spi/rockchip: Make sure spi clk is on in rockchip_spi_set_cs

Rockchip_spi_set_cs could be called by spi_setup, but
spi_setup may be called by device driver after runtime suspend.
Then the spi clock is closed, rockchip_spi_set_cs may access the
spi registers, which causes cpu block in some socs.

Fixes: 64e36824b32 ("spi/rockchip: add driver for Rockchip RK3xxx")
Signed-off-by: Huibin Hong <huibin.hong@rock-chips.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
index 07c082aa5cff5fa7a7475ee716f2ea99bcf9258c..6cdb4d81d66c87842f5ffd3a045bee3f161dd12e 100644 (file)
--- a/drivers/spi/spi-rockchip.c
+++ b/drivers/spi/spi-rockchip.c
@@ -263,7 +263,10 @@ static inline u32 rx_max(struct rockchip_spi *rs)
 static void rockchip_spi_set_cs(struct spi_device *spi, bool enable)
 {
        u32 ser;
-       struct rockchip_spi *rs = spi_master_get_devdata(spi->master);
+       struct spi_master *master = spi->master;
+       struct rockchip_spi *rs = spi_master_get_devdata(master);
+
+       pm_runtime_get_sync(rs->dev);
 
        ser = readl_relaxed(rs->regs + ROCKCHIP_SPI_SER) & SER_MASK;
 
@@ -288,6 +291,8 @@ static void rockchip_spi_set_cs(struct spi_device *spi, bool enable)
                ser &= ~(1 << spi->chip_select);
 
        writel_relaxed(ser, rs->regs + ROCKCHIP_SPI_SER);
+
+       pm_runtime_put_sync(rs->dev);
 }
 
 static int rockchip_spi_prepare_message(struct spi_master *master,