From a95acec16d932ac78c2f70dc95a83bd162595d6c Mon Sep 17 00:00:00 2001 From: Liviu Dudau Date: Tue, 17 May 2016 10:06:54 +0100 Subject: [PATCH] drm: hdlcd: Revamp runtime power management Because the HDLCD driver acts as a component master it can end up enabling the runtime PM functionality before the encoders are initialised. This can cause crashes if the component slave never probes (missing module) or if the PM operations kick in before the probe finishes. Move the enabling of the runtime PM after the component master has finished collecting the slave components and use the DRM atomic helpers to suspend and resume the device. Tested-by: Robin Murphy Signed-off-by: Liviu Dudau --- drivers/gpu/drm/arm/hdlcd_crtc.c | 23 ++++++++------- drivers/gpu/drm/arm/hdlcd_drv.c | 48 ++++++++++++++++++-------------- drivers/gpu/drm/arm/hdlcd_drv.h | 3 +- 3 files changed, 39 insertions(+), 35 deletions(-) diff --git a/drivers/gpu/drm/arm/hdlcd_crtc.c b/drivers/gpu/drm/arm/hdlcd_crtc.c index fef1b04c2aab..d1e8d31e37ee 100644 --- a/drivers/gpu/drm/arm/hdlcd_crtc.c +++ b/drivers/gpu/drm/arm/hdlcd_crtc.c @@ -33,8 +33,17 @@ * */ +static void hdlcd_crtc_cleanup(struct drm_crtc *crtc) +{ + struct hdlcd_drm_private *hdlcd = crtc_to_hdlcd_priv(crtc); + + /* stop the controller on cleanup */ + hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 0); + drm_crtc_cleanup(crtc); +} + static const struct drm_crtc_funcs hdlcd_crtc_funcs = { - .destroy = drm_crtc_cleanup, + .destroy = hdlcd_crtc_cleanup, .set_config = drm_atomic_helper_set_config, .page_flip = drm_atomic_helper_page_flip, .reset = drm_atomic_helper_crtc_reset, @@ -155,8 +164,8 @@ static void hdlcd_crtc_disable(struct drm_crtc *crtc) if (!crtc->primary->fb) return; - clk_disable_unprepare(hdlcd->clk); hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 0); + clk_disable_unprepare(hdlcd->clk); drm_crtc_vblank_off(crtc); } @@ -294,16 +303,6 @@ static struct drm_plane *hdlcd_plane_init(struct drm_device *drm) return plane; } -void hdlcd_crtc_suspend(struct drm_crtc *crtc) -{ - hdlcd_crtc_disable(crtc); -} - -void hdlcd_crtc_resume(struct drm_crtc *crtc) -{ - hdlcd_crtc_enable(crtc); -} - int hdlcd_setup_crtc(struct drm_device *drm) { struct hdlcd_drm_private *hdlcd = drm->dev_private; diff --git a/drivers/gpu/drm/arm/hdlcd_drv.c b/drivers/gpu/drm/arm/hdlcd_drv.c index b987c63ba8d6..21b1427fc918 100644 --- a/drivers/gpu/drm/arm/hdlcd_drv.c +++ b/drivers/gpu/drm/arm/hdlcd_drv.c @@ -84,11 +84,7 @@ static int hdlcd_load(struct drm_device *drm, unsigned long flags) goto setup_fail; } - pm_runtime_enable(drm->dev); - - pm_runtime_get_sync(drm->dev); ret = drm_irq_install(drm, platform_get_irq(pdev, 0)); - pm_runtime_put_sync(drm->dev); if (ret < 0) { DRM_ERROR("failed to install IRQ handler\n"); goto irq_fail; @@ -357,6 +353,8 @@ static int hdlcd_drm_bind(struct device *dev) return -ENOMEM; drm->dev_private = hdlcd; + dev_set_drvdata(dev, drm); + hdlcd_setup_mode_config(drm); ret = hdlcd_load(drm, 0); if (ret) @@ -366,14 +364,18 @@ static int hdlcd_drm_bind(struct device *dev) if (ret) goto err_unload; - dev_set_drvdata(dev, drm); - ret = component_bind_all(dev, drm); if (ret) { DRM_ERROR("Failed to bind all components\n"); goto err_unregister; } + ret = pm_runtime_set_active(dev); + if (ret) + goto err_pm_active; + + pm_runtime_enable(dev); + ret = drm_vblank_init(drm, drm->mode_config.num_crtc); if (ret < 0) { DRM_ERROR("failed to initialise vblank\n"); @@ -399,16 +401,16 @@ err_fbdev: drm_mode_config_cleanup(drm); drm_vblank_cleanup(drm); err_vblank: + pm_runtime_disable(drm->dev); +err_pm_active: component_unbind_all(dev, drm); err_unregister: drm_dev_unregister(drm); err_unload: - pm_runtime_get_sync(drm->dev); drm_irq_uninstall(drm); - pm_runtime_put_sync(drm->dev); - pm_runtime_disable(drm->dev); of_reserved_mem_device_release(drm->dev); err_free: + dev_set_drvdata(dev, NULL); drm_dev_unref(drm); return ret; @@ -495,30 +497,34 @@ MODULE_DEVICE_TABLE(of, hdlcd_of_match); static int __maybe_unused hdlcd_pm_suspend(struct device *dev) { struct drm_device *drm = dev_get_drvdata(dev); - struct drm_crtc *crtc; + struct hdlcd_drm_private *hdlcd = drm ? drm->dev_private : NULL; - if (pm_runtime_suspended(dev)) + if (!hdlcd) return 0; - drm_modeset_lock_all(drm); - list_for_each_entry(crtc, &drm->mode_config.crtc_list, head) - hdlcd_crtc_suspend(crtc); - drm_modeset_unlock_all(drm); + drm_kms_helper_poll_disable(drm); + + hdlcd->state = drm_atomic_helper_suspend(drm); + if (IS_ERR(hdlcd->state)) { + drm_kms_helper_poll_enable(drm); + return PTR_ERR(hdlcd->state); + } + return 0; } static int __maybe_unused hdlcd_pm_resume(struct device *dev) { struct drm_device *drm = dev_get_drvdata(dev); - struct drm_crtc *crtc; + struct hdlcd_drm_private *hdlcd = drm ? drm->dev_private : NULL; - if (!pm_runtime_suspended(dev)) + if (!hdlcd) return 0; - drm_modeset_lock_all(drm); - list_for_each_entry(crtc, &drm->mode_config.crtc_list, head) - hdlcd_crtc_resume(crtc); - drm_modeset_unlock_all(drm); + drm_atomic_helper_resume(drm, hdlcd->state); + drm_kms_helper_poll_enable(drm); + pm_runtime_set_active(dev); + return 0; } diff --git a/drivers/gpu/drm/arm/hdlcd_drv.h b/drivers/gpu/drm/arm/hdlcd_drv.h index aa234784f053..e7cea8233958 100644 --- a/drivers/gpu/drm/arm/hdlcd_drv.h +++ b/drivers/gpu/drm/arm/hdlcd_drv.h @@ -13,6 +13,7 @@ struct hdlcd_drm_private { struct list_head event_list; struct drm_crtc crtc; struct drm_plane *plane; + struct drm_atomic_state *state; #ifdef CONFIG_DEBUG_FS atomic_t buffer_underrun_count; atomic_t bus_error_count; @@ -36,7 +37,5 @@ static inline u32 hdlcd_read(struct hdlcd_drm_private *hdlcd, unsigned int reg) int hdlcd_setup_crtc(struct drm_device *dev); void hdlcd_set_scanout(struct hdlcd_drm_private *hdlcd); -void hdlcd_crtc_suspend(struct drm_crtc *crtc); -void hdlcd_crtc_resume(struct drm_crtc *crtc); #endif /* __HDLCD_DRV_H__ */ -- 2.20.1