2022-11-09 10:05:52

by Pin-yen Lin

[permalink] [raw]
Subject: [PATCH] drm/bridge: it6505: Guard bridge power in IRQ handler

Add a pair of pm_runtime_get_if_in_use and pm_runtime_put_sync in the
interrupt handler to make sure the bridge won't be powered off during
the interrupt handlings. Also remove the irq_lock mutex because it's not
guarding anything now.

Fixes: ab28896f1a83 ("drm/bridge: it6505: Improve synchronization between extcon subsystem")
Signed-off-by: Pin-yen Lin <[email protected]>
---

drivers/gpu/drm/bridge/ite-it6505.c | 22 ++++++++--------------
1 file changed, 8 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c
index 21a9b8422bda..e7f7d0ce1380 100644
--- a/drivers/gpu/drm/bridge/ite-it6505.c
+++ b/drivers/gpu/drm/bridge/ite-it6505.c
@@ -412,7 +412,6 @@ struct it6505 {
* Mutex protects extcon and interrupt functions from interfering
* each other.
*/
- struct mutex irq_lock;
struct mutex extcon_lock;
struct mutex mode_lock; /* used to bridge_detect */
struct mutex aux_lock; /* used to aux data transfers */
@@ -2494,10 +2493,8 @@ static irqreturn_t it6505_int_threaded_handler(int unused, void *data)
};
int int_status[3], i;

- mutex_lock(&it6505->irq_lock);
-
- if (it6505->enable_drv_hold || !it6505->powered)
- goto unlock;
+ if (it6505->enable_drv_hold || pm_runtime_get_if_in_use(dev) <= 0)
+ return IRQ_HANDLED;

int_status[0] = it6505_read(it6505, INT_STATUS_01);
int_status[1] = it6505_read(it6505, INT_STATUS_02);
@@ -2515,16 +2512,14 @@ static irqreturn_t it6505_int_threaded_handler(int unused, void *data)
if (it6505_test_bit(irq_vec[0].bit, (unsigned int *)int_status))
irq_vec[0].handler(it6505);

- if (!it6505->hpd_state)
- goto unlock;
-
- for (i = 1; i < ARRAY_SIZE(irq_vec); i++) {
- if (it6505_test_bit(irq_vec[i].bit, (unsigned int *)int_status))
- irq_vec[i].handler(it6505);
+ if (it6505->hpd_state) {
+ for (i = 1; i < ARRAY_SIZE(irq_vec); i++) {
+ if (it6505_test_bit(irq_vec[i].bit, (unsigned int *)int_status))
+ irq_vec[i].handler(it6505);
+ }
}

-unlock:
- mutex_unlock(&it6505->irq_lock);
+ pm_runtime_put_sync(dev);

return IRQ_HANDLED;
}
@@ -3277,7 +3272,6 @@ static int it6505_i2c_probe(struct i2c_client *client,
if (!it6505)
return -ENOMEM;

- mutex_init(&it6505->irq_lock);
mutex_init(&it6505->extcon_lock);
mutex_init(&it6505->mode_lock);
mutex_init(&it6505->aux_lock);
--
2.38.1.431.g37b22c650d-goog



2022-12-14 04:01:47

by Pin-yen Lin

[permalink] [raw]
Subject: Re: [PATCH] drm/bridge: it6505: Guard bridge power in IRQ handler

Hi all,

Friendly ping on this patch.

Regards,
Pin-yen

On Wed, Nov 9, 2022 at 5:52 PM Pin-yen Lin <[email protected]> wrote:
>
> Add a pair of pm_runtime_get_if_in_use and pm_runtime_put_sync in the
> interrupt handler to make sure the bridge won't be powered off during
> the interrupt handlings. Also remove the irq_lock mutex because it's not
> guarding anything now.
>
> Fixes: ab28896f1a83 ("drm/bridge: it6505: Improve synchronization between extcon subsystem")
> Signed-off-by: Pin-yen Lin <[email protected]>
> ---
>
> drivers/gpu/drm/bridge/ite-it6505.c | 22 ++++++++--------------
> 1 file changed, 8 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c
> index 21a9b8422bda..e7f7d0ce1380 100644
> --- a/drivers/gpu/drm/bridge/ite-it6505.c
> +++ b/drivers/gpu/drm/bridge/ite-it6505.c
> @@ -412,7 +412,6 @@ struct it6505 {
> * Mutex protects extcon and interrupt functions from interfering
> * each other.
> */
> - struct mutex irq_lock;
> struct mutex extcon_lock;
> struct mutex mode_lock; /* used to bridge_detect */
> struct mutex aux_lock; /* used to aux data transfers */
> @@ -2494,10 +2493,8 @@ static irqreturn_t it6505_int_threaded_handler(int unused, void *data)
> };
> int int_status[3], i;
>
> - mutex_lock(&it6505->irq_lock);
> -
> - if (it6505->enable_drv_hold || !it6505->powered)
> - goto unlock;
> + if (it6505->enable_drv_hold || pm_runtime_get_if_in_use(dev) <= 0)
> + return IRQ_HANDLED;
>
> int_status[0] = it6505_read(it6505, INT_STATUS_01);
> int_status[1] = it6505_read(it6505, INT_STATUS_02);
> @@ -2515,16 +2512,14 @@ static irqreturn_t it6505_int_threaded_handler(int unused, void *data)
> if (it6505_test_bit(irq_vec[0].bit, (unsigned int *)int_status))
> irq_vec[0].handler(it6505);
>
> - if (!it6505->hpd_state)
> - goto unlock;
> -
> - for (i = 1; i < ARRAY_SIZE(irq_vec); i++) {
> - if (it6505_test_bit(irq_vec[i].bit, (unsigned int *)int_status))
> - irq_vec[i].handler(it6505);
> + if (it6505->hpd_state) {
> + for (i = 1; i < ARRAY_SIZE(irq_vec); i++) {
> + if (it6505_test_bit(irq_vec[i].bit, (unsigned int *)int_status))
> + irq_vec[i].handler(it6505);
> + }
> }
>
> -unlock:
> - mutex_unlock(&it6505->irq_lock);
> + pm_runtime_put_sync(dev);
>
> return IRQ_HANDLED;
> }
> @@ -3277,7 +3272,6 @@ static int it6505_i2c_probe(struct i2c_client *client,
> if (!it6505)
> return -ENOMEM;
>
> - mutex_init(&it6505->irq_lock);
> mutex_init(&it6505->extcon_lock);
> mutex_init(&it6505->mode_lock);
> mutex_init(&it6505->aux_lock);
> --
> 2.38.1.431.g37b22c650d-goog
>

