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sd: mmc: Remove unwanted request to card for reading OCR content

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As part of the MMC card initialization sequence, CMD1 command send
multiple times to the card, first time to identify the card type and
second time to check the requested voltage window is supported or not.
There is a chance that after issuing the CMD1 for first time, card will
move to the ready state before issuing the CMD1 for second time. In this
case, card will not respond to the CMD1 send for the second time as card
is already moved to ready state and this leads to failures. Hence remove
the separate card identification logic and call mmc_send_op_cond only
once to check both supported voltage window and card type
identification.

Signed-off-by: Paul Alvin <alvin.paulp@amd.com>
This commit is contained in:
Paul Alvin 2025-02-25 10:07:12 +00:00 • committed by Fabio Baltieri
commit c897adb1c6
1 changed files with 6 additions and 14 deletions
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20
subsys/sd/mmc.c
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@ -111,16 +111,6 @@ int mmc_card_init(struct sd_card *card)
return -EINVAL; return -EINVAL;
} }
/* Probe to see if card is an MMC card */
ret = mmc_send_op_cond(card, ocr_arg);
if (ret) {
return ret;
}
/* Card is MMC card if no error
* (Only MMC protocol supports CMD1)
*/
card->type = CARD_MMC;
/* Set OCR Arguments */ /* Set OCR Arguments */
if (card->host_props.host_caps.vol_180_support) { if (card->host_props.host_caps.vol_180_support) {
ocr_arg |= MMC_OCR_VDD170_195FLAG; ocr_arg |= MMC_OCR_VDD170_195FLAG;
@ -137,7 +127,7 @@ int mmc_card_init(struct sd_card *card)
/* CMD1 */ /* CMD1 */
ret = mmc_send_op_cond(card, ocr_arg); ret = mmc_send_op_cond(card, ocr_arg);
if (ret) { if (ret) {
LOG_ERR("Failed to query card OCR"); LOG_DBG("Failed to query card OCR");
return ret; return ret;
} }
@ -221,9 +211,11 @@ static int mmc_send_op_cond(struct sd_card *card, int ocr)
/* OCR failed */ /* OCR failed */
return ret; return ret;
} }
if (ocr == 0) { if (retries == 0) {
/* Just probing */ /* Card is MMC card if no error
return 0; * (Only MMC protocol supports CMD1)
*/
card->type = CARD_MMC;
} }
sd_delay(10); sd_delay(10);
} }