[PATCH v2 2/4] video: backlight: lp855x: get PWM for PWM mode during probe

Artur Weber
2023-05-19T18:09:33Z

Also deprecate the pwm-period DT property, as it is now redundant
(pwms property already contains period value).

Signed-off-by: Artur Weber <aweber.kernel@gmail.com>
---
drivers/video/backlight/lp855x_bl.c | 48 ++++++++++++++++-------------
1 file changed, 26 insertions(+), 22 deletions(-)

diff --git a/drivers/video/backlight/lp855x_bl.c b/drivers/video/backlight/lp855x_bl.c
index a57c9ef3b1cc..0ef850dd8e84 100644
--- a/drivers/video/backlight/lp855x_bl.c
+++ b/drivers/video/backlight/lp855x_bl.c
@@ -218,23 +218,10 @@ static int lp855x_configure(struct lp855x *lp)

static void lp855x_pwm_ctrl(struct lp855x *lp, int br, int max_br)
{
- struct pwm_device *pwm;
struct pwm_state state;

- /* request pwm device with the consumer name */
- if (!lp->pwm) {
- pwm = devm_pwm_get(lp->dev, lp->chipname);
- if (IS_ERR(pwm))
- return;
-
- lp->pwm = pwm;
-
- pwm_init_state(lp->pwm, &state);
- } else {
- pwm_get_state(lp->pwm, &state);
- }
+ pwm_get_state(lp->pwm, &state);

- state.period = lp->pdata->period_ns;
state.duty_cycle = div_u64(br * state.period, max_br);
state.enabled = state.duty_cycle;

@@ -339,6 +326,7 @@ static int lp855x_parse_dt(struct lp855x *lp)
of_property_read_string(node, "bl-name", &pdata->name);
of_property_read_u8(node, "dev-ctrl", &pdata->device_control);
of_property_read_u8(node, "init-brt", &pdata->initial_brightness);
+ /* Deprecated, specify period in pwms property instead */
of_property_read_u32(node, "pwm-period", &pdata->period_ns);

/* Fill ROM platform data if defined */
@@ -399,6 +387,7 @@ static int lp855x_probe(struct i2c_client *cl)
const struct i2c_device_id *id = i2c_client_get_device_id(cl);
const struct acpi_device_id *acpi_id = NULL;
struct device *dev = &cl->dev;
+ struct pwm_state pwmstate;
struct lp855x *lp;
int ret;

@@ -457,11 +446,6 @@ static int lp855x_probe(struct i2c_client *cl)
}
}

- if (lp->pdata->period_ns > 0)
- lp->mode = PWM_BASED;
- else
- lp->mode = REGISTER_BASED;
-
lp->supply = devm_regulator_get(dev, "power");
if (IS_ERR(lp->supply)) {
if (PTR_ERR(lp->supply) == -EPROBE_DEFER)
@@ -472,11 +456,31 @@ static int lp855x_probe(struct i2c_client *cl)
lp->enable = devm_regulator_get_optional(dev, "enable");
if (IS_ERR(lp->enable)) {
ret = PTR_ERR(lp->enable);
- if (ret == -ENODEV) {
+ if (ret == -ENODEV)
lp->enable = NULL;
- } else {
+ else
return dev_err_probe(dev, ret, "getting enable regulator\n");
- }
+ }
+
+ lp->pwm = devm_pwm_get(lp->dev, lp->chipname);
+ if (IS_ERR(lp->pwm)) {
+ ret = PTR_ERR(lp->pwm);
+ if (ret == -ENODEV || ret == -EINVAL)
+ lp->pwm = NULL;
+ else
+ return dev_err_probe(dev, ret, "getting PWM\n");
+
+ lp->mode = REGISTER_BASED;
+ dev_dbg(dev, "mode: register based\n");
+ } else {
+ pwm_init_state(lp->pwm, &pwmstate);
+ /* Legacy platform data compatibility */
+ if (lp->pdata->period_ns > 0)
+ pwmstate.period = lp->pdata->period_ns;
+ pwm_apply_state(lp->pwm, &pwmstate);
+
+ lp->mode = PWM_BASED;
+ dev_dbg(dev, "mode: PWM based\n");
}

if (lp->supply) {
--
2.40.1