| Message ID | 1464942192-25967-9-git-send-email-boris.brezillon@free-electrons.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Jun 03, 2016 at 10:23:06AM +0200, Boris Brezillon wrote: > The current logic will disable the PWM clk even if a PWM was left > enabled by the bootloader (because it's controlling a critical device > like a regulator for example). > Keep the PWM clk enabled if at least one PWM is enabled to avoid any > glitches. > > Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> > --- > drivers/pwm/pwm-sti.c | 17 +++++++++++++++-- > 1 file changed, 15 insertions(+), 2 deletions(-) > > diff --git a/drivers/pwm/pwm-sti.c b/drivers/pwm/pwm-sti.c > index 6300d3e..8232c5b 100644 > --- a/drivers/pwm/pwm-sti.c > +++ b/drivers/pwm/pwm-sti.c > @@ -340,7 +340,7 @@ static int sti_pwm_probe(struct platform_device *pdev) > struct sti_pwm_compat_data *cdata; > struct sti_pwm_chip *pc; > struct resource *res; > - int ret; > + int i, ret; > > pc = devm_kzalloc(dev, sizeof(*pc), GFP_KERNEL); > if (!pc) > @@ -391,7 +391,7 @@ static int sti_pwm_probe(struct platform_device *pdev) > return -EINVAL; > } > > - ret = clk_prepare(pc->clk); > + ret = clk_prepare_enable(pc->clk); > if (ret) { > dev_err(dev, "failed to prepare clock\n"); > return ret; > @@ -409,6 +409,19 @@ static int sti_pwm_probe(struct platform_device *pdev) > return ret; > } > > + /* > + * Keep the PWM clk enabled if some PWMs appear to be up and > + * running. > + */ > + for (i = 0; i < pc->chip.npwm; i++) { > + struct pwm_state state; > + > + pwm_get_state(&pc->chip.pwms[i], &state); > + if (state.enabled) Similar to pwm-rockchip: you could just do if (pwm_is_enabled(...)). Brian > + clk_enable(pc->clk); > + } > + clk_disable(pc->clk); > + > platform_set_drvdata(pdev, pc); > > return 0; > -- > 2.7.4 >
diff --git a/drivers/pwm/pwm-sti.c b/drivers/pwm/pwm-sti.c index 6300d3e..8232c5b 100644 --- a/drivers/pwm/pwm-sti.c +++ b/drivers/pwm/pwm-sti.c @@ -340,7 +340,7 @@ static int sti_pwm_probe(struct platform_device *pdev) struct sti_pwm_compat_data *cdata; struct sti_pwm_chip *pc; struct resource *res; - int ret; + int i, ret; pc = devm_kzalloc(dev, sizeof(*pc), GFP_KERNEL); if (!pc) @@ -391,7 +391,7 @@ static int sti_pwm_probe(struct platform_device *pdev) return -EINVAL; } - ret = clk_prepare(pc->clk); + ret = clk_prepare_enable(pc->clk); if (ret) { dev_err(dev, "failed to prepare clock\n"); return ret; @@ -409,6 +409,19 @@ static int sti_pwm_probe(struct platform_device *pdev) return ret; } + /* + * Keep the PWM clk enabled if some PWMs appear to be up and + * running. + */ + for (i = 0; i < pc->chip.npwm; i++) { + struct pwm_state state; + + pwm_get_state(&pc->chip.pwms[i], &state); + if (state.enabled) + clk_enable(pc->clk); + } + clk_disable(pc->clk); + platform_set_drvdata(pdev, pc); return 0;
The current logic will disable the PWM clk even if a PWM was left enabled by the bootloader (because it's controlling a critical device like a regulator for example). Keep the PWM clk enabled if at least one PWM is enabled to avoid any glitches. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> --- drivers/pwm/pwm-sti.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-)