| Message ID | 20191121195902.6906-4-peron.clem@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add support for H6 PWM | expand |
On Thu, Nov 21, 2019 at 08:58:59PM +0100, Clément Péron wrote: > From: Jernej Skrabec <jernej.skrabec@siol.net> > > H6 PWM core needs bus clock to be enabled in order to work. > > Add an optional probe for it. > > Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net> > Signed-off-by: Clément Péron <peron.clem@gmail.com> > --- > drivers/pwm/pwm-sun4i.c | 23 +++++++++++++++++++++++ > 1 file changed, 23 insertions(+) > > diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c > index 369990ae7d09..66befd8d6f9c 100644 > --- a/drivers/pwm/pwm-sun4i.c > +++ b/drivers/pwm/pwm-sun4i.c > @@ -78,6 +78,7 @@ struct sun4i_pwm_data { > > struct sun4i_pwm_chip { > struct pwm_chip chip; > + struct clk *bus_clk; > struct clk *clk; > struct reset_control *rst; > void __iomem *base; > @@ -391,6 +392,14 @@ static int sun4i_pwm_probe(struct platform_device *pdev) > } > } > > + pwm->bus_clk = devm_clk_get_optional(&pdev->dev, "bus"); > + if (IS_ERR(pwm->bus_clk)) { > + if (PTR_ERR(pwm->rst) != -EPROBE_DEFER) > + dev_err(&pdev->dev, "get bus clock failed %pe\n", > + pwm->bus_clk); > + return PTR_ERR(pwm->bus_clk); > + } > + > pwm->rst = devm_reset_control_get_optional_shared(&pdev->dev, NULL); > if (IS_ERR(pwm->rst)) { > if (PTR_ERR(pwm->rst) != -EPROBE_DEFER) > @@ -407,6 +416,17 @@ static int sun4i_pwm_probe(struct platform_device *pdev) > return ret; > } > > + /* > + * We're keeping the bus clock on for the sake of simplicity. > + * Actually it only needs to be on for hardware register accesses. > + */ > + ret = clk_prepare_enable(pwm->bus_clk); > + if (ret) { > + dev_err(&pdev->dev, "Cannot prepare and enable bus_clk %d\n", > + ret); nitpick: other error messages in this driver start with a lower case letter. Until there is an equivalent for %pe that consumes an int, I suggest to use dev_err(&pdev->dev, "Cannot prepare and enable bus_clk: %pe\n", ERR_PTR(ret)); to benefit from a symbolic error name instead of an error constant. Best regards Uwe
Hi Uwe, On Thu, 21 Nov 2019 at 22:06, Uwe Kleine-König <u.kleine-koenig@pengutronix.de> wrote: > > On Thu, Nov 21, 2019 at 08:58:59PM +0100, Clément Péron wrote: > > From: Jernej Skrabec <jernej.skrabec@siol.net> > > > > H6 PWM core needs bus clock to be enabled in order to work. > > > > Add an optional probe for it. > > > > Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net> > > Signed-off-by: Clément Péron <peron.clem@gmail.com> > > --- > > drivers/pwm/pwm-sun4i.c | 23 +++++++++++++++++++++++ > > 1 file changed, 23 insertions(+) > > > > diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c > > index 369990ae7d09..66befd8d6f9c 100644 > > --- a/drivers/pwm/pwm-sun4i.c > > +++ b/drivers/pwm/pwm-sun4i.c > > @@ -78,6 +78,7 @@ struct sun4i_pwm_data { > > > > struct sun4i_pwm_chip { > > struct pwm_chip chip; > > + struct clk *bus_clk; > > struct clk *clk; > > struct reset_control *rst; > > void __iomem *base; > > @@ -391,6 +392,14 @@ static int sun4i_pwm_probe(struct platform_device *pdev) > > } > > } > > > > + pwm->bus_clk = devm_clk_get_optional(&pdev->dev, "bus"); > > + if (IS_ERR(pwm->bus_clk)) { > > + if (PTR_ERR(pwm->rst) != -EPROBE_DEFER) > > + dev_err(&pdev->dev, "get bus clock failed %pe\n", > > + pwm->bus_clk); > > + return PTR_ERR(pwm->bus_clk); > > + } > > + > > pwm->rst = devm_reset_control_get_optional_shared(&pdev->dev, NULL); > > if (IS_ERR(pwm->rst)) { > > if (PTR_ERR(pwm->rst) != -EPROBE_DEFER) > > @@ -407,6 +416,17 @@ static int sun4i_pwm_probe(struct platform_device *pdev) > > return ret; > > } > > > > + /* > > + * We're keeping the bus clock on for the sake of simplicity. > > + * Actually it only needs to be on for hardware register accesses. > > + */ > > + ret = clk_prepare_enable(pwm->bus_clk); > > + if (ret) { > > + dev_err(&pdev->dev, "Cannot prepare and enable bus_clk %d\n", > > + ret); > > nitpick: other error messages in this driver start with a lower case > letter. > > Until there is an equivalent for %pe that consumes an int, I suggest to > use > > dev_err(&pdev->dev, "Cannot prepare and enable bus_clk: %pe\n", > ERR_PTR(ret)); > > to benefit from a symbolic error name instead of an error constant. Ok i will fix both Thanks, Clement > > Best regards > Uwe > > -- > Pengutronix e.K. | Uwe Kleine-König | > Industrial Linux Solutions | https://www.pengutronix.de/ |
diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c index 369990ae7d09..66befd8d6f9c 100644 --- a/drivers/pwm/pwm-sun4i.c +++ b/drivers/pwm/pwm-sun4i.c @@ -78,6 +78,7 @@ struct sun4i_pwm_data { struct sun4i_pwm_chip { struct pwm_chip chip; + struct clk *bus_clk; struct clk *clk; struct reset_control *rst; void __iomem *base; @@ -391,6 +392,14 @@ static int sun4i_pwm_probe(struct platform_device *pdev) } } + pwm->bus_clk = devm_clk_get_optional(&pdev->dev, "bus"); + if (IS_ERR(pwm->bus_clk)) { + if (PTR_ERR(pwm->rst) != -EPROBE_DEFER) + dev_err(&pdev->dev, "get bus clock failed %pe\n", + pwm->bus_clk); + return PTR_ERR(pwm->bus_clk); + } + pwm->rst = devm_reset_control_get_optional_shared(&pdev->dev, NULL); if (IS_ERR(pwm->rst)) { if (PTR_ERR(pwm->rst) != -EPROBE_DEFER) @@ -407,6 +416,17 @@ static int sun4i_pwm_probe(struct platform_device *pdev) return ret; } + /* + * We're keeping the bus clock on for the sake of simplicity. + * Actually it only needs to be on for hardware register accesses. + */ + ret = clk_prepare_enable(pwm->bus_clk); + if (ret) { + dev_err(&pdev->dev, "Cannot prepare and enable bus_clk %d\n", + ret); + goto err_bus; + } + pwm->chip.dev = &pdev->dev; pwm->chip.ops = &sun4i_pwm_ops; pwm->chip.base = -1; @@ -427,6 +447,8 @@ static int sun4i_pwm_probe(struct platform_device *pdev) return 0; err_pwm_add: + clk_disable_unprepare(pwm->bus_clk); +err_bus: reset_control_assert(pwm->rst); return ret; @@ -441,6 +463,7 @@ static int sun4i_pwm_remove(struct platform_device *pdev) if (ret) return ret; + clk_disable_unprepare(pwm->bus_clk); reset_control_assert(pwm->rst); return 0;