diff options
Diffstat (limited to 'drivers/iio/adc/exynos_adc.c')
-rw-r--r-- | drivers/iio/adc/exynos_adc.c | 131 |
1 files changed, 71 insertions, 60 deletions
diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c index affa93f51789..010578f1d762 100644 --- a/drivers/iio/adc/exynos_adc.c +++ b/drivers/iio/adc/exynos_adc.c @@ -82,7 +82,7 @@ enum adc_version { #define ADC_CON_EN_START (1u << 0) #define ADC_DATX_MASK 0xFFF -#define EXYNOS_ADC_TIMEOUT (msecs_to_jiffies(1000)) +#define EXYNOS_ADC_TIMEOUT (msecs_to_jiffies(100)) struct exynos_adc { void __iomem *regs; @@ -112,6 +112,30 @@ static inline unsigned int exynos_adc_get_version(struct platform_device *pdev) return (unsigned int)match->data; } +static void exynos_adc_hw_init(struct exynos_adc *info) +{ + u32 con1, con2; + + if (info->version == ADC_V2) { + con1 = ADC_V2_CON1_SOFT_RESET; + writel(con1, ADC_V2_CON1(info->regs)); + + con2 = ADC_V2_CON2_OSEL | ADC_V2_CON2_ESEL | + ADC_V2_CON2_HIGHF | ADC_V2_CON2_C_TIME(0); + writel(con2, ADC_V2_CON2(info->regs)); + + /* Enable interrupts */ + writel(1, ADC_V2_INT_EN(info->regs)); + } else { + /* set default prescaler values and Enable prescaler */ + con1 = ADC_V1_CON_PRSCLV(49) | ADC_V1_CON_PRSCEN; + + /* Enable 12-bit ADC resolution */ + con1 |= ADC_V1_CON_RES; + writel(con1, ADC_V1_CON(info->regs)); + } +} + static int exynos_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, @@ -121,11 +145,13 @@ static int exynos_read_raw(struct iio_dev *indio_dev, struct exynos_adc *info = iio_priv(indio_dev); unsigned long timeout; u32 con1, con2; + int ret; if (mask != IIO_CHAN_INFO_RAW) return -EINVAL; mutex_lock(&indio_dev->mlock); + reinit_completion(&info->completion); /* Select the channel to be used and Trigger conversion */ if (info->version == ADC_V2) { @@ -145,16 +171,21 @@ static int exynos_read_raw(struct iio_dev *indio_dev, ADC_V1_CON(info->regs)); } - timeout = wait_for_completion_interruptible_timeout + timeout = wait_for_completion_timeout (&info->completion, EXYNOS_ADC_TIMEOUT); - *val = info->value; + if (timeout == 0) { + dev_warn(&indio_dev->dev, "Conversion timed out! Resetting\n"); + exynos_adc_hw_init(info); + ret = -ETIMEDOUT; + } else { + *val = info->value; + *val2 = 0; + ret = IIO_VAL_INT; + } mutex_unlock(&indio_dev->mlock); - if (timeout == 0) - return -ETIMEDOUT; - - return IIO_VAL_INT; + return ret; } static irqreturn_t exynos_adc_isr(int irq, void *dev_id) @@ -226,30 +257,6 @@ static int exynos_adc_remove_devices(struct device *dev, void *c) return 0; } -static void exynos_adc_hw_init(struct exynos_adc *info) -{ - u32 con1, con2; - - if (info->version == ADC_V2) { - con1 = ADC_V2_CON1_SOFT_RESET; - writel(con1, ADC_V2_CON1(info->regs)); - - con2 = ADC_V2_CON2_OSEL | ADC_V2_CON2_ESEL | - ADC_V2_CON2_HIGHF | ADC_V2_CON2_C_TIME(0); - writel(con2, ADC_V2_CON2(info->regs)); - - /* Enable interrupts */ - writel(1, ADC_V2_INT_EN(info->regs)); - } else { - /* set default prescaler values and Enable prescaler */ - con1 = ADC_V1_CON_PRSCLV(49) | ADC_V1_CON_PRSCEN; - - /* Enable 12-bit ADC resolution */ - con1 |= ADC_V1_CON_RES; - writel(con1, ADC_V1_CON(info->regs)); - } -} - static int