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authorThomas Richard <thomas.richard@bootlin.com>2024-06-13 15:13:28 +0200
committerAndi Shyti <andi.shyti@kernel.org>2024-07-09 00:46:07 +0200
commit7da7fd7e66ac9b0d4287aefba516795145f3c722 (patch)
tree78b10527339df2fe00b67fb2b74193834a3880b2
parent2cb21a62bacc53587095b2050e92ce3e7a3574d7 (diff)
i2c: omap: wakeup the controller during suspend() callback
A device may need the controller up during suspend_noirq() or resume_noirq(). But if the controller is autosuspended, there is no way to wakeup it during suspend_noirq() or resume_noirq() because runtime pm is disabled at this time. The suspend() callback wakes up the controller, so it is available until its suspend_noirq() callback (pm_runtime_force_suspend()). During the resume, it's restored by resume_noirq() callback (pm_runtime_force_resume()). Then resume() callback enables autosuspend. So the controller is up during a little time slot in suspend and resume sequences even if it's not used. Reviewed-by: Andi Shyti <andi.shyti@kernel.org> Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Thomas Richard <thomas.richard@bootlin.com> Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
-rw-r--r--drivers/i2c/busses/i2c-omap.c22
1 files changed, 22 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 410c8b37f768..35a3f0a64986 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -1574,9 +1574,31 @@ static int omap_i2c_runtime_resume(struct device *dev)
return 0;
}
+static int omap_i2c_suspend(struct device *dev)
+{
+ /*
+ * If the controller is autosuspended, there is no way to wakeup it once
+ * runtime pm is disabled (in suspend_late()).
+ * But a device may need the controller up during suspend_noirq() or
+ * resume_noirq().
+ * Wakeup the controller while runtime pm is enabled, so it is available
+ * until its suspend_noirq(), and from resume_noirq().
+ */
+ return pm_runtime_resume_and_get(dev);
+}
+
+static int omap_i2c_resume(struct device *dev)
+{
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_put_autosuspend(dev);
+
+ return 0;
+}
+
static const struct dev_pm_ops omap_i2c_pm_ops = {
NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
pm_runtime_force_resume)
+ SYSTEM_SLEEP_PM_OPS(omap_i2c_suspend, omap_i2c_resume)
RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
omap_i2c_runtime_resume, NULL)
};