diff options
| -rw-r--r-- | drivers/leds/leds-pca955x.c | 114 |
1 files changed, 83 insertions, 31 deletions
diff --git a/drivers/leds/leds-pca955x.c b/drivers/leds/leds-pca955x.c index 09303fd1fdc6..905729191d3e 100644 --- a/drivers/leds/leds-pca955x.c +++ b/drivers/leds/leds-pca955x.c @@ -165,13 +165,18 @@ static inline u8 pca955x_ledsel(u8 oldval, int led_num, int state) * Write to frequency prescaler register, used to program the * period of the PWM output. period = (PSCx + 1) / 38 */ -static void pca955x_write_psc(struct i2c_client *client, int n, u8 val) +static int pca955x_write_psc(struct i2c_client *client, int n, u8 val) { struct pca955x *pca955x = i2c_get_clientdata(client); + int ret; - i2c_smbus_write_byte_data(client, + ret = i2c_smbus_write_byte_data(client, pca95xx_num_input_regs(pca955x->chipdef->bits) + 2*n, val); + if (ret < 0) + dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n", + __func__, n, val, ret); + return ret; } /* @@ -181,38 +186,56 @@ static void pca955x_write_psc(struct i2c_client *client, int n, u8 val) * * Duty cycle is (256 - PWMx) / 256 */ -static void pca955x_write_pwm(struct i2c_client *client, int n, u8 val) +static int pca955x_write_pwm(struct i2c_client *client, int n, u8 val) { struct pca955x *pca955x = i2c_get_clientdata(client); + int ret; - i2c_smbus_write_byte_data(client, + ret = i2c_smbus_write_byte_data(client, pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + 2*n, val); + if (ret < 0) + dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n", + __func__, n, val, ret); + return ret; } /* * Write to LED selector register, which determines the source that * drives the LED output. */ -static void pca955x_write_ls(struct i2c_client *client, int n, u8 val) +static int pca955x_write_ls(struct i2c_client *client, int n, u8 val) { struct pca955x *pca955x = i2c_get_clientdata(client); + int ret; - i2c_smbus_write_byte_data(client, + ret = i2c_smbus_write_byte_data(client, pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n, val); + if (ret < 0) + dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n", + __func__, n, val, ret); + return ret; } /* * Read the LED selector register, which determines the source that * drives the LED output. */ -static u8 pca955x_read_ls(struct i2c_client *client, int n) +static int pca955x_read_ls(struct i2c_client *client, int n, u8 *val) { struct pca955x *pca955x = i2c_get_clientdata(client); + int ret; - return (u8) i2c_smbus_read_byte_data(client, + ret = i2c_smbus_read_byte_data(client, pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n); + if (ret < 0) { + dev_err(&client->dev, "%s: reg 0x%x, err %d\n", + __func__, n, ret); + return ret; + } + *val = (u8)ret; + return 0; } static int pca955x_led_set(struct led_classdev *led_cdev, @@ -223,6 +246,7 @@ static int pca955x_led_set(struct led_classdev *led_cdev, u8 ls; int chip_ls; /* which LSx to use (0-3 potentially) */ int ls_led; /* which set of bits within LSx to use (0-3) */ + int ret; pca955x_led = container_of(led_cdev, struct pca955x_led, led_cdev); pca955x = pca955x_led->pca955x; @@ -232,7 +256,9 @@ static int pca955x_led_set(struct led_classdev *led_cdev, mutex_lock(&pca955x->lock); - ls = pca955x_read_ls(pca955x->client, chip_ls); + ret = pca955x_read_ls(pca955x->client, chip_ls, &ls); + if (ret) + goto out; switch (value) { case LED_FULL: @@ -252,26 +278,37 @@ static int pca955x_led_set(struct led_classdev *led_cdev, * OFF, HALF, or FULL. But, this is probably better than * just turning off for all other values. */ - pca955x_write_pwm(pca955x->client, 1, - 255 - value); + ret = pca955x_write_pwm(pca955x->client, 1, 255 - value); + if (ret) + goto out; ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK1); break; } - pca955x_write_ls(pca955x->client, chip_ls, ls); + ret = pca955x_write_ls(pca955x->client, chip_ls, ls); +out: mutex_unlock(&pca955x->lock); - return 0; + return ret; } #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) +static int pca955x_read_input(struct i2c_client *client, int n, u8 *val) { - return (u8)i2c_smbus_read_byte_data(client, n); + int ret = i2c_smbus_read_byte_data(client, n); + + if (ret < 0) { + dev_err(&client->dev, "%s: reg 0x%x, err %d\n", + __func__, n, ret); + return ret; + } + *val = (u8)ret; + return 0; + } static int pca955x_gpio_request_pin(struct gpio_chip *gc, unsigned int offset) @@ -285,23 +322,32 @@ static int pca955x_gpio_request_pin(struct gpio_chip *gc, unsigned int offset) return -EBUSY; } -static void pca955x_gpio_set_value(struct gpio_chip *gc, unsigned int offset, - int val) +static int pca955x_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); + return pca955x_led_set(&led->led_cdev, LED_FULL); else - pca955x_led_set(&led->led_cdev, LED_OFF); + return pca955x_led_set(&led->led_cdev, LED_OFF); +} + +static void pca955x_gpio_set_value(struct gpio_chip *gc, unsigned int offset, + int val) +{ + pca955x_set_value(gc, offset, val); } 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); + u8 reg = 0; + + /* There is nothing we can do about errors */ + pca955x_read_input(pca955x->client, led->led_num / 8, ®); return !!(reg & (1 << (led->led_num % 8))); } @@ -310,17 +356,13 @@ 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; + return pca955x_set_value(gc, offset, 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; + return pca955x_set_value(gc, offset, val); } #endif /* CONFIG_LEDS_PCA955X_GPIO */ @@ -495,19 +537,29 @@ static int pca955x_probe(struct i2c_client *client, return err; /* Turn off LED */ - pca955x_led_set(&pca955x_led->led_cdev, LED_OFF); + err = pca955x_led_set(&pca955x_led->led_cdev, LED_OFF); + if (err) + return err; } } /* PWM0 is used for half brightness or 50% duty cycle */ - pca955x_write_pwm(client, 0, 255-LED_HALF); + err = pca955x_write_pwm(client, 0, 255 - LED_HALF); + if (err) + return err; /* PWM1 is used for variable brightness, default to OFF */ - pca955x_write_pwm(client, 1, 0); + err = pca955x_write_pwm(client, 1, 0); + if (err) + return err; /* Set to fast frequency so we do not see flashing */ - pca955x_write_psc(client, 0, 0); - pca955x_write_psc(client, 1, 0); + err = pca955x_write_psc(client, 0, 0); + if (err) + return err; + err = pca955x_write_psc(client, 1, 0); + if (err) + return err; #ifdef CONFIG_LEDS_PCA955X_GPIO if (ngpios) { |