| Message ID | 1551284609-14594-7-git-send-email-claudiu.beznea@microchip.com |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | add LCD support for SAM9X60 | expand |
Hi Claudiu On Wed, Feb 27, 2019 at 04:24:40PM +0000, Claudiu.Beznea@microchip.com wrote: > From: Sandeep Sheriker Mallikarjun <sandeepsheriker.mallikarjun@microchip.com> > > For SAM9X60 SoC, sys_clk is through lcd_gclk clock source and this > needs to be enabled before enabling lcd_clk. We have "ownership" of the clocks in the mfd device. So it would make more sense to let the mfd device handle the base clocks. In other words - what about pushing enable of perigh_clk and sys_clk to the mfd driver. This may have the nice side-effect that we avoid that both the drm driver and the pwm driver enable/disable the periph_clk as it is today. Another comment - fixed_clksrc is used to determine if sys_clk is enabled. But that flag is about the clksource selection, and it is just a coincidence that the same flag can be used here. Why we cannot always enable sys_clk? Do we need to do this only for sam9x60? IF yes, then add a new falg. If no, then skip the flag. Sam > > Signed-off-by: Sandeep Sheriker Mallikarjun <sandeepsheriker.mallikarjun@microchip.com> > [claudiu.beznea@microchip.com: add fixed_clksrc checks] > Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> > --- > drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c | 19 ++++++++++++++++++- > 1 file changed, 18 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c > index 0be13eceedba..8bf51f853721 100644 > --- a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c > +++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c > @@ -625,10 +625,18 @@ static int atmel_hlcdc_dc_load(struct drm_device *dev) > dc->hlcdc = dev_get_drvdata(dev->dev->parent); > dev->dev_private = dc; > > + if (dc->desc->fixed_clksrc) { > + ret = clk_prepare_enable(dc->hlcdc->sys_clk); > + if (ret) { > + dev_err(dev->dev, "failed to enable sys_clk\n"); > + goto err_destroy_wq; > + } > + } > + > ret = clk_prepare_enable(dc->hlcdc->periph_clk); > if (ret) { > dev_err(dev->dev, "failed to enable periph_clk\n"); > - goto err_destroy_wq; > + goto err_sys_clk_disable; > } > > pm_runtime_enable(dev->dev); > @@ -664,6 +672,9 @@ static int atmel_hlcdc_dc_load(struct drm_device *dev) > err_periph_clk_disable: > pm_runtime_disable(dev->dev); > clk_disable_unprepare(dc->hlcdc->periph_clk); > +err_sys_clk_disable: > + if (dc->desc->fixed_clksrc) > + clk_disable_unprepare(dc->hlcdc->sys_clk); > > err_destroy_wq: > destroy_workqueue(dc->wq); > @@ -688,6 +699,8 @@ static void atmel_hlcdc_dc_unload(struct drm_device *dev) > > pm_runtime_disable(dev->dev); > clk_disable_unprepare(dc->hlcdc->periph_clk); > + if (dc->desc->fixed_clksrc) > + clk_disable_unprepare(dc->hlcdc->sys_clk); > destroy_workqueue(dc->wq); > } > > @@ -805,6 +818,8 @@ static int atmel_hlcdc_dc_drm_suspend(struct device *dev) > regmap_read(regmap, ATMEL_HLCDC_IMR, &dc->suspend.imr); > regmap_write(regmap, ATMEL_HLCDC_IDR, dc->suspend.imr); > clk_disable_unprepare(dc->hlcdc->periph_clk); > + if (dc->desc->fixed_clksrc) > + clk_disable_unprepare(dc->hlcdc->sys_clk); > > return 0; > } > @@ -814,6 +829,8 @@ static int atmel_hlcdc_dc_drm_resume(struct device *dev) > struct drm_device *drm_dev = dev_get_drvdata(dev); > struct atmel_hlcdc_dc *dc = drm_dev->dev_private; > > + if (dc->desc->fixed_clksrc) > + clk_prepare_enable(dc->hlcdc->sys_clk); > clk_prepare_enable(dc->hlcdc->periph_clk); > regmap_write(dc->hlcdc->regmap, ATMEL_HLCDC_IER, dc->suspend.imr); > > -- > 2.7.4 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel
