6.8-stable review patch. If anyone has any objections, please let me know.
------------------
From: Maksim Kiselev <bigunclemax@xxxxxxxxx>
commit ace323f80b9bc6734289a4e8a77938a3ce964c7d upstream.
Fix SD card tuning error by increasing tuning loop count
from 40(MAX_TUNING_LOOP) to 128.
For some reason the tuning algorithm requires to move through all the taps
of delay line even if the THRESHOLD_MODE (bit 2 in AT_CTRL_R) is used
instead of the LARGEST_WIN_MODE.
Tested-by: Drew Fustini <drew@xxxxxxxx>
Tested-by: Xi Ruoyao <xry111@xxxxxxxxxxx>
Signed-off-by: Maksim Kiselev <bigunclemax@xxxxxxxxx>
Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Fixes: 43658a542ebf ("mmc: sdhci-of-dwcmshc: Add support for T-Head TH1520")
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20240402093539.184287-1-bigunclemax@xxxxxxxxx
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/mmc/host/sdhci-of-dwcmshc.c | 1 +
1 file changed, 1 insertion(+)
--- a/drivers/mmc/host/sdhci-of-dwcmshc.c
+++ b/drivers/mmc/host/sdhci-of-dwcmshc.c
@@ -612,6 +612,7 @@ static int th1520_execute_tuning(struct
/* perform tuning */
sdhci_start_tuning(host);
+ host->tuning_loop_count = 128;
host->tuning_err = __sdhci_execute_tuning(host, opcode);
if (host->tuning_err) {
/* disable auto-tuning upon tuning error */
