diff options
Diffstat (limited to 'drivers/iio/adc/rzg2l_adc.c')
| -rw-r--r-- | drivers/iio/adc/rzg2l_adc.c | 606 |
1 files changed, 606 insertions, 0 deletions
diff --git a/drivers/iio/adc/rzg2l_adc.c b/drivers/iio/adc/rzg2l_adc.c new file mode 100644 index 000000000000..1010e0511b3e --- /dev/null +++ b/drivers/iio/adc/rzg2l_adc.c @@ -0,0 +1,606 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * RZ/G2L A/D Converter driver + * + * Copyright (c) 2021 Renesas Electronics Europe GmbH + * + * Author: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> + */ + +#include <linux/bitfield.h> +#include <linux/cleanup.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/iio/adc-helpers.h> +#include <linux/iio/iio.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/property.h> +#include <linux/reset.h> + +#define DRIVER_NAME "rzg2l-adc" + +#define RZG2L_ADM(n) ((n) * 0x4) +#define RZG2L_ADM0_ADCE BIT(0) +#define RZG2L_ADM0_ADBSY BIT(1) +#define RZG2L_ADM0_PWDWNB BIT(2) +#define RZG2L_ADM0_SRESB BIT(15) +#define RZG2L_ADM1_TRG BIT(0) +#define RZG2L_ADM1_MS BIT(2) +#define RZG2L_ADM1_BS BIT(4) +#define RZG2L_ADM1_EGA_MASK GENMASK(13, 12) +#define RZG2L_ADM3_ADIL_MASK GENMASK(31, 24) +#define RZG2L_ADM3_ADCMP_MASK GENMASK(23, 16) + +#define RZG2L_ADINT 0x20 +#define RZG2L_ADINT_CSEEN BIT(16) +#define RZG2L_ADINT_INTS BIT(31) + +#define RZG2L_ADSTS 0x24 +#define RZG2L_ADSTS_CSEST BIT(16) + +#define RZG2L_ADIVC 0x28 +#define RZG2L_ADIVC_DIVADC_MASK GENMASK(8, 0) +#define RZG2L_ADIVC_DIVADC_4 FIELD_PREP(RZG2L_ADIVC_DIVADC_MASK, 0x4) + +#define RZG2L_ADFIL 0x2c + +#define RZG2L_ADCR(n) (0x30 + ((n) * 0x4)) +#define RZG2L_ADCR_AD_MASK GENMASK(11, 0) + +#define RZG2L_ADC_MAX_CHANNELS 9 +#define RZG2L_ADC_TIMEOUT usecs_to_jiffies(1 * 4) + +/** + * struct rzg2l_adc_hw_params - ADC hardware specific parameters + * @default_adsmp: default ADC sampling period (see ADM3 register); index 0 is + * used for voltage channels, index 1 is used for temperature channel + * @adsmp_mask: ADC sampling period mask (see ADM3 register) + * @adint_inten_mask: conversion end interrupt mask (see ADINT register) + * @default_adcmp: default ADC cmp (see ADM3 register) + * @num_channels: number of supported channels + * @adivc: specifies if ADVIC register is available + */ +struct rzg2l_adc_hw_params { + u16 default_adsmp[2]; + u16 adsmp_mask; + u16 adint_inten_mask; + u8 default_adcmp; + u8 num_channels; + bool adivc; +}; + +struct rzg2l_adc_data { + const struct iio_chan_spec *channels; + u8 num_channels; +}; + +struct rzg2l_adc { + void __iomem *base; + struct reset_control *presetn; + struct reset_control *adrstn; + const struct rzg2l_adc_data *data; + const struct rzg2l_adc_hw_params *hw_params; + struct completion completion; + struct mutex lock; + u16 last_val[RZG2L_ADC_MAX_CHANNELS]; +}; + +/** + * struct rzg2l_adc_channel - ADC channel descriptor + * @name: ADC channel name + * @type: ADC channel type + */ +struct rzg2l_adc_channel { + const char * const name; + enum iio_chan_type type; +}; + +static const struct rzg2l_adc_channel