Merge tag 'sunxi-drm-fixes-for-4.7' of https://git.kernel.org/pub/scm/linux/kernel/git/mripard/linux into drm-fixes

Allwinner sun4i DRM driver fixes

A bunch of fixes that address:
  - Compilation errors in various corner cases
  - Move to helpers
  - Fix the pixel clock computation
  - Fix our panel probe

* tag 'sunxi-drm-fixes-for-4.7' of https://git.kernel.org/pub/scm/linux/kernel/git/mripard/linux:
  drm: sun4i: do cleanup if RGB output init fails
  drm/sun4i: Convert to connector register helpers
  drm/sun4i: remove simplefb at probe
  drm/sun4i: rgb: panel is an error pointer
  drm/sun4i: defer only if we didn't find our panel
  drm/sun4i: rgb: Validate the clock rate
  drm/sun4i: request exact rates to our parents
  drm: sun4i: fix probe error handling
  drm: sun4i: print DMA address correctly
  drm/sun4i: add COMMON_CLK dependency

6 files changed, 88 insertions, 46 deletions

diff --git a/drivers/gpu/drm/sun4i/Kconfig b/drivers/gpu/drm/sun4i/Kconfig
index 99510e64e91a..a4b357db8856 100644
--- a/drivers/gpu/drm/sun4i/Kconfig
+++ b/drivers/gpu/drm/sun4i/Kconfig
@@ -1,6 +1,6 @@
 config DRM_SUN4I
 	tristate "DRM Support for Allwinner A10 Display Engine"
-	depends on DRM && ARM
+	depends on DRM && ARM && COMMON_CLK
 	depends on ARCH_SUNXI || COMPILE_TEST
 	select DRM_GEM_CMA_HELPER
 	select DRM_KMS_HELPER
diff --git a/drivers/gpu/drm/sun4i/sun4i_backend.c b/drivers/gpu/drm/sun4i/sun4i_backend.c
index f7a15c1a93bf..3ab560450a82 100644
--- a/drivers/gpu/drm/sun4i/sun4i_backend.c
+++ b/drivers/gpu/drm/sun4i/sun4i_backend.c
@@ -190,7 +190,7 @@ int sun4i_backend_update_layer_buffer(struct sun4i_backend *backend,
 	/* Get the physical address of the buffer in memory */
 	gem = drm_fb_cma_get_gem_obj(fb, 0);
 
-	DRM_DEBUG_DRIVER("Using GEM @ 0x%x\n", gem->paddr);
+	DRM_DEBUG_DRIVER("Using GEM @ %pad\n", &gem->paddr);
 
 	/* Compute the start of the displayed memory */
 	bpp = drm_format_plane_cpp(fb->pixel_format, 0);
@@ -198,7 +198,7 @@ int sun4i_backend_update_layer_buffer(struct sun4i_backend *backend,
 	paddr += (state->src_x >> 16) * bpp;
 	paddr += (state->src_y >> 16) * fb->pitches[0];
 
-	DRM_DEBUG_DRIVER("Setting buffer address to 0x%x\n", paddr);
+	DRM_DEBUG_DRIVER("Setting buffer address to %pad\n", &paddr);
 
 	/* Write the 32 lower bits of the address (in bits) */
 	lo_paddr = paddr << 3;
diff --git a/drivers/gpu/drm/sun4i/sun4i_dotclock.c b/drivers/gpu/drm/sun4i/sun4i_dotclock.c
index 3ff668cb463c..5b3463197c48 100644
--- a/drivers/gpu/drm/sun4i/sun4i_dotclock.c
+++ b/drivers/gpu/drm/sun4i/sun4i_dotclock.c
@@ -72,14 +72,40 @@ static unsigned long sun4i_dclk_recalc_rate(struct clk_hw *hw,
 static long sun4i_dclk_round_rate(struct clk_hw *hw, unsigned long rate,
 				  unsigned long *parent_rate)
 {
-	return *parent_rate / DIV_ROUND_CLOSEST(*parent_rate, rate);
+	unsigned long best_parent = 0;
+	u8 best_div = 1;
+	int i;
+
+	for (i = 6; i < 127; i++) {
+		unsigned long ideal = rate * i;
+		unsigned long rounded;
+
+		rounded = clk_hw_round_rate(clk_hw_get_parent(hw),
+					    ideal);
+
+		if (rounded == ideal) {
+			best_parent = rounded;
+			best_div = i;
+			goto out;
+		}
+
+		if ((rounded < ideal) && (rounded > best_parent)) {
+			best_parent = rounded;
+			best_div = i;
+		}
+	}
+
+out:
+	*parent_rate = best_parent;
+
+	return best_parent / best_div;
 }
 
