drm/tinydrm: Make fb_dirty into a lower level hook

mipi_dbi_enable_flush() wants to call the fb->dirty() hook from the
bowels of the .atomic_enable() hook. That prevents us from taking the
plane mutex in fb->dirty() unless we also plumb down the acquire
context.

Instead it seems simpler to split the fb->dirty() into a tinydrm
specific lower level hook that can be called from
mipi_dbi_enable_flush() and from a generic higher level
tinydrm_fb_dirty() helper. As we don't have a tinydrm specific
vfuncs table we'll just stick it into tinydrm_device directly
for now.

v2: Deal with the fb->dirty() in tinydrm_display_pipe_update() as well (Noralf)

Cc: "Noralf Trønnes" <noralf@tronnes.org>
Cc: David Lechner <david@lechnology.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180323153509.15287-1-ville.syrjala@linux.intel.com
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Tested-by: Noralf Trønnes <noralf@tronnes.org>

drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c

@@ -78,6 +78,36 @@ bool tinydrm_merge_clips(struct drm_clip_rect *dst,
 }
 EXPORT_SYMBOL(tinydrm_merge_clips);
 
+int tinydrm_fb_dirty(struct drm_framebuffer *fb,
+		     struct drm_file *file_priv,
+		     unsigned int flags, unsigned int color,
+		     struct drm_clip_rect *clips,
+		     unsigned int num_clips)
+{
+	struct tinydrm_device *tdev = fb->dev->dev_private;
+	struct drm_plane *plane = &tdev->pipe.plane;
+	int ret = 0;
+
+	drm_modeset_lock(&plane->mutex, NULL);
+
+	/* fbdev can flush even when we're not interested */
+	if (plane->state->fb == fb) {
+		mutex_lock(&tdev->dirty_lock);
+		ret = tdev->fb_dirty(fb, file_priv, flags,
+				     color, clips, num_clips);
+		mutex_unlock(&tdev->dirty_lock);
+	}
+
+	drm_modeset_unlock(&plane->mutex);
+
+	if (ret)
+		dev_err_once(fb->dev->dev,
+			     "Failed to update display %d\n", ret);
+
+	return ret;
+}
+EXPORT_SYMBOL(tinydrm_fb_dirty);
+
 /**
  * tinydrm_memcpy - Copy clip buffer
  * @dst: Destination buffer

drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c

@@ -125,9 +125,8 @@ void tinydrm_display_pipe_update(struct drm_simple_display_pipe *pipe,
 	struct drm_crtc *crtc = &tdev->pipe.crtc;
 
 	if (fb && (fb != old_state->fb)) {
-		pipe->plane.fb = fb;
-		if (fb->funcs->dirty)
-			fb->funcs->dirty(fb, NULL, 0, 0, NULL, 0);
+		if (tdev->fb_dirty)
+			tdev->fb_dirty(fb, NULL, 0, 0, NULL, 0);
 	}
 
 	if (crtc->state->event) {

drivers/gpu/drm/tinydrm/ili9225.c

@@ -88,14 +88,8 @@ static int ili9225_fb_dirty(struct drm_framebuffer *fb,
 	bool full;
 	void *tr;
 
-	mutex_lock(&tdev->dirty_lock);
-
 	if (!mipi->enabled)
-		goto out_unlock;
-
-	/* fbdev can flush even when we're not interested */
-	if (tdev->pipe.plane.fb != fb)
-		goto out_unlock;
+		return 0;
 
 	full = tinydrm_merge_clips(&clip, clips, num_clips, flags,
 				   fb->width, fb->height);
@@ -108,7 +102,7 @@ static int ili9225_fb_dirty(struct drm_framebuffer *fb,
 		tr = mipi->tx_buf;
 		ret = mipi_dbi_buf_copy(mipi->tx_buf, fb, &clip, swap);
 		if (ret)
-			goto out_unlock;
+			return ret;
 	} else {
 		tr = cma_obj->vaddr;
 	}
@@ -159,20 +153,13 @@ static int ili9225_fb_dirty(struct drm_framebuffer *fb,
 	ret = mipi_dbi_command_buf(mipi, ILI9225_WRITE_DATA_TO_GRAM, tr,
 				(clip.x2 - clip.x1) * (clip.y2 - clip.y1) * 2);
 
