[PATCH 1/3] drm/bridge: tc358767: Handle dsi_lanes == 0 as invalid

[PATCH 1/3] drm/bridge: tc358767: Handle dsi_lanes == 0 as invalid

[Marek Vasut]

Handle empty data-lanes = < >; property, which translates to
dsi_lanes = 0 as invalid.

Fixes: bbfd3190b6562 ("drm/bridge: tc358767: Add DSI-to-DPI mode support")
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Jonas Karlman <jonas@kwiboo.se>
Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Marek Vasut <marex@denx.de>
Cc: Maxime Ripard <maxime@cerno.tech>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Robert Foss <robert.foss@linaro.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
---
 drivers/gpu/drm/bridge/tc358767.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c
index 7366968dd7b21..84e6b5aa8dd1f 100644
--- a/drivers/gpu/drm/bridge/tc358767.c
+++ b/drivers/gpu/drm/bridge/tc358767.c
@@ -1902,7 +1902,7 @@ static int tc_mipi_dsi_host_attach(struct tc_data *tc)
 	of_node_put(host_node);
 	of_node_put(endpoint);
 
-	if (dsi_lanes < 0 || dsi_lanes > 4)
+	if (dsi_lanes <= 0 || dsi_lanes > 4)
 		return -EINVAL;
 
 	if (!host)
-- 
2.35.1

[PATCH 2/3] drm/bridge: tc358767: Report DSI-to-(e)DP as supported

[Marek Vasut]

The DSI-to-e(DP) mode is now supported, update the driver comment
to reflect this. No functional change.

Fixes: 3080c21a043ab ("drm/bridge: tc358767: Add DSI-to-(e)DP mode support")
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Jonas Karlman <jonas@kwiboo.se>
Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Marek Vasut <marex@denx.de>
Cc: Maxime Ripard <maxime@cerno.tech>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Robert Foss <robert.foss@linaro.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
---
 drivers/gpu/drm/bridge/tc358767.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c
index 84e6b5aa8dd1f..a8bb6de9e600a 100644
--- a/drivers/gpu/drm/bridge/tc358767.c
+++ b/drivers/gpu/drm/bridge/tc358767.c
@@ -6,7 +6,7 @@
  * The following modes are supported:
  *   DPI->(e)DP -- supported
  *   DSI->DPI .... supported
- *   DSI->(e)DP .. NOT supported
+ *   DSI->(e)DP .. supported
  *
  * Copyright (C) 2016 CogentEmbedded Inc
  * Author: Andrey Gusakov <andrey.gusakov@cogentembedded.com>
-- 
2.35.1

[PATCH 3/3] drm/bridge: tc358767: Make sure Refclk clock are enabled

[Marek Vasut]

The Refclk may be supplied by SoC clock output instead of crystal
oscillator, make sure the clock are enabled before any other action
is performed with the bridge chip, otherwise it may either fail to
operate at all, or miss reset GPIO toggle.

Fixes: 7caff0fc4296e ("drm/bridge: tc358767: Add DPI to eDP bridge driver")
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Jonas Karlman <jonas@kwiboo.se>
Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Marek Vasut <marex@denx.de>
Cc: Maxime Ripard <maxime@cerno.tech>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Robert Foss <robert.foss@linaro.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
---
 drivers/gpu/drm/bridge/tc358767.c | 51 ++++++++++++++++++++-----------
 1 file changed, 33 insertions(+), 18 deletions(-)

diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c
index a8bb6de9e600a..4b15acbc73c4e 100644
--- a/drivers/gpu/drm/bridge/tc358767.c
+++ b/drivers/gpu/drm/bridge/tc358767.c
@@ -2055,10 +2055,24 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
 	if (ret)
 		return ret;
 
