[PATCH] mmc: core: increase the number of retries of the ACMD41

[Felix Qin <xiaokeqinhealth@126.com>]

Extensive testing has shown that a few specific SD cards require
an increase in the number of command retries to successfully
initialize.

Signed-off-by: Felix Qin <xiaokeqinhealth@126.com>
---
 drivers/mmc/core/sd_ops.c | 4 ++--
 drivers/mmc/core/sd_ops.h | 8 ++++++++
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/core/sd_ops.c b/drivers/mmc/core/sd_ops.c
index a59cd592f06e..b3b6e8725b80 100644
--- a/drivers/mmc/core/sd_ops.c
+++ b/drivers/mmc/core/sd_ops.c
@@ -127,7 +127,7 @@ int mmc_send_app_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr)
 		cmd.arg = ocr;
 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R3 | MMC_CMD_BCR;
 
-	for (i = 100; i; i--) {
+	for (i = SD_APP_OP_COND_RETRIES; i; i--) {
 		err = mmc_wait_for_app_cmd(host, NULL, &cmd);
 		if (err)
 			break;
@@ -147,7 +147,7 @@ int mmc_send_app_op_cond(struct mmc_host *host, u32 ocr, u32 *rocr)
 
 		err = -ETIMEDOUT;
 
-		mmc_delay(10);
+		mmc_delay(SD_APP_OP_COND_INTERVAL);
 	}
 
 	if (!i)
diff --git a/drivers/mmc/core/sd_ops.h b/drivers/mmc/core/sd_ops.h
index 7667fc223b74..80c5c836ccd1 100644
--- a/drivers/mmc/core/sd_ops.h
+++ b/drivers/mmc/core/sd_ops.h
@@ -10,6 +10,14 @@
 
 #include <linux/types.h>
 
+/*
+ * Extensive testing has shown that a few specific SD cards require
+ * an increase in the number of command retries to successfully
+ * initialize.
+ */
+#define SD_APP_OP_COND_RETRIES  200
+#define SD_APP_OP_COND_INTERVAL 10	/* millisecond */
+
 struct mmc_card;
 struct mmc_host;
 
-- 
2.34.1