mmc: Allow tuning to be prevented during card initialization

Add a new field to the mmc_host struct to track when the card should never retune and use it to conditionally stop tuning in the mmc_sd_init_uhs_card function. Currently the new field only gets set when a DDR50 card fails to tune, which indicates the card does not support tuning. Signed-off-by: Erick Shepherd <[email protected]>
ni · Jan 23, 2025 · a99a2bc · a99a2bc
1 parent 8680ea0
commit a99a2bc
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Showing 2 changed files with 4 additions and 1 deletion.
diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
@@ -668,7 +668,8 @@ static int mmc_sd_init_uhs_card(struct mmc_card *card)
 	if (!mmc_host_is_spi(card->host) &&
 		(card->host->ios.timing == MMC_TIMING_UHS_SDR50 ||
 		 card->host->ios.timing == MMC_TIMING_UHS_DDR50 ||
-		 card->host->ios.timing == MMC_TIMING_UHS_SDR104)) {
+		 card->host->ios.timing == MMC_TIMING_UHS_SDR104) &&
+		 !card->host->never_retune) {
 		err = mmc_execute_tuning(card);
 
 		/*
@@ -681,6 +682,7 @@ static int mmc_sd_init_uhs_card(struct mmc_card *card)
 		if (err && card->host->ios.timing == MMC_TIMING_UHS_DDR50) {
 			pr_warn("%s: ddr50 tuning failed\n",
 				mmc_hostname(card->host));
+			card->host->never_retune = 1;
 			err = 0;
 		}
 	}

diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
@@ -451,6 +451,7 @@ struct mmc_host {
 	unsigned int		claimed:1;	/* host exclusively claimed */
 	unsigned int		doing_init_tune:1; /* initial tuning in progress */
 	unsigned int		can_retune:1;	/* re-tuning can be used */
+	unsigned int		never_retune:1;	/* re-tuning can never be used */
 	unsigned int		doing_retune:1;	/* re-tuning in progress */
 	unsigned int		retune_now:1;	/* do re-tuning at next req */
 	unsigned int		retune_paused:1; /* re-tuning is temporarily disabled */