diff mbox series

[V4,19/25] mmc: mmci: add variant property to not read datacnt

Message ID 1538482167-13819-20-git-send-email-ludovic.Barre@st.com (mailing list archive)
State New, archived
Headers show
Series mmc: mmci: add sdmmc variant for stm32 | expand

Commit Message

Ludovic BARRE Oct. 2, 2018, 12:09 p.m. UTC
From: Ludovic Barre <ludovic.barre@st.com>

This patch adds a boolean property to not read datacnt register.
Needed to support the STM32 sdmmc variant. MMCIDATACNT
register should be read only after the data transfer is completed.
When reading after an error event the read data count value may be
different from the real number of data bytes transferred.

Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
---
 drivers/mmc/host/mmci.c | 8 ++++++--
 drivers/mmc/host/mmci.h | 3 +++
 2 files changed, 9 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index e639841..969b665 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -1118,8 +1118,12 @@  mmci_data_irq(struct mmci_host *host, struct mmc_data *data,
 		 * can be as much as a FIFO-worth of data ahead.  This
 		 * matters for FIFO overruns only.
 		 */
-		remain = readl(host->base + MMCIDATACNT);
-		success = data->blksz * data->blocks - remain;
+		if (!host->variant->datacnt_useless) {
+			remain = readl(host->base + MMCIDATACNT);
+			success = data->blksz * data->blocks - remain;
+		} else {
+			success = 0;
+		}
 
 		dev_dbg(mmc_dev(host->mmc), "MCI ERROR IRQ, status 0x%08x at 0x%08x\n",
 			status_err, success);
diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h
index 4e5c6c6..33c243f 100644
--- a/drivers/mmc/host/mmci.h
+++ b/drivers/mmc/host/mmci.h
@@ -224,6 +224,8 @@  struct mmci_host;
  * @datactrl_blksz: block size in power of two
  * @datactrl_dpsm_enable: enable value for DPSM
  * @datactrl_first: true if data must be setup before send command
+ * @datacnt_useless: true if you could not use datacnt register to read
+ *		     remaining data
  * @pwrreg_powerup: power up value for MMCIPOWER register
  * @f_max: maximum clk frequency supported by the controller.
  * @signal_direction: input/out direction of bus signals can be indicated
@@ -264,6 +266,7 @@  struct variant_data {
 	unsigned int		datactrl_blocksz;
 	unsigned int		datactrl_dpsm_enable;
 	u8			datactrl_first:1;
+	u8			datacnt_useless:1;
 	u8			st_sdio:1;
 	u8			st_clkdiv:1;
 	u8			blksz_datactrl16:1;