2024-04-29 11:40:27

by Wolfram Sang

[permalink] [raw]
Subject: [PATCH 0/8] spi: use 'time_left' instead of 'timeout' with wait_for_*() functions

There is a confusing pattern in the kernel to use a variable named 'timeout' to
store the result of wait_for_*() functions causing patterns like:

timeout = wait_for_completion_timeout(...)
if (!timeout) return -ETIMEDOUT;

with all kinds of permutations. Use 'time_left' as a variable to make the code
obvious and self explaining.

This is part of a tree-wide series. The rest of the patches can be found here
(some parts may still be WIP):

git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux.git i2c/time_left

Because these patches are generated, I audit them before sending. This is why I
will send series step by step. Build bot is happy with these patches, though.
No functional changes intended.

Wolfram Sang (8):
spi: armada-3700: use 'time_left' variable with
wait_for_completion_timeout()
spi: fsl-lpspi: use 'time_left' variable with
wait_for_completion_timeout()
spi: imx: use 'time_left' variable with wait_for_completion_timeout()
spi: pic32-sqi: use 'time_left' variable with
wait_for_completion_timeout()
spi: pic32: use 'time_left' variable with
wait_for_completion_timeout()
spi: sun4i: use 'time_left' variable with
wait_for_completion_timeout()
spi: sun6i: use 'time_left' variable with
wait_for_completion_timeout()
spi: xlp: use 'time_left' variable with wait_for_completion_timeout()

drivers/spi/spi-armada-3700.c | 8 ++++----
drivers/spi/spi-fsl-lpspi.c | 14 +++++++-------
drivers/spi/spi-imx.c | 20 ++++++++++----------
drivers/spi/spi-pic32-sqi.c | 6 +++---
drivers/spi/spi-pic32.c | 6 +++---
drivers/spi/spi-sun4i.c | 9 +++++----
drivers/spi/spi-sun6i.c | 17 +++++++++--------
drivers/spi/spi-xlp.c | 8 ++++----
8 files changed, 45 insertions(+), 43 deletions(-)

--
2.43.0



2024-04-29 11:40:40

by Wolfram Sang

[permalink] [raw]
Subject: [PATCH 2/8] spi: fsl-lpspi: use 'time_left' variable with wait_for_completion_timeout()

There is a confusing pattern in the kernel to use a variable named 'timeout' to
store the result of wait_for_completion_timeout() causing patterns like:

timeout = wait_for_completion_timeout(...)
if (!timeout) return -ETIMEDOUT;

with all kinds of permutations. Use 'time_left' as a variable to make the code
self explaining.

Signed-off-by: Wolfram Sang <[email protected]>
---
drivers/spi/spi-fsl-lpspi.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/spi/spi-fsl-lpspi.c b/drivers/spi/spi-fsl-lpspi.c
index 92a662d1b55c..aa5ed254be46 100644
--- a/drivers/spi/spi-fsl-lpspi.c
+++ b/drivers/spi/spi-fsl-lpspi.c
@@ -553,7 +553,7 @@ static int fsl_lpspi_dma_transfer(struct spi_controller *controller,
{
struct dma_async_tx_descriptor *desc_tx, *desc_rx;
unsigned long transfer_timeout;
- unsigned long timeout;
+ unsigned long time_left;
struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
int ret;

@@ -594,9 +594,9 @@ static int fsl_lpspi_dma_transfer(struct spi_controller *controller,
transfer->len);

/* Wait eDMA to finish the data transfer.*/
- timeout = wait_for_completion_timeout(&fsl_lpspi->dma_tx_completion,
- transfer_timeout);
- if (!timeout) {
+ time_left = wait_for_completion_timeout(&fsl_lpspi->dma_tx_completion,
+ transfer_timeout);
+ if (!time_left) {
dev_err(fsl_lpspi->dev, "I/O Error in DMA TX\n");
dmaengine_terminate_all(controller->dma_tx);
dmaengine_terminate_all(controller->dma_rx);
@@ -604,9 +604,9 @@ static int fsl_lpspi_dma_transfer(struct spi_controller *controller,
return -ETIMEDOUT;
}

