[PATCH v4] phy: renesas: rcar-gen3-usb2: Fix an error handling path in rcar_gen3_phy_usb2_probe()

[Christophe JAILLET]

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@xxxxxxxxxx>
---
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 v4:
  - Use the error handling path in rcar_gen3_phy_usb2_init_bus()

Changes in v3:
  - Use devm_add_action_or_reset()   [Biju Das]
v3: https://lore.kernel.org/all/290b25827e3f0742808940719455ff0c5cb9d01d.1726329925.git.christophe.jaillet@xxxxxxxxxx/

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@xxxxxxxxxx/

v1: https://lore.kernel.org/all/fc9f7b444f0ca645411868992bbe16514aeccfed.1725652654.git.christophe.jaillet@xxxxxxxxxx/
---
 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..f900fe42c311 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)
+		goto rpm_put;
+
 	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