[PATCH 2/2] mmc: mmci: add quirk property to add stm32 transfer mode

[Ludovic Barre]

From: Ludovic Barre <ludovic.barre@xxxxxx>

This patch adds a quirk bit to define specific stm32 transfer
modes. sdmmc data transfer mode selection could be:
-Block data transfer ending on block count.
-SDIO multibyte data transfer.
-MMC Stream data transfer (not used).
-Block data transfer ending with STOP_TRANSMISSION command.

Signed-off-by: Ludovic Barre <ludovic.barre@xxxxxx>
---
 drivers/mmc/host/mmci.c | 11 +++++++++++
 drivers/mmc/host/mmci.h |  7 +++++++
 2 files changed, 18 insertions(+)

diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 387ff14..44c721a 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -284,6 +284,7 @@ static struct variant_data variant_stm32_sdmmc = {
 	.datactrl_blocksz	= 14,
 	.stm32_idmabsize_mask	= GENMASK(12, 5),
 	.init			= sdmmc_variant_init,
+	.quirks			= MMCI_QUIRK_STM32_DTMODE,
 };
 
 static struct variant_data variant_qcom = {
@@ -1028,6 +1029,16 @@ static void mmci_start_data(struct mmci_host *host, struct mmc_data *data)
 	else
 		datactrl = variant->datactrl_dpsm_enable | blksz_bits << 4;
 
+	if (variant->quirks & MMCI_QUIRK_STM32_DTMODE) {
+		if (host->mmc->card && mmc_card_sdio(host->mmc->card) &&
+		    data->blocks == 1)
+			datactrl |= MCI_DPSM_STM32_MODE_SDIO;
+		else if (data->stop && !host->mrq->sbc)
+			datactrl |= MCI_DPSM_STM32_MODE_BLOCK_STOP;
+		else
+			datactrl |= MCI_DPSM_STM32_MODE_BLOCK;
+	}
+
 	if (data->flags & MMC_DATA_READ)
 		datactrl |= MCI_DPSM_DIRECTION;
 
diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h
index 474f4fa..9fbd0a4 100644
--- a/drivers/mmc/host/mmci.h
+++ b/drivers/mmc/host/mmci.h
@@ -131,6 +131,11 @@
 /* Control register extensions in the Qualcomm versions */
 #define MCI_DPSM_QCOM_DATA_PEND	BIT(17)
 #define MCI_DPSM_QCOM_RX_DATA_PEND BIT(20)
+/* Control register extensions in STM32 versions */
+#define MCI_DPSM_STM32_MODE_BLOCK	(0 << 2)
+#define MCI_DPSM_STM32_MODE_SDIO	(1 << 2)
+#define MCI_DPSM_STM32_MODE_STREAM	(2 << 2)
+#define MCI_DPSM_STM32_MODE_BLOCK_STOP	(3 << 2)
 
 #define MMCIDATACNT		0x030
 #define MMCISTATUS		0x034
@@ -357,6 +362,8 @@ struct variant_data {
 	void (*init)(struct mmci_host *host);
 };
 
+#define MMCI_QUIRK_STM32_DTMODE	BIT(0)
+
 /* mmci variant callbacks */
 struct mmci_host_ops {
 	int (*validate_data)(struct mmci_host *host, struct mmc_data *data);
-- 
2.7.4