Re: [PATCH v3 6/6] hwmon: pwm-fan: Update the duty cycle inorder to control the pwm-fan

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




On 04/12/2015 08:29 AM, Anand Moon wrote:
hi Guenter,

I am referring to #linux/drivers/pwm/pwm-samsung.c

Will update the comment.

Sure, but that doesn't help as patch description for the pwm-fan driver.

Guenter

-Anand Moon

On 12 April 2015 at 20:37, Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
On 04/12/2015 07:54 AM, Anand Moon wrote:

In order to disable the PWM we need to update using following sequence.

         pwm_config(pwm, 0, period);
         pwm_disable(pwm);

pwm_config() with a zero duty cycle to make it clear the timer and update
the PWM registers.
pwm_disable will clear the TCON_AUTORELOAD(tcon_chan) and update the PWM
register.

There is no TCON_AUTORELOAD in this driver. Future developers will have no
idea
what you are talking about here. Please provide a generic comment.

Next change in state will get trigger unless a new PWM cycle happened.

That sentence is difficult to parse. Actually, I have no idea what it is
supposed to mean.

         pwm_config(pwm, duty, period);
         pwm_enable(pwm);

Through pwm_config we update the duty cycle and period and update the PWM
register.
pwm_enable will update the state to TCON_MANUALUPDATE(tcon_chan)
and TCON_START(tcon_chan) | TCON_AUTORELOAD(tcon_chan) and update the PWM
register.

This sentence does not make sense in the context of the pwm-fan driver.

Reported-by: Markus Reichl <m.reichl@xxxxxxxxxxxxx>
Tested-by: Markus Reichl <m.reichl@xxxxxxxxxxxxx>
Reviewed-by: Lukasz Majewski <l.majewski@xxxxxxxxxxx>
Reviewed-by: Sjoerd Simons <sjoerd.simons@xxxxxxxxxxxxxxx>
Signed-off-by: Anand Moon <linux.amoon@xxxxxxxxx>
---
   drivers/hwmon/pwm-fan.c | 10 ++++------
   1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c
index 7c83dc4..f25c841 100644
--- a/drivers/hwmon/pwm-fan.c
+++ b/drivers/hwmon/pwm-fan.c
@@ -44,26 +44,24 @@ static int  __set_pwm(struct pwm_fan_ctx *ctx,
unsigned long pwm)
         int ret = 0;

         mutex_lock(&ctx->lock);
+


Please refrain from making unnecessary whitespace changes.

Thanks,
Guenter



--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]
  Powered by Linux