leds: syscon: instantiate from platform device
Currently syscon LEDs will traverse the device tree looking for syscon devices
and if found, traverse any subnodes of these to identify matching children
and from there instantiate LED class devices.
This is not a good use of the Linux device model. Instead we have converted the
device trees to add the "simple-mfd" property to the MFD nexi spawning syscon
LEDs so that these will appear as platform devices in the system and we can
use the proper device probing mechanism.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/leds/leds-syscon.c b/drivers/leds/leds-syscon.c
index 6896e2d..d1660b0 100644
--- a/drivers/leds/leds-syscon.c
+++ b/drivers/leds/leds-syscon.c
@@ -20,6 +20,7 @@
* MA 02111-1307 USA
*/
#include <linux/io.h>
+#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
@@ -66,102 +67,101 @@
dev_err(sled->cdev.dev, "error updating LED status\n");
}
-static int __init syscon_leds_spawn(struct device_node *np,
- struct device *dev,
- struct regmap *map)
+static int syscon_led_probe(struct platform_device *pdev)
{
- struct device_node *child;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct device *parent;
+ struct regmap *map;
+ struct syscon_led *sled;
+ const char *state;
int ret;
- for_each_available_child_of_node(np, child) {
- struct syscon_led *sled;
- const char *state;
-
- /* Only check for register-bit-leds */
- if (of_property_match_string(child, "compatible",
- "register-bit-led") < 0)
- continue;
-
- sled = devm_kzalloc(dev, sizeof(*sled), GFP_KERNEL);
- if (!sled)
- return -ENOMEM;
-
- sled->map = map;
-
- if (of_property_read_u32(child, "offset", &sled->offset))
- return -EINVAL;
- if (of_property_read_u32(child, "mask", &sled->mask))
- return -EINVAL;
- sled->cdev.name =
- of_get_property(child, "label", NULL) ? : child->name;
- sled->cdev.default_trigger =
- of_get_property(child, "linux,default-trigger", NULL);
-
- state = of_get_property(child, "default-state", NULL);
- if (state) {
- if (!strcmp(state, "keep")) {
- u32 val;
-
- ret = regmap_read(map, sled->offset, &val);
- if (ret < 0)
- return ret;
- sled->state = !!(val & sled->mask);
- } else if (!strcmp(state, "on")) {
- sled->state = true;
- ret = regmap_update_bits(map, sled->offset,
- sled->mask,
- sled->mask);
- if (ret < 0)
- return ret;
- } else {
- sled->state = false;
- ret = regmap_update_bits(map, sled->offset,
- sled->mask, 0);
- if (ret < 0)
- return ret;
- }
- }
- sled->cdev.brightness_set = syscon_led_set;
-
- ret = led_classdev_register(dev, &sled->cdev);
- if (ret < 0)
- return ret;
-
- dev_info(dev, "registered LED %s\n", sled->cdev.name);
+ parent = dev->parent;
+ if (!parent) {
+ dev_err(dev, "no parent for syscon LED\n");
+ return -ENODEV;
}
+ map = syscon_node_to_regmap(parent->of_node);
+ if (!map) {
+ dev_err(dev, "no regmap for syscon LED parent\n");
+ return -ENODEV;
+ }
+
+ sled = devm_kzalloc(dev, sizeof(*sled), GFP_KERNEL);
+ if (!sled)
+ return -ENOMEM;
+
+ sled->map = map;
+
+ if (of_property_read_u32(np, "offset", &sled->offset))
+ return -EINVAL;
+ if (of_property_read_u32(np, "mask", &sled->mask))
+ return -EINVAL;
+ sled->cdev.name =
+ of_get_property(np, "label", NULL) ? : np->name;
+ sled->cdev.default_trigger =
+ of_get_property(np, "linux,default-trigger", NULL);
+
+ state = of_get_property(np, "default-state", NULL);
+ if (state) {
+ if (!strcmp(state, "keep")) {
+ u32 val;
+
+ ret = regmap_read(map, sled->offset, &val);
+ if (ret < 0)
+ return ret;
+ sled->state = !!(val & sled->mask);
+ } else if (!strcmp(state, "on")) {
+ sled->state = true;
+ ret = regmap_update_bits(map, sled->offset,
+ sled->mask,
+ sled->mask);
+ if (ret < 0)
+ return ret;
+ } else {
+ sled->state = false;
+ ret = regmap_update_bits(map, sled->offset,
+ sled->mask, 0);
+ if (ret < 0)
+ return ret;
+ }
+ }
+ sled->cdev.brightness_set = syscon_led_set;
+
+ ret = led_classdev_register(dev, &sled->cdev);
+ if (ret < 0)
+ return ret;
+
+ platform_set_drvdata(pdev, sled);
+ dev_info(dev, "registered LED %s\n", sled->cdev.name);
+
return 0;
}
-static int __init syscon_leds_init(void)
+static int syscon_led_remove(struct platform_device *pdev)
{
- struct device_node *np;
+ struct syscon_led *sled = platform_get_drvdata(pdev);
- for_each_of_allnodes(np) {
- struct platform_device *pdev;
- struct regmap *map;
- int ret;
-
- if (!of_device_is_compatible(np, "syscon"))
- continue;
-
- map = syscon_node_to_regmap(np);
- if (IS_ERR(map)) {
- pr_err("error getting regmap for syscon LEDs\n");
- continue;
- }
-
- /*
- * If the map is there, the device should be there, we allocate
- * memory on the syscon device's behalf here.
- */
- pdev = of_find_device_by_node(np);
- if (!pdev)
- return -ENODEV;
- ret = syscon_leds_spawn(np, &pdev->dev, map);
- if (ret)
- dev_err(&pdev->dev, "could not spawn syscon LEDs\n");
- }
-
+ led_classdev_unregister(&sled->cdev);
+ /* Turn it off */
+ regmap_update_bits(sled->map, sled->offset, sled->mask, 0);
return 0;
}
-device_initcall(syscon_leds_init);
+
+static const struct of_device_id of_syscon_leds_match[] = {
+ { .compatible = "register-bit-led", },
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, of_syscon_leds_match);
+
+static struct platform_driver syscon_led_driver = {
+ .probe = syscon_led_probe,
+ .remove = syscon_led_remove,
+ .driver = {
+ .name = "leds-syscon",
+ .of_match_table = of_syscon_leds_match,
+ },
+};
+module_platform_driver(syscon_led_driver);