
}
spi_imx->remainder -= sizeof(u32);
}
static void spi_imx_buf_rx_swap(struct spi_imx_data *spi_imx)
{
int unaligned;
u32 val;
unaligned = spi_imx->remainder % 4;
if (!unaligned) {
spi_imx_buf_rx_swap_u32(spi_imx);
return;
}
if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
spi_imx_buf_rx_u16(spi_imx);
return;
}
val = readl(spi_imx->base + MXC_CSPIRXDATA);
while (unaligned--) {
if (spi_imx->rx_buf) {
*(u8 *)spi_imx->rx_buf = (val >> (8 * unaligned)) & 0xff;
spi_imx->rx_buf++;
}
spi_imx->remainder--;
}
}
static void spi_imx_buf_tx_swap_u32(struct spi_imx_data *spi_imx)
{
u32 val = 0;
#ifdef __LITTLE_ENDIAN
unsigned int bytes_per_word;
#endif
if (spi_imx->tx_buf) {
val = *(u32 *)spi_imx->tx_buf;
spi_imx->tx_buf += sizeof(u32);
}
spi_imx->count -= sizeof(u32);
#ifdef __LITTLE_ENDIAN
bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
if (bytes_per_word == 1)
swab32s(&val);
else if (bytes_per_word == 2)
swahw32s(&val);
#endif
writel(val, spi_imx->base + MXC_CSPITXDATA);
}
static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
{
int unaligned;
u32 val = 0;
unaligned = spi_imx->count % 4;
if (!unaligned) {
spi_imx_buf_tx_swap_u32(spi_imx);
return;
}
if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
spi_imx_buf_tx_u16(spi_imx);
return;
}
while (unaligned--) {
if (spi_imx->tx_buf) {
val |= *(u8 *)spi_imx->tx_buf << (8 * unaligned);
spi_imx->tx_buf++;
}
spi_imx->count--;
}
writel(val, spi_imx->base + MXC_CSPITXDATA);
}
static void mx53_ecspi_rx_target(struct spi_imx_data *spi_imx)
{
u32 val = be32_to_cpu(readl(spi_imx->base + MXC_CSPIRXDATA));
if (spi_imx->rx_buf) {
int n_bytes = spi_imx->target_burst % sizeof(val);
if (!n_bytes)
n_bytes = sizeof(val);
memcpy(spi_imx->rx_buf,
((u8 *)&val) + sizeof(val) - n_bytes, n_bytes);
spi_imx->rx_buf += n_bytes;
spi_imx->target_burst -= n_bytes;
}
spi_imx->remainder -= sizeof(u32);
}
static void mx53_ecspi_tx_target(struct spi_imx_data *spi_imx)
{
u32 val = 0;
int n_bytes = spi_imx->count % sizeof(val);
if (!n_bytes)
n_bytes = sizeof(val);
if (spi_imx->tx_buf) {
memcpy(((u8 *)&val) + sizeof(val) - n_bytes,
spi_imx->tx_buf, n_bytes);
val = cpu_to_be32(val);
spi_imx->tx_buf += n_bytes;
}
spi_imx->count -= n_bytes;
writel(val, spi_imx->base + MXC_CSPITXDATA);
}
/* MX51 eCSPI */
static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
unsigned int fspi, unsigned int *fres)
{
/*
* there are two 4-bit dividers, the pre-divider divides by
* $pre, the post-divider by 2^$post
*/
unsigned int pre, post;
unsigned int fin = spi_imx->spi_clk;
fspi = min(fspi, fin);
post = fls(fin) - fls(fspi);
if (fin > fspi << post)
post++;
/* now we have: (fin <= fspi << post) with post being minimal */
post = max(4U, post) - 4;
if (unlikely(post > 0xf)) {
dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
fspi, fin);
return 0xff;
}
pre = DIV_ROUND_UP(fin, fspi << post) - 1;
dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
__func__, fin, fspi, post, pre);
/* Resulting frequency for the SCLK line. */
*fres = (fin / (pre + 1)) >> post;
return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
}
static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
{
unsigned int val = 0;
if (enable & MXC_INT_TE)
val |= MX51_ECSPI_INT_TEEN;
if (enable & MXC_INT_RR)
val |= MX51_ECSPI_INT_RREN;
if (enable & MXC_INT_RDR)
val |= MX51_ECSPI_INT_RDREN;
writel(val, spi_imx->base + MX51_ECSPI_INT);
}
static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
{
u32 reg;
reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
reg |= MX51_ECSPI_CTRL_XCH;
writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
}
static void mx51_ecspi_disable(struct spi_imx_data *spi_imx)
{
u32 ctrl;
ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
ctrl &= ~MX51_ECSPI_CTRL_ENABLE;
writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
}
static int mx51_ecspi_channel(const struct spi_device *spi)
{
if (!spi_get_csgpiod(spi, 0))
return spi_get_chipselect(spi, 0);
return spi->controller->unused_native_cs;
}
static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
struct spi_message *msg)
{
struct spi_device *spi = msg->spi;
struct spi_transfer *xfer;
u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
u32 min_speed_hz = ~0U;
u32 testreg, delay;
u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
u32 current_cfg = cfg;
int channel = mx51_ecspi_channel(spi);
/* set Host or Target mode */
if (spi_imx->target_mode)
ctrl &= ~MX51_ECSPI_CTRL_MODE_MASK;
else
ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
/*
* Enable SPI_RDY handling (falling edge/level triggered).
*/
if (spi->mode & SPI_READY)
ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
/* set chip select to use */
ctrl |= MX51_ECSPI_CTRL_CS(channel);
/*
* The ctrl register must be written first, with the EN bit set other
* registers must not be written to.
