[ Upstream commit 6ece49c56965544262523dae4a071ace3db63507 ]
Enabling the SPI CS35L41 audio codec driver for Steam Deck [1]
revealed a problem with the current AMD SPI controller driver
implementation, consisting of an unrecoverable system hang.
The issue can be prevented if we ensure the max transfer size
and the max message size do not exceed the FIFO buffer size.
According to the implementation of the downstream driver, the
AMD SPI controller is not able to handle more than 70 bytes per
transfer, which corresponds to the size of the FIFO buffer.
Hence, let's fix this by setting the SPI limits mentioned above.
[1] https://lore.kernel.org/r/20220621213819.262537-1-cristian.ciocaltea@collabora.com
Reported-by: Anastasios Vacharakis <vacharakis@o2mail.de>
Fixes: bbb336f39e ("spi: spi-amd: Add AMD SPI controller driver support")
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Link: https://lore.kernel.org/r/20220706100626.1234731-2-cristian.ciocaltea@collabora.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Since ACPI_PTR() is used to NULLify the value when !CONFIG_ACPI,
struct 'spi_acpi_match' becomes defined but unused.
Fixes the following W=1 kernel build warning(s):
drivers/spi/spi-amd.c:297:36: warning: ‘spi_acpi_match’ defined but not used [-Wunused-const-variable=]
297 | static const struct acpi_device_id spi_acpi_match[] = {
| ^~~~~~~~~~~~~~
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Cc: Sanjay R Mehta <sanju.mehta@amd.com>
Link: https://lore.kernel.org/r/20200717135424.2442271-15-lee.jones@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The AMD SPI driver calls spi_master_put() in its ->remove() hook even
though the preceding call to spi_unregister_master() already drops a
ref, thus leading to a refcount underflow. Drop the superfluous call
to spi_master_put().
This only leaves the call to spi_unregister_master() in the ->remove()
hook, so it's safe to change the ->probe() hook to use the devm version
of spi_register_master() and drop the ->remove() hook altogether.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/5e53ccdf1eecd4e015dba99d0d77389107f8a2e3.1588590210.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