+	tc->refclk = devm_clk_get(dev, "ref");
+	if (IS_ERR(tc->refclk)) {
+		ret = PTR_ERR(tc->refclk);
+		dev_err(dev, "Failed to get refclk: %d\n", ret);
+		return ret;
+	}
+
+	clk_prepare_enable(tc->refclk);
+
+	/* tRSTW = 100 cycles , at 13 MHz that is ~7.69 us */
+	usleep_range(10, 15);
+
 	/* Shut down GPIO is optional */
 	tc->sd_gpio = devm_gpiod_get_optional(dev, "shutdown", GPIOD_OUT_HIGH);
-	if (IS_ERR(tc->sd_gpio))
-		return PTR_ERR(tc->sd_gpio);
+	if (IS_ERR(tc->sd_gpio)) {
+		ret = PTR_ERR(tc->sd_gpio);
+		goto err_clk;
+	}
 
 	if (tc->sd_gpio) {
 		gpiod_set_value_cansleep(tc->sd_gpio, 0);
@@ -2067,26 +2081,21 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
 
 	/* Reset GPIO is optional */
 	tc->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
-	if (IS_ERR(tc->reset_gpio))
-		return PTR_ERR(tc->reset_gpio);
+	if (IS_ERR(tc->reset_gpio)) {
+		ret = PTR_ERR(tc->reset_gpio);
+		goto err_clk;
+	}
 
 	if (tc->reset_gpio) {
 		gpiod_set_value_cansleep(tc->reset_gpio, 1);
 		usleep_range(5000, 10000);
 	}
 
-	tc->refclk = devm_clk_get(dev, "ref");
-	if (IS_ERR(tc->refclk)) {
-		ret = PTR_ERR(tc->refclk);
-		dev_err(dev, "Failed to get refclk: %d\n", ret);
-		return ret;
-	}
-
 	tc->regmap = devm_regmap_init_i2c(client, &tc_regmap_config);
 	if (IS_ERR(tc->regmap)) {
 		ret = PTR_ERR(tc->regmap);
 		dev_err(dev, "Failed to initialize regmap: %d\n", ret);
-		return ret;
+		goto err_clk;
 	}
 
 	ret = of_property_read_u32(dev->of_node, "toshiba,hpd-pin",
@@ -2096,7 +2105,7 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
 	} else {
 		if (tc->hpd_pin < 0 || tc->hpd_pin > 1) {
 			dev_err(dev, "failed to parse HPD number\n");
-			return ret;
+			goto err_clk;
 		}
 	}
 
@@ -2110,7 +2119,7 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
 						"tc358767-irq", tc);
 		if (ret) {
 			dev_err(dev, "failed to register dp interrupt\n");
-			return ret;
+			goto err_clk;
 		}
 
 		tc->have_irq = true;
@@ -2119,12 +2128,13 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
 	ret = regmap_read(tc->regmap, TC_IDREG, &tc->rev);
 	if (ret) {
 		dev_err(tc->dev, "can not read device ID: %d\n", ret);
-		return ret;
+		goto err_clk;
 	}
 
 	if ((tc->rev != 0x6601) && (tc->rev != 0x6603)) {
 		dev_err(tc->dev, "invalid device ID: 0x%08x\n", tc->rev);
-		return -EINVAL;
+		ret = -EINVAL;
+		goto err_clk;
 	}
 
 	tc->assr = (tc->rev == 0x6601); /* Enable ASSR for eDP panels */
@@ -2164,7 +2174,7 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
 	if (tc->bridge.type != DRM_MODE_CONNECTOR_DPI) { /* (e)DP output */
 		ret = tc_aux_link_setup(tc);
 		if (ret)
-			return ret;
+			goto err_clk;
 	}
 
 	tc->bridge.of_node = dev->of_node;
@@ -2176,11 +2186,15 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
 		ret = tc_mipi_dsi_host_attach(tc);
 		if (ret) {
 			drm_bridge_remove(&tc->bridge);
-			return ret;
+			goto err_clk;
 		}
 	}
 
 	return 0;
+
+err_clk:
+	clk_disable_unprepare(tc->refclk);
+	return ret;
 }
 
 static int tc_remove(struct i2c_client *client)
@@ -2188,6 +2202,7 @@ static int tc_remove(struct i2c_client *client)
 	struct tc_data *tc = i2c_get_clientdata(client);
 
 	drm_bridge_remove(&tc->bridge);
+	clk_disable_unprepare(tc->refclk);
 
 	return 0;
 }
-- 
2.35.1

Re: [PATCH 1/3] drm/bridge: tc358767: Handle dsi_lanes == 0 as invalid

[Andrzej Hajda]