*/
writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
testreg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
if (spi->mode & SPI_LOOP)
testreg |= MX51_ECSPI_TESTREG_LBC;
else
testreg &= ~MX51_ECSPI_TESTREG_LBC;
writel(testreg, spi_imx->base + MX51_ECSPI_TESTREG);
/*
* eCSPI burst completion by Chip Select signal in Target mode
* is not functional for imx53 Soc, config SPI burst completed when
* BURST_LENGTH + 1 bits are received
*/
if (spi_imx->target_mode && is_imx53_ecspi(spi_imx))
cfg &= ~MX51_ECSPI_CONFIG_SBBCTRL(channel);
else
cfg |= MX51_ECSPI_CONFIG_SBBCTRL(channel);
if (spi->mode & SPI_CPOL) {
cfg |= MX51_ECSPI_CONFIG_SCLKPOL(channel);
cfg |= MX51_ECSPI_CONFIG_SCLKCTL(channel);
} else {
cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(channel);
cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(channel);
}
if (spi->mode & SPI_MOSI_IDLE_LOW)
cfg |= MX51_ECSPI_CONFIG_DATACTL(channel);
else
cfg &= ~MX51_ECSPI_CONFIG_DATACTL(channel);
if (spi->mode & SPI_CS_HIGH)
cfg |= MX51_ECSPI_CONFIG_SSBPOL(channel);
else
cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(channel);
if (cfg == current_cfg)
return 0;
writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
/*
* Wait until the changes in the configuration register CONFIGREG
* propagate into the hardware. It takes exactly one tick of the
* SCLK clock, but we will wait two SCLK clock just to be sure. The
* effect of the delay it takes for the hardware to apply changes
* is noticable if the SCLK clock run very slow. In such a case, if
* the polarity of SCLK should be inverted, the GPIO ChipSelect might
* be asserted before the SCLK polarity changes, which would disrupt
* the SPI communication as the device on the other end would consider
* the change of SCLK polarity as a clock tick already.
*
* Because spi_imx->spi_bus_clk is only set in prepare_message
* callback, iterate over all the transfers in spi_message, find the
* one with lowest bus frequency, and use that bus frequency for the
* delay calculation. In case all transfers have speed_hz == 0, then
* min_speed_hz is ~0 and the resulting delay is zero.
*/
list_for_each_entry(xfer, &msg->transfers, transfer_list) {
if (!xfer->speed_hz)
continue;
min_speed_hz = min(xfer->speed_hz, min_speed_hz);
}
delay = (2 * 1000000) / min_speed_hz;
if (likely(delay < 10)) /* SCLK is faster than 200 kHz */
udelay(delay);
else /* SCLK is _very_ slow */
usleep_range(delay, delay + 10);
return 0;
}
static void mx51_configure_cpha(struct spi_imx_data *spi_imx,
struct spi_device *spi)
{
bool cpha = (spi->mode & SPI_CPHA);
bool flip_cpha = (spi->mode & SPI_RX_CPHA_FLIP) && spi_imx->rx_only;
u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
int channel = mx51_ecspi_channel(spi);
/* Flip cpha logical value iff flip_cpha */
cpha ^= flip_cpha;
if (cpha)
cfg |= MX51_ECSPI_CONFIG_SCLKPHA(channel);
else
cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(channel);
writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
}
static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
struct spi_device *spi)
{
u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
u32 clk;
/* Clear BL field and set the right value */
ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
if (spi_imx->target_mode && is_imx53_ecspi(spi_imx))
ctrl |= (spi_imx->target_burst * 8 - 1)
<< MX51_ECSPI_CTRL_BL_OFFSET;
else {
if (spi_imx->usedma) {
ctrl |= (spi_imx->bits_per_word *
spi_imx_bytes_per_word(spi_imx->bits_per_word) - 1)
<< MX51_ECSPI_CTRL_BL_OFFSET;
} else {
if (spi_imx->count >= MX51_ECSPI_CTRL_MAX_BURST)
ctrl |= (MX51_ECSPI_CTRL_MAX_BURST - 1)
<< MX51_ECSPI_CTRL_BL_OFFSET;
else
ctrl |= (spi_imx->count * spi_imx->bits_per_word - 1)
<< MX51_ECSPI_CTRL_BL_OFFSET;
}
}
/* set clock speed */
ctrl &= ~(0xf << MX51_ECSPI_CTRL_POSTDIV_OFFSET |
0xf << MX51_ECSPI_CTRL_PREDIV_OFFSET);
ctrl |= mx51_ecspi_clkdiv(spi_imx, spi_imx->spi_bus_clk, &clk);
spi_imx->spi_bus_clk = clk;
mx51_configure_cpha(spi_imx, spi);
/*
* ERR009165: work in XHC mode instead of SMC as PIO on the chips
* before i.mx6ul.
*/
if (spi_imx->usedma && spi_imx->devtype_data->tx_glitch_fixed)
ctrl |= MX51_ECSPI_CTRL_SMC;
else
ctrl &= ~MX51_ECSPI_CTRL_SMC;
writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
return 0;
}
static void mx51_setup_wml(struct spi_imx_data *spi_imx)
{
u32 tx_wml = 0;
if (spi_imx->devtype_data->tx_glitch_fixed)
tx_wml = spi_imx->wml;
/*
* Configure the DMA register: setup the watermark
* and enable DMA request.
