On Thu, 14 Nov 2019 at 12:18, Yangbo Lu <yangbo.lu@xxxxxxx> wrote:
>
> The STOP command is disabled for multiple blocks r/w commands
> with auto CMD12, when start to send. However, if there is data
> error, software still needs to send CMD12 according to SD spec.
> This patch is to allow software CMD12 sending for this case.
>
> Signed-off-by: Yangbo Lu <yangbo.lu@xxxxxxx>
> ---
> drivers/mmc/host/sdhci.c | 17 +++--------------
> 1 file changed, 3 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 09cdbe8..3041c39 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -1326,12 +1326,12 @@ static void sdhci_finish_data(struct sdhci_host *host)
>
> /*
> * Need to send CMD12 if -
> - * a) open-ended multiblock transfer (no CMD23)
> + * a) open-ended multiblock transfer not using auto CMD12 (no CMD23)
> * b) error in multiblock transfer
> */
> if (data->stop &&
> - (data->error ||
> - !data->mrq->sbc)) {
> + ((!data->mrq->sbc && !sdhci_auto_cmd12(host, data->mrq)) ||
> + data->error)) {
Per your other reply to this thread, I don't think there is any harm
in always sending a CMD12 if there is an error, at least from the
card's point of view.
The worst thing that can happen is that there are two CMD12 sent to
the card and I don't think that is a problem for the error path.
My only concern, is to understand if $subject patch causes other
changes in behaviours for the SDHCI driver. Let's see what Adrian
thinks.
> /*
> * 'cap_cmd_during_tfr' request must not use the command line
> * after mmc_command_done() has been called. It is upper layer's
> @@ -1825,17 +1825,6 @@ void sdhci_request(struct mmc_host *mmc, struct mmc_request *mrq)
>
> sdhci_led_activate(host);
>
> - /*
> - * Ensure we don't send the STOP for non-SET_BLOCK_COUNTED
> - * requests if Auto-CMD12 is enabled.
> - */
> - if (sdhci_auto_cmd12(host, mrq)) {
> - if (mrq->stop) {
> - mrq->data->stop = NULL;
> - mrq->stop = NULL;
> - }
> - }
In general, I am not very fond of when host drivers change these
structures under the hood of the core, which means I like this part.
> -
> if (!present || host->flags & SDHCI_DEVICE_DEAD) {
> mrq->cmd->error = -ENOMEDIUM;
> sdhci_finish_mrq(host, mrq);
> --
> 2.7.4
>
Kind regards
Uffe
