[PATCH 0/2] pwm fixes for 3.8

[PATCH 0/2] pwm fixes for 3.8

[Tony Prisk]

Hi Theirry,

As discussed, here is the patch to correct the issue created by enabling
disabling the pwm clock during pwm_enable/_disable. A second patch is
including which fixes a build error introduced in the same patch.

These should be applied on top of the previous patch.

Tony Prisk (2):
  Fix build error in pwm-vt8500.c
  pwm: vt8500: Ensure pwm clock is enabled during pwm_config

 drivers/pwm/pwm-vt8500.c |    9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

-- 
1.7.9.5

[PATCH 1/2] Fix build error in pwm-vt8500.c

[Tony Prisk]

A missing '{' causes a build error in pwm-vt8500.c

Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
---
 drivers/pwm/pwm-vt8500.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pwm/pwm-vt8500.c b/drivers/pwm/pwm-vt8500.c
index 970b0c6..806f72c 100644
--- a/drivers/pwm/pwm-vt8500.c
+++ b/drivers/pwm/pwm-vt8500.c
@@ -100,7 +100,7 @@ static int vt8500_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 	struct vt8500_chip *vt8500 = to_vt8500_chip(chip);
 
 	err = clk_enable(vt8500->clk);
-	if (err < 0)
+	if (err < 0) {
 		dev_err(chip->dev, "failed to enable clock\n");
 		return err;
 	};
-- 
1.7.9.5

[PATCH 2/2] pwm: vt8500: Ensure pwm clock is enabled during pwm_config

[Tony Prisk]

When all PWMs are disabled, PWM module may be disabled during
calls to pwm_config. This patch enables/disables the clock in
pwm_config to ensure the module is active before register read/
writes.

Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
---
 drivers/pwm/pwm-vt8500.c |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/pwm/pwm-vt8500.c b/drivers/pwm/pwm-vt8500.c
index 806f72c..cc97af9 100644
--- a/drivers/pwm/pwm-vt8500.c
+++ b/drivers/pwm/pwm-vt8500.c
@@ -63,6 +63,8 @@ static int vt8500_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	unsigned long long c;
 	unsigned long period_cycles, prescale, pv, dc;
 
+	clk_enable(vt8500->clk);
+
 	c = clk_get_rate(vt8500->clk);
 	c = c * period_ns;
 	do_div(c, 1000000000);
@@ -75,8 +77,10 @@ static int vt8500_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	if (pv > 4095)
 		pv = 4095;
 
-	if (prescale > 1023)
+	if (prescale > 1023) {
+		clk_disable(vt8500->clk);
 		return -EINVAL;
+	}
 
 	c = (unsigned long long)pv * duty_ns;
 	do_div(c, period_ns);
@@ -91,6 +95,7 @@ static int vt8500_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	pwm_busy_wait(vt8500->base + 0x40 + pwm->hwpwm, (1 << 3));
 	writel(dc, vt8500->base + 0xc + (pwm->hwpwm << 4));
 
+	clk_disable(vt8500->clk);
 	return 0;
 }
 
-- 
1.7.9.5

[PATCH 1/2] Fix build error in pwm-vt8500.c

[Thierry Reding]

On Mon, Nov 19, 2012 at 03:06:19PM +1300, Tony Prisk wrote:
> A missing '{' causes a build error in pwm-vt8500.c

Great, how embarrassing. You've just uncovered a typo in my automated
build test setup. =)

Thierry
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[PATCH 2/2] pwm: vt8500: Ensure pwm clock is enabled during pwm_config

[Thierry Reding]

On Mon, Nov 19, 2012 at 03:06:20PM +1300, Tony Prisk wrote:
> When all PWMs are disabled, PWM module may be disabled during
> calls to pwm_config. This patch enables/disables the clock in
> pwm_config to ensure the module is active before register read/
> writes.
> 
> Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
> ---
>  drivers/pwm/pwm-vt8500.c |    7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pwm/pwm-vt8500.c b/drivers/pwm/pwm-vt8500.c
> index 806f72c..cc97af9 100644
> --- a/drivers/pwm/pwm-vt8500.c
> +++ b/drivers/pwm/pwm-vt8500.c
> @@ -63,6 +63,8 @@ static int vt8500_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
>  	unsigned long long c;
>  	unsigned long period_cycles, prescale, pv, dc;
>  
> +	clk_enable(vt8500->clk);

This needs a check of the return value. Other than that, looks good.

Thierry
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[PATCH 1/2] Fix build error in pwm-vt8500.c

[Russell King - ARM Linux]

On Mon, Nov 19, 2012 at 03:06:19PM +1300, Tony Prisk wrote:
> A missing '{' causes a build error in pwm-vt8500.c
> 
> Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
> ---
>  drivers/pwm/pwm-vt8500.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/pwm/pwm-vt8500.c b/drivers/pwm/pwm-vt8500.c
> index 970b0c6..806f72c 100644
> --- a/drivers/pwm/pwm-vt8500.c
> +++ b/drivers/pwm/pwm-vt8500.c
> @@ -100,7 +100,7 @@ static int vt8500_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
>  	struct vt8500_chip *vt8500 = to_vt8500_chip(chip);
>  
>  	err = clk_enable(vt8500->clk);
> -	if (err < 0)
> +	if (err < 0) {
>  		dev_err(chip->dev, "failed to enable clock\n");
>  		return err;
>  	};

Why does this closing brace have a semicolon after it?

[PATCH 1/2] Fix build error in pwm-vt8500.c

[Thierry Reding]

On Mon, Nov 19, 2012 at 09:29:26AM +0000, Russell King - ARM Linux wrote:
> On Mon, Nov 19, 2012 at 03:06:19PM +1300, Tony Prisk wrote:
> > A missing '{' causes a build error in pwm-vt8500.c
> > 
> > Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
> > ---
> >  drivers/pwm/pwm-vt8500.c |    2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/pwm/pwm-vt8500.c b/drivers/pwm/pwm-vt8500.c
> > index 970b0c6..806f72c 100644
> > --- a/drivers/pwm/pwm-vt8500.c
> > +++ b/drivers/pwm/pwm-vt8500.c
> > @@ -100,7 +100,7 @@ static int vt8500_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
> >  	struct vt8500_chip *vt8500 = to_vt8500_chip(chip);
> >  
> >  	err = clk_enable(vt8500->clk);
> > -	if (err < 0)
> > +	if (err < 0) {
> >  		dev_err(chip->dev, "failed to enable clock\n");
> >  		return err;
> >  	};
> 
> Why does this closing brace have a semicolon after it?

Tony,

can you remove the gratuitous semicolon while at it, please?

Thanks for spotting it Russell.

Thierry
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