On 19.05.2022 01:36, Marek Vasut wrote:
> Handle empty data-lanes = < >; property, which translates to
> dsi_lanes = 0 as invalid.
> 
> Fixes: bbfd3190b6562 ("drm/bridge: tc358767: Add DSI-to-DPI mode support")
> Signed-off-by: Marek Vasut <marex@denx.de>
> Cc: Jonas Karlman <jonas@kwiboo.se>
> Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
> Cc: Lucas Stach <l.stach@pengutronix.de>
> Cc: Marek Vasut <marex@denx.de>
> Cc: Maxime Ripard <maxime@cerno.tech>
> Cc: Neil Armstrong <narmstrong@baylibre.com>
> Cc: Robert Foss <robert.foss@linaro.org>
> Cc: Sam Ravnborg <sam@ravnborg.org>

Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>

Regards
Andrzej
> ---
>   drivers/gpu/drm/bridge/tc358767.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c
> index 7366968dd7b21..84e6b5aa8dd1f 100644
> --- a/drivers/gpu/drm/bridge/tc358767.c
> +++ b/drivers/gpu/drm/bridge/tc358767.c
> @@ -1902,7 +1902,7 @@ static int tc_mipi_dsi_host_attach(struct tc_data *tc)
>   	of_node_put(host_node);
>   	of_node_put(endpoint);
>   
> -	if (dsi_lanes < 0 || dsi_lanes > 4)
> +	if (dsi_lanes <= 0 || dsi_lanes > 4)
>   		return -EINVAL;
>   
>   	if (!host)

Re: [PATCH 2/3] drm/bridge: tc358767: Report DSI-to-(e)DP as supported

[Andrzej Hajda]

On 19.05.2022 01:36, Marek Vasut wrote:
> The DSI-to-e(DP) mode is now supported, update the driver comment
> to reflect this. No functional change.
> 
> Fixes: 3080c21a043ab ("drm/bridge: tc358767: Add DSI-to-(e)DP mode support")
> Signed-off-by: Marek Vasut <marex@denx.de>
> Cc: Jonas Karlman <jonas@kwiboo.se>
> Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
> Cc: Lucas Stach <l.stach@pengutronix.de>
> Cc: Marek Vasut <marex@denx.de>
> Cc: Maxime Ripard <maxime@cerno.tech>
> Cc: Neil Armstrong <narmstrong@baylibre.com>
> Cc: Robert Foss <robert.foss@linaro.org>
> Cc: Sam Ravnborg <sam@ravnborg.org>
> ---
>   drivers/gpu/drm/bridge/tc358767.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c
> index 84e6b5aa8dd1f..a8bb6de9e600a 100644
> --- a/drivers/gpu/drm/bridge/tc358767.c
> +++ b/drivers/gpu/drm/bridge/tc358767.c
> @@ -6,7 +6,7 @@
>    * The following modes are supported:
>    *   DPI->(e)DP -- supported
>    *   DSI->DPI .... supported
> - *   DSI->(e)DP .. NOT supported
> + *   DSI->(e)DP .. supported

Since everything is supported(?) this message becomes useless, or can be 
shortened. With or w/o:

Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>

Regards
Andrzej

>    *
>    * Copyright (C) 2016 CogentEmbedded Inc
>    * Author: Andrey Gusakov <andrey.gusakov@cogentembedded.com>

Re: [PATCH 1/3] drm/bridge: tc358767: Handle dsi_lanes == 0 as invalid

[Lucas Stach]

Am Donnerstag, dem 19.05.2022 um 01:36 +0200 schrieb Marek Vasut:
> Handle empty data-lanes = < >; property, which translates to
> dsi_lanes = 0 as invalid.
> 
I'm having a hard time imagining a situation where on would add a empty
data-lanes property to the DT. But then 0 DSI lanes is clearly a broken
configuration, so:

