leds-lp55xx: support device specific attributes

 To support device specific attributes, new common driver function is added.
 Eventually those are created on registering the sysfs with common dev attrs.
 Furthermore, this patch makes adding device attributes simple in each driver.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>

2 files changed, 16 insertions, 1 deletions

diff --git a/drivers/leds/leds-lp55xx-common.c b/drivers/leds/leds-lp55xx-common.c
index 578902ab604f..9638ad4dc635 100644
--- a/drivers/leds/leds-lp55xx-common.c
+++ b/drivers/leds/leds-lp55xx-common.c
@@ -493,8 +493,19 @@ EXPORT_SYMBOL_GPL(lp55xx_unregister_leds);
 int lp55xx_register_sysfs(struct lp55xx_chip *chip)
 {
         struct device *dev = &chip->cl->dev;
+        struct lp55xx_device_config *cfg = chip->cfg;
+        int ret;
+
+        if (!cfg->run_engine || !cfg->firmware_cb)
+                goto dev_specific_attrs;
+
+        ret = sysfs_create_group(&dev->kobj, &lp55xx_engine_attr_group);
+        if (ret)
+                return ret;
 
-        return sysfs_create_group(&dev->kobj, &lp55xx_engine_attr_group);
+dev_specific_attrs:
+        return cfg->dev_attr_group ?
+                sysfs_create_group(&dev->kobj, cfg->dev_attr_group) : 0;
 }
 EXPORT_SYMBOL_GPL(lp55xx_register_sysfs);
 
diff --git a/drivers/leds/leds-lp55xx-common.h b/drivers/leds/leds-lp55xx-common.h
index 8473abf9830c..64eb78da1c4b 100644
--- a/drivers/leds/leds-lp55xx-common.h
+++ b/drivers/leds/leds-lp55xx-common.h
@@ -45,6 +45,7 @@ struct lp55xx_reg {
  * @set_led_current    : LED current set function
  * @firmware_cb        : Call function when the firmware is loaded
  * @run_engine         : Run internal engine for pattern
+ * @dev_attr_group     : Device specific attributes
  */
 struct lp55xx_device_config {
         const struct lp55xx_reg reset;
@@ -65,6 +66,9 @@ struct lp55xx_device_config {
 
         /* used for running firmware LED patterns */
         void (*run_engine) (struct lp55xx_chip *chip, bool start);
+
+        /* additional device specific attributes */
+        const struct attribute_group *dev_attr_group;
 };
 
 /*