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path: root/drivers/iio/adc/aspeed_adc.c
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-rw-r--r--drivers/iio/adc/aspeed_adc.c728
1 files changed, 728 insertions, 0 deletions
diff --git a/drivers/iio/adc/aspeed_adc.c b/drivers/iio/adc/aspeed_adc.c
new file mode 100644
index 000000000..998e8bcc0
--- /dev/null
+++ b/drivers/iio/adc/aspeed_adc.c
@@ -0,0 +1,728 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Aspeed AST2400/2500/2600 ADC
+ *
+ * Copyright (C) 2017 Google, Inc.
+ * Copyright (C) 2021 Aspeed Technology Inc.
+ *
+ * ADC clock formula:
+ * Ast2400/Ast2500:
+ * clock period = period of PCLK * 2 * (ADC0C[31:17] + 1) * (ADC0C[9:0] + 1)
+ * Ast2600:
+ * clock period = period of PCLK * 2 * (ADC0C[15:0] + 1)
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/reset.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+#include <linux/bitfield.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/driver.h>
+#include <linux/iopoll.h>
+
+#define ASPEED_RESOLUTION_BITS 10
+#define ASPEED_CLOCKS_PER_SAMPLE 12
+
+#define ASPEED_REG_ENGINE_CONTROL 0x00
+#define ASPEED_REG_INTERRUPT_CONTROL 0x04
+#define ASPEED_REG_VGA_DETECT_CONTROL 0x08
+#define ASPEED_REG_CLOCK_CONTROL 0x0C
+#define ASPEED_REG_COMPENSATION_TRIM 0xC4
+/*
+ * The register offset between 0xC8~0xCC can be read and won't affect the
+ * hardware logic in each version of ADC.
+ */
+#define ASPEED_REG_MAX 0xD0
+
+#define ASPEED_ADC_ENGINE_ENABLE BIT(0)
+#define ASPEED_ADC_OP_MODE GENMASK(3, 1)
+#define ASPEED_ADC_OP_MODE_PWR_DOWN 0
+#define ASPEED_ADC_OP_MODE_STANDBY 1
+#define ASPEED_ADC_OP_MODE_NORMAL 7
+#define ASPEED_ADC_CTRL_COMPENSATION BIT(4)
+#define ASPEED_ADC_AUTO_COMPENSATION BIT(5)
+/*
+ * Bit 6 determines not only the reference voltage range but also the dividing
+ * circuit for battery sensing.
+ */
+#define ASPEED_ADC_REF_VOLTAGE GENMASK(7, 6)
+#define ASPEED_ADC_REF_VOLTAGE_2500mV 0
+#define ASPEED_ADC_REF_VOLTAGE_1200mV 1
+#define ASPEED_ADC_REF_VOLTAGE_EXT_HIGH 2
+#define ASPEED_ADC_REF_VOLTAGE_EXT_LOW 3
+#define ASPEED_ADC_BAT_SENSING_DIV BIT(6)
+#define ASPEED_ADC_BAT_SENSING_DIV_2_3 0
+#define ASPEED_ADC_BAT_SENSING_DIV_1_3 1
+#define ASPEED_ADC_CTRL_INIT_RDY BIT(8)
+#define ASPEED_ADC_CH7_MODE BIT(12)
+#define ASPEED_ADC_CH7_NORMAL 0
+#define ASPEED_ADC_CH7_BAT 1
+#define ASPEED_ADC_BAT_SENSING_ENABLE BIT(13)
+#define ASPEED_ADC_CTRL_CHANNEL GENMASK(31, 16)
+#define ASPEED_ADC_CTRL_CHANNEL_ENABLE(ch) FIELD_PREP(ASPEED_ADC_CTRL_CHANNEL, BIT(ch))
+
+#define ASPEED_ADC_INIT_POLLING_TIME 500
+#define ASPEED_ADC_INIT_TIMEOUT 500000
+/*
+ * When the sampling rate is too high, the ADC may not have enough charging
+ * time, resulting in a low voltage value. Thus, the default uses a slow
+ * sampling rate for most use cases.
