[PATCH 1/3] spi: add power control when set_cs_timing

[Leilk Liu]

From: "leilk.liu" <leilk.liu at mediatek.com>

As to set_cs_timing takes effect immediately, power spi
is needed when call spi_set_cs_timing.

Signed-off-by: leilk.liu <leilk.liu at mediatek.com>
---
 drivers/spi/spi.c | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index a17efa8c3047..21ea3e8a00e2 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -3460,11 +3460,30 @@ EXPORT_SYMBOL_GPL(spi_setup);
 int spi_set_cs_timing(struct spi_device *spi, struct spi_delay *setup,
 		      struct spi_delay *hold, struct spi_delay *inactive)
 {
+	struct device *parent = spi->controller->dev.parent;
 	size_t len;
+	int status;
+
+	if (spi->controller->set_cs_timing) {
+		if (spi->controller->auto_runtime_pm) {
+			status = pm_runtime_get_sync(parent);
+			if (status < 0) {
+				pm_runtime_put_noidle(parent);
+				dev_err(&spi->controller->dev, "Failed to power device: %d\n",
+					status);
+				return status;
+			}
 
-	if (spi->controller->set_cs_timing)
-		return spi->controller->set_cs_timing(spi, setup, hold,
-						      inactive);
+			status = spi->controller->set_cs_timing(spi, setup,
+								hold, inactive);
+			pm_runtime_mark_last_busy(parent);
+			pm_runtime_put_autosuspend(parent);
+			return status;
+		} else {
+			return spi->controller->set_cs_timing(spi, setup, hold,
+							      inactive);
+		}
+	}
 
 	if ((setup && setup->unit == SPI_DELAY_UNIT_SCK) ||
 	    (hold && hold->unit == SPI_DELAY_UNIT_SCK) ||
-- 
2.18.0