diff options
| author | Matt Ranostay <mranostay@gmail.com> | 2016-10-28 18:20:42 -0700 |
|---|---|---|
| committer | Jacek Anaszewski <j.anaszewski@samsung.com> | 2016-11-22 12:07:04 +0100 |
| commit | a8c170b015ff6695641bdfbdb74729411ba1e9e5 (patch) | |
| tree | 05c4f0b053eae8a9613d829673b400882f307a24 | |
| parent | 90a5537bd83b461180120c926b7795c7dd44093a (diff) | |
leds: pca963x: enable low-power state
Allow chip to enter low power state when no LEDs are being lit or in
blink mode.
Cc: Peter Meerwald <p.meerwald@bct-electronic.com>,
Cc: Ricardo Ribalda <ricardo.ribalda@gmail.com>
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Matt Ranostay <matt@ranostay.consulting>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
| -rw-r--r-- | drivers/leds/leds-pca963x.c | 40 |
1 files changed, 33 insertions, 7 deletions
diff --git a/drivers/leds/leds-pca963x.c b/drivers/leds/leds-pca963x.c index b6ce1f2ec33e..46fbf935944a 100644 --- a/drivers/leds/leds-pca963x.c +++ b/drivers/leds/leds-pca963x.c @@ -103,6 +103,7 @@ struct pca963x { struct mutex mutex; struct i2c_client *client; struct pca963x_led *leds; + unsigned long leds_on; }; struct pca963x_led { @@ -124,7 +125,6 @@ static int pca963x_brightness(struct pca963x_led *pca963x, u8 mask = 0x3 << shift; int ret; - mutex_lock(&pca963x->chip->mutex); ledout = i2c_smbus_read_byte_data(pca963x->chip->client, ledout_addr); switch (brightness) { case LED_FULL: @@ -141,14 +141,13 @@ static int pca963x_brightness(struct pca963x_led *pca963x, PCA963X_PWM_BASE + pca963x->led_num, brightness); if (ret < 0) - goto unlock; + return ret; ret = i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr, (ledout & ~mask) | (PCA963X_LED_PWM << shift)); break; } -unlock: - mutex_unlock(&pca963x->chip->mutex); + return ret; } @@ -180,14 +179,41 @@ static void pca963x_blink(struct pca963x_led *pca963x) mutex_unlock(&pca963x->chip->mutex); } +static int pca963x_power_state(struct pca963x_led *pca963x) +{ + unsigned long *leds_on = &pca963x->chip->leds_on; + unsigned long cached_leds = pca963x->chip->leds_on; + + if (pca963x->led_cdev.brightness) + set_bit(pca963x->led_num, leds_on); + else + clear_bit(pca963x->led_num, leds_on); + + if (!(*leds_on) != !cached_leds) + return i2c_smbus_write_byte_data(pca963x->chip->client, + PCA963X_MODE1, *leds_on ? 0 : BIT(4)); + + return 0; +} + static int pca963x_led_set(struct led_classdev *led_cdev, enum led_brightness value) { struct pca963x_led *pca963x; + int ret; pca963x = container_of(led_cdev, struct pca963x_led, led_cdev); - return pca963x_brightness(pca963x, value); + mutex_lock(&pca963x->chip->mutex); + + ret = pca963x_brightness(pca963x, value); + if (ret < 0) + goto unlock; + ret = pca963x_power_state(pca963x); + +unlock: + mutex_unlock(&pca963x->chip->mutex); + return ret; } static unsigned int pca963x_period_scale(struct pca963x_led *pca963x, @@ -403,8 +429,8 @@ static int pca963x_probe(struct i2c_client *client, goto exit; } - /* Disable LED all-call address and set normal mode */ - i2c_smbus_write_byte_data(client, PCA963X_MODE1, 0x00); + /* Disable LED all-call address, and power down initially */ + i2c_smbus_write_byte_data(client, PCA963X_MODE1, BIT(4)); if (pdata) { /* Configure output: open-drain or totem pole (push-pull) */ |