From 03dd4cb26d967f9588437b0fc9cc0e8353322bb7 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Fabian=20Silva=20Delgado?= Date: Fri, 25 Mar 2016 03:53:42 -0300 Subject: Linux-libre 4.5-gnu --- drivers/iio/adc/imx7d_adc.c | 609 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 609 insertions(+) create mode 100644 drivers/iio/adc/imx7d_adc.c (limited to 'drivers/iio/adc/imx7d_adc.c') diff --git a/drivers/iio/adc/imx7d_adc.c b/drivers/iio/adc/imx7d_adc.c new file mode 100644 index 000000000..e2241ee94 --- /dev/null +++ b/drivers/iio/adc/imx7d_adc.c @@ -0,0 +1,609 @@ +/* + * Freescale i.MX7D ADC driver + * + * Copyright (C) 2015 Freescale Semiconductor, Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +/* ADC register */ +#define IMX7D_REG_ADC_CH_A_CFG1 0x00 +#define IMX7D_REG_ADC_CH_A_CFG2 0x10 +#define IMX7D_REG_ADC_CH_B_CFG1 0x20 +#define IMX7D_REG_ADC_CH_B_CFG2 0x30 +#define IMX7D_REG_ADC_CH_C_CFG1 0x40 +#define IMX7D_REG_ADC_CH_C_CFG2 0x50 +#define IMX7D_REG_ADC_CH_D_CFG1 0x60 +#define IMX7D_REG_ADC_CH_D_CFG2 0x70 +#define IMX7D_REG_ADC_CH_SW_CFG 0x80 +#define IMX7D_REG_ADC_TIMER_UNIT 0x90 +#define IMX7D_REG_ADC_DMA_FIFO 0xa0 +#define IMX7D_REG_ADC_FIFO_STATUS 0xb0 +#define IMX7D_REG_ADC_INT_SIG_EN 0xc0 +#define IMX7D_REG_ADC_INT_EN 0xd0 +#define IMX7D_REG_ADC_INT_STATUS 0xe0 +#define IMX7D_REG_ADC_CHA_B_CNV_RSLT 0xf0 +#define IMX7D_REG_ADC_CHC_D_CNV_RSLT 0x100 +#define IMX7D_REG_ADC_CH_SW_CNV_RSLT 0x110 +#define IMX7D_REG_ADC_DMA_FIFO_DAT 0x120 +#define IMX7D_REG_ADC_ADC_CFG 0x130 + +#define IMX7D_REG_ADC_CHANNEL_CFG2_BASE 0x10 +#define IMX7D_EACH_CHANNEL_REG_OFFSET 0x20 + +#define IMX7D_REG_ADC_CH_CFG1_CHANNEL_EN (0x1 << 31) +#define IMX7D_REG_ADC_CH_CFG1_CHANNEL_SINGLE BIT(30) +#define IMX7D_REG_ADC_CH_CFG1_CHANNEL_AVG_EN BIT(29) +#define IMX7D_REG_ADC_CH_CFG1_CHANNEL_SEL(x) ((x) << 24) + +#define IMX7D_REG_ADC_CH_CFG2_AVG_NUM_4 (0x0 << 12) +#define IMX7D_REG_ADC_CH_CFG2_AVG_NUM_8 (0x1 << 12) +#define IMX7D_REG_ADC_CH_CFG2_AVG_NUM_16 (0x2 << 12) +#define IMX7D_REG_ADC_CH_CFG2_AVG_NUM_32 (0x3 << 12) + +#define IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_4 (0x0 << 29) +#define IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_8 (0x1 << 29) +#define IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_16 (0x2 << 29) +#define IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_32 (0x3 << 29) +#define IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_64 (0x4 << 29) +#define IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_128 (0x5 << 29) + +#define IMX7D_REG_ADC_ADC_CFG_ADC_CLK_DOWN BIT(31) +#define IMX7D_REG_ADC_ADC_CFG_ADC_POWER_DOWN BIT(1) +#define IMX7D_REG_ADC_ADC_CFG_ADC_EN BIT(0) + +#define IMX7D_REG_ADC_INT_CHA_COV_INT_EN BIT(8) +#define IMX7D_REG_ADC_INT_CHB_COV_INT_EN BIT(9) +#define IMX7D_REG_ADC_INT_CHC_COV_INT_EN BIT(10) +#define IMX7D_REG_ADC_INT_CHD_COV_INT_EN BIT(11) +#define IMX7D_REG_ADC_INT_CHANNEL_INT_EN \ + (IMX7D_REG_ADC_INT_CHA_COV_INT_EN | \ + IMX7D_REG_ADC_INT_CHB_COV_INT_EN | \ + IMX7D_REG_ADC_INT_CHC_COV_INT_EN | \ + IMX7D_REG_ADC_INT_CHD_COV_INT_EN) +#define IMX7D_REG_ADC_INT_STATUS_CHANNEL_INT_STATUS 0xf00 +#define IMX7D_REG_ADC_INT_STATUS_CHANNEL_CONV_TIME_OUT 0xf0000 + +#define IMX7D_ADC_TIMEOUT msecs_to_jiffies(100) + +enum imx7d_adc_clk_pre_div { + IMX7D_ADC_ANALOG_CLK_PRE_DIV_4, + IMX7D_ADC_ANALOG_CLK_PRE_DIV_8, + IMX7D_ADC_ANALOG_CLK_PRE_DIV_16, + IMX7D_ADC_ANALOG_CLK_PRE_DIV_32, + IMX7D_ADC_ANALOG_CLK_PRE_DIV_64, + IMX7D_ADC_ANALOG_CLK_PRE_DIV_128, +}; + +enum imx7d_adc_average_num { + IMX7D_ADC_AVERAGE_NUM_4, + IMX7D_ADC_AVERAGE_NUM_8, + IMX7D_ADC_AVERAGE_NUM_16, + IMX7D_ADC_AVERAGE_NUM_32, +}; + +struct imx7d_adc_feature { + enum imx7d_adc_clk_pre_div clk_pre_div; + enum imx7d_adc_average_num avg_num; + + u32 core_time_unit; /* impact the sample rate */ + + bool average_en; +}; + +struct imx7d_adc { + struct device *dev; + void __iomem *regs; + struct clk *clk; + + u32 vref_uv; + u32 value; + u32 channel; + u32 pre_div_num; + + struct regulator *vref; + struct imx7d_adc_feature adc_feature; + + struct completion completion; +}; + +struct imx7d_adc_analogue_core_clk { + u32 pre_div; + u32 reg_config; +}; + +#define IMX7D_ADC_ANALOGUE_CLK_CONFIG(_pre_div, _reg_conf) { \ + .pre_div = (_pre_div), \ + .reg_config = (_reg_conf), \ +} + +static const struct imx7d_adc_analogue_core_clk imx7d_adc_analogue_clk[] = { + IMX7D_ADC_ANALOGUE_CLK_CONFIG(4, IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_4), + IMX7D_ADC_ANALOGUE_CLK_CONFIG(8, IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_8), + IMX7D_ADC_ANALOGUE_CLK_CONFIG(16, IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_16), + IMX7D_ADC_ANALOGUE_CLK_CONFIG(32, IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_32), + IMX7D_ADC_ANALOGUE_CLK_CONFIG(64, IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_64), + IMX7D_ADC_ANALOGUE_CLK_CONFIG(128, IMX7D_REG_ADC_TIMER_UNIT_PRE_DIV_128), +}; + +#define IMX7D_ADC_CHAN(_idx) { \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .channel = (_idx), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_SAMP_FREQ), \ +} + +static const struct iio_chan_spec imx7d_adc_iio_channels[] = { + IMX7D_ADC_CHAN(0), + IMX7D_ADC_CHAN(1), + IMX7D_ADC_CHAN(2), + IMX7D_ADC_CHAN(3), + IMX7D_ADC_CHAN(4), + IMX7D_ADC_CHAN(5), + IMX7D_ADC_CHAN(6), + IMX7D_ADC_CHAN(7), + IMX7D_ADC_CHAN(8), + IMX7D_ADC_CHAN(9), + IMX7D_ADC_CHAN(10), + IMX7D_ADC_CHAN(11), + IMX7D_ADC_CHAN(12), + IMX7D_ADC_CHAN(13), + IMX7D_ADC_CHAN(14), + IMX7D_ADC_CHAN(15), +}; + +static const u32 imx7d_adc_average_num[] = { + IMX7D_REG_ADC_CH_CFG2_AVG_NUM_4, + IMX7D_REG_ADC_CH_CFG2_AVG_NUM_8, + IMX7D_REG_ADC_CH_CFG2_AVG_NUM_16, + IMX7D_REG_ADC_CH_CFG2_AVG_NUM_32, +}; + +static void imx7d_adc_feature_config(struct imx7d_adc *info) +{ + info->adc_feature.clk_pre_div = IMX7D_ADC_ANALOG_CLK_PRE_DIV_4; + info->adc_feature.avg_num = IMX7D_ADC_AVERAGE_NUM_32; + info->adc_feature.core_time_unit = 1; + info->adc_feature.average_en = true; +} + +static void imx7d_adc_sample_rate_set(struct imx7d_adc *info) +{ + struct imx7d_adc_feature *adc_feature = &info->adc_feature; + struct imx7d_adc_analogue_core_clk adc_analogure_clk; + u32 i; + u32 tmp_cfg1; + u32 sample_rate = 0; + + /* + * Before sample set, disable channel A,B,C,D. Here we + * clear the bit 31 of register REG_ADC_CH_A\B\C\D_CFG1. + */ + for (i = 0; i < 4; i++) { + tmp_cfg1 = + readl(info->regs + i * IMX7D_EACH_CHANNEL_REG_OFFSET); + tmp_cfg1 &= ~IMX7D_REG_ADC_CH_CFG1_CHANNEL_EN; + writel(tmp_cfg1, + info->regs + i * IMX7D_EACH_CHANNEL_REG_OFFSET); + } + + adc_analogure_clk = imx7d_adc_analogue_clk[adc_feature->clk_pre_div]; + sample_rate |= adc_analogure_clk.reg_config; + info->pre_div_num = adc_analogure_clk.pre_div; + + sample_rate |= adc_feature->core_time_unit; + writel(sample_rate, info->regs + IMX7D_REG_ADC_TIMER_UNIT); +} + +static void imx7d_adc_hw_init(struct imx7d_adc *info) +{ + u32 cfg; + + /* power up and enable adc analogue core */ + cfg = readl(info->regs + IMX7D_REG_ADC_ADC_CFG); + cfg &= ~(IMX7D_REG_ADC_ADC_CFG_ADC_CLK_DOWN | + IMX7D_REG_ADC_ADC_CFG_ADC_POWER_DOWN); + cfg |= IMX7D_REG_ADC_ADC_CFG_ADC_EN; + writel(cfg, info->regs + IMX7D_REG_ADC_ADC_CFG); + + /* enable channel A,B,C,D interrupt */ + writel(IMX7D_REG_ADC_INT_CHANNEL_INT_EN, + info->regs + IMX7D_REG_ADC_INT_SIG_EN); + writel(IMX7D_REG_ADC_INT_CHANNEL_INT_EN, + info->regs + IMX7D_REG_ADC_INT_EN); + + imx7d_adc_sample_rate_set(info); +} + +static void imx7d_adc_channel_set(struct imx7d_adc *info) +{ + u32 cfg1 = 0; + u32 cfg2; + u32 channel; + + channel = info->channel; + + /* the channel choose single conversion, and enable average mode */ + cfg1 |= (IMX7D_REG_ADC_CH_CFG1_CHANNEL_EN | + IMX7D_REG_ADC_CH_CFG1_CHANNEL_SINGLE); + if (info->adc_feature.average_en) + cfg1 |= IMX7D_REG_ADC_CH_CFG1_CHANNEL_AVG_EN; + + /* + * physical channel 0 chose logical channel A + * physical channel 1 chose logical channel B + * physical channel 2 chose logical channel C + * physical channel 3 chose logical channel D + */ + cfg1 |= IMX7D_REG_ADC_CH_CFG1_CHANNEL_SEL(channel); + + /* + * read register REG_ADC_CH_A\B\C\D_CFG2, according to the + * channel chosen + */ + cfg2 = readl(info->regs + IMX7D_EACH_CHANNEL_REG_OFFSET * channel + + IMX7D_REG_ADC_CHANNEL_CFG2_BASE); + + cfg2 |= imx7d_adc_average_num[info->adc_feature.avg_num]; + + /* + * write the register REG_ADC_CH_A\B\C\D_CFG2, according to + * the channel chosen + */ + writel(cfg2, info->regs + IMX7D_EACH_CHANNEL_REG_OFFSET * channel + + IMX7D_REG_ADC_CHANNEL_CFG2_BASE); + writel(cfg1, info->regs + IMX7D_EACH_CHANNEL_REG_OFFSET * channel); +} + +static u32 imx7d_adc_get_sample_rate(struct imx7d_adc *info) +{ + /* input clock is always 24MHz */ + u32 input_clk = 24000000; + u32 analogue_core_clk; + u32 core_time_unit = info->adc_feature.core_time_unit; + u32 tmp; + + analogue_core_clk = input_clk / info->pre_div_num; + tmp = (core_time_unit + 1) * 6; + + return analogue_core_clk / tmp; +} + +static int imx7d_adc_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, + int *val2, + long mask) +{ + struct imx7d_adc *info = iio_priv(indio_dev); + + u32 channel; + long ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + mutex_lock(&indio_dev->mlock); + reinit_completion(&info->completion); + + channel = chan->channel & 0x03; + info->channel = channel; + imx7d_adc_channel_set(info); + + ret = wait_for_completion_interruptible_timeout + (&info->completion, IMX7D_ADC_TIMEOUT); + if (ret == 0) { + mutex_unlock(&indio_dev->mlock); + return -ETIMEDOUT; + } + if (ret < 0) { + mutex_unlock(&indio_dev->mlock); + return ret; + } + + *val = info->value; + mutex_unlock(&indio_dev->mlock); + return IIO_VAL_INT; + + case IIO_CHAN_INFO_SCALE: + info->vref_uv = regulator_get_voltage(info->vref); + *val = info->vref_uv / 1000; + *val2 = 12; + return IIO_VAL_FRACTIONAL_LOG2; + + case IIO_CHAN_INFO_SAMP_FREQ: + *val = imx7d_adc_get_sample_rate(info); + return IIO_VAL_INT; + + default: + return -EINVAL; + } +} + +static int imx7d_adc_read_data(struct