[PATCH v5 0/5] phy: fsl-imx8mq-usb: few improvements

[PATCH v5 0/5] phy: fsl-imx8mq-usb: few improvements

[Xu Yang]

This patchset is a continuous of v2, it mainly resolves some concerns
reported by sashiko-bot.

Patch #1 fix Type-C switch resource leak if probe() fails.
Patch #3 add runtime PM support to avoid register access issue if the
      USB controller enters into runtime suspended state, in this state
      accessing USB PHY register may lack some resources. This will also
      avoid regulator leak if power_on() fails.
Patch #4 add debug control register regmap
Patch #5 correct i.MX8MP USB runtime wakeup issue after introduce runtime
      PM support.

---
Changes in v5:
- not use devm runtime callback to avoid clk enable/disable imblance
- Link to v4: https://patch.msgid.link/20260605-imx8mp-usb-phy-improvement-v4-0-b2ddf2f3862c@nxp.com

Changes in v4:
- add Rb tag
- replace guard() with PM_RUNTIME_ACQUIRE()
- Link to v3: https://patch.msgid.link/20260603-imx8mp-usb-phy-improvement-v3-0-7afb8f89abc6@nxp.com

Link to v2:
 - https://lore.kernel.org/linux-phy/20260512101046.1498096-1-xu.yang_2@nxp.com/
 - https://lore.kernel.org/linux-phy/20260512101212.1498223-1-xu.yang_2@nxp.com/

---
Felix Gu (1):
      phy: fsl-imx8mq-usb: fix typec switch leak on probe error path

Xu Yang (4):
      phy: fsl-imx8mq-usb: set usb phy to be wakeup capable
      phy: fsl-imx8mq-usb: add runtime PM support
      phy: fsl-imx8mq-usb: add control register regmap
      phy: fsl-imx8mq-usb: keep PHY power domain runtime always-on for i.MX8MP

 drivers/phy/freescale/phy-fsl-imx8mq-usb.c | 131 +++++++++++++++++++++--------
 1 file changed, 96 insertions(+), 35 deletions(-)
---
base-commit: 7de6ae9e12207ec146f2f3f1e58d1a99317e88bc
change-id: 20260602-imx8mp-usb-phy-improvement-4272d308d862

Best regards,
--  
Xu Yang <xu.yang_2@nxp.com>

[PATCH v5 1/5] phy: fsl-imx8mq-usb: fix typec switch leak on probe error path

[Xu Yang]

From: Felix Gu <ustc.gu@gmail.com>

If probe fails after imx95_usb_phy_get_tca() succeeds, the typec
switch leaks because the only cleanup path was in .remove, which
never runs on probe failure.

Use devm_add_action_or_reset() so the switch is cleaned up on both
probe failure and driver removal.  The .remove callback and
imx95_usb_phy_put_tca() are no longer needed.

Fixes: b58f0f86fd61 ("phy: fsl-imx8mq-usb: add tca function driver for imx95")
Cc: stable@vger.kernel.org
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Xu Yang <xu.yang_2@nxp.com>
Signed-off-by: Felix Gu <ustc.gu@gmail.com>
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>

---
Changes in v5:
 - keep remove() callback as patch #3 needs it
Changes in v4:
 - add my signed-off tag
Changes in v3:
 - add R-b tag
 - cc statble
 - drop "sw = data" conversion
---
 drivers/phy/freescale/phy-fsl-imx8mq-usb.c | 21 +++++++--------------
 1 file changed, 7 insertions(+), 14 deletions(-)

diff --git a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
index b05d80e849a1..9a33c06d6fc3 100644
--- a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
+++ b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
@@ -173,9 +173,9 @@ static struct typec_switch_dev *tca_blk_get_typec_switch(struct platform_device
 	return sw;
 }
 
-static void tca_blk_put_typec_switch(struct typec_switch_dev *sw)
+static void tca_blk_put_typec_switch(void *data)
 {
-	typec_switch_unregister(sw);
+	typec_switch_unregister(data);
 }
 
 static void tca_blk_orientation_set(struct tca_blk *tca,
@@ -248,6 +248,7 @@ static struct tca_blk *imx95_usb_phy_get_tca(struct platform_device *pdev,
 	struct device *dev = &pdev->dev;
 	struct resource *res;
 	struct tca_blk *tca;
+	int ret;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 	if (!res)
@@ -266,17 +267,11 @@ static struct tca_blk *imx95_usb_phy_get_tca(struct platform_device *pdev,
 	tca->orientation = TYPEC_ORIENTATION_NORMAL;
 	tca->sw = tca_blk_get_typec_switch(pdev, imx_phy);
 