-out_unlock:
-	mutex_unlock(&tdev->dirty_lock);
-
-	if (ret)
-		dev_err_once(fb->dev->dev, "Failed to update display %d\n",
-			     ret);
-
 	return ret;
 }
 
 static const struct drm_framebuffer_funcs ili9225_fb_funcs = {
 	.destroy	= drm_gem_fb_destroy,
 	.create_handle	= drm_gem_fb_create_handle,
-	.dirty		= ili9225_fb_dirty,
+	.dirty		= tinydrm_fb_dirty,
 };
 
 static void ili9225_pipe_enable(struct drm_simple_display_pipe *pipe,
@@ -269,7 +256,7 @@ static void ili9225_pipe_enable(struct drm_simple_display_pipe *pipe,
 
 	ili9225_command(mipi, ILI9225_DISPLAY_CONTROL_1, 0x1017);
 
-	mipi_dbi_enable_flush(mipi);
+	mipi_dbi_enable_flush(mipi, crtc_state, plane_state);
 }
 
 static void ili9225_pipe_disable(struct drm_simple_display_pipe *pipe)
@@ -342,6 +329,8 @@ static int ili9225_init(struct device *dev, struct mipi_dbi *mipi,
 	if (ret)
 		return ret;
 
+	tdev->fb_dirty = ili9225_fb_dirty;
+
 	ret = tinydrm_display_pipe_init(tdev, pipe_funcs,
 					DRM_MODE_CONNECTOR_VIRTUAL,
 					ili9225_formats,

drivers/gpu/drm/tinydrm/mi0283qt.c

@@ -127,7 +127,7 @@ static void mi0283qt_enable(struct drm_simple_display_pipe *pipe,
 	msleep(100);
 
 out_enable:
-	mipi_dbi_enable_flush(mipi);
+	mipi_dbi_enable_flush(mipi, crtc_state, plane_state);
 }
 
 static const struct drm_simple_display_pipe_funcs mi0283qt_pipe_funcs = {

drivers/gpu/drm/tinydrm/mipi-dbi.c

@@ -219,14 +219,8 @@ static int mipi_dbi_fb_dirty(struct drm_framebuffer *fb,
 	bool full;
 	void *tr;
 
-	mutex_lock(&tdev->dirty_lock);
-
 	if (!mipi->enabled)
-		goto out_unlock;
-
-	/* fbdev can flush even when we're not interested */
-	if (tdev->pipe.plane.fb != fb)
-		goto out_unlock;
+		return 0;
 
 	full = tinydrm_merge_clips(&clip, clips, num_clips, flags,
 				   fb->width, fb->height);
@@ -239,7 +233,7 @@ static int mipi_dbi_fb_dirty(struct drm_framebuffer *fb,
 		tr = mipi->tx_buf;
 		ret = mipi_dbi_buf_copy(mipi->tx_buf, fb, &clip, swap);
 		if (ret)
-			goto out_unlock;
+			return ret;
 	} else {
 		tr = cma_obj->vaddr;
 	}
@@ -254,20 +248,13 @@ static int mipi_dbi_fb_dirty(struct drm_framebuffer *fb,
 	ret = mipi_dbi_command_buf(mipi, MIPI_DCS_WRITE_MEMORY_START, tr,
 				(clip.x2 - clip.x1) * (clip.y2 - clip.y1) * 2);
 
-out_unlock:
-	mutex_unlock(&tdev->dirty_lock);
-
-	if (ret)
-		dev_err_once(fb->dev->dev, "Failed to update display %d\n",
-			     ret);
-
 	return ret;
 }
 
 static const struct drm_framebuffer_funcs mipi_dbi_fb_funcs = {
 	.destroy	= drm_gem_fb_destroy,
 	.create_handle	= drm_gem_fb_create_handle,
-	.dirty		= mipi_dbi_fb_dirty,
+	.dirty		= tinydrm_fb_dirty,
 };
 
 /**
@@ -278,13 +265,16 @@ static const struct drm_framebuffer_funcs mipi_dbi_fb_funcs = {
  * enables the backlight. Drivers can use this in their
  * &drm_simple_display_pipe_funcs->enable callback.
  */
-void mipi_dbi_enable_flush(struct mipi_dbi *mipi)
+void mipi_dbi_enable_flush(struct mipi_dbi *mipi,
+			   struct drm_crtc_state *crtc_state,
+			   struct drm_plane_state *plane_state)
 {
-	struct drm_framebuffer *fb = mipi->tinydrm.pipe.plane.fb;
+	struct tinydrm_device *tdev = &mipi->tinydrm;
+	struct drm_framebuffer *fb = plane_state->fb;
 
 	mipi->enabled = true;
 	if (fb)
-		fb->funcs->dirty(fb, NULL, 0, 0, NULL, 0);
+		tdev->fb_dirty(fb, NULL, 0, 0, NULL, 0);
 
 	backlight_enable(mipi->backlight);
 }
@@ -381,6 +371,8 @@ int mipi_dbi_init(struct device *dev, struct mipi_dbi *mipi,
 	if (ret)
 		return ret;
 