imx7d_adc *info) +{ + u32 channel; + u32 value; + + channel = info->channel & 0x03; + + /* + * channel A and B conversion result share one register, + * bit[27~16] is the channel B conversion result, + * bit[11~0] is the channel A conversion result. + * channel C and D is the same. + */ + if (channel < 2) + value = readl(info->regs + IMX7D_REG_ADC_CHA_B_CNV_RSLT); + else + value = readl(info->regs + IMX7D_REG_ADC_CHC_D_CNV_RSLT); + if (channel & 0x1) /* channel B or D */ + value = (value >> 16) & 0xFFF; + else /* channel A or C */ + value &= 0xFFF; + + return value; +} + +static irqreturn_t imx7d_adc_isr(int irq, void *dev_id) +{ + struct imx7d_adc *info = (struct imx7d_adc *)dev_id; + int status; + + status = readl(info->regs + IMX7D_REG_ADC_INT_STATUS); + if (status & IMX7D_REG_ADC_INT_STATUS_CHANNEL_INT_STATUS) { + info->value = imx7d_adc_read_data(info); + complete(&info->completion); + + /* + * The register IMX7D_REG_ADC_INT_STATUS can't clear + * itself after read operation, need software to write + * 0 to the related bit. Here we clear the channel A/B/C/D + * conversion finished flag. + */ + status &= ~IMX7D_REG_ADC_INT_STATUS_CHANNEL_INT_STATUS; + writel(status, info->regs + IMX7D_REG_ADC_INT_STATUS); + } + + /* + * If the channel A/B/C/D conversion timeout, report it and clear these + * timeout flags. + */ + if (status & IMX7D_REG_ADC_INT_STATUS_CHANNEL_CONV_TIME_OUT) { + pr_err("%s: ADC got conversion time out interrupt: 0x%08x\n", + dev_name(info->dev), status); + status &= ~IMX7D_REG_ADC_INT_STATUS_CHANNEL_CONV_TIME_OUT; + writel(status, info->regs + IMX7D_REG_ADC_INT_STATUS); + } + + return IRQ_HANDLED; +} + +static int imx7d_adc_reg_access(struct iio_dev *indio_dev, + unsigned reg, unsigned writeval, + unsigned *readval) +{ + struct imx7d_adc *info = iio_priv(indio_dev); + + if (!readval || reg % 4 || reg > IMX7D_REG_ADC_ADC_CFG) + return -EINVAL; + + *readval = readl(info->regs + reg); + + return 0; +} + +static const struct iio_info imx7d_adc_iio_info = { + .driver_module = THIS_MODULE, + .read_raw = &imx7d_adc_read_raw, + .debugfs_reg_access = &imx7d_adc_reg_access, +}; + +static const struct of_device_id imx7d_adc_match[] = { + { .compatible = "fsl,imx7d-adc", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, imx7d_adc_match); + +static void imx7d_adc_power_down(struct imx7d_adc *info) +{ + u32 adc_cfg; + + adc_cfg = readl(info->regs + IMX7D_REG_ADC_ADC_CFG); + adc_cfg |= IMX7D_REG_ADC_ADC_CFG_ADC_CLK_DOWN | + IMX7D_REG_ADC_ADC_CFG_ADC_POWER_DOWN; + adc_cfg &= ~IMX7D_REG_ADC_ADC_CFG_ADC_EN; + writel(adc_cfg, info->regs + IMX7D_REG_ADC_ADC_CFG); +} + +static int imx7d_adc_probe(struct platform_device *pdev) +{ + struct imx7d_adc *info; + struct iio_dev *indio_dev; + struct resource *mem; + int irq; + int ret; + + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info)); + if (!indio_dev) { + dev_err(&pdev->dev, "Failed allocating iio device\n"); + return -ENOMEM; + } + + info = iio_priv(indio_dev); + info->dev = &pdev->dev; + + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + info->regs = devm_ioremap_resource(&pdev->dev, mem); + if (IS_ERR(info->regs)) { + ret = PTR_ERR(info->regs); + dev_err(&pdev->dev, + "Failed to remap adc memory, err = %d\n", ret); + return ret; + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(&pdev->dev, "No irq resource?