-	return tca;
-}
-
-static void imx95_usb_phy_put_tca(struct imx8mq_usb_phy *imx_phy)
-{
-	struct tca_blk *tca = imx_phy->tca;
-
-	if (!tca)
-		return;
+	ret = devm_add_action_or_reset(&pdev->dev, tca_blk_put_typec_switch, tca->sw);
+	if (ret)
+		return ERR_PTR(ret);
 
-	tca_blk_put_typec_switch(tca->sw);
+	return tca;
 }
 
 static u32 phy_tx_vref_tune_from_property(u32 percent)
@@ -741,9 +736,7 @@ static int imx8mq_usb_phy_probe(struct platform_device *pdev)
 
 static void imx8mq_usb_phy_remove(struct platform_device *pdev)
 {
-	struct imx8mq_usb_phy *imx_phy = platform_get_drvdata(pdev);
 
-	imx95_usb_phy_put_tca(imx_phy);
 }
 
 static struct platform_driver imx8mq_usb_phy_driver = {

-- 
2.34.1

Re: [PATCH v5 1/5] phy: fsl-imx8mq-usb: fix typec switch leak on probe error path

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:

Pre-existing issues:
- [High] Race condition causing NULL pointer dereference during device probe.
- [High] Use-After-Free of devm-allocated driver data during device unbind.
--

commit d64f34cfc15d26f577e5ff3a17572cf971e65696
Author: Felix Gu <ustc.gu@gmail.com>

phy: fsl-imx8mq-usb: fix typec switch leak on probe error path

If probe fails after imx95_usb_phy_get_tca() succeeds, the typec
switch leaks because the only cleanup path was in .remove, which
never runs on probe failure. Use devm_add_action_or_reset() so the
switch is cleaned up on both probe failure and driver removal.

> diff --git a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> --- a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> +++ b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
[ ... ]
> @@ -266,17 +267,11 @@ static struct tca_blk *imx95_usb_phy_get_tca(struct platform_device *pdev,
>  	tca->orientation = TYPEC_ORIENTATION_NORMAL;
>  	tca->sw = tca_blk_get_typec_switch(pdev, imx_phy);

[Severity: High]
This is a pre-existing issue, but does this code introduce a race
condition during probe?

When tca_blk_get_typec_switch() registers the switch, it is immediately
visible to consumers. However, imx_phy->tca has not been assigned yet.
It is only assigned after returning from imx95_usb_phy_get_tca() in
imx8mq_usb_phy_probe().

If a consumer concurrently finds the switch and calls typec_switch_set(),
tca_blk_typec_switch_set() will access imx_phy->tca->orientation,
dereferencing a NULL pointer.

>  
> -	return tca;
> -}
> -
> -static void imx95_usb_phy_put_tca(struct imx8mq_usb_phy *imx_phy)
> -{
> -	struct tca_blk *tca = imx_phy->tca;
> -
> -	if (!tca)
> -		return;
> +	ret = devm_add_action_or_reset(&pdev->dev, tca_blk_put_typec_switch, tca->sw);

[Severity: High]
This is a pre-existing issue, but could this devm cleanup lead to a
use-after-free during driver unbind?

The imx_phy and tca structures are allocated via devm_kzalloc(). During
unbind, this devres action will execute tca_blk_put_typec_switch(), which
calls typec_switch_unregister().

While typec_switch_unregister() unlinks the device, if a consumer still
holds a reference to the switch, the object itself will outlive the driver
unbind. Since devres immediately frees imx_phy and tca after the action
returns, any subsequent call to tca_blk_typec_switch_set() by the active
consumer will access freed memory.

> +	if (ret)
> +		return ERR_PTR(ret);
>  
> -	tca_blk_put_typec_switch(tca->sw);
> +	return tca;
>  }

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260630-imx8mp-usb-phy-improvement-v5-0-25d616403844@nxp.com?part=1

[PATCH v5 2/5] phy: fsl-imx8mq-usb: set usb phy to be wakeup capable

[Xu Yang]

From: Xu Yang <xu.yang_2@nxp.com>

Set PHY wakeup capable because this PHY supports remote wakeup function.

Reviewed-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>

---
Changes in v5:
 - no changes
Changes in v4:
 - add Rb tag
Changes in v3:
 - no changes
Changes in v2:
 - no changes
---
 drivers/phy/freescale/phy-fsl-imx8mq-usb.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
index 9a33c06d6fc3..3a5788c609e1 100644
--- a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
+++ b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
@@ -728,6 +728,7 @@ static int imx8mq_usb_phy_probe(struct platform_device *pdev)
 					"failed to get tca\n");
 
 	imx8m_get_phy_tuning_data(imx_phy);
+	device_set_wakeup_capable(dev, true);
 
 	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
 

-- 
2.34.1

[PATCH v5 3/5] phy: fsl-imx8mq-usb: add runtime PM support

[Xu Yang]

From: Xu Yang <xu.yang_2@nxp.com>

Add runtime PM to ensure the PHY is properly powered and clocked during
register access, preventing potential system hangs.

