Re: [PATCH V4 4/5] mmc: mmci: stm32: define get_dctrl_cfg

[Ludovic BARRE]

On 3/27/19 11:54 AM, Ulf Hansson wrote:
On Wed, 27 Mar 2019 at 10:05, Ludovic Barre <ludovic.ba...@st.com> wrote:

From: Ludovic Barre <ludovic.ba...@st.com>

This patch defines get_dctrl_cfg callback for sdmmc variant.
sdmmc variant has 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.ba...@st.com>
---
  drivers/mmc/host/mmci.h             |  5 +++++
  drivers/mmc/host/mmci_stm32_sdmmc.c | 18 ++++++++++++++++++
  2 files changed, 23 insertions(+)

diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h
index 35c91d0..82e9f94 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
diff --git a/drivers/mmc/host/mmci_stm32_sdmmc.c 
b/drivers/mmc/host/mmci_stm32_sdmmc.c
index cfbfc6f..8e83ae6 100644
--- a/drivers/mmc/host/mmci_stm32_sdmmc.c
+++ b/drivers/mmc/host/mmci_stm32_sdmmc.c
@@ -265,10 +265,28 @@ static void mmci_sdmmc_set_pwrreg(struct mmci_host *host, 
unsigned int pwr)
         }
  }

+static u32 sdmmc_get_dctrl_cfg(struct mmci_host *host)
+{
+       u32 datactrl;
+
+       datactrl = mmci_dctrl_blksz(host);
+
+       if (host->mmc->card && mmc_card_sdio(host->mmc->card) &&
+           host->data->blocks == 1)
+               datactrl |= MCI_DPSM_STM32_MODE_SDIO;
+       else if (host->data->stop && !host->mrq->sbc)
+               datactrl |= MCI_DPSM_STM32_MODE_BLOCK_STOP;

Just a question here. Does this mean that the controller sends the
stop command automatically when a transfer has finished successfully?

The controller not sends the stop command, this bit is just an 
information for the Data State Machine to know how the data transfer 
finish.

Regards,
Ludo


+       else
+               datactrl |= MCI_DPSM_STM32_MODE_BLOCK;
+
+       return datactrl;
+}
+
  static struct mmci_host_ops sdmmc_variant_ops = {
         .validate_data = sdmmc_idma_validate_data,
         .prep_data = sdmmc_idma_prep_data,
         .unprep_data = sdmmc_idma_unprep_data,
+       .get_datactrl_cfg = sdmmc_get_dctrl_cfg,
         .dma_setup = sdmmc_idma_setup,
         .dma_start = sdmmc_idma_start,
         .dma_finalize = sdmmc_idma_finalize,
--
2.7.4


Kind regards
Uffe