- timeout = wait_for_completion_timeout(&fsl_lpspi->dma_rx_completion,
- transfer_timeout);
- if (!timeout) {
+ time_left = wait_for_completion_timeout(&fsl_lpspi->dma_rx_completion,
+ transfer_timeout);
+ if (!time_left) {
dev_err(fsl_lpspi->dev, "I/O Error in DMA RX\n");
dmaengine_terminate_all(controller->dma_tx);
dmaengine_terminate_all(controller->dma_rx);
--
2.43.0


2024-04-29 11:41:06

by Wolfram Sang

[permalink] [raw]
Subject: [PATCH 3/8] spi: imx: use 'time_left' variable with wait_for_completion_timeout()

There is a confusing pattern in the kernel to use a variable named 'timeout' to
store the result of wait_for_completion_timeout() causing patterns like:

timeout = wait_for_completion_timeout(...)
if (!timeout) return -ETIMEDOUT;

with all kinds of permutations. Use 'time_left' as a variable to make the code
self explaining.

Signed-off-by: Wolfram Sang <[email protected]>
---
drivers/spi/spi-imx.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index c3e5cee18bea..f4006c82f867 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -1405,7 +1405,7 @@ static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
{
struct dma_async_tx_descriptor *desc_tx, *desc_rx;
unsigned long transfer_timeout;
- unsigned long timeout;
+ unsigned long time_left;
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);
@@ -1471,18 +1471,18 @@ static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
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,
+ time_left = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
transfer_timeout);
- if (!timeout) {
+ if (!time_left) {
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) {
+ time_left = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
+ transfer_timeout);
+ if (!time_left) {
dev_err(&controller->dev, "I/O Error in DMA RX\n");
spi_imx->devtype_data->reset(spi_imx);
dmaengine_terminate_all(controller->dma_rx);
@@ -1501,7 +1501,7 @@ static int spi_imx_pio_transfer(struct spi_device *spi,
{
struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
unsigned long transfer_timeout;
- unsigned long timeout;
+ unsigned long time_left;

spi_imx->tx_buf = transfer->tx_buf;
spi_imx->rx_buf = transfer->rx_buf;
@@ -1517,9 +1517,9 @@ static int spi_imx_pio_transfer(struct spi_device *spi,

transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);

- timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
- transfer_timeout);
- if (!timeout) {
+ time_left = wait_for_completion_timeout(&spi_imx->xfer_done,
+ transfer_timeout);
+ if (!time_left) {
dev_err(&spi->dev, "I/O Error in PIO\n");
spi_imx->devtype_data->reset(spi_imx);
return -ETIMEDOUT;
--
2.43.0


2024-04-29 11:42:05

by Wolfram Sang

[permalink] [raw]
Subject: [PATCH 7/8] spi: sun6i: use 'time_left' variable with wait_for_completion_timeout()

There is a confusing pattern in the kernel to use a variable named 'timeout' to
store the result of wait_for_completion_timeout() causing patterns like:

timeout = wait_for_completion_timeout(...)
if (!timeout) return -ETIMEDOUT;

with all kinds of permutations. Use 'time_left' as a variable to make the code
self explaining.

Fix to the proper variable type 'unsigned long' while here.

Signed-off-by: Wolfram Sang <[email protected]>
---
drivers/spi/spi-sun6i.c | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/drivers/spi/spi-sun6i.c b/drivers/spi/spi-sun6i.c
index cd018ea1abf1..7bbe7ea0d66a 100644
--- a/drivers/spi/spi-sun6i.c
+++ b/drivers/spi/spi-sun6i.c
@@ -277,7 +277,8 @@ static int sun6i_spi_transfer_one(struct spi_controller *host,
struct spi_transfer *tfr)
{
struct sun6i_spi *sspi = spi_controller_get_devdata(host);
- unsigned int div, div_cdr1, div_cdr2, timeout;
+ unsigned int div, div_cdr1, div_cdr2;
+ unsigned long time_left;
unsigned int start, end, tx_time;
unsigned int trig_level;
unsigned int tx_len = 0, rx_len = 0, nbits = 0;
@@ -488,26 +489,26 @@ static int sun6i_spi_transfer_one(struct spi_controller *host,