+ */
+#define ASPEED_ADC_DEF_SAMPLING_RATE 65000
+
+struct aspeed_adc_trim_locate {
+ const unsigned int offset;
+ const unsigned int field;
+};
+
+struct aspeed_adc_model_data {
+ const char *model_name;
+ unsigned int min_sampling_rate; // Hz
+ unsigned int max_sampling_rate; // Hz
+ unsigned int vref_fixed_mv;
+ bool wait_init_sequence;
+ bool need_prescaler;
+ bool bat_sense_sup;
+ u8 scaler_bit_width;
+ unsigned int num_channels;
+ const struct aspeed_adc_trim_locate *trim_locate;
+};
+
+struct adc_gain {
+ u8 mult;
+ u8 div;
+};
+
+struct aspeed_adc_data {
+ struct device *dev;
+ const struct aspeed_adc_model_data *model_data;
+ struct regulator *regulator;
+ void __iomem *base;
+ spinlock_t clk_lock;
+ struct clk_hw *fixed_div_clk;
+ struct clk_hw *clk_prescaler;
+ struct clk_hw *clk_scaler;
+ struct reset_control *rst;
+ int vref_mv;
+ u32 sample_period_ns;
+ int cv;
+ bool battery_sensing;
+ struct adc_gain battery_mode_gain;
+};
+
+#define ASPEED_CHAN(_idx, _data_reg_addr) { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .channel = (_idx), \
+ .address = (_data_reg_addr), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
+ BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
+ BIT(IIO_CHAN_INFO_OFFSET), \
+}
+
+static const struct iio_chan_spec aspeed_adc_iio_channels[] = {
+ ASPEED_CHAN(0, 0x10),
+ ASPEED_CHAN(1, 0x12),
+ ASPEED_CHAN(2, 0x14),
+ ASPEED_CHAN(3, 0x16),
+ ASPEED_CHAN(4, 0x18),
+ ASPEED_CHAN(5, 0x1A),
+ ASPEED_CHAN(6, 0x1C),
+ ASPEED_CHAN(7, 0x1E),
+ ASPEED_CHAN(8, 0x20),
+ ASPEED_CHAN(9, 0x22),
+ ASPEED_CHAN(10, 0x24),
+ ASPEED_CHAN(11, 0x26),
+ ASPEED_CHAN(12, 0x28),
+ ASPEED_CHAN(13, 0x2A),
+ ASPEED_CHAN(14, 0x2C),
+ ASPEED_CHAN(15, 0x2E),
+};
+
+#define ASPEED_BAT_CHAN(_idx, _data_reg_addr) { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .channel = (_idx), \
+ .address = (_data_reg_addr), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_OFFSET), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
+ BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+}
+static const struct iio_chan_spec aspeed_adc_iio_bat_channels[] = {
+ ASPEED_CHAN(0, 0x10),
+ ASPEED_CHAN(1, 0x12),
+ ASPEED_CHAN(2, 0x14),
+ ASPEED_CHAN(3, 0x16),
+ ASPEED_CHAN(4, 0x18),
+ ASPEED_CHAN(5, 0x1A),
+ ASPEED_CHAN(6, 0x1C),
+ ASPEED_BAT_CHAN(7, 0x1E),
+};
+
+static int aspeed_adc_set_trim_data(struct iio_dev *indio_dev)
+{
+ struct device_node *syscon;
+ struct regmap *scu;
+ u32 scu_otp, trimming_val;
+ struct aspeed_adc_data *data = iio_priv(indio_dev);
+
+ syscon = of_find_node_by_name(NULL, "syscon");
+ if (syscon == NULL) {
+ dev_warn(data->dev, "Couldn't find syscon node\n");
+ return -EOPNOTSUPP;
+ }
+ scu = syscon_node_to_regmap(syscon);
+ of_node_put(syscon);
+ if (IS_ERR(scu)) {
+ dev_warn(data->dev, "Failed to get syscon regmap\n");
+ return -EOPNOTSUPP;
+ }
+ if (data->model_data->trim_locate) {
+ if (regmap_read(scu, data->model_data->trim_locate->offset,
+ &scu_otp)) {
+ dev_warn(data->dev,
+ "Failed to get adc trimming data\n");
+ trimming_val = 0x8;
+ } else {
+ trimming_val =
+ ((scu_otp) &
+ (data->model_data->trim_locate->field)) >>
