From: Jeffy Chen <jeffy.chen@xxxxxxxxxxxxxx> Since we are trying to access components' resources in the master's suspend/resume PM callbacks(e.g. panel), add device links to correct the suspend/resume and shutdown ordering. Signed-off-by: Jeffy Chen <jeffy.chen at rock-chips.com> Signed-off-by: Enric Balletbo i Serra <enric.balletbo at collabora.com> --- Hi, This is an attempt to revive a patch [1] that was sent last October. Sean Paul requested some changes but I think that never was send a v5 version. The patch fixes and issue where backlight panel is not correctly recoved after a resume. This was tested on top of current linux-next plus the latest series of Thierry's patches [2] [1] https://patchwork.kernel.org/patch/10011595/ [2] https://lkml.org/lkml/2018/1/30/621 Changes in v5: Address the comments from Sean. - Create a helper to do the cleanup. - Call the helper in rockchip_drm_match_add and where needed. Changes in v4: None Changes in v3: None Changes in v2: Use device link to correct the suspend/resume and shutdown ordering, instead of converting rockchip spi's suspend/resume PM callbacks to late suspend/resume PM callbacks. Thanks, Enric drivers/gpu/drm/rockchip/rockchip_drm_drv.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c index 0609113d6a71..f814d37b1db2 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c @@ -314,6 +314,14 @@ static int compare_dev(struct device *dev, void *data) return dev == (struct device *)data; } +static void rockchip_drm_match_remove(struct device *dev) +{ + struct device_link *link; + + list_for_each_entry(link, &dev->links.consumers, s_node) + device_link_del(link); +} + static struct component_match *rockchip_drm_match_add(struct device *dev) { struct component_match *match = NULL; @@ -331,10 +339,15 @@ static struct component_match *rockchip_drm_match_add(struct device *dev) if (!d) break; + + device_link_add(dev, d, DL_FLAG_STATELESS); component_match_add(dev, &match, compare_dev, d); } while (true); } + if (IS_ERR(match)) + rockchip_drm_match_remove(dev); + return match ?: ERR_PTR(-ENODEV); } @@ -411,13 +424,21 @@ static int rockchip_drm_platform_probe(struct platform_device *pdev) if (IS_ERR(match)) return PTR_ERR(match); - return component_master_add_with_match(dev, &rockchip_drm_ops, match); + ret = component_master_add_with_match(dev, &rockchip_drm_ops, match); + if (ret < 0) { + rockchip_drm_match_remove(dev); + return ret; + } + + return 0; } static int rockchip_drm_platform_remove(struct platform_device *pdev) { component_master_del(&pdev->dev, &rockchip_drm_ops); + rockchip_drm_match_remove(&pdev->dev); + return 0; } -- 2.15.1