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-rw-r--r--drivers/iio/adc/meson_saradc.c1315
1 files changed, 1315 insertions, 0 deletions
diff --git a/drivers/iio/adc/meson_saradc.c b/drivers/iio/adc/meson_saradc.c
new file mode 100644
index 000000000..eb965974e
--- /dev/null
+++ b/drivers/iio/adc/meson_saradc.c
@@ -0,0 +1,1315 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Amlogic Meson Successive Approximation Register (SAR) A/D Converter
+ *
+ * Copyright (C) 2017 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/iio/iio.h>
+#include <linux/module.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/mfd/syscon.h>
+
+#define MESON_SAR_ADC_REG0 0x00
+ #define MESON_SAR_ADC_REG0_PANEL_DETECT BIT(31)
+ #define MESON_SAR_ADC_REG0_BUSY_MASK GENMASK(30, 28)
+ #define MESON_SAR_ADC_REG0_DELTA_BUSY BIT(30)
+ #define MESON_SAR_ADC_REG0_AVG_BUSY BIT(29)
+ #define MESON_SAR_ADC_REG0_SAMPLE_BUSY BIT(28)
+ #define MESON_SAR_ADC_REG0_FIFO_FULL BIT(27)
+ #define MESON_SAR_ADC_REG0_FIFO_EMPTY BIT(26)
+ #define MESON_SAR_ADC_REG0_FIFO_COUNT_MASK GENMASK(25, 21)
+ #define MESON_SAR_ADC_REG0_ADC_BIAS_CTRL_MASK GENMASK(20, 19)
+ #define MESON_SAR_ADC_REG0_CURR_CHAN_ID_MASK GENMASK(18, 16)
+ #define MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL BIT(15)
+ #define MESON_SAR_ADC_REG0_SAMPLING_STOP BIT(14)
+ #define MESON_SAR_ADC_REG0_CHAN_DELTA_EN_MASK GENMASK(13, 12)
+ #define MESON_SAR_ADC_REG0_DETECT_IRQ_POL BIT(10)
+ #define MESON_SAR_ADC_REG0_DETECT_IRQ_EN BIT(9)
+ #define MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK GENMASK(8, 4)
+ #define MESON_SAR_ADC_REG0_FIFO_IRQ_EN BIT(3)
+ #define MESON_SAR_ADC_REG0_SAMPLING_START BIT(2)
+ #define MESON_SAR_ADC_REG0_CONTINUOUS_EN BIT(1)
+ #define MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE BIT(0)
+
+#define MESON_SAR_ADC_CHAN_LIST 0x04
+ #define MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK GENMASK(26, 24)
+ #define MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(_chan) \
+ (GENMASK(2, 0) << ((_chan) * 3))
+
+#define MESON_SAR_ADC_AVG_CNTL 0x08
+ #define MESON_SAR_ADC_AVG_CNTL_AVG_MODE_SHIFT(_chan) \
+ (16 + ((_chan) * 2))
+ #define MESON_SAR_ADC_AVG_CNTL_AVG_MODE_MASK(_chan) \
+ (GENMASK(17, 16) << ((_chan) * 2))
+ #define MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_SHIFT(_chan) \
+ (0 + ((_chan) * 2))
+ #define MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_MASK(_chan) \
+ (GENMASK(1, 0) << ((_chan) * 2))
+
+#define MESON_SAR_ADC_REG3 0x0c
+ #define MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY BIT(31)
+ #define MESON_SAR_ADC_REG3_CLK_EN BIT(30)
+ #define MESON_SAR_ADC_REG3_BL30_INITIALIZED BIT(28)
+ #define MESON_SAR_ADC_REG3_CTRL_CONT_RING_COUNTER_EN BIT(27)
+ #define MESON_SAR_ADC_REG3_CTRL_SAMPLING_CLOCK_PHASE BIT(26)
+ #define MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK GENMASK(25, 23)
+ #define MESON_SAR_ADC_REG3_DETECT_EN BIT(22)
+ #define MESON_SAR_ADC_REG3_ADC_EN BIT(21)
+ #define MESON_SAR_ADC_REG3_PANEL_DETECT_COUNT_MASK GENMASK(20, 18)
+ #define MESON_SAR_ADC_REG3_PANEL_DETECT_FILTER_TB_MASK GENMASK(17, 16)
+ #define MESON_SAR_ADC_REG3_ADC_CLK_DIV_SHIFT 10
+ #define MESON_SAR_ADC_REG3_ADC_CLK_DIV_WIDTH 6
+ #define MESON_SAR_ADC_REG3_BLOCK_DLY_SEL_MASK GENMASK(9, 8)
+ #define MESON_SAR_ADC_REG3_BLOCK_DLY_MASK GENMASK(7, 0)
+
+#define MESON_SAR_ADC_DELAY 0x10
+ #define MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK GENMASK(25, 24)
+ #define MESON_SAR_ADC_DELAY_BL30_BUSY BIT(15)
+ #define MESON_SAR_ADC_DELAY_KERNEL_BUSY BIT(14)
+ #define MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK GENMASK(23, 16)
+ #define MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK GENMASK(9, 8)
+ #define MESON_SAR_ADC_DELAY_SAMPLE_DLY_CNT_MASK GENMASK(7, 0)
+
+#define MESON_SAR_ADC_LAST_RD 0x14
+ #define MESON_SAR_ADC_LAST_RD_LAST_CHANNEL1_MASK GENMASK(23, 16)