Reviewed-by: Lucas Stach <l.stach@pengutronix.de>

> Fixes: bbfd3190b6562 ("drm/bridge: tc358767: Add DSI-to-DPI mode support")
> Signed-off-by: Marek Vasut <marex@denx.de>
> Cc: Jonas Karlman <jonas@kwiboo.se>
> Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
> Cc: Lucas Stach <l.stach@pengutronix.de>
> Cc: Marek Vasut <marex@denx.de>
> Cc: Maxime Ripard <maxime@cerno.tech>
> Cc: Neil Armstrong <narmstrong@baylibre.com>
> Cc: Robert Foss <robert.foss@linaro.org>
> Cc: Sam Ravnborg <sam@ravnborg.org>
> ---
>  drivers/gpu/drm/bridge/tc358767.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c
> index 7366968dd7b21..84e6b5aa8dd1f 100644
> --- a/drivers/gpu/drm/bridge/tc358767.c
> +++ b/drivers/gpu/drm/bridge/tc358767.c
> @@ -1902,7 +1902,7 @@ static int tc_mipi_dsi_host_attach(struct tc_data *tc)
>  	of_node_put(host_node);
>  	of_node_put(endpoint);
>  
> -	if (dsi_lanes < 0 || dsi_lanes > 4)
> +	if (dsi_lanes <= 0 || dsi_lanes > 4)
>  		return -EINVAL;
>  
>  	if (!host)

Re: [PATCH 2/3] drm/bridge: tc358767: Report DSI-to-(e)DP as supported

[Lucas Stach]

Am Donnerstag, dem 19.05.2022 um 01:36 +0200 schrieb Marek Vasut:
> The DSI-to-e(DP) mode is now supported, update the driver comment
> to reflect this. No functional change.
> 
> Fixes: 3080c21a043ab ("drm/bridge: tc358767: Add DSI-to-(e)DP mode support")
> Signed-off-by: Marek Vasut <marex@denx.de>
> Cc: Jonas Karlman <jonas@kwiboo.se>
> Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
> Cc: Lucas Stach <l.stach@pengutronix.de>
> Cc: Marek Vasut <marex@denx.de>
> Cc: Maxime Ripard <maxime@cerno.tech>
> Cc: Neil Armstrong <narmstrong@baylibre.com>
> Cc: Robert Foss <robert.foss@linaro.org>
> Cc: Sam Ravnborg <sam@ravnborg.org>
> ---
>  drivers/gpu/drm/bridge/tc358767.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c
> index 84e6b5aa8dd1f..a8bb6de9e600a 100644
> --- a/drivers/gpu/drm/bridge/tc358767.c
> +++ b/drivers/gpu/drm/bridge/tc358767.c
> @@ -6,7 +6,7 @@
>   * The following modes are supported:
>   *   DPI->(e)DP -- supported
>   *   DSI->DPI .... supported
> - *   DSI->(e)DP .. NOT supported
> + *   DSI->(e)DP .. supported

Couldn't we just drop the status behind the modes when the line above
already states that those modes are supported, which is now true for
all of them? But I then also don't care too much about it, so if you
like your version better, feel free to commit with:

Reviewed-by: Lucas Stach <l.stach@pengutronix.de> 

>   *
>   * Copyright (C) 2016 CogentEmbedded Inc
>   * Author: Andrey Gusakov <andrey.gusakov@cogentembedded.com>

Re: [PATCH 3/3] drm/bridge: tc358767: Make sure Refclk clock are enabled

[Lucas Stach]

