[PATCH v3] phy: renesas: rcar-gen3-usb2: Fix an error handling path in rcar_gen3_phy_usb2_probe()

Christophe JAILLET posted 1 patch 2 months, 2 weeks ago
There is a newer version of this series
drivers/phy/renesas/phy-rcar-gen3-usb2.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
[PATCH v3] phy: renesas: rcar-gen3-usb2: Fix an error handling path in rcar_gen3_phy_usb2_probe()
Posted by Christophe JAILLET 2 months, 2 weeks ago
If an error occurs after the reset_control_deassert(),
reset_control_assert() must be called, as already done in the remove
function.

Use devm_add_action_or_reset() to add the missing call and simplify the
.remove() function accordingly.

Fixes: 4eae16375357 ("phy: renesas: rcar-gen3-usb2: Add support to initialize the bus")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
This patch changes the order of function calls when releasing the resources
in the .remove function(). Looks fine to me, but pm_ functions are
sometimes tricky.

Changes in v3:
  - Use devm_add_action_or_reset()   [Biju Das]

Changes in v2: (broken proposal)
  - Re-use 'error' to simplify the patch   [claudiu beznea]
  - Update the commit description to explain why it is safe.
v2: https://lore.kernel.org/all/4efe2d0419cbe98163e2422ebe0c7896b8a5efed.1725717505.git.christophe.jaillet@wanadoo.fr/

v1: https://lore.kernel.org/all/fc9f7b444f0ca645411868992bbe16514aeccfed.1725652654.git.christophe.jaillet@wanadoo.fr/
---
 drivers/phy/renesas/phy-rcar-gen3-usb2.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/phy/renesas/phy-rcar-gen3-usb2.c b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
index 58e123305152..c8a3727f56aa 100644
--- a/drivers/phy/renesas/phy-rcar-gen3-usb2.c
+++ b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
@@ -668,6 +668,13 @@ static enum usb_dr_mode rcar_gen3_get_dr_mode(struct device_node *np)
 	return candidate;
 }
 
+static void rcar_gen3_reset_assert(void *data)
+{
+	struct reset_control *rstc = data;
+
+	reset_control_assert(rstc);
+}
+
 static int rcar_gen3_phy_usb2_init_bus(struct rcar_gen3_chan *channel)
 {
 	struct device *dev = channel->dev;
@@ -686,6 +693,11 @@ static int rcar_gen3_phy_usb2_init_bus(struct rcar_gen3_chan *channel)
 	if (ret)
 		goto rpm_put;
 
+	ret = devm_add_action_or_reset(dev, rcar_gen3_reset_assert,
+				       channel->rstc);
+	if (ret)
+		return ret;
+
 	val = readl(channel->base + USB2_AHB_BUS_CTR);
 	val &= ~USB2_AHB_BUS_CTR_MBL_MASK;
 	val |= USB2_AHB_BUS_CTR_MBL_INCR4;
@@ -815,7 +827,6 @@ static void rcar_gen3_phy_usb2_remove(struct platform_device *pdev)
 	if (channel->is_otg_channel)
 		device_remove_file(&pdev->dev, &dev_attr_role);
 
-	reset_control_assert(channel->rstc);
 	pm_runtime_disable(&pdev->dev);
 };
 
-- 
2.46.0
Re: [PATCH v3] phy: renesas: rcar-gen3-usb2: Fix an error handling path in rcar_gen3_phy_usb2_probe()
Posted by Christophe JAILLET 2 months, 2 weeks ago
Le 14/09/2024 à 18:07, Christophe JAILLET a écrit :
> If an error occurs after the reset_control_deassert(),
> reset_control_assert() must be called, as already done in the remove
> function.
> 
> Use devm_add_action_or_reset() to add the missing call and simplify the
> .remove() function accordingly.
> 
> Fixes: 4eae16375357 ("phy: renesas: rcar-gen3-usb2: Add support to initialize the bus")
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> ---
> This patch changes the order of function calls when releasing the resources
> in the .remove function(). Looks fine to me, but pm_ functions are
> sometimes tricky.
> 
> Changes in v3:
>    - Use devm_add_action_or_reset()   [Biju Das]
> 
> Changes in v2: (broken proposal)
>    - Re-use 'error' to simplify the patch   [claudiu beznea]
>    - Update the commit description to explain why it is safe.
> v2: https://lore.kernel.org/all/4efe2d0419cbe98163e2422ebe0c7896b8a5efed.1725717505.git.christophe.jaillet@wanadoo.fr/
> 
> v1: https://lore.kernel.org/all/fc9f7b444f0ca645411868992bbe16514aeccfed.1725652654.git.christophe.jaillet@wanadoo.fr/
> ---
>   drivers/phy/renesas/phy-rcar-gen3-usb2.c | 13 ++++++++++++-
>   1 file changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/phy/renesas/phy-rcar-gen3-usb2.c b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
> index 58e123305152..c8a3727f56aa 100644
> --- a/drivers/phy/renesas/phy-rcar-gen3-usb2.c
> +++ b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
> @@ -668,6 +668,13 @@ static enum usb_dr_mode rcar_gen3_get_dr_mode(struct device_node *np)
>   	return candidate;
>   }
>   
> +static void rcar_gen3_reset_assert(void *data)
> +{
> +	struct reset_control *rstc = data;
> +
> +	reset_control_assert(rstc);
> +}
> +
>   static int rcar_gen3_phy_usb2_init_bus(struct rcar_gen3_chan *channel)
>   {
>   	struct device *dev = channel->dev;
> @@ -686,6 +693,11 @@ static int rcar_gen3_phy_usb2_init_bus(struct rcar_gen3_chan *channel)
>   	if (ret)
>   		goto rpm_put;
>   
> +	ret = devm_add_action_or_reset(dev, rcar_gen3_reset_assert,
> +				       channel->rstc);
> +	if (ret)
> +		return ret;

NACK

This is still broken.
Should be goto rpm_put;

I'll send a v4.

CJ

> +
>   	val = readl(channel->base + USB2_AHB_BUS_CTR);
>   	val &= ~USB2_AHB_BUS_CTR_MBL_MASK;
>   	val |= USB2_AHB_BUS_CTR_MBL_INCR4;
> @@ -815,7 +827,6 @@ static void rcar_gen3_phy_usb2_remove(struct platform_device *pdev)
>   	if (channel->is_otg_channel)
>   		device_remove_file(&pdev->dev, &dev_attr_role);
>   
> -	reset_control_assert(channel->rstc);
>   	pm_runtime_disable(&pdev->dev);
>   };
>