linux-hardened/drivers/leds/leds-aat1290.c
Uwe Kleine-König 8a687719d0 leds: aat1290: pass flags parameter to devm_gpiod_get
Since 39b2bbe3d7 (gpio: add flags argument to gpiod_get*() functions)
which appeared in v3.17-rc1, the gpiod_get* functions take an additional
parameter that allows to specify direction and initial value for output.

In this case the driver cannot easily be simplified but as the flags
parameter will become mandatory soon this change is necessary
beforehand.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>
2015-06-22 13:57:24 -07:00

576 lines
15 KiB
C

/*
* LED Flash class driver for the AAT1290
* 1.5A Step-Up Current Regulator for Flash LEDs
*
* Copyright (C) 2015, Samsung Electronics Co., Ltd.
* Author: Jacek Anaszewski <j.anaszewski@samsung.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*/
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/led-class-flash.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/workqueue.h>
#include <media/v4l2-flash-led-class.h>
#define AAT1290_MOVIE_MODE_CURRENT_ADDR 17
#define AAT1290_MAX_MM_CURR_PERCENT_0 16
#define AAT1290_MAX_MM_CURR_PERCENT_100 1
#define AAT1290_FLASH_SAFETY_TIMER_ADDR 18
#define AAT1290_MOVIE_MODE_CONFIG_ADDR 19
#define AAT1290_MOVIE_MODE_OFF 1
#define AAT1290_MOVIE_MODE_ON 3
#define AAT1290_MM_CURRENT_RATIO_ADDR 20
#define AAT1290_MM_TO_FL_1_92 1
#define AAT1290_MM_TO_FL_RATIO 1000 / 1920
#define AAT1290_MAX_MM_CURRENT(fl_max) (fl_max * AAT1290_MM_TO_FL_RATIO)
#define AAT1290_LATCH_TIME_MIN_US 500
#define AAT1290_LATCH_TIME_MAX_US 1000
#define AAT1290_EN_SET_TICK_TIME_US 1
#define AAT1290_FLEN_OFF_DELAY_TIME_US 10
#define AAT1290_FLASH_TM_NUM_LEVELS 16
#define AAT1290_MM_CURRENT_SCALE_SIZE 15
struct aat1290_led_config_data {
/* maximum LED current in movie mode */
u32 max_mm_current;
/* maximum LED current in flash mode */
u32 max_flash_current;
/* maximum flash timeout */
u32 max_flash_tm;
/* external strobe capability */
bool has_external_strobe;
/* max LED brightness level */
enum led_brightness max_brightness;
};
struct aat1290_led {
/* platform device data */
struct platform_device *pdev;
/* secures access to the device */
struct mutex lock;
/* corresponding LED Flash class device */
struct led_classdev_flash fled_cdev;
/* V4L2 Flash device */
struct v4l2_flash *v4l2_flash;
/* FLEN pin */
struct gpio_desc *gpio_fl_en;
/* EN|SET pin */
struct gpio_desc *gpio_en_set;
/* movie mode current scale */
int *mm_current_scale;
/* device mode */
bool movie_mode;
/* brightness cache */
unsigned int torch_brightness;
/* assures led-triggers compatibility */
struct work_struct work_brightness_set;
};
static struct aat1290_led *fled_cdev_to_led(
struct led_classdev_flash *fled_cdev)
{
return container_of(fled_cdev, struct aat1290_led, fled_cdev);
}
static void aat1290_as2cwire_write(struct aat1290_led *led, int addr, int value)
{
int i;
gpiod_direction_output(led->gpio_fl_en, 0);
gpiod_direction_output(led->gpio_en_set, 0);
udelay(AAT1290_FLEN_OFF_DELAY_TIME_US);
/* write address */
for (i = 0; i < addr; ++i) {
udelay(AAT1290_EN_SET_TICK_TIME_US);
gpiod_direction_output(led->gpio_en_set, 0);
udelay(AAT1290_EN_SET_TICK_TIME_US);
gpiod_direction_output(led->gpio_en_set, 1);
}
usleep_range(AAT1290_LATCH_TIME_MIN_US, AAT1290_LATCH_TIME_MAX_US);
/* write data */
for (i = 0; i < value; ++i) {
udelay(AAT1290_EN_SET_TICK_TIME_US);
gpiod_direction_output(led->gpio_en_set, 0);
udelay(AAT1290_EN_SET_TICK_TIME_US);
gpiod_direction_output(led->gpio_en_set, 1);
}
usleep_range(AAT1290_LATCH_TIME_MIN_US, AAT1290_LATCH_TIME_MAX_US);
}
static void aat1290_set_flash_safety_timer(struct aat1290_led *led,
unsigned int micro_sec)
{
struct led_classdev_flash *fled_cdev = &led->fled_cdev;
struct led_flash_setting *flash_tm = &fled_cdev->timeout;
int flash_tm_reg = AAT1290_FLASH_TM_NUM_LEVELS -
(micro_sec / flash_tm->step) + 1;
aat1290_as2cwire_write(led, AAT1290_FLASH_SAFETY_TIMER_ADDR,