+ __ffs(data->model_data->trim_locate->field);
+ if (!trimming_val)
+ trimming_val = 0x8;
+ }
+ dev_dbg(data->dev,
+ "trimming val = %d, offset = %08x, fields = %08x\n",
+ trimming_val, data->model_data->trim_locate->offset,
+ data->model_data->trim_locate->field);
+ writel(trimming_val, data->base + ASPEED_REG_COMPENSATION_TRIM);
+ }
+ return 0;
+}
+
+static int aspeed_adc_compensation(struct iio_dev *indio_dev)
+{
+ struct aspeed_adc_data *data = iio_priv(indio_dev);
+ u32 index, adc_raw = 0;
+ u32 adc_engine_control_reg_val;
+
+ adc_engine_control_reg_val =
+ readl(data->base + ASPEED_REG_ENGINE_CONTROL);
+ adc_engine_control_reg_val &= ~ASPEED_ADC_OP_MODE;
+ adc_engine_control_reg_val |=
+ (FIELD_PREP(ASPEED_ADC_OP_MODE, ASPEED_ADC_OP_MODE_NORMAL) |
+ ASPEED_ADC_ENGINE_ENABLE);
+ /*
+ * Enable compensating sensing:
+ * After that, the input voltage of ADC will force to half of the reference
+ * voltage. So the expected reading raw data will become half of the max
+ * value. We can get compensating value = 0x200 - ADC read raw value.
+ * It is recommended to average at least 10 samples to get a final CV.
+ */
+ writel(adc_engine_control_reg_val | ASPEED_ADC_CTRL_COMPENSATION |
+ ASPEED_ADC_CTRL_CHANNEL_ENABLE(0),
+ data->base + ASPEED_REG_ENGINE_CONTROL);
+ /*
+ * After enable compensating sensing mode need to wait some time for ADC stable
+ * Experiment result is 1ms.
+ */
+ mdelay(1);
+
+ for (index = 0; index < 16; index++) {
+ /*
+ * Waiting for the sampling period ensures that the value acquired
+ * is fresh each time.
+ */
+ ndelay(data->sample_period_ns);
+ adc_raw += readw(data->base + aspeed_adc_iio_channels[0].address);
+ }
+ adc_raw >>= 4;
+ data->cv = BIT(ASPEED_RESOLUTION_BITS - 1) - adc_raw;
+ writel(adc_engine_control_reg_val,
+ data->base + ASPEED_REG_ENGINE_CONTROL);
+ dev_dbg(data->dev, "Compensating value = %d\n", data->cv);
+
+ return 0;
+}
+
+static int aspeed_adc_set_sampling_rate(struct iio_dev *indio_dev, u32 rate)
+{
+ struct aspeed_adc_data *data = iio_priv(indio_dev);
+
+ if (rate < data->model_data->min_sampling_rate ||
+ rate > data->model_data->max_sampling_rate)
+ return -EINVAL;
+ /* Each sampling needs 12 clocks to convert.*/
+ clk_set_rate(data->clk_scaler->clk, rate * ASPEED_CLOCKS_PER_SAMPLE);
+ rate = clk_get_rate(data->clk_scaler->clk);
+ data->sample_period_ns = DIV_ROUND_UP_ULL(
+ (u64)NSEC_PER_SEC * ASPEED_CLOCKS_PER_SAMPLE, rate);
+ dev_dbg(data->dev, "Adc clock = %d sample period = %d ns", rate,
+ data->sample_period_ns);
+
+ return 0;
+}
+
+static int aspeed_adc_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct aspeed_adc_data *data = iio_priv(indio_dev);
+ u32 adc_engine_control_reg_val;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ if (data->battery_sensing && chan->channel == 7) {
+ adc_engine_control_reg_val =
+ readl(data->base + ASPEED_REG_ENGINE_CONTROL);
+ writel(adc_engine_control_reg_val |
+ FIELD_PREP(ASPEED_ADC_CH7_MODE,
+ ASPEED_ADC_CH7_BAT) |
+ ASPEED_ADC_BAT_SENSING_ENABLE,
+ data->base + ASPEED_REG_ENGINE_CONTROL);
+ /*
+ * After enable battery sensing mode need to wait some time for adc stable
+ * Experiment result is 1ms.
