summaryrefslogtreecommitdiff
path: root/include/linux/pwm.h
diff options
context:
space:
mode:
authorMauro Carvalho Chehab <mchehab@s-opensource.com>2016-07-23 07:59:19 -0300
committerMauro Carvalho Chehab <mchehab@s-opensource.com>2016-07-23 07:59:19 -0300
commitc278256d05a2fc75b427fa6a5dc0024faa93465d (patch)
tree2c09c6c65a4b6c597a568ec2425adb75eff7d5d5 /include/linux/pwm.h
parent7e5b7d1b3a8facd4dc1ddb5d9ec53c0687d13de7 (diff)
parent009a620848218d521f008141c62f56bf19294dd9 (diff)
Merge branch 'patchwork' into topic/docs-next
* patchwork: (1492 commits) [media] cec: always check all_device_types and features [media] cec: poll should check if there is room in the tx queue [media] vivid: support monitor all mode [media] cec: fix test for unconfigured adapter in main message loop [media] cec: limit the size of the transmit queue [media] cec: zero unused msg part after msg->len [media] cec: don't set fh to NULL in CEC_TRANSMIT [media] cec: clear all status fields before transmit and always fill in sequence [media] cec: CEC_RECEIVE overwrote the timeout field [media] cxd2841er: Reading SNR for DVB-C added [media] cxd2841er: Reading BER and UCB for DVB-C added [media] cxd2841er: fix switch-case for DVB-C [media] cxd2841er: fix signal strength scale for ISDB-T [media] cxd2841er: adjust the dB scale for DVB-C [media] cxd2841er: provide signal strength for DVB-C [media] cxd2841er: fix BER report via DVBv5 stats API [media] mb86a20s: apply mask to val after checking for read failure [media] airspy: fix error logic during device register [media] s5p-cec/TODO: add TODO item [media] cec/TODO: drop comment about sphinx documentation ... Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Diffstat (limited to 'include/linux/pwm.h')
-rw-r--r--include/linux/pwm.h19
1 files changed, 13 insertions, 6 deletions
diff --git a/include/linux/pwm.h b/include/linux/pwm.h
index 17018f3c066e..c038ae36b10e 100644
--- a/include/linux/pwm.h
+++ b/include/linux/pwm.h
@@ -235,6 +235,9 @@ static inline int pwm_config(struct pwm_device *pwm, int duty_ns,
if (!pwm)
return -EINVAL;
+ if (duty_ns < 0 || period_ns < 0)
+ return -EINVAL;
+
pwm_get_state(pwm, &state);
if (state.duty_cycle == duty_ns && state.period == period_ns)
return 0;
@@ -461,6 +464,8 @@ static inline bool pwm_can_sleep(struct pwm_device *pwm)
static inline void pwm_apply_args(struct pwm_device *pwm)
{
+ struct pwm_state state = { };
+
/*
* PWM users calling pwm_apply_args() expect to have a fresh config
* where the polarity and period are set according to pwm_args info.
@@ -473,18 +478,20 @@ static inline void pwm_apply_args(struct pwm_device *pwm)
* at startup (even if they are actually enabled), thus authorizing
* polarity setting.
*
- * Instead of setting ->enabled to false, we call pwm_disable()
- * before pwm_set_polarity() to ensure that everything is configured
- * as expected, and the PWM is really disabled when the user request
- * it.
+ * To fulfill this requirement, we apply a new state which disables
+ * the PWM device and set the reference period and polarity config.
*
* Note that PWM users requiring a smooth handover between the
* bootloader and the kernel (like critical regulators controlled by
* PWM devices) will have to switch to the atomic API and avoid calling
* pwm_apply_args().
*/
- pwm_disable(pwm);
- pwm_set_polarity(pwm, pwm->args.polarity);
+
+ state.enabled = false;
+ state.polarity = pwm->args.polarity;
+ state.period = pwm->args.period;
+
+ pwm_apply_state(pwm, &state);
}
struct pwm_lookup {