This comment serves as an example how led controller drivers
could be simplified if led-class/led-core would handle DT node
locating and parsing. leds-lm3692x was randomly selected from
drivers using 'devm_led_classdev_register_ext' API. No further
study was done :)
This commit HAS NOT BEEN TESTED at all. Only compile tested.
This is only RFC - Eg, request for comments. If people see some
of the ideas as useful then properly tested patch should be
provided.
Signed-off-by: Matti Vaittinen <matti.vaittinen@xxxxxxxxxxxxxxxxx>
---
drivers/leds/leds-lm3692x.c | 75 ++++++++++++++++++++-----------------
1 file changed, 41 insertions(+), 34 deletions(-)
diff --git a/drivers/leds/leds-lm3692x.c b/drivers/leds/leds-lm3692x.c
index 3d381f2f73d0..abe2b1113049 100644
--- a/drivers/leds/leds-lm3692x.c
+++ b/drivers/leds/leds-lm3692x.c
@@ -108,7 +108,7 @@
struct lm3692x_led {
struct mutex lock;
struct i2c_client *client;
- struct led_classdev led_dev;
+ struct led_init_data init_data;
struct regmap *regmap;
struct gpio_desc *enable_gpio;
struct regulator *regulator;
@@ -166,7 +166,8 @@ static int lm3692x_brightness_set(struct led_classdev *led_cdev,
enum led_brightness brt_val)
{
struct lm3692x_led *led =
- container_of(led_cdev, struct lm3692x_led, led_dev);
+ container_of(led_cdev->init_data, struct lm3692x_led,
+ init_data);
int ret;
int led_brightness_lsb = (brt_val >> 5);
@@ -319,49 +320,56 @@ static int lm3692x_init(struct lm3692x_led *led)
return ret;
}
-static int lm3692x_probe_dt(struct lm3692x_led *led)
+
+static int lm3692x_of_parse_cb(struct led_classdev *ld, struct fwnode_handle *fw,
+ struct led_properties *props)
{
- struct fwnode_handle *child = NULL;
- struct led_init_data init_data = {};
int ret;
+ struct lm3692x_led *led = container_of(ld->init_data,
+ struct lm3692x_led, init_data);
+
+ ret = fwnode_property_read_u32(fw, "reg", &led->led_enable);
+ if (ret)
+ dev_err(&led->client->dev, "reg DT property missing\n");
+
+ return ret;
+}
+
+static const struct led_ops lm3692x_ops = {
+ .brightness_set_blocking = lm3692x_brightness_set,
+};
+
+static int lm3692x_probe_dt(struct lm3692x_led *led)
+{
+ void *ret;
led->enable_gpio = devm_gpiod_get_optional(&led->client->dev,
"enable", GPIOD_OUT_LOW);
if (IS_ERR(led->enable_gpio)) {
- ret = PTR_ERR(led->enable_gpio);
- dev_err(&led->client->dev, "Failed to get enable gpio: %d\n",
- ret);
- return ret;
+ dev_err(&led->client->dev, "Failed to get enable gpio: %ld\n",
+ PTR_ERR(led->enable_gpio));
+ return PTR_ERR(led->enable_gpio);
}
led->regulator = devm_regulator_get(&led->client->dev, "vled");
if (IS_ERR(led->regulator))
led->regulator = NULL;
- child = device_get_next_child_node(&led->client->dev, child);
- if (!child) {
- dev_err(&led->client->dev, "No LED Child node\n");
- return -ENODEV;
- }
-
- fwnode_property_read_string(child, "linux,default-trigger",
- &led->led_dev.default_trigger);
-
- ret = fwnode_property_read_u32(child, "reg", &led->led_enable);
- if (ret) {
- dev_err(&led->client->dev, "reg DT property missing\n");
- return ret;
- }
-
- init_data.fwnode = child;
- init_data.devicename = led->client->name;
- init_data.default_label = ":";
-
- ret = devm_led_classdev_register_ext(&led->client->dev, &led->led_dev,
- &init_data);
- if (ret) {
- dev_err(&led->client->dev, "led register err: %d\n", ret);
- return ret;
+ /*
+ * RFC_NOTE: Do we have fixed node name here or do we need another way to
+ * do 'match'?
+ */
+ led->init_data.of_match = of_match_ptr("led_node_name_here");
+ led->init_data.of_parse_cb = lm3692x_of_parse_cb;
+ led->init_data.devicename = led->client->name;
+ led->init_data.default_label = ":";
+
+ ret = devm_led_classdev_register_dt(&led->client->dev, &lm3692x_ops,
+ &led->init_data);
+ if (IS_ERR(ret)) {
+ dev_err(&led->client->dev, "led register err: %ld\n",
+ PTR_ERR(ret));
+ return PTR_ERR(ret);
}
return 0;
@@ -379,7 +387,6 @@ static int lm3692x_probe(struct i2c_client *client,
mutex_init(&led->lock);
led->client = client;
- led->led_dev.brightness_set_blocking = lm3692x_brightness_set;
led->model_id = id->driver_data;
i2c_set_clientdata(client, led);
--
2.21.0
--
Matti Vaittinen, Linux device drivers
ROHM Semiconductors, Finland SWDC
Kiviharjunlenkki 1E
90220 OULU
FINLAND
~~~ "I don't think so," said Rene Descartes. Just then he vanished ~~~
Simon says - in Latin please.
~~~ "non cogito me" dixit Rene Descarte, deinde evanescavit ~~~
Thanks to Simon Glass for the translation =]