rzg2l_adc_channels[] = { + { "adc0", IIO_VOLTAGE }, + { "adc1", IIO_VOLTAGE }, + { "adc2", IIO_VOLTAGE }, + { "adc3", IIO_VOLTAGE }, + { "adc4", IIO_VOLTAGE }, + { "adc5", IIO_VOLTAGE }, + { "adc6", IIO_VOLTAGE }, + { "adc7", IIO_VOLTAGE }, + { "adc8", IIO_TEMP }, +}; + +static unsigned int rzg2l_adc_readl(struct rzg2l_adc *adc, u32 reg) +{ + return readl(adc->base + reg); +} + +static void rzg2l_adc_writel(struct rzg2l_adc *adc, unsigned int reg, u32 val) +{ + writel(val, adc->base + reg); +} + +static void rzg2l_adc_pwr(struct rzg2l_adc *adc, bool on) +{ + u32 reg; + + reg = rzg2l_adc_readl(adc, RZG2L_ADM(0)); + if (on) + reg |= RZG2L_ADM0_PWDWNB; + else + reg &= ~RZG2L_ADM0_PWDWNB; + rzg2l_adc_writel(adc, RZG2L_ADM(0), reg); + udelay(2); +} + +static void rzg2l_adc_start_stop(struct rzg2l_adc *adc, bool start) +{ + int ret; + u32 reg; + + reg = rzg2l_adc_readl(adc, RZG2L_ADM(0)); + if (start) + reg |= RZG2L_ADM0_ADCE; + else + reg &= ~RZG2L_ADM0_ADCE; + rzg2l_adc_writel(adc, RZG2L_ADM(0), reg); + + if (start) + return; + + ret = read_poll_timeout(rzg2l_adc_readl, reg, !(reg & (RZG2L_ADM0_ADBSY | RZG2L_ADM0_ADCE)), + 200, 1000, true, adc, RZG2L_ADM(0)); + if (ret) + pr_err("%s stopping ADC timed out\n", __func__); +} + +static void rzg2l_set_trigger(struct rzg2l_adc *adc) +{ + u32 reg; + + /* + * Setup ADM1 for SW trigger + * EGA[13:12] - Set 00 to indicate hardware trigger is invalid + * BS[4] - Enable 1-buffer mode + * MS[1] - Enable Select mode + * TRG[0] - Enable software trigger mode + */ + reg = rzg2l_adc_readl(adc, RZG2L_ADM(1)); + reg &= ~RZG2L_ADM1_EGA_MASK; + reg &= ~RZG2L_ADM1_BS; + reg &= ~RZG2L_ADM1_TRG; + reg |= RZG2L_ADM1_MS; + rzg2l_adc_writel(adc, RZG2L_ADM(1), reg); +} + +static u8 rzg2l_adc_ch_to_adsmp_index(u8 ch) +{ + if (rzg2l_adc_channels[ch].type == IIO_VOLTAGE) + return 0; + + return 1; +} + +static int rzg2l_adc_conversion_setup(struct rzg2l_adc *adc, u8 ch) +{ + const struct rzg2l_adc_hw_params *hw_params = adc->hw_params; + u8 index = rzg2l_adc_ch_to_adsmp_index(ch); + u32 reg; + + if (rzg2l_adc_readl(adc, RZG2L_ADM(0)) & RZG2L_ADM0_ADBSY) + return -EBUSY; + + rzg2l_set_trigger(adc); + + /* Select analog input channel subjected to conversion. */ + reg = rzg2l_adc_readl(adc, RZG2L_ADM(2)); + reg &= ~GENMASK(hw_params->num_channels - 1, 0); + reg |= BIT(ch); + rzg2l_adc_writel(adc, RZG2L_ADM(2), reg); + + reg = rzg2l_adc_readl(adc, RZG2L_ADM(3)); + reg &= ~hw_params->adsmp_mask; + reg |= hw_params->default_adsmp[index]; + rzg2l_adc_writel(adc, RZG2L_ADM(3), reg); + + /* + * Setup ADINT + * INTS[31] - Select pulse signal + * CSEEN[16] - Enable channel select error interrupt + * INTEN[7:0] - Select channel interrupt + */ + reg = rzg2l_adc_readl(adc, RZG2L_ADINT); + reg &= ~RZG2L_ADINT_INTS; + reg &= ~hw_params->adint_inten_mask; + reg |= (RZG2L_ADINT_CSEEN | BIT(ch)); + rzg2l_adc_writel(adc, RZG2L_ADINT, reg); + + return 0; +} + +static int rzg2l_adc_conversion(struct iio_dev *indio_dev, struct rzg2l_adc *adc, u8 ch) +{ + const struct rzg2l_adc_hw_params *hw_params = adc->hw_params; + struct device *dev = indio_dev->dev.parent; + int ret; + + ret = pm_runtime_resume_and_get(dev); + if (ret) + return ret; + + ret = rzg2l_adc_conversion_setup(adc, ch); + if (ret) + goto rpm_put; + + reinit_completion(&adc->completion); + + rzg2l_adc_start_stop(adc, true); + + if (!wait_for_completion_timeout(&adc->completion, RZG2L_ADC_TIMEOUT)) { + rzg2l_adc_writel(adc, RZG2L_ADINT, + rzg2l_adc_readl(adc, RZG2L_ADINT) & ~hw_params->adint_inten_mask); + ret = -ETIMEDOUT; + } + + rzg2l_adc_start_stop(adc, false); + +rpm_put: + pm_runtime_put_autosuspend(dev); + return ret; +} + +static int rzg2l_adc_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct rzg2l_adc *adc = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: { + if (chan->type != IIO_VOLTAGE && chan->type != IIO_TEMP) + return -EINVAL; + + guard(mutex)(&adc->lock); + + ret = rzg2l_adc_conversion(indio_dev, adc, chan->channel); + if (ret) + return ret; + + *val = adc->last_val[chan->channel]; + + return IIO_VAL_INT; + } + + default: + return -EINVAL; + } +} + +static int rzg2l_adc_read_label(struct iio_dev *iio_dev, + const struct iio_chan_spec *chan, + char *label) +{ + return sysfs_emit(label, "%s\n", rzg2l_adc_channels[chan->channel].name); +} + +static const struct iio_info rzg2l_adc_iio_info = { + .read_raw = rzg2l_adc_read_raw, + .read_label = rzg2l_adc_read_label, +}; + +static irqreturn_t rzg2l_adc_isr(int irq, void *dev_id) +{ + struct rzg2l_adc *adc = dev_id; + const struct rzg2l_adc_hw_params *hw_params = adc->hw_params; + unsigned long intst; + u32 reg; + int ch; + + reg = rzg2l_adc_readl(adc, RZG2L_ADSTS); + + /* A/D conversion channel select error interrupt */ + if (reg & RZG2L_ADSTS_CSEST) { + rzg2l_adc_writel(adc, RZG2L_ADSTS, reg); + return IRQ_HANDLED; + } + + intst = reg & GENMASK(hw_params->num_channels - 1, 0); + if (!intst) + return IRQ_NONE; + + for_each_set_bit(ch, &intst, hw_params->num_channels) + adc->last_val[ch] = rzg2l_adc_readl(adc, RZG2L_ADCR(ch)) & RZG2L_ADCR_AD_MASK; + + /* clear the channel interrupt */ + rzg2l_adc_writel(adc, RZG2L_ADSTS, reg); + + complete(&adc->completion); + + return IRQ_HANDLED; +} + +static const struct iio_chan_spec rzg2l_adc_chan_template = { + .indexed = 1, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), +}; + +static int rzg2l_adc_parse_properties(struct platform_device *pdev, struct rzg2l_adc *adc) +{ + const struct rzg2l_adc_hw_params *hw_params = adc->hw_params; + struct iio_chan_spec *chan_array; + struct rzg2l_adc_data *data; + int num_channels; + u8 i; + + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + num_channels = devm_iio_adc_device_alloc_chaninfo_se(&pdev->dev, + &rzg2l_adc_chan_template, + hw_params->num_channels - 1, + &chan_array); + if (num_channels < 0) + return num_channels; + + if (num_channels > hw_params->num_channels) + return dev_err_probe(&pdev->dev, -EINVAL, + "num of channel children out of range\n"); + + for (i = 0; i < num_channels; i++) { + int channel = chan_array[i].channel; + + chan_array[i].datasheet_name = rzg2l_adc_channels[channel].name; + chan_array[i].type = rzg2l_adc_channels[channel].type; + } + + data->num_channels = num_channels; + data->channels = chan_array; + adc->data = data; + + return 0; +} + +static int rzg2l_adc_hw_init(struct device *dev, struct rzg2l_adc *adc) +{ + const struct rzg2l_adc_hw_params *hw_params = adc->hw_params; + u32 reg; + int ret; + + ret = pm_runtime_resume_and_get(dev); + if (ret) + return ret; + + /* SW reset */ + reg = rzg2l_adc_readl(adc, RZG2L_ADM(0)); + reg |= RZG2L_ADM0_SRESB; + rzg2l_adc_writel(adc, RZG2L_ADM(0), reg); + + ret = read_poll_timeout(rzg2l_adc_readl, reg, reg & RZG2L_ADM0_SRESB, + 200, 1000, false, adc, RZG2L_ADM(0)); + if (ret) + goto exit_hw_init; + + if (hw_params->adivc) { + /* Only division by 4 can be set */ + reg = rzg2l_adc_readl(adc, RZG2L_ADIVC); + reg &= ~RZG2L_ADIVC_DIVADC_MASK; + reg |= RZG2L_ADIVC_DIVADC_4; + rzg2l_adc_writel(adc, RZG2L_ADIVC, reg); + } + + /* + * Setup AMD3 + * ADIL[31:24] - Should be always set to 0 + * ADCMP[23:16] - Should be always set to 0xe + * ADSMP[15:0] - Set default (0x578) sampling period + */ + reg = rzg2l_adc_readl(adc, RZG2L_ADM(3)); + reg &= ~RZG2L_ADM3_ADIL_MASK; + reg &= ~RZG2L_ADM3_ADCMP_MASK; + reg &= ~hw_params->adsmp_mask; + reg |= FIELD_PREP(RZG2L_ADM3_ADCMP_MASK, hw_params->default_adcmp) | + hw_params->default_adsmp[0]; + + rzg2l_adc_writel(adc, RZG2L_ADM(3), reg); + +exit_hw_init: + pm_runtime_put_autosuspend(dev); + return ret; +} + +static int rzg2l_adc_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct iio_dev *indio_dev; + struct rzg2l_adc *adc; + int ret; + int irq; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*adc)); + if (!indio_dev) + return -ENOMEM; + + platform_set_drvdata(pdev, indio_dev); + + adc = iio_priv(indio_dev); + + adc->hw_params = device_get_match_data(dev); + if (!adc->hw_params || adc->hw_params->num_channels > RZG2L_ADC_MAX_CHANNELS) + return -EINVAL; + + ret = rzg2l_adc_parse_properties(pdev, adc); + if (ret) + return ret; + + mutex_init(&adc->lock); + + adc->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(adc->base)) + return PTR_ERR(adc->base); + + adc->adrstn = devm_reset_control_get_exclusive_deasserted(dev, "adrst-n"); + if (IS_ERR(adc->adrstn)) + return dev_err_probe(dev, PTR_ERR(adc->adrstn), + "failed to get/deassert adrst-n\n"); + + adc->presetn = devm_reset_control_get_exclusive_deasserted(dev, "presetn"); + if (IS_ERR(adc->presetn)) + return dev_err_probe(dev, PTR_ERR(adc->presetn), + "failed to get/deassert presetn\n"); + + pm_runtime_set_autosuspend_delay(dev, 300); + pm_runtime_use_autosuspend(dev); + ret = devm_pm_runtime_enable(dev); + if (ret) + return ret; + + ret = rzg2l_adc_hw_init(dev, adc); + if (ret) + return dev_err_probe(&pdev->dev, ret, + "failed to initialize ADC HW\n"); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + ret = devm_request_irq(dev, irq, rzg2l_adc_isr, + 0, dev_name(dev), adc); + if (ret < 0) + return ret; + + init_completion(&adc->completion); + + indio_dev->name = DRIVER_NAME; + indio_dev->info = &rzg2l_adc_iio_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = adc->data->channels; + indio_dev->num_channels = adc->data->num_channels; + + return devm_iio_device_register(dev, indio_dev); +} + +static const struct rzg2l_adc_hw_params rzg2l_hw_params = { + .num_channels = 8, + .default_adcmp = 0xe, + .default_adsmp = { 0x578 }, + .adsmp_mask = GENMASK(15, 0), + .adint_inten_mask = GENMASK(7, 0), + .adivc = true +}; + +static const struct rzg2l_adc_hw_params rzg3s_hw_params = { + .num_channels = 9, + .default_adcmp = 0x1d, + .default_adsmp = { 0x7f, 0xff }, + .adsmp_mask = GENMASK(7, 0), + .adint_inten_mask = GENMASK(11, 0), +}; + +static const struct of_device_id rzg2l_adc_match[] = { + { .compatible = "renesas,r9a08g045-adc", .data = &rzg3s_hw_params }, + { .compatible = "renesas,rzg2l-adc", .data = &rzg2l_hw_params }, + { } +}; +MODULE_DEVICE_TABLE(of, rzg2l_adc_match); + +static int rzg2l_adc_pm_runtime_suspend(struct device *dev) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct rzg2l_adc *adc = iio_priv(indio_dev); + + rzg2l_adc_pwr(adc, false); + + return 0; +} + +static int rzg2l_adc_pm_runtime_resume(struct device *dev) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct rzg2l_adc *adc = iio_priv(indio_dev); + + rzg2l_adc_pwr(adc, true); + + return 0; +} + +static int rzg2l_adc_suspend(struct device *dev) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct rzg2l_adc *adc = iio_priv(indio_dev); + struct reset_control_bulk_data resets[] = { + { .rstc = adc->presetn }, + { .rstc = adc->adrstn }, + }; + int ret; + + ret = pm_runtime_force_suspend(dev); + if (ret) + return ret; + + ret = reset_control_bulk_assert(ARRAY_SIZE(resets), resets); + if (ret) + goto rpm_restore; + + return 0; + +rpm_restore: + pm_runtime_force_resume(dev); + return ret; +} + +static int rzg2l_adc_resume(struct device *dev) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct rzg2l_adc *adc = iio_priv(indio_dev); + struct reset_control_bulk_data resets[] = { + { .rstc = adc->adrstn }, + { .rstc = adc->presetn }, + }; + int ret; + + ret = reset_control_bulk_deassert(ARRAY_SIZE(resets), resets); + if (ret) + return ret; + + ret = pm_runtime_force_resume(dev); + if (ret) + goto resets_restore; + + ret = rzg2l_adc_hw_init(dev, adc); + if (ret) + goto rpm_restore; + + return 0; + +rpm_restore: + pm_runtime_force_suspend(dev); +resets_restore: + reset_control_bulk_assert(ARRAY_SIZE(resets), resets); + return ret; +} + +static const struct dev_pm_ops rzg2l_adc_pm_ops = { + RUNTIME_PM_OPS(rzg2l_adc_pm_runtime_suspend, rzg2l_adc_pm_runtime_resume, NULL) + SYSTEM_SLEEP_PM_OPS(rzg2l_adc_suspend, rzg2l_adc_resume) +}; + +static struct platform_driver rzg2l_adc_driver = { + .probe = rzg2l_adc_probe, + .driver = { + .name = DRIVER_NAME, + .of_match_table = rzg2l_adc_match, + .pm = pm_ptr(&rzg2l_adc_pm_ops), + }, +}; + +module_platform_driver(rzg2l_adc_driver); + +MODULE_AUTHOR("Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>"); +MODULE_DESCRIPTION("Renesas RZ/G2L ADC driver"); +MODULE_LICENSE("GPL v2"); +MODULE_IMPORT_NS("IIO_DRIVER"); |