On 28.02.2019 23:55, Sam Ravnborg wrote: > Hi Claudiu > > On Wed, Feb 27, 2019 at 04:24:40PM +0000, Claudiu.Beznea@microchip.com wrote: >> From: Sandeep Sheriker Mallikarjun <sandeepsheriker.mallikarjun@microchip.com> >> >> For SAM9X60 SoC, sys_clk is through lcd_gclk clock source and this >> needs to be enabled before enabling lcd_clk. > > We have "ownership" of the clocks in the mfd device. > So it would make more sense to let the mfd device handle > the base clocks. > In other words - what about pushing enable of perigh_clk and sys_clk to > the mfd driver. I think this could be achieved, but how is better? To have individual drivers (in this care I would say, child drivers, like e.g. this lcd driver) taking decisions on their own for their resources (even if shared) or to have parents taking decisions for them? Just asking. > > This may have the nice side-effect that we avoid > that both the drm driver and the pwm driver enable/disable the periph_clk > as it is today. > > Another comment - fixed_clksrc is used to determine if sys_clk is enabled. > But that flag is about the clksource selection, and it is just a coincidence > that the same flag can be used here. Yes, agree on this, I took advantage of fixed_clksrc to also enable the sys_clk based on fixed_clksrc to avoid introducing another member in struct atmel_hlcdc_dc_desc. At this moment this is valid only for SAM9X60 and I was thinking that in case some other scenario will appear I will do the appropriate changes. > Why we cannot always enable sys_clk? Do we need to do this only > for sam9x60? Only SAM9X60 requires this explicitly at probe. > IF yes, then add a new falg. If no, then skip the flag. > > Sam > > >> >> Signed-off-by: Sandeep Sheriker Mallikarjun <sandeepsheriker.mallikarjun@microchip.com> >> [claudiu.beznea@microchip.com: add fixed_clksrc checks] >> Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com> >> --- >> drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c | 19 ++++++++++++++++++- >> 1 file changed, 18 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c >> index 0be13eceedba..8bf51f853721 100644 >> --- a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c >> +++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c >> @@ -625,10 +625,18 @@ static int atmel_hlcdc_dc_load(struct drm_device *dev) >> dc->hlcdc = dev_get_drvdata(dev->dev->parent); >> dev->dev_private = dc; >> >> + if (dc->desc->fixed_clksrc) { >> + ret = clk_prepare_enable(dc->hlcdc->sys_clk); >> + if (ret) { >> + dev_err(dev->dev, "failed to enable sys_clk\n"); >> + goto err_destroy_wq; >> + } >> + } >> + >> ret = clk_prepare_enable(dc->hlcdc->periph_clk); >> if (ret) { >> dev_err(dev->dev, "failed to enable periph_clk\n"); >> - goto err_destroy_wq; >> + goto err_sys_clk_disable; >> } >> >> pm_runtime_enable(dev->dev); >> @@ -664,6 +672,9 @@ static int atmel_hlcdc_dc_load(struct drm_device *dev) >> err_periph_clk_disable: >> pm_runtime_disable(dev->dev); >> clk_disable_unprepare(dc->hlcdc->periph_clk); >> +err_sys_clk_disable: >> + if (dc->desc->fixed_clksrc) >> + clk_disable_unprepare(dc->hlcdc->sys_clk); >> >> err_destroy_wq: >> destroy_workqueue(dc->wq); >> @@ -688,6 +699,8 @@ static void atmel_hlcdc_dc_unload(struct drm_device *dev) >> >> pm_runtime_disable(dev->dev); >> clk_disable_unprepare(dc->hlcdc->periph_clk); >> + if (dc->desc->fixed_clksrc) >> + clk_disable_unprepare(dc->hlcdc->sys_clk); >> destroy_workqueue(dc->wq); >> } >> >> @@ -805,6 +818,8 @@ static int atmel_hlcdc_dc_drm_suspend(struct device *dev) >> regmap_read(regmap, ATMEL_HLCDC_IMR, &dc->suspend.imr); >> regmap_write(regmap, ATMEL_HLCDC_IDR, dc->suspend.imr); >> clk_disable_unprepare(dc->hlcdc->periph_clk); >> + if (dc->desc->fixed_clksrc) >> + clk_disable_unprepare(dc->hlcdc->sys_clk); >> >> return 0; >> } >> @@ -814,6 +829,8 @@ static int atmel_hlcdc_dc_drm_resume(struct device *dev) >> struct drm_device *drm_dev = dev_get_drvdata(dev); >> struct atmel_hlcdc_dc *dc = drm_dev->dev_private; >> >> + if (dc->desc->fixed_clksrc) >> + clk_prepare_enable(dc->hlcdc->sys_clk); >> clk_prepare_enable(dc->hlcdc->periph_clk); >> regmap_write(dc->hlcdc->regmap, ATMEL_HLCDC_IER, dc->suspend.imr); >> >> -- >> 2.7.4 >> >> _______________________________________________ >> dri-devel mailing list >> dri-devel@lists.freedesktop.org >> https://lists.freedesktop.org/mailman/listinfo/dri-devel >
diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c index 0be13eceedba..8bf51f853721 100644 --- a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c +++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c @@ -625,10 +625,18 @@ static int atmel_hlcdc_dc_load(struct drm_device *dev) dc->hlcdc = dev_get_drvdata(dev->dev->parent); dev->dev_private = dc; + if (dc->desc->fixed_clksrc) { + ret = clk_prepare_enable(dc->hlcdc->sys_clk); + if (ret) { + dev_err(dev->dev, "failed to enable sys_clk\n"); + goto err_destroy_wq; + } + } + ret = clk_prepare_enable(dc->hlcdc->periph_clk); if (ret) { dev_err(dev->dev, "failed to enable periph_clk\n"); - goto err_destroy_wq; + goto err_sys_clk_disable; } pm_runtime_enable(dev->dev); @@ -664,6 +672,9 @@ static int atmel_hlcdc_dc_load(struct drm_device *dev) err_periph_clk_disable: pm_runtime_disable(dev->dev); clk_disable_unprepare(dc->hlcdc->periph_clk); +err_sys_clk_disable: + if (dc->desc->fixed_clksrc) + clk_disable_unprepare(dc->hlcdc->sys_clk); err_destroy_wq: destroy_workqueue(dc->wq); @@ -688,6 +699,8 @@ static void atmel_hlcdc_dc_unload(struct drm_device *dev) pm_runtime_disable(dev->dev); clk_disable_unprepare(dc->hlcdc->periph_clk); + if (dc->desc->fixed_clksrc) + clk_disable_unprepare(dc->hlcdc->sys_clk); destroy_workqueue(dc->wq); } @@ -805,6 +818,8 @@ static int atmel_hlcdc_dc_drm_suspend(struct device *dev) regmap_read(regmap, ATMEL_HLCDC_IMR, &dc->suspend.imr); regmap_write(regmap, ATMEL_HLCDC_IDR, dc->suspend.imr); clk_disable_unprepare(dc->hlcdc->periph_clk); + if (dc->desc->fixed_clksrc) + clk_disable_unprepare(dc->hlcdc->sys_clk); return 0; } @@ -814,6 +829,8 @@ static int atmel_hlcdc_dc_drm_resume(struct device *dev) struct drm_device *drm_dev = dev_get_drvdata(dev); struct atmel_hlcdc_dc *dc = drm_dev->dev_private; + if (dc->desc->fixed_clksrc) + clk_prepare_enable(dc->hlcdc->sys_clk); clk_prepare_enable(dc->hlcdc->periph_clk); regmap_write(dc->hlcdc->regmap, ATMEL_HLCDC_IER, dc->suspend.imr);