Commit 4e7bca6f authored by Pierre-Yves MORDRET's avatar Pierre-Yves MORDRET Committed by Wolfram Sang
Browse files

i2c: i2c-stm32f7: add PM Runtime support 



Use PM Runtime API to enable/disable clock

Signed-off-by: default avatarPierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
parent 5eb316e6

drivers/i2c/busses/i2c-stm32f7.c

+101 −43
Original line number Diff line number Diff line
@@ -28,6 +28,8 @@ 
#include <linux/of_irq.h>

#include <linux/of_platform.h>

#include <linux/platform_device.h>

#include <linux/pinctrl/consumer.h>

#include <linux/pm_runtime.h>

#include <linux/regmap.h>

#include <linux/reset.h>

#include <linux/slab.h>
@@ -165,6 +167,8 @@ 
#define STM32F7_SCLH_MAX			BIT(8)

#define STM32F7_SCLL_MAX			BIT(8)



#define STM32F7_AUTOSUSPEND_DELAY		(HZ / 100)



/**

 * struct stm32f7_i2c_spec - private i2c specification timing

 * @rate: I2C bus speed (Hz)
@@ -1549,15 +1553,13 @@ static int stm32f7_i2c_xfer(struct i2c_adapter *i2c_adap, 
	i2c_dev->msg_id = 0;

	f7_msg->smbus = false;



	ret = clk_enable(i2c_dev->clk);

	if (ret) {

		dev_err(i2c_dev->dev, "Failed to enable clock\n");

	ret = pm_runtime_get_sync(i2c_dev->dev);

	if (ret < 0)

		return ret;

	}



	ret = stm32f7_i2c_wait_free_bus(i2c_dev);

	if (ret)

		goto clk_free;

		goto pm_free;



	stm32f7_i2c_xfer_msg(i2c_dev, msgs);
@@ -1573,8 +1575,9 @@ static int stm32f7_i2c_xfer(struct i2c_adapter *i2c_adap, 
		ret = -ETIMEDOUT;

	}



clk_free:

	clk_disable(i2c_dev->clk);

pm_free:

	pm_runtime_mark_last_busy(i2c_dev->dev);

	pm_runtime_put_autosuspend(i2c_dev->dev);



	return (ret < 0) ? ret : num;

}
@@ -1596,39 +1599,37 @@ static int stm32f7_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, 
	f7_msg->read_write = read_write;

	f7_msg->smbus = true;



	ret = clk_enable(i2c_dev->clk);

	if (ret) {

		dev_err(i2c_dev->dev, "Failed to enable clock\n");

	ret = pm_runtime_get_sync(dev);

	if (ret < 0)

		return ret;

	}



	ret = stm32f7_i2c_wait_free_bus(i2c_dev);

	if (ret)

		goto clk_free;

		goto pm_free;



	ret = stm32f7_i2c_smbus_xfer_msg(i2c_dev, flags, command, data);

	if (ret)

		goto clk_free;

		goto pm_free;



	timeout = wait_for_completion_timeout(&i2c_dev->complete,

					      i2c_dev->adap.timeout);

	ret = f7_msg->result;

	if (ret)

		goto clk_free;

		goto pm_free;



	if (!timeout) {

		dev_dbg(dev, "Access to slave 0x%x timed out\n", f7_msg->addr);

		if (i2c_dev->use_dma)

			dmaengine_terminate_all(dma->chan_using);

		ret = -ETIMEDOUT;

		goto clk_free;

		goto pm_free;

	}



	/* Check PEC */

	if ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK && read_write) {

		ret = stm32f7_i2c_smbus_check_pec(i2c_dev);

		if (ret)

			goto clk_free;

			goto pm_free;

	}



	if (read_write && size != I2C_SMBUS_QUICK) {
@@ -1653,8 +1654,9 @@ static int stm32f7_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, 
		}

	}



clk_free:

	clk_disable(i2c_dev->clk);

pm_free:

	pm_runtime_mark_last_busy(dev);

	pm_runtime_put_autosuspend(dev);

	return ret;

}
@@ -1680,13 +1682,9 @@ static int stm32f7_i2c_reg_slave(struct i2c_client *slave) 
	if (ret)

		return ret;



	if (!(stm32f7_i2c_is_slave_registered(i2c_dev))) {

		ret = clk_enable(i2c_dev->clk);

		if (ret) {

			dev_err(dev, "Failed to enable clock\n");

	ret = pm_runtime_get_sync(dev);

	if (ret < 0)

		return ret;

		}

	}



	if (id == 0) {

		/* Configure Own Address 1 */
@@ -1707,7 +1705,7 @@ static int stm32f7_i2c_reg_slave(struct i2c_client *slave) 
		oar2 &= ~STM32F7_I2C_OAR2_MASK;

		if (slave->flags & I2C_CLIENT_TEN) {

			ret = -EOPNOTSUPP;

			goto exit;

			goto pm_free;

		}



		oar2 |= STM32F7_I2C_OAR2_OA2_7(slave->addr);
@@ -1716,7 +1714,7 @@ static int stm32f7_i2c_reg_slave(struct i2c_client *slave) 
		writel_relaxed(oar2, i2c_dev->base + STM32F7_I2C_OAR2);

	} else {

		ret = -ENODEV;

		goto exit;

		goto pm_free;

