static int backlight_pwm_of_probe(struct device_d *dev)
{
int ret;
struct pwm_backlight *pwm_backlight;
struct pwm_device *pwm;
pwm = of_pwm_request(dev->device_node, NULL);
if (IS_ERR(pwm)) {
dev_err(dev, "Cannot find PWM device\n");
return PTR_ERR(pwm);
}
pwm_backlight = xzalloc(sizeof(*pwm_backlight));
pwm_backlight->pwm = pwm;
pwm_backlight->period = pwm_get_period(pwm);
ret = pwm_backlight_parse_dt(dev, pwm_backlight);
if (ret)
return ret;
pwm_backlight->power = regulator_get(dev, "power");
if (IS_ERR(pwm_backlight->power)) {
dev_err(dev, "Cannot find regulator\n");
return PTR_ERR(pwm_backlight->power);
}
pwm_backlight->period = pwm_get_period(pwm_backlight->pwm);
pwm_backlight->backlight.brightness_set = backlight_pwm_set;
pwm_backlight->backlight.node = dev->device_node;
ret = backlight_register(&pwm_backlight->backlight);
if (ret)
return ret;
return 0;
}
static int pwm_backlight_probe(struct platform_device *pdev)
{
struct platform_pwm_backlight_data *data = dev_get_platdata(&pdev->dev);
struct platform_pwm_backlight_data defdata;
struct backlight_properties props;
struct backlight_device *bl;
struct pwm_bl_data *pb;
int ret;
if (!data) {
ret = pwm_backlight_parse_dt(&pdev->dev, &defdata);
if (ret < 0) {
dev_err(&pdev->dev, "failed to find platform data\n");
return ret;
}
data = &defdata;
}
if (data->init) {
ret = data->init(&pdev->dev);
if (ret < 0)
return ret;
}
pb = devm_kzalloc(&pdev->dev, sizeof(*pb), GFP_KERNEL);
if (!pb) {
ret = -ENOMEM;
goto err_alloc;
}
if (data->levels) {
unsigned int i;
for (i = 0; i <= data->max_brightness; i++)
if (data->levels[i] > pb->scale)
pb->scale = data->levels[i];
pb->levels = data->levels;
} else
pb->scale = data->max_brightness;
pb->enable_gpio = data->enable_gpio;
pb->enable_gpio_flags = data->enable_gpio_flags;
pb->notify = data->notify;
pb->notify_after = data->notify_after;
pb->check_fb = data->check_fb;
pb->exit = data->exit;
pb->dev = &pdev->dev;
pb->enabled = false;
if (gpio_is_valid(pb->enable_gpio)) {
unsigned long flags;
if (pb->enable_gpio_flags & PWM_BACKLIGHT_GPIO_ACTIVE_LOW)
flags = GPIOF_OUT_INIT_HIGH;
else
flags = GPIOF_OUT_INIT_LOW;
ret = gpio_request_one(pb->enable_gpio, flags, "enable");
if (ret < 0) {
dev_err(&pdev->dev, "failed to request GPIO#%d: %d\n",
pb->enable_gpio, ret);
goto err_alloc;
}
}
pb->power_supply = devm_regulator_get(&pdev->dev, "power");
if (IS_ERR(pb->power_supply)) {
ret = PTR_ERR(pb->power_supply);
goto err_gpio;
}
pb->pwm = devm_pwm_get(&pdev->dev, NULL);
if (IS_ERR(pb->pwm)) {
dev_err(&pdev->dev, "unable to request PWM, trying legacy API\n");
pb->pwm = pwm_request(data->pwm_id, "pwm-backlight");
if (IS_ERR(pb->pwm)) {
dev_err(&pdev->dev, "unable to request legacy PWM\n");
ret = PTR_ERR(pb->pwm);
goto err_gpio;
}
}
dev_dbg(&pdev->dev, "got pwm for backlight\n");
/*
* The DT case will set the pwm_period_ns field to 0 and store the
* period, parsed from the DT, in the PWM device. For the non-DT case,
* set the period from platform data.