+ #define MESON_SAR_ADC_LAST_RD_LAST_CHANNEL0_MASK GENMASK(9, 0)
+
+#define MESON_SAR_ADC_FIFO_RD 0x18
+ #define MESON_SAR_ADC_FIFO_RD_CHAN_ID_MASK GENMASK(14, 12)
+ #define MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK GENMASK(11, 0)
+
+#define MESON_SAR_ADC_AUX_SW 0x1c
+ #define MESON_SAR_ADC_AUX_SW_MUX_SEL_CHAN_SHIFT(_chan) \
+ (8 + (((_chan) - 2) * 3))
+ #define MESON_SAR_ADC_AUX_SW_VREF_P_MUX BIT(6)
+ #define MESON_SAR_ADC_AUX_SW_VREF_N_MUX BIT(5)
+ #define MESON_SAR_ADC_AUX_SW_MODE_SEL BIT(4)
+ #define MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW BIT(3)
+ #define MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW BIT(2)
+ #define MESON_SAR_ADC_AUX_SW_YM_DRIVE_SW BIT(1)
+ #define MESON_SAR_ADC_AUX_SW_XM_DRIVE_SW BIT(0)
+
+#define MESON_SAR_ADC_CHAN_10_SW 0x20
+ #define MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK GENMASK(25, 23)
+ #define MESON_SAR_ADC_CHAN_10_SW_CHAN1_VREF_P_MUX BIT(22)
+ #define MESON_SAR_ADC_CHAN_10_SW_CHAN1_VREF_N_MUX BIT(21)
+ #define MESON_SAR_ADC_CHAN_10_SW_CHAN1_MODE_SEL BIT(20)
+ #define MESON_SAR_ADC_CHAN_10_SW_CHAN1_YP_DRIVE_SW BIT(19)
+ #define MESON_SAR_ADC_CHAN_10_SW_CHAN1_XP_DRIVE_SW BIT(18)
+ #define MESON_SAR_ADC_CHAN_10_SW_CHAN1_YM_DRIVE_SW BIT(17)
+ #define MESON_SAR_ADC_CHAN_10_SW_CHAN1_XM_DRIVE_SW BIT(16)
+ #define MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK GENMASK(9, 7)
+ #define MESON_SAR_ADC_CHAN_10_SW_CHAN0_VREF_P_MUX BIT(6)
+ #define MESON_SAR_ADC_CHAN_10_SW_CHAN0_VREF_N_MUX BIT(5)
+ #define MESON_SAR_ADC_CHAN_10_SW_CHAN0_MODE_SEL BIT(4)
+ #define MESON_SAR_ADC_CHAN_10_SW_CHAN0_YP_DRIVE_SW BIT(3)
+ #define MESON_SAR_ADC_CHAN_10_SW_CHAN0_XP_DRIVE_SW BIT(2)
+ #define MESON_SAR_ADC_CHAN_10_SW_CHAN0_YM_DRIVE_SW BIT(1)
+ #define MESON_SAR_ADC_CHAN_10_SW_CHAN0_XM_DRIVE_SW BIT(0)
+
+#define MESON_SAR_ADC_DETECT_IDLE_SW 0x24
+ #define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_SW_EN BIT(26)
+ #define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK GENMASK(25, 23)
+ #define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_VREF_P_MUX BIT(22)
+ #define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_VREF_N_MUX BIT(21)
+ #define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MODE_SEL BIT(20)
+ #define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_YP_DRIVE_SW BIT(19)
+ #define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_XP_DRIVE_SW BIT(18)
+ #define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_YM_DRIVE_SW BIT(17)
+ #define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_XM_DRIVE_SW BIT(16)
+ #define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK GENMASK(9, 7)
+ #define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_VREF_P_MUX BIT(6)
+ #define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_VREF_N_MUX BIT(5)
+ #define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MODE_SEL BIT(4)
+ #define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_YP_DRIVE_SW BIT(3)
+ #define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_XP_DRIVE_SW BIT(2)
+ #define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_YM_DRIVE_SW BIT(1)
+ #define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_XM_DRIVE_SW BIT(0)
+
+#define MESON_SAR_ADC_DELTA_10 0x28
+ #define MESON_SAR_ADC_DELTA_10_TEMP_SEL BIT(27)
+ #define MESON_SAR_ADC_DELTA_10_TS_REVE1 BIT(26)
+ #define MESON_SAR_ADC_DELTA_10_CHAN1_DELTA_VALUE_MASK GENMASK(25, 16)
+ #define MESON_SAR_ADC_DELTA_10_TS_REVE0 BIT(15)
+ #define MESON_SAR_ADC_DELTA_10_TS_C_MASK GENMASK(14, 11)
+ #define MESON_SAR_ADC_DELTA_10_TS_VBG_EN BIT(10)
+ #define MESON_SAR_ADC_DELTA_10_CHAN0_DELTA_VALUE_MASK GENMASK(9, 0)
+
+/*
+ * NOTE: registers from here are undocumented (the vendor Linux kernel driver
+ * and u-boot source served as reference). These only seem to be relevant on
+ * GXBB and newer.
