[PATCH v3 0/2] pwm fixes for 3.8

[PATCH v3 0/2] pwm fixes for 3.8

[Tony Prisk]

Hi Theirry,

I felt the error message for clk_enable in vt8500_pwm_config() needed
to somehow indicate that the clk_enable failed in this function otherwise
if there is a problem, you can't tell which of the clk_enable's
generated the fail message.
If there is a clock error - as you pointed out - it will probably fail
elsewhere as well so I've changed it to match the other error messages.

These should be applied on top of the original patch.

v2: Add error checking for clk_enable()
v3: Remove superfluous ;'s. Error message style correction.

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 |   16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

-- 
1.7.9.5

[PATCH v3 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 v3 2/2] pwm: vt8500: Ensure pwm clock is enabled during pwm_config

[Tony Prisk]

This patch corrects a bug reported by Peter Vasil.

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>
Tested-by: Peter Vasil <petervasil@gmail.com>
---
 drivers/pwm/pwm-vt8500.c |   14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/pwm/pwm-vt8500.c b/drivers/pwm/pwm-vt8500.c
index 806f72c..b0ba2d4 100644
--- a/drivers/pwm/pwm-vt8500.c
+++ b/drivers/pwm/pwm-vt8500.c
@@ -62,6 +62,13 @@ static int vt8500_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	struct vt8500_chip *vt8500 = to_vt8500_chip(chip);
 	unsigned long long c;
 	unsigned long period_cycles, prescale, pv, dc;
+	int err;
+
+	err = clk_enable(vt8500->clk);
+	if (err < 0) {
+		dev_err(chip->dev, "failed to enable clock\n");
+		return err;
+	}
 
 	c = clk_get_rate(vt8500->clk);
 	c = c * period_ns;
@@ -75,8 +82,10 @@ 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 +100,7 @@ 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;
 }
 
@@ -103,7 +113,7 @@ static int vt8500_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
 	if (err < 0) {
 		dev_err(chip->dev, "failed to enable clock\n");
 		return err;
-	};
+	}
 
 	pwm_busy_wait(vt8500->base + 0x40 + pwm->hwpwm, (1 << 0));
 	writel(5, vt8500->base + (pwm->hwpwm << 4));
-- 
1.7.9.5

[PATCH v3 0/2] pwm fixes for 3.8

[Thierry Reding]

On Tue, Nov 20, 2012 at 06:44:44AM +1300, Tony Prisk wrote:
> Hi Theirry,
> 
> I felt the error message for clk_enable in vt8500_pwm_config() needed
> to somehow indicate that the clk_enable failed in this function otherwise
> if there is a problem, you can't tell which of the clk_enable's
> generated the fail message.
> If there is a clock error - as you pointed out - it will probably fail
> elsewhere as well so I've changed it to match the other error messages.
> 
> These should be applied on top of the original patch.
> 
> v2: Add error checking for clk_enable()
> v3: Remove superfluous ;'s. Error message style correction.
> 
> 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 |   16 +++++++++++++---
>  1 file changed, 13 insertions(+), 3 deletions(-)

Applied with minor stylistic fixups to the commit message, thanks.

Thierry
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