tx_time = spi_controller_xfer_timeout(host, tfr);
start = jiffies;
- timeout = wait_for_completion_timeout(&sspi->done,
- msecs_to_jiffies(tx_time));
+ time_left = wait_for_completion_timeout(&sspi->done,
+ msecs_to_jiffies(tx_time));

if (!use_dma) {
sun6i_spi_drain_fifo(sspi);
} else {
- if (timeout && rx_len) {
+ if (time_left && rx_len) {
/*
* Even though RX on the peripheral side has finished
* RX DMA might still be in flight
*/
- timeout = wait_for_completion_timeout(&sspi->dma_rx_done,
- timeout);
- if (!timeout)
+ time_left = wait_for_completion_timeout(&sspi->dma_rx_done,
+ time_left);
+ if (!time_left)
dev_warn(&host->dev, "RX DMA timeout\n");
}
}

end = jiffies;
- if (!timeout) {
+ if (!time_left) {
dev_warn(&host->dev,
"%s: timeout transferring %u bytes@%iHz for %i(%i)ms",
dev_name(&spi->dev), tfr->len, tfr->speed_hz,
--
2.43.0


2024-04-29 12:45:43

by Andre Przywara

[permalink] [raw]
Subject: Re: [PATCH 7/8] spi: sun6i: use 'time_left' variable with wait_for_completion_timeout()

On Mon, 29 Apr 2024 13:28:40 +0200
Wolfram Sang <[email protected]> wrote:

Hi,

> There is a confusing pattern in the kernel to use a variable named 'timeout' to
> store the result of wait_for_completion_timeout() causing patterns like:
>
> timeout = wait_for_completion_timeout(...)
> if (!timeout) return -ETIMEDOUT;
>
> with all kinds of permutations. Use 'time_left' as a variable to make the code
> self explaining.
>
> Fix to the proper variable type 'unsigned long' while here.
>
> Signed-off-by: Wolfram Sang <[email protected]>
> ---
> drivers/spi/spi-sun6i.c | 17 +++++++++--------
> 1 file changed, 9 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/spi/spi-sun6i.c b/drivers/spi/spi-sun6i.c
> index cd018ea1abf1..7bbe7ea0d66a 100644
> --- a/drivers/spi/spi-sun6i.c
> +++ b/drivers/spi/spi-sun6i.c
> @@ -277,7 +277,8 @@ static int sun6i_spi_transfer_one(struct spi_controller *host,
> struct spi_transfer *tfr)
> {
> struct sun6i_spi *sspi = spi_controller_get_devdata(host);
> - unsigned int div, div_cdr1, div_cdr2, timeout;
> + unsigned int div, div_cdr1, div_cdr2;
> + unsigned long time_left;
> unsigned int start, end, tx_time;
> unsigned int trig_level;
> unsigned int tx_len = 0, rx_len = 0, nbits = 0;
> @@ -488,26 +489,26 @@ static int sun6i_spi_transfer_one(struct spi_controller *host,
>
> tx_time = spi_controller_xfer_timeout(host, tfr);
> start = jiffies;
> - timeout = wait_for_completion_timeout(&sspi->done,
> - msecs_to_jiffies(tx_time));
> + time_left = wait_for_completion_timeout(&sspi->done,
> + msecs_to_jiffies(tx_time));
>
> if (!use_dma) {
> sun6i_spi_drain_fifo(sspi);
> } else {
> - if (timeout && rx_len) {
> + if (time_left && rx_len) {
> /*
> * Even though RX on the peripheral side has finished
> * RX DMA might still be in flight
> */
> - timeout = wait_for_completion_timeout(&sspi->dma_rx_done,
> - timeout);
> - if (!timeout)
> + time_left = wait_for_completion_timeout(&sspi->dma_rx_done,
> + time_left);

Nit: indentation is off here. Regardless:

Reviewed-by: Andre Przywara <[email protected]>

Cheers,
Andre

> + if (!time_left)
> dev_warn(&host->dev, "RX DMA timeout\n");
> }
> }
>
> end = jiffies;
> - if (!timeout) {
> + if (!time_left) {
> dev_warn(&host->dev,
> "%s: timeout transferring %u bytes@%iHz for %i(%i)ms",
> dev_name(&spi->dev), tfr->len, tfr->speed_hz,


2024-04-29 14:37:21

by Wolfram Sang

[permalink] [raw]
Subject: Re: [PATCH 7/8] spi: sun6i: use 'time_left' variable with wait_for_completion_timeout()


> > - if (!timeout)
> > + time_left = wait_for_completion_timeout(&sspi->dma_rx_done,
> > + time_left);
>
> Nit: indentation is off here. Regardless:

Oh, right. Thanks, will fix!