+ */
+#define MESON_SAR_ADC_REG11 0x2c
+ #define MESON_SAR_ADC_REG11_BANDGAP_EN BIT(13)
+
+#define MESON_SAR_ADC_REG13 0x34
+ #define MESON_SAR_ADC_REG13_12BIT_CALIBRATION_MASK GENMASK(13, 8)
+
+#define MESON_SAR_ADC_MAX_FIFO_SIZE 32
+#define MESON_SAR_ADC_TIMEOUT 100 /* ms */
+#define MESON_SAR_ADC_VOLTAGE_AND_TEMP_CHANNEL 6
+#define MESON_SAR_ADC_TEMP_OFFSET 27
+
+/* temperature sensor calibration information in eFuse */
+#define MESON_SAR_ADC_EFUSE_BYTES 4
+#define MESON_SAR_ADC_EFUSE_BYTE3_UPPER_ADC_VAL GENMASK(6, 0)
+#define MESON_SAR_ADC_EFUSE_BYTE3_IS_CALIBRATED BIT(7)
+
+#define MESON_HHI_DPLL_TOP_0 0x318
+#define MESON_HHI_DPLL_TOP_0_TSC_BIT4 BIT(9)
+
+/* for use with IIO_VAL_INT_PLUS_MICRO */
+#define MILLION 1000000
+
+#define MESON_SAR_ADC_CHAN(_chan) { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .channel = _chan, \
+ .address = _chan, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_AVERAGE_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_CALIBBIAS) | \
+ BIT(IIO_CHAN_INFO_CALIBSCALE), \
+ .datasheet_name = "SAR_ADC_CH"#_chan, \
+}
+
+#define MESON_SAR_ADC_TEMP_CHAN(_chan) { \
+ .type = IIO_TEMP, \
+ .channel = _chan, \
+ .address = MESON_SAR_ADC_VOLTAGE_AND_TEMP_CHANNEL, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_AVERAGE_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) | \
+ BIT(IIO_CHAN_INFO_SCALE), \
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_CALIBBIAS) | \
+ BIT(IIO_CHAN_INFO_CALIBSCALE), \
+ .datasheet_name = "TEMP_SENSOR", \
+}
+
+static const struct iio_chan_spec meson_sar_adc_iio_channels[] = {
+ MESON_SAR_ADC_CHAN(0),
+ MESON_SAR_ADC_CHAN(1),
+ MESON_SAR_ADC_CHAN(2),
+ MESON_SAR_ADC_CHAN(3),
+ MESON_SAR_ADC_CHAN(4),
+ MESON_SAR_ADC_CHAN(5),
+ MESON_SAR_ADC_CHAN(6),
+ MESON_SAR_ADC_CHAN(7),
+ IIO_CHAN_SOFT_TIMESTAMP(8),
+};
+
+static const struct iio_chan_spec meson_sar_adc_and_temp_iio_channels[] = {
+ MESON_SAR_ADC_CHAN(0),
+ MESON_SAR_ADC_CHAN(1),
+ MESON_SAR_ADC_CHAN(2),
+ MESON_SAR_ADC_CHAN(3),
+ MESON_SAR_ADC_CHAN(4),
+ MESON_SAR_ADC_CHAN(5),
+ MESON_SAR_ADC_CHAN(6),
+ MESON_SAR_ADC_CHAN(7),
+ MESON_SAR_ADC_TEMP_CHAN(8),
+ IIO_CHAN_SOFT_TIMESTAMP(9),
+};
+
+enum meson_sar_adc_avg_mode {
+ NO_AVERAGING = 0x0,
+ MEAN_AVERAGING = 0x1,
+ MEDIAN_AVERAGING = 0x2,
+};
+
+enum meson_sar_adc_num_samples {
+ ONE_SAMPLE = 0x0,
+ TWO_SAMPLES = 0x1,
+ FOUR_SAMPLES = 0x2,
+ EIGHT_SAMPLES = 0x3,
+};
+
+enum meson_sar_adc_chan7_mux_sel {
+ CHAN7_MUX_VSS = 0x0,
+ CHAN7_MUX_VDD_DIV4 = 0x1,
+ CHAN7_MUX_VDD_DIV2 = 0x2,
+ CHAN7_MUX_VDD_MUL3_DIV4 = 0x3,
+ CHAN7_MUX_VDD = 0x4,
+ CHAN7_MUX_CH7_INPUT = 0x7,
+};
+
+struct meson_sar_adc_param {
+ bool has_bl30_integration;
+ unsigned long clock_rate;
+ u32 bandgap_reg;
+ unsigned int resolution;
+ const struct regmap_config *regmap_config;
+ u8 temperature_trimming_bits;
+ unsigned int temperature_multiplier;
+ unsigned int temperature_divider;
+};
+
+struct meson_sar_adc_data {
+ const struct meson_sar_adc_param *param;
+ const char *name;
+};
+
+struct meson_sar_adc_priv {
+ struct regmap *regmap;
+ struct regulator *vref;
+ const struct meson_sar_adc_param *param;
+ struct clk *clkin;
+ struct clk *core_clk;
+ struct clk *adc_sel_clk;
+ struct clk *adc_clk;
+ struct clk_gate clk_gate;
+ struct clk *adc_div_clk;
+ struct clk_divider clk_div;
+ struct completion done;
+ int calibbias;
+ int calibscale;
+ struct regmap *tsc_regmap;
+ bool temperature_sensor_calibrated;
+ u8 temperature_sensor_coefficient;
+ u16 temperature_sensor_adc_val;
+};
+
+static const struct regmap_config meson_sar_adc_regmap_config_gxbb = {
+ .reg_bits = 8,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .max_register = MESON_SAR_ADC_REG13,
+};
+
+static const struct regmap_config meson_sar_adc_regmap_config_meson8 = {
+ .reg_bits = 8,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .max_register = MESON_SAR_ADC_DELTA_10,
+};
+
+static unsigned int meson_sar_adc_get_fifo_count(struct iio_dev *indio_dev)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ u32 regval;
+
+ regmap_read(priv->regmap, MESON_SAR_ADC_REG0, &regval);
+
+ return FIELD_GET(MESON_SAR_ADC_REG0_FIFO_COUNT_MASK, regval);
+}
+
+static int meson_sar_adc_calib_val(struct iio_dev *indio_dev, int val)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ int tmp;
+
+ /* use val_calib = scale * val_raw + offset calibration function */
+ tmp = div_s64((s64)val * priv->calibscale, MILLION) + priv->calibbias;
+
+ return clamp(tmp, 0, (1 << priv->param->resolution) - 1);
+}
+
+static int meson_sar_adc_wait_busy_clear(struct iio_dev *indio_dev)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ int val;
+
+ /*
+ * NOTE: we need a small delay before reading the status, otherwise
+ * the sample engine may not have started internally (which would
+ * seem to us that sampling is already finished).
+ */
+ udelay(1);
+ return regmap_read_poll_timeout_atomic(priv->regmap, MESON_SAR_ADC_REG0, val,
+ !FIELD_GET(MESON_SAR_ADC_REG0_BUSY_MASK, val),
+ 1, 10000);
+}
+
+static int meson_sar_adc_read_raw_sample(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ int *val)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ struct device *dev = indio_dev->dev.parent;
+ int regval, fifo_chan, fifo_val, count;
+
+ if (!wait_for_completion_timeout(&priv->done,
+ msecs_to_jiffies(MESON_SAR_ADC_TIMEOUT)))
+ return -ETIMEDOUT;
+
+ count = meson_sar_adc_get_fifo_count(indio_dev);
+ if (count != 1) {
+ dev_err(dev, "ADC FIFO has %d element(s) instead of one\n", count);
+ return -EINVAL;
+ }
+
+ regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, &regval);
+ fifo_chan = FIELD_GET(MESON_SAR_ADC_FIFO_RD_CHAN_ID_MASK, regval);
+ if (fifo_chan != chan->address) {
+ dev_err(dev, "ADC FIFO entry belongs to channel %d instead of %lu\n",
+ fifo_chan, chan->address);
+ return -EINVAL;
+ }
+
+ fifo_val = FIELD_GET(MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK, regval);
+ fifo_val &= GENMASK(priv->param->resolution - 1, 0);
+ *val = meson_sar_adc_calib_val(indio_dev, fifo_val);
+
+ return 0;
+}
+
+static void meson_sar_adc_set_averaging(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ enum meson_sar_adc_avg_mode mode,
+ enum meson_sar_adc_num_samples samples)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ int val, address = chan->address;
+
+ val = samples << MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_SHIFT(address);
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_AVG_CNTL,
+ MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_MASK(address),
+ val);
+
+ val = mode << MESON_SAR_ADC_AVG_CNTL_AVG_MODE_SHIFT(address);
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_AVG_CNTL,
+ MESON_SAR_ADC_AVG_CNTL_AVG_MODE_MASK(address), val);
+}
+
+static void meson_sar_adc_enable_channel(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ u32 regval;
+
+ /*
+ * the SAR ADC engine allows sampling multiple channels at the same
+ * time. to keep it simple we're only working with one *internal*
+ * channel, which starts counting at index 0 (which means: count = 1).
+ */
+ regval = FIELD_PREP(MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK, 0);
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_LIST,
+ MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK, regval);
+
+ /* map channel index 0 to the channel which we want to read */
+ regval = FIELD_PREP(MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(0),
+ chan->address);
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_LIST,
+ MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(0), regval);
+
+ regval = FIELD_PREP(MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK,
+ chan->address);
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_DETECT_IDLE_SW,
+ MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK,
+ regval);
+
+ regval = FIELD_PREP(MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK,
+ chan->address);
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_DETECT_IDLE_SW,
+ MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK,
+ regval);
+
+ if (chan->address == MESON_SAR_ADC_VOLTAGE_AND_TEMP_CHANNEL) {
+ if (chan->type == IIO_TEMP)
+ regval = MESON_SAR_ADC_DELTA_10_TEMP_SEL;
+ else
+ regval = 0;
+
+ regmap_update_bits(priv->regmap,
+ MESON_SAR_ADC_DELTA_10,
+ MESON_SAR_ADC_DELTA_10_TEMP_SEL, regval);
+ }
+}
+
+static void meson_sar_adc_set_chan7_mux(struct iio_dev *indio_dev,
+ enum meson_sar_adc_chan7_mux_sel sel)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ u32 regval;
+
+ regval = FIELD_PREP(MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK, sel);
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
+ MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK, regval);
+
+ usleep_range(10, 20);
+}
+
+static void meson_sar_adc_start_sample_engine(struct iio_dev *indio_dev)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+
+ reinit_completion(&priv->done);
+
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+ MESON_SAR_ADC_REG0_FIFO_IRQ_EN,
+ MESON_SAR_ADC_REG0_FIFO_IRQ_EN);
+
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+ MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE,
+ MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE);
+
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+ MESON_SAR_ADC_REG0_SAMPLING_START,
+ MESON_SAR_ADC_REG0_SAMPLING_START);
+}
+
+static void meson_sar_adc_stop_sample_engine(struct iio_dev *indio_dev)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+ MESON_SAR_ADC_REG0_FIFO_IRQ_EN, 0);
+
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+ MESON_SAR_ADC_REG0_SAMPLING_STOP,
+ MESON_SAR_ADC_REG0_SAMPLING_STOP);
+
+ /* wait until all modules are stopped */
+ meson_sar_adc_wait_busy_clear(indio_dev);
+
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+ MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE, 0);
+}
+
+static int meson_sar_adc_lock(struct iio_dev *indio_dev)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ int val, ret;
+
+ mutex_lock(&indio_dev->mlock);
+
+ if (priv->param->has_bl30_integration) {
+ /* prevent BL30 from using the SAR ADC while we are using it */
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
+ MESON_SAR_ADC_DELAY_KERNEL_BUSY,
+ MESON_SAR_ADC_DELAY_KERNEL_BUSY);
+
+ udelay(1);
+
+ /*
+ * wait until BL30 releases it's lock (so we can use the SAR
+ * ADC)
+ */
