diff options
Diffstat (limited to 'drivers/leds/flash/leds-sgm3140.c')
-rw-r--r-- | drivers/leds/flash/leds-sgm3140.c | 312 |
1 files changed, 312 insertions, 0 deletions
diff --git a/drivers/leds/flash/leds-sgm3140.c b/drivers/leds/flash/leds-sgm3140.c new file mode 100644 index 000000000..d3a30ad94 --- /dev/null +++ b/drivers/leds/flash/leds-sgm3140.c @@ -0,0 +1,312 @@ +// 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 = "ocs,ocp8110" }, + { .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"); |