[PATCH 5.4 030/108] spi: imx: add a check for speed_hz before calculating the clock

From: Greg Kroah-Hartman
Date: Mon Jul 26 2021 - 12:10:47 EST


From: Clark Wang <xiaoning.wang@xxxxxxx>

[ Upstream commit 4df2f5e1372e9eec8f9e1b4a3025b9be23487d36 ]

When some drivers use spi to send data, spi_transfer->speed_hz is
not assigned. If spidev->max_speed_hz is not assigned as well, it
will cause an error in configuring the clock.
Add a check for these two values before configuring the clock. An
error will be returned when they are not assigned.

Signed-off-by: Clark Wang <xiaoning.wang@xxxxxxx>
Link: https://lore.kernel.org/r/20210408103347.244313-2-xiaoning.wang@xxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/spi/spi-imx.c | 37 +++++++++++++++++++++----------------
1 file changed, 21 insertions(+), 16 deletions(-)

diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index 09c9a1edb2c6..e237481dbbbb 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -64,8 +64,7 @@ struct spi_imx_data;
struct spi_imx_devtype_data {
void (*intctrl)(struct spi_imx_data *, int);
int (*prepare_message)(struct spi_imx_data *, struct spi_message *);
- int (*prepare_transfer)(struct spi_imx_data *, struct spi_device *,
- struct spi_transfer *);
+ int (*prepare_transfer)(struct spi_imx_data *, struct spi_device *);
void (*trigger)(struct spi_imx_data *);
int (*rx_available)(struct spi_imx_data *);
void (*reset)(struct spi_imx_data *);
@@ -564,11 +563,10 @@ static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
}

static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
- struct spi_device *spi,
- struct spi_transfer *t)
+ struct spi_device *spi)
{
u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
- u32 clk = t->speed_hz, delay;
+ u32 clk, delay;

/* Clear BL field and set the right value */
ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
@@ -582,7 +580,7 @@ static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
/* set clock speed */
ctrl &= ~(0xf << MX51_ECSPI_CTRL_POSTDIV_OFFSET |
0xf << MX51_ECSPI_CTRL_PREDIV_OFFSET);
- ctrl |= mx51_ecspi_clkdiv(spi_imx, t->speed_hz, &clk);
+ ctrl |= mx51_ecspi_clkdiv(spi_imx, spi_imx->spi_bus_clk, &clk);
spi_imx->spi_bus_clk = clk;

if (spi_imx->usedma)
@@ -694,13 +692,12 @@ static int mx31_prepare_message(struct spi_imx_data *spi_imx,
}

static int mx31_prepare_transfer(struct spi_imx_data *spi_imx,
- struct spi_device *spi,
- struct spi_transfer *t)
+ struct spi_device *spi)
{
unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
unsigned int clk;

- reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, t->speed_hz, &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;

@@ -799,14 +796,13 @@ static int mx21_prepare_message(struct spi_imx_data *spi_imx,
}

static int mx21_prepare_transfer(struct spi_imx_data *spi_imx,
- struct spi_device *spi,
- struct spi_transfer *t)
+ struct spi_device *spi)
{
unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
unsigned int clk;

- reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, t->speed_hz, max, &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;

@@ -875,13 +871,12 @@ static int mx1_prepare_message(struct spi_imx_data *spi_imx,
}

static int mx1_prepare_transfer(struct spi_imx_data *spi_imx,
- struct spi_device *spi,
- struct spi_transfer *t)
+ struct spi_device *spi)
{
unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
unsigned int clk;

- reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, t->speed_hz, &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;

@@ -1199,6 +1194,16 @@ static int spi_imx_setupxfer(struct spi_device *spi,
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;

/*
@@ -1240,7 +1245,7 @@ static int spi_imx_setupxfer(struct spi_device *spi,
spi_imx->slave_burst = t->len;
}

- spi_imx->devtype_data->prepare_transfer(spi_imx, spi, t);
+ spi_imx->devtype_data->prepare_transfer(spi_imx, spi);

return 0;
}
--
2.30.2