[PATCH v6 5/5] leds: lm3533: Support initialization from Device Tree

From: Bjorn Andersson
Date: Tue Jan 31 2017 - 00:19:11 EST


From: Bjorn Andersson <bjorn.andersson@xxxxxxxxxxxxxx>

Implement support for initialization of the lm3533 LED driver from
Device Tree.

Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxxxxxx>
Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
---

Note that this patch can be merged independently of the other patches in the
series.

Changes since v5:
- None

Changes since v4:
- None

Changes since v3:
- Moved LED DT parsing from mfd driver
- Gave driver its own compatible

drivers/leds/leds-lm3533.c | 98 ++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 95 insertions(+), 3 deletions(-)

diff --git a/drivers/leds/leds-lm3533.c b/drivers/leds/leds-lm3533.c
index 5b529dc013d2..3eedad0ea9df 100644
--- a/drivers/leds/leds-lm3533.c
+++ b/drivers/leds/leds-lm3533.c
@@ -15,6 +15,7 @@
#include <linux/leds.h>
#include <linux/mfd/core.h>
#include <linux/mutex.h>
+#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/slab.h>

@@ -648,12 +649,92 @@ static int lm3533_led_setup(struct lm3533_led *led,
return lm3533_ctrlbank_set_pwm(&led->cb, pdata->pwm);
}

+static int lm3533_of_parse_pwm_zones(struct device_node *node)
+{
+ const char *propname = "ti,pwm-zones";
+ u32 zones[5];
+ int count;
+ int ret;
+ int i;
+
+ count = of_property_count_u32_elems(node, propname);
+ if (count == -EINVAL)
+ return 0;
+ if (count <= 0)
+ return count;
+ if (count >= ARRAY_SIZE(zones))
+ return -EINVAL;
+
+ ret = of_property_read_u32_array(node, propname, zones, count);
+ if (ret < 0)
+ return ret;
+
+ /* Enable pwm input, and enable the selected zones */
+ ret = BIT(0);
+ for (i = 0; i < count; i++)
+ ret |= BIT(zones[i] + 1);
+
+ return ret;
+}
+
+static struct lm3533_led_platform_data *lm3533_led_of_parse(struct device *dev,
+ int *id)
+{
+ struct lm3533_led_platform_data *led_pdata;
+ struct device_node *node = dev->of_node;
+ int ret;
+ u32 reg;
+ u32 val;
+
+ led_pdata = devm_kzalloc(dev, sizeof(*led_pdata), GFP_KERNEL);
+ if (!led_pdata)
+ return NULL;
+
+ ret = of_property_read_u32(node, "reg", &reg);
+ if (ret < 0) {
+ dev_err(dev, "invalid reg property\n");
+ return NULL;
+ }
+ *id = reg;
+
+ ret = of_property_read_string(node, "label",
+ (const char **)&led_pdata->name);
+ if (ret < 0) {
+ dev_err(dev, "unable to parse label\n");
+ return NULL;
+ }
+
+ ret = of_property_read_u32(node, "led-max-microamp", &val);
+ if (ret < 0) {
+ dev_err(dev, "unable to parse led-max-microamp\n");
+ return NULL;
+ }
+ led_pdata->max_current = val;
+
+ ret = of_property_read_string(node, "linux,default-trigger",
+ &led_pdata->default_trigger);
+ if (ret < 0 && ret != -EINVAL) {
+ dev_err(dev, "unable to parse default-trigger\n");
+ return NULL;
+ }
+
+ ret = lm3533_of_parse_pwm_zones(node);
+ if (ret < 0) {
+ dev_err(dev, "failed to parse ti,pwm-zones\n");
+ return NULL;
+ }
+ led_pdata->pwm = ret;
+
+ return led_pdata;
+}
+
static int lm3533_led_probe(struct platform_device *pdev)
{
struct lm3533 *lm3533;
struct lm3533_led_platform_data *pdata;
struct lm3533_led *led;
int ret;
+ int id;

dev_dbg(&pdev->dev, "%s\n", __func__);

@@ -661,14 +742,18 @@ static int lm3533_led_probe(struct platform_device *pdev)
if (!lm3533)
return -EINVAL;

+ id = pdev->id;
pdata = dev_get_platdata(&pdev->dev);
+ if (!pdata)
+ pdata = lm3533_led_of_parse(&pdev->dev, &id);
+
if (!pdata) {
dev_err(&pdev->dev, "no platform data\n");
return -EINVAL;
}

- if (pdev->id < 0 || pdev->id >= LM3533_LVCTRLBANK_COUNT) {
- dev_err(&pdev->dev, "illegal LED id %d\n", pdev->id);
+ if (id < 0 || id >= LM3533_LVCTRLBANK_COUNT) {
+ dev_err(&pdev->dev, "illegal LED id %d\n", id);
return -EINVAL;
}

@@ -684,7 +769,7 @@ static int lm3533_led_probe(struct platform_device *pdev)
led->cdev.blink_set = lm3533_led_blink_set;
led->cdev.brightness = LED_OFF;
led->cdev.groups = lm3533_led_attribute_groups,
- led->id = pdev->id;
+ led->id = id;

mutex_init(&led->mutex);

@@ -739,9 +824,16 @@ static void lm3533_led_shutdown(struct platform_device *pdev)
lm3533_led_set(&led->cdev, LED_OFF); /* disable blink */
}

+static const struct of_device_id lm3533_led_of_match[] = {
+ { .compatible = "ti,lm3533-led", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, lm3533_led_of_match);
+
static struct platform_driver lm3533_led_driver = {
.driver = {
.name = "lm3533-leds",
+ .of_match_table = lm3533_led_of_match,
},
.probe = lm3533_led_probe,
.remove = lm3533_led_remove,
--
2.11.0