diff options
Diffstat (limited to 'drivers/leds/leds-pca955x.c')
| -rw-r--r-- | drivers/leds/leds-pca955x.c | 137 |
1 files changed, 120 insertions, 17 deletions
diff --git a/drivers/leds/leds-pca955x.c b/drivers/leds/leds-pca955x.c index 5a5d376..f062d1e 100644 --- a/drivers/leds/leds-pca955x.c +++ b/drivers/leds/leds-pca955x.c @@ -53,6 +53,8 @@ #include <linux/slab.h> #include <linux/string.h> +#include <dt-bindings/leds/leds-pca955x.h> + /* LED select registers determine the source that drives LED outputs */ #define PCA955X_LS_LED_ON 0x0 /* Output LOW */ #define PCA955X_LS_LED_OFF 0x1 /* Output HI-Z */ @@ -118,6 +120,9 @@ struct pca955x { struct pca955x_led *leds; struct pca955x_chipdef *chipdef; struct i2c_client *client; +#ifdef CONFIG_LEDS_PCA955X_GPIO + struct gpio_chip gpio; +#endif }; struct pca955x_led { @@ -125,6 +130,7 @@ struct pca955x_led { struct led_classdev led_cdev; int led_num; /* 0 .. 15 potentially */ char name[32]; + u32 type; const char *default_trigger; }; @@ -259,6 +265,65 @@ static int pca955x_led_set(struct led_classdev *led_cdev, return 0; } +#ifdef CONFIG_LEDS_PCA955X_GPIO +/* + * Read the INPUT register, which contains the state of LEDs. + */ +static u8 pca955x_read_input(struct i2c_client *client, int n) +{ + return (u8)i2c_smbus_read_byte_data(client, n); +} + +static int pca955x_gpio_request_pin(struct gpio_chip *gc, unsigned int offset) +{ + struct pca955x *pca955x = gpiochip_get_data(gc); + struct pca955x_led *led = &pca955x->leds[offset]; + + if (led->type == PCA955X_TYPE_GPIO) + return 0; + + return -EBUSY; +} + +static void pca955x_gpio_set_value(struct gpio_chip *gc, unsigned int offset, + int val) +{ + struct pca955x *pca955x = gpiochip_get_data(gc); + struct pca955x_led *led = &pca955x->leds[offset]; + + if (val) + pca955x_led_set(&led->led_cdev, LED_FULL); + else + pca955x_led_set(&led->led_cdev, LED_OFF); +} + +static int pca955x_gpio_get_value(struct gpio_chip *gc, unsigned int offset) +{ + struct pca955x *pca955x = gpiochip_get_data(gc); + struct pca955x_led *led = &pca955x->leds[offset]; + u8 reg = pca955x_read_input(pca955x->client, led->led_num / 8); + + return !!(reg & (1 << (led->led_num % 8))); +} + +static int pca955x_gpio_direction_input(struct gpio_chip *gc, + unsigned int offset) +{ + /* To use as input ensure pin is not driven */ + pca955x_gpio_set_value(gc, offset, 0); + + return 0; +} + +static int pca955x_gpio_direction_output(struct gpio_chip *gc, + unsigned int offset, int val) +{ + pca955x_gpio_set_value(gc, offset, val); + + return 0; +} +#endif /* CONFIG_LEDS_PCA955X_GPIO */ + #if IS_ENABLED(CONFIG_OF) static struct pca955x_platform_data * pca955x_pdata_of_init(struct i2c_client *client, struct pca955x_chipdef *chip) @@ -297,6 +362,8 @@ pca955x_pdata_of_init(struct i2c_client *client, struct pca955x_chipdef *chip) snprintf(pdata->leds[reg].name, sizeof(pdata->leds[reg].name), "%s", name); + pdata->leds[reg].type = PCA955X_TYPE_LED; + of_property_read_u32(child, "type", &pdata->leds[reg].type); of_property_read_string(child, "linux,default-trigger", &pdata->leds[reg].default_trigger); } @@ -332,6 +399,7 @@ static int pca955x_probe(struct i2c_client *client, struct i2c_adapter *adapter; int i, err; struct pca955x_platform_data *pdata; + int ngpios = 0; if (id) { chip = &pca955x_chipdefs[id->driver_data]; @@ -392,9 +460,19 @@ static int pca955x_probe(struct i2c_client *client, pca955x_led = &pca955x->leds[i]; pca955x_led->led_num = i; pca955x_led->pca955x = pca955x; - - /* Platform data can specify LED names and default triggers */ - if (pdata) { + pca955x_led->type = pdata->leds[i].type; + + switch (pca955x_led->type) { + case PCA955X_TYPE_NONE: + break; + case PCA955X_TYPE_GPIO: + ngpios++; + break; + case PCA955X_TYPE_LED: + /* + * Platform data can specify LED names and + * default triggers + */ if (pdata->leds[i].name) snprintf(pca955x_led->name, sizeof(pca955x_led->name), "pca955x:%s", @@ -402,23 +480,20 @@ static int pca955x_probe(struct i2c_client *client, if (pdata->leds[i].default_trigger) pca955x_led->led_cdev.default_trigger = pdata->leds[i].default_trigger; - } else { - snprintf(pca955x_led->name, sizeof(pca955x_led->name), - "pca955x:%d", i); - } - pca955x_led->led_cdev.name = pca955x_led->name; - pca955x_led->led_cdev.brightness_set_blocking = pca955x_led_set; + pca955x_led->led_cdev.name = pca955x_led->name; + pca955x_led->led_cdev.brightness_set_blocking = + pca955x_led_set; - err = devm_led_classdev_register(&client->dev, - &pca955x_led->led_cdev); - if (err) - return err; - } + err = devm_led_classdev_register(&client->dev, + &pca955x_led->led_cdev); + if (err) + return err; - /* Turn off LEDs */ - for (i = 0; i < pca95xx_num_led_regs(chip->bits); i++) - pca955x_write_ls(client, i, 0x55); + /* Turn off LED */ + pca955x_led_set(&pca955x_led->led_cdev, LED_OFF); + } + } /* PWM0 is used for half brightness or 50% duty cycle */ pca955x_write_pwm(client, 0, 255-LED_HALF); @@ -430,6 +505,34 @@ static int pca955x_probe(struct i2c_client *client, pca955x_write_psc(client, 0, 0); pca955x_write_psc(client, 1, 0); +#ifdef CONFIG_LEDS_PCA955X_GPIO + if (ngpios) { + pca955x->gpio.label = "gpio-pca955x"; + pca955x->gpio.direction_input = pca955x_gpio_direction_input; + pca955x->gpio.direction_output = pca955x_gpio_direction_output; + pca955x->gpio.set = pca955x_gpio_set_value; + pca955x->gpio.get = pca955x_gpio_get_value; + pca955x->gpio.request = pca955x_gpio_request_pin; + pca955x->gpio.can_sleep = 1; + pca955x->gpio.base = -1; + pca955x->gpio.ngpio = ngpios; + pca955x->gpio.parent = &client->dev; + pca955x->gpio.owner = THIS_MODULE; + + err = devm_gpiochip_add_data(&client->dev, &pca955x->gpio, + pca955x); + if (err) { + /* Use data->gpio.dev as a flag for freeing gpiochip */ + pca955x->gpio.parent = NULL; + dev_warn(&client->dev, "could not add gpiochip\n"); + return err; + } + dev_info(&client->dev, "gpios %i...%i\n", + pca955x->gpio.base, pca955x->gpio.base + + pca955x->gpio.ngpio - 1); + } +#endif + return 0; } |
