| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Copyright (C) 2014-2015 Pengutronix, Markus Pargmann <mpa@pengutronix.de> |
| * |
| * This is the driver for the imx25 GCQ (Generic Conversion Queue) |
| * connected to the imx25 ADC. |
| */ |
| |
| #include <dt-bindings/iio/adc/fsl-imx25-gcq.h> |
| #include <linux/clk.h> |
| #include <linux/iio/iio.h> |
| #include <linux/interrupt.h> |
| #include <linux/mfd/imx25-tsadc.h> |
| #include <linux/module.h> |
| #include <linux/of.h> |
| #include <linux/platform_device.h> |
| #include <linux/regmap.h> |
| #include <linux/regulator/consumer.h> |
| |
| #define MX25_GCQ_TIMEOUT (msecs_to_jiffies(2000)) |
| |
| static const char * const driver_name = "mx25-gcq"; |
| |
| enum mx25_gcq_cfgs { |
| MX25_CFG_XP = 0, |
| MX25_CFG_YP, |
| MX25_CFG_XN, |
| MX25_CFG_YN, |
| MX25_CFG_WIPER, |
| MX25_CFG_INAUX0, |
| MX25_CFG_INAUX1, |
| MX25_CFG_INAUX2, |
| MX25_NUM_CFGS, |
| }; |
| |
| struct mx25_gcq_priv { |
| struct regmap *regs; |
| struct completion completed; |
| struct clk *clk; |
| int irq; |
| struct regulator *vref[4]; |
| u32 channel_vref_mv[MX25_NUM_CFGS]; |
| }; |
| |
| #define MX25_CQG_CHAN(chan, id) {\ |
| .type = IIO_VOLTAGE,\ |
| .indexed = 1,\ |
| .channel = chan,\ |
| .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ |
| BIT(IIO_CHAN_INFO_SCALE),\ |
| .datasheet_name = id,\ |
| } |
| |
| static const struct iio_chan_spec mx25_gcq_channels[MX25_NUM_CFGS] = { |
| MX25_CQG_CHAN(MX25_CFG_XP, "xp"), |
| MX25_CQG_CHAN(MX25_CFG_YP, "yp"), |
| MX25_CQG_CHAN(MX25_CFG_XN, "xn"), |
| MX25_CQG_CHAN(MX25_CFG_YN, "yn"), |
| MX25_CQG_CHAN(MX25_CFG_WIPER, "wiper"), |
| MX25_CQG_CHAN(MX25_CFG_INAUX0, "inaux0"), |
| MX25_CQG_CHAN(MX25_CFG_INAUX1, "inaux1"), |
| MX25_CQG_CHAN(MX25_CFG_INAUX2, "inaux2"), |
| }; |
| |
| static const char * const mx25_gcq_refp_names[] = { |
| [MX25_ADC_REFP_YP] = "yp", |
| [MX25_ADC_REFP_XP] = "xp", |
| [MX25_ADC_REFP_INT] = "int", |
| [MX25_ADC_REFP_EXT] = "ext", |
| }; |
| |
| static irqreturn_t mx25_gcq_irq(int irq, void *data) |
| { |
| struct mx25_gcq_priv *priv = data; |
| u32 stats; |
| |
| regmap_read(priv->regs, MX25_ADCQ_SR, &stats); |
| |
| if (stats & MX25_ADCQ_SR_EOQ) { |
| regmap_update_bits(priv->regs, MX25_ADCQ_MR, |
| MX25_ADCQ_MR_EOQ_IRQ, MX25_ADCQ_MR_EOQ_IRQ); |
| complete(&priv->completed); |
| } |
| |
| /* Disable conversion queue run */ |
| regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_FQS, 0); |
| |
| /* Acknowledge all possible irqs */ |
| regmap_write(priv->regs, MX25_ADCQ_SR, MX25_ADCQ_SR_FRR | |
| MX25_ADCQ_SR_FUR | MX25_ADCQ_SR_FOR | |
| MX25_ADCQ_SR_EOQ | MX25_ADCQ_SR_PD); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static int mx25_gcq_get_raw_value(struct device *dev, |
| struct iio_chan_spec const *chan, |
| struct mx25_gcq_priv *priv, |
| int *val) |
| { |
| long timeout; |
