From: Charles Keepax ckeepax@opensource.cirrus.com
[ Upstream commit 0e793ba77c18382f08e440260fe72bc6fce2a3cb ]
Currently, the SPI core doesn't set the struct device fwnode pointer when it creates a new SPI device. This means when the device is registered the fwnode is NULL and the check in device_add which sets the fwnode->dev pointer is skipped. This wasn't previously an issue, however these two patches:
commit 4731210c09f5 ("gpiolib: Bind gpio_device to a driver to enable fw_devlink=on by default") commit ced2af419528 ("gpiolib: Don't probe gpio_device if it's not the primary device")
Added some code to the GPIO core which relies on using that fwnode->dev pointer to determine if a driver is bound to the fwnode and if not bind a stub GPIO driver. This means the GPIO providers behind SPI will get both the expected driver and this stub driver causing the stub driver to fail if it attempts to request any pin configuration. For example on my system:
madera-pinctrl madera-pinctrl: pin gpio5 already requested by madera-pinctrl; cannot claim for gpiochip3 madera-pinctrl madera-pinctrl: pin-4 (gpiochip3) status -22 madera-pinctrl madera-pinctrl: could not request pin 4 (gpio5) from group aif1 on device madera-pinctrl gpio_stub_drv gpiochip3: Error applying setting, reverse things back gpio_stub_drv: probe of gpiochip3 failed with error -22
The firmware node on the device created by the GPIO framework is set through the of_node pointer hence things generally actually work, however that fwnode->dev is never set, as the check was skipped at device_add time. This fix appears to match how the I2C subsystem handles the same situation.
Signed-off-by: Charles Keepax ckeepax@opensource.cirrus.com Link: https://lore.kernel.org/r/20210421101402.8468-1-ckeepax@opensource.cirrus.co... Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/spi/spi.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 0cf67de741e7..bd8b1f79dce2 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -2050,6 +2050,7 @@ of_register_spi_device(struct spi_controller *ctlr, struct device_node *nc) /* Store a pointer to the node in the device structure */ of_node_get(nc); spi->dev.of_node = nc; + spi->dev.fwnode = of_fwnode_handle(nc);
/* Register the new device */ rc = spi_add_device(spi);