Commit 19368f0f authored by Krzysztof Kozlowski's avatar Krzysztof Kozlowski Committed by Greg Kroah-Hartman
Browse files

spi: Use helper for safer setting of driver_override 



Use a helper to set driver_override to the reduce amount of duplicated
code.

Reviewed-by: default avatarMark Brown <broonie@kernel.org>
Signed-off-by: default avatarKrzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220419113435.246203-8-krzysztof.kozlowski@linaro.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 1e8ee512

drivers/spi/spi.c

+4 −22
Original line number Diff line number Diff line
@@ -71,29 +71,11 @@ static ssize_t driver_override_store(struct device *dev, 
				     const char *buf, size_t count)

{

	struct spi_device *spi = to_spi_device(dev);

	const char *end = memchr(buf, '\n', count);

	const size_t len = end ? end - buf : count;

	const char *driver_override, *old;



	/* We need to keep extra room for a newline when displaying value */

	if (len >= (PAGE_SIZE - 1))

		return -EINVAL;



	driver_override = kstrndup(buf, len, GFP_KERNEL);

	if (!driver_override)

		return -ENOMEM;

	int ret;



	device_lock(dev);

	old = spi->driver_override;

	if (len) {

		spi->driver_override = driver_override;

	} else {

		/* Empty string, disable driver override */

		spi->driver_override = NULL;

		kfree(driver_override);

	}

	device_unlock(dev);

	kfree(old);

	ret = driver_set_override(dev, &spi->driver_override, buf, count);

	if (ret)

		return ret;



	return count;

}

include/linux/spi/spi.h

+2 −0
Original line number Diff line number Diff line
@@ -138,6 +138,8 @@ extern int spi_delay_exec(struct spi_delay *_delay, struct spi_transfer *xfer); 
 *	for driver coldplugging, and in uevents used for hotplugging

 * @driver_override: If the name of a driver is written to this attribute, then

 *	the device will bind to the named driver and only the named driver.

 *	Do not set directly, because core frees it; use driver_set_override() to

 *	set or clear it.

 * @cs_gpiod: gpio descriptor of the chipselect line (optional, NULL when

 *	not using a GPIO line)

 * @word_delay: delay to be inserted between consecutive