| u32 data; |
| |
| /* Setup the configuration we want to use */ |
| regmap_write(priv->regs, MX25_ADCQ_ITEM_7_0, |
| MX25_ADCQ_ITEM(0, chan->channel)); |
| |
| regmap_update_bits(priv->regs, MX25_ADCQ_MR, MX25_ADCQ_MR_EOQ_IRQ, 0); |
| |
| /* Trigger queue for one run */ |
| regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_FQS, |
| MX25_ADCQ_CR_FQS); |
| |
| timeout = wait_for_completion_interruptible_timeout( |
| &priv->completed, MX25_GCQ_TIMEOUT); |
| if (timeout < 0) { |
| dev_err(dev, "ADC wait for measurement failed\n"); |
| return timeout; |
| } else if (timeout == 0) { |
| dev_err(dev, "ADC timed out\n"); |
| return -ETIMEDOUT; |
| } |
| |
| regmap_read(priv->regs, MX25_ADCQ_FIFO, &data); |
| |
| *val = MX25_ADCQ_FIFO_DATA(data); |
| |
| return IIO_VAL_INT; |
| } |
| |
| static int mx25_gcq_read_raw(struct iio_dev *indio_dev, |
| struct iio_chan_spec const *chan, int *val, |
| int *val2, long mask) |
| { |
| struct mx25_gcq_priv *priv = iio_priv(indio_dev); |
| int ret; |
| |
| switch (mask) { |
| case IIO_CHAN_INFO_RAW: |
| mutex_lock(&indio_dev->mlock); |
| ret = mx25_gcq_get_raw_value(&indio_dev->dev, chan, priv, val); |
| mutex_unlock(&indio_dev->mlock); |
| return ret; |
| |
| case IIO_CHAN_INFO_SCALE: |
| *val = priv->channel_vref_mv[chan->channel]; |
| *val2 = 12; |
| return IIO_VAL_FRACTIONAL_LOG2; |
| |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| static const struct iio_info mx25_gcq_iio_info = { |
| .read_raw = mx25_gcq_read_raw, |
| }; |
| |
| static const struct regmap_config mx25_gcq_regconfig = { |
| .max_register = 0x5c, |
| .reg_bits = 32, |
| .val_bits = 32, |
| .reg_stride = 4, |
| }; |
| |
| static int mx25_gcq_setup_cfgs(struct platform_device *pdev, |
| struct mx25_gcq_priv *priv) |
| { |
| struct device_node *np = pdev->dev.of_node; |
| struct device_node *child; |
| struct device *dev = &pdev->dev; |
| unsigned int refp_used[4] = {}; |
| int ret, i; |
| |
| /* |
| * Setup all configurations registers with a default conversion |
| * configuration for each input |
| */ |
| for (i = 0; i < MX25_NUM_CFGS; ++i) |
| regmap_write(priv->regs, MX25_ADCQ_CFG(i), |
| MX25_ADCQ_CFG_YPLL_OFF | |
| MX25_ADCQ_CFG_XNUR_OFF | |
| MX25_ADCQ_CFG_XPUL_OFF | |
| MX25_ADCQ_CFG_REFP_INT | |
| MX25_ADCQ_CFG_IN(i) | |
| MX25_ADCQ_CFG_REFN_NGND2); |
| |
| /* |
| * First get all regulators to store them in channel_vref_mv if |
| * necessary. Later we use that information for proper IIO scale |
| * information. |
| */ |
| priv->vref[MX25_ADC_REFP_INT] = NULL; |
| priv->vref[MX25_ADC_REFP_EXT] = |
| devm_regulator_get_optional(&pdev->dev, "vref-ext"); |
| priv->vref[MX25_ADC_REFP_XP] = |
| devm_regulator_get_optional(&pdev->dev, "vref-xp"); |
| priv->vref[MX25_ADC_REFP_YP] = |
| devm_regulator_get_optional(&pdev->dev, "vref-yp"); |
| |
| for_each_child_of_node(np, child) { |
| u32 reg; |
