From 541527728341b4bb9a5e3428b0eec450f1b3d8d5 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 25 Sep 2017 01:30:51 +0200 Subject: PM: i2c-designware-platdrv: Suspend/resume at the late/early stages As reported by Rajat Jain, there are problems when ACPI operation region handlers or similar, called at the ->resume_early() time, for I2C client devices try to access an I2C controller that has already been suspended at that point. To avoid that, move the suspend/resume of i2c-designware-platdrv to the late/early stages, respectively. While at it, avoid resuming the device from runtime suspend in the driver's ->suspend callback which isn't particularly nice. [A better approach would be to make the driver track the PM state of the device so that it doesn't need to resume it in ->suspend, so implement it.] First, drop dw_i2c_plat_suspend() added by commit a23318feeff6 (i2c: designware: Fix system suspend) and rename dw_i2c_plat_runtime_suspend() back to dw_i2c_plat_suspend(). Second, point the driver's ->late_suspend and ->early_resume callbacks, rather than its ->suspend and ->resume callbacks, to dw_i2c_plat_suspend() and dw_i2c_plat_resume(), respectively, so that they are not executed in parallel with each other, for example if runtime resume of the device takes place during system suspend. Finally, add "suspended" and "skip_resume" flags to struct dw_i2c_dev and make dw_i2c_plat_suspend() and dw_i2c_plat_resume() use them to avoid suspending or resuming the device twice in a row and to avoid resuming a previously runtime-suspended device during system resume. Signed-off-by: Rafael J. Wysocki Tested-by: Jarkko Nikula Tested-by: Mika Westerberg Tested-by: Johannes Stezenbach Tested-by: Rajat Jain Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-designware-core.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/i2c/busses/i2c-designware-core.h') diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h index 9fee4c054d3d..21bf619a86c5 100644 --- a/drivers/i2c/busses/i2c-designware-core.h +++ b/drivers/i2c/busses/i2c-designware-core.h @@ -280,6 +280,8 @@ struct dw_i2c_dev { int (*acquire_lock)(struct dw_i2c_dev *dev); void (*release_lock)(struct dw_i2c_dev *dev); bool pm_disabled; + bool suspended; + bool skip_resume; void (*disable)(struct dw_i2c_dev *dev); void (*disable_int)(struct dw_i2c_dev *dev); int (*init)(struct dw_i2c_dev *dev); -- cgit