+ */
+ mdelay(1);
+ *val = readw(data->base + chan->address);
+ *val = (*val * data->battery_mode_gain.mult) /
+ data->battery_mode_gain.div;
+ /* Restore control register value */
+ writel(adc_engine_control_reg_val,
+ data->base + ASPEED_REG_ENGINE_CONTROL);
+ } else
+ *val = readw(data->base + chan->address);
+ return IIO_VAL_INT;
+
+ case IIO_CHAN_INFO_OFFSET:
+ if (data->battery_sensing && chan->channel == 7)
+ *val = (data->cv * data->battery_mode_gain.mult) /
+ data->battery_mode_gain.div;
+ else
+ *val = data->cv;
+ return IIO_VAL_INT;
+
+ case IIO_CHAN_INFO_SCALE:
+ *val = data->vref_mv;
+ *val2 = ASPEED_RESOLUTION_BITS;
+ return IIO_VAL_FRACTIONAL_LOG2;
+
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ *val = clk_get_rate(data->clk_scaler->clk) /
+ ASPEED_CLOCKS_PER_SAMPLE;
+ return IIO_VAL_INT;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static int aspeed_adc_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ switch (mask) {
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ return aspeed_adc_set_sampling_rate(indio_dev, val);
+
+ case IIO_CHAN_INFO_SCALE:
+ case IIO_CHAN_INFO_RAW:
+ /*
+ * Technically, these could be written but the only reasons
+ * for doing so seem better handled in userspace. EPERM is
+ * returned to signal this is a policy choice rather than a
+ * hardware limitation.
+ */
+ return -EPERM;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static int aspeed_adc_reg_access(struct iio_dev *indio_dev,
+ unsigned int reg, unsigned int writeval,
+ unsigned int *readval)
+{
+ struct aspeed_adc_data *data = iio_priv(indio_dev);
+
+ if (!readval || reg % 4 || reg > ASPEED_REG_MAX)
+ return -EINVAL;
+
+ *readval = readl(data->base + reg);
+
+ return 0;
+}
+
+static const struct iio_info aspeed_adc_iio_info = {
+ .read_raw = aspeed_adc_read_raw,
+ .write_raw = aspeed_adc_write_raw,
+ .debugfs_reg_access = aspeed_adc_reg_access,
+};
+
+static void aspeed_adc_unregister_fixed_divider(void *data)
+{
+ struct clk_hw *clk = data;
+
+ clk_hw_unregister_fixed_factor(clk);
+}
+
+static void aspeed_adc_reset_assert(void *data)
+{
+ struct reset_control *rst = data;
+
+ reset_control_assert(rst);
+}
+
+static void aspeed_adc_clk_disable_unprepare(void *data)
+{
+ struct clk *clk = data;
+
+ clk_disable_unprepare(clk);
+}
+
+static void aspeed_adc_power_down(void *data)
+{
+ struct aspeed_adc_data *priv_data = data;
+
+ writel(FIELD_PREP(ASPEED_ADC_OP_MODE, ASPEED_ADC_OP_MODE_PWR_DOWN),
+ priv_data->base + ASPEED_REG_ENGINE_CONTROL);
+}
+
+static void aspeed_adc_reg_disable(void *data)
+{
+ struct regulator *reg = data;
+
+ regulator_disable(reg);
+}
+
+static int aspeed_adc_vref_config(struct iio_dev *indio_dev)
+{
+ struct aspeed_adc_data *data = iio_priv(indio_dev);
+ int ret;
+ u32 adc_engine_control_reg_val;
+
+ if (data->model_data->vref_fixed_mv) {
+ data->vref_mv = data->model_data->vref_fixed_mv;
+ return 0;
+ }
+ adc_engine_control_reg_val =
+ readl(data->base + ASPEED_REG_ENGINE_CONTROL);
+ data->regulator = devm_regulator_get_optional(data->dev, "vref");
+ if (!IS_ERR(data->regulator)) {
+ ret = regulator_enable(data->regulator);
+ if (ret)
+ return ret;
+ ret = devm_add_action_or_reset(
+ data->dev, aspeed_adc_reg_disable, data->regulator);
+ if (ret)
+ return ret;
+ data->vref_mv = regulator_get_voltage(data->regulator);
