spi: spi-s3c64xx: Fix system resume support

BugLink: http://bugs.launchpad.net/bugs/1815234
commit e935dba111621bd6a0c5d48e6511a4d9885103b4 upstream.

Since Linux v4.10 release (commit 1d9174fbc55e "PM / Runtime: Defer
resuming of the device in pm_runtime_force_resume()"),
pm_runtime_force_resume() function doesn't runtime resume device if it was
not runtime active before system suspend. Thus, driver should not do any
register access after pm_runtime_force_resume() without checking the
runtime status of the device. To fix this issue, simply move
s3c64xx_spi_hwinit() call to s3c64xx_spi_runtime_resume() to ensure that
hardware is always properly initialized. This fixes Synchronous external
abort issue on system suspend/resume cycle on newer Exynos SoCs.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index de7df20f8712dd74dc074e763555891f076b820f..8a2adf0e945284b4de1de1f5db0978063e1837da 100644 (file)
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -1270,8 +1270,6 @@ static int s3c64xx_spi_resume(struct device *dev)
        if (ret < 0)
                return ret;
 
-       s3c64xx_spi_hwinit(sdd, sdd->port_id);
-
        return spi_master_resume(master);
 }
 #endif /* CONFIG_PM_SLEEP */
@@ -1309,6 +1307,8 @@ static int s3c64xx_spi_runtime_resume(struct device *dev)
        if (ret != 0)
                goto err_disable_src_clk;
 
+       s3c64xx_spi_hwinit(sdd, sdd->port_id);
+
        return 0;
 
 err_disable_src_clk: