[PATCH] tpm: display message when using gpio-reset instead of when missing it

[Ilias Apalodimas]

Hi Tim,

On Thu, 21 Mar 2024 at 20:02, Tim Harvey <tharvey at gateworks.com> wrote:
>
> Instead of displaying what looks like an error message if a
> gpio-reset dt prop is missing for a TPM dipslay a more
> informative message about resetting the TPM if the gpio is found:
>
> before:
> tpm_tis_spi_probe: missing reset GPIO
>
> after:
> tpm at 0: performing 1ms reset on gpio at 30210000:12
>
> Note that the reset dt binding prop used in this driver is not
> dt-compliant; it does not exist in the Linux dt-bindings documentation
> and the reset is not done by the Linux driver.

Probably for a good reason. You aren't supposed to be able to reset a
TPM without resetting the CPUI as well no?
That being said, printing that the TPM was reset is pointless imho.
OTOH the existing error message at least points out a potential
problem in the DT.

Thanks
/Ilias
>
> Signed-off-by: Tim Harvey <tharvey at gateworks.com>
> ---
>  drivers/tpm/tpm2_tis_spi.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/tpm/tpm2_tis_spi.c b/drivers/tpm/tpm2_tis_spi.c
> index de9cf8f21e07..944540f7a711 100644
> --- a/drivers/tpm/tpm2_tis_spi.c
> +++ b/drivers/tpm/tpm2_tis_spi.c
> @@ -237,14 +237,14 @@ static int tpm_tis_spi_probe(struct udevice *dev)
>                         /* legacy reset */
>                         ret = gpio_request_by_name(dev, "gpio-reset", 0,
>                                                    &reset_gpio, GPIOD_IS_OUT);
> -                       if (ret) {
> -                               log(LOGC_NONE, LOGL_NOTICE,
> -                                   "%s: missing reset GPIO\n", __func__);
> +                       if (ret)
>                                 goto init;
> -                       }
>                         log(LOGC_NONE, LOGL_NOTICE,
>                             "%s: gpio-reset is deprecated\n", __func__);
>                 }
> +               log(LOGC_NONE, LOGL_NOTICE,
> +                   "%s: performing 1ms reset on %s:%d\n", dev->name,
> +                   reset_gpio.dev->name, reset_gpio.offset);
>                 dm_gpio_set_value(&reset_gpio, 1);
>                 mdelay(1);
>                 dm_gpio_set_value(&reset_gpio, 0);
> --
> 2.25.1
>