leds: pca955x: add device tree support
authorCédric Le Goater <clg@kaod.org>
Tue, 8 Aug 2017 13:42:37 +0000 (15:42 +0200)
committerJacek Anaszewski <jacek.anaszewski@gmail.com>
Mon, 14 Aug 2017 20:21:14 +0000 (22:21 +0200)
It will be used in a following patch to define different operation
modes for each pin.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
drivers/leds/leds-pca955x.c

index 9a873118ea5fcf4ff7adae18e03b3a351936df16..2d34009d00e6de766fdc3b34868569ccdd3ebaa4 100644 (file)
  */
 
 #include <linux/acpi.h>
-#include <linux/module.h>
-#include <linux/delay.h>
-#include <linux/string.h>
 #include <linux/ctype.h>
-#include <linux/leds.h>
+#include <linux/delay.h>
 #include <linux/err.h>
+#include <linux/gpio.h>
 #include <linux/i2c.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/of.h>
 #include <linux/slab.h>
+#include <linux/string.h>
 
 /* LED select registers determine the source that drives LED outputs */
 #define PCA955X_LS_LED_ON      0x0     /* Output LOW */
@@ -122,6 +125,12 @@ struct pca955x_led {
        struct led_classdev     led_cdev;
        int                     led_num;        /* 0 .. 15 potentially */
        char                    name[32];
+       const char              *default_trigger;
+};
+
+struct pca955x_platform_data {
+       struct pca955x_led      *leds;
+       int                     num_leds;
 };
 
 /* 8 bits per input register */
@@ -250,6 +259,70 @@ static int pca955x_led_set(struct led_classdev *led_cdev,
        return 0;
 }
 
+#if IS_ENABLED(CONFIG_OF)
+static struct pca955x_platform_data *
+pca955x_pdata_of_init(struct i2c_client *client, struct pca955x_chipdef *chip)
+{
+       struct device_node *np = client->dev.of_node;
+       struct device_node *child;
+       struct pca955x_platform_data *pdata;
+       int count;
+
+       count = of_get_child_count(np);
+       if (!count || count > chip->bits)
+               return ERR_PTR(-ENODEV);
+
+       pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
+       if (!pdata)
+               return ERR_PTR(-ENOMEM);
+
+       pdata->leds = devm_kzalloc(&client->dev,
+                                  sizeof(struct pca955x_led) * chip->bits,
+                                  GFP_KERNEL);
+       if (!pdata->leds)
+               return ERR_PTR(-ENOMEM);
+
+       for_each_child_of_node(np, child) {
+               const char *name;
+               u32 reg;
+               int res;
+
+               res = of_property_read_u32(child, "reg", &reg);
+               if ((res != 0) || (reg >= chip->bits))
+                       continue;
+
+               if (of_property_read_string(child, "label", &name))
+                       name = child->name;
+
+               snprintf(pdata->leds[reg].name, sizeof(pdata->leds[reg].name),
+                        "%s", name);
+
+               of_property_read_string(child, "linux,default-trigger",
+                                       &pdata->leds[reg].default_trigger);
+       }
+
+       pdata->num_leds = chip->bits;
+
+       return pdata;
+}
+
+static const struct of_device_id of_pca955x_match[] = {
+       { .compatible = "nxp,pca9550", .data = (void *)pca9550 },
+       { .compatible = "nxp,pca9551", .data = (void *)pca9551 },
+       { .compatible = "nxp,pca9552", .data = (void *)pca9552 },
+       { .compatible = "nxp,pca9553", .data = (void *)pca9553 },
+       {},
+};
+
+MODULE_DEVICE_TABLE(of, of_pca955x_match);
+#else
+static struct pca955x_platform_data *
+pca955x_pdata_of_init(struct i2c_client *client, struct pca955x_chipdef *chip)
+{
+       return ERR_PTR(-ENODEV);
+}
+#endif
+
 static int pca955x_probe(struct i2c_client *client,
                                        const struct i2c_device_id *id)
 {
@@ -257,8 +330,8 @@ static int pca955x_probe(struct i2c_client *client,
        struct pca955x_led *pca955x_led;
        struct pca955x_chipdef *chip;
        struct i2c_adapter *adapter;
-       struct led_platform_data *pdata;
        int i, err;
+       struct pca955x_platform_data *pdata;
 
        if (id) {
                chip = &pca955x_chipdefs[id->driver_data];
@@ -272,6 +345,11 @@ static int pca955x_probe(struct i2c_client *client,
        }
        adapter = to_i2c_adapter(client->dev.parent);
        pdata = dev_get_platdata(&client->dev);
+       if (!pdata) {
+               pdata = pca955x_pdata_of_init(client, chip);
+               if (IS_ERR(pdata))
+                       return PTR_ERR(pdata);
+       }
 
        /* Make sure the slave address / chip type combo given is possible */
        if ((client->addr & ~((1 << chip->slv_addr_shift) - 1)) !=
@@ -288,13 +366,11 @@ static int pca955x_probe(struct i2c_client *client,
        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
                return -EIO;
 
-       if (pdata) {
-               if (pdata->num_leds != chip->bits) {
-                       dev_err(&client->dev, "board info claims %d LEDs"
-                                       " on a %d-bit chip\n",
-                                       pdata->num_leds, chip->bits);
-                       return -ENODEV;
-               }
+       if (pdata->num_leds != chip->bits) {
+               dev_err(&client->dev,
+                       "board info claims %d LEDs on a %d-bit chip\n",
+                       pdata->num_leds, chip->bits);
+               return -ENODEV;
        }
 
        pca955x = devm_kzalloc(&client->dev, sizeof(*pca955x), GFP_KERNEL);
@@ -378,6 +454,7 @@ static struct i2c_driver pca955x_driver = {
        .driver = {
                .name   = "leds-pca955x",
                .acpi_match_table = ACPI_PTR(pca955x_acpi_ids),
+               .of_match_table = of_match_ptr(of_pca955x_match),
        },
        .probe  = pca955x_probe,
        .remove = pca955x_remove,