Commit 419be8e1 authored by Alain Volmat's avatar Alain Volmat Committed by Wolfram Sang
Browse files

i2c: stm32f7: allow controller to be wakeup-source 



Allow the i2c-stm32f7 controller to become a wakeup-source
of the system. In such case, when a slave is registered to the
I2C controller, receiving a I2C message targeting that registered
slave address wakes up the suspended system.

In order to be able to wake-up, the I2C controller DT node
must have the property wakeup-source defined and a slave
must be registered.

Signed-off-by: default avatarAlain Volmat <alain.volmat@st.com>
Reviewed-by: default avatarPierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
parent 3a5ee18d

drivers/i2c/busses/i2c-stm32f7.c

+86 −21
Original line number Diff line number Diff line
@@ -29,6 +29,7 @@ 
#include <linux/platform_device.h>

#include <linux/pinctrl/consumer.h>

#include <linux/pm_runtime.h>

#include <linux/pm_wakeirq.h>

#include <linux/regmap.h>

#include <linux/reset.h>

#include <linux/slab.h>
@@ -49,6 +50,7 @@ 


/* STM32F7 I2C control 1 */

#define STM32F7_I2C_CR1_PECEN			BIT(23)

#define STM32F7_I2C_CR1_WUPEN			BIT(18)

#define STM32F7_I2C_CR1_SBC			BIT(16)

#define STM32F7_I2C_CR1_RXDMAEN			BIT(15)

#define STM32F7_I2C_CR1_TXDMAEN			BIT(14)
@@ -301,6 +303,7 @@ struct stm32f7_i2c_msg { 
 * @dma: dma data

 * @use_dma: boolean to know if dma is used in the current transfer

 * @regmap: holds SYSCFG phandle for Fast Mode Plus bits

 * @wakeup_src: boolean to know if the device is a wakeup source

 */

struct stm32f7_i2c_dev {

	struct i2c_adapter adap;
@@ -323,6 +326,7 @@ struct stm32f7_i2c_dev { 
	struct stm32_i2c_dma *dma;

	bool use_dma;

	struct regmap *regmap;

	bool wakeup_src;

};



/*
@@ -1691,6 +1695,24 @@ pm_free: 
	return ret;

}



static void stm32f7_i2c_enable_wakeup(struct stm32f7_i2c_dev *i2c_dev,

				      bool enable)

{

	void __iomem *base = i2c_dev->base;

	u32 mask = STM32F7_I2C_CR1_WUPEN;



	if (!i2c_dev->wakeup_src)

		return;



	if (enable) {

		device_set_wakeup_enable(i2c_dev->dev, true);

		stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask);

	} else {

		device_set_wakeup_enable(i2c_dev->dev, false);

		stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, mask);

	}

}



static int stm32f7_i2c_reg_slave(struct i2c_client *slave)

{

	struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(slave->adapter);
@@ -1717,6 +1739,9 @@ static int stm32f7_i2c_reg_slave(struct i2c_client *slave) 
	if (ret < 0)

		return ret;



	if (!stm32f7_i2c_is_slave_registered(i2c_dev))

		stm32f7_i2c_enable_wakeup(i2c_dev, true);



	if (id == 0) {

		/* Configure Own Address 1 */

		oar1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR1);
@@ -1758,6 +1783,9 @@ static int stm32f7_i2c_reg_slave(struct i2c_client *slave) 


	ret = 0;

pm_free:

	if (!stm32f7_i2c_is_slave_registered(i2c_dev))

		stm32f7_i2c_enable_wakeup(i2c_dev, false);



	pm_runtime_mark_last_busy(dev);

	pm_runtime_put_autosuspend(dev);
@@ -1791,8 +1819,10 @@ static int stm32f7_i2c_unreg_slave(struct i2c_client *slave) 


	i2c_dev->slave[id] = NULL;



	if (!(stm32f7_i2c_is_slave_registered(i2c_dev)))

	if (!stm32f7_i2c_is_slave_registered(i2c_dev)) {

		stm32f7_i2c_disable_irq(i2c_dev, STM32F7_I2C_ALL_IRQ_MASK);

		stm32f7_i2c_enable_wakeup(i2c_dev, false);

	}



	pm_runtime_mark_last_busy(i2c_dev->dev);

	pm_runtime_put_autosuspend(i2c_dev->dev);
@@ -1879,6 +1909,9 @@ static int stm32f7_i2c_probe(struct platform_device *pdev) 
		return irq_error ? : -ENOENT;