+ /* Conversion from uV to mV */
+ data->vref_mv /= 1000;
+ if ((data->vref_mv >= 1550) && (data->vref_mv <= 2700))
+ writel(adc_engine_control_reg_val |
+ FIELD_PREP(
+ ASPEED_ADC_REF_VOLTAGE,
+ ASPEED_ADC_REF_VOLTAGE_EXT_HIGH),
+ data->base + ASPEED_REG_ENGINE_CONTROL);
+ else if ((data->vref_mv >= 900) && (data->vref_mv <= 1650))
+ writel(adc_engine_control_reg_val |
+ FIELD_PREP(
+ ASPEED_ADC_REF_VOLTAGE,
+ ASPEED_ADC_REF_VOLTAGE_EXT_LOW),
+ data->base + ASPEED_REG_ENGINE_CONTROL);
+ else {
+ dev_err(data->dev, "Regulator voltage %d not support",
+ data->vref_mv);
+ return -EOPNOTSUPP;
+ }
+ } else {
+ if (PTR_ERR(data->regulator) != -ENODEV)
+ return PTR_ERR(data->regulator);
+ data->vref_mv = 2500000;
+ of_property_read_u32(data->dev->of_node,
+ "aspeed,int-vref-microvolt",
+ &data->vref_mv);
+ /* Conversion from uV to mV */
+ data->vref_mv /= 1000;
+ if (data->vref_mv == 2500)
+ writel(adc_engine_control_reg_val |
+ FIELD_PREP(ASPEED_ADC_REF_VOLTAGE,
+ ASPEED_ADC_REF_VOLTAGE_2500mV),
+ data->base + ASPEED_REG_ENGINE_CONTROL);
+ else if (data->vref_mv == 1200)
+ writel(adc_engine_control_reg_val |
+ FIELD_PREP(ASPEED_ADC_REF_VOLTAGE,
+ ASPEED_ADC_REF_VOLTAGE_1200mV),
+ data->base + ASPEED_REG_ENGINE_CONTROL);
+ else {
+ dev_err(data->dev, "Voltage %d not support", data->vref_mv);
+ return -EOPNOTSUPP;
+ }
+ }
+
+ return 0;
+}
+
+static int aspeed_adc_probe(struct platform_device *pdev)
+{
+ struct iio_dev *indio_dev;
+ struct aspeed_adc_data *data;
+ int ret;
+ u32 adc_engine_control_reg_val;
+ unsigned long scaler_flags = 0;
+ char clk_name[32], clk_parent_name[32];
+
+ indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*data));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ data = iio_priv(indio_dev);
+ data->dev = &pdev->dev;
+ data->model_data = of_device_get_match_data(&pdev->dev);
+ platform_set_drvdata(pdev, indio_dev);
+
+ data->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(data->base))
+ return PTR_ERR(data->base);
+
+ /* Register ADC clock prescaler with source specified by device tree. */
+ spin_lock_init(&data->clk_lock);
+ snprintf(clk_parent_name, ARRAY_SIZE(clk_parent_name), "%s",
+ of_clk_get_parent_name(pdev->dev.of_node, 0));
+ snprintf(clk_name, ARRAY_SIZE(clk_name), "%s-fixed-div",
+ data->model_data->model_name);
+ data->fixed_div_clk = clk_hw_register_fixed_factor(
+ &pdev->dev, clk_name, clk_parent_name, 0, 1, 2);
+ if (IS_ERR(data->fixed_div_clk))
+ return PTR_ERR(data->fixed_div_clk);
+
+ ret = devm_add_action_or_reset(data->dev,
+ aspeed_adc_unregister_fixed_divider,
+ data->fixed_div_clk);
+ if (ret)
+ return ret;
+ snprintf(clk_parent_name, ARRAY_SIZE(clk_parent_name), clk_name);
+
+ if (data->model_data->need_prescaler) {
+ snprintf(clk_name, ARRAY_SIZE(clk_name), "%s-prescaler",
+ data->model_data->model_name);
+ data->clk_prescaler = devm_clk_hw_register_divider(
+ &pdev->dev, clk_name, clk_parent_name, 0,
+ data->base + ASPEED_REG_CLOCK_CONTROL, 17, 15, 0,
+ &data->clk_lock);
+ if (IS_ERR(data->clk_prescaler))
+ return PTR_ERR(data->clk_prescaler);
+ snprintf(clk_parent_name, ARRAY_SIZE(clk_parent_name),
+ clk_name);
+ scaler_flags = CLK_SET_RATE_PARENT;
+ }
+ /*
+ * Register ADC clock scaler downstream from the prescaler. Allow rate
+ * setting to adjust the prescaler as well.