*/
writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) |
MX51_ECSPI_DMA_TX_WML(tx_wml) |
MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
}
static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
{
return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
}
static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
{
/* drain receive buffer */
while (mx51_ecspi_rx_available(spi_imx))
readl(spi_imx->base + MXC_CSPIRXDATA);
}
#define MX31_INTREG_TEEN (1 << 0)
#define MX31_INTREG_RREN (1 << 3)
#define MX31_CSPICTRL_ENABLE (1 << 0)
#define MX31_CSPICTRL_HOST (1 << 1)
#define MX31_CSPICTRL_XCH (1 << 2)
#define MX31_CSPICTRL_SMC (1 << 3)
#define MX31_CSPICTRL_POL (1 << 4)
#define MX31_CSPICTRL_PHA (1 << 5)
#define MX31_CSPICTRL_SSCTL (1 << 6)
#define MX31_CSPICTRL_SSPOL (1 << 7)
#define MX31_CSPICTRL_BC_SHIFT 8
#define MX35_CSPICTRL_BL_SHIFT 20
#define MX31_CSPICTRL_CS_SHIFT 24
#define MX35_CSPICTRL_CS_SHIFT 12
#define MX31_CSPICTRL_DR_SHIFT 16
#define MX31_CSPI_DMAREG 0x10
#define MX31_DMAREG_RH_DEN (1<<4)
#define MX31_DMAREG_TH_DEN (1<<1)
#define MX31_CSPISTATUS 0x14
#define MX31_STATUS_RR (1 << 3)
#define MX31_CSPI_TESTREG 0x1C
#define MX31_TEST_LBC (1 << 14)
/* These functions also work for the i.MX35, but be aware that
* the i.MX35 has a slightly different register layout for bits
* we do not use here.
*/
static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
{
unsigned int val = 0;
if (enable & MXC_INT_TE)
val |= MX31_INTREG_TEEN;
if (enable & MXC_INT_RR)
val |= MX31_INTREG_RREN;
writel(val, spi_imx->base + MXC_CSPIINT);
}
static void mx31_trigger(struct spi_imx_data *spi_imx)
{
unsigned int reg;
reg = readl(spi_imx->base + MXC_CSPICTRL);
reg |= MX31_CSPICTRL_XCH;
writel(reg, spi_imx->base + MXC_CSPICTRL);
}
static int mx31_prepare_message(struct spi_imx_data *spi_imx,
struct spi_message *msg)
{
return 0;
}
static int mx31_prepare_transfer(struct spi_imx_data *spi_imx,
struct spi_device *spi)
{
unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_HOST;
unsigned int clk;
reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
MX31_CSPICTRL_DR_SHIFT;
spi_imx->spi_bus_clk = clk;
if (is_imx35_cspi(spi_imx)) {
reg |= (spi_imx->bits_per_word - 1) << MX35_CSPICTRL_BL_SHIFT;
reg |= MX31_CSPICTRL_SSCTL;
} else {
reg |= (spi_imx->bits_per_word - 1) << MX31_CSPICTRL_BC_SHIFT;
}
if (spi->mode & SPI_CPHA)
reg |= MX31_CSPICTRL_PHA;
if (spi->mode & SPI_CPOL)
reg |= MX31_CSPICTRL_POL;
if (spi->mode & SPI_CS_HIGH)
reg |= MX31_CSPICTRL_SSPOL;
if (!spi_get_csgpiod(spi, 0))
reg |= (spi_get_chipselect(spi, 0)) <<
(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
MX31_CSPICTRL_CS_SHIFT);
if (spi_imx->usedma)
reg |= MX31_CSPICTRL_SMC;
writel(reg, spi_imx->base + MXC_CSPICTRL);
reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
if (spi->mode & SPI_LOOP)
reg |= MX31_TEST_LBC;
else
reg &= ~MX31_TEST_LBC;
writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
if (spi_imx->usedma) {
/*
* configure DMA requests when RXFIFO is half full and
* when TXFIFO is half empty
*/
writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
spi_imx->base + MX31_CSPI_DMAREG);
}
return 0;
}
static int mx31_rx_available(struct spi_imx_data *spi_imx)
{
return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
}
static void mx31_reset(struct spi_imx_data *spi_imx)
{
/* drain receive buffer */
while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
readl(spi_imx->base + MXC_CSPIRXDATA);
}
#define MX21_INTREG_RR (1 << 4)
#define MX21_INTREG_TEEN (1 << 9)
#define MX21_INTREG_RREN (1 << 13)
#define MX21_CSPICTRL_POL (1 << 5)
#define MX21_CSPICTRL_PHA (1 << 6)
#define MX21_CSPICTRL_SSPOL (1 << 8)
#define MX21_CSPICTRL_XCH (1 << 9)
#define MX21_CSPICTRL_ENABLE (1 << 10)
#define MX21_CSPICTRL_HOST (1 << 11)
#define MX21_CSPICTRL_DR_SHIFT 14
#define MX21_CSPICTRL_CS_SHIFT 19
static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
{
unsigned int val = 0;
if (enable & MXC_INT_TE)
val |= MX21_INTREG_TEEN;
if (enable & MXC_INT_RR)
val |= MX21_INTREG_RREN;
writel(val, spi_imx->base + MXC_CSPIINT);
}
static void mx21_trigger(struct spi_imx_data *spi_imx)
{
unsigned int reg;
reg = readl(spi_imx->base + MXC_CSPICTRL);
reg |= MX21_CSPICTRL_XCH;
writel(reg, spi_imx->base + MXC_CSPICTRL);
}
static int mx21_prepare_message(struct spi_imx_data *spi_imx,
struct spi_message *msg)
{
return 0;
}
static int mx21_prepare_transfer(struct spi_imx_data *spi_imx,
struct spi_device *spi)
{
unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_HOST;
unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
unsigned int clk;
reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, spi_imx->spi_bus_clk, max, &clk)
<< MX21_CSPICTRL_DR_SHIFT;
spi_imx->spi_bus_clk = clk;
reg |= spi_imx->bits_per_word - 1;
if (spi->mode & SPI_CPHA)
reg |= MX21_CSPICTRL_PHA;
if (spi->mode & SPI_CPOL)
reg |= MX21_CSPICTRL_POL;
if (spi->mode & SPI_CS_HIGH)
reg |= MX21_CSPICTRL_SSPOL;
if (!spi_get_csgpiod(spi, 0))
reg |= spi_get_chipselect(spi, 0) << MX21_CSPICTRL_CS_SHIFT;
writel(reg, spi_imx->base + MXC_CSPICTRL);
return 0;
}
static int mx21_rx_available(struct spi_imx_data *spi_imx)
{
return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
}
static void mx21_reset(struct spi_imx_data *spi_imx)
{
writel(1, spi_imx->base + MXC_RESET);
}
#define MX1_INTREG_RR (1 << 3)
#define MX1_INTREG_TEEN (1 << 8)
#define MX1_INTREG_RREN (1 << 11)
#define MX1_CSPICTRL_POL (1 << 4)
