i2c: designware: Never suspend i2c-busses used for accessing the system PMIC

Currently we are already setting a pm_runtime_disabled flag and disabling
runtime-pm for i2c-busses used for accessing the system PMIC on x86.
But this is not enough, there are ACPI opregions which may want to access
the PMIC during late-suspend and early-resume, so we need to completely
disable pm to be safe.

This commit renames the flag from pm_runtime_disabled to pm_disabled and
adds the following new behavior if the flag is set:

1) Call dev_pm_syscore_device(dev, true) which disables normal suspend /
   resume and remove the pm_runtime_disabled check from dw_i2c_plat_resume
   since that will now never get called. This fixes suspend_late handlers
   which use ACPI PMIC opregions causing errors like these:

  PM: Suspending system (freeze)
  PM: suspend of devices complete after 1127.751 msecs
  i2c_designware 808622C1:06: timeout waiting for bus ready
  ACPI Exception: AE_ERROR, Returned by Handler for [UserDefinedRegion]
  acpi 80860F14:02: Failed to change power state to D3hot
  PM: late suspend of devices failed

2) Set IRQF_NO_SUSPEND irq flag. This fixes resume_early handlers which
   handlers which use ACPI PMIC opregions causing errors like these:

  PM: resume from suspend-to-idle
  i2c_designware 808622C1:06: controller timed out
  ACPI Exception: AE_ERROR, Returned by Handler for [UserDefinedRegion]

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h
index 846ea57f85af..a7cf429daf60 100644
--- a/drivers/i2c/busses/i2c-designware-core.h
+++ b/drivers/i2c/busses/i2c-designware-core.h
@@ -79,7 +79,7 @@
  * @pm_qos: pm_qos_request used while holding a hardware lock on the bus
  * @acquire_lock: function to acquire a hardware lock on the bus
  * @release_lock: function to release a hardware lock on the bus
- * @pm_runtime_disabled: true if pm runtime is disabled
+ * @pm_disabled: true if power-management should be disabled for this i2c-bus
  *
  * HCNT and LCNT parameters can be used if the platform knows more accurate
  * values than the one computed based only on the input clock frequency.
@@ -128,7 +128,7 @@ struct dw_i2c_dev {
 	struct pm_qos_request	pm_qos;
 	int			(*acquire_lock)(struct dw_i2c_dev *dev);
 	void			(*release_lock)(struct dw_i2c_dev *dev);
-	bool			pm_runtime_disabled;
+	bool			pm_disabled;
 };
 
 #define ACCESS_SWAP		0x00000001