backlight: lp855x: add a device tree structure
Enable supporting the DT structure of LP855x family devices. If the
platform data is NULL, the driver tries to parse a DT structure. Then,
the platform data is copied from the DT. Documentation is added as well.
Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/video/backlight/lp855x_bl.c b/drivers/video/backlight/lp855x_bl.c
index f558f8f..a0e1e02 100644
--- a/drivers/video/backlight/lp855x_bl.c
+++ b/drivers/video/backlight/lp855x_bl.c
@@ -14,6 +14,7 @@
#include <linux/i2c.h>
#include <linux/backlight.h>
#include <linux/err.h>
+#include <linux/of.h>
#include <linux/platform_data/lp855x.h>
#include <linux/pwm.h>
@@ -338,15 +339,71 @@
.attrs = lp855x_attributes,
};
+#ifdef CONFIG_OF
+static int lp855x_parse_dt(struct device *dev, struct device_node *node)
+{
+ struct lp855x_platform_data *pdata;
+ int rom_length;
+
+ if (!node) {
+ dev_err(dev, "no platform data\n");
+ return -EINVAL;
+ }
+
+ pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return -ENOMEM;
+
+ 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);
+ of_property_read_u32(node, "pwm-period", &pdata->period_ns);
+
+ /* Fill ROM platform data if defined */
+ rom_length = of_get_child_count(node);
+ if (rom_length > 0) {
+ struct lp855x_rom_data *rom;
+ struct device_node *child;
+ int i = 0;
+
+ rom = devm_kzalloc(dev, sizeof(*rom) * rom_length, GFP_KERNEL);
+ if (!rom)
+ return -ENOMEM;
+
+ for_each_child_of_node(node, child) {
+ of_property_read_u8(child, "rom-addr", &rom[i].addr);
+ of_property_read_u8(child, "rom-val", &rom[i].val);
+ i++;
+ }
+
+ pdata->size_program = rom_length;
+ pdata->rom_data = &rom[0];
+ }
+
+ dev->platform_data = pdata;
+
+ return 0;
+}
+#else
+static int lp855x_parse_dt(struct device *dev, struct device_node *node)
+{
+ return -EINVAL;
+}
+#endif
+
static int lp855x_probe(struct i2c_client *cl, const struct i2c_device_id *id)
{
struct lp855x *lp;
struct lp855x_platform_data *pdata = cl->dev.platform_data;
+ struct device_node *node = cl->dev.of_node;
int ret;
if (!pdata) {
- dev_err(&cl->dev, "no platform data supplied\n");
- return -EINVAL;
+ ret = lp855x_parse_dt(&cl->dev, node);
+ if (ret < 0)
+ return ret;
+
+ pdata = cl->dev.platform_data;
}
if (!i2c_check_functionality(cl->adapter, I2C_FUNC_SMBUS_I2C_BLOCK))
@@ -408,6 +465,17 @@
return 0;
}
+static const struct of_device_id lp855x_dt_ids[] = {
+ { .compatible = "ti,lp8550", },
+ { .compatible = "ti,lp8551", },
+ { .compatible = "ti,lp8552", },
+ { .compatible = "ti,lp8553", },
+ { .compatible = "ti,lp8556", },
+ { .compatible = "ti,lp8557", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, lp855x_dt_ids);
+
static const struct i2c_device_id lp855x_ids[] = {
{"lp8550", LP8550},
{"lp8551", LP8551},
@@ -422,6 +490,7 @@
static struct i2c_driver lp855x_driver = {
.driver = {
.name = "lp855x",
+ .of_match_table = of_match_ptr(lp855x_dt_ids),
},
.probe = lp855x_probe,
.remove = lp855x_remove,