[PATCH] spi: qup: Handle clocks in pm_runtime suspend and resume

From: Pramod Gurav
Date: Mon May 02 2016 - 08:14:03 EST


Clocks must ne disabled in pm_runtime to achieve some power saving.
Enable the clocks when the device is runtime resumed during a transfer.

Signed-off-by: Pramod Gurav <pramod.gurav@xxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
drivers/spi/spi-qup.c | 13 +++++++++++++
1 file changed, 13 insertions(+)

diff --git a/drivers/spi/spi-qup.c b/drivers/spi/spi-qup.c
index 810a7fae3479..e42ff613c0e0 100644
--- a/drivers/spi/spi-qup.c
+++ b/drivers/spi/spi-qup.c
@@ -937,6 +937,10 @@ static int spi_qup_pm_suspend_runtime(struct device *device)
config = readl(controller->base + QUP_CONFIG);
config |= QUP_CONFIG_CLOCK_AUTO_GATE;
writel_relaxed(config, controller->base + QUP_CONFIG);
+
+ clk_disable_unprepare(controller->cclk);
+ clk_disable_unprepare(controller->iclk);
+
return 0;
}

@@ -945,6 +949,15 @@ static int spi_qup_pm_resume_runtime(struct device *device)
struct spi_master *master = dev_get_drvdata(device);
struct spi_qup *controller = spi_master_get_devdata(master);
u32 config;
+ int ret;
+
+ ret = clk_prepare_enable(controller->iclk);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(controller->cclk);
+ if (ret)
+ return ret;

/* Disable clocks auto gaiting */
config = readl_relaxed(controller->base + QUP_CONFIG);
--
2.8.1