 static int sun4i_dclk_set_rate(struct clk_hw *hw, unsigned long rate,
 			       unsigned long parent_rate)
 {
 	struct sun4i_dclk *dclk = hw_to_dclk(hw);
-	int div = DIV_ROUND_CLOSEST(parent_rate, rate);
+	u8 div = parent_rate / rate;
 
 	return regmap_update_bits(dclk->regmap, SUN4I_TCON0_DCLK_REG,
 				  GENMASK(6, 0), div);
@@ -127,10 +153,14 @@ int sun4i_dclk_create(struct device *dev, struct sun4i_tcon *tcon)
 	const char *clk_name, *parent_name;
 	struct clk_init_data init;
 	struct sun4i_dclk *dclk;
+	int ret;
 
 	parent_name = __clk_get_name(tcon->sclk0);
-	of_property_read_string_index(dev->of_node, "clock-output-names", 0,
-				      &clk_name);
+	ret = of_property_read_string_index(dev->of_node,
+					    "clock-output-names", 0,
+					    &clk_name);
+	if (ret)
+		return ret;
 
 	dclk = devm_kzalloc(dev, sizeof(*dclk), GFP_KERNEL);
 	if (!dclk)
@@ -140,6 +170,7 @@ int sun4i_dclk_create(struct device *dev, struct sun4i_tcon *tcon)
 	init.ops = &sun4i_dclk_ops;
 	init.parent_names = &parent_name;
 	init.num_parents = 1;
+	init.flags = CLK_SET_RATE_PARENT;
 
 	dclk->regmap = tcon->regs;
 	dclk->hw.init = &init;
diff --git a/drivers/gpu/drm/sun4i/sun4i_drv.c b/drivers/gpu/drm/sun4i/sun4i_drv.c
index 76e922bb60e5..257d2b4f3645 100644
--- a/drivers/gpu/drm/sun4i/sun4i_drv.c
+++ b/drivers/gpu/drm/sun4i/sun4i_drv.c
@@ -24,34 +24,6 @@
 #include "sun4i_layer.h"
 #include "sun4i_tcon.h"
 
-static int sun4i_drv_connector_plug_all(struct drm_device *drm)
-{
-	struct drm_connector *connector, *failed;
-	int ret;
-
-	mutex_lock(&drm->mode_config.mutex);
-	list_for_each_entry(connector, &drm->mode_config.connector_list, head) {
-		ret = drm_connector_register(connector);
-		if (ret) {
-			failed = connector;
-			goto err;
-		}
-	}
-	mutex_unlock(&drm->mode_config.mutex);
-	return 0;
-
-err:
-	list_for_each_entry(connector, &drm->mode_config.connector_list, head) {
-		if (failed == connector)
-			break;
-
-		drm_connector_unregister(connector);
-	}
-	mutex_unlock(&drm->mode_config.mutex);
-
-	return ret;
-}
-
 static int sun4i_drv_enable_vblank(struct drm_device *drm, unsigned int pipe)
 {
 	struct sun4i_drv *drv = drm->dev_private;
@@ -125,6 +97,22 @@ static struct drm_driver sun4i_drv_driver = {
 	.disable_vblank		= sun4i_drv_disable_vblank,
 };
 
+static void sun4i_remove_framebuffers(void)
+{
+	struct apertures_struct *ap;
+
+	ap = alloc_apertures(1);
+	if (!ap)
+		return;
+
+	/* The framebuffer can be located anywhere in RAM */
+	ap->ranges[0].base = 0;
+	ap->ranges[0].size = ~0;
+
+	remove_conflicting_framebuffers(ap, "sun4i-drm-fb", false);
+	kfree(ap);
+}
+
 static int sun4i_drv_bind(struct device *dev)
 {
 	struct drm_device *drm;
@@ -172,6 +160,9 @@ static int sun4i_drv_bind(struct device *dev)
 	}
 	drm->irq_enabled = true;
 
+	/* Remove early framebuffers (ie. simplefb) */
+	sun4i_remove_framebuffers();
+
 	/* Create our framebuffer */
 	drv->fbdev = sun4i_framebuffer_init(drm);
 	if (IS_ERR(drv->fbdev)) {
@@ -187,7 +178,7 @@ static int sun4i_drv_bind(struct device *dev)
 	if (ret)
 		goto free_drm;
 
