Re: [PATCH v5 06/12] mmc: sdhci-xenon: Add Marvell Xenon SDHC core functionality

From: Adrian Hunter
Date: Thu Jan 26 2017 - 07:44:58 EST


On 26/01/17 12:50, Ulf Hansson wrote:
> On 11 January 2017 at 18:19, Gregory CLEMENT
> <gregory.clement@xxxxxxxxxxxxxxxxxx> wrote:
>> + priv->init_card_type = MMC_TYPE_MMC;
>> + mmc->caps |= MMC_CAP_NONREMOVABLE;
>> +
>> + /*
>> + * Force to clear BUS_TEST to
>> + * skip bus_test_pre and bus_test_post
>> + */
>> + mmc->caps &= ~MMC_CAP_BUS_WIDTH_TEST;
>> + mmc->caps2 |= MMC_CAP2_HC_ERASE_SZ |
>
> This cap is a bit strange. It was added several years ago by Adrian
> Hunter, but I am wondering about the reason to why it's needed.
>

MMC_CAP2_HC_ERASE_SZ relates to EXT-CSD ERASE_GROUP_DEF.

I think it was added to enable people to choose whether they wanted a large
or small erase granularity. That probably doesn't matter if the card
supports TRIM.