| Message ID | 20191118093727.21899-4-peron.clem@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Add support for H6 PWM | expand |
On Mon, Nov 18, 2019 at 10:37:22AM +0100, Clément Péron wrote: > New device tree bindings called the source clock of the module > "mod" when several clocks are defined. > > Try to get a clock called "mod" if nothing is found try to get > an unnamed clock. > > Signed-off-by: Clément Péron <peron.clem@gmail.com> > --- > drivers/pwm/pwm-sun4i.c | 29 +++++++++++++++++++++++++++-- > 1 file changed, 27 insertions(+), 2 deletions(-) > > diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c > index c17935805690..bbb1ed194c0e 100644 > --- a/drivers/pwm/pwm-sun4i.c > +++ b/drivers/pwm/pwm-sun4i.c > @@ -362,9 +362,34 @@ static int sun4i_pwm_probe(struct platform_device *pdev) > if (IS_ERR(pwm->base)) > return PTR_ERR(pwm->base); > > - pwm->clk = devm_clk_get(&pdev->dev, NULL); > - if (IS_ERR(pwm->clk)) > + /* > + * All hardware variants need a source clock that is divided and > + * then feeds the counter that defines the output wave form. In the > + * device tree this clock is either unnamed or called "mod". > + * Some variants (e.g. H6) need another clock to access the > + * hardware registers; this is called "bus". > + * So we request "mod" first (and ignore the corner case that a > + * parent provides a "mod" clock while the right one would be the > + * unnamed one of the PWM device) and if this is not found we fall > + * back to the first clock of the PWM. > + */ > + pwm->clk = devm_clk_get_optional(&pdev->dev, "mod"); > + if (IS_ERR(pwm->clk)) { > + if (PTR_ERR(pwm->rst) != -EPROBE_DEFER) > + dev_err(&pdev->dev, "get clock failed %pe\n", > + pwm->clk); I think the line break isn't needed here. Unless I'm mistaken the final ; will end in column 80 which is fine. > return PTR_ERR(pwm->clk); > + } > + > + if (!pwm->clk) { > + pwm->clk = devm_clk_get(&pdev->dev, NULL); > + if (IS_ERR(pwm->clk)) { > + if (PTR_ERR(pwm->rst) != -EPROBE_DEFER) > + dev_err(&pdev->dev, "get clock failed %pe\n", > + pwm->clk); A different error message than above would be nice to be able to distinguish the two cases. Best regards Uwe
diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c index c17935805690..bbb1ed194c0e 100644 --- a/drivers/pwm/pwm-sun4i.c +++ b/drivers/pwm/pwm-sun4i.c @@ -362,9 +362,34 @@ static int sun4i_pwm_probe(struct platform_device *pdev) if (IS_ERR(pwm->base)) return PTR_ERR(pwm->base); - pwm->clk = devm_clk_get(&pdev->dev, NULL); - if (IS_ERR(pwm->clk)) + /* + * All hardware variants need a source clock that is divided and + * then feeds the counter that defines the output wave form. In the + * device tree this clock is either unnamed or called "mod". + * Some variants (e.g. H6) need another clock to access the + * hardware registers; this is called "bus". + * So we request "mod" first (and ignore the corner case that a + * parent provides a "mod" clock while the right one would be the + * unnamed one of the PWM device) and if this is not found we fall + * back to the first clock of the PWM. + */ + pwm->clk = devm_clk_get_optional(&pdev->dev, "mod"); + if (IS_ERR(pwm->clk)) { + if (PTR_ERR(pwm->rst) != -EPROBE_DEFER) + dev_err(&pdev->dev, "get clock failed %pe\n", + pwm->clk); return PTR_ERR(pwm->clk); + } + + if (!pwm->clk) { + pwm->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(pwm->clk)) { + if (PTR_ERR(pwm->rst) != -EPROBE_DEFER) + dev_err(&pdev->dev, "get clock failed %pe\n", + pwm->clk); + return PTR_ERR(pwm->clk); + } + } pwm->rst = devm_reset_control_get_optional_shared(&pdev->dev, NULL); if (IS_ERR(pwm->rst)) {
New device tree bindings called the source clock of the module "mod" when several clocks are defined. Try to get a clock called "mod" if nothing is found try to get an unnamed clock. Signed-off-by: Clément Péron <peron.clem@gmail.com> --- drivers/pwm/pwm-sun4i.c | 29 +++++++++++++++++++++++++++-- 1 file changed, 27 insertions(+), 2 deletions(-)