+ ret = regmap_read_poll_timeout_atomic(priv->regmap, MESON_SAR_ADC_DELAY, val,
+ !(val & MESON_SAR_ADC_DELAY_BL30_BUSY),
+ 1, 10000);
+ if (ret) {
+ mutex_unlock(&indio_dev->mlock);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static void meson_sar_adc_unlock(struct iio_dev *indio_dev)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+
+ if (priv->param->has_bl30_integration)
+ /* allow BL30 to use the SAR ADC again */
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
+ MESON_SAR_ADC_DELAY_KERNEL_BUSY, 0);
+
+ mutex_unlock(&indio_dev->mlock);
+}
+
+static void meson_sar_adc_clear_fifo(struct iio_dev *indio_dev)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ unsigned int count, tmp;
+
+ for (count = 0; count < MESON_SAR_ADC_MAX_FIFO_SIZE; count++) {
+ if (!meson_sar_adc_get_fifo_count(indio_dev))
+ break;
+
+ regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, &tmp);
+ }
+}
+
+static int meson_sar_adc_get_sample(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ enum meson_sar_adc_avg_mode avg_mode,
+ enum meson_sar_adc_num_samples avg_samples,
+ int *val)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ struct device *dev = indio_dev->dev.parent;
+ int ret;
+
+ if (chan->type == IIO_TEMP && !priv->temperature_sensor_calibrated)
+ return -ENOTSUPP;
+
+ ret = meson_sar_adc_lock(indio_dev);
+ if (ret)
+ return ret;
+
+ /* clear the FIFO to make sure we're not reading old values */
+ meson_sar_adc_clear_fifo(indio_dev);
+
+ meson_sar_adc_set_averaging(indio_dev, chan, avg_mode, avg_samples);
+
+ meson_sar_adc_enable_channel(indio_dev, chan);
+
+ meson_sar_adc_start_sample_engine(indio_dev);
+ ret = meson_sar_adc_read_raw_sample(indio_dev, chan, val);
+ meson_sar_adc_stop_sample_engine(indio_dev);
+
+ meson_sar_adc_unlock(indio_dev);
+
+ if (ret) {
+ dev_warn(dev, "failed to read sample for channel %lu: %d\n",
+ chan->address, ret);
+ return ret;
+ }
+
+ return IIO_VAL_INT;
+}
+
+static int meson_sar_adc_iio_info_read_raw(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ int *val, int *val2, long mask)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ struct device *dev = indio_dev->dev.parent;
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ return meson_sar_adc_get_sample(indio_dev, chan, NO_AVERAGING,
+ ONE_SAMPLE, val);
+
+ case IIO_CHAN_INFO_AVERAGE_RAW:
+ return meson_sar_adc_get_sample(indio_dev, chan,
+ MEAN_AVERAGING, EIGHT_SAMPLES,
+ val);
+
+ case IIO_CHAN_INFO_SCALE:
+ if (chan->type == IIO_VOLTAGE) {
+ ret = regulator_get_voltage(priv->vref);
+ if (ret < 0) {
+ dev_err(dev, "failed to get vref voltage: %d\n", ret);
+ return ret;
+ }
+
+ *val = ret / 1000;
+ *val2 = priv->param->resolution;
+ return IIO_VAL_FRACTIONAL_LOG2;
+ } else if (chan->type == IIO_TEMP) {
+ /* SoC specific multiplier and divider */
+ *val = priv->param->temperature_multiplier;
+ *val2 = priv->param->temperature_divider;
+
+ /* celsius to millicelsius */
+ *val *= 1000;
+
+ return IIO_VAL_FRACTIONAL;
+ } else {
+ return -EINVAL;
+ }
+
+ case IIO_CHAN_INFO_CALIBBIAS:
+ *val = priv->calibbias;
+ return IIO_VAL_INT;
+
+ case IIO_CHAN_INFO_CALIBSCALE:
+ *val = priv->calibscale / MILLION;
+ *val2 = priv->calibscale % MILLION;
+ return IIO_VAL_INT_PLUS_MICRO;
+
+ case IIO_CHAN_INFO_OFFSET:
+ *val = DIV_ROUND_CLOSEST(MESON_SAR_ADC_TEMP_OFFSET *
+ priv->param->temperature_divider,
+ priv->param->temperature_multiplier);
+ *val -= priv->temperature_sensor_adc_val;
+ return IIO_VAL_INT;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static int meson_sar_adc_clk_init(struct iio_dev *indio_dev,
+ void __iomem *base)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ struct device *dev = indio_dev->dev.parent;
+ struct clk_init_data init;
+ const char *clk_parents[1];
+
+ init.name = devm_kasprintf(dev, GFP_KERNEL, "%s#adc_div", dev_name(dev));
+ if (!init.name)
+ return -ENOMEM;
+
+ init.flags = 0;
+ init.ops = &clk_divider_ops;
+ clk_parents[0] = __clk_get_name(priv->clkin);
+ init.parent_names = clk_parents;
+ init.num_parents = 1;
+
+ priv->clk_div.reg = base + MESON_SAR_ADC_REG3;
+ priv->clk_div.shift = MESON_SAR_ADC_REG3_ADC_CLK_DIV_SHIFT;
+ priv->clk_div.width = MESON_SAR_ADC_REG3_ADC_CLK_DIV_WIDTH;
+ priv->clk_div.hw.init = &init;
+ priv->clk_div.flags = 0;
+
+ priv->adc_div_clk = devm_clk_register(dev, &priv->clk_div.hw);
+ if (WARN_ON(IS_ERR(priv->adc_div_clk)))
+ return PTR_ERR(priv->adc_div_clk);
+
+ init.name = devm_kasprintf(dev, GFP_KERNEL, "%s#adc_en", dev_name(dev));
+ if (!init.name)
+ return -ENOMEM;
+
+ init.flags = CLK_SET_RATE_PARENT;
+ init.ops = &clk_gate_ops;
+ clk_parents[0] = __clk_get_name(priv->adc_div_clk);
+ init.parent_names = clk_parents;
+ init.num_parents = 1;
+
+ priv->clk_gate.reg = base + MESON_SAR_ADC_REG3;
+ priv->clk_gate.bit_idx = __ffs(MESON_SAR_ADC_REG3_CLK_EN);
+ priv->clk_gate.hw.init = &init;
+
+ priv->adc_clk = devm_clk_register(dev, &priv->clk_gate.hw);
+ if (WARN_ON(IS_ERR(priv->adc_clk)))
+ return PTR_ERR(priv->adc_clk);
+
+ return 0;
+}
+
+static int meson_sar_adc_temp_sensor_init(struct iio_dev *indio_dev)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ u8 *buf, trimming_bits, trimming_mask, upper_adc_val;
+ struct device *dev = indio_dev->dev.parent;
+ struct nvmem_cell *temperature_calib;
+ size_t read_len;
+ int ret;
+
+ temperature_calib = devm_nvmem_cell_get(dev, "temperature_calib");
+ if (IS_ERR(temperature_calib)) {
+ ret = PTR_ERR(temperature_calib);
+
+ /*
+ * leave the temperature sensor disabled if no calibration data
+ * was passed via nvmem-cells.
