drm/bridge: ptn3460: Convert to I2C driver model

Use drm_bridge helpers to modify the driver to support I2C driver model.

Signed-off-by: Ajay Kumar <ajaykumar.rs@samsung.com>
Acked-by: Inki Dae <inki.dae@samsung.com>
Tested-by: Rahul Sharma <rahul.sharma@samsung.com>
Tested-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Tested-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Tested-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
[treding@nvidia.com: remove recursive dependency on I2C]
Signed-off-by: Thierry Reding <treding@nvidia.com>

3 files changed, 91 insertions, 67 deletions

diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index b70f3c8d4e8a..ffa3e061a618 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -1,10 +1,12 @@
-config DRM_PTN3460
-        tristate "PTN3460 DP/LVDS bridge"
+config DRM_DW_HDMI
+        tristate
         depends on DRM
         select DRM_KMS_HELPER
-        ---help---
 
-config DRM_DW_HDMI
-        tristate
+config DRM_PTN3460
+        tristate "PTN3460 DP/LVDS bridge"
         depends on DRM
+        depends on OF
         select DRM_KMS_HELPER
+        ---help---
+          ptn3460 eDP-LVDS bridge chip driver.
diff --git a/drivers/gpu/drm/bridge/ptn3460.c b/drivers/gpu/drm/bridge/ptn3460.c
index 4a818c1b62e0..7adeb607f6fb 100644
--- a/drivers/gpu/drm/bridge/ptn3460.c
+++ b/drivers/gpu/drm/bridge/ptn3460.c
@@ -36,7 +36,6 @@
 struct ptn3460_bridge {
         struct drm_connector connector;
         struct i2c_client *client;
-        struct drm_encoder *encoder;
         struct drm_bridge bridge;
         struct edid *edid;
         int gpio_pd_n;
@@ -176,13 +175,6 @@ static void ptn3460_post_disable(struct drm_bridge *bridge)
 {
 }
 
-static struct drm_bridge_funcs ptn3460_bridge_funcs = {
-        .pre_enable = ptn3460_pre_enable,
-        .enable = ptn3460_enable,
-        .disable = ptn3460_disable,
-        .post_disable = ptn3460_post_disable,
-};
-
 static int ptn3460_get_modes(struct drm_connector *connector)
 {
         struct ptn3460_bridge *ptn_bridge;
@@ -227,7 +219,7 @@ static struct drm_encoder *ptn3460_best_encoder(struct drm_connector *connector)
 {
         struct ptn3460_bridge *ptn_bridge = connector_to_ptn3460(connector);
 
-        return ptn_bridge->encoder;
+        return ptn_bridge->bridge.encoder;
 }
 
 static struct drm_connector_helper_funcs ptn3460_connector_helper_funcs = {
@@ -253,31 +245,66 @@ static struct drm_connector_funcs ptn3460_connector_funcs = {
         .destroy = ptn3460_connector_destroy,
 };
 
-int ptn3460_init(struct drm_device *dev, struct drm_encoder *encoder,
-                struct i2c_client *client, struct device_node *node)
+int ptn3460_bridge_attach(struct drm_bridge *bridge)
 {
+        struct ptn3460_bridge *ptn_bridge = bridge_to_ptn3460(bridge);
         int ret;
+
+        if (!bridge->encoder) {
+                DRM_ERROR("Parent encoder object not found");
+                return -ENODEV;
+        }
+
+        ret = drm_connector_init(bridge->dev, &ptn_bridge->connector,
+                        &ptn3460_connector_funcs, DRM_MODE_CONNECTOR_LVDS);
+        if (ret) {
+                DRM_ERROR("Failed to initialize connector with drm\n");
+                return ret;
+        }
+        drm_connector_helper_add(&ptn_bridge->connector,
+                                        &ptn3460_connector_helper_funcs);
+        drm_connector_register(&ptn_bridge->connector);
+        drm_mode_connector_attach_encoder(&ptn_bridge->connector,
+                                                        bridge->encoder);
+
+        return ret;
+}
+
+static struct drm_bridge_funcs ptn3460_bridge_funcs = {
+        .pre_enable = ptn3460_pre_enable,
+        .enable = ptn3460_enable,
+        .disable = ptn3460_disable,
+        .post_disable = ptn3460_post_disable,
+        .attach = ptn3460_bridge_attach,
+};
+
+static int ptn3460_probe(struct i2c_client *client,
+                                const struct i2c_device_id *id)
+{
+        struct device *dev = &client->dev;
         struct ptn3460_bridge *ptn_bridge;
+        int ret;
 