*/
if (data->pwm_period_ns > 0)
pwm_set_period(pb->pwm, data->pwm_period_ns);
pb->period = pwm_get_period(pb->pwm);
pb->lth_brightness = data->lth_brightness * (pb->period / pb->scale);
memset(&props, 0, sizeof(struct backlight_properties));
props.type = BACKLIGHT_RAW;
props.max_brightness = data->max_brightness;
bl = backlight_device_register("lcd-bl", &pdev->dev, pb,
&pwm_backlight_ops, &props);
if (IS_ERR(bl)) {
dev_err(&pdev->dev, "failed to register backlight\n");
ret = PTR_ERR(bl);
goto err_gpio;
}
if (data->dft_brightness > data->max_brightness) {
dev_warn(&pdev->dev,
"invalid default brightness level: %u, using %u\n",
data->dft_brightness, data->max_brightness);
data->dft_brightness = data->max_brightness;
}
bl->props.brightness = data->dft_brightness;
backlight_update_status(bl);
platform_set_drvdata(pdev, bl);
return 0;
err_gpio:
if (gpio_is_valid(pb->enable_gpio))
gpio_free(pb->enable_gpio);
err_alloc:
if (data->exit)
data->exit(&pdev->dev);
return ret;
}
static int pwm_backlight_probe(struct platform_device *pdev)
{
struct platform_pwm_backlight_data *data = dev_get_platdata(&pdev->dev);
struct platform_pwm_backlight_data defdata;
struct backlight_properties props;
struct backlight_device *bl;
struct device_node *node = pdev->dev.of_node;
struct pwm_bl_data *pb;
struct pwm_state state;
unsigned int i;
int ret;
if (!data) {
ret = pwm_backlight_parse_dt(&pdev->dev, &defdata);
if (ret < 0) {
dev_err(&pdev->dev, "failed to find platform data\n");
return ret;
}
data = &defdata;
}
if (data->init) {
ret = data->init(&pdev->dev);
if (ret < 0)
return ret;
}
pb = devm_kzalloc(&pdev->dev, sizeof(*pb), GFP_KERNEL);
if (!pb) {
ret = -ENOMEM;
goto err_alloc;
}
pb->notify = data->notify;
pb->notify_after = data->notify_after;
pb->check_fb = data->check_fb;
pb->exit = data->exit;
pb->dev = &pdev->dev;
pb->enabled = false;
pb->post_pwm_on_delay = data->post_pwm_on_delay;
pb->pwm_off_delay = data->pwm_off_delay;
pb->enable_gpio = devm_gpiod_get_optional(&pdev->dev, "enable",
GPIOD_ASIS);
if (IS_ERR(pb->enable_gpio)) {
ret = PTR_ERR(pb->enable_gpio);
goto err_alloc;
}
/*
* Compatibility fallback for drivers still using the integer GPIO
* platform data. Must go away soon.
*/
if (!pb->enable_gpio && gpio_is_valid(data->enable_gpio)) {
ret = devm_gpio_request_one(&pdev->dev, data->enable_gpio,
GPIOF_OUT_INIT_HIGH, "enable");
if (ret < 0) {
dev_err(&pdev->dev, "failed to request GPIO#%d: %d\n",
data->enable_gpio, ret);
goto err_alloc;
}
pb->enable_gpio = gpio_to_desc(data->enable_gpio);
}
/*
* If the GPIO is not known to be already configured as output, that
* is, if gpiod_get_direction returns either 1 or -EINVAL, change the
* direction to output and set the GPIO as active.
* Do not force the GPIO to active when it was already output as it
* could cause backlight flickering or we would enable the backlight too
* early. Leave the decision of the initial backlight state for later.
*/
if (pb->enable_gpio &&
gpiod_get_direction(pb->enable_gpio) != 0)
gpiod_direction_output(pb->enable_gpio, 1);
pb->power_supply = devm_regulator_get(&pdev->dev, "power");
if (IS_ERR(pb->power_supply)) {
ret = PTR_ERR(pb->power_supply);
goto err_alloc;
}
pb->pwm = devm_pwm_get(&pdev->dev, NULL);
if (IS_ERR(pb->pwm) && PTR_ERR(pb->pwm) != -EPROBE_DEFER && !node) {
dev_err(&pdev->dev, "unable to request PWM, trying legacy API\n");
pb->legacy = true;
pb->pwm = pwm_request(data->pwm_id, "pwm-backlight");
}
if (IS_ERR(pb->pwm)) {
ret = PTR_ERR(pb->pwm);
if (ret != -EPROBE_DEFER)
dev_err(&pdev->dev, "unable to request PWM\n");
goto err_alloc;
}
dev_dbg(&pdev->dev, "got pwm for backlight\n");
/* Sync up PWM state. */
pwm_init_state(pb->pwm, &state);
/*
* The DT case will set the pwm_period_ns field to 0 and store the
* period, parsed from the DT, in the PWM device. For the non-DT case,
* set the period from platform data if it has not already been set
* via the PWM lookup table.
*/
if (!state.period && (data->pwm_period_ns > 0))
state.period = data->pwm_period_ns;
ret = pwm_apply_state(pb->pwm, &state);
if (ret) {
dev_err(&pdev->dev, "failed to apply initial PWM state: %d\n",
ret);
goto err_alloc;
}
if (data->levels) {
/*
* For the DT case, only when brightness levels is defined
* data->levels is filled. For the non-DT case, data->levels
* can come from platform data, however is not usual.
*/
for (i = 0; i <= data->max_brightness; i++) {
if (data->levels[i] > pb->scale)
pb->scale = data->levels[i];
pb->levels = data->levels;
}
} else if (!data->max_brightness) {
/*
* If no brightness levels are provided and max_brightness is
* not set, use the default brightness table. For the DT case,
* max_brightness is set to 0 when brightness levels is not
* specified. For the non-DT case, max_brightness is usually
* set to some value.
