[PATCH 3/6] drm/fb-cma-helper: Support device unplug
Noralf Trønnes
noralf at tronnes.org
Mon Aug 28 17:17:45 UTC 2017
Add drm_fbdev_cma_dev_unplug() and use the drm_fb_helper device unplug
support. Pin driver module on fb_open().
Cc: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
Signed-off-by: Noralf Trønnes <noralf at tronnes.org>
---
drivers/gpu/drm/drm_fb_cma_helper.c | 139 +++++++++++++++++-------------------
include/drm/drm_fb_cma_helper.h | 1 +
2 files changed, 68 insertions(+), 72 deletions(-)
diff --git a/drivers/gpu/drm/drm_fb_cma_helper.c b/drivers/gpu/drm/drm_fb_cma_helper.c
index f2ee883..2b044be 100644
--- a/drivers/gpu/drm/drm_fb_cma_helper.c
+++ b/drivers/gpu/drm/drm_fb_cma_helper.c
@@ -25,8 +25,6 @@
#include <drm/drm_fb_cma_helper.h>
#include <linux/module.h>
-#define DEFAULT_FBDEFIO_DELAY_MS 50
-
struct drm_fbdev_cma {
struct drm_fb_helper fb_helper;
const struct drm_framebuffer_funcs *fb_funcs;
@@ -238,6 +236,34 @@ int drm_fb_cma_debugfs_show(struct seq_file *m, void *arg)
EXPORT_SYMBOL_GPL(drm_fb_cma_debugfs_show);
#endif
+static int drm_fbdev_cma_fb_open(struct fb_info *info, int user)
+{
+ struct drm_fb_helper *fb_helper = info->par;
+ struct drm_device *dev = fb_helper->dev;
+
+ /*
+ * The fb_ops definition resides in this library, meaning fb_open()
+ * will take a ref on the library instead of the driver. Make sure the
+ * driver module is pinned. Skip fbcon (user==0) since it can detach
+ * itself on unregister_framebuffer().
+ */
+ if (user && !try_module_get(dev->driver->fops->owner))
+ return -ENODEV;
+
+ return 0;
+}
+
+static int drm_fbdev_cma_fb_release(struct fb_info *info, int user)
+{
+ struct drm_fb_helper *fb_helper = info->par;
+ struct drm_device *dev = fb_helper->dev;
+
+ if (user)
+ module_put(dev->driver->fops->owner);
+
+ return 0;
+}
+
static int drm_fb_cma_mmap(struct fb_info *info, struct vm_area_struct *vma)
{
return dma_mmap_writecombine(info->device, vma, info->screen_base,
@@ -247,10 +273,13 @@ static int drm_fb_cma_mmap(struct fb_info *info, struct vm_area_struct *vma)
static struct fb_ops drm_fbdev_cma_ops = {
.owner = THIS_MODULE,
DRM_FB_HELPER_DEFAULT_OPS,
+ .fb_open = drm_fbdev_cma_fb_open,
+ .fb_release = drm_fbdev_cma_fb_release,
.fb_fillrect = drm_fb_helper_sys_fillrect,
.fb_copyarea = drm_fb_helper_sys_copyarea,
.fb_imageblit = drm_fb_helper_sys_imageblit,
.fb_mmap = drm_fb_cma_mmap,
+ .fb_destroy = drm_fb_helper_fb_destroy,
};
static int drm_fbdev_cma_deferred_io_mmap(struct fb_info *info,
@@ -262,52 +291,26 @@ static int drm_fbdev_cma_deferred_io_mmap(struct fb_info *info,
return 0;
}
-static int drm_fbdev_cma_defio_init(struct fb_info *fbi,
+static int drm_fbdev_cma_defio_init(struct drm_fb_helper *helper,
struct drm_gem_cma_object *cma_obj)
{
- struct fb_deferred_io *fbdefio;
- struct fb_ops *fbops;
+ struct fb_info *fbi = helper->fbdev;
+ int ret;
- /*
- * Per device structures are needed because:
- * fbops: fb_deferred_io_cleanup() clears fbops.fb_mmap
- * fbdefio: individual delays
- */
- fbdefio = kzalloc(sizeof(*fbdefio), GFP_KERNEL);
- fbops = kzalloc(sizeof(*fbops), GFP_KERNEL);
- if (!fbdefio || !fbops) {
- kfree(fbdefio);
- kfree(fbops);
- return -ENOMEM;
- }
+ ret = drm_fb_helper_defio_init(helper);
+ if (ret)
+ return ret;
/* can't be offset from vaddr since dirty() uses cma_obj */
fbi->screen_buffer = cma_obj->vaddr;
/* fb_deferred_io_fault() needs a physical address */
fbi->fix.smem_start = page_to_phys(virt_to_page(fbi->screen_buffer));
- *fbops = *fbi->fbops;
- fbi->fbops = fbops;
-
- fbdefio->delay = msecs_to_jiffies(DEFAULT_FBDEFIO_DELAY_MS);
- fbdefio->deferred_io = drm_fb_helper_deferred_io;
- fbi->fbdefio = fbdefio;
- fb_deferred_io_init(fbi);
fbi->fbops->fb_mmap = drm_fbdev_cma_deferred_io_mmap;
return 0;
}
-static void drm_fbdev_cma_defio_fini(struct fb_info *fbi)
-{
- if (!fbi->fbdefio)
- return;
-
- fb_deferred_io_cleanup(fbi);
- kfree(fbi->fbdefio);
- kfree(fbi->fbops);
-}
-
static int
drm_fbdev_cma_create(struct drm_fb_helper *helper,
struct drm_fb_helper_surface_size *sizes)
@@ -365,7 +368,7 @@ drm_fbdev_cma_create(struct drm_fb_helper *helper,
fbi->fix.smem_len = size;
if (fbdev_cma->fb_funcs->dirty) {
- ret = drm_fbdev_cma_defio_init(fbi, obj);
+ ret = drm_fbdev_cma_defio_init(helper, obj);
if (ret)
goto err_cma_destroy;
}
@@ -399,7 +402,6 @@ struct drm_fbdev_cma *drm_fbdev_cma_init_with_funcs(struct drm_device *dev,
const struct drm_framebuffer_funcs *funcs)
{
struct drm_fbdev_cma *fbdev_cma;
- struct drm_fb_helper *helper;
int ret;
fbdev_cma = kzalloc(sizeof(*fbdev_cma), GFP_KERNEL);
@@ -409,37 +411,15 @@ struct drm_fbdev_cma *drm_fbdev_cma_init_with_funcs(struct drm_device *dev,
}
fbdev_cma->fb_funcs = funcs;
- helper = &fbdev_cma->fb_helper;
-
- drm_fb_helper_prepare(dev, helper, &drm_fb_cma_helper_funcs);
-
- ret = drm_fb_helper_init(dev, helper, max_conn_count);
- if (ret < 0) {
- dev_err(dev->dev, "Failed to initialize drm fb helper.\n");
- goto err_free;
- }
-
- ret = drm_fb_helper_single_add_all_connectors(helper);
- if (ret < 0) {
- dev_err(dev->dev, "Failed to add connectors.\n");
- goto err_drm_fb_helper_fini;
-
- }
-
- ret = drm_fb_helper_initial_config(helper, preferred_bpp);
- if (ret < 0) {
- dev_err(dev->dev, "Failed to set initial hw configuration.\n");
- goto err_drm_fb_helper_fini;
+ ret = drm_fb_helper_simple_init(dev, &fbdev_cma->fb_helper,
+ preferred_bpp, max_conn_count,
+ &drm_fb_cma_helper_funcs);
+ if (ret) {
+ kfree(fbdev_cma);
+ return ERR_PTR(ret);
}
return fbdev_cma;
-
-err_drm_fb_helper_fini:
- drm_fb_helper_fini(helper);
-err_free:
- kfree(fbdev_cma);
-
- return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(drm_fbdev_cma_init_with_funcs);
@@ -468,17 +448,15 @@ EXPORT_SYMBOL_GPL(drm_fbdev_cma_init);
/**
* drm_fbdev_cma_fini() - Free drm_fbdev_cma struct
* @fbdev_cma: The drm_fbdev_cma struct
+ *
+ * This function calls drm_fb_helper_simple_fini() and frees @fbdev_cma.
+ *
+ * Don't use this function together with drm_fbdev_cma_dev_unplug().
*/
void drm_fbdev_cma_fini(struct drm_fbdev_cma *fbdev_cma)
{
- drm_fb_helper_unregister_fbi(&fbdev_cma->fb_helper);
- if (fbdev_cma->fb_helper.fbdev)
- drm_fbdev_cma_defio_fini(fbdev_cma->fb_helper.fbdev);
-
- if (fbdev_cma->fb_helper.fb)
- drm_framebuffer_remove(fbdev_cma->fb_helper.fb);
-
- drm_fb_helper_fini(&fbdev_cma->fb_helper);
+ if (fbdev_cma)
+ drm_fb_helper_simple_fini(&fbdev_cma->fb_helper);
kfree(fbdev_cma);
}
EXPORT_SYMBOL_GPL(drm_fbdev_cma_fini);
@@ -542,3 +520,20 @@ void drm_fbdev_cma_set_suspend_unlocked(struct drm_fbdev_cma *fbdev_cma,
state);
}
EXPORT_SYMBOL(drm_fbdev_cma_set_suspend_unlocked);
+
+/**
+ * drm_fbdev_cma_dev_unplug - wrapper around drm_fb_helper_dev_unplug
+ * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
+ *
+ * This unplugs the fbdev emulation for a hotpluggable DRM device. See
+ * drm_fb_helper_dev_unplug() for details.
+ *
+ * Drivers must call drm_mode_config_cleanup() and free @fbdev_cma in their
+ * &drm_driver->release callback.
+ */
+void drm_fbdev_cma_dev_unplug(struct drm_fbdev_cma *fbdev_cma)
+{
+ if (fbdev_cma)
+ drm_fb_helper_dev_unplug(&fbdev_cma->fb_helper);
+}
+EXPORT_SYMBOL(drm_fbdev_cma_dev_unplug);
diff --git a/include/drm/drm_fb_cma_helper.h b/include/drm/drm_fb_cma_helper.h
index a323781..a6aafae 100644
--- a/include/drm/drm_fb_cma_helper.h
+++ b/include/drm/drm_fb_cma_helper.h
@@ -27,6 +27,7 @@ void drm_fbdev_cma_hotplug_event(struct drm_fbdev_cma *fbdev_cma);
void drm_fbdev_cma_set_suspend(struct drm_fbdev_cma *fbdev_cma, bool state);
void drm_fbdev_cma_set_suspend_unlocked(struct drm_fbdev_cma *fbdev_cma,
bool state);
+void drm_fbdev_cma_dev_unplug(struct drm_fbdev_cma *fbdev_cma);
void drm_fb_cma_destroy(struct drm_framebuffer *fb);
int drm_fb_cma_create_handle(struct drm_framebuffer *fb,
--
2.7.4
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