[PATCH 2/2] spi: atmel: add PM support to SAMA5D2

From: Quentin Schulz
Date: Wed Apr 12 2017 - 03:06:09 EST


This adds PM support to the ATMEL SAMA5D2 Xplained.

When suspending, VDDCore is shut down and the SPI registers are lost.
Thus, the SPI controller needs to be re-initialized after resuming from
a system suspend.

Signed-off-by: Quentin Schulz <quentin.schulz@xxxxxxxxxxxxxxxxxx>
---
drivers/spi/spi-atmel.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 247d920..1eb83c9 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -1702,8 +1702,17 @@ static int atmel_spi_suspend(struct device *dev)
static int atmel_spi_resume(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
+ struct atmel_spi *as = spi_master_get_devdata(master);
int ret;

+ ret = clk_prepare_enable(as->clk);
+ if (ret)
+ return ret;
+
+ atmel_spi_init(as);
+
+ clk_disable_unprepare(as->clk);
+
if (!pm_runtime_suspended(dev)) {
ret = atmel_spi_runtime_resume(dev);
if (ret)
--
2.9.3