mmc: mmci: add variant property to set command stop bit

On cmd12 (STOP_TRANSMISSION), STM32 sdmmc variant needs to set
cmdstop bit in command register. The CPSM ("Command Path State Machine")
treats the command as a Stop Transmission command and signals
abort to the DPSM ("Data Path State Machine").

Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

2 files changed, 8 insertions, 0 deletions

diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 13fa640d86d6..e352f5ad5801 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -21,6 +21,7 @@
 #include <linux/err.h>
 #include <linux/highmem.h>
 #include <linux/log2.h>
+#include <linux/mmc/mmc.h>
 #include <linux/mmc/pm.h>
 #include <linux/mmc/host.h>
 #include <linux/mmc/card.h>
@@ -274,6 +275,7 @@ static struct variant_data variant_stm32_sdmmc = {
         .cmdreg_lrsp_crc        = MCI_CPSM_STM32_LRSP_CRC,
         .cmdreg_srsp_crc        = MCI_CPSM_STM32_SRSP_CRC,
         .cmdreg_srsp            = MCI_CPSM_STM32_SRSP,
+        .cmdreg_stop            = MCI_CPSM_STM32_CMDSTOP,
         .data_cmd_enable        = MCI_CPSM_STM32_CMDTRANS,
         .irq_pio_mask           = MCI_IRQ_PIO_STM32_MASK,
         .datactrl_first         = true,
@@ -1100,6 +1102,10 @@ mmci_start_command(struct mmci_host *host, struct mmc_command *cmd, u32 c)
                 mmci_reg_delay(host);
         }
 
+        if (host->variant->cmdreg_stop &&
+            cmd->opcode == MMC_STOP_TRANSMISSION)
+                c |= host->variant->cmdreg_stop;
+
         c |= cmd->opcode | host->variant->cmdreg_cpsm_enable;
         if (cmd->flags & MMC_RSP_PRESENT) {
                 if (cmd->flags & MMC_RSP_136)
diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h
index 550dd3914461..24229097d05c 100644
--- a/drivers/mmc/host/mmci.h
+++ b/drivers/mmc/host/mmci.h
@@ -264,6 +264,7 @@ struct mmci_host;
  * @cmdreg_lrsp_crc: enable value for long response with crc
  * @cmdreg_srsp_crc: enable value for short response with crc
  * @cmdreg_srsp: enable value for short response without crc
+ * @cmdreg_stop: enable value for stop and abort transmission
  * @datalength_bits: number of bits in the MMCIDATALENGTH register
  * @fifosize: number of bytes that can be written when MMCI_TXFIFOEMPTY
  *            is asserted (likewise for RX)
@@ -316,6 +317,7 @@ struct variant_data {
         unsigned int            cmdreg_lrsp_crc;
         unsigned int            cmdreg_srsp_crc;
         unsigned int            cmdreg_srsp;
+        unsigned int            cmdreg_stop;
         unsigned int            datalength_bits;
         unsigned int            fifosize;
         unsigned int            fifohalfsize;