UPSTREAM: spi/rockchip: Make sure spi clk is on in rockchip_spi_set_cs
authorHuibin Hong <huibin.hong@rock-chips.com>
Wed, 24 Feb 2016 10:00:04 +0000 (18:00 +0800)
committerHuang, Tao <huangtao@rock-chips.com>
Fri, 11 Mar 2016 04:12:46 +0000 (12:12 +0800)
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.

Change-Id: I58915aee30cfbd3098eb137e3d9046b59ad9476c
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>
(cherry picked from git.kernel.org broonie/spi.git for-next
 commit b920cc3191d7612f26f36ee494e05b5ffd9044c0)

drivers/spi/spi-rockchip.c

index 345fefd1fc664062f1da3765f889a4b89cda1f48..c4e489cb0022b7e34bbb59da74526041162ef6e5 100644 (file)
@@ -265,7 +265,10 @@ 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;
 
@@ -290,6 +293,8 @@ 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,