2020-08-07 13:25:17

by Alain Volmat

[permalink] [raw]
Subject: [PATCH 0/5] spi: stm32: various driver fixes

This serie is a reduced version of the serie
[spi: stm32: various driver enhancements] previously sent.

Alain Volmat (1):
spi: stm32: always perform registers configuration prior to transfer

Amelie Delaunay (3):
spi: stm32: fix fifo threshold level in case of short transfer
spi: stm32: fix stm32_spi_prepare_mbr in case of odd clk_rate
spi: stm32: fixes suspend/resume management

Antonio Borneo (1):
spi: stm32h7: fix race condition at end of transfer

drivers/spi/spi-stm32.c | 95 ++++++++++++++++++++++++++++++-------------------
1 file changed, 58 insertions(+), 37 deletions(-)


2020-08-07 13:25:42

by Alain Volmat

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Subject: [PATCH 4/5] spi: stm32: fixes suspend/resume management

From: Amelie Delaunay <[email protected]>

This patch adds pinctrl power management, and reconfigure spi controller
in case of resume.

Fixes: 038ac869c9d2 ("spi: stm32: add runtime PM support")

Signed-off-by: Amelie Delaunay <[email protected]>
Signed-off-by: Alain Volmat <[email protected]>
---
drivers/spi/spi-stm32.c | 27 ++++++++++++++++++++++++---
1 file changed, 24 insertions(+), 3 deletions(-)

diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c
index bdd4e70c3f10..e196dbc5c432 100644
--- a/drivers/spi/spi-stm32.c
+++ b/drivers/spi/spi-stm32.c
@@ -13,6 +13,7 @@
#include <linux/iopoll.h>
#include <linux/module.h>
#include <linux/of_platform.h>
+#include <linux/pinctrl/consumer.h>
#include <linux/pm_runtime.h>
#include <linux/reset.h>
#include <linux/spi/spi.h>
@@ -2004,6 +2005,8 @@ static int stm32_spi_remove(struct platform_device *pdev)

pm_runtime_disable(&pdev->dev);

+ pinctrl_pm_select_sleep_state(&pdev->dev);
+
return 0;
}

@@ -2015,13 +2018,18 @@ static int stm32_spi_runtime_suspend(struct device *dev)

clk_disable_unprepare(spi->clk);

- return 0;
+ return pinctrl_pm_select_sleep_state(dev);
}

static int stm32_spi_runtime_resume(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
struct stm32_spi *spi = spi_master_get_devdata(master);
+ int ret;
+
+ ret = pinctrl_pm_select_default_state(dev);
+ if (ret)
+ return ret;

return clk_prepare_enable(spi->clk);
}
@@ -2051,10 +2059,23 @@ static int stm32_spi_resume(struct device *dev)
return ret;

ret = spi_master_resume(master);
- if (ret)
+ if (ret) {
clk_disable_unprepare(spi->clk);
+ return ret;
+ }

- return ret;
+ ret = pm_runtime_get_sync(dev);
+ if (ret) {
+ dev_err(dev, "Unable to power device:%d\n", ret);
+ return ret;
+ }
+
+ spi->cfg->config(spi);
+
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_put_autosuspend(dev);
+
+ return 0;
}
#endif

--
2.7.4

2020-08-07 13:26:21

by Alain Volmat

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Subject: [PATCH 3/5] spi: stm32: fix stm32_spi_prepare_mbr in case of odd clk_rate

From: Amelie Delaunay <[email protected]>

Fix spi->clk_rate when it is odd to the nearest lowest even value because
minimum SPI divider is 2.

Signed-off-by: Amelie Delaunay <[email protected]>
Signed-off-by: Alain Volmat <[email protected]>
---
drivers/spi/spi-stm32.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c
index 005bc16bdf2a..bdd4e70c3f10 100644
--- a/drivers/spi/spi-stm32.c
+++ b/drivers/spi/spi-stm32.c
@@ -441,7 +441,8 @@ static int stm32_spi_prepare_mbr(struct stm32_spi *spi, u32 speed_hz,
{
u32 div, mbrdiv;

- div = DIV_ROUND_UP(spi->clk_rate, speed_hz);
+ /* Ensure spi->clk_rate is even */
+ div = DIV_ROUND_UP(spi->clk_rate & ~0x1, speed_hz);

/*
* SPI framework set xfer->speed_hz to master->max_speed_hz if
--
2.7.4

2020-08-07 13:26:51

by Alain Volmat

[permalink] [raw]
Subject: [PATCH 1/5] spi: stm32h7: fix race condition at end of transfer

From: Antonio Borneo <[email protected]>

The caller of stm32_spi_transfer_one(), spi_transfer_one_message(),
is waiting for us to call spi_finalize_current_transfer() and will
eventually schedule a new transfer, if available.
We should guarantee that the spi controller is really available
before calling spi_finalize_current_transfer().

Move the call to spi_finalize_current_transfer() _after_ the call
to stm32_spi_disable().

Signed-off-by: Antonio Borneo <[email protected]>
Signed-off-by: Alain Volmat <[email protected]>
---
drivers/spi/spi-stm32.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c
index 4a21feae0103..814a3ec3b8ad 100644
--- a/drivers/spi/spi-stm32.c
+++ b/drivers/spi/spi-stm32.c
@@ -971,8 +971,8 @@ static irqreturn_t stm32h7_spi_irq_thread(int irq, void *dev_id)
spin_unlock_irqrestore(&spi->lock, flags);

if (end) {
- spi_finalize_current_transfer(master);
stm32h7_spi_disable(spi);
+ spi_finalize_current_transfer(master);
}

return IRQ_HANDLED;
--
2.7.4

2020-08-07 13:26:54

by Alain Volmat

[permalink] [raw]
Subject: [PATCH 2/5] spi: stm32: fix fifo threshold level in case of short transfer

From: Amelie Delaunay <[email protected]>

When transfer is shorter than half of the fifo, set the data packet size
up to transfer size instead of up to half of the fifo.
Check also that threshold is set at least to 1 data frame.

