[PATCH 5/7] media: meson-ir-tx: Ensure clock is disabled on unbind

[PATCH 5/7] media: meson-ir-tx: Ensure clock is disabled on unbind

[Sean Young]

clk_prepare_enabled() needs a call to clk_disable_prepare() on
driver unbind. Make it devm managed.

Fixes: 49be1c78d575 ("media: rc: introduce Meson IR TX driver")
Signed-off-by: Sean Young <sean@mess.org>
---
 drivers/media/rc/meson-ir-tx.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/media/rc/meson-ir-tx.c b/drivers/media/rc/meson-ir-tx.c
index fded2c256f2a..e7bb107e6a84 100644
--- a/drivers/media/rc/meson-ir-tx.c
+++ b/drivers/media/rc/meson-ir-tx.c
@@ -288,8 +288,8 @@ static int meson_irtx_mod_clock_probe(struct meson_irtx *ir,
 	if (!np)
 		return -ENODEV;
 
-	clock = devm_clk_get(ir->dev, "xtal");
-	if (IS_ERR(clock) || clk_prepare_enable(clock))
+	clock = devm_clk_get_enabled(ir->dev, "xtal");
+	if (IS_ERR(clock))
 		return -ENODEV;
 
 	*clk_nr = IRB_MOD_XTAL3_CLK;
-- 
2.55.0


_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic

Re: [PATCH 5/7] media: meson-ir-tx: Ensure clock is disabled on unbind

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 3 potential issue(s) to consider:

New issues:
- [Low] The commit message refers to non-existent clock API functions.

Pre-existing issues:
- [High] The driver masks `-EPROBE_DEFER` and other error codes by unconditionally returning `-ENODEV` when `devm_clk_get_enabled()` or `platform_get_irq()` fails, breaking probe deferral.
- [High] The `rc_dev` structure allocated during probe is permanently leaked on driver unbind due to the use of `rc_allocate_device()` without ensuring a corresponding `rc_free_device()` call.
--

--- Patch [5]: [PATCH 5/7] media: meson-ir-tx: Ensure clock is disabled on unbind ---
commit e95895078113495fea5b981fafe002c5ff1f56c1
Author: Sean Young <sean@mess.org>

media: meson-ir-tx: Ensure clock is disabled on unbind

This patch changes the clock acquisition in the meson-ir-tx driver to use
the devres managed devm_clk_get_enabled(). This ensures the clock is
automatically disabled and unprepared when the driver unbinds.

> clk_prepare_enabled() needs a call to clk_disable_prepare() on
> driver unbind. Make it devm managed.

[Severity: Low]
This isn't a bug, but there are typos in the function names mentioned here.
Should they be clk_prepare_enable() and clk_disable_unprepare() instead?

> diff --git a/drivers/media/rc/meson-ir-tx.c b/drivers/media/rc/meson-ir-tx.c
> index fded2c256f2a6..e7bb107e6a843 100644
> --- a/drivers/media/rc/meson-ir-tx.c
> +++ b/drivers/media/rc/meson-ir-tx.c
> @@ -288,8 +288,8 @@ static int meson_irtx_mod_clock_probe(struct meson_irtx *ir,
>  	if (!np)
>  		return -ENODEV;
>  
> -	clock = devm_clk_get(ir->dev, "xtal");
> -	if (IS_ERR(clock) || clk_prepare_enable(clock))
> +	clock = devm_clk_get_enabled(ir->dev, "xtal");
> +	if (IS_ERR(clock))
>  		return -ENODEV;

[Severity: High]
This is a pre-existing issue, but does this incorrectly mask -EPROBE_DEFER?

If devm_clk_get_enabled() returns -EPROBE_DEFER, returning a hardcoded
-ENODEV will permanently fail the probe instead of allowing it to defer.
Would it be better to return PTR_ERR(clock) here?

The same issue appears to happen with platform_get_irq() in
meson_irtx_probe():

drivers/media/rc/meson-ir-tx.c:meson_irtx_probe() {
    ...
    irq = platform_get_irq(pdev, 0);
    if (irq < 0)
        return -ENODEV;
    ...
}

Would it be better to propagate these error codes directly?


[Severity: High]
This is another pre-existing issue, but does this driver permanently leak
the rc_dev structure on unbind?

The driver allocates the structure manually in meson_irtx_probe():

drivers/media/rc/meson-ir-tx.c:meson_irtx_probe() {
    ...
    rc = rc_allocate_device(RC_DRIVER_IR_RAW_TX);
    ...
    ret = devm_rc_register_device(dev, rc);
    ...
}

Since devm_rc_register_device() only ties rc_unregister_device() to the
devres cleanup, and there is no matching rc_free_device() call or use of
devm_rc_allocate_device(), does the initial reference count remain
un-dropped when the driver is unbound?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/cover.1783673420.git.sean@mess.org?part=5

_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic

Re: [PATCH 5/7] media: meson-ir-tx: Ensure clock is disabled on unbind

[Martin Blumenstingl]

On Fri, Jul 10, 2026 at 10:53 AM Sean Young <sean@mess.org> wrote:
>
> clk_prepare_enabled() needs a call to clk_disable_prepare() on
> driver unbind. Make it devm managed.
>
> Fixes: 49be1c78d575 ("media: rc: introduce Meson IR TX driver")
> Signed-off-by: Sean Young <sean@mess.org>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>

The additional error that sashiko reported will need to be fixed too.
Let's do that in a separate patch though to keep things simple.

_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic

[PATCH 6/7] media: meson-ir-tx: Ensure rc_free_device() is called on unbind

[Sean Young]

Make rc_dev devm managed.

Fixes: dccc0c3ddf8f ("media: rc: fix race between unregister and urb/irq callbacks")
Signed-off-by: Sean Young <sean@mess.org>
---
 drivers/media/rc/meson-ir-tx.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/media/rc/meson-ir-tx.c b/drivers/media/rc/meson-ir-tx.c
index e7bb107e6a84..abb107d19e8c 100644
--- a/drivers/media/rc/meson-ir-tx.c
+++ b/drivers/media/rc/meson-ir-tx.c
@@ -345,7 +345,7 @@ static int meson_irtx_probe(struct platform_device *pdev)
 	if (ret)
 		return dev_err_probe(dev, ret, "irq request failed\n");
 
-	rc = rc_allocate_device(RC_DRIVER_IR_RAW_TX);
+	rc = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW_TX);
 	if (!rc)
 		return -ENOMEM;
 
@@ -358,10 +358,8 @@ static int meson_irtx_probe(struct platform_device *pdev)
 	rc->s_tx_duty_cycle = meson_irtx_set_duty_cycle;
 
 	ret = devm_rc_register_device(dev, rc);
-	if (ret < 0) {
-		rc_free_device(rc);
+	if (ret < 0)
 		return dev_err_probe(dev, ret, "rc_dev registration failed\n");
-	}
 
 	return 0;
 }
-- 
2.55.0


_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic

Re: [PATCH 6/7] media: meson-ir-tx: Ensure rc_free_device() is called on unbind

[Martin Blumenstingl]

On Fri, Jul 10, 2026 at 10:53 AM Sean Young <sean@mess.org> wrote:
>
> Make rc_dev devm managed.
>
> Fixes: dccc0c3ddf8f ("media: rc: fix race between unregister and urb/irq callbacks")
> Signed-off-by: Sean Young <sean@mess.org>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>

_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic