Re: [PATCH 1/3] mmc: sdhci: fix SDHCI_QUIRK2_CLEAR_TRANSFERMODE_REG_BEFORE_CMD handling

From: Adrian Hunter
Date: Tue Jan 09 2018 - 07:35:14 EST


On 28/12/17 11:59, ernest.zhang wrote:
> SD controller with SDHCI_QUIRK2_CLEAR_TRANSFERMODE_REG_BEFORE_CMD quirk
> will clear SD host transfer mode register for non-data commands. But in
> eMMC HS200 hardware tuning case, the hardware tuning process need to
> transfer mode register has properly value. So don't clear transfer
> mode register when opcode equals to MMC_SEND_TUNING_BLOCK_HS200.

As I wrote last time, you send MMC_SEND_TUNING_BLOCK_HS200 with data != NULL
so this code path is not used.

Also please use version numbers in the subject.

>
> Signed-off-by: ernest.zhang <ernest.zhang@xxxxxxxxxxxxxx>
> ---
> drivers/mmc/host/sdhci.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 0d5fcca18c9e..d5b19fc9ea56 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -918,7 +918,9 @@ static void sdhci_set_transfer_mode(struct sdhci_host *host,
> if (data == NULL) {
> if (host->quirks2 &
> SDHCI_QUIRK2_CLEAR_TRANSFERMODE_REG_BEFORE_CMD) {
> - sdhci_writew(host, 0x0, SDHCI_TRANSFER_MODE);
> + /* cannot clear transfer mode register when tuning */
> + if (cmd->opcode != MMC_SEND_TUNING_BLOCK_HS200)
> + sdhci_writew(host, 0x0, SDHCI_TRANSFER_MODE);
> } else {
> /* clear Auto CMD settings for no data CMDs */
> mode = sdhci_readw(host, SDHCI_TRANSFER_MODE);
>