It guards register access in the following scenarios:
- PHY operations: init() and power_on/off() callbacks are guarded by
  phy core
- Type-C orientation switching when PHY/Controller are suspended which
  needs explicitly care
- Future PHY control port register regmap debugfs access

Signed-off-by: Xu Yang <xu.yang_2@nxp.com>

---
Changes in v5:
 - use non-devm PM runtime callback to correctly enable/disable clocks
   when unbind the device
Changes in v4:
 - replace guard() with PM_RUNTIME_ACQUIRE()
Changes in v3:
 - new patch
---
 drivers/phy/freescale/phy-fsl-imx8mq-usb.c | 64 +++++++++++++++++++++---------
 1 file changed, 45 insertions(+), 19 deletions(-)

diff --git a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
index 3a5788c609e1..9d1dd0e7352e 100644
--- a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
+++ b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
@@ -9,6 +9,7 @@
 #include <linux/of.h>
 #include <linux/phy/phy.h>
 #include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
 #include <linux/regulator/consumer.h>
 #include <linux/usb/typec_mux.h>
 
@@ -136,17 +137,15 @@ static int tca_blk_typec_switch_set(struct typec_switch_dev *sw,
 {
 	struct imx8mq_usb_phy *imx_phy = typec_switch_get_drvdata(sw);
 	struct tca_blk *tca = imx_phy->tca;
-	int ret;
 
 	if (tca->orientation == orientation)
 		return 0;
 
-	ret = clk_prepare_enable(imx_phy->clk);
-	if (ret)
-		return ret;
+	PM_RUNTIME_ACQUIRE(&imx_phy->phy->dev, pm);
+	if (PM_RUNTIME_ACQUIRE_ERR(&pm))
+		return -ENXIO;
 
 	tca_blk_orientation_set(tca, orientation);
-	clk_disable_unprepare(imx_phy->clk);
 
 	return 0;
 }
@@ -620,16 +619,6 @@ static int imx8mq_phy_power_on(struct phy *phy)
 	if (ret)
 		return ret;
 
-	ret = clk_prepare_enable(imx_phy->clk);
-	if (ret)
-		return ret;
-
-	ret = clk_prepare_enable(imx_phy->alt_clk);
-	if (ret) {
-		clk_disable_unprepare(imx_phy->clk);
-		return ret;
-	}
-
 	/* Disable rx term override */
 	value = readl(imx_phy->base + PHY_CTRL6);
 	value &= ~PHY_CTRL6_RXTERM_OVERRIDE_SEL;
@@ -648,8 +637,6 @@ static int imx8mq_phy_power_off(struct phy *phy)
 	value |= PHY_CTRL6_RXTERM_OVERRIDE_SEL;
 	writel(value, imx_phy->base + PHY_CTRL6);
 
-	clk_disable_unprepare(imx_phy->alt_clk);
-	clk_disable_unprepare(imx_phy->clk);
 	regulator_disable(imx_phy->vbus);
 
 	return 0;
@@ -693,13 +680,13 @@ static int imx8mq_usb_phy_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, imx_phy);
 
-	imx_phy->clk = devm_clk_get(dev, "phy");
+	imx_phy->clk = devm_clk_get_enabled(dev, "phy");
 	if (IS_ERR(imx_phy->clk)) {
 		dev_err(dev, "failed to get imx8mq usb phy clock\n");
 		return PTR_ERR(imx_phy->clk);
 	}
 
-	imx_phy->alt_clk = devm_clk_get_optional(dev, "alt");
+	imx_phy->alt_clk = devm_clk_get_optional_enabled(dev, "alt");
 	if (IS_ERR(imx_phy->alt_clk))
 		return dev_err_probe(dev, PTR_ERR(imx_phy->alt_clk),
 				    "Failed to get alt clk\n");
@@ -708,6 +695,9 @@ static int imx8mq_usb_phy_probe(struct platform_device *pdev)
 	if (IS_ERR(imx_phy->base))
 		return PTR_ERR(imx_phy->base);
 
