[PATCH v7 02/24] mfd: max77686: Add power management support
From: Javier Martinez Canillas <hidden>
Date: 2014-07-04 20:31:58
Also in:
linux-devicetree, linux-samsung-soc, lkml
Subsystem:
maxim pmic and muic drivers for exynos based boards, multifunction devices (mfd), the rest · Maintainers:
Chanwoo Choi, Krzysztof Kozlowski, Lee Jones, Linus Torvalds
The driver doesn't have PM operations defined so add a suspend and resume function handlers to allow the PMIC IRQ to wakeup the system when it is put into a sleep state. Signed-off-by: Javier Martinez Canillas <redacted> Reviewed-by: Krzysztof Kozlowski <redacted> --- drivers/mfd/max77686.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+)
diff --git a/drivers/mfd/max77686.c b/drivers/mfd/max77686.c
index 3cb41d0..a38e9ee 100644
--- a/drivers/mfd/max77686.c
+++ b/drivers/mfd/max77686.c@@ -240,10 +240,50 @@ static const struct i2c_device_id max77686_i2c_id[] = { }; MODULE_DEVICE_TABLE(i2c, max77686_i2c_id); +#ifdef CONFIG_PM_SLEEP +static int max77686_suspend(struct device *dev) +{ + struct i2c_client *i2c = container_of(dev, struct i2c_client, dev); + struct max77686_dev *max77686 = i2c_get_clientdata(i2c); + + if (device_may_wakeup(dev)) + enable_irq_wake(max77686->irq); + + /* + * IRQ must be disabled during suspend because if it happens + * while suspended it will be handled before resuming I2C. + * + * When device is woken up from suspend (e.g. by RTC wake alarm), + * an interrupt occurs before resuming I2C bus controller. + * Interrupt handler tries to read registers but this read + * will fail because I2C is still suspended. + */ + disable_irq(max77686->irq); + + return 0; +} + +static int max77686_resume(struct device *dev) +{ + struct i2c_client *i2c = container_of(dev, struct i2c_client, dev); + struct max77686_dev *max77686 = i2c_get_clientdata(i2c); + + if (device_may_wakeup(dev)) + disable_irq_wake(max77686->irq); + + enable_irq(max77686->irq); + + return 0; +} +#endif /* CONFIG_PM_SLEEP */ + +static SIMPLE_DEV_PM_OPS(max77686_pm, max77686_suspend, max77686_resume); + static struct i2c_driver max77686_i2c_driver = { .driver = { .name = "max77686", .owner = THIS_MODULE, + .pm = &max77686_pm, .of_match_table = of_match_ptr(max77686_pmic_dt_match), }, .probe = max77686_i2c_probe,
--
2.0.0.rc2