From 2bbc7247259f0d27c84b0e0746bd5e9831e39c36 Mon Sep 17 00:00:00 2001 From: Naveen Krishna Ch Date: Wed, 30 Apr 2014 10:26:00 +0100 Subject: iio: exynos_adc: rearrange clk and regulator enable/disable calls This patch maintains the following order in probe(), remove(), resume() and suspend() calls regulator enable, clk prepare enable ... clk disable unprepare, regulator disable While at it, 1. enable the regulator before the iio_device_register() 2. handle the return values for enable/disable calls Signed-off-by: Naveen Krishna Ch Reviewed-by: Doug Anderson Signed-off-by: Jonathan Cameron --- drivers/iio/adc/exynos_adc.c | 62 +++++++++++++++++++++++--------------------- 1 file changed, 33 insertions(+), 29 deletions(-) (limited to 'drivers/iio/adc/exynos_adc.c') diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c index d25b262193a7..9d296094892d 100644 --- a/drivers/iio/adc/exynos_adc.c +++ b/drivers/iio/adc/exynos_adc.c @@ -290,32 +290,30 @@ 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 +330,18 @@ 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, &pdev->dev); @@ -355,12 +355,14 @@ static int exynos_adc_probe(struct platform_device *pdev) err_of_populate: device_for_each_child(&pdev->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 +373,11 @@ static int exynos_adc_remove(struct platform_device *pdev) device_for_each_child(&pdev->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 +399,8 @@ 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 +416,11 @@ 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; -- cgit From c780a8c2415b21514b0a8b5398d7167c93627c64 Mon Sep 17 00:00:00 2001 From: Naveen Krishna Chatradhi Date: Wed, 30 Apr 2014 10:26:00 +0100 Subject: iio: exynos_adc: reduce timeout and use wait_for_completion_timeout ADC module on Exynos5 SoCs runs at 600KSPS. At this conversion rate, waiting for 1000 msecs is wasteful (incase of h/w failure). Hence, reduce the time out to 100msecs and use wait_for_completion_timeout() instead of wait_for_completion_interruptible_timeout() Signed-off-by: Naveen Krishna Chatradhi Reviewed-by: Doug Anderson Signed-off-by: Jonathan Cameron --- drivers/iio/adc/exynos_adc.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) (limited to 'drivers/iio/adc/exynos_adc.c') diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c index 9d296094892d..a1f6d90f3d26 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; @@ -121,6 +121,7 @@ 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; @@ -145,16 +146,19 @@ 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) { + 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) -- cgit From dd2723f57e3cd8f104884636e92492b884080d59 Mon Sep 17 00:00:00 2001 From: Naveen Krishna Chatradhi Date: Wed, 30 Apr 2014 10:26:00 +0100 Subject: iio: exynos_adc: do a soft reset in case of timeout Do a soft reset software if a timeout happens. This is applicable only for ADC_V2. Signed-off-by: Naveen Krishna Chatradhi Reviewed-by: Doug Anderson Signed-off-by: Jonathan Cameron --- drivers/iio/adc/exynos_adc.c | 50 +++++++++++++++++++++++--------------------- 1 file changed, 26 insertions(+), 24 deletions(-) (limited to 'drivers/iio/adc/exynos_adc.c') diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c index a1f6d90f3d26..a9946ec7a3b7 100644 --- a/drivers/iio/adc/exynos_adc.c +++ b/drivers/iio/adc/exynos_adc.c @@ -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, @@ -149,6 +173,8 @@ static int exynos_read_raw(struct iio_dev *indio_dev, timeout = wait_for_completion_timeout (&info->completion, EXYNOS_ADC_TIMEOUT); if (timeout == 0) { + dev_warn(&indio_dev->dev, "Conversion timed out! Resetting\n"); + exynos_adc_hw_init(info); ret = -ETIMEDOUT; } else { *val = info->value; @@ -230,30 +256,6 @@ 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; -- cgit From 6442d94ba19da5424d670f4a4523be45e1ee78d9 Mon Sep 17 00:00:00 2001 From: Naveen Krishna Chatradhi Date: Wed, 30 Apr 2014 10:26:00 +0100 Subject: iio: exynos_adc: do a reinit_completion before the conversion Add reinit_completion() before the wait_for_completion_timeout in raw_read() call. Signed-off-by: Naveen Krishna Chatradhi Reviewed-by: Doug Anderson Signed-off-by: Jonathan Cameron --- drivers/iio/adc/exynos_adc.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/iio/adc/exynos_adc.c') diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c index a9946ec7a3b7..d325aeafe5cb 100644 --- a/drivers/iio/adc/exynos_adc.c +++ b/drivers/iio/adc/exynos_adc.c @@ -151,6 +151,7 @@ static int exynos_read_raw(struct iio_dev *indio_dev, 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) { -- cgit