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+
 	phy_ops = of_device_get_match_data(dev);
 	if (!phy_ops)
 		return -EINVAL;
@@ -737,15 +727,51 @@ static int imx8mq_usb_phy_probe(struct platform_device *pdev)
 
 static void imx8mq_usb_phy_remove(struct platform_device *pdev)
 {
+	struct device *dev = &pdev->dev;
+
+	pm_runtime_get_sync(dev);
+	pm_runtime_disable(dev);
+	pm_runtime_put_noidle(dev);
+}
+
+static int imx8mq_usb_phy_runtime_suspend(struct device *dev)
+{
+	struct imx8mq_usb_phy *imx_phy = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(imx_phy->alt_clk);
+	clk_disable_unprepare(imx_phy->clk);
+
+	return 0;
+}
+
+static int imx8mq_usb_phy_runtime_resume(struct device *dev)
+{
+	struct imx8mq_usb_phy *imx_phy = dev_get_drvdata(dev);
+	int ret;
+
+	ret = clk_prepare_enable(imx_phy->clk);
+	if (ret)
+		return ret;
 
+	ret = clk_prepare_enable(imx_phy->alt_clk);
+	if (ret) {
+		clk_disable_unprepare(imx_phy->clk);
+		return ret;
+	}
+
+	return 0;
 }
 
+static DEFINE_RUNTIME_DEV_PM_OPS(imx8mq_usb_phy_pm_ops, imx8mq_usb_phy_runtime_suspend,
+				 imx8mq_usb_phy_runtime_resume, NULL);
+
 static struct platform_driver imx8mq_usb_phy_driver = {
 	.probe	= imx8mq_usb_phy_probe,
 	.remove = imx8mq_usb_phy_remove,
 	.driver = {
 		.name	= "imx8mq-usb-phy",
 		.of_match_table	= imx8mq_usb_phy_of_match,
+		.pm = pm_ptr(&imx8mq_usb_phy_pm_ops),
 		.suppress_bind_attrs = true,
 	}
 };

-- 
2.34.1

Re: [PATCH v5 3/5] phy: fsl-imx8mq-usb: add runtime PM support

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] Missing `pm_runtime_disable()` in `imx8mq_usb_phy_probe()` error paths causes a `disable_depth` imbalance and PM state corruption.
--

commit e9418c8d510e8492ef9a52ace4cb6d672041d448
Author: Xu Yang <xu.yang_2@nxp.com>

phy: fsl-imx8mq-usb: add runtime PM support

This commit adds runtime PM support to ensure the PHY is properly powered
and clocked during register access, preventing potential system hangs.

> diff --git a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> --- a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> +++ b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c

[ ... ]

> @@ -708,6 +695,9 @@ static int imx8mq_usb_phy_probe(struct platform_device *pdev)
>  	if (IS_ERR(imx_phy->base))
>  		return PTR_ERR(imx_phy->base);
>  
> +	pm_runtime_set_active(dev);
> +	pm_runtime_enable(dev);
> +
>  	phy_ops = of_device_get_match_data(dev);
>  	if (!phy_ops)
>  		return -EINVAL;

[Severity: High]
Does this code need a cleanup path to call pm_runtime_disable() on probe
failures?

If functions following pm_runtime_enable() fail (such as
of_device_get_match_data(), devm_phy_create(), or devm_regulator_get()),
the driver returns the error directly without cleaning up the PM state.

This can leave the disable_depth counter out of sync. If the device probe
defers (for example, if devm_regulator_get() returns -EPROBE_DEFER) and
runs again, the subsequent pm_runtime_enable() could drop the counter
below zero. This might trigger an unbalanced pm_runtime_enable warning
and leave the device permanently stuck in RPM_ACTIVE.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260630-imx8mp-usb-phy-improvement-v5-0-25d616403844@nxp.com?part=3

Re: [PATCH v5 3/5] phy: fsl-imx8mq-usb: add runtime PM support

[Frank Li]