*/
/* Get the PWM period (in nanoseconds) */
pwm_get_state(pb->pwm, &state);
ret = pwm_backlight_brightness_default(&pdev->dev, data,
state.period);
if (ret < 0) {
dev_err(&pdev->dev,
"failed to setup default brightness table\n");
goto err_alloc;
}
for (i = 0; i <= data->max_brightness; i++) {
if (data->levels[i] > pb->scale)
pb->scale = data->levels[i];
pb->levels = data->levels;
}
} else {
/*
* That only happens for the non-DT case, where platform data
* sets the max_brightness value.
*/
pb->scale = data->max_brightness;
}
pb->lth_brightness = data->lth_brightness * (state.period / pb->scale);
memset(&props, 0, sizeof(struct backlight_properties));
props.type = BACKLIGHT_RAW;
props.max_brightness = data->max_brightness;
bl = backlight_device_register(dev_name(&pdev->dev), &pdev->dev, pb,
&pwm_backlight_ops, &props);
if (IS_ERR(bl)) {
dev_err(&pdev->dev, "failed to register backlight\n");
ret = PTR_ERR(bl);
if (pb->legacy)
pwm_free(pb->pwm);
goto err_alloc;
}
if (data->dft_brightness > data->max_brightness) {
dev_warn(&pdev->dev,
"invalid default brightness level: %u, using %u\n",
data->dft_brightness, data->max_brightness);
data->dft_brightness = data->max_brightness;
}
bl->props.brightness = data->dft_brightness;
bl->props.power = pwm_backlight_initial_power_state(pb);
backlight_update_status(bl);
platform_set_drvdata(pdev, bl);
return 0;
err_alloc:
if (data->exit)
data->exit(&pdev->dev);
return ret;
}
static int pwm_backlight_probe(struct platform_device *pdev)
{
struct platform_pwm_backlight_data *data = pdev->dev.platform_data;
struct platform_pwm_backlight_data defdata;
struct backlight_properties props;
struct backlight_device *bl;
struct pwm_bl_data *pb;
unsigned int max;
int ret;
if (!data) {
ret = pwm_backlight_parse_dt(&pdev->dev, &defdata);
if (ret < 0) {
dev_err(&pdev->dev, "failed to find platform data\n");
return ret;
}
data = &defdata;
}
if (data->init) {
ret = data->init(&pdev->dev);
if (ret < 0)
return ret;
}
pb = devm_kzalloc(&pdev->dev, sizeof(*pb), GFP_KERNEL);
if (!pb) {
dev_err(&pdev->dev, "no memory for state\n");
ret = -ENOMEM;
goto err_alloc;
}
if (data->levels) {
max = data->levels[data->max_brightness];
pb->levels = data->levels;
} else
max = data->max_brightness;
pb->notify = data->notify;
pb->notify_after = data->notify_after;
pb->check_fb = data->check_fb;
pb->exit = data->exit;
pb->dev = &pdev->dev;
pb->pwm = devm_pwm_get(&pdev->dev, NULL);
if (IS_ERR(pb->pwm)) {
dev_err(&pdev->dev, "unable to request PWM, trying legacy API\n");
pb->pwm = pwm_request(data->pwm_id, "pwm-backlight");
if (IS_ERR(pb->pwm)) {
dev_err(&pdev->dev, "unable to request legacy PWM\n");
ret = PTR_ERR(pb->pwm);
goto err_alloc;
}
}
dev_dbg(&pdev->dev, "got pwm for backlight\n");
/*
* The DT case will set the pwm_period_ns field to 0 and store the
* period, parsed from the DT, in the PWM device. For the non-DT case,
* set the period from platform data.
*/
if (data->pwm_period_ns > 0)
pwm_set_period(pb->pwm, data->pwm_period_ns);
pb->period = pwm_get_period(pb->pwm);
pb->lth_brightness = data->lth_brightness * (pb->period / max);
memset(&props, 0, sizeof(struct backlight_properties));
props.type = BACKLIGHT_RAW;
props.max_brightness = data->max_brightness;
bl = backlight_device_register(dev_name(&pdev->dev), &pdev->dev, pb,
&pwm_backlight_ops, &props);
if (IS_ERR(bl)) {
dev_err(&pdev->dev, "failed to register backlight\n");
ret = PTR_ERR(bl);
goto err_alloc;
}
if (data->dft_brightness > data->max_brightness) {
dev_warn(&pdev->dev,
"invalid default brightness level: %u, using %u\n",
data->dft_brightness, data->max_brightness);
data->dft_brightness = data->max_brightness;
}
bl->props.brightness = data->dft_brightness;
backlight_update_status(bl);
platform_set_drvdata(pdev, bl);
return 0;
err_alloc:
if (data->exit)
data->exit(&pdev->dev);
return ret;
}