	}



	i2c_dev->wakeup_src = of_property_read_bool(pdev->dev.of_node,

						    "wakeup-source");



	i2c_dev->clk = devm_clk_get(&pdev->dev, NULL);

	if (IS_ERR(i2c_dev->clk)) {

		dev_err(&pdev->dev, "Error: Missing controller clock\n");
@@ -1985,6 +2018,16 @@ static int stm32f7_i2c_probe(struct platform_device *pdev) 
		goto clk_free;

	}



	if (i2c_dev->wakeup_src) {

		device_set_wakeup_capable(i2c_dev->dev, true);



		ret = dev_pm_set_wake_irq(i2c_dev->dev, irq_event);

		if (ret) {

			dev_err(i2c_dev->dev, "Failed to set wake up irq\n");

			goto clr_wakeup_capable;

		}

	}



	platform_set_drvdata(pdev, i2c_dev);



	pm_runtime_set_autosuspend_delay(i2c_dev->dev,
@@ -2014,6 +2057,13 @@ pm_disable: 
	pm_runtime_set_suspended(i2c_dev->dev);

	pm_runtime_dont_use_autosuspend(i2c_dev->dev);



	if (i2c_dev->wakeup_src)

		dev_pm_clear_wake_irq(i2c_dev->dev);



clr_wakeup_capable:

	if (i2c_dev->wakeup_src)

		device_set_wakeup_capable(i2c_dev->dev, false);



	if (i2c_dev->dma) {

		stm32_i2c_dma_free(i2c_dev->dma);

		i2c_dev->dma = NULL;
@@ -2032,6 +2082,15 @@ static int stm32f7_i2c_remove(struct platform_device *pdev) 
	i2c_del_adapter(&i2c_dev->adap);

	pm_runtime_get_sync(i2c_dev->dev);



	if (i2c_dev->wakeup_src) {

		dev_pm_clear_wake_irq(i2c_dev->dev);

		/*

		 * enforce that wakeup is disabled and that the device

		 * is marked as non wakeup capable

		 */

		device_init_wakeup(i2c_dev->dev, false);

	}



	pm_runtime_put_noidle(i2c_dev->dev);

	pm_runtime_disable(i2c_dev->dev);

	pm_runtime_set_suspended(i2c_dev->dev);
@@ -2073,8 +2132,8 @@ static int __maybe_unused stm32f7_i2c_runtime_resume(struct device *dev) 
	return 0;

}



static int __maybe_unused

stm32f7_i2c_regs_backup(struct stm32f7_i2c_dev *i2c_dev)

#ifdef CONFIG_PM_SLEEP

static int stm32f7_i2c_regs_backup(struct stm32f7_i2c_dev *i2c_dev)

{

	int ret;

	struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs;
@@ -2095,8 +2154,7 @@ stm32f7_i2c_regs_backup(struct stm32f7_i2c_dev *i2c_dev) 
	return ret;

}



static int __maybe_unused

stm32f7_i2c_regs_restore(struct stm32f7_i2c_dev *i2c_dev)

static int stm32f7_i2c_regs_restore(struct stm32f7_i2c_dev *i2c_dev)

{

	u32 cr1;

	int ret;
@@ -2127,12 +2185,14 @@ stm32f7_i2c_regs_restore(struct stm32f7_i2c_dev *i2c_dev) 
	return ret;

}



static int __maybe_unused stm32f7_i2c_suspend(struct device *dev)

static int stm32f7_i2c_suspend(struct device *dev)

{

	struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);

	int ret;



	i2c_mark_adapter_suspended(&i2c_dev->adap);



	if (!device_may_wakeup(dev) && !dev->power.wakeup_path) {

		ret = stm32f7_i2c_regs_backup(i2c_dev);

		if (ret < 0) {

			i2c_mark_adapter_resumed(&i2c_dev->adap);
@@ -2141,15 +2201,17 @@ static int __maybe_unused stm32f7_i2c_suspend(struct device *dev) 


		pinctrl_pm_select_sleep_state(dev);

		pm_runtime_force_suspend(dev);

	}



	return 0;

}



static int __maybe_unused stm32f7_i2c_resume(struct device *dev)

static int stm32f7_i2c_resume(struct device *dev)

{

	struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);

	int ret;



	if (!device_may_wakeup(dev) && !dev->power.wakeup_path) {

		ret = pm_runtime_force_resume(dev);

		if (ret < 0)

			return ret;
@@ -2158,10 +2220,13 @@ static int __maybe_unused stm32f7_i2c_resume(struct device *dev) 
		ret = stm32f7_i2c_regs_restore(i2c_dev);

		if (ret < 0)

			return ret;

	}



	i2c_mark_adapter_resumed(&i2c_dev->adap);



	return 0;

}

#endif



static const struct dev_pm_ops stm32f7_i2c_pm_ops = {

	SET_RUNTIME_PM_OPS(stm32f7_i2c_runtime_suspend,

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