On Tue, Jun 30, 2026 at 06:11:30PM +0800, Xu Yang wrote:
> From: Xu Yang <xu.yang_2@nxp.com>
>
> Add runtime PM to ensure the PHY is properly powered and clocked during
> register access, preventing potential system hangs.
>
> It guards register access in the following scenarios:
> - PHY operations: init() and power_on/off() callbacks are guarded by
>   phy core
> - Type-C orientation switching when PHY/Controller are suspended which
>   needs explicitly care
> - Future PHY control port register regmap debugfs access
>
> Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
>
> ---
> Changes in v5:
>  - use non-devm PM runtime callback to correctly enable/disable clocks
>    when unbind the device
> Changes in v4:
>  - replace guard() with PM_RUNTIME_ACQUIRE()
> Changes in v3:
>  - new patch
> ---
>  drivers/phy/freescale/phy-fsl-imx8mq-usb.c | 64 +++++++++++++++++++++---------
>  1 file changed, 45 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> index 3a5788c609e1..9d1dd0e7352e 100644
> --- a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> +++ b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> @@ -9,6 +9,7 @@
>  #include <linux/of.h>
>  #include <linux/phy/phy.h>
>  #include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
>  #include <linux/regulator/consumer.h>
>  #include <linux/usb/typec_mux.h>
>
> @@ -136,17 +137,15 @@ static int tca_blk_typec_switch_set(struct typec_switch_dev *sw,
>  {
>  	struct imx8mq_usb_phy *imx_phy = typec_switch_get_drvdata(sw);
>  	struct tca_blk *tca = imx_phy->tca;
> -	int ret;
>
>  	if (tca->orientation == orientation)
>  		return 0;
>
> -	ret = clk_prepare_enable(imx_phy->clk);
> -	if (ret)
> -		return ret;
> +	PM_RUNTIME_ACQUIRE(&imx_phy->phy->dev, pm);
> +	if (PM_RUNTIME_ACQUIRE_ERR(&pm))
> +		return -ENXIO;
>
>  	tca_blk_orientation_set(tca, orientation);
> -	clk_disable_unprepare(imx_phy->clk);
>
>  	return 0;
>  }
> @@ -620,16 +619,6 @@ static int imx8mq_phy_power_on(struct phy *phy)
>  	if (ret)
>  		return ret;
>
> -	ret = clk_prepare_enable(imx_phy->clk);
> -	if (ret)
> -		return ret;
> -
> -	ret = clk_prepare_enable(imx_phy->alt_clk);
> -	if (ret) {
> -		clk_disable_unprepare(imx_phy->clk);
> -		return ret;
> -	}
> -
>  	/* Disable rx term override */
>  	value = readl(imx_phy->base + PHY_CTRL6);
>  	value &= ~PHY_CTRL6_RXTERM_OVERRIDE_SEL;
> @@ -648,8 +637,6 @@ static int imx8mq_phy_power_off(struct phy *phy)
>  	value |= PHY_CTRL6_RXTERM_OVERRIDE_SEL;
>  	writel(value, imx_phy->base + PHY_CTRL6);
>
> -	clk_disable_unprepare(imx_phy->alt_clk);
> -	clk_disable_unprepare(imx_phy->clk);
>  	regulator_disable(imx_phy->vbus);
>
>  	return 0;
> @@ -693,13 +680,13 @@ static int imx8mq_usb_phy_probe(struct platform_device *pdev)
>
>  	platform_set_drvdata(pdev, imx_phy);
>
> -	imx_phy->clk = devm_clk_get(dev, "phy");
> +	imx_phy->clk = devm_clk_get_enabled(dev, "phy");
>  	if (IS_ERR(imx_phy->clk)) {
>  		dev_err(dev, "failed to get imx8mq usb phy clock\n");
>  		return PTR_ERR(imx_phy->clk);
>  	}
>
> -	imx_phy->alt_clk = devm_clk_get_optional(dev, "alt");
> +	imx_phy->alt_clk = devm_clk_get_optional_enabled(dev, "alt");
>  	if (IS_ERR(imx_phy->alt_clk))
>  		return dev_err_probe(dev, PTR_ERR(imx_phy->alt_clk),
>  				    "Failed to get alt clk\n");
> @@ -708,6 +695,9 @@ static int imx8mq_usb_phy_probe(struct platform_device *pdev)
>  	if (IS_ERR(imx_phy->base))
>  		return PTR_ERR(imx_phy->base);
>
> +	pm_runtime_set_active(dev);
> +	pm_runtime_enable(dev);
> +

devm_pm_runtime_enable();

runtime pm will be always on active status, why suspend it?

>  	phy_ops = of_device_get_match_data(dev);
>  	if (!phy_ops)
>  		return -EINVAL;
> @@ -737,15 +727,51 @@ static int imx8mq_usb_phy_probe(struct platform_device *pdev)
>
>  static void imx8mq_usb_phy_remove(struct platform_device *pdev)
>  {
> +	struct device *dev = &pdev->dev;
> +
> +	pm_runtime_get_sync(dev);
> +	pm_runtime_disable(dev);
> +	pm_runtime_put_noidle(dev);
> +}
> +
> +static int imx8mq_usb_phy_runtime_suspend(struct device *dev)
> +{
> +	struct imx8mq_usb_phy *imx_phy = dev_get_drvdata(dev);
> +
> +	clk_disable_unprepare(imx_phy->alt_clk);
> +	clk_disable_unprepare(imx_phy->clk);

can you switch to use bulk clk api.