Am Donnerstag, dem 19.05.2022 um 01:36 +0200 schrieb Marek Vasut:
> The Refclk may be supplied by SoC clock output instead of crystal
> oscillator, make sure the clock are enabled before any other action
> is performed with the bridge chip, otherwise it may either fail to
> operate at all, or miss reset GPIO toggle.
> 
> Fixes: 7caff0fc4296e ("drm/bridge: tc358767: Add DPI to eDP bridge driver")
> Signed-off-by: Marek Vasut <marex@denx.de>
> Cc: Jonas Karlman <jonas@kwiboo.se>
> Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
> Cc: Lucas Stach <l.stach@pengutronix.de>
> Cc: Marek Vasut <marex@denx.de>
> Cc: Maxime Ripard <maxime@cerno.tech>
> Cc: Neil Armstrong <narmstrong@baylibre.com>
> Cc: Robert Foss <robert.foss@linaro.org>
> Cc: Sam Ravnborg <sam@ravnborg.org>
> ---
>  drivers/gpu/drm/bridge/tc358767.c | 51 ++++++++++++++++++++-----------
>  1 file changed, 33 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c
> index a8bb6de9e600a..4b15acbc73c4e 100644
> --- a/drivers/gpu/drm/bridge/tc358767.c
> +++ b/drivers/gpu/drm/bridge/tc358767.c
> @@ -2055,10 +2055,24 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
>  	if (ret)
>  		return ret;
>  
> +	tc->refclk = devm_clk_get(dev, "ref");
> +	if (IS_ERR(tc->refclk)) {
> +		ret = PTR_ERR(tc->refclk);
> +		dev_err(dev, "Failed to get refclk: %d\n", ret);
> +		return ret;
> +	}
> +
> +	clk_prepare_enable(tc->refclk);
> +
> +	/* tRSTW = 100 cycles , at 13 MHz that is ~7.69 us */
> +	usleep_range(10, 15);
> +
>  	/* Shut down GPIO is optional */
>  	tc->sd_gpio = devm_gpiod_get_optional(dev, "shutdown", GPIOD_OUT_HIGH);
> -	if (IS_ERR(tc->sd_gpio))
> -		return PTR_ERR(tc->sd_gpio);
> +	if (IS_ERR(tc->sd_gpio)) {
> +		ret = PTR_ERR(tc->sd_gpio);
> +		goto err_clk;
> +	}
>  
>  	if (tc->sd_gpio) {
>  		gpiod_set_value_cansleep(tc->sd_gpio, 0);
> @@ -2067,26 +2081,21 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
>  
>  	/* Reset GPIO is optional */
>  	tc->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
> -	if (IS_ERR(tc->reset_gpio))
> -		return PTR_ERR(tc->reset_gpio);
> +	if (IS_ERR(tc->reset_gpio)) {
> +		ret = PTR_ERR(tc->reset_gpio);
> +		goto err_clk;
> +	}
>  
>  	if (tc->reset_gpio) {
>  		gpiod_set_value_cansleep(tc->reset_gpio, 1);
>  		usleep_range(5000, 10000);
>  	}
>  
> -	tc->refclk = devm_clk_get(dev, "ref");
> -	if (IS_ERR(tc->refclk)) {
> -		ret = PTR_ERR(tc->refclk);
> -		dev_err(dev, "Failed to get refclk: %d\n", ret);
> -		return ret;
> -	}
> -
>  	tc->regmap = devm_regmap_init_i2c(client, &tc_regmap_config);
>  	if (IS_ERR(tc->regmap)) {
>  		ret = PTR_ERR(tc->regmap);
>  		dev_err(dev, "Failed to initialize regmap: %d\n", ret);
> -		return ret;
> +		goto err_clk;
>  	}
>  
>  	ret = of_property_read_u32(dev->of_node, "toshiba,hpd-pin",
> @@ -2096,7 +2105,7 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
>  	} else {
>  		if (tc->hpd_pin < 0 || tc->hpd_pin > 1) {
>  			dev_err(dev, "failed to parse HPD number\n");
> -			return ret;
> +			goto err_clk;
>  		}
>  	}
>  
> @@ -2110,7 +2119,7 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
>  						"tc358767-irq", tc);
>  		if (ret) {
>  			dev_err(dev, "failed to register dp interrupt\n");
> -			return ret;
> +			goto err_clk;
>  		}
>  
>  		tc->have_irq = true;
> @@ -2119,12 +2128,13 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
>  	ret = regmap_read(tc->regmap, TC_IDREG, &tc->rev);
>  	if (ret) {
>  		dev_err(tc->dev, "can not read device ID: %d\n", ret);
> -		return ret;
> +		goto err_clk;
>  	}
>  
>  	if ((tc->rev != 0x6601) && (tc->rev != 0x6603)) {
>  		dev_err(tc->dev, "invalid device ID: 0x%08x\n", tc->rev);
> -		return -EINVAL;
> +		ret = -EINVAL;
> +		goto err_clk;
>  	}
>  
>  	tc->assr = (tc->rev == 0x6601); /* Enable ASSR for eDP panels */
> @@ -2164,7 +2174,7 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
>  	if (tc->bridge.type != DRM_MODE_CONNECTOR_DPI) { /* (e)DP output */
>  		ret = tc_aux_link_setup(tc);
>  		if (ret)
> -			return ret;
> +			goto err_clk;
>  	}
>  
>  	tc->bridge.of_node = dev->of_node;
> @@ -2176,11 +2186,15 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
>  		ret = tc_mipi_dsi_host_attach(tc);
>  		if (ret) {
>  			drm_bridge_remove(&tc->bridge);
> -			return ret;
> +			goto err_clk;
>  		}
>  	}
>  
>  	return 0;
> +
> +err_clk:
> +	clk_disable_unprepare(tc->refclk);
> +	return ret;

