lkml.org 
[lkml]   [2019]   [Mar]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/2] spi: spi-mem: stm32-qspi: add suspend/resume support
Date
From: Ludovic Barre <ludovic.barre@st.com>

This patch adds suspend and resume support for spi-stm32-qspi
drivers.

Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
---
drivers/spi/spi-stm32-qspi.c | 39 +++++++++++++++++++++++++++++++++++----
1 file changed, 35 insertions(+), 4 deletions(-)

diff --git a/drivers/spi/spi-stm32-qspi.c b/drivers/spi/spi-stm32-qspi.c
index 7354f9d..3e8ca10 100644
--- a/drivers/spi/spi-stm32-qspi.c
+++ b/drivers/spi/spi-stm32-qspi.c
@@ -13,6 +13,7 @@
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/of_device.h>
+#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include <linux/reset.h>
#include <linux/sizes.h>
@@ -101,6 +102,9 @@ struct stm32_qspi {
struct completion data_completion;
u32 fmode;

+ u32 cr_reg;
+ u32 dcr_reg;
+
/*
* to protect device configuration, could be different between
* 2 flash access (bk1, bk2)
@@ -355,7 +359,7 @@ static int stm32_qspi_setup(struct spi_device *spi)
struct spi_controller *ctrl = spi->master;
struct stm32_qspi *qspi = spi_controller_get_devdata(ctrl);
struct stm32_qspi_flash *flash;
- u32 cr, presc;
+ u32 presc;

if (ctrl->busy)
return -EBUSY;
@@ -371,11 +375,12 @@ static int stm32_qspi_setup(struct spi_device *spi)
flash->presc = presc;

mutex_lock(&qspi->lock);
- cr = FIELD_PREP(CR_FTHRES_MASK, 3) | CR_SSHIFT | CR_EN;
- writel_relaxed(cr, qspi->io_base + QSPI_CR);
+ qspi->cr_reg = FIELD_PREP(CR_FTHRES_MASK, 3) | CR_SSHIFT | CR_EN;
+ writel_relaxed(qspi->cr_reg, qspi->io_base + QSPI_CR);

/* set dcr fsize to max address */
- writel_relaxed(DCR_FSIZE_MASK, qspi->io_base + QSPI_DCR);
+ qspi->dcr_reg = DCR_FSIZE_MASK;
+ writel_relaxed(qspi->dcr_reg, qspi->io_base + QSPI_DCR);
mutex_unlock(&qspi->lock);

return 0;
@@ -489,6 +494,31 @@ static int stm32_qspi_remove(struct platform_device *pdev)
return 0;
}

+static int __maybe_unused stm32_qspi_suspend(struct device *dev)
+{
+ struct stm32_qspi *qspi = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(qspi->clk);
+ pinctrl_pm_select_sleep_state(dev);
+
+ return 0;
+}
+
+static int __maybe_unused stm32_qspi_resume(struct device *dev)
+{
+ struct stm32_qspi *qspi = dev_get_drvdata(dev);
+
+ pinctrl_pm_select_default_state(dev);
+ clk_prepare_enable(qspi->clk);
+
+ writel_relaxed(qspi->cr_reg, qspi->io_base + QSPI_CR);
+ writel_relaxed(qspi->dcr_reg, qspi->io_base + QSPI_DCR);
+
+ return 0;
+}
+
+SIMPLE_DEV_PM_OPS(stm32_qspi_pm_ops, stm32_qspi_suspend, stm32_qspi_resume);
+
static const struct of_device_id stm32_qspi_match[] = {
{.compatible = "st,stm32f469-qspi"},
{}
@@ -501,6 +531,7 @@ static struct platform_driver stm32_qspi_driver = {
.driver = {
.name = "stm32-qspi",
.of_match_table = stm32_qspi_match,
+ .pm = &stm32_qspi_pm_ops,
},
};
module_platform_driver(stm32_qspi_driver);
--
2.7.4
\
 
 \ /
  Last update: 2019-03-08 14:13    [W:0.044 / U:3.040 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site