2024-03-28 16:56:36

by Javier Carrasco

[permalink] [raw]
Subject: [PATCH RESEND 1/2] usb: typec: tipd: fix event checking for tps25750

In its current form, the interrupt service routine of the tps25750
checks the event flags in the lowest 64 bits of the interrupt event
register (event[0]), but also in the upper part (event[1]).

Given that all flags are defined as BIT() or BIT_ULL(), they are
restricted to the first 64 bits of the INT_EVENT1 register. Including
the upper part of the register can lead to false positives e.g. if the
event 64 bits above the one being checked is set, but the one being
checked is not.

Restrict the flag checking to the first 64 bits of the INT_EVENT1
register.

Fixes: 7e7a3c815d22 ("USB: typec: tps6598x: Add TPS25750 support")
Cc: [email protected]
Signed-off-by: Javier Carrasco <[email protected]>
---
drivers/usb/typec/tipd/core.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/typec/tipd/core.c b/drivers/usb/typec/tipd/core.c
index 0717cfcd9f8c..7c2f01344860 100644
--- a/drivers/usb/typec/tipd/core.c
+++ b/drivers/usb/typec/tipd/core.c
@@ -604,11 +604,11 @@ static irqreturn_t tps25750_interrupt(int irq, void *data)
if (!tps6598x_read_status(tps, &status))
goto err_clear_ints;

- if ((event[0] | event[1]) & TPS_REG_INT_POWER_STATUS_UPDATE)
+ if (event[0] & TPS_REG_INT_POWER_STATUS_UPDATE)
if (!tps6598x_read_power_status(tps))
goto err_clear_ints;

- if ((event[0] | event[1]) & TPS_REG_INT_DATA_STATUS_UPDATE)
+ if (event[0] & TPS_REG_INT_DATA_STATUS_UPDATE)
if (!tps6598x_read_data_status(tps))
goto err_clear_ints;

@@ -617,7 +617,7 @@ static irqreturn_t tps25750_interrupt(int irq, void *data)
* a plug event. Therefore, we need to check
* for pr/dr status change to set TypeC dr/pr accordingly.
*/
- if ((event[0] | event[1]) & TPS_REG_INT_PLUG_EVENT ||
+ if (event[0] & TPS_REG_INT_PLUG_EVENT ||
tps6598x_has_role_changed(tps, status))
tps6598x_handle_plug_event(tps, status);


--
2.40.1



2024-04-02 11:37:21

by Heikki Krogerus

[permalink] [raw]
Subject: Re: [PATCH RESEND 1/2] usb: typec: tipd: fix event checking for tps25750

On Thu, Mar 28, 2024 at 05:55:51PM +0100, Javier Carrasco wrote:
> In its current form, the interrupt service routine of the tps25750
> checks the event flags in the lowest 64 bits of the interrupt event
> register (event[0]), but also in the upper part (event[1]).
>
> Given that all flags are defined as BIT() or BIT_ULL(), they are
> restricted to the first 64 bits of the INT_EVENT1 register. Including
> the upper part of the register can lead to false positives e.g. if the
> event 64 bits above the one being checked is set, but the one being
> checked is not.
>
> Restrict the flag checking to the first 64 bits of the INT_EVENT1
> register.
>
> Fixes: 7e7a3c815d22 ("USB: typec: tps6598x: Add TPS25750 support")
> Cc: [email protected]
> Signed-off-by: Javier Carrasco <[email protected]>

Acked-by: Heikki Krogerus <[email protected]>

> ---
> drivers/usb/typec/tipd/core.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/usb/typec/tipd/core.c b/drivers/usb/typec/tipd/core.c
> index 0717cfcd9f8c..7c2f01344860 100644
> --- a/drivers/usb/typec/tipd/core.c
> +++ b/drivers/usb/typec/tipd/core.c
> @@ -604,11 +604,11 @@ static irqreturn_t tps25750_interrupt(int irq, void *data)
> if (!tps6598x_read_status(tps, &status))
> goto err_clear_ints;
>
> - if ((event[0] | event[1]) & TPS_REG_INT_POWER_STATUS_UPDATE)
> + if (event[0] & TPS_REG_INT_POWER_STATUS_UPDATE)
> if (!tps6598x_read_power_status(tps))
> goto err_clear_ints;
>
> - if ((event[0] | event[1]) & TPS_REG_INT_DATA_STATUS_UPDATE)
> + if (event[0] & TPS_REG_INT_DATA_STATUS_UPDATE)
> if (!tps6598x_read_data_status(tps))
> goto err_clear_ints;
>
> @@ -617,7 +617,7 @@ static irqreturn_t tps25750_interrupt(int irq, void *data)
> * a plug event. Therefore, we need to check
> * for pr/dr status change to set TypeC dr/pr accordingly.
> */
> - if ((event[0] | event[1]) & TPS_REG_INT_PLUG_EVENT ||
> + if (event[0] & TPS_REG_INT_PLUG_EVENT ||
> tps6598x_has_role_changed(tps, status))
> tps6598x_handle_plug_event(tps, status);
>
>
> --
> 2.40.1

--
heikki