flash_tm_reg);
}
static void aat1290_brightness_set(struct aat1290_led *led,
enum led_brightness brightness)
{
mutex_lock(&led->lock);
if (brightness == 0) {
gpiod_direction_output(led->gpio_fl_en, 0);
gpiod_direction_output(led->gpio_en_set, 0);
led->movie_mode = false;
} else {
if (!led->movie_mode) {
aat1290_as2cwire_write(led,
AAT1290_MM_CURRENT_RATIO_ADDR,
AAT1290_MM_TO_FL_1_92);
led->movie_mode = true;
}
aat1290_as2cwire_write(led, AAT1290_MOVIE_MODE_CURRENT_ADDR,
AAT1290_MAX_MM_CURR_PERCENT_0 - brightness);
aat1290_as2cwire_write(led, AAT1290_MOVIE_MODE_CONFIG_ADDR,
AAT1290_MOVIE_MODE_ON);
}
mutex_unlock(&led->lock);
}
/* LED subsystem callbacks */
static void aat1290_brightness_set_work(struct work_struct *work)
{
struct aat1290_led *led =
container_of(work, struct aat1290_led, work_brightness_set);
aat1290_brightness_set(led, led->torch_brightness);
}
static void aat1290_led_brightness_set(struct led_classdev *led_cdev,
enum led_brightness brightness)
{
struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
led->torch_brightness = brightness;
schedule_work(&led->work_brightness_set);
}
static int aat1290_led_brightness_set_sync(struct led_classdev *led_cdev,
enum led_brightness brightness)
{
struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
aat1290_brightness_set(led, brightness);
return 0;
}
static int aat1290_led_flash_strobe_set(struct led_classdev_flash *fled_cdev,
bool state)
{
struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
struct led_classdev *led_cdev = &fled_cdev->led_cdev;
struct led_flash_setting *timeout = &fled_cdev->timeout;
mutex_lock(&led->lock);
if (state) {
aat1290_set_flash_safety_timer(led, timeout->val);
gpiod_direction_output(led->gpio_fl_en, 1);
} else {
gpiod_direction_output(led->gpio_fl_en, 0);
gpiod_direction_output(led->gpio_en_set, 0);
}
/*
* To reenter movie mode after a flash event the part must be cycled
* off and back on to reset the movie mode and reprogrammed via the
* AS2Cwire. Therefore the brightness and movie_mode properties needs
* to be updated here to reflect the actual state.
*/
led_cdev->brightness = 0;
led->movie_mode = false;
mutex_unlock(&led->lock);
return 0;
}
static int aat1290_led_flash_timeout_set(struct led_classdev_flash *fled_cdev,
u32 timeout)
{
/*
* Don't do anything - flash timeout is cached in the led-class-flash
* core and will be applied in the strobe_set op, as writing the
* safety timer register spuriously turns the torch mode on.
*/
return 0;
}
static int aat1290_led_parse_dt(struct aat1290_led *led,
struct aat1290_led_config_data *cfg,
struct device_node **sub_node)
{
struct led_classdev *led_cdev = &led->fled_cdev.led_cdev;
struct device *dev = &led->pdev->dev;
struct device_node *child_node;
#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
struct pinctrl *pinctrl;
#endif
int ret = 0;
led->gpio_fl_en = devm_gpiod_get(dev, "flen", GPIOD_ASIS);
if (IS_ERR(led->gpio_fl_en)) {
ret = PTR_ERR(led->gpio_fl_en);
dev_err(dev, "Unable to claim gpio \"flen\".\n");
return ret;
}
led->gpio_en_set = devm_gpiod_get(dev, "enset", GPIOD_ASIS);
if (IS_ERR(led->gpio_en_set)) {
ret = PTR_ERR(led->gpio_en_set);
dev_err(dev, "Unable to claim gpio \"enset\".\n");
return ret;
}
#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
pinctrl = devm_pinctrl_get_select_default(&led->pdev->dev);
if (IS_ERR(pinctrl)) {
cfg->has_external_strobe = false;
dev_info(dev,
"No support for external strobe detected.\n");
} else {
cfg->has_external_strobe = true;
}
#endif
child_node = of_get_next_available_child(dev->of_node, NULL);
if (!child_node) {
dev_err(dev, "No DT child node found for connected LED.\n");
return -EINVAL;
}
led_cdev->name = of_get_property(child_node, "label", NULL) ? :
child_node->name;
ret = of_property_read_u32(child_node, "led-max-microamp",
&cfg->max_mm_current);
/*
* led-max-microamp will default to 1/20 of flash-max-microamp
* in case it is missing.