+ */
+ if (ret == -ENODEV)
+ return 0;
+
+ return dev_err_probe(dev, ret, "failed to get temperature_calib cell\n");
+ }
+
+ priv->tsc_regmap = syscon_regmap_lookup_by_phandle(dev->of_node, "amlogic,hhi-sysctrl");
+ if (IS_ERR(priv->tsc_regmap))
+ return dev_err_probe(dev, PTR_ERR(priv->tsc_regmap),
+ "failed to get amlogic,hhi-sysctrl regmap\n");
+
+ read_len = MESON_SAR_ADC_EFUSE_BYTES;
+ buf = nvmem_cell_read(temperature_calib, &read_len);
+ if (IS_ERR(buf))
+ return dev_err_probe(dev, PTR_ERR(buf), "failed to read temperature_calib cell\n");
+ if (read_len != MESON_SAR_ADC_EFUSE_BYTES) {
+ kfree(buf);
+ return dev_err_probe(dev, -EINVAL, "invalid read size of temperature_calib cell\n");
+ }
+
+ trimming_bits = priv->param->temperature_trimming_bits;
+ trimming_mask = BIT(trimming_bits) - 1;
+
+ priv->temperature_sensor_calibrated =
+ buf[3] & MESON_SAR_ADC_EFUSE_BYTE3_IS_CALIBRATED;
+ priv->temperature_sensor_coefficient = buf[2] & trimming_mask;
+
+ upper_adc_val = FIELD_GET(MESON_SAR_ADC_EFUSE_BYTE3_UPPER_ADC_VAL,
+ buf[3]);
+
+ priv->temperature_sensor_adc_val = buf[2];
+ priv->temperature_sensor_adc_val |= upper_adc_val << BITS_PER_BYTE;
+ priv->temperature_sensor_adc_val >>= trimming_bits;
+
+ kfree(buf);
+
+ return 0;
+}
+
+static int meson_sar_adc_init(struct iio_dev *indio_dev)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ struct device *dev = indio_dev->dev.parent;
+ int regval, i, ret;
+
+ /*
+ * make sure we start at CH7 input since the other muxes are only used
+ * for internal calibration.
+ */
+ meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_CH7_INPUT);
+
+ if (priv->param->has_bl30_integration) {
+ /*
+ * leave sampling delay and the input clocks as configured by
+ * BL30 to make sure BL30 gets the values it expects when
+ * reading the temperature sensor.
+ */
+ regmap_read(priv->regmap, MESON_SAR_ADC_REG3, &regval);
+ if (regval & MESON_SAR_ADC_REG3_BL30_INITIALIZED)
+ return 0;
+ }
+
+ meson_sar_adc_stop_sample_engine(indio_dev);
+
+ /*
+ * disable this bit as seems to be only relevant for Meson6 (based
+ * on the vendor driver), which we don't support at the moment.
+ */
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+ MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL, 0);
+
+ /* disable all channels by default */
+ regmap_write(priv->regmap, MESON_SAR_ADC_CHAN_LIST, 0x0);
+
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
+ MESON_SAR_ADC_REG3_CTRL_SAMPLING_CLOCK_PHASE, 0);
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
+ MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY,
+ MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY);
+
+ /* delay between two samples = (10+1) * 1uS */
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
+ MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
+ FIELD_PREP(MESON_SAR_ADC_DELAY_SAMPLE_DLY_CNT_MASK,
+ 10));
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
+ MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK,
+ FIELD_PREP(MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK,
+ 0));
+
+ /* delay between two samples = (10+1) * 1uS */
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
+ MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
+ FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
+ 10));
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
+ MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK,
+ FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK,
+ 1));
+
+ /*
+ * set up the input channel muxes in MESON_SAR_ADC_CHAN_10_SW
+ * (0 = SAR_ADC_CH0, 1 = SAR_ADC_CH1)
+ */
+ regval = FIELD_PREP(MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK, 0);
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
+ MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK,
+ regval);
+ regval = FIELD_PREP(MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK, 1);
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
+ MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK,
+ regval);
+
+ /*
+ * set up the input channel muxes in MESON_SAR_ADC_AUX_SW
+ * (2 = SAR_ADC_CH2, 3 = SAR_ADC_CH3, ...) and enable
+ * MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW and
+ * MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW like the vendor driver.
+ */
+ regval = 0;
+ for (i = 2; i <= 7; i++)
+ regval |= i << MESON_SAR_ADC_AUX_SW_MUX_SEL_CHAN_SHIFT(i);
+ regval |= MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW;
+ regval |= MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW;
+ regmap_write(priv->regmap, MESON_SAR_ADC_AUX_SW, regval);
+
+ if (priv->temperature_sensor_calibrated) {
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
+ MESON_SAR_ADC_DELTA_10_TS_REVE1,
+ MESON_SAR_ADC_DELTA_10_TS_REVE1);
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
+ MESON_SAR_ADC_DELTA_10_TS_REVE0,
+ MESON_SAR_ADC_DELTA_10_TS_REVE0);
+
+ /*
+ * set bits [3:0] of the TSC (temperature sensor coefficient)
+ * to get the correct values when reading the temperature.
+ */
+ regval = FIELD_PREP(MESON_SAR_ADC_DELTA_10_TS_C_MASK,
+ priv->temperature_sensor_coefficient);
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
+ MESON_SAR_ADC_DELTA_10_TS_C_MASK, regval);
+
+ if (priv->param->temperature_trimming_bits == 5) {
+ if (priv->temperature_sensor_coefficient & BIT(4))
+ regval = MESON_HHI_DPLL_TOP_0_TSC_BIT4;
+ else
+ regval = 0;
+
+ /*
+ * bit [4] (the 5th bit when starting to count at 1)
+ * of the TSC is located in the HHI register area.
