[PATCH 1/1] counter: intel-qep: Use devm_mutex_init()

[PATCH 1/1] counter: intel-qep: Use devm_mutex_init()

[Ilpo Järvinen]

intel_qep_probe() calls mutex_init() but lacks the pairing
mutex_destroy() calls. Convert to devm_mutex_init() which handles
cleanup automatically.

Fixes: b711f687a1c1 ("counter: Add support for Intel Quadrature Encoder Peripheral")
Cc: stable@vger.kernel.org
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
---
 drivers/counter/intel-qep.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/counter/intel-qep.c b/drivers/counter/intel-qep.c
index c49c178056f4..816586893517 100644
--- a/drivers/counter/intel-qep.c
+++ b/drivers/counter/intel-qep.c
@@ -414,7 +414,9 @@ static int intel_qep_probe(struct pci_dev *pci, const struct pci_device_id *id)
 
 	qep->dev = dev;
 	qep->regs = regs;
-	mutex_init(&qep->lock);
+	ret = devm_mutex_init(dev, &qep->lock);
+	if (ret)
+		return ret;
 
 	intel_qep_init(qep);
 	pci_set_drvdata(pci, qep);

base-commit: 1d5dcaa3bd65f2e8c9baa14a393d3a2dc5db7524
-- 
2.47.3

Re: [PATCH 1/1] counter: intel-qep: Use devm_mutex_init()

[Stepan Ionichev]

Reviewed-by: Stepan Ionichev <sozdayvek@gmail.com>

Re: [PATCH 1/1] counter: intel-qep: Use devm_mutex_init()

[Joshua Crofts]

On Wed, 20 May 2026 at 13:25, Ilpo Järvinen
<ilpo.jarvinen@linux.intel.com> wrote:
>
> intel_qep_probe() calls mutex_init() but lacks the pairing
> mutex_destroy() calls. Convert to devm_mutex_init() which handles
> cleanup automatically.
>
> Fixes: b711f687a1c1 ("counter: Add support for Intel Quadrature Encoder Peripheral")
> Cc: stable@vger.kernel.org
> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> ---
>  drivers/counter/intel-qep.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/counter/intel-qep.c b/drivers/counter/intel-qep.c
> index c49c178056f4..816586893517 100644
> --- a/drivers/counter/intel-qep.c
> +++ b/drivers/counter/intel-qep.c
> @@ -414,7 +414,9 @@ static int intel_qep_probe(struct pci_dev *pci, const struct pci_device_id *id)
>
>         qep->dev = dev;
>         qep->regs = regs;
> -       mutex_init(&qep->lock);
> +       ret = devm_mutex_init(dev, &qep->lock);
> +       if (ret)
> +               return ret;

Unless you're compiling with CONFIG_DEBUG_MUTEXES, mutex_destroy() is a
nop, so a solo mutex_init() call is okay. Nevertheless the devm_
counterpart makes
debugging easier.

Reviewed-by: Joshua Crofts <joshua.crofts1@gmail.com>

-- 
Kind regards

CJD

Re: [PATCH 1/1] counter: intel-qep: Use devm_mutex_init()

[William Breathitt Gray]

On Wed, 20 May 2026 14:18:12 +0300, Ilpo Järvinen wrote:
> intel_qep_probe() calls mutex_init() but lacks the pairing
> mutex_destroy() calls. Convert to devm_mutex_init() which handles
> cleanup automatically.
> 
> 

Applied, thanks!

[1/1] counter: intel-qep: Use devm_mutex_init()
      commit: ff35c72101d1dc6793496ade9c1bc3d70dd27bdd

Best regards,
-- 
William Breathitt Gray <wbg@kernel.org>

Re: [PATCH 1/1] counter: intel-qep: Use devm_mutex_init()

[William Breathitt Gray]

On Fri, May 22, 2026 at 10:36:15AM +0900, William Breathitt Gray wrote:
> 
> On Wed, 20 May 2026 14:18:12 +0300, Ilpo Järvinen wrote:
> > intel_qep_probe() calls mutex_init() but lacks the pairing
> > mutex_destroy() calls. Convert to devm_mutex_init() which handles
> > cleanup automatically.
> >
> >
> 
> Applied, thanks!
> 
> [1/1] counter: intel-qep: Use devm_mutex_init()
>       commit: ff35c72101d1dc6793496ade9c1bc3d70dd27bdd
> 
> Best regards,
> --
> William Breathitt Gray <wbg@kernel.org>

Hello Ilpo,

In a similar patch[^1], Jonathan made a good point that a Fixes tag may
not be appropriate for this patch when it only affects debug information
as Joshua pointed out[^2].

So I am going to treat this as an update patch to intel-qep rather than
a bug fix and remove the Fixes tag and stable@vger.kernel.org CC line
from the description. If you feel that this patch really should be
picked up by the stable trees, please let us know and we can discuss
further.

Thank you,

William Breathitt Gray

[^1] https://lore.kernel.org/all/20260527175513.0df47897@jic23-huawei/
[^2] https://lore.kernel.org/all/CALoEA-wrYjbkhM7EiS+f-JjXShpRJw+gqy2zzymq9Ue5t-XN5A@mail.gmail.com/