*/
if (ret < 0)
dev_warn(dev,
"led-max-microamp DT property missing\n");
ret = of_property_read_u32(child_node, "flash-max-microamp",
&cfg->max_flash_current);
if (ret < 0) {
dev_err(dev,
"flash-max-microamp DT property missing\n");
return ret;
}
ret = of_property_read_u32(child_node, "flash-max-timeout-us",
&cfg->max_flash_tm);
if (ret < 0) {
dev_err(dev,
"flash-max-timeout-us DT property missing\n");
return ret;
}
of_node_put(child_node);
*sub_node = child_node;
return ret;
}
static void aat1290_led_validate_mm_current(struct aat1290_led *led,
struct aat1290_led_config_data *cfg)
{
int i, b = 0, e = AAT1290_MM_CURRENT_SCALE_SIZE;
while (e - b > 1) {
i = b + (e - b) / 2;
if (cfg->max_mm_current < led->mm_current_scale[i])
e = i;
else
b = i;
}
cfg->max_mm_current = led->mm_current_scale[b];
cfg->max_brightness = b + 1;
}
int init_mm_current_scale(struct aat1290_led *led,
struct aat1290_led_config_data *cfg)
{
int max_mm_current_percent[] = { 20, 22, 25, 28, 32, 36, 40, 45, 50, 56,
63, 71, 79, 89, 100 };
int i, max_mm_current =
AAT1290_MAX_MM_CURRENT(cfg->max_flash_current);
led->mm_current_scale = devm_kzalloc(&led->pdev->dev,
sizeof(max_mm_current_percent),
GFP_KERNEL);
if (!led->mm_current_scale)
return -ENOMEM;
for (i = 0; i < AAT1290_MM_CURRENT_SCALE_SIZE; ++i)
led->mm_current_scale[i] = max_mm_current *
max_mm_current_percent[i] / 100;
return 0;
}
static int aat1290_led_get_configuration(struct aat1290_led *led,
struct aat1290_led_config_data *cfg,
struct device_node **sub_node)
{
int ret;
ret = aat1290_led_parse_dt(led, cfg, sub_node);
if (ret < 0)
return ret;
/*
* Init non-linear movie mode current scale basing
* on the max flash current from led configuration.
*/
ret = init_mm_current_scale(led, cfg);
if (ret < 0)
return ret;
aat1290_led_validate_mm_current(led, cfg);
#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
#else
devm_kfree(&led->pdev->dev, led->mm_current_scale);
#endif
return 0;
}
static void aat1290_init_flash_timeout(struct aat1290_led *led,
struct aat1290_led_config_data *cfg)
{
struct led_classdev_flash *fled_cdev = &led->fled_cdev;
struct led_flash_setting *setting;
/* Init flash timeout setting */
setting = &fled_cdev->timeout;
setting->min = cfg->max_flash_tm / AAT1290_FLASH_TM_NUM_LEVELS;
setting->max = cfg->max_flash_tm;
setting->step = setting->min;
setting->val = setting->max;
}
#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
static enum led_brightness aat1290_intensity_to_brightness(
struct v4l2_flash *v4l2_flash,
s32 intensity)
{
struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
int i;
for (i = AAT1290_MM_CURRENT_SCALE_SIZE - 1; i >= 0; --i)
if (intensity >= led->mm_current_scale[i])
return i + 1;
return 1;
}
static s32 aat1290_brightness_to_intensity(struct v4l2_flash *v4l2_flash,
enum led_brightness brightness)
{
struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
return led->mm_current_scale[brightness - 1];
}
static int aat1290_led_external_strobe_set(struct v4l2_flash *v4l2_flash,
bool enable)
{
struct aat1290_led *led = fled_cdev_to_led(v4l2_flash->fled_cdev);
struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
struct led_classdev *led_cdev = &fled_cdev->led_cdev;
struct pinctrl *pinctrl;
gpiod_direction_output(led->gpio_fl_en, 0);
gpiod_direction_output(led->gpio_en_set, 0);
led->movie_mode = false;
led_cdev->brightness = 0;
pinctrl = devm_pinctrl_get_select(&led->pdev->dev,
enable ? "isp" : "host");
if (IS_ERR(pinctrl)) {
dev_warn(&led->pdev->dev, "Unable to switch strobe source.\n");
