Commit 9b8e1052 authored Sep 28, 2017 by Sagar Dharia

i2c: qcom: geni: Turn off resources during system-suspend if needed



I2C clients may need the bus to do transactions while system suspend
is in progress. While Runtime-PM resume turns on resources
successfully for such transactions, runtime-suspend callback is not
called by put_sync method to avoid race between runtime PM and system
PM frameworks.
Turn off resources if this condition is detected during I2C bus
system suspend callback, and set the runtime-PM status to be
consistent with the hardware. If however, transaction is still
ongoing during noirq suspend callback, abort suspend by returning
-EBUSY.

Change-Id: Id93afa765bf97babcb6a9c6922d25f108afdc7f3
Signed-off-by: Sagar Dharia <sdharia@codeaurora.org>

parent 856db920

drivers/i2c/busses/i2c-qcom-geni.c

+16 −1

Original line number	Diff line number	Diff line
		@@ -910,8 +910,23 @@ static int geni_i2c_runtime_resume(struct device *dev)

		static int geni_i2c_suspend_noirq(struct device *device)
		{
		if (!pm_runtime_status_suspended(device))
		struct geni_i2c_dev *gi2c = dev_get_drvdata(device);
		int ret;

		/* Make sure no transactions are pending */
		ret = i2c_trylock_bus(&gi2c->adap, I2C_LOCK_SEGMENT);
		if (!ret) {
		GENI_SE_ERR(gi2c->ipcl, true, gi2c->dev,
		"late I2C transaction request\n");
		return -EBUSY;
		}
		if (!pm_runtime_status_suspended(device)) {
		geni_i2c_runtime_suspend(device);
		pm_runtime_disable(device);
		pm_runtime_set_suspended(device);
		pm_runtime_enable(device);
		}
		i2c_unlock_bus(&gi2c->adap, I2C_LOCK_SEGMENT);
		return 0;
		}
		#else