#define MX1_CSPICTRL_PHA (1 << 5)
#define MX1_CSPICTRL_XCH (1 << 8)
#define MX1_CSPICTRL_ENABLE (1 << 9)
#define MX1_CSPICTRL_HOST (1 << 10)
#define MX1_CSPICTRL_DR_SHIFT 13
static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
{
unsigned int val = 0;
if (enable & MXC_INT_TE)
val |= MX1_INTREG_TEEN;
if (enable & MXC_INT_RR)
val |= MX1_INTREG_RREN;
writel(val, spi_imx->base + MXC_CSPIINT);
}
static void mx1_trigger(struct spi_imx_data *spi_imx)
{
unsigned int reg;
reg = readl(spi_imx->base + MXC_CSPICTRL);
reg |= MX1_CSPICTRL_XCH;
writel(reg, spi_imx->base + MXC_CSPICTRL);
}
static int mx1_prepare_message(struct spi_imx_data *spi_imx,
struct spi_message *msg)
{
return 0;
}
static int mx1_prepare_transfer(struct spi_imx_data *spi_imx,
struct spi_device *spi)
{
unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_HOST;
unsigned int clk;
reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
MX1_CSPICTRL_DR_SHIFT;
spi_imx->spi_bus_clk = clk;
reg |= spi_imx->bits_per_word - 1;
if (spi->mode & SPI_CPHA)
reg |= MX1_CSPICTRL_PHA;
if (spi->mode & SPI_CPOL)
reg |= MX1_CSPICTRL_POL;
writel(reg, spi_imx->base + MXC_CSPICTRL);
return 0;
}
static int mx1_rx_available(struct spi_imx_data *spi_imx)
{
return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
}
static void mx1_reset(struct spi_imx_data *spi_imx)
{
writel(1, spi_imx->base + MXC_RESET);
}
static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
.intctrl = mx1_intctrl,
.prepare_message = mx1_prepare_message,
.prepare_transfer = mx1_prepare_transfer,
.trigger = mx1_trigger,
.rx_available = mx1_rx_available,
.reset = mx1_reset,
.fifo_size = 8,
.has_dmamode = false,
.dynamic_burst = false,
.has_targetmode = false,
.devtype = IMX1_CSPI,
};
static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
.intctrl = mx21_intctrl,
.prepare_message = mx21_prepare_message,
.prepare_transfer = mx21_prepare_transfer,
.trigger = mx21_trigger,
.rx_available = mx21_rx_available,
.reset = mx21_reset,
.fifo_size = 8,
.has_dmamode = false,
.dynamic_burst = false,
.has_targetmode = false,
.devtype = IMX21_CSPI,
};
static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
/* i.mx27 cspi shares the functions with i.mx21 one */
.intctrl = mx21_intctrl,
.prepare_message = mx21_prepare_message,
.prepare_transfer = mx21_prepare_transfer,
.trigger = mx21_trigger,
.rx_available = mx21_rx_available,
.reset = mx21_reset,
.fifo_size = 8,
.has_dmamode = false,
.dynamic_burst = false,
.has_targetmode = false,
.devtype = IMX27_CSPI,
};
static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
.intctrl = mx31_intctrl,
.prepare_message = mx31_prepare_message,
.prepare_transfer = mx31_prepare_transfer,
.trigger = mx31_trigger,
.rx_available = mx31_rx_available,
.reset = mx31_reset,
.fifo_size = 8,
.has_dmamode = false,
.dynamic_burst = false,
.has_targetmode = false,
.devtype = IMX31_CSPI,
};
static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
/* i.mx35 and later cspi shares the functions with i.mx31 one */
.intctrl = mx31_intctrl,
.prepare_message = mx31_prepare_message,
.prepare_transfer = mx31_prepare_transfer,
.trigger = mx31_trigger,
.rx_available = mx31_rx_available,
.reset = mx31_reset,
.fifo_size = 8,
.has_dmamode = true,
.dynamic_burst = false,
.has_targetmode = false,
.devtype = IMX35_CSPI,
};
static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
.intctrl = mx51_ecspi_intctrl,
.prepare_message = mx51_ecspi_prepare_message,
.prepare_transfer = mx51_ecspi_prepare_transfer,
.trigger = mx51_ecspi_trigger,
.rx_available = mx51_ecspi_rx_available,
.reset = mx51_ecspi_reset,
.setup_wml = mx51_setup_wml,
.fifo_size = 64,
.has_dmamode = true,
.dynamic_burst = true,
.has_targetmode = true,
.disable = mx51_ecspi_disable,
.devtype = IMX51_ECSPI,
};
static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
.intctrl = mx51_ecspi_intctrl,
.prepare_message = mx51_ecspi_prepare_message,
.prepare_transfer = mx51_ecspi_prepare_transfer,
.trigger = mx51_ecspi_trigger,
.rx_available = mx51_ecspi_rx_available,
.reset = mx51_ecspi_reset,
.fifo_size = 64,
.has_dmamode = true,
.has_targetmode = true,
.disable = mx51_ecspi_disable,
.devtype = IMX53_ECSPI,
};
static struct spi_imx_devtype_data imx6ul_ecspi_devtype_data = {
.intctrl = mx51_ecspi_intctrl,
.prepare_message = mx51_ecspi_prepare_message,
.prepare_transfer = mx51_ecspi_prepare_transfer,
.trigger = mx51_ecspi_trigger,
.rx_available = mx51_ecspi_rx_available,
.reset = mx51_ecspi_reset,
.setup_wml = mx51_setup_wml,
.fifo_size = 64,
.has_dmamode = true,
.dynamic_burst = true,
.has_targetmode = true,
.tx_glitch_fixed = true,
.disable = mx51_ecspi_disable,
.devtype = IMX51_ECSPI,
};
static const struct of_device_id spi_imx_dt_ids[] = {
{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
{ .compatible = "fsl,imx53-ecspi", .data = &imx53_ecspi_devtype_data, },
{ .compatible = "fsl,imx6ul-ecspi", .data = &imx6ul_ecspi_devtype_data, },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
static void spi_imx_set_burst_len(struct spi_imx_data *spi_imx, int n_bits)
{
u32 ctrl;
ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
ctrl |= ((n_bits - 1) << MX51_ECSPI_CTRL_BL_OFFSET);
writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
}
static void spi_imx_push(struct spi_imx_data *spi_imx)
{
unsigned int burst_len;
/*
* Reload the FIFO when the remaining bytes to be transferred in the
* current burst is 0. This only applies when bits_per_word is a
* multiple of 8.
