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);