exynos_adc_probe(struct platform_device *pdev) { struct exynos_adc *info = NULL; @@ -290,32 +297,30 @@ static int exynos_adc_probe(struct platform_device *pdev) init_completion(&info->completion); - ret = request_irq(info->irq, exynos_adc_isr, - 0, dev_name(&pdev->dev), info); - if (ret < 0) { - dev_err(&pdev->dev, "failed requesting irq, irq = %d\n", - info->irq); - return ret; - } - - writel(1, info->enable_reg); - info->clk = devm_clk_get(&pdev->dev, "adc"); if (IS_ERR(info->clk)) { dev_err(&pdev->dev, "failed getting clock, err = %ld\n", PTR_ERR(info->clk)); - ret = PTR_ERR(info->clk); - goto err_irq; + return PTR_ERR(info->clk); } info->vdd = devm_regulator_get(&pdev->dev, "vdd"); if (IS_ERR(info->vdd)) { dev_err(&pdev->dev, "failed getting regulator, err = %ld\n", PTR_ERR(info->vdd)); - ret = PTR_ERR(info->vdd); - goto err_irq; + return PTR_ERR(info->vdd); } + ret = regulator_enable(info->vdd); + if (ret) + return ret; + + ret = clk_prepare_enable(info->clk); + if (ret) + goto err_disable_reg; + + writel(1, info->enable_reg); + info->version = exynos_adc_get_version(pdev); platform_set_drvdata(pdev, indio_dev); @@ -332,16 +337,18 @@ static int exynos_adc_probe(struct platform_device *pdev) else indio_dev->num_channels = MAX_ADC_V2_CHANNELS; + ret = request_irq(info->irq, exynos_adc_isr, + 0, dev_name(&pdev->dev), info); + if (ret < 0) { + dev_err(&pdev->dev, "failed requesting irq, irq = %d\n", + info->irq); + goto err_disable_clk; + } + ret = iio_device_register(indio_dev); if (ret) goto err_irq; - ret = regulator_enable(info->vdd); - if (ret) - goto err_iio_dev; - - clk_prepare_enable(info->clk); - exynos_adc_hw_init(info); ret = of_platform_populate(np, exynos_adc_match, NULL, &indio_dev->dev); @@ -355,12 +362,14 @@ static int exynos_adc_probe(struct platform_device *pdev) err_of_populate: device_for_each_child(&indio_dev->dev, NULL, exynos_adc_remove_devices); - regulator_disable(info->vdd); - clk_disable_unprepare(info->clk); -err_iio_dev: iio_device_unregister(indio_dev); err_irq: free_irq(info->irq, info); +err_disable_clk: + writel(0, info->enable_reg); + clk_disable_unprepare(info->clk); +err_disable_reg: + regulator_disable(info->vdd); return ret; } @@ -371,11 +380,11 @@ static int exynos_adc_remove(struct platform_device *pdev) device_for_each_child(&indio_dev->dev, NULL, exynos_adc_remove_devices); - regulator_disable(info->vdd); - clk_disable_unprepare(info->clk); - writel(0, info->enable_reg); iio_device_unregister(indio_dev); free_irq(info->irq, info); + writel(0, info->enable_reg); + clk_disable_unprepare(info->clk); + regulator_disable(info->vdd); return 0; } @@ -397,8 +406,8 @@ static int exynos_adc_suspend(struct device *dev) writel(con, ADC_V1_CON(info->regs)); } - clk_disable_unprepare(info->clk); writel(0, info->enable_reg); + clk_disable_unprepare(info->clk); regulator_disable(info->vdd); return 0; @@ -414,9 +423,11 @@ static int exynos_adc_resume(struct device *dev) if (ret) return ret; - writel(1, info->enable_reg); - clk_prepare_enable(info->clk); + ret = clk_prepare_enable(info->clk); + if (ret) + return ret; + writel(1, info->enable_reg); exynos_adc_hw_init(info); return 0; |