linux/drivers/leds/leds-sgm3140.c
Krzysztof Kozlowski 4582e783a2 leds: sgm3140: Simplify with dev_err_probe()
Common pattern of handling deferred probe can be simplified with
dev_err_probe().  Less code and also it prints the error value.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2020-09-09 11:20:09 +02:00

312 lines
7.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2020 Luca Weiss <luca@z3ntu.xyz>
#include <linux/gpio/consumer.h>
#include <linux/led-class-flash.h>
#include <linux/module.h>
#include <linux/regulator/consumer.h>
#include <linux/platform_device.h>
#include <media/v4l2-flash-led-class.h>
#define FLASH_TIMEOUT_DEFAULT 250000U /* 250ms */
#define FLASH_MAX_TIMEOUT_DEFAULT 300000U /* 300ms */
struct sgm3140 {
struct led_classdev_flash fled_cdev;
struct v4l2_flash *v4l2_flash;
struct timer_list powerdown_timer;
struct gpio_desc *flash_gpio;
struct gpio_desc *enable_gpio;
struct regulator *vin_regulator;
bool enabled;
/* current timeout in us */
u32 timeout;
/* maximum timeout in us */
u32 max_timeout;
};
static struct sgm3140 *flcdev_to_sgm3140(struct led_classdev_flash *flcdev)
{
return container_of(flcdev, struct sgm3140, fled_cdev);
}
static int sgm3140_strobe_set(struct led_classdev_flash *fled_cdev, bool state)
{
struct sgm3140 *priv = flcdev_to_sgm3140(fled_cdev);
int ret;
if (priv->enabled == state)
return 0;
if (state) {
ret = regulator_enable(priv->vin_regulator);
if (ret) {
dev_err(fled_cdev->led_cdev.dev,
"failed to enable regulator: %d\n", ret);
return ret;
}
gpiod_set_value_cansleep(priv->flash_gpio, 1);
gpiod_set_value_cansleep(priv->enable_gpio, 1);
mod_timer(&priv->powerdown_timer,
jiffies + usecs_to_jiffies(priv->timeout));
} else {
del_timer_sync(&priv->powerdown_timer);
gpiod_set_value_cansleep(priv->enable_gpio, 0);
gpiod_set_value_cansleep(priv->flash_gpio, 0);
ret = regulator_disable(priv->vin_regulator);
if (ret) {
dev_err(fled_cdev->led_cdev.dev,
"failed to disable regulator: %d\n", ret);
return ret;
}
}
priv->enabled = state;
return 0;
}
static int sgm3140_strobe_get(struct led_classdev_flash *fled_cdev, bool *state)
{
struct sgm3140 *priv = flcdev_to_sgm3140(fled_cdev);
*state = timer_pending(&priv->powerdown_timer);
return 0;
}
static int sgm3140_timeout_set(struct led_classdev_flash *fled_cdev,
u32 timeout)
{
struct sgm3140 *priv = flcdev_to_sgm3140(fled_cdev);
priv->timeout = timeout;
return 0;
}
static const struct led_flash_ops sgm3140_flash_ops = {
.strobe_set = sgm3140_strobe_set,
.strobe_get = sgm3140_strobe_get,
.timeout_set = sgm3140_timeout_set,
};
static int sgm3140_brightness_set(struct led_classdev *led_cdev,
enum led_brightness brightness)
{
struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
struct sgm3140 *priv = flcdev_to_sgm3140(fled_cdev);
bool enable = brightness == LED_ON;
int ret;
if (priv->enabled == enable)
return 0;
if (enable) {
ret = regulator_enable(priv->vin_regulator);
if (ret) {
dev_err(led_cdev->dev,
"failed to enable regulator: %d\n", ret);
return ret;
}
gpiod_set_value_cansleep(priv->enable_gpio, 1);
} else {
gpiod_set_value_cansleep(priv->enable_gpio, 0);
ret = regulator_disable(priv->vin_regulator);
if (ret) {
dev_err(led_cdev->dev,
"failed to disable regulator: %d\n", ret);
return ret;
}
}
priv->enabled = enable;
return 0;
}
static void sgm3140_powerdown_timer(struct timer_list *t)
{
struct sgm3140 *priv = from_timer(priv, t, powerdown_timer);
gpiod_set_value(priv->enable_gpio, 0);
gpiod_set_value(priv->flash_gpio, 0);
regulator_disable(priv->vin_regulator);
priv->enabled = false;
}
static void sgm3140_init_flash_timeout(struct sgm3140 *priv)
{
struct led_classdev_flash *fled_cdev = &priv->fled_cdev;
struct led_flash_setting *s;
/* Init flash timeout setting */
s = &fled_cdev->timeout;