+ */
+ snprintf(clk_name, ARRAY_SIZE(clk_name), "%s-scaler",
+ data->model_data->model_name);
+ data->clk_scaler = devm_clk_hw_register_divider(
+ &pdev->dev, clk_name, clk_parent_name, scaler_flags,
+ data->base + ASPEED_REG_CLOCK_CONTROL, 0,
+ data->model_data->scaler_bit_width,
+ data->model_data->need_prescaler ? CLK_DIVIDER_ONE_BASED : 0,
+ &data->clk_lock);
+ if (IS_ERR(data->clk_scaler))
+ return PTR_ERR(data->clk_scaler);
+
+ data->rst = devm_reset_control_get_shared(&pdev->dev, NULL);
+ if (IS_ERR(data->rst)) {
+ dev_err(&pdev->dev,
+ "invalid or missing reset controller device tree entry");
+ return PTR_ERR(data->rst);
+ }
+ reset_control_deassert(data->rst);
+
+ ret = devm_add_action_or_reset(data->dev, aspeed_adc_reset_assert,
+ data->rst);
+ if (ret)
+ return ret;
+
+ ret = aspeed_adc_vref_config(indio_dev);
+ if (ret)
+ return ret;
+
+ ret = aspeed_adc_set_trim_data(indio_dev);
+ if (ret)
+ return ret;
+
+ if (of_find_property(data->dev->of_node, "aspeed,battery-sensing",
+ NULL)) {
+ if (data->model_data->bat_sense_sup) {
+ data->battery_sensing = 1;
+ if (readl(data->base + ASPEED_REG_ENGINE_CONTROL) &
+ ASPEED_ADC_BAT_SENSING_DIV) {
+ data->battery_mode_gain.mult = 3;
+ data->battery_mode_gain.div = 1;
+ } else {
+ data->battery_mode_gain.mult = 3;
+ data->battery_mode_gain.div = 2;
+ }
+ } else
+ dev_warn(&pdev->dev,
+ "Failed to enable battery-sensing mode\n");
+ }
+
+ ret = clk_prepare_enable(data->clk_scaler->clk);
+ if (ret)
+ return ret;
+ ret = devm_add_action_or_reset(data->dev,
+ aspeed_adc_clk_disable_unprepare,
+ data->clk_scaler->clk);
+ if (ret)
+ return ret;
+ ret = aspeed_adc_set_sampling_rate(indio_dev,
+ ASPEED_ADC_DEF_SAMPLING_RATE);
+ if (ret)
+ return ret;
+
+ adc_engine_control_reg_val =
+ readl(data->base + ASPEED_REG_ENGINE_CONTROL);
+ adc_engine_control_reg_val |=
+ FIELD_PREP(ASPEED_ADC_OP_MODE, ASPEED_ADC_OP_MODE_NORMAL) |
+ ASPEED_ADC_ENGINE_ENABLE;
+ /* Enable engine in normal mode. */
+ writel(adc_engine_control_reg_val,
+ data->base + ASPEED_REG_ENGINE_CONTROL);
+
+ ret = devm_add_action_or_reset(data->dev, aspeed_adc_power_down,
+ data);
+ if (ret)
+ return ret;
+
+ if (data->model_data->wait_init_sequence) {
+ /* Wait for initial sequence complete. */
+ ret = readl_poll_timeout(data->base + ASPEED_REG_ENGINE_CONTROL,
+ adc_engine_control_reg_val,
+ adc_engine_control_reg_val &
+ ASPEED_ADC_CTRL_INIT_RDY,
+ ASPEED_ADC_INIT_POLLING_TIME,
+ ASPEED_ADC_INIT_TIMEOUT);
+ if (ret)
+ return ret;
+ }
+
+ aspeed_adc_compensation(indio_dev);
+ /* Start all channels in normal mode. */
+ adc_engine_control_reg_val =
+ readl(data->base + ASPEED_REG_ENGINE_CONTROL);
+ adc_engine_control_reg_val |= ASPEED_ADC_CTRL_CHANNEL;
+ writel(adc_engine_control_reg_val,
+ data->base + ASPEED_REG_ENGINE_CONTROL);
+
+ indio_dev->name = data->model_data->model_name;
+ indio_dev->info = &aspeed_adc_iio_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = data->battery_sensing ?
+ aspeed_adc_iio_bat_channels :
+ aspeed_adc_iio_channels;
+ indio_dev->num_channels = data->model_data->num_channels;
+
+ ret = devm_iio_device_register(data->dev, indio_dev);
+ return ret;
+}
+
+static const struct aspeed_adc_trim_locate ast2500_adc_trim = {
+ .offset = 0x154,
+ .field = GENMASK(31, 28),
+};
+
+static const struct aspeed_adc_trim_locate ast2600_adc0_trim = {
+ .offset = 0x5d0,
+ .field = GENMASK(3, 0),
+};
+
+static const struct aspeed_adc_trim_locate ast2600_adc1_trim = {
+ .offset = 0x5d0,
+ .field = GENMASK(7, 4),
+};
+
+static const struct aspeed_adc_model_data ast2400_model_data = {
+ .model_name = "ast2400-adc",
+ .vref_fixed_mv = 2500,
+ .min_sampling_rate = 10000,
+ .max_sampling_rate = 500000,
+ .need_prescaler = true,
+ .scaler_bit_width = 10,
+ .num_channels = 16,
+};
+
+static const struct aspeed_adc_model_data ast2500_model_data = {
+ .model_name = "ast2500-adc",
+ .vref_fixed_mv = 1800,
+ .min_sampling_rate = 1,
+ .max_sampling_rate = 1000000,
+ .wait_init_sequence = true,
+ .need_prescaler = true,
+ .scaler_bit_width = 10,
+ .num_channels = 16,
+ .trim_locate = &ast2500_adc_trim,
+};
+
+static const struct aspeed_adc_model_data ast2600_adc0_model_data = {
+ .model_name = "ast2600-adc0",
+ .min_sampling_rate = 10000,
+ .max_sampling_rate = 500000,
+ .wait_init_sequence = true,
+ .bat_sense_sup = true,
+ .scaler_bit_width = 16,
+ .num_channels = 8,
+ .trim_locate = &ast2600_adc0_trim,
+};
+
+static const struct aspeed_adc_model_data ast2600_adc1_model_data = {
+ .model_name = "ast2600-adc1",
+ .min_sampling_rate = 10000,
+ .max_sampling_rate = 500000,
+ .wait_init_sequence = true,
+ .bat_sense_sup = true,
+ .scaler_bit_width = 16,
+ .num_channels = 8,
+ .trim_locate = &ast2600_adc1_trim,
+};
+
+static const struct of_device_id aspeed_adc_matches[] = {
+ { .compatible = "aspeed,ast2400-adc", .data = &ast2400_model_data },
+ { .compatible = "aspeed,ast2500-adc", .data = &ast2500_model_data },
+ { .compatible = "aspeed,ast2600-adc0", .data = &ast2600_adc0_model_data },
+ { .compatible = "aspeed,ast2600-adc1", .data = &ast2600_adc1_model_data },
+ {},
+};
+MODULE_DEVICE_TABLE(of, aspeed_adc_matches);
+
+static struct platform_driver aspeed_adc_driver = {
+ .probe = aspeed_adc_probe,
+ .driver = {
+ .name = KBUILD_MODNAME,
+ .of_match_table = aspeed_adc_matches,
+ }
+};
+
+module_platform_driver(aspeed_adc_driver);
+
+MODULE_AUTHOR("Rick Altherr <raltherr@google.com>");
+MODULE_DESCRIPTION("Aspeed AST2400/2500/2600 ADC Driver");
+MODULE_LICENSE("GPL");