From 4e7bca6fc07bf9526d797b9787dcb21e40cd10cf Mon Sep 17 00:00:00 2001 From: Pierre-Yves MORDRET Date: Tue, 27 Nov 2018 15:35:31 +0100 Subject: i2c: i2c-stm32f7: add PM Runtime support Use PM Runtime API to enable/disable clock Signed-off-by: Pierre-Yves MORDRET Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-stm32f7.c | 144 +++++++++++++++++++++++++++------------ 1 file changed, 101 insertions(+), 43 deletions(-) (limited to 'drivers/i2c') diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c index e9f0c0bd774d..13e1213561d4 100644 --- a/drivers/i2c/busses/i2c-stm32f7.c +++ b/drivers/i2c/busses/i2c-stm32f7.c @@ -28,6 +28,8 @@ #include #include #include +#include +#include #include #include #include @@ -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"); - return ret; - } - } + 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, -- cgit v1.2.3