Frank
> +
> +	return 0;
> +}
> +
> +static int imx8mq_usb_phy_runtime_resume(struct device *dev)
> +{
> +	struct imx8mq_usb_phy *imx_phy = dev_get_drvdata(dev);
> +	int ret;
> +
> +	ret = clk_prepare_enable(imx_phy->clk);
> +	if (ret)
> +		return ret;
>
> +	ret = clk_prepare_enable(imx_phy->alt_clk);
> +	if (ret) {
> +		clk_disable_unprepare(imx_phy->clk);
> +		return ret;
> +	}
> +
> +	return 0;
>  }
>
> +static DEFINE_RUNTIME_DEV_PM_OPS(imx8mq_usb_phy_pm_ops, imx8mq_usb_phy_runtime_suspend,
> +				 imx8mq_usb_phy_runtime_resume, NULL);
> +
>  static struct platform_driver imx8mq_usb_phy_driver = {
>  	.probe	= imx8mq_usb_phy_probe,
>  	.remove = imx8mq_usb_phy_remove,
>  	.driver = {
>  		.name	= "imx8mq-usb-phy",
>  		.of_match_table	= imx8mq_usb_phy_of_match,
> +		.pm = pm_ptr(&imx8mq_usb_phy_pm_ops),
>  		.suppress_bind_attrs = true,
>  	}
>  };
>
> --
> 2.34.1
>
>

[PATCH v5 4/5] phy: fsl-imx8mq-usb: add control register regmap

[Xu Yang]

From: Xu Yang <xu.yang_2@nxp.com>

The CR port is a simple 16-bit data/address parallel port that is
accessed through 32-bit MMIO registers for on-chip access to the
control registers inside the USB 3.0 femtoPHY. Add control register
regmap and export these registers by debugfs to help PHY's diagnostic.

Reviewed-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>

---
Changes in v5:
 - add Rb tag
Changes in v4:
 - improve commit message as Haibo's suggestion
Changes in v3:
 - drop Frank's tag because it includes other changes
 - new patch
---
 drivers/phy/freescale/phy-fsl-imx8mq-usb.c | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
index 9d1dd0e7352e..4949ec78d304 100644
--- a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
+++ b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0+
-/* Copyright (c) 2017 NXP. */
+/* Copyright 2017-2026 NXP. */
 
 #include <linux/bitfield.h>
 #include <linux/clk.h>
@@ -11,6 +11,7 @@
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/regulator/consumer.h>
+#include <linux/regmap.h>
 #include <linux/usb/typec_mux.h>
 
 #define PHY_CTRL0			0x0
@@ -56,6 +57,8 @@
 #define PHY_CTRL6_ALT_CLK_EN		BIT(1)
 #define PHY_CTRL6_ALT_CLK_SEL		BIT(0)
 
+#define PHY_CRCTL			0x30
+
 #define PHY_TUNE_DEFAULT		0xffffffff
 
 #define TCA_CLK_RST			0x00
@@ -119,6 +122,7 @@ struct imx8mq_usb_phy {
 	void __iomem *base;
 	struct regulator *vbus;
 	struct tca_blk *tca;
+	struct regmap *cr_regmap;
 	u32 pcs_tx_swing_full;
 	u32 pcs_tx_deemph_3p5db;
 	u32 tx_vref_tune;
@@ -667,6 +671,14 @@ static const struct of_device_id imx8mq_usb_phy_of_match[] = {
 };
 MODULE_DEVICE_TABLE(of, imx8mq_usb_phy_of_match);
 
+static const struct regmap_config imx_cr_regmap_config = {
+	.name = "cr",
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.max_register = 0x7,
+};
+
 static int imx8mq_usb_phy_probe(struct platform_device *pdev)
 {
 	struct phy_provider *phy_provider;
@@ -695,6 +707,13 @@ static int imx8mq_usb_phy_probe(struct platform_device *pdev)
 	if (IS_ERR(imx_phy->base))
 		return PTR_ERR(imx_phy->base);
 
+	imx_phy->cr_regmap = devm_regmap_init_mmio(dev, imx_phy->base + PHY_CRCTL,
+						   &imx_cr_regmap_config);
+	if (IS_ERR(imx_phy->cr_regmap)) {
+		dev_warn(dev, "Fail to init debug register regmap\n");
+		imx_phy->cr_regmap = NULL;
+	}
+
 	pm_runtime_set_active(dev);
 	pm_runtime_enable(dev);
 
@@ -738,6 +757,9 @@ static int imx8mq_usb_phy_runtime_suspend(struct device *dev)
 {
 	struct imx8mq_usb_phy *imx_phy = dev_get_drvdata(dev);
 
+	if (imx_phy->cr_regmap)
+		regcache_cache_only(imx_phy->cr_regmap, true);
+
 	clk_disable_unprepare(imx_phy->alt_clk);
 	clk_disable_unprepare(imx_phy->clk);
 
@@ -759,6 +781,9 @@ static int imx8mq_usb_phy_runtime_resume(struct device *dev)
 		return ret;
 	}
 
+	if (imx_phy->cr_regmap)
+		regcache_cache_only(imx_phy->cr_regmap, false);
+
 	return 0;
 }
 

-- 
2.34.1

Re: [PATCH v5 4/5] phy: fsl-imx8mq-usb: add control register regmap

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Runtime PM enablement is leaked on probe error paths.
--

commit 487a0a8551844cc9b5c38e7f8d7cbf2ec3f1435d
Author: Xu Yang <xu.yang_2@nxp.com>

phy: fsl-imx8mq-usb: add control register regmap

This commit adds a control register regmap for the USB 3.0 femtoPHY.
It exposes these registers through debugfs to assist with diagnostic
efforts.

