diff options
Diffstat (limited to 'drivers/gpu/drm/drm_fb_helper.c')
| -rw-r--r-- | drivers/gpu/drm/drm_fb_helper.c | 74 |
1 files changed, 68 insertions, 6 deletions
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index aed79d3..03414bd 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -29,6 +29,7 @@ */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include <linux/console.h> #include <linux/kernel.h> #include <linux/sysrq.h> #include <linux/slab.h> @@ -40,6 +41,8 @@ #include <drm/drm_atomic.h> #include <drm/drm_atomic_helper.h> +#include "drm_crtc_helper_internal.h" + static bool drm_fbdev_emulation = true; module_param_named(fbdev_emulation, drm_fbdev_emulation, bool, 0600); MODULE_PARM_DESC(fbdev_emulation, @@ -463,7 +466,7 @@ static bool drm_fb_helper_is_bound(struct drm_fb_helper *fb_helper) /* Sometimes user space wants everything disabled, so don't steal the * display if there's a master. */ - if (lockless_dereference(dev->master)) + if (READ_ONCE(dev->master)) return false; drm_for_each_crtc(crtc, dev) { @@ -617,6 +620,16 @@ static void drm_fb_helper_crtc_free(struct drm_fb_helper *helper) kfree(helper->crtc_info); } +static void drm_fb_helper_resume_worker(struct work_struct *work) +{ + struct drm_fb_helper *helper = container_of(work, struct drm_fb_helper, + resume_work); + + console_lock(); + fb_set_suspend(helper->fbdev, 0); + console_unlock(); +} + static void drm_fb_helper_dirty_work(struct work_struct *work) { struct drm_fb_helper *helper = container_of(work, struct drm_fb_helper, @@ -648,6 +661,7 @@ void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper, { INIT_LIST_HEAD(&helper->kernel_fb_list); spin_lock_init(&helper->dirty_lock); + INIT_WORK(&helper->resume_work, drm_fb_helper_resume_worker); INIT_WORK(&helper->dirty_work, drm_fb_helper_dirty_work); helper->dirty_clip.x1 = helper->dirty_clip.y1 = ~0; helper->funcs = funcs; @@ -1023,17 +1037,65 @@ EXPORT_SYMBOL(drm_fb_helper_cfb_imageblit); /** * drm_fb_helper_set_suspend - wrapper around fb_set_suspend * @fb_helper: driver-allocated fbdev helper - * @state: desired state, zero to resume, non-zero to suspend + * @suspend: whether to suspend or resume * - * A wrapper around fb_set_suspend implemented by fbdev core + * A wrapper around fb_set_suspend implemented by fbdev core. + * Use drm_fb_helper_set_suspend_unlocked() if you don't need to take + * the lock yourself */ -void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, int state) +void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, bool suspend) { if (fb_helper && fb_helper->fbdev) - fb_set_suspend(fb_helper->fbdev, state); + fb_set_suspend(fb_helper->fbdev, suspend); } EXPORT_SYMBOL(drm_fb_helper_set_suspend); +/** + * drm_fb_helper_set_suspend_unlocked - wrapper around fb_set_suspend that also + * takes the console lock + * @fb_helper: driver-allocated fbdev helper + * @suspend: whether to suspend or resume + * + * A wrapper around fb_set_suspend() that takes the console lock. If the lock + * isn't available on resume, a worker is tasked with waiting for the lock + * to become available. The console lock can be pretty contented on resume + * due to all the printk activity. + * + * This function can be called multiple times with the same state since + * &fb_info->state is checked to see if fbdev is running or not before locking. + * + * Use drm_fb_helper_set_suspend() if you need to take the lock yourself. + */ +void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper, + bool suspend) +{ + if (!fb_helper || !fb_helper->fbdev) + return; + + /* make sure there's no pending/ongoing resume */ + flush_work(&fb_helper->resume_work); + + if (suspend) { + if (fb_helper->fbdev->state != FBINFO_STATE_RUNNING) + return; + + console_lock(); + + } else { + if (fb_helper->fbdev->state == FBINFO_STATE_RUNNING) + return; + + if (!console_trylock()) { + schedule_work(&fb_helper->resume_work); + return; + } + } + + fb_set_suspend(fb_helper->fbdev, suspend); + console_unlock(); +} +EXPORT_SYMBOL(drm_fb_helper_set_suspend_unlocked); + static int setcolreg(struct drm_crtc *crtc, u16 red, u16 green, u16 blue, u16 regno, struct fb_info *info) { @@ -2193,7 +2255,7 @@ EXPORT_SYMBOL(drm_fb_helper_initial_config); * @fb_helper: the drm_fb_helper * * Scan the connectors attached to the fb_helper and try to put together a - * setup after *notification of a change in output configuration. + * setup after notification of a change in output configuration. * * Called at runtime, takes the mode config locks to be able to check/change the * modeset configuration. Must be run from process context (which usually means |
