Re: [PATCH 2/5] mmc: core: switch to 1V8 or 1V2 for hs400es mode

Ulf Hansson
2016-09-22T09:39:30Z

On 21 September 2016 at 03:43, Shawn Lin <shawn.lin@rock-chips.com> wrote:
> When introducing hs400es, I didn't notice that we haven't
> switched voltage to 1V2 or 1V8 for it. That happens to work
> as the first controller claiming to support hs400es, arasan(5.1),
> which is designed to only support 1V8. So the voltage is fixed to 1V8.
> But it actually is wrong, and will not fit for other host controllers.
> Let's fix it.
>
> Fixes: commit 81ac2af65793ecf ("mmc: core: implement enhanced strobe support")
> Cc: <stable@vger.kernel.org> 4.4# +
> Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
> ---
>
> drivers/mmc/core/mmc.c | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
> index 3486bc7..3163bb9 100644
> --- a/drivers/mmc/core/mmc.c
> +++ b/drivers/mmc/core/mmc.c
> @@ -1263,6 +1263,16 @@ static int mmc_select_hs400es(struct mmc_card *card)
> goto out_err;
> }
>
> + if (card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS200_1_2V)

/s/EXT_CSD_CARD_TYPE_HS200_1_2V/EXT_CSD_CARD_TYPE_HS400_1_2V

> + err = __mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_120);
> +
> + if (err && card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS200_1_8V)

/s/EXT_CSD_CARD_TYPE_HS200_1_8V/EXT_CSD_CARD_TYPE_HS400_1_8V

> + err = __mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180);
> +
> + /* If fails try again during next card power cycle */
> + if (err)
> + goto out_err;
> +
> err = mmc_select_bus_width(card);
> if (err < 0)
> goto out_err;
> --
> 2.3.7
>
>

Kind regards
Uffe