[PATCH v4 6/6] mtd: spi-nor: cadence-quadspi: Add runtime PM support

From: Vignesh R
Date: Tue Oct 03 2017 - 01:21:27 EST


Add pm_runtime* calls to cadence-quadspi driver. This is required to
switch on QSPI power domain on TI 66AK2G SoC during probe.

Signed-off-by: Vignesh R <vigneshr@xxxxxx>
---
v4: Disable pm in error path.

drivers/mtd/spi-nor/cadence-quadspi.c | 16 +++++++++++++++-
1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/spi-nor/cadence-quadspi.c b/drivers/mtd/spi-nor/cadence-quadspi.c
index 60b557e00cfb..75a2bc447a99 100644
--- a/drivers/mtd/spi-nor/cadence-quadspi.c
+++ b/drivers/mtd/spi-nor/cadence-quadspi.c
@@ -31,6 +31,7 @@
#include <linux/of_device.h>
#include <linux/of.h>
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#include <linux/sched.h>
#include <linux/spi/spi.h>
#include <linux/timer.h>
@@ -1224,10 +1225,17 @@ static int cqspi_probe(struct platform_device *pdev)
return -ENXIO;
}

+ pm_runtime_enable(dev);
+ ret = pm_runtime_get_sync(dev);
+ if (ret < 0) {
+ pm_runtime_put_noidle(dev);
+ return ret;
+ }
+
ret = clk_prepare_enable(cqspi->clk);
if (ret) {
dev_err(dev, "Cannot enable QSPI clock.\n");
- return ret;
+ goto probe_clk_failed;
}

cqspi->master_ref_clk_hz = clk_get_rate(cqspi->clk);
@@ -1259,6 +1267,9 @@ static int cqspi_probe(struct platform_device *pdev)
cqspi_controller_enable(cqspi, 0);
probe_irq_failed:
clk_disable_unprepare(cqspi->clk);
+probe_clk_failed:
+ pm_runtime_put_sync(dev);
+ pm_runtime_disable(dev);
return ret;
}

@@ -1275,6 +1286,9 @@ static int cqspi_remove(struct platform_device *pdev)

clk_disable_unprepare(cqspi->clk);

+ pm_runtime_put_sync(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+
return 0;
}

--
2.14.1