2022-12-15 11:23:07

by Robert Foss

[permalink] [raw]
Subject: Re: [PATCH] drm/bridge: it6505: Guard bridge power in IRQ handler

On Wed, 14 Dec 2022 at 04:30, Pin-yen Lin <[email protected]> wrote:
>
> Hi all,
>
> Friendly ping on this patch.
>
> Regards,
> Pin-yen
>
> On Wed, Nov 9, 2022 at 5:52 PM Pin-yen Lin <[email protected]> wrote:
> >
> > Add a pair of pm_runtime_get_if_in_use and pm_runtime_put_sync in the
> > interrupt handler to make sure the bridge won't be powered off during
> > the interrupt handlings. Also remove the irq_lock mutex because it's not
> > guarding anything now.
> >
> > Fixes: ab28896f1a83 ("drm/bridge: it6505: Improve synchronization between extcon subsystem")
> > Signed-off-by: Pin-yen Lin <[email protected]>
> > ---
> >
> > drivers/gpu/drm/bridge/ite-it6505.c | 22 ++++++++--------------
> > 1 file changed, 8 insertions(+), 14 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c
> > index 21a9b8422bda..e7f7d0ce1380 100644
> > --- a/drivers/gpu/drm/bridge/ite-it6505.c
> > +++ b/drivers/gpu/drm/bridge/ite-it6505.c
> > @@ -412,7 +412,6 @@ struct it6505 {
> > * Mutex protects extcon and interrupt functions from interfering
> > * each other.
> > */
> > - struct mutex irq_lock;
> > struct mutex extcon_lock;
> > struct mutex mode_lock; /* used to bridge_detect */
> > struct mutex aux_lock; /* used to aux data transfers */
> > @@ -2494,10 +2493,8 @@ static irqreturn_t it6505_int_threaded_handler(int unused, void *data)
> > };
> > int int_status[3], i;
> >
> > - mutex_lock(&it6505->irq_lock);
> > -
> > - if (it6505->enable_drv_hold || !it6505->powered)
> > - goto unlock;
> > + if (it6505->enable_drv_hold || pm_runtime_get_if_in_use(dev) <= 0)
> > + return IRQ_HANDLED;
> >
> > int_status[0] = it6505_read(it6505, INT_STATUS_01);
> > int_status[1] = it6505_read(it6505, INT_STATUS_02);
> > @@ -2515,16 +2512,14 @@ static irqreturn_t it6505_int_threaded_handler(int unused, void *data)
> > if (it6505_test_bit(irq_vec[0].bit, (unsigned int *)int_status))
> > irq_vec[0].handler(it6505);
> >
> > - if (!it6505->hpd_state)
> > - goto unlock;
> > -
> > - for (i = 1; i < ARRAY_SIZE(irq_vec); i++) {
> > - if (it6505_test_bit(irq_vec[i].bit, (unsigned int *)int_status))
> > - irq_vec[i].handler(it6505);
> > + if (it6505->hpd_state) {
> > + for (i = 1; i < ARRAY_SIZE(irq_vec); i++) {
> > + if (it6505_test_bit(irq_vec[i].bit, (unsigned int *)int_status))
> > + irq_vec[i].handler(it6505);
> > + }
> > }
> >
> > -unlock:
> > - mutex_unlock(&it6505->irq_lock);
> > + pm_runtime_put_sync(dev);
> >
> > return IRQ_HANDLED;
> > }
> > @@ -3277,7 +3272,6 @@ static int it6505_i2c_probe(struct i2c_client *client,
> > if (!it6505)
> > return -ENOMEM;
> >
> > - mutex_init(&it6505->irq_lock);
> > mutex_init(&it6505->extcon_lock);
> > mutex_init(&it6505->mode_lock);
> > mutex_init(&it6505->aux_lock);
> > --
> > 2.38.1.431.g37b22c650d-goog
> >


Applied to drm-misc-next.


Rob.