> diff --git a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> index 9d1dd0e7352ed..4949ec78d3044 100644
> --- a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> +++ b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
[ ... ]
> @@ -695,6 +707,13 @@ static int imx8mq_usb_phy_probe(struct platform_device *pdev)
>  	if (IS_ERR(imx_phy->base))
>  		return PTR_ERR(imx_phy->base);
>  
> +	imx_phy->cr_regmap = devm_regmap_init_mmio(dev, imx_phy->base + PHY_CRCTL,
> +						   &imx_cr_regmap_config);
> +	if (IS_ERR(imx_phy->cr_regmap)) {
> +		dev_warn(dev, "Fail to init debug register regmap\n");
> +		imx_phy->cr_regmap = NULL;
> +	}
> +
>  	pm_runtime_set_active(dev);
>  	pm_runtime_enable(dev);

[Severity: Medium]
Is there a leak of the runtime PM enablement state on probe error paths here?

In imx8mq_usb_phy_probe(), pm_runtime_enable() is called, but subsequent
initialization steps (like devm_phy_create() or devm_regulator_get()) can fail
and return directly without calling pm_runtime_disable().

Could this leave the disable_depth counter at 0 on a probe failure like
-EPROBE_DEFER, resulting in an 'Unbalanced pm_runtime_enable!' warning on the
next probe attempt? Would using devm_pm_runtime_enable() ensure this state is
properly cleaned up?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260630-imx8mp-usb-phy-improvement-v5-0-25d616403844@nxp.com?part=4

[PATCH v5 5/5] phy: fsl-imx8mq-usb: keep PHY power domain runtime always-on for i.MX8MP

[Xu Yang]

From: Xu Yang <xu.yang_2@nxp.com>

On i.MX8MP, the USB PHY has a dedicated power domain that was previously
never powered off at runtime. With the introduction of runtime PM support,
the power domain will be powered off if the device is runtime suspended,
which breaks USB wakeup functionality.

To preserve wakeup functionality, mark the PHY power domain as runtime
always-on for i.MX8MP platform. To limit the behavior to i.MX8MP, add a
new imx95_usb_phy_ops for i.MX95 and introduce usb_phy_is_imx8mp() helper
to identify i.MX8MP PHY instance.

Signed-off-by: Xu Yang <xu.yang_2@nxp.com>

---
Changes in v5:
 - no changes
Changes in v4:
 - no changes
Changes in v3:
 - new patch
---
 drivers/phy/freescale/phy-fsl-imx8mq-usb.c | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
index 4949ec78d304..c9741b532663 100644
--- a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
+++ b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
@@ -9,6 +9,7 @@
 #include <linux/of.h>
 #include <linux/phy/phy.h>
 #include <linux/platform_device.h>
+#include <linux/pm_domain.h>
 #include <linux/pm_runtime.h>
 #include <linux/regulator/consumer.h>
 #include <linux/regmap.h>
@@ -660,13 +661,20 @@ static const struct phy_ops imx8mp_usb_phy_ops = {
 	.owner		= THIS_MODULE,
 };
 
+static const struct phy_ops imx95_usb_phy_ops = {
+	.init		= imx8mp_usb_phy_init,
+	.power_on	= imx8mq_phy_power_on,
+	.power_off	= imx8mq_phy_power_off,
+	.owner		= THIS_MODULE,
+};
+
 static const struct of_device_id imx8mq_usb_phy_of_match[] = {
 	{.compatible = "fsl,imx8mq-usb-phy",
 	 .data = &imx8mq_usb_phy_ops,},
 	{.compatible = "fsl,imx8mp-usb-phy",
 	 .data = &imx8mp_usb_phy_ops,},
 	{.compatible = "fsl,imx95-usb-phy",
-	 .data = &imx8mp_usb_phy_ops,},
+	 .data = &imx95_usb_phy_ops,},
 	{ }
 };
 MODULE_DEVICE_TABLE(of, imx8mq_usb_phy_of_match);
@@ -679,6 +687,11 @@ static const struct regmap_config imx_cr_regmap_config = {
 	.max_register = 0x7,
 };
 
