Re: [PATCH v2 13/26] drm/fb_cma_helper: Remove implicit call to disable_unused_functions
From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Date: 2016-01-14 23:12:52
Also in:
dri-devel, linux-arm-kernel, linux-clk, lkml
Hi Maxime, Thank you for the patch. On Thursday 14 January 2016 16:24:56 Maxime Ripard wrote:
The drm_fbdev_cma_init function always calls the drm_helper_disable_unused_functions. Since it's part of the usual probe process, all the drivers using that helper will end up having their encoder and CRTC disable functions called at probe if their device has not been reported as enabled. This could be fixed by reading out from the registers the current state of the device if it is enabled, but even that will not handle the case where the device is actually disabled. Moreover, the drivers using the atomic modesetting expect that their enable and disable callback to be called when the device is already enabled or disabled (respectively). We can however fix this issue by moving the call to drm_helper_disable_unused_functions out of drm_fbdev_cma_init and make the drivers needing it (all the drivers calling drm_fbdev_cma_init and not using the atomic modesetting) explicitly call it.
I'd rather add it to all drivers that call drm_fbdev_cma_init(). All the atomic ones must have special code to cope with it that could be rendered useless by the removal of the drm_helper_disable_unused_functions() call. That code should be removed too, and it would be easier to check drivers one by one and fixing them individually (outside of this patch series, unless you insist ;-)) when removing the explicit drm_helper_disable_unused_functions() call. Other than that the patch looks fine to me.
quoted hunk ↗ jump to hunk
Signed-off-by: Maxime Ripard <redacted> --- drivers/gpu/drm/drm_fb_cma_helper.c | 3 --- drivers/gpu/drm/imx/imx-drm-core.c | 1 + drivers/gpu/drm/sti/sti_drv.c | 1 + drivers/gpu/drm/tilcdc/tilcdc_drv.c | 1 + 4 files changed, 3 insertions(+), 3 deletions(-)diff --git a/drivers/gpu/drm/drm_fb_cma_helper.cb/drivers/gpu/drm/drm_fb_cma_helper.c index c19a62561183..daa98d881142 100644--- a/drivers/gpu/drm/drm_fb_cma_helper.c +++ b/drivers/gpu/drm/drm_fb_cma_helper.c@@ -348,9 +348,6 @@ struct drm_fbdev_cma *drm_fbdev_cma_init(structdrm_device *dev, } - /* disable all the possible outputs/crtcs before entering KMS mode */ - drm_helper_disable_unused_functions(dev); - ret = drm_fb_helper_initial_config(helper, preferred_bpp); if (ret < 0) { dev_err(dev->dev, "Failed to set initial hw configuration.\n");diff --git a/drivers/gpu/drm/imx/imx-drm-core.cb/drivers/gpu/drm/imx/imx-drm-core.c index 7b990b4e96d2..e1db57791fc9 100644--- a/drivers/gpu/drm/imx/imx-drm-core.c +++ b/drivers/gpu/drm/imx/imx-drm-core.c@@ -312,6 +312,7 @@ static int imx_drm_driver_load(struct drm_device *drm,unsigned long flags) dev_warn(drm->dev, "Invalid legacyfb_depth. Defaulting to 16bpp\n"); legacyfb_depth = 16; } + drm_helper_disable_unused_functions(drm); imxdrm->fbhelper = drm_fbdev_cma_init(drm, legacyfb_depth, drm->mode_config.num_crtc, MAX_CRTC); if (IS_ERR(imxdrm->fbhelper)) {diff --git a/drivers/gpu/drm/sti/sti_drv.c b/drivers/gpu/drm/sti/sti_drv.c index 1469987949d8..506b5626f3ed 100644 --- a/drivers/gpu/drm/sti/sti_drv.c +++ b/drivers/gpu/drm/sti/sti_drv.c@@ -160,6 +160,7 @@ static int sti_load(struct drm_device *dev, unsignedlong flags) drm_mode_config_reset(dev); + drm_helper_disable_unused_functions(dev); drm_fbdev_cma_init(dev, 32, dev->mode_config.num_crtc, dev->mode_config.num_connector);diff --git a/drivers/gpu/drm/tilcdc/tilcdc_drv.cb/drivers/gpu/drm/tilcdc/tilcdc_drv.c index 876cad58b1f9..24be31d69701 100644--- a/drivers/gpu/drm/tilcdc/tilcdc_drv.c +++ b/drivers/gpu/drm/tilcdc/tilcdc_drv.c@@ -294,6 +294,7 @@ static int tilcdc_load(struct drm_device *dev, unsignedlong flags) break; } + drm_helper_disable_unused_functions(dev); priv->fbdev = drm_fbdev_cma_init(dev, bpp, dev->mode_config.num_crtc, dev->mode_config.num_connector);
-- Regards, Laurent Pinchart _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/dri-devel