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2024-04-29 15:36:11

by Jernej Škrabec

[permalink] [raw]
Subject: Re: [PATCH 7/8] spi: sun6i: use 'time_left' variable with wait_for_completion_timeout()

Dne ponedeljek, 29. april 2024 ob 13:28:40 GMT +2 je Wolfram Sang napisal(a):
> There is a confusing pattern in the kernel to use a variable named 'timeout' to
> store the result of wait_for_completion_timeout() causing patterns like:
>
> timeout = wait_for_completion_timeout(...)
> if (!timeout) return -ETIMEDOUT;
>
> with all kinds of permutations. Use 'time_left' as a variable to make the code
> self explaining.
>
> Fix to the proper variable type 'unsigned long' while here.
>
> Signed-off-by: Wolfram Sang <[email protected]>

Acked-by: Jernej Skrabec <[email protected]>

Best regards,
Jernej

> ---
> drivers/spi/spi-sun6i.c | 17 +++++++++--------
> 1 file changed, 9 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/spi/spi-sun6i.c b/drivers/spi/spi-sun6i.c
> index cd018ea1abf1..7bbe7ea0d66a 100644
> --- a/drivers/spi/spi-sun6i.c
> +++ b/drivers/spi/spi-sun6i.c
> @@ -277,7 +277,8 @@ static int sun6i_spi_transfer_one(struct spi_controller *host,
> struct spi_transfer *tfr)
> {
> struct sun6i_spi *sspi = spi_controller_get_devdata(host);
> - unsigned int div, div_cdr1, div_cdr2, timeout;
> + unsigned int div, div_cdr1, div_cdr2;
> + unsigned long time_left;
> unsigned int start, end, tx_time;
> unsigned int trig_level;
> unsigned int tx_len = 0, rx_len = 0, nbits = 0;
> @@ -488,26 +489,26 @@ static int sun6i_spi_transfer_one(struct spi_controller *host,
>
> tx_time = spi_controller_xfer_timeout(host, tfr);
> start = jiffies;
> - timeout = wait_for_completion_timeout(&sspi->done,
> - msecs_to_jiffies(tx_time));
> + time_left = wait_for_completion_timeout(&sspi->done,
> + msecs_to_jiffies(tx_time));
>
> if (!use_dma) {
> sun6i_spi_drain_fifo(sspi);
> } else {
> - if (timeout && rx_len) {
> + if (time_left && rx_len) {
> /*
> * Even though RX on the peripheral side has finished
> * RX DMA might still be in flight
> */
> - timeout = wait_for_completion_timeout(&sspi->dma_rx_done,
> - timeout);
> - if (!timeout)
> + time_left = wait_for_completion_timeout(&sspi->dma_rx_done,
> + time_left);
> + if (!time_left)
> dev_warn(&host->dev, "RX DMA timeout\n");
> }
> }
>
> end = jiffies;
> - if (!timeout) {
> + if (!time_left) {
> dev_warn(&host->dev,
> "%s: timeout transferring %u bytes@%iHz for %i(%i)ms",
> dev_name(&spi->dev), tfr->len, tfr->speed_hz,
>





2024-04-30 01:36:11

by Peng Fan

[permalink] [raw]
Subject: RE: [PATCH 3/8] spi: imx: use 'time_left' variable with wait_for_completion_timeout()

> Subject: [PATCH 3/8] spi: imx: use 'time_left' variable with
> wait_for_completion_timeout()
>
> There is a confusing pattern in the kernel to use a variable named 'timeout' to
> store the result of wait_for_completion_timeout() causing patterns like:
>
> timeout = wait_for_completion_timeout(...)
> if (!timeout) return -ETIMEDOUT;
>
> with all kinds of permutations. Use 'time_left' as a variable to make the code
> self explaining.
>
> Signed-off-by: Wolfram Sang <[email protected]>

