[PATCH v6 0/3] phy: amlogic: fix shared reset control use

[PATCH v6 0/3] phy: amlogic: fix shared reset control use

[Amjad Ouled-Ameur]

This patchset fixes a usb suspend warning seen on the libretech-cc by
using reset_control_rearm() call of the reset framework API. 
This call allows a reset consummer to release the reset line even when 
just triggered so that it may be triggered again by other reset
consummers.

reset_control_(de)assert() calls are called, in some meson usb drivers, 
on a shared reset line when reset_control_reset has been used. This is not
allowed by the reset framework.

Finally the meson usb drivers are updated to use this new call, which
solves the suspend issue addressed by the previous reverted 
commit 7a410953d1fb ("usb: dwc3: meson-g12a: fix shared reset control
use").

changes since v5:
- No changes.

Amjad Ouled-Ameur (3):
  phy: amlogic: phy-meson-gxl-usb2: fix shared reset controller use
  phy: amlogic: meson8b-usb2: Use dev_err_probe()
  phy: amlogic: meson8b-usb2: fix shared reset control use

 drivers/phy/amlogic/phy-meson-gxl-usb2.c | 5 ++++-
 drivers/phy/amlogic/phy-meson8b-usb2.c   | 9 +++++++--
 2 files changed, 11 insertions(+), 3 deletions(-)

-- 
2.25.1

[PATCH v6 1/3] phy: amlogic: phy-meson-gxl-usb2: fix shared reset controller use

[Amjad Ouled-Ameur]

Use reset_control_rearm() call if an error occurs in case
phy_meson_gxl_usb2_init() fails after reset() has been called ; or in case
phy_meson_gxl_usb2_exit() 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. Therefore, 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>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
---
 drivers/phy/amlogic/phy-meson-gxl-usb2.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/phy/amlogic/phy-meson-gxl-usb2.c b/drivers/phy/amlogic/phy-meson-gxl-usb2.c
index 2b3c0d730f20..db17c3448bfe 100644
--- a/drivers/phy/amlogic/phy-meson-gxl-usb2.c
+++ b/drivers/phy/amlogic/phy-meson-gxl-usb2.c
@@ -114,8 +114,10 @@ static int phy_meson_gxl_usb2_init(struct phy *phy)
 		return ret;
 
 	ret = clk_prepare_enable(priv->clk);
-	if (ret)
+	if (ret) {
+		reset_control_rearm(priv->reset);
 		return ret;
+	}
 
 	return 0;
 }
@@ -125,6 +127,7 @@ static int phy_meson_gxl_usb2_exit(struct phy *phy)
 	struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
 
 	clk_disable_unprepare(priv->clk);
+	reset_control_rearm(priv->reset);
 
 	return 0;
 }
-- 
2.25.1

[PATCH v6 2/3] phy: amlogic: meson8b-usb2: Use dev_err_probe()

[Amjad Ouled-Ameur]

Use the existing dev_err_probe() helper instead of open-coding the same
operation.

Signed-off-by: Amjad Ouled-Ameur <aouledameur@baylibre.com>
Reported-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
---
 drivers/phy/amlogic/phy-meson8b-usb2.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/phy/amlogic/phy-meson8b-usb2.c b/drivers/phy/amlogic/phy-meson8b-usb2.c
index cf10bed40528..77e7e9b1428c 100644
--- a/drivers/phy/amlogic/phy-meson8b-usb2.c
+++ b/drivers/phy/amlogic/phy-meson8b-usb2.c
@@ -265,8 +265,9 @@ static int phy_meson8b_usb2_probe(struct platform_device *pdev)
 		return PTR_ERR(priv->clk_usb);
 
 	priv->reset = devm_reset_control_get_optional_shared(&pdev->dev, NULL);
-	if (PTR_ERR(priv->reset) == -EPROBE_DEFER)
-		return PTR_ERR(priv->reset);
+	if (IS_ERR(priv->reset))
+		return dev_err_probe(&pdev->dev, PTR_ERR(priv->reset),
+				     "Failed to get the reset line");
 
 	priv->dr_mode = of_usb_get_dr_mode_by_phy(pdev->dev.of_node, -1);
 	if (priv->dr_mode == USB_DR_MODE_UNKNOWN) {
-- 
2.25.1

[PATCH v6 3/3] phy: amlogic: meson8b-usb2: fix shared reset control use

[Amjad Ouled-Ameur]

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>
---
 drivers/phy/amlogic/phy-meson8b-usb2.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/phy/amlogic/phy-meson8b-usb2.c b/drivers/phy/amlogic/phy-meson8b-usb2.c
index 77e7e9b1428c..dd96763911b8 100644
--- 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,
-- 
2.25.1

Re: [PATCH v6 0/3] phy: amlogic: fix shared reset control use

[Vinod Koul]

On 11-01-22, 10:52, Amjad Ouled-Ameur wrote:
> This patchset fixes a usb suspend warning seen on the libretech-cc by
> using reset_control_rearm() call of the reset framework API. 
> This call allows a reset consummer to release the reset line even when 
> just triggered so that it may be triggered again by other reset
> consummers.
> 
> reset_control_(de)assert() calls are called, in some meson usb drivers, 
> on a shared reset line when reset_control_reset has been used. This is not
> allowed by the reset framework.
> 
> Finally the meson usb drivers are updated to use this new call, which
> solves the suspend issue addressed by the previous reverted 
> commit 7a410953d1fb ("usb: dwc3: meson-g12a: fix shared reset control
> use").

Applied, thanks

-- 
~Vinod