Hi Shawn,
On 05/27/2016 12:02 PM, Shawn Lin wrote:
> The main reason to add this check is to avoid unnecessary
> mmc_request like the on-going cmd and the corresponding sbc
> if the card is removed. Although we have already checked this in
> dw_mci_handle_cd for runtime usage of sd card and dw_mci_init_slot
> for noremovable devices, but there is a timing gap before it really
> calls dw_mci_get_cd as mmc_detect_change needs some delay here.
>
> Another gain here is that we could save some checkings of card status
> after sd card been removed.
>
> Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
> ---
>
> drivers/mmc/host/dw_mmc.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
> index cb30e91..8eb7898 100644
> --- a/drivers/mmc/host/dw_mmc.c
> +++ b/drivers/mmc/host/dw_mmc.c
> @@ -105,6 +105,7 @@ struct idmac_desc {
> static bool dw_mci_reset(struct dw_mci *host);
> static bool dw_mci_ctrl_reset(struct dw_mci *host, u32 reset);
> static int dw_mci_card_busy(struct mmc_host *mmc);
> +static int dw_mci_get_cd(struct mmc_host *mmc);
>
> #if defined(CONFIG_DEBUG_FS)
> static int dw_mci_req_show(struct seq_file *s, void *v)
> @@ -1255,7 +1256,7 @@ static void dw_mci_request(struct mmc_host *mmc, struct mmc_request *mrq)
> */
> spin_lock_bh(&host->lock);
>
> - if (!test_bit(DW_MMC_CARD_PRESENT, &slot->flags)) {
> + if (!dw_mci_get_cd(mmc)) {
> spin_unlock_bh(&host->lock);
> mrq->cmd->error = -ENOMEDIUM;
> mmc_request_done(mmc, mrq);
I think spin_lock/unlock_bh() should be removed at here.
Instead, Can it locate before calling dw_mci_queue_request()?
Anyway, it looks good to me.
Best Regards,
Jaehoon Chung
>
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