phy: amlogic: meson8b-usb2: fix shared reset control use

[ Upstream commit 6f1dedf089ab1a4f03ea7aadc3c4a99885b4b4a0 ]

Use reset_control_rearm() call if an error occurs in case
phy_meson8b_usb2_power_on() fails after reset() has been called, or in
case phy_meson8b_usb2_power_off() is called i.e the resource is no longer
used and the reset line may be triggered again by other devices.

reset_control_rearm() keeps use of triggered_count sane in the reset
framework, use of reset_control_reset() on shared reset line should
be balanced with reset_control_rearm().

Signed-off-by: Amjad Ouled-Ameur <aouledameur@baylibre.com>
Reported-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/20220111095255.176141-4-aouledameur@baylibre.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/phy/amlogic/phy-meson8b-usb2.c b/drivers/phy/amlogic/phy-meson8b-usb2.c
index 77e7e9b..dd96763 100644 (file)
--- a/drivers/phy/amlogic/phy-meson8b-usb2.c
+++ b/drivers/phy/amlogic/phy-meson8b-usb2.c
@@ -154,6 +154,7 @@ static int phy_meson8b_usb2_power_on(struct phy *phy)
        ret = clk_prepare_enable(priv->clk_usb_general);
        if (ret) {
                dev_err(&phy->dev, "Failed to enable USB general clock\n");
+               reset_control_rearm(priv->reset);
                return ret;
        }
 
@@ -161,6 +162,7 @@ static int phy_meson8b_usb2_power_on(struct phy *phy)
        if (ret) {
                dev_err(&phy->dev, "Failed to enable USB DDR clock\n");
                clk_disable_unprepare(priv->clk_usb_general);
+               reset_control_rearm(priv->reset);
                return ret;
        }
 
@@ -199,6 +201,7 @@ static int phy_meson8b_usb2_power_on(struct phy *phy)
                                dev_warn(&phy->dev, "USB ID detect failed!\n");
                                clk_disable_unprepare(priv->clk_usb);
                                clk_disable_unprepare(priv->clk_usb_general);
+                               reset_control_rearm(priv->reset);
                                return -EINVAL;
                        }
                }
@@ -218,6 +221,7 @@ static int phy_meson8b_usb2_power_off(struct phy *phy)
 
        clk_disable_unprepare(priv->clk_usb);
        clk_disable_unprepare(priv->clk_usb_general);
+       reset_control_rearm(priv->reset);
 
        /* power off the PHY by putting it into reset mode */
        regmap_update_bits(priv->regmap, REG_CTRL, REG_CTRL_POWER_ON_RESET,