+ */
+ regmap_update_bits(priv->tsc_regmap,
+ MESON_HHI_DPLL_TOP_0,
+ MESON_HHI_DPLL_TOP_0_TSC_BIT4,
+ regval);
+ }
+ } else {
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
+ MESON_SAR_ADC_DELTA_10_TS_REVE1, 0);
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
+ MESON_SAR_ADC_DELTA_10_TS_REVE0, 0);
+ }
+
+ ret = clk_set_parent(priv->adc_sel_clk, priv->clkin);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to set adc parent to clkin\n");
+
+ ret = clk_set_rate(priv->adc_clk, priv->param->clock_rate);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to set adc clock rate\n");
+
+ return 0;
+}
+
+static void meson_sar_adc_set_bandgap(struct iio_dev *indio_dev, bool on_off)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ const struct meson_sar_adc_param *param = priv->param;
+ u32 enable_mask;
+
+ if (param->bandgap_reg == MESON_SAR_ADC_REG11)
+ enable_mask = MESON_SAR_ADC_REG11_BANDGAP_EN;
+ else
+ enable_mask = MESON_SAR_ADC_DELTA_10_TS_VBG_EN;
+
+ regmap_update_bits(priv->regmap, param->bandgap_reg, enable_mask,
+ on_off ? enable_mask : 0);
+}
+
+static int meson_sar_adc_hw_enable(struct iio_dev *indio_dev)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ struct device *dev = indio_dev->dev.parent;
+ int ret;
+ u32 regval;
+
+ ret = meson_sar_adc_lock(indio_dev);
+ if (ret)
+ goto err_lock;
+
+ ret = regulator_enable(priv->vref);
+ if (ret < 0) {
+ dev_err(dev, "failed to enable vref regulator\n");
+ goto err_vref;
+ }
+
+ ret = clk_prepare_enable(priv->core_clk);
+ if (ret) {
+ dev_err(dev, "failed to enable core clk\n");
+ goto err_core_clk;
+ }
+
+ regval = FIELD_PREP(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, 1);
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
+ MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval);
+
+ meson_sar_adc_set_bandgap(indio_dev, true);
+
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
+ MESON_SAR_ADC_REG3_ADC_EN,
+ MESON_SAR_ADC_REG3_ADC_EN);
+
+ udelay(5);
+
+ ret = clk_prepare_enable(priv->adc_clk);
+ if (ret) {
+ dev_err(dev, "failed to enable adc clk\n");
+ goto err_adc_clk;
+ }
+
+ meson_sar_adc_unlock(indio_dev);
+
+ return 0;
+
+err_adc_clk:
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
+ MESON_SAR_ADC_REG3_ADC_EN, 0);
+ meson_sar_adc_set_bandgap(indio_dev, false);
+ clk_disable_unprepare(priv->core_clk);
+err_core_clk:
+ regulator_disable(priv->vref);
+err_vref:
+ meson_sar_adc_unlock(indio_dev);
+err_lock:
+ return ret;
+}
+
+static int meson_sar_adc_hw_disable(struct iio_dev *indio_dev)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ int ret;
+
+ ret = meson_sar_adc_lock(indio_dev);
+ if (ret)
+ return ret;
+
+ clk_disable_unprepare(priv->adc_clk);
+
+ regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
+ MESON_SAR_ADC_REG3_ADC_EN, 0);
+
+ meson_sar_adc_set_bandgap(indio_dev, false);
+
+ clk_disable_unprepare(priv->core_clk);
+
+ regulator_disable(priv->vref);
+
+ meson_sar_adc_unlock(indio_dev);
+
+ return 0;
+}
+
+static irqreturn_t meson_sar_adc_irq(int irq, void *data)
+{
+ struct iio_dev *indio_dev = data;
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ unsigned int cnt, threshold;
+ u32 regval;
+
+ regmap_read(priv->regmap, MESON_SAR_ADC_REG0, &regval);
+ cnt = FIELD_GET(MESON_SAR_ADC_REG0_FIFO_COUNT_MASK, regval);
+ threshold = FIELD_GET(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval);
+
+ if (cnt < threshold)
+ return IRQ_NONE;
+
+ complete(&priv->done);
+
+ return IRQ_HANDLED;
+}
+
+static int meson_sar_adc_calib(struct iio_dev *indio_dev)
+{
+ struct meson_sar_adc_priv *priv = iio_priv(indio_dev);
+ int ret, nominal0, nominal1, value0, value1;
+
+ /* use points 25% and 75% for calibration */
+ nominal0 = (1 << priv->param->resolution) / 4;
+ nominal1 = (1 << priv->param->resolution) * 3 / 4;
+
+ meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_VDD_DIV4);
+ usleep_range(10, 20);
+ ret = meson_sar_adc_get_sample(indio_dev,
+ &indio_dev->channels[7],
+ MEAN_AVERAGING, EIGHT_SAMPLES, &value0);
+ if (ret < 0)
+ goto out;
+
+ meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_VDD_MUL3_DIV4);
+ usleep_range(10, 20);
+ ret = meson_sar_adc_get_sample(indio_dev,
+ &indio_dev->channels[7],
+ MEAN_AVERAGING, EIGHT_SAMPLES, &value1);
+ if (ret < 0)
+ goto out;
+
+ if (value1 <= value0) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ priv->calibscale = div_s64((nominal1 - nominal0) * (s64)MILLION,
+ value1 - value0);
+ priv->calibbias = nominal0 - div_s64((s64)value0 * priv->calibscale,
+ MILLION);
+ ret = 0;
+out:
+ meson_sar_adc_set_chan7_mux(indio_dev, CHAN7_MUX_CH7_INPUT);
+
+ return ret;
+}
+
+static const struct iio_info meson_sar_adc_iio_info = {
+ .read_raw = meson_sar_adc_iio_info_read_raw,
+};
+
+static const struct meson_sar_adc_param meson_sar_adc_meson8_param = {
+ .has_bl30_integration = false,
+ .clock_rate = 1150000,
+ .bandgap_reg = MESON_SAR_ADC_DELTA_10,
+ .regmap_config = &meson_sar_adc_regmap_config_meson8,
+ .resolution = 10,
