linux/drivers/leds/leds-dac124s085.c
Uwe Kleine-König a0386bba70
spi: make remove callback a void function
The value returned by an spi driver's remove function is mostly ignored.
(Only an error message is printed if the value is non-zero that the
error is ignored.)

So change the prototype of the remove function to return no value. This
way driver authors are not tempted to assume that passing an error to
the upper layer is a good idea. All drivers are adapted accordingly.
There is no intended change of behaviour, all callbacks were prepared to
return 0 before.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Claudius Heine <ch@denx.de>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC
Acked-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Acked-by: Łukasz Stelmach <l.stelmach@samsung.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20220123175201.34839-6-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
2022-02-09 13:00:45 +00:00

111 lines
2.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright 2008
* Guennadi Liakhovetski, DENX Software Engineering, <lg@denx.de>
*
* LED driver for the DAC124S085 SPI DAC
*/
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>
struct dac124s085_led {
struct led_classdev ldev;
struct spi_device *spi;
int id;
char name[sizeof("dac124s085-3")];
struct mutex mutex;
};
struct dac124s085 {
struct dac124s085_led leds[4];
};
#define REG_WRITE (0 << 12)
#define REG_WRITE_UPDATE (1 << 12)
#define ALL_WRITE_UPDATE (2 << 12)
#define POWER_DOWN_OUTPUT (3 << 12)
static int dac124s085_set_brightness(struct led_classdev *ldev,
enum led_brightness brightness)
{
struct dac124s085_led *led = container_of(ldev, struct dac124s085_led,
ldev);
u16 word;
int ret;
mutex_lock(&led->mutex);
word = cpu_to_le16(((led->id) << 14) | REG_WRITE_UPDATE |
(brightness & 0xfff));
ret = spi_write(led->spi, (const u8 *)&word, sizeof(word));
mutex_unlock(&led->mutex);
return ret;
}
static int dac124s085_probe(struct spi_device *spi)
{
struct dac124s085 *dac;
struct dac124s085_led *led;
int i, ret;
dac = devm_kzalloc(&spi->dev, sizeof(*dac), GFP_KERNEL);
if (!dac)
return -ENOMEM;
spi->bits_per_word = 16;
for (i = 0; i < ARRAY_SIZE(dac->leds); i++) {
led = dac->leds + i;
led->id = i;
led->spi = spi;
snprintf(led->name, sizeof(led->name), "dac124s085-%d", i);
mutex_init(&led->mutex);
led->ldev.name = led->name;
led->ldev.brightness = LED_OFF;
led->ldev.max_brightness = 0xfff;
led->ldev.brightness_set_blocking = dac124s085_set_brightness;
ret = led_classdev_register(&spi->dev, &led->ldev);
if (ret < 0)
goto eledcr;
}
spi_set_drvdata(spi, dac);
return 0;
eledcr:
while (i--)
led_classdev_unregister(&dac->leds[i].ldev);
return ret;
}
static void dac124s085_remove(struct spi_device *spi)
{
struct dac124s085 *dac = spi_get_drvdata(spi);
int i;
for (i = 0; i < ARRAY_SIZE(dac->leds); i++)
led_classdev_unregister(&dac->leds[i].ldev);
}
static struct spi_driver dac124s085_driver = {
.probe = dac124s085_probe,
.remove = dac124s085_remove,
.driver = {
.name = "dac124s085",
},
};
module_spi_driver(dac124s085_driver);
MODULE_AUTHOR("Guennadi Liakhovetski <lg@denx.de>");
MODULE_DESCRIPTION("DAC124S085 LED driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("spi:dac124s085");