Hi Geert, Thank you for the patch.
On Thu, Jun 22, 2023 at 11:21:18AM +0200, Geert Uytterhoeven wrote: > The SH-Mobile LCD Controller is part of a PM Domain on all relevant SoCs > (clock domain on all, power domain on some). Hence it may not be > sufficient to manage the LCDC module clock explicitly (e.g. if the > selected clock source differs from SHMOB_DRM_CLK_BUS). > > Fix this by using Runtime PM instead. > > Signed-off-by: Geert Uytterhoeven <[email protected]> > --- > drivers/gpu/drm/renesas/shmobile/shmob_drm_crtc.c | 11 ++++++++++- > drivers/gpu/drm/renesas/shmobile/shmob_drm_drv.c | 5 +++++ > 2 files changed, 15 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/renesas/shmobile/shmob_drm_crtc.c > b/drivers/gpu/drm/renesas/shmobile/shmob_drm_crtc.c > index fbfd906844da490c..84dbf35025d7be63 100644 > --- a/drivers/gpu/drm/renesas/shmobile/shmob_drm_crtc.c > +++ b/drivers/gpu/drm/renesas/shmobile/shmob_drm_crtc.c > @@ -9,6 +9,7 @@ > > #include <linux/backlight.h> > #include <linux/clk.h> > +#include <linux/pm_runtime.h> > > #include <drm/drm_crtc.h> > #include <drm/drm_crtc_helper.h> > @@ -170,10 +171,16 @@ static void shmob_drm_crtc_start(struct shmob_drm_crtc > *scrtc) > if (WARN_ON(format == NULL)) > return; > > + ret = pm_runtime_resume_and_get(sdev->dev); > + if (ret) > + return; > + > /* Enable clocks before accessing the hardware. */ > ret = shmob_drm_clk_on(sdev); This would be best located in the runtime PM resume handler. Same for disabling clocks in the runtime PM suspend handler. > - if (ret < 0) > + if (ret < 0) { > + pm_runtime_put(sdev->dev); > return; > + } > > /* Reset and enable the LCDC. */ > lcdc_write(sdev, LDCNT2R, lcdc_read(sdev, LDCNT2R) | LDCNT2R_BR); > @@ -271,6 +278,8 @@ static void shmob_drm_crtc_stop(struct shmob_drm_crtc > *scrtc) > /* Stop clocks. */ > shmob_drm_clk_off(sdev); > > + pm_runtime_put(sdev->dev); > + > scrtc->started = false; > } > > diff --git a/drivers/gpu/drm/renesas/shmobile/shmob_drm_drv.c > b/drivers/gpu/drm/renesas/shmobile/shmob_drm_drv.c > index 30493ce874192e3e..4f01caa119637032 100644 > --- a/drivers/gpu/drm/renesas/shmobile/shmob_drm_drv.c > +++ b/drivers/gpu/drm/renesas/shmobile/shmob_drm_drv.c > @@ -13,6 +13,7 @@ > #include <linux/module.h> > #include <linux/platform_device.h> > #include <linux/pm.h> > +#include <linux/pm_runtime.h> > #include <linux/slab.h> > > #include <drm/drm_drv.h> > @@ -216,6 +217,10 @@ static int shmob_drm_probe(struct platform_device *pdev) > if (IS_ERR(sdev->mmio)) > return PTR_ERR(sdev->mmio); > > + ret = devm_pm_runtime_enable(&pdev->dev); > + if (ret) > + return ret; > + I would move this after shmob_drm_setup_clocks(), to ensure that the runtime PM suspend and resume handlers will have access to clocks. > ret = shmob_drm_setup_clocks(sdev, pdata->clk_source); > if (ret < 0) > return ret; -- Regards, Laurent Pinchart
