This change is necessary for spidev devices (e.g. /dev/spidev3.0) working
in the slave mode (like NXP's dspi driver for Vybrid SoC).
When SPI HW works in this mode - the master is responsible for providing
CS and CLK signals. However, when some fault happens - like for example
distortion on SPI lines - the SPI Linux driver needs a chance to recover
from this abnormal situation and prepare itself for next (correct)
transmission.
This change doesn't pose any threat on drivers working in master mode as
spi_slave_abort() function checks if SPI slave mode is supported.
Signed-off-by: Lukasz Majewski <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Mark Brown <[email protected]>
Reported-by: kbuild test robot <[email protected]>
---
Changes for v2:
- Add #ifdef CONFIG_SPI_SLAVE to not compile in spi_slave_abort() on systems
which are only using master mode.
(The spi_slave_abort() is 'protected' by this Kconfig define in drivers/spi.c
file).
This error was spotted by kbuild test robot from Intel.
---
drivers/spi/spidev.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/spi/spidev.c b/drivers/spi/spidev.c
index 255786f2e844..3ea9d8a3e6e8 100644
--- a/drivers/spi/spidev.c
+++ b/drivers/spi/spidev.c
@@ -627,6 +627,9 @@ static int spidev_release(struct inode *inode, struct file *filp)
if (dofree)
kfree(spidev);
}
+#ifdef CONFIG_SPI_SLAVE
+ spi_slave_abort(spidev->spi);
+#endif
mutex_unlock(&device_list_lock);
return 0;
--
2.20.1
The patch
spi: Add call to spi_slave_abort() function when spidev driver is released
has been applied to the spi tree at
https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-5.4
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
From 9f918a728cf86b2757b6a7025e1f46824bfe3155 Mon Sep 17 00:00:00 2001
From: Lukasz Majewski <[email protected]>
Date: Wed, 25 Sep 2019 11:11:42 +0200
Subject: [PATCH] spi: Add call to spi_slave_abort() function when spidev
driver is released
This change is necessary for spidev devices (e.g. /dev/spidev3.0) working
in the slave mode (like NXP's dspi driver for Vybrid SoC).
When SPI HW works in this mode - the master is responsible for providing
CS and CLK signals. However, when some fault happens - like for example
distortion on SPI lines - the SPI Linux driver needs a chance to recover
from this abnormal situation and prepare itself for next (correct)
transmission.
This change doesn't pose any threat on drivers working in master mode as
spi_slave_abort() function checks if SPI slave mode is supported.
Signed-off-by: Lukasz Majewski <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Mark Brown <[email protected]>
Reported-by: kbuild test robot <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Mark Brown <[email protected]>
---
drivers/spi/spidev.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/spi/spidev.c b/drivers/spi/spidev.c
index 255786f2e844..3ea9d8a3e6e8 100644
--- a/drivers/spi/spidev.c
+++ b/drivers/spi/spidev.c
@@ -627,6 +627,9 @@ static int spidev_release(struct inode *inode, struct file *filp)
if (dofree)
kfree(spidev);
}
+#ifdef CONFIG_SPI_SLAVE
+ spi_slave_abort(spidev->spi);
+#endif
mutex_unlock(&device_list_lock);
return 0;
--
2.20.1
On Wed, Sep 25, 2019 at 11:11:42AM +0200, Lukasz Majewski wrote:
> This change is necessary for spidev devices (e.g. /dev/spidev3.0) working
> in the slave mode (like NXP's dspi driver for Vybrid SoC).
Please do not submit new versions of already applied patches, please
submit incremental updates to the existing code. Modifying existing
commits creates problems for other users building on top of those
commits so it's best practice to only change pubished git commits if
absolutely essential.
That said I'll handle this this one time.
Hi Mark,
> On Wed, Sep 25, 2019 at 11:11:42AM +0200, Lukasz Majewski wrote:
> > This change is necessary for spidev devices (e.g. /dev/spidev3.0)
> > working in the slave mode (like NXP's dspi driver for Vybrid SoC).
>
> Please do not submit new versions of already applied patches, please
> submit incremental updates to the existing code. Modifying existing
> commits creates problems for other users building on top of those
> commits so it's best practice to only change pubished git commits if
> absolutely essential.
>
> That said I'll handle this this one time.
Thanks for help (and patience).
Best regards,
Lukasz Majewski
--
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