diff options
| -rw-r--r-- | Documentation/devicetree/bindings/leds/pca963x.txt | 3 | ||||
| -rw-r--r-- | drivers/leds/leds-pca963x.c | 18 |
2 files changed, 18 insertions, 3 deletions
diff --git a/Documentation/devicetree/bindings/leds/pca963x.txt b/Documentation/devicetree/bindings/leds/pca963x.txt index dafbe9931c2b..dfbdb123a9bf 100644 --- a/Documentation/devicetree/bindings/leds/pca963x.txt +++ b/Documentation/devicetree/bindings/leds/pca963x.txt @@ -7,6 +7,9 @@ Optional properties: - nxp,totem-pole : use totem pole (push-pull) instead of open-drain (pca9632 defaults to open-drain, newer chips to totem pole) - nxp,hw-blink : use hardware blinking instead of software blinking +- nxp,period-scale : In some configurations, the chip blinks faster than expected. + This parameter provides a scaling ratio (fixed point, decimal divided + by 1000) to compensate, e.g. 1300=1.3x and 750=0.75x. Each led is represented as a sub-node of the nxp,pca963x device. diff --git a/drivers/leds/leds-pca963x.c b/drivers/leds/leds-pca963x.c index 407eba11e187..b6ce1f2ec33e 100644 --- a/drivers/leds/leds-pca963x.c +++ b/drivers/leds/leds-pca963x.c @@ -59,6 +59,7 @@ struct pca963x_chipdef { u8 grpfreq; u8 ledout_base; int n_leds; + unsigned int scaling; }; static struct pca963x_chipdef pca963x_chipdefs[] = { @@ -189,6 +190,14 @@ static int pca963x_led_set(struct led_classdev *led_cdev, return pca963x_brightness(pca963x, value); } +static unsigned int pca963x_period_scale(struct pca963x_led *pca963x, + unsigned int val) +{ + unsigned int scaling = pca963x->chip->chipdef->scaling; + + return scaling ? DIV_ROUND_CLOSEST(val * scaling, 1000) : val; +} + static int pca963x_blink_set(struct led_classdev *led_cdev, unsigned long *delay_on, unsigned long *delay_off) { @@ -207,14 +216,14 @@ static int pca963x_blink_set(struct led_classdev *led_cdev, time_off = 500; } - period = time_on + time_off; + period = pca963x_period_scale(pca963x, time_on + time_off); /* If period not supported by hardware, default to someting sane. */ if ((period < PCA963X_BLINK_PERIOD_MIN) || (period > PCA963X_BLINK_PERIOD_MAX)) { time_on = 500; time_off = 500; - period = time_on + time_off; + period = pca963x_period_scale(pca963x, 1000); } /* @@ -222,7 +231,7 @@ static int pca963x_blink_set(struct led_classdev *led_cdev, * (time_on / period) = (GDC / 256) -> * GDC = ((time_on * 256) / period) */ - gdc = (time_on * 256) / period; + gdc = (pca963x_period_scale(pca963x, time_on) * 256) / period; /* * From manual: period = ((GFRQ + 1) / 24) in seconds. @@ -294,6 +303,9 @@ pca963x_dt_init(struct i2c_client *client, struct pca963x_chipdef *chip) else pdata->blink_type = PCA963X_SW_BLINK; + if (of_property_read_u32(np, "nxp,period-scale", &chip->scaling)) + chip->scaling = 1000; + return pdata; } |