That's a lot of error paths to disable a effectively always-on clock
when something goes wrong. Could you maybe simplify this by using
devm_add_action_or_reset for the clock disable? Seems like lots of
watchdog drivers do this already if you need some inspiration.

Regards,
Lucas

>  }
>  
>  static int tc_remove(struct i2c_client *client)
> @@ -2188,6 +2202,7 @@ static int tc_remove(struct i2c_client *client)
>  	struct tc_data *tc = i2c_get_clientdata(client);
>  
>  	drm_bridge_remove(&tc->bridge);
> +	clk_disable_unprepare(tc->refclk);
>  
>  	return 0;
>  }

Re: [PATCH 1/3] drm/bridge: tc358767: Handle dsi_lanes == 0 as invalid

[Marek Vasut]

On 5/19/22 09:50, Lucas Stach wrote:
> Am Donnerstag, dem 19.05.2022 um 01:36 +0200 schrieb Marek Vasut:
>> Handle empty data-lanes = < >; property, which translates to
>> dsi_lanes = 0 as invalid.
>>
> I'm having a hard time imagining a situation where on would add a empty
> data-lanes property to the DT.

Like when you make a typo for example .

Re: [PATCH 3/3] drm/bridge: tc358767: Make sure Refclk clock are enabled

[Marek Vasut]