| u32 refp = MX25_ADCQ_CFG_REFP_INT; |
| u32 refn = MX25_ADCQ_CFG_REFN_NGND2; |
| |
| ret = of_property_read_u32(child, "reg", ®); |
| if (ret) { |
| dev_err(dev, "Failed to get reg property\n"); |
| of_node_put(child); |
| return ret; |
| } |
| |
| if (reg >= MX25_NUM_CFGS) { |
| dev_err(dev, |
| "reg value is greater than the number of available configuration registers\n"); |
| of_node_put(child); |
| return -EINVAL; |
| } |
| |
| of_property_read_u32(child, "fsl,adc-refp", &refp); |
| of_property_read_u32(child, "fsl,adc-refn", &refn); |
| |
| switch (refp) { |
| case MX25_ADC_REFP_EXT: |
| case MX25_ADC_REFP_XP: |
| case MX25_ADC_REFP_YP: |
| if (IS_ERR(priv->vref[refp])) { |
| dev_err(dev, "Error, trying to use external voltage reference without a vref-%s regulator.", |
| mx25_gcq_refp_names[refp]); |
| of_node_put(child); |
| return PTR_ERR(priv->vref[refp]); |
| } |
| priv->channel_vref_mv[reg] = |
| regulator_get_voltage(priv->vref[refp]); |
| /* Conversion from uV to mV */ |
| priv->channel_vref_mv[reg] /= 1000; |
| break; |
| case MX25_ADC_REFP_INT: |
| priv->channel_vref_mv[reg] = 2500; |
| break; |
| default: |
| dev_err(dev, "Invalid positive reference %d\n", refp); |
| of_node_put(child); |
| return -EINVAL; |
| } |
| |
| ++refp_used[refp]; |
| |
| /* |
| * Shift the read values to the correct positions within the |
| * register. |
| */ |
| refp = MX25_ADCQ_CFG_REFP(refp); |
| refn = MX25_ADCQ_CFG_REFN(refn); |
| |
| if ((refp & MX25_ADCQ_CFG_REFP_MASK) != refp) { |
| dev_err(dev, "Invalid fsl,adc-refp property value\n"); |
| of_node_put(child); |
| return -EINVAL; |
| } |
| if ((refn & MX25_ADCQ_CFG_REFN_MASK) != refn) { |
| dev_err(dev, "Invalid fsl,adc-refn property value\n"); |
| of_node_put(child); |
| return -EINVAL; |
| } |
| |
| regmap_update_bits(priv->regs, MX25_ADCQ_CFG(reg), |
| MX25_ADCQ_CFG_REFP_MASK | |
| MX25_ADCQ_CFG_REFN_MASK, |
| refp | refn); |
| } |
| regmap_update_bits(priv->regs, MX25_ADCQ_CR, |
| MX25_ADCQ_CR_FRST | MX25_ADCQ_CR_QRST, |
| MX25_ADCQ_CR_FRST | MX25_ADCQ_CR_QRST); |
| |
| regmap_write(priv->regs, MX25_ADCQ_CR, |
| MX25_ADCQ_CR_PDMSK | MX25_ADCQ_CR_QSM_FQS); |
| |
| /* Remove unused regulators */ |
| for (i = 0; i != 4; ++i) { |
| if (!refp_used[i]) { |
| if (!IS_ERR_OR_NULL(priv->vref[i])) |
| devm_regulator_put(priv->vref[i]); |
| priv->vref[i] = NULL; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int mx25_gcq_probe(struct platform_device *pdev) |
| { |
| struct iio_dev *indio_dev; |
| struct mx25_gcq_priv *priv; |
| struct mx25_tsadc *tsadc = dev_get_drvdata(pdev->dev.parent); |
| struct device *dev = &pdev->dev; |
| struct resource *res; |
| void __iomem *mem; |
| int ret; |
| int i; |
| |
| indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*priv)); |
| if (!indio_dev) |
| return -ENOMEM; |
| |
| priv = iio_priv(indio_dev); |