Reviewed-by: Peng Fan <[email protected]>
> ---
> drivers/spi/spi-imx.c | 20 ++++++++++----------
> 1 file changed, 10 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index
> c3e5cee18bea..f4006c82f867 100644
> --- a/drivers/spi/spi-imx.c
> +++ b/drivers/spi/spi-imx.c
> @@ -1405,7 +1405,7 @@ static int spi_imx_dma_transfer(struct
> spi_imx_data *spi_imx, {
> struct dma_async_tx_descriptor *desc_tx, *desc_rx;
> unsigned long transfer_timeout;
> - unsigned long timeout;
> + unsigned long time_left;
> 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); @@ -1471,18
> +1471,18 @@ static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
> 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,
> + time_left = wait_for_completion_timeout(&spi_imx-
> >dma_tx_completion,
> transfer_timeout);
> - if (!timeout) {
> + if (!time_left) {
> 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) {
> + time_left = wait_for_completion_timeout(&spi_imx-
> >dma_rx_completion,
> + transfer_timeout);
> + if (!time_left) {
> dev_err(&controller->dev, "I/O Error in DMA RX\n");
> spi_imx->devtype_data->reset(spi_imx);
> dmaengine_terminate_all(controller->dma_rx);
> @@ -1501,7 +1501,7 @@ static int spi_imx_pio_transfer(struct spi_device
> *spi, {
> struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi-
> >controller);
> unsigned long transfer_timeout;
> - unsigned long timeout;
> + unsigned long time_left;
>
> spi_imx->tx_buf = transfer->tx_buf;
> spi_imx->rx_buf = transfer->rx_buf;
> @@ -1517,9 +1517,9 @@ static int spi_imx_pio_transfer(struct spi_device
> *spi,
>
> transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
>
> - timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
> - transfer_timeout);
> - if (!timeout) {
> + time_left = wait_for_completion_timeout(&spi_imx->xfer_done,
> + transfer_timeout);
> + if (!time_left) {
> dev_err(&spi->dev, "I/O Error in PIO\n");
> spi_imx->devtype_data->reset(spi_imx);
> return -ETIMEDOUT;
> --
> 2.43.0
>


2024-05-02 03:57:10

by Mark Brown

[permalink] [raw]
Subject: Re: [PATCH 0/8] spi: use 'time_left' instead of 'timeout' with wait_for_*() functions

On Mon, 29 Apr 2024 13:28:33 +0200, Wolfram Sang wrote:
> There is a confusing pattern in the kernel to use a variable named 'timeout' to
> store the result of wait_for_*() functions causing patterns like:
>
> timeout = wait_for_completion_timeout(...)
> if (!timeout) return -ETIMEDOUT;
>
> with all kinds of permutations. Use 'time_left' as a variable to make the code
> obvious and self explaining.
>
> [...]

Applied to

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

Thanks!

[1/8] spi: armada-3700: use 'time_left' variable with wait_for_completion_timeout()
commit: 7dbbbb1206dd0b695b9a76d3b758c8a689f1aa52
[2/8] spi: fsl-lpspi: use 'time_left' variable with wait_for_completion_timeout()
commit: eef51e99f7b9ecc903a3a9ad9e7ca84dc35c3f52
[3/8] spi: imx: use 'time_left' variable with wait_for_completion_timeout()
commit: eaeac043ab842d2e84616ff0412eec0121c1758c
[4/8] spi: pic32-sqi: use 'time_left' variable with wait_for_completion_timeout()
commit: a7c79e50a26cb619400ccc6294dbd7d8c24a0341
[5/8] spi: pic32: use 'time_left' variable with wait_for_completion_timeout()
commit: e66480aed4a194f278da1e46ec45221b3983216f
[6/8] spi: sun4i: use 'time_left' variable with wait_for_completion_timeout()
commit: 34bed8a33f3a4f69b0ef584ef49f04a671a4a5c2
[7/8] spi: sun6i: use 'time_left' variable with wait_for_completion_timeout()
commit: 83a3f1ba60d6e2f73c9dd2627a8ce41867dbc46b
[8/8] spi: xlp: use 'time_left' variable with wait_for_completion_timeout()
commit: 594aa75d6bdda85b5fd027a5056d8cd1345c1db3

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