-        ptn_bridge = devm_kzalloc(dev->dev, sizeof(*ptn_bridge), GFP_KERNEL);
+        ptn_bridge = devm_kzalloc(dev, sizeof(*ptn_bridge), GFP_KERNEL);
         if (!ptn_bridge) {
                 return -ENOMEM;
         }
 
         ptn_bridge->client = client;
-        ptn_bridge->encoder = encoder;
-        ptn_bridge->gpio_pd_n = of_get_named_gpio(node, "powerdown-gpio", 0);
+        ptn_bridge->gpio_pd_n = of_get_named_gpio(dev->of_node,
+                                                        "powerdown-gpio", 0);
         if (gpio_is_valid(ptn_bridge->gpio_pd_n)) {
                 ret = gpio_request_one(ptn_bridge->gpio_pd_n,
                                 GPIOF_OUT_INIT_HIGH, "PTN3460_PD_N");
                 if (ret) {
-                        dev_err(&client->dev,
-                                "Request powerdown-gpio failed (%d)\n", ret);
+                        dev_err(dev, "Request powerdown-gpio failed (%d)\n",
+                                                                        ret);
                         return ret;
                 }
         }
 
-        ptn_bridge->gpio_rst_n = of_get_named_gpio(node, "reset-gpio", 0);
+        ptn_bridge->gpio_rst_n = of_get_named_gpio(dev->of_node,
+                                                        "reset-gpio", 0);
         if (gpio_is_valid(ptn_bridge->gpio_rst_n)) {
                 /*
                  * Request the reset pin low to avoid the bridge being
@@ -286,39 +313,27 @@ int ptn3460_init(struct drm_device *dev, struct drm_encoder *encoder,
                 ret = gpio_request_one(ptn_bridge->gpio_rst_n,
                                 GPIOF_OUT_INIT_LOW, "PTN3460_RST_N");
                 if (ret) {
-                        dev_err(&client->dev,
-                                "Request reset-gpio failed (%d)\n", ret);
+                        dev_err(dev, "Request reset-gpio failed (%d)\n", ret);
                         gpio_free(ptn_bridge->gpio_pd_n);
                         return ret;
                 }
         }
 
-        ret = of_property_read_u32(node, "edid-emulation",
+        ret = of_property_read_u32(dev->of_node, "edid-emulation",
                         &ptn_bridge->edid_emulation);
         if (ret) {
-                dev_err(&client->dev, "Can't read EDID emulation value\n");
+                dev_err(dev, "Can't read EDID emulation value\n");
                 goto err;
         }
 
         ptn_bridge->bridge.funcs = &ptn3460_bridge_funcs;
-        ret = drm_bridge_attach(dev, &ptn_bridge->bridge);
+        ret = drm_bridge_add(&ptn_bridge->bridge);
         if (ret) {
-                DRM_ERROR("Failed to initialize bridge with drm\n");
+                DRM_ERROR("Failed to add bridge\n");
                 goto err;
         }
 