+	tdev->fb_dirty = mipi_dbi_fb_dirty;
+
 	/* TODO: Maybe add DRM_MODE_CONNECTOR_SPI */
 	ret = tinydrm_display_pipe_init(tdev, pipe_funcs,
 					DRM_MODE_CONNECTOR_VIRTUAL,

drivers/gpu/drm/tinydrm/repaper.c

@@ -540,14 +540,8 @@ static int repaper_fb_dirty(struct drm_framebuffer *fb,
 	clip.y1 = 0;
 	clip.y2 = fb->height;
 
-	mutex_lock(&tdev->dirty_lock);
-
 	if (!epd->enabled)
-		goto out_unlock;
-
-	/* fbdev can flush even when we're not interested */
-	if (tdev->pipe.plane.fb != fb)
-		goto out_unlock;
+		return 0;
 
 	repaper_get_temperature(epd);
 
@@ -555,16 +549,14 @@ static int repaper_fb_dirty(struct drm_framebuffer *fb,
 		  epd->factored_stage_time);
 
 	buf = kmalloc(fb->width * fb->height, GFP_KERNEL);
-	if (!buf) {
-		ret = -ENOMEM;
-		goto out_unlock;
-	}
+	if (!buf)
+		return -ENOMEM;
 
 	if (import_attach) {
 		ret = dma_buf_begin_cpu_access(import_attach->dmabuf,
 					       DMA_FROM_DEVICE);
 		if (ret)
-			goto out_unlock;
+			goto out_free;
 	}
 
 	tinydrm_xrgb8888_to_gray8(buf, cma_obj->vaddr, fb, &clip);
@@ -573,7 +565,7 @@ static int repaper_fb_dirty(struct drm_framebuffer *fb,
 		ret = dma_buf_end_cpu_access(import_attach->dmabuf,
 					     DMA_FROM_DEVICE);
 		if (ret)
-			goto out_unlock;
+			goto out_free;
 	}
 
 	repaper_gray8_to_mono_reversed(buf, fb->width, fb->height);
@@ -625,11 +617,7 @@ static int repaper_fb_dirty(struct drm_framebuffer *fb,
 			}
 	}
 
-out_unlock:
-	mutex_unlock(&tdev->dirty_lock);
-
-	if (ret)
-		DRM_DEV_ERROR(fb->dev->dev, "Failed to update display (%d)\n", ret);
+out_free:
 	kfree(buf);
 
 	return ret;
@@ -638,7 +626,7 @@ out_unlock:
 static const struct drm_framebuffer_funcs repaper_fb_funcs = {
 	.destroy	= drm_gem_fb_destroy,
 	.create_handle	= drm_gem_fb_create_handle,
-	.dirty		= repaper_fb_dirty,
+	.dirty		= tinydrm_fb_dirty,
 };
 
 static void power_off(struct repaper_epd *epd)
@@ -1070,6 +1058,8 @@ static int repaper_probe(struct spi_device *spi)
 	if (ret)
 		return ret;
 
+	tdev->fb_dirty = repaper_fb_dirty;
+
 	ret = tinydrm_display_pipe_init(tdev, &repaper_pipe_funcs,
 					DRM_MODE_CONNECTOR_VIRTUAL,
 					repaper_formats,

drivers/gpu/drm/tinydrm/st7586.c

@@ -120,14 +120,8 @@ static int st7586_fb_dirty(struct drm_framebuffer *fb,
 	int start, end;
 	int ret = 0;
 
-	mutex_lock(&tdev->dirty_lock);
-
 	if (!mipi->enabled)
-		goto out_unlock;
-
-	/* fbdev can flush even when we're not interested */
-	if (tdev->pipe.plane.fb != fb)
-		goto out_unlock;
+		return 0;
 
 	tinydrm_merge_clips(&clip, clips, num_clips, flags, fb->width,
 			    fb->height);
@@ -141,7 +135,7 @@ static int st7586_fb_dirty(struct drm_framebuffer *fb,
 
 	ret = st7586_buf_copy(mipi->tx_buf, fb, &clip);
 	if (ret)
-		goto out_unlock;
+		return ret;
 
