[PATCH 2/5] mmc: sdhci: Add quirk to indicate MMC_RSP_136 has CRC

Kishon Vijay Abraham I kishon at ti.com
Mon Aug 21 00:41:29 PDT 2017


TI's implementation of sdhci controller used in DRA7 SoC's has
CRC in responses with length 136 bits. Add quirk to indicate
the controller has CRC in MMC_RSP_136. If this quirk is
set sdhci library shouldn't shift the response present in
SDHCI_RESPONSE register.

Signed-off-by: Kishon Vijay Abraham I <kishon at ti.com>
---
 drivers/mmc/host/sdhci.c | 3 +++
 drivers/mmc/host/sdhci.h | 2 ++
 2 files changed, 5 insertions(+)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index ba639b7851cb..9c8d7428df3c 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1182,6 +1182,9 @@ static void sdhci_read_rsp_136(struct sdhci_host *host, struct mmc_command *cmd)
 		cmd->resp[i] = sdhci_readl(host, reg);
 	}
 
+	if (host->quirks2 & SDHCI_QUIRK2_RSP_136_HAS_CRC)
+		return;
+
 	/* CRC is stripped so we need to do some shifting */
 	for (i = 0; i < 4; i++) {
 		cmd->resp[i] <<= 8;
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 399edc681623..54bc444c317f 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -435,6 +435,8 @@ struct sdhci_host {
 #define SDHCI_QUIRK2_ACMD23_BROKEN			(1<<14)
 /* Broken Clock divider zero in controller */
 #define SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN		(1<<15)
+/* Controller has CRC in 136 bit Command Response */
+#define SDHCI_QUIRK2_RSP_136_HAS_CRC			(1<<16)
 
 	int irq;		/* Device IRQ */
 	void __iomem *ioaddr;	/* Mapped address */
-- 
2.11.0




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