*/
if (!spi_imx->remainder) {
if (spi_imx->dynamic_burst) {
/* We need to deal unaligned data first */
burst_len = spi_imx->count % MX51_ECSPI_CTRL_MAX_BURST;
if (!burst_len)
burst_len = MX51_ECSPI_CTRL_MAX_BURST;
spi_imx_set_burst_len(spi_imx, burst_len * 8);
spi_imx->remainder = burst_len;
} else {
spi_imx->remainder = spi_imx_bytes_per_word(spi_imx->bits_per_word);
}
}
while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) {
if (!spi_imx->count)
break;
if (spi_imx->dynamic_burst &&
spi_imx->txfifo >= DIV_ROUND_UP(spi_imx->remainder, 4))
break;
spi_imx->tx(spi_imx);
spi_imx->txfifo++;
}
if (!spi_imx->target_mode)
spi_imx->devtype_data->trigger(spi_imx);
}
static irqreturn_t spi_imx_isr(int irq, void *dev_id)
{
struct spi_imx_data *spi_imx = dev_id;
while (spi_imx->txfifo &&
spi_imx->devtype_data->rx_available(spi_imx)) {
spi_imx->rx(spi_imx);
spi_imx->txfifo--;
}
if (spi_imx->count) {
spi_imx_push(spi_imx);
return IRQ_HANDLED;
}
if (spi_imx->txfifo) {
/* No data left to push, but still waiting for rx data,
* enable receive data available interrupt.
*/
spi_imx->devtype_data->intctrl(
spi_imx, MXC_INT_RR);
return IRQ_HANDLED;
}
spi_imx->devtype_data->intctrl(spi_imx, 0);
complete(&spi_imx->xfer_done);
return IRQ_HANDLED;
}
static int spi_imx_dma_configure(struct spi_controller *controller)
{
int ret;
enum dma_slave_buswidth buswidth;
struct dma_slave_config rx = {}, tx = {};
struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
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 = spi_imx->base_phys + MXC_CSPITXDATA;
tx.dst_addr_width = buswidth;
tx.dst_maxburst = spi_imx->wml;
ret = dmaengine_slave_config(controller->dma_tx, &tx);
if (ret) {
dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
return ret;
}
rx.direction = DMA_DEV_TO_MEM;
rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
rx.src_addr_width = buswidth;
rx.src_maxburst = spi_imx->wml;
ret = dmaengine_slave_config(controller->dma_rx, &rx);
if (ret) {
dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
return ret;
}
return 0;
}
static int spi_imx_setupxfer(struct spi_device *spi,
struct spi_transfer *t)
{
struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
if (!t)
return 0;
if (!t->speed_hz) {
if (!spi->max_speed_hz) {
dev_err(&spi->dev, "no speed_hz provided!\n");
return -EINVAL;
}
dev_dbg(&spi->dev, "using spi->max_speed_hz!\n");
spi_imx->spi_bus_clk = spi->max_speed_hz;
} else
spi_imx->spi_bus_clk = t->speed_hz;
spi_imx->bits_per_word = t->bits_per_word;
spi_imx->count = t->len;
/*
* Initialize the functions for transfer. To transfer non byte-aligned
* words, we have to use multiple word-size bursts, we can't use
* dynamic_burst in that case.
