spi: rspi: Fix invalid SPI use during system suspend

If the SPI queue is running during system suspend, the system may lock
up.

Fix this by stopping/restarting the queue during system suspend/resume,
by calling spi_master_suspend()/spi_master_resume() from the PM
callbacks.  In-kernel users will receive an -ESHUTDOWN error while
system suspend/resume is in progress.

Based on a patch for sh-msiof by Gaku Inami.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

1 files changed, 24 insertions, 0 deletions

diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c
index 95dc4d78618d..f93a4587e3fb 100644
--- a/drivers/spi/spi-rspi.c
+++ b/drivers/spi/spi-rspi.c
@@ -1350,12 +1350,36 @@ static const struct platform_device_id spi_driver_ids[] = {
 
 MODULE_DEVICE_TABLE(platform, spi_driver_ids);
 
+#ifdef CONFIG_PM_SLEEP
+static int rspi_suspend(struct device *dev)
+{
+        struct platform_device *pdev = to_platform_device(dev);
+        struct rspi_data *rspi = platform_get_drvdata(pdev);
+
+        return spi_master_suspend(rspi->master);
+}
+
+static int rspi_resume(struct device *dev)
+{
+        struct platform_device *pdev = to_platform_device(dev);
+        struct rspi_data *rspi = platform_get_drvdata(pdev);
+
+        return spi_master_resume(rspi->master);
+}
+
+static SIMPLE_DEV_PM_OPS(rspi_pm_ops, rspi_suspend, rspi_resume);
+#define DEV_PM_OPS      &rspi_pm_ops
+#else
+#define DEV_PM_OPS      NULL
+#endif /* CONFIG_PM_SLEEP */
+
 static struct platform_driver rspi_driver = {
         .probe =        rspi_probe,
         .remove =       rspi_remove,
         .id_table =     spi_driver_ids,
         .driver         = {
                 .name = "renesas_spi",
+                .pm = DEV_PM_OPS,
                 .of_match_table = of_match_ptr(rspi_of_match),
         },
 };