[PATCH v1 1/2] [SRU][F:linux-bluefield] mmc: dw_mmc: Add support for platform specific eMMC HW reset

[Liming Sun]

BugLink: https://bugs.launchpad.net/bugs/2089455

This commit adds a new callback to allow drivers to support platform
specific eMMC HW reset.

Reviewed-by: David Thompson <davthompson at nvidia.com>
Signed-off-by: Liming Sun <limings at nvidia.com>
Link: https://lore.kernel.org/r/3df02ffa8bdaa74f5261c8914d2545b97fb3478a.1718213918.git.limings@nvidia.com
Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>
(cherry picked from commit f21adcb86653e2b2784bbc0f180c332b50c404df mmc)
Signed-off-by: Liming Sun <limings at nvidia.com>
Acked-by: Bartlomiej Zolnierkiewicz <bartlomiej.zolnierkiewicz at canonical.com>
Acked-by: Manuel Diewald <manuel.diewald at canonical.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bartlomiej.zolnierkiewicz at canonical.com>
Signed-off-by: Liming Sun <limings at nvidia.com>
---
 drivers/mmc/host/dw_mmc.c | 6 ++++++
 drivers/mmc/host/dw_mmc.h | 2 ++
 2 files changed, 8 insertions(+)

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 7c5ce9c..60cbcd1 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -1581,6 +1581,7 @@ 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;
 	int reset;
 
 	if (host->use_dma == TRANS_MODE_IDMAC)
@@ -1590,6 +1591,11 @@ static void dw_mci_hw_reset(struct mmc_host *mmc)
 				     SDMMC_CTRL_FIFO_RESET))
 		return;
 
+	if (drv_data && drv_data->hw_reset) {
+		drv_data->hw_reset(host);
+		return;
+	}
+
 	/*
 	 * According to eMMC spec, card reset procedure:
 	 * tRstW >= 1us:   RST_n pulse width
diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h
index da5923a..4eff99d 100644
--- a/drivers/mmc/host/dw_mmc.h
+++ b/drivers/mmc/host/dw_mmc.h
@@ -547,6 +547,7 @@ 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.
  *
  * Provide controller implementation specific extensions. The usage of this
  * data structure is fully optional and usage of each member in this structure
@@ -563,5 +564,6 @@ 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_ */
-- 
1.8.3.1