return PTR_ERR(pinctrl);
}
return 0;
}
static void aat1290_init_v4l2_flash_config(struct aat1290_led *led,
struct aat1290_led_config_data *led_cfg,
struct v4l2_flash_config *v4l2_sd_cfg)
{
struct led_classdev *led_cdev = &led->fled_cdev.led_cdev;
struct led_flash_setting *s;
strlcpy(v4l2_sd_cfg->dev_name, led_cdev->name,
sizeof(v4l2_sd_cfg->dev_name));
s = &v4l2_sd_cfg->torch_intensity;
s->min = led->mm_current_scale[0];
s->max = led_cfg->max_mm_current;
s->step = 1;
s->val = s->max;
v4l2_sd_cfg->has_external_strobe = led_cfg->has_external_strobe;
}
static const struct v4l2_flash_ops v4l2_flash_ops = {
.external_strobe_set = aat1290_led_external_strobe_set,
.intensity_to_led_brightness = aat1290_intensity_to_brightness,
.led_brightness_to_intensity = aat1290_brightness_to_intensity,
};
#else
static inline void aat1290_init_v4l2_flash_config(struct aat1290_led *led,
struct aat1290_led_config_data *led_cfg,
struct v4l2_flash_config *v4l2_sd_cfg)
{
}
static const struct v4l2_flash_ops v4l2_flash_ops;
#endif
static const struct led_flash_ops flash_ops = {
.strobe_set = aat1290_led_flash_strobe_set,
.timeout_set = aat1290_led_flash_timeout_set,
};
static int aat1290_led_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *sub_node = NULL;
struct aat1290_led *led;
struct led_classdev *led_cdev;
struct led_classdev_flash *fled_cdev;
struct aat1290_led_config_data led_cfg = {};
struct v4l2_flash_config v4l2_sd_cfg = {};
int ret;
led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
if (!led)
return -ENOMEM;
led->pdev = pdev;
platform_set_drvdata(pdev, led);
fled_cdev = &led->fled_cdev;
fled_cdev->ops = &flash_ops;
led_cdev = &fled_cdev->led_cdev;
ret = aat1290_led_get_configuration(led, &led_cfg, &sub_node);
if (ret < 0)
return ret;
mutex_init(&led->lock);
/* Initialize LED Flash class device */
led_cdev->brightness_set = aat1290_led_brightness_set;
led_cdev->brightness_set_sync = aat1290_led_brightness_set_sync;
led_cdev->max_brightness = led_cfg.max_brightness;
led_cdev->flags |= LED_DEV_CAP_FLASH;
INIT_WORK(&led->work_brightness_set, aat1290_brightness_set_work);
aat1290_init_flash_timeout(led, &led_cfg);
/* Register LED Flash class device */
ret = led_classdev_flash_register(&pdev->dev, fled_cdev);
if (ret < 0)
goto err_flash_register;
aat1290_init_v4l2_flash_config(led, &led_cfg, &v4l2_sd_cfg);
/* Create V4L2 Flash subdev. */
led->v4l2_flash = v4l2_flash_init(dev, sub_node, fled_cdev, NULL,
&v4l2_flash_ops, &v4l2_sd_cfg);
if (IS_ERR(led->v4l2_flash)) {
ret = PTR_ERR(led->v4l2_flash);
goto error_v4l2_flash_init;
}
return 0;
error_v4l2_flash_init:
led_classdev_flash_unregister(fled_cdev);
err_flash_register:
mutex_destroy(&led->lock);
return ret;
}
static int aat1290_led_remove(struct platform_device *pdev)
{
struct aat1290_led *led = platform_get_drvdata(pdev);
v4l2_flash_release(led->v4l2_flash);
led_classdev_flash_unregister(&led->fled_cdev);
cancel_work_sync(&led->work_brightness_set);
mutex_destroy(&led->lock);
return 0;
}
static const struct of_device_id aat1290_led_dt_match[] = {
{ .compatible = "skyworks,aat1290" },
{},
};
static struct platform_driver aat1290_led_driver = {
.probe = aat1290_led_probe,
.remove = aat1290_led_remove,
.driver = {
.name = "aat1290",
.of_match_table = aat1290_led_dt_match,
},
};
module_platform_driver(aat1290_led_driver);
MODULE_AUTHOR("Jacek Anaszewski <j.anaszewski@samsung.com>");
MODULE_DESCRIPTION("Skyworks Current Regulator for Flash LEDs");
MODULE_LICENSE("GPL v2");