 	/* Pixels are packed 3 per byte */
 	start = clip.x1 / 3;
@@ -158,20 +152,13 @@ static int st7586_fb_dirty(struct drm_framebuffer *fb,
 				   (u8 *)mipi->tx_buf,
 				   (end - start) * (clip.y2 - clip.y1));
 
-out_unlock:
-	mutex_unlock(&tdev->dirty_lock);
-
-	if (ret)
-		dev_err_once(fb->dev->dev, "Failed to update display %d\n",
-			     ret);
-
 	return ret;
 }
 
 static const struct drm_framebuffer_funcs st7586_fb_funcs = {
 	.destroy	= drm_gem_fb_destroy,
 	.create_handle	= drm_gem_fb_create_handle,
-	.dirty		= st7586_fb_dirty,
+	.dirty		= tinydrm_fb_dirty,
 };
 
 static void st7586_pipe_enable(struct drm_simple_display_pipe *pipe,
@@ -238,7 +225,7 @@ static void st7586_pipe_enable(struct drm_simple_display_pipe *pipe,
 
 	mipi_dbi_command(mipi, MIPI_DCS_SET_DISPLAY_ON);
 
-	mipi_dbi_enable_flush(mipi);
+	mipi_dbi_enable_flush(mipi, crtc_state, plane_state);
 }
 
 static void st7586_pipe_disable(struct drm_simple_display_pipe *pipe)
@@ -278,6 +265,8 @@ static int st7586_init(struct device *dev, struct mipi_dbi *mipi,
 	if (ret)
 		return ret;
 
+	tdev->fb_dirty = st7586_fb_dirty;
+
 	ret = tinydrm_display_pipe_init(tdev, pipe_funcs,
 					DRM_MODE_CONNECTOR_VIRTUAL,
 					st7586_formats,

drivers/gpu/drm/tinydrm/st7735r.c

@@ -99,7 +99,7 @@ static void jd_t18003_t01_pipe_enable(struct drm_simple_display_pipe *pipe,
 
 	msleep(20);
 
-	mipi_dbi_enable_flush(mipi);
+	mipi_dbi_enable_flush(mipi, crtc_state, plane_state);
 }
 
 static const struct drm_simple_display_pipe_funcs jd_t18003_t01_pipe_funcs = {

include/drm/tinydrm/mipi-dbi.h

@@ -67,7 +67,9 @@ int mipi_dbi_init(struct device *dev, struct mipi_dbi *mipi,
 		  const struct drm_simple_display_pipe_funcs *pipe_funcs,
 		  struct drm_driver *driver,
 		  const struct drm_display_mode *mode, unsigned int rotation);
-void mipi_dbi_enable_flush(struct mipi_dbi *mipi);
+void mipi_dbi_enable_flush(struct mipi_dbi *mipi,
+			   struct drm_crtc_state *crtc_state,
+			   struct drm_plane_state *plan_state);
 void mipi_dbi_pipe_disable(struct drm_simple_display_pipe *pipe);
 void mipi_dbi_hw_reset(struct mipi_dbi *mipi);
 bool mipi_dbi_display_is_on(struct mipi_dbi *mipi);

include/drm/tinydrm/tinydrm-helpers.h

@@ -36,6 +36,11 @@ static inline bool tinydrm_machine_little_endian(void)
 bool tinydrm_merge_clips(struct drm_clip_rect *dst,
 			 struct drm_clip_rect *src, unsigned int num_clips,
 			 unsigned int flags, u32 max_width, u32 max_height);
+int tinydrm_fb_dirty(struct drm_framebuffer *fb,
+		     struct drm_file *file_priv,
+		     unsigned int flags, unsigned int color,
+		     struct drm_clip_rect *clips,
+		     unsigned int num_clips);
 void tinydrm_memcpy(void *dst, void *vaddr, struct drm_framebuffer *fb,
 		    struct drm_clip_rect *clip);
 void tinydrm_swab16(u16 *dst, void *vaddr, struct drm_framebuffer *fb,

include/drm/tinydrm/tinydrm.h

@@ -26,6 +26,10 @@ struct tinydrm_device {
 	struct drm_simple_display_pipe pipe;
 	struct mutex dirty_lock;
 	const struct drm_framebuffer_funcs *fb_funcs;
+	int (*fb_dirty)(struct drm_framebuffer *framebuffer,
+			struct drm_file *file_priv, unsigned flags,
+			unsigned color, struct drm_clip_rect *clips,
+			unsigned num_clips);
 };
 
 static inline struct tinydrm_device *