[PATCH V4 21/25] mmc: mmci: add optional reset property

From: Ludovic Barre
Date: Tue Oct 02 2018 - 08:11:08 EST


From: Ludovic Barre <ludovic.barre@xxxxxx>

This patch adds a optional reset management.
STM32 sdmmc variant needs to reset hardware block
during the power cycle procedure (for re-initialization).

Signed-off-by: Ludovic Barre <ludovic.barre@xxxxxx>
---
drivers/mmc/host/mmci.c | 7 +++++++
drivers/mmc/host/mmci.h | 2 ++
2 files changed, 9 insertions(+)

diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 969b665..0898cc9 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -36,6 +36,7 @@
#include <linux/pm_runtime.h>
#include <linux/types.h>
#include <linux/pinctrl/consumer.h>
+#include <linux/reset.h>

#include <asm/div64.h>
#include <asm/io.h>
@@ -1877,6 +1878,12 @@ static int mmci_probe(struct amba_device *dev,

dev_dbg(mmc_dev(mmc), "clocking block at %u Hz\n", mmc->f_max);

+ host->rst = devm_reset_control_get_optional_exclusive(&dev->dev, NULL);
+ if (IS_ERR(host->rst)) {
+ ret = PTR_ERR(host->rst);
+ goto clk_disable;
+ }
+
/* Get regulators and the supported OCR mask */
ret = mmc_regulator_get_supply(mmc);
if (ret)
diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h
index 33c243f..f793426 100644
--- a/drivers/mmc/host/mmci.h
+++ b/drivers/mmc/host/mmci.h
@@ -318,6 +318,8 @@ struct mmci_host {
struct clk *clk;
u8 singleirq:1;

+ struct reset_control *rst;
+
spinlock_t lock;

unsigned int mclk;
--
2.7.4