[PATCH next 1/1] spi: sifive: add PM callbacks to support suspend/resume

[Andy Chiu <andy.chiu@xxxxxxxxxx>]

Signed-off-by: Andy Chiu <andy.chiu@xxxxxxxxxx>
Reviewed-by: Greentime Hu <greentime.hu@xxxxxxxxxx>
---
 drivers/spi/spi-sifive.c | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/drivers/spi/spi-sifive.c b/drivers/spi/spi-sifive.c
index f7c1e20432e0..e29e85cee88a 100644
--- a/drivers/spi/spi-sifive.c
+++ b/drivers/spi/spi-sifive.c
@@ -427,6 +427,44 @@ static int sifive_spi_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static int sifive_spi_suspend(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct sifive_spi *spi = spi_master_get_devdata(master);
+	int ret;
+
+	ret = spi_master_suspend(master);
+	if (ret)
+		return ret;
+
+	/* Disable all the interrupts just in case */
+	sifive_spi_write(spi, SIFIVE_SPI_REG_IE, 0);
+
+	clk_disable_unprepare(spi->clk);
+
+	return ret;
+}
+
+static int sifive_spi_resume(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct sifive_spi *spi = spi_master_get_devdata(master);
+	int ret;
+
+	ret = clk_prepare_enable(spi->clk);
+	if (ret)
+		return ret;
+	ret = spi_master_resume(master);
+	if (ret)
+		clk_disable_unprepare(spi->clk);
+
+	return ret;
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(sifive_spi_pm_ops,
+				sifive_spi_suspend, sifive_spi_resume);
+
+
 static const struct of_device_id sifive_spi_of_match[] = {
 	{ .compatible = "sifive,spi0", },
 	{}
@@ -438,6 +476,7 @@ static struct platform_driver sifive_spi_driver = {
 	.remove = sifive_spi_remove,
 	.driver = {
 		.name = SIFIVE_SPI_DRIVER_NAME,
+		.pm = &sifive_spi_pm_ops,
 		.of_match_table = sifive_spi_of_match,
 	},
 };
-- 
2.36.0