Message ID | 2c5abe6578c8e4e841cb59357d88ce397551a593.1475571575.git.mylene.josserand@free-electrons.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Hello, On Tue, 4 Oct 2016 11:46:16 +0200, Mylène Josserand wrote: > #include <sound/dmaengine_pcm.h> > #include <sound/pcm_params.h> > @@ -589,6 +590,7 @@ static int sun4i_i2s_probe(struct platform_device *pdev) > { > struct sun4i_i2s *i2s; > struct resource *res; > + struct reset_control *reset_apb; > void __iomem *regs; > int irq, ret; > > @@ -626,7 +628,19 @@ static int sun4i_i2s_probe(struct platform_device *pdev) > dev_err(&pdev->dev, "Can't get our mod clock\n"); > return PTR_ERR(i2s->mod_clk); > } > - > + > + reset_apb = devm_reset_control_get(&pdev->dev, "apb_reset"); I believe this is a change in the Device Tree binding, since you're adding support for a new resource. Perhaps the Device Tree binding documentation should be updated accordingly? > + if (IS_ERR(reset_apb)) { > + dev_err(&pdev->dev, "Can't get apb reset\n"); > + return PTR_ERR(i2s->mod_clk); This should be: return PTR_ERR(reset_apb); > + } > + > + ret = reset_control_deassert(reset_apb); > + if (ret < 0) { > + dev_err(&pdev->dev, "Can't deassert apb reset (%d)\n", ret); > + return ret; > + } Do you need to re-assert the reset line in the ->remove() hook? Best regards, Thomas
On 4 October 2016 at 11:46, Mylène Josserand <mylene.josserand@free-electrons.com> wrote: > Add APB deassert function for sun4i-i2s driver. > > Signed-off-by: Mylène Josserand <mylene.josserand@free-electrons.com> > --- > sound/soc/sunxi/sun4i-i2s.c | 16 +++++++++++++++- > 1 file changed, 15 insertions(+), 1 deletion(-) > > diff --git a/sound/soc/sunxi/sun4i-i2s.c b/sound/soc/sunxi/sun4i-i2s.c > index 687a8f8..f3f7026 100644 > --- a/sound/soc/sunxi/sun4i-i2s.c > +++ b/sound/soc/sunxi/sun4i-i2s.c > @@ -17,6 +17,7 @@ > #include <linux/platform_device.h> > #include <linux/pm_runtime.h> > #include <linux/regmap.h> > +#include <linux/reset.h> > > #include <sound/dmaengine_pcm.h> > #include <sound/pcm_params.h> > @@ -589,6 +590,7 @@ static int sun4i_i2s_probe(struct platform_device *pdev) > { > struct sun4i_i2s *i2s; > struct resource *res; > + struct reset_control *reset_apb; > void __iomem *regs; > int irq, ret; > > @@ -626,7 +628,19 @@ static int sun4i_i2s_probe(struct platform_device *pdev) > dev_err(&pdev->dev, "Can't get our mod clock\n"); > return PTR_ERR(i2s->mod_clk); > } > - > + > + reset_apb = devm_reset_control_get(&pdev->dev, "apb_reset"); > + if (IS_ERR(reset_apb)) { > + dev_err(&pdev->dev, "Can't get apb reset\n"); > + return PTR_ERR(i2s->mod_clk); > + } > + > + ret = reset_control_deassert(reset_apb); > + if (ret < 0) { > + dev_err(&pdev->dev, "Can't deassert apb reset (%d)\n", ret); > + return ret; > + } > + Is this functionality only required for A31 and onwards?, CK > i2s->playback_dma_data.addr = res->start + SUN4I_I2S_FIFO_TX_REG; > i2s->playback_dma_data.maxburst = 4; > > -- > 2.9.3 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Hi, On Tue, Oct 04, 2016 at 02:15:16PM +0200, Thomas Petazzoni wrote: > Hello, > > On Tue, 4 Oct 2016 11:46:16 +0200, Mylène Josserand wrote: > > > #include <sound/dmaengine_pcm.h> > > #include <sound/pcm_params.h> > > @@ -589,6 +590,7 @@ static int sun4i_i2s_probe(struct platform_device *pdev) > > { > > struct sun4i_i2s *i2s; > > struct resource *res; > > + struct reset_control *reset_apb; > > void __iomem *regs; > > int irq, ret; > > > > @@ -626,7 +628,19 @@ static int sun4i_i2s_probe(struct platform_device *pdev) > > dev_err(&pdev->dev, "Can't get our mod clock\n"); > > return PTR_ERR(i2s->mod_clk); > > } > > - > > + > > + reset_apb = devm_reset_control_get(&pdev->dev, "apb_reset"); > > I believe this is a change in the Device Tree binding, since you're > adding support for a new resource. Perhaps the Device Tree binding > documentation should be updated accordingly? Indeed. You have two solutions