\n"); + return irq; + } + + info->clk = devm_clk_get(&pdev->dev, "adc"); + if (IS_ERR(info->clk)) { + ret = PTR_ERR(info->clk); + dev_err(&pdev->dev, "Failed getting clock, err = %d\n", ret); + return ret; + } + + info->vref = devm_regulator_get(&pdev->dev, "vref"); + if (IS_ERR(info->vref)) { + ret = PTR_ERR(info->vref); + dev_err(&pdev->dev, + "Failed getting reference voltage, err = %d\n", ret); + return ret; + } + + ret = regulator_enable(info->vref); + if (ret) { + dev_err(&pdev->dev, + "Can't enable adc reference top voltage, err = %d\n", + ret); + return ret; + } + + platform_set_drvdata(pdev, indio_dev); + + init_completion(&info->completion); + + indio_dev->name = dev_name(&pdev->dev); + indio_dev->dev.parent = &pdev->dev; + indio_dev->info = &imx7d_adc_iio_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = imx7d_adc_iio_channels; + indio_dev->num_channels = ARRAY_SIZE(imx7d_adc_iio_channels); + + ret = clk_prepare_enable(info->clk); + if (ret) { + dev_err(&pdev->dev, + "Could not prepare or enable the clock.\n"); + goto error_adc_clk_enable; + } + + ret = devm_request_irq(info->dev, irq, + imx7d_adc_isr, 0, + dev_name(&pdev->dev), info); + if (ret < 0) { + dev_err(&pdev->dev, "Failed requesting irq, irq = %d\n", irq); + goto error_iio_device_register; + } + + imx7d_adc_feature_config(info); + imx7d_adc_hw_init(info); + + ret = iio_device_register(indio_dev); + if (ret) { + imx7d_adc_power_down(info); + dev_err(&pdev->dev, "Couldn't register the device.\n"); + goto error_iio_device_register; + } + + return 0; + +error_iio_device_register: + clk_disable_unprepare(info->clk); +error_adc_clk_enable: + regulator_disable(info->vref); + + return ret; +} + +static int imx7d_adc_remove(struct platform_device *pdev) +{ + struct iio_dev *indio_dev = platform_get_drvdata(pdev); + struct imx7d_adc *info = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + + imx7d_adc_power_down(info); + + clk_disable_unprepare(info->clk); + regulator_disable(info->vref); + + return 0; +} + +static int __maybe_unused imx7d_adc_suspend(struct device *dev) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct imx7d_adc *info = iio_priv(indio_dev); + + imx7d_adc_power_down(info); + + clk_disable_unprepare(info->clk); + regulator_disable(info->vref); + + return 0; +} + +static int __maybe_unused imx7d_adc_resume(struct device *dev) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct imx7d_adc *info = iio_priv(indio_dev); + int ret; + + ret = regulator_enable(info->vref); + if (ret) { + dev_err(info->dev, + "Can't enable adc reference top voltage, err = %d\n", + ret); + return ret; + } + + ret = clk_prepare_enable(info->clk); + if (ret) { + dev_err(info->dev, + "Could not prepare or enable clock.\n"); + regulator_disable(info->vref); + return ret; + } + + imx7d_adc_hw_init(info); + + return 0; +} + +static SIMPLE_DEV_PM_OPS(imx7d_adc_pm_ops, imx7d_adc_suspend, imx7d_adc_resume); + +static struct platform_driver imx7d_adc_driver = { + .probe = imx7d_adc_probe, + .remove = imx7d_adc_remove, + .driver = { + .name = "imx7d_adc", + .of_match_table = imx7d_adc_match, + .pm = &imx7d_adc_pm_ops, + }, +}; + +module_platform_driver(imx7d_adc_driver); + +MODULE_AUTHOR("Haibo Chen "); +MODULE_DESCRIPTION("Freeacale IMX7D ADC driver"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3