+static bool usb_phy_is_imx8mp(const void *data)
+{
+	return data == &imx8mp_usb_phy_ops;
+}
+
 static int imx8mq_usb_phy_probe(struct platform_device *pdev)
 {
 	struct phy_provider *phy_provider;
@@ -721,6 +734,9 @@ static int imx8mq_usb_phy_probe(struct platform_device *pdev)
 	if (!phy_ops)
 		return -EINVAL;
 
+	if (usb_phy_is_imx8mp(phy_ops))
+		dev_pm_genpd_rpm_always_on(dev, true);
+
 	imx_phy->phy = devm_phy_create(dev, NULL, phy_ops);
 	if (IS_ERR(imx_phy->phy))
 		return PTR_ERR(imx_phy->phy);

-- 
2.34.1

Re: [PATCH v5 5/5] phy: fsl-imx8mq-usb: keep PHY power domain runtime always-on for i.MX8MP

[Frank Li]

On Tue, Jun 30, 2026 at 06:11:32PM +0800, Xu Yang wrote:
> From: Xu Yang <xu.yang_2@nxp.com>
>
> On i.MX8MP, the USB PHY has a dedicated power domain that was previously
> never powered off at runtime. With the introduction of runtime PM support,
> the power domain will be powered off if the device is runtime suspended,
> which breaks USB wakeup functionality.
>
> To preserve wakeup functionality, mark the PHY power domain as runtime
> always-on for i.MX8MP platform. To limit the behavior to i.MX8MP, add a
> new imx95_usb_phy_ops for i.MX95 and introduce usb_phy_is_imx8mp() helper
> to identify i.MX8MP PHY instance.
>
> Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
>
> ---
> Changes in v5:
>  - no changes
> Changes in v4:
>  - no changes
> Changes in v3:
>  - new patch
> ---
>  drivers/phy/freescale/phy-fsl-imx8mq-usb.c | 18 +++++++++++++++++-
>  1 file changed, 17 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> index 4949ec78d304..c9741b532663 100644
> --- a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> +++ b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> @@ -9,6 +9,7 @@
>  #include <linux/of.h>
>  #include <linux/phy/phy.h>
>  #include <linux/platform_device.h>
> +#include <linux/pm_domain.h>
>  #include <linux/pm_runtime.h>
>  #include <linux/regulator/consumer.h>
>  #include <linux/regmap.h>
> @@ -660,13 +661,20 @@ static const struct phy_ops imx8mp_usb_phy_ops = {
>  	.owner		= THIS_MODULE,
>  };
>
> +static const struct phy_ops imx95_usb_phy_ops = {
> +	.init		= imx8mp_usb_phy_init,
> +	.power_on	= imx8mq_phy_power_on,
> +	.power_off	= imx8mq_phy_power_off,
> +	.owner		= THIS_MODULE,
> +};
> +
>  static const struct of_device_id imx8mq_usb_phy_of_match[] = {
>  	{.compatible = "fsl,imx8mq-usb-phy",
>  	 .data = &imx8mq_usb_phy_ops,},
>  	{.compatible = "fsl,imx8mp-usb-phy",
>  	 .data = &imx8mp_usb_phy_ops,},
>  	{.compatible = "fsl,imx95-usb-phy",
> -	 .data = &imx8mp_usb_phy_ops,},
> +	 .data = &imx95_usb_phy_ops,},
>  	{ }
>  };
>  MODULE_DEVICE_TABLE(of, imx8mq_usb_phy_of_match);
> @@ -679,6 +687,11 @@ static const struct regmap_config imx_cr_regmap_config = {
>  	.max_register = 0x7,
>  };
>
> +static bool usb_phy_is_imx8mp(const void *data)
> +{
> +	return data == &imx8mp_usb_phy_ops;
> +}
> +

It is not good direct use drvdata as it.

Can you add new drvdata

drvdata
{
	phy_ops ops;
	bool always_on;
}

in follow probe check

if (always_on)
	...

it is more extendable in future.

Frank
>  static int imx8mq_usb_phy_probe(struct platform_device *pdev)
>  {
>  	struct phy_provider *phy_provider;
> @@ -721,6 +734,9 @@ static int imx8mq_usb_phy_probe(struct platform_device *pdev)
>  	if (!phy_ops)
>  		return -EINVAL;
>
> +	if (usb_phy_is_imx8mp(phy_ops))
> +		dev_pm_genpd_rpm_always_on(dev, true);
> +
>  	imx_phy->phy = devm_phy_create(dev, NULL, phy_ops);
>  	if (IS_ERR(imx_phy->phy))
>  		return PTR_ERR(imx_phy->phy);
>
> --
> 2.34.1
>
>