*/
if (spi_imx->devtype_data->dynamic_burst && !spi_imx->target_mode &&
!(spi->mode & SPI_CS_WORD) &&
(spi_imx->bits_per_word == 8 ||
spi_imx->bits_per_word == 16 ||
spi_imx->bits_per_word == 32)) {
spi_imx->rx = spi_imx_buf_rx_swap;
spi_imx->tx = spi_imx_buf_tx_swap;
spi_imx->dynamic_burst = 1;
} else {
if (spi_imx->bits_per_word <= 8) {
spi_imx->rx = spi_imx_buf_rx_u8;
spi_imx->tx = spi_imx_buf_tx_u8;
} else if (spi_imx->bits_per_word <= 16) {
spi_imx->rx = spi_imx_buf_rx_u16;
spi_imx->tx = spi_imx_buf_tx_u16;
} else {
spi_imx->rx = spi_imx_buf_rx_u32;
spi_imx->tx = spi_imx_buf_tx_u32;
}
spi_imx->dynamic_burst = 0;
}
if (spi_imx_can_dma(spi_imx->controller, spi, t))
spi_imx->usedma = true;
else
spi_imx->usedma = false;
spi_imx->rx_only = ((t->tx_buf == NULL)
|| (t->tx_buf == spi->controller->dummy_tx));
if (is_imx53_ecspi(spi_imx) && spi_imx->target_mode) {
spi_imx->rx = mx53_ecspi_rx_target;
spi_imx->tx = mx53_ecspi_tx_target;
spi_imx->target_burst = t->len;
}
spi_imx->devtype_data->prepare_transfer(spi_imx, spi);
return 0;
}
static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
{
struct spi_controller *controller = spi_imx->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 spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
struct spi_controller *controller)
{
int ret;
spi_imx->wml = spi_imx->devtype_data->fifo_size / 2;
/* 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 : */
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(&spi_imx->dma_rx_completion);
init_completion(&spi_imx->dma_tx_completion);
controller->can_dma = spi_imx_can_dma;
controller->max_dma_len = MAX_SDMA_BD_BYTES;
spi_imx->controller->flags = SPI_CONTROLLER_MUST_RX |
SPI_CONTROLLER_MUST_TX;
return 0;
err:
spi_imx_sdma_exit(spi_imx);
return ret;
}
static void spi_imx_dma_rx_callback(void *cookie)
{
struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
complete(&spi_imx->dma_rx_completion);
}
static void spi_imx_dma_tx_callback(void *cookie)
{
struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
complete(&spi_imx->dma_tx_completion);
}
static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
{
unsigned long timeout = 0;
/* Time with actual data transfer and CS change delay related to HW */
timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
/* Add extra second for scheduler related activities */
timeout += 1;
/* Double calculated timeout */
return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
}
static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
struct spi_transfer *transfer)
{
struct dma_async_tx_descriptor *desc_tx, *desc_rx;
unsigned long transfer_timeout;
unsigned long timeout;
struct spi_controller *controller = spi_imx->controller;
struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
struct scatterlist *last_sg = sg_last(rx->sgl, rx->nents);
unsigned int bytes_per_word, i;
int ret;
/* Get the right burst length from the last sg to ensure no tail data */
bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
if (!(sg_dma_len(last_sg) % (i * bytes_per_word)))
break;
}
/* Use 1 as wml in case no available burst length got */
if (i == 0)
i = 1;
spi_imx->wml = i;
ret = spi_imx_dma_configure(controller);
if (ret)
goto dma_failure_no_start;
if (!spi_imx->devtype_data->setup_wml) {
dev_err(spi_imx->dev, "No setup_wml()?\n");
ret = -EINVAL;
goto dma_failure_no_start;
}
spi_imx->devtype_data->setup_wml(spi_imx);
/*
* The TX DMA setup starts the transfer, so make sure RX is configured
* before TX.
*/
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) {
ret = -EINVAL;
goto dma_failure_no_start;
}
desc_rx->callback = spi_imx_dma_rx_callback;
desc_rx->callback_param = (void *)spi_imx;
dmaengine_submit(desc_rx);
reinit_completion(&spi_imx->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);
dmaengine_terminate_all(controller->dma_rx);
return -EINVAL;
}
desc_tx->callback = spi_imx_dma_tx_callback;
desc_tx->callback_param = (void *)spi_imx;
dmaengine_submit(desc_tx);
reinit_completion(&spi_imx->dma_tx_completion);
dma_async_issue_pending(controller->dma_tx);
transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
/* Wait SDMA to finish the data transfer.*/
timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
transfer_timeout);
if (!timeout) {
dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
dmaengine_terminate_all(controller->dma_tx);
dmaengine_terminate_all(controller->dma_rx);
return -ETIMEDOUT;
}
timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
transfer_timeout);
if (!timeout) {
dev_err(&controller->dev, "I/O Error in DMA RX\n");
spi_imx->devtype_data->reset(spi_imx);
dmaengine_terminate_all(controller->dma_rx);
return -ETIMEDOUT;
}
return 0;
/* fallback to pio */
dma_failure_no_start:
transfer->error |= SPI_TRANS_FAIL_NO_START;
return ret;
}
static int spi_imx_pio_transfer(struct spi_device *spi,
struct spi_transfer *transfer)
{
struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
unsigned long transfer_timeout;
unsigned long timeout;
spi_imx->tx_buf = transfer->tx_buf;
spi_imx->rx_buf = transfer->rx_buf;
spi_imx->count = transfer->len;
spi_imx->txfifo = 0;
spi_imx->remainder = 0;
reinit_completion(&spi_imx->xfer_done);
spi_imx_push(spi_imx);
spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
transfer_timeout);
if (!timeout) {
dev_err(&spi->dev, "I/O Error in PIO\n");
spi_imx->devtype_data->reset(spi_imx);
return -ETIMEDOUT;
}
return 0;
}
static int spi_imx_poll_transfer(struct spi_device *spi,
struct spi_transfer *transfer)
{
struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
unsigned long timeout;
spi_imx->tx_buf = transfer->tx_buf;
spi_imx->rx_buf = transfer->rx_buf;
spi_imx->count = transfer->len;
spi_imx->txfifo = 0;
spi_imx->remainder = 0;
/* fill in the fifo before timeout calculations if we are
* interrupted here, then the data is getting transferred by
* the HW while we are interrupted
*/
spi_imx_push(spi_imx);
timeout = spi_imx_calculate_timeout(spi_imx, transfer->len) + jiffies;
while (spi_imx->txfifo) {
/* RX */
while (spi_imx->txfifo &&
spi_imx->devtype_data->rx_available(spi_imx)) {
spi_imx->rx(spi_imx);
spi_imx->txfifo--;
}
/* TX */