On 5/19/22 09:57, Lucas Stach wrote:
> Am Donnerstag, dem 19.05.2022 um 01:36 +0200 schrieb Marek Vasut:
>> The Refclk may be supplied by SoC clock output instead of crystal
>> oscillator, make sure the clock are enabled before any other action
>> is performed with the bridge chip, otherwise it may either fail to
>> operate at all, or miss reset GPIO toggle.
>>
>> Fixes: 7caff0fc4296e ("drm/bridge: tc358767: Add DPI to eDP bridge driver")
>> Signed-off-by: Marek Vasut <marex@denx.de>
>> Cc: Jonas Karlman <jonas@kwiboo.se>
>> Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
>> Cc: Lucas Stach <l.stach@pengutronix.de>
>> Cc: Marek Vasut <marex@denx.de>
>> Cc: Maxime Ripard <maxime@cerno.tech>
>> Cc: Neil Armstrong <narmstrong@baylibre.com>
>> Cc: Robert Foss <robert.foss@linaro.org>
>> Cc: Sam Ravnborg <sam@ravnborg.org>
>> ---
>>   drivers/gpu/drm/bridge/tc358767.c | 51 ++++++++++++++++++++-----------
>>   1 file changed, 33 insertions(+), 18 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c
>> index a8bb6de9e600a..4b15acbc73c4e 100644
>> --- a/drivers/gpu/drm/bridge/tc358767.c
>> +++ b/drivers/gpu/drm/bridge/tc358767.c
>> @@ -2055,10 +2055,24 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
>>   	if (ret)
>>   		return ret;
>>   
>> +	tc->refclk = devm_clk_get(dev, "ref");
>> +	if (IS_ERR(tc->refclk)) {
>> +		ret = PTR_ERR(tc->refclk);
>> +		dev_err(dev, "Failed to get refclk: %d\n", ret);
>> +		return ret;
>> +	}
>> +
>> +	clk_prepare_enable(tc->refclk);
>> +
>> +	/* tRSTW = 100 cycles , at 13 MHz that is ~7.69 us */
>> +	usleep_range(10, 15);
>> +
>>   	/* Shut down GPIO is optional */
>>   	tc->sd_gpio = devm_gpiod_get_optional(dev, "shutdown", GPIOD_OUT_HIGH);
>> -	if (IS_ERR(tc->sd_gpio))
>> -		return PTR_ERR(tc->sd_gpio);
>> +	if (IS_ERR(tc->sd_gpio)) {
>> +		ret = PTR_ERR(tc->sd_gpio);
>> +		goto err_clk;
>> +	}
>>   
>>   	if (tc->sd_gpio) {
>>   		gpiod_set_value_cansleep(tc->sd_gpio, 0);
>> @@ -2067,26 +2081,21 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
>>   
>>   	/* Reset GPIO is optional */
>>   	tc->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
>> -	if (IS_ERR(tc->reset_gpio))
>> -		return PTR_ERR(tc->reset_gpio);
>> +	if (IS_ERR(tc->reset_gpio)) {
>> +		ret = PTR_ERR(tc->reset_gpio);
>> +		goto err_clk;
>> +	}
>>   
>>   	if (tc->reset_gpio) {
>>   		gpiod_set_value_cansleep(tc->reset_gpio, 1);
>>   		usleep_range(5000, 10000);
>>   	}
>>   
>> -	tc->refclk = devm_clk_get(dev, "ref");
>> -	if (IS_ERR(tc->refclk)) {
>> -		ret = PTR_ERR(tc->refclk);
>> -		dev_err(dev, "Failed to get refclk: %d\n", ret);
>> -		return ret;
>> -	}
>> -
>>   	tc->regmap = devm_regmap_init_i2c(client, &tc_regmap_config);
>>   	if (IS_ERR(tc->regmap)) {
>>   		ret = PTR_ERR(tc->regmap);
>>   		dev_err(dev, "Failed to initialize regmap: %d\n", ret);
>> -		return ret;
>> +		goto err_clk;
>>   	}
>>   
>>   	ret = of_property_read_u32(dev->of_node, "toshiba,hpd-pin",
>> @@ -2096,7 +2105,7 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
>>   	} else {
>>   		if (tc->hpd_pin < 0 || tc->hpd_pin > 1) {
>>   			dev_err(dev, "failed to parse HPD number\n");
>> -			return ret;
>> +			goto err_clk;
>>   		}
>>   	}
>>   
>> @@ -2110,7 +2119,7 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
>>   						"tc358767-irq", tc);
>>   		if (ret) {
>>   			dev_err(dev, "failed to register dp interrupt\n");
>> -			return ret;
>> +			goto err_clk;
>>   		}
>>   
>>   		tc->have_irq = true;
>> @@ -2119,12 +2128,13 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
>>   	ret = regmap_read(tc->regmap, TC_IDREG, &tc->rev);
>>   	if (ret) {
>>   		dev_err(tc->dev, "can not read device ID: %d\n", ret);
>> -		return ret;
>> +		goto err_clk;
>>   	}
>>   
>>   	if ((tc->rev != 0x6601) && (tc->rev != 0x6603)) {
>>   		dev_err(tc->dev, "invalid device ID: 0x%08x\n", tc->rev);
>> -		return -EINVAL;
>> +		ret = -EINVAL;
>> +		goto err_clk;
>>   	}
>>   
>>   	tc->assr = (tc->rev == 0x6601); /* Enable ASSR for eDP panels */
>> @@ -2164,7 +2174,7 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
>>   	if (tc->bridge.type != DRM_MODE_CONNECTOR_DPI) { /* (e)DP output */
>>   		ret = tc_aux_link_setup(tc);
>>   		if (ret)
>> -			return ret;
>> +			goto err_clk;
>>   	}
>>   
>>   	tc->bridge.of_node = dev->of_node;
>> @@ -2176,11 +2186,15 @@ static int tc_probe(struct i2c_client *client, const struct i2c_device_id *id)
>>   		ret = tc_mipi_dsi_host_attach(tc);
>>   		if (ret) {
>>   			drm_bridge_remove(&tc->bridge);
>> -			return ret;
>> +			goto err_clk;
>>   		}
>>   	}
>>   
>>   	return 0;
>> +
>> +err_clk:
>> +	clk_disable_unprepare(tc->refclk);
>> +	return ret;
> 
> That's a lot of error paths to disable a effectively always-on clock
> when something goes wrong. Could you maybe simplify this by using
> devm_add_action_or_reset for the clock disable? Seems like lots of
> watchdog drivers do this already if you need some inspiration.

I sent V2 as a separate patch.