-	ret = sun4i_drv_connector_plug_all(drm);
+	ret = drm_connector_register_all(drm);
 	if (ret)
 		goto unregister_drm;
 
@@ -204,6 +195,7 @@ static void sun4i_drv_unbind(struct device *dev)
 {
 	struct drm_device *drm = dev_get_drvdata(dev);
 
+	drm_connector_unregister_all(drm);
 	drm_dev_unregister(drm);
 	drm_kms_helper_poll_fini(drm);
 	sun4i_framebuffer_free(drm);
diff --git a/drivers/gpu/drm/sun4i/sun4i_rgb.c b/drivers/gpu/drm/sun4i/sun4i_rgb.c
index ab6494818050..aaffe9e64ffb 100644
--- a/drivers/gpu/drm/sun4i/sun4i_rgb.c
+++ b/drivers/gpu/drm/sun4i/sun4i_rgb.c
@@ -54,8 +54,13 @@ static int sun4i_rgb_get_modes(struct drm_connector *connector)
 static int sun4i_rgb_mode_valid(struct drm_connector *connector,
 				struct drm_display_mode *mode)
 {
+	struct sun4i_rgb *rgb = drm_connector_to_sun4i_rgb(connector);
+	struct sun4i_drv *drv = rgb->drv;
+	struct sun4i_tcon *tcon = drv->tcon;
 	u32 hsync = mode->hsync_end - mode->hsync_start;
 	u32 vsync = mode->vsync_end - mode->vsync_start;
+	unsigned long rate = mode->clock * 1000;
+	long rounded_rate;
 
 	DRM_DEBUG_DRIVER("Validating modes...\n");
 
@@ -87,6 +92,15 @@ static int sun4i_rgb_mode_valid(struct drm_connector *connector,
 
 	DRM_DEBUG_DRIVER("Vertical parameters OK\n");
 
+	rounded_rate = clk_round_rate(tcon->dclk, rate);
+	if (rounded_rate < rate)
+		return MODE_CLOCK_LOW;
+
+	if (rounded_rate > rate)
+		return MODE_CLOCK_HIGH;
+
+	DRM_DEBUG_DRIVER("Clock rate OK\n");
+
 	return MODE_OK;
 }
 
@@ -203,7 +217,7 @@ int sun4i_rgb_init(struct drm_device *drm)
 	int ret;
 
 	/* If we don't have a panel, there's no point in going on */
-	if (!tcon->panel)
+	if (IS_ERR(tcon->panel))
 		return -ENODEV;
 
 	rgb = devm_kzalloc(drm->dev, sizeof(*rgb), GFP_KERNEL);
diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
index 9f19b0e08560..652385f09735 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
@@ -425,11 +425,11 @@ static struct drm_panel *sun4i_tcon_find_panel(struct device_node *node)
 
 	remote = of_graph_get_remote_port_parent(end_node);
 	if (!remote) {
-		DRM_DEBUG_DRIVER("Enable to parse remote node\n");
+		DRM_DEBUG_DRIVER("Unable to parse remote node\n");
 		return ERR_PTR(-EINVAL);
 	}
 
-	return of_drm_find_panel(remote);
+	return of_drm_find_panel(remote) ?: ERR_PTR(-EPROBE_DEFER);
 }
 
 static int sun4i_tcon_bind(struct device *dev, struct device *master,
@@ -490,7 +490,11 @@ static int sun4i_tcon_bind(struct device *dev, struct device *master,
 		return 0;
 	}
 
-	return sun4i_rgb_init(drm);
+	ret = sun4i_rgb_init(drm);
+	if (ret < 0)
+		goto err_free_clocks;
+
+	return 0;
 
 err_free_clocks:
 	sun4i_tcon_free_clocks(tcon);
@@ -522,12 +526,13 @@ static int sun4i_tcon_probe(struct platform_device *pdev)
 	 * Defer the probe.
 	 */
 	panel = sun4i_tcon_find_panel(node);
-	if (IS_ERR(panel)) {
-		/*
-		 * If we don't have a panel endpoint, just go on
-		 */
-		if (PTR_ERR(panel) != -ENODEV)
-			return -EPROBE_DEFER;
+
+	/*
+	 * If we don't have a panel endpoint, just go on
+	 */
+	if (PTR_ERR(panel) == -EPROBE_DEFER) {
+		DRM_DEBUG_DRIVER("Still waiting for our panel. Deferring...\n");
+		return -EPROBE_DEFER;
 	}
 
 	return component_add(&pdev->dev, &sun4i_tcon_ops);