to do that: - Either mark it as optional and use reset_control_get_optional (because here, you broke the other SoCs that have that controller but no reset line) - Or introduce a new compatible, and make the reset property mandatory for that new compatible. I prefer the latter, since you get a stricter error check, and you cannot end up in a situation where your driver probes but is useless. But you'll find both in our drivers. > > + } > > + > > + ret = reset_control_deassert(reset_apb); > > + if (ret < 0) { > > + dev_err(&pdev->dev, "Can't deassert apb reset (%d)\n", ret); > > + return ret; > > + } > > Do you need to re-assert the reset line in the ->remove() hook? Even better, you can add it to the runtime_pm hooks! :) Maxime
Hello, On 04/10/2016 17:42, Maxime Ripard wrote: > Hi, > > On Tue, Oct 04, 2016 at 02:15:16PM +0200, Thomas Petazzoni wrote: >> Hello, >> >> On Tue, 4 Oct 2016 11:46:16 +0200, Mylène Josserand wrote: >> >>> #include <sound/dmaengine_pcm.h> >>> #include <sound/pcm_params.h> >>> @@ -589,6 +590,7 @@ static int sun4i_i2s_probe(struct platform_device *pdev) >>> { >>> struct sun4i_i2s *i2s; >>> struct resource *res; >>> + struct reset_control *reset_apb; >>> void __iomem *regs; >>> int irq, ret; >>> >>> @@ -626,7 +628,19 @@ static int sun4i_i2s_probe(struct platform_device *pdev) >>> dev_err(&pdev->dev, "Can't get our mod clock\n"); >>> return PTR_ERR(i2s->mod_clk); >>> } >>> - >>> + >>> + reset_apb = devm_reset_control_get(&pdev->dev, "apb_reset"); >> >> I believe this is a change in the Device Tree binding, since you're >> adding support for a new resource. Perhaps the Device Tree binding >> documentation should be updated accordingly? > > Indeed. > > You have two solutions to do that: > - Either mark it as optional and use reset_control_get_optional > (because here, you broke the other SoCs that have that controller > but no reset line) > - Or introduce a new compatible, and make the reset property > mandatory for that new compatible. > > I prefer the latter, since you get a stricter error check, and you > cannot end up in a situation where your driver probes but is > useless. But you'll find both in our drivers. > Okay, thank you for the hints! >>> + } >>> + >>> + ret = reset_control_deassert(reset_apb); >>> + if (ret < 0) { >>> + dev_err(&pdev->dev, "Can't deassert apb reset (%d)\n", ret); >>> + return ret; >>> + } >> >> Do you need to re-assert the reset line in the ->remove() hook? > > Even better, you can add it to the runtime_pm hooks! :) I will have a look to runtime_pm and update it for a V2.
diff --git a/sound/soc/sunxi/sun4i-i2s.c b/sound/soc/sunxi/sun4i-i2s.c index 687a8f8..f3f7026 100644 --- a/sound/soc/sunxi/sun4i-i2s.c +++ b/sound/soc/sunxi/sun4i-i2s.c @@ -17,6 +17,7 @@ #include <linux/platform_device.h> #include <linux/pm_runtime.h> #include <linux/regmap.h> +#include <linux/reset.h> #include <sound/dmaengine_pcm.h> #include <sound/pcm_params.h> @@ -589,6 +590,7 @@ static int sun4i_i2s_probe(struct platform_device *pdev) { struct sun4i_i2s *i2s; struct resource *res; + struct reset_control *reset_apb; void __iomem *regs; int irq, ret; @@ -626,7 +628,19 @@ static int sun4i_i2s_probe(struct platform_device *pdev) dev_err(&pdev->dev, "Can't get our mod clock\n"); return PTR_ERR(i2s->mod_clk); } - + + reset_apb = devm_reset_control_get(&pdev->dev, "apb_reset"); + if (IS_ERR(reset_apb)) { + dev_err(&pdev->dev, "Can't get apb reset\n"); + return PTR_ERR(i2s->mod_clk); + } + + ret = reset_control_deassert(reset_apb); + if (ret < 0) { + dev_err(&pdev->dev, "Can't deassert apb reset (%d)\n", ret); + return ret; + } + i2s->playback_dma_data.addr = res->start + SUN4I_I2S_FIFO_TX_REG; i2s->playback_dma_data.maxburst = 4;
Add APB deassert function for sun4i-i2s driver. Signed-off-by: Mylène Josserand <mylene.josserand@free-electrons.com> --- sound/soc/sunxi/sun4i-i2s.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-)