diff options
author | Matt Ranostay <mranostay@gmail.com> | 2016-10-13 09:16:12 -0400 |
---|---|---|
committer | Jacek Anaszewski <j.anaszewski@samsung.com> | 2016-11-22 06:07:04 -0500 |
commit | 35c7d30179fbc17af7281ccea18e6d74c003e448 (patch) | |
tree | d49f1992a6f3578f64d7750396d86a2f20db6a96 /drivers/leds | |
parent | ed25e9cae1ab8e84556c9413fd5de0a9da8f3657 (diff) |
leds: pca963x: workaround group blink scaling issue
PCA9632TK part seems to incorrectly blink at ~1.3x of the programmed
rate. This patchset add a nxp,period-scale devicetree property to
adjust for this misconfiguration.
Signed-off-by: Matt Ranostay <matt@ranostay.consulting>
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Diffstat (limited to 'drivers/leds')
-rw-r--r-- | drivers/leds/leds-pca963x.c | 18 |
1 files changed, 15 insertions, 3 deletions
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 { | |||
59 | u8 grpfreq; | 59 | u8 grpfreq; |
60 | u8 ledout_base; | 60 | u8 ledout_base; |
61 | int n_leds; | 61 | int n_leds; |
62 | unsigned int scaling; | ||
62 | }; | 63 | }; |
63 | 64 | ||
64 | static struct pca963x_chipdef pca963x_chipdefs[] = { | 65 | static struct pca963x_chipdef pca963x_chipdefs[] = { |
@@ -189,6 +190,14 @@ static int pca963x_led_set(struct led_classdev *led_cdev, | |||
189 | return pca963x_brightness(pca963x, value); | 190 | return pca963x_brightness(pca963x, value); |
190 | } | 191 | } |
191 | 192 | ||
193 | static unsigned int pca963x_period_scale(struct pca963x_led *pca963x, | ||
194 | unsigned int val) | ||
195 | { | ||
196 | unsigned int scaling = pca963x->chip->chipdef->scaling; | ||
197 | |||
198 | return scaling ? DIV_ROUND_CLOSEST(val * scaling, 1000) : val; | ||
199 | } | ||
200 | |||
192 | static int pca963x_blink_set(struct led_classdev *led_cdev, | 201 | static int pca963x_blink_set(struct led_classdev *led_cdev, |
193 | unsigned long *delay_on, unsigned long *delay_off) | 202 | unsigned long *delay_on, unsigned long *delay_off) |
194 | { | 203 | { |
@@ -207,14 +216,14 @@ static int pca963x_blink_set(struct led_classdev *led_cdev, | |||
207 | time_off = 500; | 216 | time_off = 500; |
208 | } | 217 | } |
209 | 218 | ||
210 | period = time_on + time_off; | 219 | period = pca963x_period_scale(pca963x, time_on + time_off); |
211 | 220 | ||
212 | /* If period not supported by hardware, default to someting sane. */ | 221 | /* If period not supported by hardware, default to someting sane. */ |
213 | if ((period < PCA963X_BLINK_PERIOD_MIN) || | 222 | if ((period < PCA963X_BLINK_PERIOD_MIN) || |
214 | (period > PCA963X_BLINK_PERIOD_MAX)) { | 223 | (period > PCA963X_BLINK_PERIOD_MAX)) { |
215 | time_on = 500; | 224 | time_on = 500; |
216 | time_off = 500; | 225 | time_off = 500; |
217 | period = time_on + time_off; | 226 | period = pca963x_period_scale(pca963x, 1000); |
218 | } | 227 | } |
219 | 228 | ||
220 | /* | 229 | /* |
@@ -222,7 +231,7 @@ static int pca963x_blink_set(struct led_classdev *led_cdev, | |||
222 | * (time_on / period) = (GDC / 256) -> | 231 | * (time_on / period) = (GDC / 256) -> |
223 | * GDC = ((time_on * 256) / period) | 232 | * GDC = ((time_on * 256) / period) |
224 | */ | 233 | */ |
225 | gdc = (time_on * 256) / period; | 234 | gdc = (pca963x_period_scale(pca963x, time_on) * 256) / period; |
226 | 235 | ||
227 | /* | 236 | /* |
228 | * From manual: period = ((GFRQ + 1) / 24) in seconds. | 237 | * From manual: period = ((GFRQ + 1) / 24) in seconds. |
@@ -294,6 +303,9 @@ pca963x_dt_init(struct i2c_client *client, struct pca963x_chipdef *chip) | |||
294 | else | 303 | else |
295 | pdata->blink_type = PCA963X_SW_BLINK; | 304 | pdata->blink_type = PCA963X_SW_BLINK; |
296 | 305 | ||
306 | if (of_property_read_u32(np, "nxp,period-scale", &chip->scaling)) | ||
307 | chip->scaling = 1000; | ||
308 | |||
297 | return pdata; | 309 | return pdata; |
298 | } | 310 | } |
299 | 311 | ||