s->min = 1;
s->max = priv->max_timeout;
s->step = 1;
s->val = FLASH_TIMEOUT_DEFAULT;
}
#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
static void sgm3140_init_v4l2_flash_config(struct sgm3140 *priv,
struct v4l2_flash_config *v4l2_sd_cfg)
{
struct led_classdev *led_cdev = &priv->fled_cdev.led_cdev;
struct led_flash_setting *s;
strscpy(v4l2_sd_cfg->dev_name, led_cdev->dev->kobj.name,
sizeof(v4l2_sd_cfg->dev_name));
/* Init flash intensity setting */
s = &v4l2_sd_cfg->intensity;
s->min = 0;
s->max = 1;
s->step = 1;
s->val = 1;
}
#else
static void sgm3140_init_v4l2_flash_config(struct sgm3140 *priv,
struct v4l2_flash_config *v4l2_sd_cfg)
{
}
#endif
static int sgm3140_probe(struct platform_device *pdev)
{
struct sgm3140 *priv;
struct led_classdev *led_cdev;
struct led_classdev_flash *fled_cdev;
struct led_init_data init_data = {};
struct fwnode_handle *child_node;
struct v4l2_flash_config v4l2_sd_cfg = {};
int ret;
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->flash_gpio = devm_gpiod_get(&pdev->dev, "flash", GPIOD_OUT_LOW);
ret = PTR_ERR_OR_ZERO(priv->flash_gpio);
if (ret)
return dev_err_probe(&pdev->dev, ret,
"Failed to request flash gpio\n");
priv->enable_gpio = devm_gpiod_get(&pdev->dev, "enable", GPIOD_OUT_LOW);
ret = PTR_ERR_OR_ZERO(priv->enable_gpio);
if (ret)
return dev_err_probe(&pdev->dev, ret,
"Failed to request enable gpio\n");
priv->vin_regulator = devm_regulator_get(&pdev->dev, "vin");
ret = PTR_ERR_OR_ZERO(priv->vin_regulator);
if (ret)
return dev_err_probe(&pdev->dev, ret,
"Failed to request regulator\n");
child_node = fwnode_get_next_available_child_node(pdev->dev.fwnode,
NULL);
if (!child_node) {
dev_err(&pdev->dev,
"No fwnode child node found for connected LED.\n");
return -EINVAL;
}
ret = fwnode_property_read_u32(child_node, "flash-max-timeout-us",
&priv->max_timeout);
if (ret) {
priv->max_timeout = FLASH_MAX_TIMEOUT_DEFAULT;
dev_warn(&pdev->dev,
"flash-max-timeout-us property missing\n");
}
/*
* Set default timeout to FLASH_DEFAULT_TIMEOUT except if max_timeout
* from DT is lower.
*/
priv->timeout = min(priv->max_timeout, FLASH_TIMEOUT_DEFAULT);
timer_setup(&priv->powerdown_timer, sgm3140_powerdown_timer, 0);
fled_cdev = &priv->fled_cdev;
led_cdev = &fled_cdev->led_cdev;
fled_cdev->ops = &sgm3140_flash_ops;
led_cdev->brightness_set_blocking = sgm3140_brightness_set;
led_cdev->max_brightness = LED_ON;
led_cdev->flags |= LED_DEV_CAP_FLASH;
sgm3140_init_flash_timeout(priv);
init_data.fwnode = child_node;
platform_set_drvdata(pdev, priv);
/* Register in the LED subsystem */
ret = devm_led_classdev_flash_register_ext(&pdev->dev,
fled_cdev, &init_data);
if (ret) {
dev_err(&pdev->dev, "Failed to register flash device: %d\n",
ret);
goto err;
}
sgm3140_init_v4l2_flash_config(priv, &v4l2_sd_cfg);
/* Create V4L2 Flash subdev */
priv->v4l2_flash = v4l2_flash_init(&pdev->dev,
child_node,
fled_cdev, NULL,
&v4l2_sd_cfg);
if (IS_ERR(priv->v4l2_flash)) {
ret = PTR_ERR(priv->v4l2_flash);
goto err;
}
return ret;
err:
fwnode_handle_put(child_node);
return ret;
}
static int sgm3140_remove(struct platform_device *pdev)
{
struct sgm3140 *priv = platform_get_drvdata(pdev);
del_timer_sync(&priv->powerdown_timer);
v4l2_flash_release(priv->v4l2_flash);
return 0;
}
static const struct of_device_id sgm3140_dt_match[] = {
{ .compatible = "sgmicro,sgm3140" },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, sgm3140_dt_match);
static struct platform_driver sgm3140_driver = {
.probe = sgm3140_probe,
.remove = sgm3140_remove,
.driver = {
.name = "sgm3140",
.of_match_table = sgm3140_dt_match,
},
};
module_platform_driver(sgm3140_driver);
MODULE_AUTHOR("Luca Weiss <luca@z3ntu.xyz>");
MODULE_DESCRIPTION("SG Micro SGM3140 charge pump LED driver");
MODULE_LICENSE("GPL v2");