drm/bridge: ite-it6263: Move chip initialization code from probe to atomic_enable

On the RZ/G3L SMARC EVK, suspend to RAM powers down the ITE IT6263 chip.
The display controller driver's system PM callbacks invoke
drm_mode_config_helper_{suspend,resume}, which in turn call the bridge's
atomic_{disable,enable} callbacks to handle suspend/resume for the bridge
without dedicated PM ops.

To support proper reinitialization after power loss, move reset_gpio into
the it6263 struct so it is accessible beyond probe time. Relocate
it6263_hw_reset(), it6263_lvds_set_i2c_addr(), it6263_lvds_config() and
it6263_hdmi_config() from probe to atomic_enable, ensuring the chip is
fully reset and reconfigured on every enable, including after a
suspend/resume cycle.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Liu Ying <victor.liu@nxp.com>
Link: https://patch.msgid.link/20260501061200.20129-1-biju.das.jz@bp.renesas.com
Signed-off-by: Liu Ying <victor.liu@nxp.com>

diff --git a/drivers/gpu/drm/bridge/ite-it6263.c b/drivers/gpu/drm/bridge/ite-it6263.c
index 2ea49245e700e77cd7f482fb41b5f42dc0b43506..4a8268d0eac2331e7fde93b3297e08ab9a49f9ae 100644 (file)
--- a/drivers/gpu/drm/bridge/ite-it6263.c
+++ b/drivers/gpu/drm/bridge/ite-it6263.c
@@ -200,6 +200,7 @@ struct it6263 {
        struct regmap *lvds_regmap;
        struct drm_bridge bridge;
        struct drm_bridge *next_bridge;
+       struct gpio_desc *reset_gpio;
        int lvds_data_mapping;
        bool lvds_dual_link;
        bool lvds_link12_swap;
@@ -603,6 +604,15 @@ static void it6263_bridge_atomic_enable(struct drm_bridge *bridge,
        bool pclk_high;
        int i, ret;
 
+       it6263_hw_reset(it->reset_gpio);
+
+       ret = it6263_lvds_set_i2c_addr(it);
+       if (ret)
+               dev_err(it->dev, "failed to set I2C addr\n");
+
+       it6263_lvds_config(it);
+       it6263_hdmi_config(it);
+
        connector = drm_atomic_get_new_connector_for_encoder(state,
                                                             bridge->encoder);
        crtc = drm_atomic_get_new_connector_state(state, connector)->crtc;
@@ -838,7 +848,6 @@ static const struct drm_bridge_funcs it6263_bridge_funcs = {
 static int it6263_probe(struct i2c_client *client)
 {
        struct device *dev = &client->dev;
-       struct gpio_desc *reset_gpio;
        struct it6263 *it;
        int ret;
 
@@ -856,9 +865,9 @@ static int it6263_probe(struct i2c_client *client)
                return dev_err_probe(dev, PTR_ERR(it->hdmi_regmap),
                                     "failed to init I2C regmap for HDMI\n");
 
-       reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
-       if (IS_ERR(reset_gpio))
-               return dev_err_probe(dev, PTR_ERR(reset_gpio),
+       it->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
+       if (IS_ERR(it->reset_gpio))
+               return dev_err_probe(dev, PTR_ERR(it->reset_gpio),
                                     "failed to get reset gpio\n");
 
        ret = devm_regulator_bulk_get_enable(dev, ARRAY_SIZE(it6263_supplies),
@@ -870,12 +879,6 @@ static int it6263_probe(struct i2c_client *client)
        if (ret)
                return ret;
 
-       it6263_hw_reset(reset_gpio);
-
-       ret = it6263_lvds_set_i2c_addr(it);
-       if (ret)
-               return dev_err_probe(dev, ret, "failed to set I2C addr\n");
-
        it->lvds_i2c = devm_i2c_new_dummy_device(dev, client->adapter,
                                                 LVDS_INPUT_CTRL_I2C_ADDR);
        if (IS_ERR(it->lvds_i2c))
@@ -888,9 +891,6 @@ static int it6263_probe(struct i2c_client *client)
                return dev_err_probe(dev, PTR_ERR(it->lvds_regmap),
                                     "failed to init I2C regmap for LVDS\n");
 
-       it6263_lvds_config(it);
-       it6263_hdmi_config(it);
-
        i2c_set_clientdata(client, it);
 
        it->bridge.of_node = dev->of_node;