lkml.org 
[lkml]   [2018]   [Jun]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 12/19] mmc: mmci: add variant property to request a reset
Date
From: Ludovic Barre <ludovic.barre@st.com>

Some variants could require a reset.
STM32 sdmmc variant needs to reset hardware block
during the power cycle procedure (for re-initialization)

Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
---
Documentation/devicetree/bindings/mmc/mmci.txt | 2 ++
drivers/mmc/host/mmci.c | 9 +++++++++
drivers/mmc/host/mmci.h | 4 ++++
3 files changed, 15 insertions(+)

diff --git a/Documentation/devicetree/bindings/mmc/mmci.txt b/Documentation/devicetree/bindings/mmc/mmci.txt
index 03796cf..e952707 100644
--- a/Documentation/devicetree/bindings/mmc/mmci.txt
+++ b/Documentation/devicetree/bindings/mmc/mmci.txt
@@ -11,6 +11,8 @@ Required properties:
- compatible : contains "arm,pl18x", "arm,primecell".
- vmmc-supply : phandle to the regulator device tree node, mentioned
as the VCC/VDD supply in the eMMC/SD specs.
+depend of variant:
+- resets : phandle to internal reset line.

Optional properties:
- arm,primecell-periphid : contains the PrimeCell Peripheral ID, it overrides
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 9c00804..87724e1 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -37,6 +37,7 @@
#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>
@@ -1445,6 +1446,14 @@ static int mmci_probe(struct amba_device *dev,

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

+ if (variant->reset) {
+ host->rst = devm_reset_control_get_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 30d3f53..2d7e901 100644
--- a/drivers/mmc/host/mmci.h
+++ b/drivers/mmc/host/mmci.h
@@ -284,6 +284,7 @@ struct mmci_host;
* register.
* @opendrain: bitmask identifying the OPENDRAIN bit inside MMCIPOWER register
* @mmci_dma: Pointer to platform-specific DMA callbacks.
+ * @reset: true if variant has need reset signal.
* @validate_data: if hardware block has specific constraint on validate data
* @set_clk_ios: if clock procedure of variant is specific
* @set_pwr_ios: if power procedure of variant is specific
@@ -329,6 +330,7 @@ struct variant_data {
u32 start_err;
u32 opendrain;
struct mmci_dma_ops *mmci_dma;
+ bool reset;
int (*validate_data)(struct mmci_host *host, struct mmc_data *data);
void (*set_clkreg)(struct mmci_host *host, unsigned int desired);
void (*set_pwrreg)(struct mmci_host *host, unsigned char power_mode,
@@ -345,6 +347,8 @@ struct mmci_host {
struct clk *clk;
bool singleirq;

+ struct reset_control *rst;
+
spinlock_t lock;

unsigned int mclk;
--
2.7.4
\
 
 \ /
  Last update: 2018-06-12 15:19    [W:0.152 / U:9.820 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site