| |
| res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| mem = devm_ioremap_resource(dev, res); |
| if (IS_ERR(mem)) |
| return PTR_ERR(mem); |
| |
| priv->regs = devm_regmap_init_mmio(dev, mem, &mx25_gcq_regconfig); |
| if (IS_ERR(priv->regs)) { |
| dev_err(dev, "Failed to initialize regmap\n"); |
| return PTR_ERR(priv->regs); |
| } |
| |
| init_completion(&priv->completed); |
| |
| ret = mx25_gcq_setup_cfgs(pdev, priv); |
| if (ret) |
| return ret; |
| |
| for (i = 0; i != 4; ++i) { |
| if (!priv->vref[i]) |
| continue; |
| |
| ret = regulator_enable(priv->vref[i]); |
| if (ret) |
| goto err_regulator_disable; |
| } |
| |
| priv->clk = tsadc->clk; |
| ret = clk_prepare_enable(priv->clk); |
| if (ret) { |
| dev_err(dev, "Failed to enable clock\n"); |
| goto err_vref_disable; |
| } |
| |
| priv->irq = platform_get_irq(pdev, 0); |
| if (priv->irq <= 0) { |
| ret = priv->irq; |
| if (!ret) |
| ret = -ENXIO; |
| goto err_clk_unprepare; |
| } |
| |
| ret = request_irq(priv->irq, mx25_gcq_irq, 0, pdev->name, priv); |
| if (ret) { |
| dev_err(dev, "Failed requesting IRQ\n"); |
| goto err_clk_unprepare; |
| } |
| |
| indio_dev->dev.parent = &pdev->dev; |
| indio_dev->channels = mx25_gcq_channels; |
| indio_dev->num_channels = ARRAY_SIZE(mx25_gcq_channels); |
| indio_dev->info = &mx25_gcq_iio_info; |
| indio_dev->name = driver_name; |
| |
| ret = iio_device_register(indio_dev); |
| if (ret) { |
| dev_err(dev, "Failed to register iio device\n"); |
| goto err_irq_free; |
| } |
| |
| platform_set_drvdata(pdev, indio_dev); |
| |
| return 0; |
| |
| err_irq_free: |
| free_irq(priv->irq, priv); |
| err_clk_unprepare: |
| clk_disable_unprepare(priv->clk); |
| err_vref_disable: |
| i = 4; |
| err_regulator_disable: |
| for (; i-- > 0;) { |
| if (priv->vref[i]) |
| regulator_disable(priv->vref[i]); |
| } |
| return ret; |
| } |
| |
| static int mx25_gcq_remove(struct platform_device *pdev) |
| { |
| struct iio_dev *indio_dev = platform_get_drvdata(pdev); |
| struct mx25_gcq_priv *priv = iio_priv(indio_dev); |
| int i; |
| |
| iio_device_unregister(indio_dev); |
| free_irq(priv->irq, priv); |
| clk_disable_unprepare(priv->clk); |
| for (i = 4; i-- > 0;) { |
| if (priv->vref[i]) |
| regulator_disable(priv->vref[i]); |
| } |
| |
| return 0; |
| } |
| |
| static const struct of_device_id mx25_gcq_ids[] = { |
| { .compatible = "fsl,imx25-gcq", }, |
| { /* Sentinel */ } |
| }; |
| MODULE_DEVICE_TABLE(of, mx25_gcq_ids); |
| |
| static struct platform_driver mx25_gcq_driver = { |
| .driver = { |
| .name = "mx25-gcq", |
| .of_match_table = mx25_gcq_ids, |
| }, |
| .probe = mx25_gcq_probe, |
| .remove = mx25_gcq_remove, |
| }; |
| module_platform_driver(mx25_gcq_driver); |
| |
| MODULE_DESCRIPTION("ADC driver for Freescale mx25"); |
| MODULE_AUTHOR("Markus Pargmann <mpa@pengutronix.de>"); |
| MODULE_LICENSE("GPL v2"); |