+ Ulf
On 2017/10/12 20:27, Goldschmidt Simon wrote:
On 2017/9/22 17:40, Shawn Lin wrote:
Still think that should be part of mmc core's behaviour. I try to make
sure the following ugly patch could work for you? And we could move
forward later to see how to do it more gracefully.
Thanks for your response and sorry my answer comes with three weeks delay.
Unfortunately, I had other problems with the board in question up to now.
I can confirm the patch works for me. On the oscilloscope shots, I can clearly
see that the next request gets delayed when R1b tells the host the "card" is busy.
Thanks for testing.
How can we move forward to a clean fix here?
I think mmc core haven't considered this case that we issue a R1b
command from usersapce and check the busy(or poll the CMD13 to get it
right). I was thinking of adding some check for that case but I'm aslo
now thinking could we reuse the functions from mmc_ops.c instead of
directly sending this command to the host drivers. That we better reuse
the checking logic of the existing code, for instance, mmc_switch.
Ulf, do you have some comment here?
Regards,
Simon
@@ -546,6 +546,24 @@ static int __mmc_blk_ioctl_cmd(struct mmc_card
*card, struct mmc_blk_data *md,
return err;
}
+ /*
+ * Don't try to rely on the host drivers to check the busy status
+ * and do it for here. Maybe it's worth more condiction check
+ * to see if this cmd use data line or not, as we could still
support
+ * cmd in flight even the the device is busy, for instance CQE.
Andt
+ * not sure how much time need to be a proper arbitrary, so bindly
+ * resort to MMC_BLK_TIMEOUT_MS. Also not sure if we need to take
+ * poll mathod if no card_busy available.
+ */
+ if (card->host->ops->card_busy) {
+ int tries = MMC_BLK_TIMEOUT_MS;
+ while (host->ops->card_busy(card->host) && --tries)
+ mmc_delay(1);
+
+ if (tries == 0)
+ return -ETIMEDOUT;
+ }
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