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i2c: omap: Fix PM regression with deferred probe for pm_runtime_reinit 

Commit 5de85b9d57 ("PM / runtime: Re-init runtime PM states at probe
error and driver unbind") introduced pm_runtime_reinit() that is used
to reinitialize PM runtime after -EPROBE_DEFER. This allows shutting
down the device after a failed probe.

However, for drivers using pm_runtime_use_autosuspend() this can cause
a state where suspend callback is never called after -EPROBE_DEFER.
On the following device driver probe, hardware state is different from
the PM runtime state causing omap_device to produce the following
error:

omap_device_enable() called from invalid state 1

And with omap_device and omap hardware being picky for PM, this will
block any deeper idle states in hardware.

The solution is to fix the drivers to follow the PM runtime documentation:

1. For sections of code that needs the device disabled, use
   pm_runtime_put_sync_suspend() if pm_runtime_set_autosuspend() has
   been set.

2. For driver exit code, use pm_runtime_dont_use_autosuspend() before
   pm_runtime_put_sync() if pm_runtime_use_autosuspend() has been
   set.

Fixes: 5de85b9d57 ("PM / runtime: Re-init runtime PM states at probe
error and driver unbind")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
Tony Lindgren 2016-02-10 15:02:45 -08:00 committed by Wolfram Sang
parent 388f7b1d6e
commit e6244deed8
1 changed files with 3 additions and 1 deletions
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4
drivers/i2c/busses/i2c-omap.c
View File

@ -1450,7 +1450,8 @@ omap_i2c_probe(struct platform_device *pdev)
err_unuse_clocks:
omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, 0);
pm_runtime_put(omap->dev);
pm_runtime_dont_use_autosuspend(omap->dev);
pm_runtime_put_sync(omap->dev);
pm_runtime_disable(&pdev->dev);
err_free_mem:
@ -1468,6 +1469,7 @@ static int omap_i2c_remove(struct platform_device *pdev)
return ret;
omap_i2c_write_reg(omap, OMAP_I2C_CON_REG, 0);
pm_runtime_dont_use_autosuspend(&pdev->dev);
pm_runtime_put_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);
return 0;