Signed-off-by: Amelie Delaunay <[email protected]>
Signed-off-by: Alain Volmat <[email protected]>
---
drivers/spi/spi-stm32.c | 23 +++++++++++++++--------
1 file changed, 15 insertions(+), 8 deletions(-)

diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c
index 814a3ec3b8ad..005bc16bdf2a 100644
--- a/drivers/spi/spi-stm32.c
+++ b/drivers/spi/spi-stm32.c
@@ -467,20 +467,24 @@ static int stm32_spi_prepare_mbr(struct stm32_spi *spi, u32 speed_hz,
/**
* stm32h7_spi_prepare_fthlv - Determine FIFO threshold level
* @spi: pointer to the spi controller data structure
+ * @xfer_len: length of the message to be transferred
*/
-static u32 stm32h7_spi_prepare_fthlv(struct stm32_spi *spi)
+static u32 stm32h7_spi_prepare_fthlv(struct stm32_spi *spi, u32 xfer_len)
{
- u32 fthlv, half_fifo;
+ u32 fthlv, half_fifo, packet;

/* data packet should not exceed 1/2 of fifo space */
half_fifo = (spi->fifo_size / 2);

+ /* data_packet should not exceed transfer length */
+ packet = (half_fifo > xfer_len) ? xfer_len : half_fifo;
+
if (spi->cur_bpw <= 8)
- fthlv = half_fifo;
+ fthlv = packet;
else if (spi->cur_bpw <= 16)
- fthlv = half_fifo / 2;
+ fthlv = packet / 2;
else
- fthlv = half_fifo / 4;
+ fthlv = packet / 4;

/* align packet size with data registers access */
if (spi->cur_bpw > 8)
@@ -488,6 +492,9 @@ static u32 stm32h7_spi_prepare_fthlv(struct stm32_spi *spi)
else
fthlv -= (fthlv % 4); /* multiple of 4 */

+ if (!fthlv)
+ fthlv = 1;
+
return fthlv;
}

@@ -1393,7 +1400,7 @@ static void stm32h7_spi_set_bpw(struct stm32_spi *spi)
cfg1_setb |= (bpw << STM32H7_SPI_CFG1_DSIZE_SHIFT) &
STM32H7_SPI_CFG1_DSIZE;

- spi->cur_fthlv = stm32h7_spi_prepare_fthlv(spi);
+ spi->cur_fthlv = stm32h7_spi_prepare_fthlv(spi, spi->cur_xferlen);
fthlv = spi->cur_fthlv - 1;

cfg1_clrb |= STM32H7_SPI_CFG1_FTHLV;
@@ -1588,6 +1595,8 @@ static int stm32_spi_transfer_one_setup(struct stm32_spi *spi,

spin_lock_irqsave(&spi->lock, flags);

+ spi->cur_xferlen = transfer->len;
+
if (spi->cur_bpw != transfer->bits_per_word) {
spi->cur_bpw = transfer->bits_per_word;
spi->cfg->set_bpw(spi);
@@ -1635,8 +1644,6 @@ static int stm32_spi_transfer_one_setup(struct stm32_spi *spi,
goto out;
}

- spi->cur_xferlen = transfer->len;
-
dev_dbg(spi->dev, "transfer communication mode set to %d\n",
spi->cur_comm);
dev_dbg(spi->dev,
--
2.7.4

2020-08-07 13:31:15

by Mark Brown

[permalink] [raw]
Subject: Re: [PATCH 2/5] spi: stm32: fix fifo threshold level in case of short transfer

On Fri, Aug 07, 2020 at 03:21:22PM +0200, Alain Volmat wrote:

> + /* data_packet should not exceed transfer length */
> + packet = (half_fifo > xfer_len) ? xfer_len : half_fifo;

Please write normal conditional statements to improve legibility.


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2020-08-10 18:59:59

by Mark Brown

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Subject: Re: [PATCH 0/5] spi: stm32: various driver fixes

On Fri, 7 Aug 2020 15:21:20 +0200, Alain Volmat wrote:
> This serie is a reduced version of the serie
> [spi: stm32: various driver enhancements] previously sent.
>
> Alain Volmat (1):
> spi: stm32: always perform registers configuration prior to transfer
>
> Amelie Delaunay (3):
> spi: stm32: fix fifo threshold level in case of short transfer
> spi: stm32: fix stm32_spi_prepare_mbr in case of odd clk_rate
> spi: stm32: fixes suspend/resume management
>
> [...]

Applied to

https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next

Thanks!

[1/4] spi: stm32h7: fix race condition at end of transfer
commit: 135dd873d3c76d812ae64c668adef3f2c59ed27f
[2/4] spi: stm32: fix stm32_spi_prepare_mbr in case of odd clk_rate
commit: 9cc61973bf9385b19ff5dda4a2a7e265fcba85e4
[3/4] spi: stm32: fixes suspend/resume management
commit: db96bf976a4fc65439be0b4524c0d41427d98814
[4/4] spi: stm32: always perform registers configuration prior to transfer
commit: 60ccb3515fc61a0124c70aa37317f75b67560024

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark