Hi,
On 27.01.21 00:38, Jaehoon Chung wrote:
Hi,
On 1/23/21 9:37 PM, Stefan Bosch wrote:
After issuing the switch command: Wait until 'current state' of the card
status becomes 'tran'. This prevents from response timeout at the next
command because of 'current state' = 'data'.>
Signed-off-by: Stefan Bosch <stefa...@posteo.net>
---
drivers/mmc/mmc.c | 3 ++-
include/mmc.h | 1 +
2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index a47700e313..8ccd2058a9 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -823,7 +823,8 @@ static int __mmc_switch(struct mmc *mmc, u8 set, u8 index,
u8 value,
value);
return -EIO;
}
- if (!ret && (status & MMC_STATUS_RDY_FOR_DATA))
+ if (!ret && (status & MMC_STATUS_RDY_FOR_DATA) &&
+ (status & MMC_STATUS_CURR_STATE) == MMC_STATE_TRANS)
AFAIK, MMC_STATUS_RDY_FOR_DATA bit means the signaling about "buffer is empty".
Even though its bit was set, does it need to check TRANS state?
Best Regards,
Jaehoon Chung
After issuing command 'MMC_CMD_SWITCH' = CMD6 the state transits to
'DATA'. But in DATA state it is not possible to issue a (new) CMD except
CMD12 (operation complete) and CMD7 (select/deselect card). See
appropriate State Diagram, e.g. "Figure 4-3: SD Memory Card State
Diagram (data transfer mode)" in "SD Specifications Part 1 - Physical
Layer - Simplified Specification - Version 2.00". Status 'Ready For
Data' is in my opinion only relevant for CMD12 and CMD7.
Regards
Stefan Bosch
return 0;
udelay(100);
} while (get_timer(start) < timeout_ms);
diff --git a/include/mmc.h b/include/mmc.h
index 1d377e0281..18402494c6 100644
--- a/include/mmc.h
+++ b/include/mmc.h
@@ -178,6 +178,7 @@ static inline bool mmc_is_tuning_cmd(uint cmdidx)
#define MMC_STATUS_ERROR (1 << 19)
#define MMC_STATE_PRG (7 << 9)
+#define MMC_STATE_TRANS (4 << 9)
#define MMC_VDD_165_195 0x00000080 /* VDD voltage 1.65 - 1.95 */
#define MMC_VDD_20_21 0x00000100 /* VDD voltage 2.0 ~ 2.1 */