-        encoder->bridge = &ptn_bridge->bridge;
-
-        ret = drm_connector_init(dev, &ptn_bridge->connector,
-                        &ptn3460_connector_funcs, DRM_MODE_CONNECTOR_LVDS);
-        if (ret) {
-                DRM_ERROR("Failed to initialize connector with drm\n");
-                goto err;
-        }
-        drm_connector_helper_add(&ptn_bridge->connector,
-                        &ptn3460_connector_helper_funcs);
-        drm_connector_register(&ptn_bridge->connector);
-        drm_mode_connector_attach_encoder(&ptn_bridge->connector, encoder);
+        i2c_set_clientdata(client, ptn_bridge);
 
         return 0;
 
@@ -329,16 +344,45 @@ err:
                 gpio_free(ptn_bridge->gpio_rst_n);
         return ret;
 }
-EXPORT_SYMBOL(ptn3460_init);
 
-void ptn3460_destroy(struct drm_bridge *bridge)
+static int ptn3460_remove(struct i2c_client *client)
 {
-        struct ptn3460_bridge *ptn_bridge = bridge->driver_private;
+        struct ptn3460_bridge *ptn_bridge = i2c_get_clientdata(client);
+
+        drm_bridge_remove(&ptn_bridge->bridge);
 
         if (gpio_is_valid(ptn_bridge->gpio_pd_n))
                 gpio_free(ptn_bridge->gpio_pd_n);
         if (gpio_is_valid(ptn_bridge->gpio_rst_n))
                 gpio_free(ptn_bridge->gpio_rst_n);
-        /* Nothing else to free, we've got devm allocated memory */
+
+        return 0;
 }
-EXPORT_SYMBOL(ptn3460_destroy);
+
+static const struct i2c_device_id ptn3460_i2c_table[] = {
+        {"nxp,ptn3460", 0},
+        {},
+};
+MODULE_DEVICE_TABLE(i2c, ptn3460_i2c_table);
+
+static const struct of_device_id ptn3460_match[] = {
+        { .compatible = "nxp,ptn3460" },
+        {},
+};
+MODULE_DEVICE_TABLE(of, ptn3460_match);
+
+static struct i2c_driver ptn3460_driver = {
+        .id_table       = ptn3460_i2c_table,
+        .probe          = ptn3460_probe,
+        .remove         = ptn3460_remove,
+        .driver         = {
+                .name   = "nxp,ptn3460",
+                .owner  = THIS_MODULE,
+                .of_match_table = ptn3460_match,
+        },
+};
+module_i2c_driver(ptn3460_driver);
+
+MODULE_AUTHOR("Sean Paul <seanpaul@chromium.org>");
+MODULE_DESCRIPTION("NXP ptn3460 eDP-LVDS converter driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/gpu/drm/exynos/exynos_dp_core.c b/drivers/gpu/drm/exynos/exynos_dp_core.c
index 34d46aa75416..27e3d272ca2d 100644
--- a/drivers/gpu/drm/exynos/exynos_dp_core.c
+++ b/drivers/gpu/drm/exynos/exynos_dp_core.c
@@ -993,32 +993,10 @@ static struct drm_connector_helper_funcs exynos_dp_connector_helper_funcs = {
         .best_encoder = exynos_dp_best_encoder,
 };
 
-static bool find_bridge(const char *compat, struct bridge_init *bridge)
-{
-        bridge->client = NULL;
-        bridge->node = of_find_compatible_node(NULL, NULL, compat);
-        if (!bridge->node)
-                return false;
-
-        bridge->client = of_find_i2c_device_by_node(bridge->node);
-        if (!bridge->client)
-                return false;
-
-        return true;
-}
-
 /* returns the number of bridges attached */
 static int exynos_drm_attach_lcd_bridge(struct drm_device *dev,
                 struct drm_encoder *encoder)
 {
-        struct bridge_init bridge;
-        int ret;
-
-        if (find_bridge("nxp,ptn3460", &bridge)) {
-                ret = ptn3460_init(dev, encoder, bridge.client, bridge.node);
-                if (!ret)
-                        return 1;
-        }
         return 0;
 }