[PATCH 2/2] mmc: dw_mmc: add hw_reset extension hook

From: Shawn Lin
Date: Thu Oct 22 2015 - 02:34:03 EST


This patch add hw_reset for dw_mmc to implement hw reset
procedure. It's useful for mmc core to recover emmc devices
if emmc runs into unexpected state. Add MMC_CAP_HW_RESET
capability to dw_mmc extension driver directly if it needs hw_reset.

Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
---

drivers/mmc/host/dw_mmc.c | 4 ++++
drivers/mmc/host/dw_mmc.h | 2 ++
2 files changed, 6 insertions(+)

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 8a0f2995..46b12de 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -1482,6 +1482,10 @@ static void dw_mci_hw_reset(struct mmc_host *mmc)
{
struct dw_mci_slot *slot = mmc_priv(mmc);
struct dw_mci *host = slot->host;
+ const struct dw_mci_drv_data *drv_data = host->drv_data;
+
+ if (drv_data && drv_data->hw_reset)
+ return drv_data->hw_reset(host);

if (host->use_dma == TRANS_MODE_IDMAC)
dw_mci_idmac_reset(host);
diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h
index 9df18c1..21b9df4 100644
--- a/drivers/mmc/host/dw_mmc.h
+++ b/drivers/mmc/host/dw_mmc.h
@@ -282,6 +282,7 @@ struct dw_mci_slot {
* @set_ios: handle bus specific extensions.
* @parse_dt: parse implementation specific device tree properties.
* @execute_tuning: implementation specific tuning procedure.
+ * @hw_reset: implementation specific hw reset procedure.
*
* Provide controller implementation specific extensions. The usage of this
* data structure is fully optional and usage of each member in this structure
@@ -299,5 +300,6 @@ struct dw_mci_drv_data {
struct mmc_ios *ios);
int (*switch_voltage)(struct mmc_host *mmc,
struct mmc_ios *ios);
+ void (*hw_reset)(struct dw_mci *host);
};
#endif /* _DW_MMC_H_ */
--
2.3.7


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