[PATCH 1/2] mmc: core: use card pointer as the first parameter of execute_tuning()

addy ke addy.ke at rock-chips.com
Mon Feb 2 01:02:30 PST 2015

On 2015/2/2 16:17, Ulf Hansson wrote:
> On 2 February 2015 at 09:16, Ulf Hansson <ulf.hansson at linaro.org> wrote:
>>>> about bus_ops->alive, I think it can't use in tuning state.
>>>> Because:
>>>> bus_ops->alive() --> mmc_sd_alive(host) /* sd card */ -->mmc_send_status(host->card, NULL);
>>>> But host->card == NULL in tuning state(mmc_sd_init_card->mmc_sd_init_uhs_card).
>>>> Only if sd is initialized successfully, we can get card pointer by host->card.
>>>> see: mmc_sd_init_card(drivers/mmc/core/sd.c), the end of this function: host->card = card
>>> And bus_ops->alive only check whether mmc is alive or not, the second parameter(*status) is NULL,
>>> We can not get the card status.
>>> But in tuning state, we need wait until card is idle, if the previous tuning is failed.
>> You are right that we can't use bus_ops->alive() in its current form.
>> Changing it to take "card" and "status" as parameter should fix this
>> for us. My point was more that we can't use mmc_send_status() since
>> that doesn't work for SDIO.

For sdio, I think maybe we can use CMD7 to get sdio status.

And there are 3 file which need get card status at least:
1. drivers/mmc/core/mmc_ops.c: mmc_send_status()
2. drivers/mmc/card/block.c: get_card_status()
3. drivers/mmc/card/mmc_test.c: mmc_test_wait_busy()
Maybe we need merge them and provide uniform interface for them.

>> Anyway, it seems like we need to put this patchset on hold for a while.
>> You I merge the below patch instead so we at least have something
> /s /You / Should
>> working for 3.20?
This patch can work, but it need delay 10ms each tuning.
It is too slow to initialize the card(tuning time >= (10 * tuning_count) ms)
>> [PATCH] mmc: dw_mmc: rockchip: Add DW_MCI_QUIRK_RETRY_DELAY
>> https://lkml.org/lkml/2015/1/13/562
>> Kind regards
>> Uffe

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