if (spi_imx->count) {
spi_imx_push(spi_imx);
continue;
}
if (spi_imx->txfifo &&
time_after(jiffies, timeout)) {
dev_err_ratelimited(&spi->dev,
"timeout period reached: jiffies: %lu- falling back to interrupt mode\n",
jiffies - timeout);
/* fall back to interrupt mode */
return spi_imx_pio_transfer(spi, transfer);
}
}
return 0;
}
static int spi_imx_pio_transfer_target(struct spi_device *spi,
struct spi_transfer *transfer)
{
struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
int ret = 0;
if (is_imx53_ecspi(spi_imx) &&
transfer->len > MX53_MAX_TRANSFER_BYTES) {
dev_err(&spi->dev, "Transaction too big, max size is %d bytes\n",
MX53_MAX_TRANSFER_BYTES);
return -EMSGSIZE;
}
spi_imx->tx_buf = transfer->tx_buf;
spi_imx->rx_buf = transfer->rx_buf;
spi_imx->count = transfer->len;
spi_imx->txfifo = 0;
spi_imx->remainder = 0;
reinit_completion(&spi_imx->xfer_done);
spi_imx->target_aborted = false;
spi_imx_push(spi_imx);
spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE | MXC_INT_RDR);
if (wait_for_completion_interruptible(&spi_imx->xfer_done) ||
spi_imx->target_aborted) {
dev_dbg(&spi->dev, "interrupted\n");
ret = -EINTR;
}
/* ecspi has a HW issue when works in Target mode,
* after 64 words writtern to TXFIFO, even TXFIFO becomes empty,
* ECSPI_TXDATA keeps shift out the last word data,
* so we have to disable ECSPI when in target mode after the
* transfer completes
*/
if (spi_imx->devtype_data->disable)
spi_imx->devtype_data->disable(spi_imx);
return ret;
}
static int spi_imx_transfer_one(struct spi_controller *controller,
struct spi_device *spi,
struct spi_transfer *transfer)
{
struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
unsigned long hz_per_byte, byte_limit;
spi_imx_setupxfer(spi, transfer);
transfer->effective_speed_hz = spi_imx->spi_bus_clk;
/* flush rxfifo before transfer */
while (spi_imx->devtype_data->rx_available(spi_imx))
readl(spi_imx->base + MXC_CSPIRXDATA);
if (spi_imx->target_mode)
return spi_imx_pio_transfer_target(spi, transfer);
/*
* If we decided in spi_imx_can_dma() that we want to do a DMA
* transfer, the SPI transfer has already been mapped, so we
* have to do the DMA transfer here.
*/
if (spi_imx->usedma)
return spi_imx_dma_transfer(spi_imx, transfer);
/*
* Calculate the estimated time in us the transfer runs. Find
* the number of Hz per byte per polling limit.
*/
hz_per_byte = polling_limit_us ? ((8 + 4) * USEC_PER_SEC) / polling_limit_us : 0;
byte_limit = hz_per_byte ? transfer->effective_speed_hz / hz_per_byte : 1;
/* run in polling mode for short transfers */
if (transfer->len < byte_limit)
return spi_imx_poll_transfer(spi, transfer);
return spi_imx_pio_transfer(spi, transfer);
}
static int spi_imx_setup(struct spi_device *spi)
{
dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
spi->mode, spi->bits_per_word, spi->max_speed_hz);
return 0;
}
static void spi_imx_cleanup(struct spi_device *spi)
{
}
static int
spi_imx_prepare_message(struct spi_controller *controller, struct spi_message *msg)
{
struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
int ret;
ret = pm_runtime_resume_and_get(spi_imx->dev);
if (ret < 0) {
dev_err(spi_imx->dev, "failed to enable clock\n");
return ret;
}
ret = spi_imx->devtype_data->prepare_message(spi_imx, msg);
if (ret) {
pm_runtime_mark_last_busy(spi_imx->dev);
pm_runtime_put_autosuspend(spi_imx->dev);
}
return ret;
}
static int
spi_imx_unprepare_message(struct spi_controller *controller, struct spi_message *msg)
{
struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
pm_runtime_mark_last_busy(spi_imx->dev);
pm_runtime_put_autosuspend(spi_imx->dev);
return 0;
}
static int spi_imx_target_abort(struct spi_controller *controller)
{
struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
spi_imx->target_aborted = true;
complete(&spi_imx->xfer_done);
return 0;
}
static int spi_imx_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct spi_controller *controller;
struct spi_imx_data *spi_imx;
struct resource *res;
int ret, irq, spi_drctl;
const struct spi_imx_devtype_data *devtype_data =
of_device_get_match_data(&pdev->dev);
bool target_mode;
u32 val;
target_mode = devtype_data->has_targetmode &&
of_property_read_bool(np, "spi-slave");
if (target_mode)
controller = spi_alloc_target(&pdev->dev,
sizeof(struct spi_imx_data));
else
controller = spi_alloc_host(&pdev->dev,
sizeof(struct spi_imx_data));
if (!controller)
return -ENOMEM;
ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
if ((ret < 0) || (spi_drctl >= 0x3)) {
/* '11' is reserved */
spi_drctl = 0;
}
platform_set_drvdata(pdev, controller);
controller->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
controller->bus_num = np ? -1 : pdev->id;
controller->use_gpio_descriptors = true;
spi_imx = spi_controller_get_devdata(controller);
spi_imx->controller = controller;
spi_imx->dev = &pdev->dev;
spi_imx->target_mode = target_mode;
spi_imx->devtype_data = devtype_data;
/*
* Get number of chip selects from device properties. This can be
* coming from device tree or boardfiles, if it is not defined,
* a default value of 3 chip selects will be used, as all the legacy
* board files have <= 3 chip selects.
*/
if (!device_property_read_u32(&pdev->dev, "num-cs", &val))
controller->num_chipselect = val;
else
controller->num_chipselect = 3;
controller->transfer_one = spi_imx_transfer_one;
controller->setup = spi_imx_setup;
controller->cleanup = spi_imx_cleanup;
controller->prepare_message = spi_imx_prepare_message;
controller->unprepare_message = spi_imx_unprepare_message;
controller->target_abort = spi_imx_target_abort;
controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_NO_CS |
SPI_MOSI_IDLE_LOW;
if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
is_imx53_ecspi(spi_imx))
controller->mode_bits |= SPI_LOOP | SPI_READY;
if (is_imx51_ecspi(spi_imx) || is_imx53_ecspi(spi_imx))
controller->mode_bits |= SPI_RX_CPHA_FLIP;
if (is_imx51_ecspi(spi_imx) &&
device_property_read_u32(&pdev->dev, "cs-gpios", NULL))
/*
* When using HW-CS implementing SPI_CS_WORD can be done by just
* setting the burst length to the word size. This is
* considerably faster than manually controlling the CS.
