Re: [PATCH 1/3] hwmon: pmbus: Reduce clear fault page invocations

From: Guenter Roeck
Date: Sat Aug 19 2023 - 08:19:29 EST


On Thu, Aug 17, 2023 at 11:25:24AM +0200, Naresh Solanki wrote:
> From: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>
>
> Observing I2C traffic revealed consecutive transmission of CLEAR_FAULT
> commands. While this doesn't cause issues, it extends driver probe time.
>
> Avoid invoking pmbus_clear_fault_page for virtual registers, as they're
> managed by the driver, not the chip.
>
> TEST: Verified using an I2C bus analyzer that only one CLEAR_FAULT
> command is send instead 5 in a row.
>
> Signed-off-by: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>
> Signed-off-by: Naresh Solanki <Naresh.Solanki@xxxxxxxxxxxxx>

Applied.

Thanks,
Guenter

> ---
> drivers/hwmon/pmbus/pmbus_core.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
>
> base-commit: fc8df28be7155ddcf8731b4c85fd3372811ba5ac
>
> diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
> index 69a4e62b6c8d..cbfabdd69056 100644
> --- a/drivers/hwmon/pmbus/pmbus_core.c
> +++ b/drivers/hwmon/pmbus/pmbus_core.c
> @@ -561,7 +561,8 @@ static bool pmbus_check_register(struct i2c_client *client,
> rv = pmbus_check_status_cml(client);
> if (rv < 0 && (data->flags & PMBUS_READ_STATUS_AFTER_FAILED_CHECK))
> data->read_status(client, -1);
> - pmbus_clear_fault_page(client, -1);
> + if (reg < PMBUS_VIRT_BASE)
> + pmbus_clear_fault_page(client, -1);
> return rv >= 0;
> }
>