[PATCH 1/2] spi: atmel: adopt pinctrl support
Wenyou Yang
wenyou.yang at atmel.com
Tue Mar 4 20:58:49 EST 2014
Amend the spi atmel pin controller to optionally take a pin control
handle and set the state of the pins to:
- "default" on boot, resume and before performing an spitransfer
- "sleep" on suspend()
This should make it possible to optimize energy usage for the pins
both for the suspend/resume cycle
Signed-off-by: Wenyou Yang <wenyou.yang at atmel.com>
---
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 b0842f7..54b4436 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -26,6 +26,7 @@
#include <linux/io.h>
#include <linux/gpio.h>
+#include <linux/pinctrl/consumer.h>
/* SPI register offsets */
#define SPI_CR 0x0000
@@ -1303,6 +1304,9 @@ static int atmel_spi_probe(struct platform_device *pdev)
struct spi_master *master;
struct atmel_spi *as;
+ /* Select default pin state */
+ pinctrl_pm_select_default_state(&pdev->dev);
+
regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!regs)
return -ENXIO;
@@ -1457,6 +1461,9 @@ static int atmel_spi_suspend(struct device *dev)
struct atmel_spi *as = spi_master_get_devdata(master);
clk_disable_unprepare(as->clk);
+
+ pinctrl_pm_select_sleep_state(dev);
+
return 0;
}
@@ -1465,6 +1472,8 @@ 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);
+ pinctrl_pm_select_default_state(dev);
+
clk_prepare_enable(as->clk);
return 0;
}
--
1.7.9.5
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