*/
controller->mode_bits |= SPI_CS_WORD;
if (is_imx51_ecspi(spi_imx) || is_imx53_ecspi(spi_imx)) {
controller->max_native_cs = 4;
controller->flags |= SPI_CONTROLLER_GPIO_SS;
}
spi_imx->spi_drctl = spi_drctl;
init_completion(&spi_imx->xfer_done);
spi_imx->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
if (IS_ERR(spi_imx->base)) {
ret = PTR_ERR(spi_imx->base);
goto out_controller_put;
}
spi_imx->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, spi_imx_isr, 0,
dev_name(&pdev->dev), spi_imx);
if (ret) {
dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
goto out_controller_put;
}
spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
if (IS_ERR(spi_imx->clk_ipg)) {
ret = PTR_ERR(spi_imx->clk_ipg);
goto out_controller_put;
}
spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
if (IS_ERR(spi_imx->clk_per)) {
ret = PTR_ERR(spi_imx->clk_per);
goto out_controller_put;
}
ret = clk_prepare_enable(spi_imx->clk_per);
if (ret)
goto out_controller_put;
ret = clk_prepare_enable(spi_imx->clk_ipg);
if (ret)
goto out_put_per;
pm_runtime_set_autosuspend_delay(spi_imx->dev, MXC_RPM_TIMEOUT);
pm_runtime_use_autosuspend(spi_imx->dev);
pm_runtime_get_noresume(spi_imx->dev);
pm_runtime_set_active(spi_imx->dev);
pm_runtime_enable(spi_imx->dev);
spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
/*
* Only validated on i.mx35 and i.mx6 now, can remove the constraint
* if validated on other chips.
*/
if (spi_imx->devtype_data->has_dmamode) {
ret = spi_imx_sdma_init(&pdev->dev, spi_imx, controller);
if (ret == -EPROBE_DEFER)
goto out_runtime_pm_put;
if (ret < 0)
dev_dbg(&pdev->dev, "dma setup error %d, use pio\n",
ret);
}
spi_imx->devtype_data->reset(spi_imx);
spi_imx->devtype_data->intctrl(spi_imx, 0);
controller->dev.of_node = pdev->dev.of_node;
ret = spi_register_controller(controller);
if (ret) {
dev_err_probe(&pdev->dev, ret, "register controller failed\n");
goto out_register_controller;
}
pm_runtime_mark_last_busy(spi_imx->dev);
pm_runtime_put_autosuspend(spi_imx->dev);
return ret;
out_register_controller:
if (spi_imx->devtype_data->has_dmamode)
spi_imx_sdma_exit(spi_imx);
out_runtime_pm_put:
pm_runtime_dont_use_autosuspend(spi_imx->dev);
pm_runtime_set_suspended(&pdev->dev);
pm_runtime_disable(spi_imx->dev);
clk_disable_unprepare(spi_imx->clk_ipg);
out_put_per:
clk_disable_unprepare(spi_imx->clk_per);
out_controller_put:
spi_controller_put(controller);
return ret;
}
static void spi_imx_remove(struct platform_device *pdev)
{
struct spi_controller *controller = platform_get_drvdata(pdev);
struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
int ret;
spi_unregister_controller(controller);
ret = pm_runtime_get_sync(spi_imx->dev);
if (ret >= 0)
writel(0, spi_imx->base + MXC_CSPICTRL);
else
dev_warn(spi_imx->dev, "failed to enable clock, skip hw disable\n");
pm_runtime_dont_use_autosuspend(spi_imx->dev);
pm_runtime_put_sync(spi_imx->dev);
pm_runtime_disable(spi_imx->dev);
spi_imx_sdma_exit(spi_imx);
}
static int __maybe_unused spi_imx_runtime_resume(struct device *dev)
{
struct spi_controller *controller = dev_get_drvdata(dev);
struct spi_imx_data *spi_imx;
int ret;
spi_imx = spi_controller_get_devdata(controller);
ret = clk_prepare_enable(spi_imx->clk_per);
if (ret)
return ret;
ret = clk_prepare_enable(spi_imx->clk_ipg);
if (ret) {
clk_disable_unprepare(spi_imx->clk_per);
return ret;
}
return 0;
}
static int __maybe_unused spi_imx_runtime_suspend(struct device *dev)
{
struct spi_controller *controller = dev_get_drvdata(dev);
struct spi_imx_data *spi_imx;
spi_imx = spi_controller_get_devdata(controller);
clk_disable_unprepare(spi_imx->clk_per);
clk_disable_unprepare(spi_imx->clk_ipg);
return 0;
}
static int __maybe_unused spi_imx_suspend(struct device *dev)
{
pinctrl_pm_select_sleep_state(dev);
return 0;
}
static int __maybe_unused spi_imx_resume(struct device *dev)
{
pinctrl_pm_select_default_state(dev);
return 0;
}
static const struct dev_pm_ops imx_spi_pm = {
SET_RUNTIME_PM_OPS(spi_imx_runtime_suspend,
spi_imx_runtime_resume, NULL)
SET_SYSTEM_SLEEP_PM_OPS(spi_imx_suspend, spi_imx_resume)
};
static struct platform_driver spi_imx_driver = {
.driver = {
.name = DRIVER_NAME,
.of_match_table = spi_imx_dt_ids,
.pm = &imx_spi_pm,
},
.probe = spi_imx_probe,
.remove_new = spi_imx_remove,
};
module_platform_driver(spi_imx_driver);
MODULE_DESCRIPTION("i.MX SPI Controller driver");
MODULE_AUTHOR("Sascha Hauer, Pengutronix");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" DRIVER_NAME);