	}



	/* Enable ACK */
@@ -1727,11 +1725,10 @@ static int stm32f7_i2c_reg_slave(struct i2c_client *slave) 
		STM32F7_I2C_CR1_PE;

	stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask);



	return 0;



exit:

	if (!(stm32f7_i2c_is_slave_registered(i2c_dev)))

		clk_disable(i2c_dev->clk);

	ret = 0;

pm_free:

	pm_runtime_mark_last_busy(dev);

	pm_runtime_put_autosuspend(dev);



	return ret;

}
@@ -1749,6 +1746,10 @@ static int stm32f7_i2c_unreg_slave(struct i2c_client *slave) 


	WARN_ON(!i2c_dev->slave[id]);



	ret = pm_runtime_get_sync(i2c_dev->dev);

	if (ret < 0)

		return ret;



	if (id == 0) {

		mask = STM32F7_I2C_OAR1_OA1EN;

		stm32f7_i2c_clr_bits(base + STM32F7_I2C_OAR1, mask);
@@ -1759,10 +1760,11 @@ 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);

		clk_disable(i2c_dev->clk);

	}



	pm_runtime_mark_last_busy(i2c_dev->dev);

	pm_runtime_put_autosuspend(i2c_dev->dev);



	return 0;

}
@@ -1847,6 +1849,7 @@ static int stm32f7_i2c_probe(struct platform_device *pdev) 
		dev_err(&pdev->dev, "Error: Missing controller clock\n");

		return PTR_ERR(i2c_dev->clk);

	}



	ret = clk_prepare_enable(i2c_dev->clk);

	if (ret) {

		dev_err(&pdev->dev, "Failed to prepare_enable clock\n");
@@ -1920,8 +1923,6 @@ static int stm32f7_i2c_probe(struct platform_device *pdev) 
	if (ret)

		goto clk_free;



	stm32f7_i2c_hw_config(i2c_dev);



	adap = &i2c_dev->adap;

	i2c_set_adapdata(adap, i2c_dev);

	snprintf(adap->name, sizeof(adap->name), "STM32F7 I2C(%pa)",
@@ -1940,18 +1941,35 @@ static int stm32f7_i2c_probe(struct platform_device *pdev) 
					     STM32F7_I2C_TXDR,

					     STM32F7_I2C_RXDR);



	ret = i2c_add_adapter(adap);

	if (ret)

		goto clk_free;



	platform_set_drvdata(pdev, i2c_dev);



	clk_disable(i2c_dev->clk);

	pm_runtime_set_autosuspend_delay(i2c_dev->dev,

					 STM32F7_AUTOSUSPEND_DELAY);

	pm_runtime_use_autosuspend(i2c_dev->dev);

	pm_runtime_set_active(i2c_dev->dev);

	pm_runtime_enable(i2c_dev->dev);



	pm_runtime_get_noresume(&pdev->dev);



	stm32f7_i2c_hw_config(i2c_dev);



	ret = i2c_add_adapter(adap);

	if (ret)

		goto pm_disable;



	dev_info(i2c_dev->dev, "STM32F7 I2C-%d bus adapter\n", adap->nr);



	pm_runtime_mark_last_busy(i2c_dev->dev);

	pm_runtime_put_autosuspend(i2c_dev->dev);



	return 0;



pm_disable:

	pm_runtime_put_noidle(i2c_dev->dev);

	pm_runtime_disable(i2c_dev->dev);

	pm_runtime_set_suspended(i2c_dev->dev);

	pm_runtime_dont_use_autosuspend(i2c_dev->dev);



clk_free:

	clk_disable_unprepare(i2c_dev->clk);
@@ -1968,11 +1986,50 @@ static int stm32f7_i2c_remove(struct platform_device *pdev) 
	}



	i2c_del_adapter(&i2c_dev->adap);

	pm_runtime_get_sync(i2c_dev->dev);



	clk_disable_unprepare(i2c_dev->clk);



	pm_runtime_put_noidle(i2c_dev->dev);

	pm_runtime_disable(i2c_dev->dev);

	pm_runtime_set_suspended(i2c_dev->dev);

	pm_runtime_dont_use_autosuspend(i2c_dev->dev);



	return 0;

}



#ifdef CONFIG_PM

static int stm32f7_i2c_runtime_suspend(struct device *dev)

{

	struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);



	if (!stm32f7_i2c_is_slave_registered(i2c_dev))

		clk_disable_unprepare(i2c_dev->clk);



	return 0;

}



static int stm32f7_i2c_runtime_resume(struct device *dev)

{

	struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev);

	int ret;



	clk_unprepare(i2c_dev->clk);

	if (!stm32f7_i2c_is_slave_registered(i2c_dev)) {

		ret = clk_prepare_enable(i2c_dev->clk);

		if (ret) {

			dev_err(dev, "failed to prepare_enable clock\n");

			return ret;

		}

	}



	return 0;

}

#endif



static const struct dev_pm_ops stm32f7_i2c_pm_ops = {

	SET_RUNTIME_PM_OPS(stm32f7_i2c_runtime_suspend,

			   stm32f7_i2c_runtime_resume, NULL)

};



static const struct of_device_id stm32f7_i2c_match[] = {

	{ .compatible = "st,stm32f7-i2c", .data = &stm32f7_setup},
@@ -1984,6 +2041,7 @@ static struct platform_driver stm32f7_i2c_driver = { 
	.driver = {

		.name = "stm32f7-i2c",

		.of_match_table = stm32f7_i2c_match,

		.pm = &stm32f7_i2c_pm_ops,

	},

	.probe = stm32f7_i2c_probe,

	.remove = stm32f7_i2c_remove,