diff mbox series

[PATCHv2] i2c: i2c-stm32f7: allow controller to be wakeup-source

Message ID 1580752328-26009-1-git-send-email-alain.volmat@st.com (mailing list archive)
State Mainlined
Commit 419be8e1dfed5afa497ca320e1b65954820b48c2
Headers show
Series [PATCHv2] i2c: i2c-stm32f7: allow controller to be wakeup-source | expand

Commit Message

Alain Volmat Feb. 3, 2020, 5:52 p.m. UTC
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: Alain Volmat <alain.volmat@st.com>
---
 v2: - enclose _suspend and _resume functions (and related) with
       #ifdef CONFIG_PM_SLEEP
     - remove the __maybe_unused for functions enclosed with CONFIG_PM_SLEEP
     - move stm32f7_i2c_enable_wakeup function upper in the file to avoid
       having a prototype.
 
 drivers/i2c/busses/i2c-stm32f7.c | 107 +++++++++++++++++++++++++------
 1 file changed, 86 insertions(+), 21 deletions(-)

Comments

Pierre Yves MORDRET Feb. 5, 2020, 3:40 p.m. UTC | #1
Hi all

Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>

Thanks

On 2/3/20 6:52 PM, Alain Volmat wrote:
> 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: Alain Volmat <alain.volmat@st.com>
> ---
>  v2: - enclose _suspend and _resume functions (and related) with
>        #ifdef CONFIG_PM_SLEEP
>      - remove the __maybe_unused for functions enclosed with CONFIG_PM_SLEEP
>      - move stm32f7_i2c_enable_wakeup function upper in the file to avoid
>        having a prototype.
>  
>  drivers/i2c/busses/i2c-stm32f7.c | 107 +++++++++++++++++++++++++------
>  1 file changed, 86 insertions(+), 21 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c
> index 5c3e8ac6ad92..378956ac6d1d 100644
> --- a/drivers/i2c/busses/i2c-stm32f7.c
> +++ b/drivers/i2c/busses/i2c-stm32f7.c
> @@ -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 @@ static int stm32f7_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
>  	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 @@ static int stm32f7_i2c_probe(struct platform_device *pdev)
>  	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;
> @@ -2127,41 +2185,48 @@ 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);
> -	ret = stm32f7_i2c_regs_backup(i2c_dev);
> -	if (ret < 0) {
> -		i2c_mark_adapter_resumed(&i2c_dev->adap);
> -		return ret;
> -	}
>  
> -	pinctrl_pm_select_sleep_state(dev);
> -	pm_runtime_force_suspend(dev);
> +	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);
> +			return ret;
> +		}
> +
> +		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;
>  
> -	ret = pm_runtime_force_resume(dev);
> -	if (ret < 0)
> -		return ret;
> -	pinctrl_pm_select_default_state(dev);
> +	if (!device_may_wakeup(dev) && !dev->power.wakeup_path) {
> +		ret = pm_runtime_force_resume(dev);
> +		if (ret < 0)
> +			return ret;
> +		pinctrl_pm_select_default_state(dev);
> +
> +		ret = stm32f7_i2c_regs_restore(i2c_dev);
> +		if (ret < 0)
> +			return ret;
> +	}
>  
> -	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,
>
Wolfram Sang Feb. 22, 2020, 12:34 p.m. UTC | #2
On Mon, Feb 03, 2020 at 06:52:08PM +0100, Alain Volmat wrote:
> 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: Alain Volmat <alain.volmat@st.com>

Applied to for-next, thanks!
diff mbox series

Patch

diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c
index 5c3e8ac6ad92..378956ac6d1d 100644
--- a/drivers/i2c/busses/i2c-stm32f7.c
+++ b/drivers/i2c/busses/i2c-stm32f7.c
@@ -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 @@  static int stm32f7_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
 	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 @@  static int stm32f7_i2c_probe(struct platform_device *pdev)
 	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;
@@ -2127,41 +2185,48 @@  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);
-	ret = stm32f7_i2c_regs_backup(i2c_dev);
-	if (ret < 0) {
-		i2c_mark_adapter_resumed(&i2c_dev->adap);
-		return ret;
-	}
 
-	pinctrl_pm_select_sleep_state(dev);
-	pm_runtime_force_suspend(dev);
+	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);
+			return ret;
+		}
+
+		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;
 
-	ret = pm_runtime_force_resume(dev);
-	if (ret < 0)
-		return ret;
-	pinctrl_pm_select_default_state(dev);
+	if (!device_may_wakeup(dev) && !dev->power.wakeup_path) {
+		ret = pm_runtime_force_resume(dev);
+		if (ret < 0)
+			return ret;
+		pinctrl_pm_select_default_state(dev);
+
+		ret = stm32f7_i2c_regs_restore(i2c_dev);
+		if (ret < 0)
+			return ret;
+	}
 
-	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,