[PATCH 02/18] mmc: meson-gx: remove code for unsupported CMD23

[Ulf Hansson]

On 16 February 2017 at 08:03, Heiner Kallweit <hkallweit1 at gmail.com> wrote:
> Am 15.02.2017 um 17:54 schrieb Kevin Hilman:
>> Heiner Kallweit <hkallweit1 at gmail.com> writes:
>>
>>> CMD23 isn't supported on meson-gx and therefore the "set block count"
>>> command isn't used. So remove this dead code.
>>
>> I'm admittedly a bit unfamiliar with the MMC spec and wrote this driver
>> mostly by looking at the vendor driver, so forgive the silly
>> questions...
>>
>> Why isn't CMD23 supported, and should we support instead of deleting
>> this support?
>>
> As far as I understand this needs to be supported by the host controller.
> And setting the respective host flag to enable CMD23 mode lead to a
> non-working driver when testing on my system.

CMD23 can be supported by the host *driver*, you don't need HW-support
to implement this.

You may for example be inspired by the mmci.c driver to understand how
to implement this. Looks for "mrq->sbc".

[...]

Kind regards
Uffe