+ .temperature_trimming_bits = 4,
+ .temperature_multiplier = 18 * 10000,
+ .temperature_divider = 1024 * 10 * 85,
+};
+
+static const struct meson_sar_adc_param meson_sar_adc_meson8b_param = {
+ .has_bl30_integration = false,
+ .clock_rate = 1150000,
+ .bandgap_reg = MESON_SAR_ADC_DELTA_10,
+ .regmap_config = &meson_sar_adc_regmap_config_meson8,
+ .resolution = 10,
+ .temperature_trimming_bits = 5,
+ .temperature_multiplier = 10,
+ .temperature_divider = 32,
+};
+
+static const struct meson_sar_adc_param meson_sar_adc_gxbb_param = {
+ .has_bl30_integration = true,
+ .clock_rate = 1200000,
+ .bandgap_reg = MESON_SAR_ADC_REG11,
+ .regmap_config = &meson_sar_adc_regmap_config_gxbb,
+ .resolution = 10,
+};
+
+static const struct meson_sar_adc_param meson_sar_adc_gxl_param = {
+ .has_bl30_integration = true,
+ .clock_rate = 1200000,
+ .bandgap_reg = MESON_SAR_ADC_REG11,
+ .regmap_config = &meson_sar_adc_regmap_config_gxbb,
+ .resolution = 12,
+};
+
+static const struct meson_sar_adc_param meson_sar_adc_g12a_param = {
+ .has_bl30_integration = false,
+ .clock_rate = 1200000,
+ .bandgap_reg = MESON_SAR_ADC_REG11,
+ .regmap_config = &meson_sar_adc_regmap_config_gxbb,
+ .resolution = 12,
+};
+
+static const struct meson_sar_adc_data meson_sar_adc_meson8_data = {
+ .param = &meson_sar_adc_meson8_param,
+ .name = "meson-meson8-saradc",
+};
+
+static const struct meson_sar_adc_data meson_sar_adc_meson8b_data = {
+ .param = &meson_sar_adc_meson8b_param,
+ .name = "meson-meson8b-saradc",
+};
+
+static const struct meson_sar_adc_data meson_sar_adc_meson8m2_data = {
+ .param = &meson_sar_adc_meson8b_param,
+ .name = "meson-meson8m2-saradc",
+};
+
+static const struct meson_sar_adc_data meson_sar_adc_gxbb_data = {
+ .param = &meson_sar_adc_gxbb_param,
+ .name = "meson-gxbb-saradc",
+};
+
+static const struct meson_sar_adc_data meson_sar_adc_gxl_data = {
+ .param = &meson_sar_adc_gxl_param,
+ .name = "meson-gxl-saradc",
+};
+
+static const struct meson_sar_adc_data meson_sar_adc_gxm_data = {
+ .param = &meson_sar_adc_gxl_param,
+ .name = "meson-gxm-saradc",
+};
+
+static const struct meson_sar_adc_data meson_sar_adc_axg_data = {
+ .param = &meson_sar_adc_gxl_param,
+ .name = "meson-axg-saradc",
+};
+
+static const struct meson_sar_adc_data meson_sar_adc_g12a_data = {
+ .param = &meson_sar_adc_g12a_param,
+ .name = "meson-g12a-saradc",
+};
+
+static const struct of_device_id meson_sar_adc_of_match[] = {
+ {
+ .compatible = "amlogic,meson8-saradc",
+ .data = &meson_sar_adc_meson8_data,
+ }, {
+ .compatible = "amlogic,meson8b-saradc",
+ .data = &meson_sar_adc_meson8b_data,
+ }, {
+ .compatible = "amlogic,meson8m2-saradc",
+ .data = &meson_sar_adc_meson8m2_data,
+ }, {
+ .compatible = "amlogic,meson-gxbb-saradc",
+ .data = &meson_sar_adc_gxbb_data,
+ }, {
+ .compatible = "amlogic,meson-gxl-saradc",
+ .data = &meson_sar_adc_gxl_data,
+ }, {
+ .compatible = "amlogic,meson-gxm-saradc",
+ .data = &meson_sar_adc_gxm_data,
+ }, {
+ .compatible = "amlogic,meson-axg-saradc",
+ .data = &meson_sar_adc_axg_data,
+ }, {
+ .compatible = "amlogic,meson-g12a-saradc",
+ .data = &meson_sar_adc_g12a_data,
+ },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, meson_sar_adc_of_match);
+
+static int meson_sar_adc_probe(struct platform_device *pdev)
+{
+ const struct meson_sar_adc_data *match_data;
+ struct meson_sar_adc_priv *priv;
+ struct device *dev = &pdev->dev;
+ struct iio_dev *indio_dev;
+ void __iomem *base;
+ int irq, ret;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*priv));
+ if (!indio_dev)
+ return dev_err_probe(dev, -ENOMEM, "failed allocating iio device\n");
+
+ priv = iio_priv(indio_dev);
+ init_completion(&priv->done);
+
+ match_data = of_device_get_match_data(dev);
+ if (!match_data)
+ return dev_err_probe(dev, -ENODEV, "failed to get match data\n");
+
+ priv->param = match_data->param;
+
+ indio_dev->name = match_data->name;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->info = &meson_sar_adc_iio_info;
+
+ base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ priv->regmap = devm_regmap_init_mmio(dev, base, priv->param->regmap_config);
+ if (IS_ERR(priv->regmap))
+ return PTR_ERR(priv->regmap);
+
+ irq = irq_of_parse_and_map(dev->of_node, 0);
+ if (!irq)
+ return -EINVAL;
+
+ ret = devm_request_irq(dev, irq, meson_sar_adc_irq, IRQF_SHARED, dev_name(dev), indio_dev);
+ if (ret)
+ return ret;
+
+ priv->clkin = devm_clk_get(dev, "clkin");
+ if (IS_ERR(priv->clkin))
+ return dev_err_probe(dev, PTR_ERR(priv->clkin), "failed to get clkin\n");
+
+ priv->core_clk = devm_clk_get(dev, "core");
+ if (IS_ERR(priv->core_clk))
+ return dev_err_probe(dev, PTR_ERR(priv->core_clk), "failed to get core clk\n");
+
+ priv->adc_clk = devm_clk_get_optional(dev, "adc_clk");
+ if (IS_ERR(priv->adc_clk))
+ return dev_err_probe(dev, PTR_ERR(priv->adc_clk), "failed to get adc clk\n");
+
+ priv->adc_sel_clk = devm_clk_get_optional(dev, "adc_sel");
+ if (IS_ERR(priv->adc_sel_clk))
+ return dev_err_probe(dev, PTR_ERR(priv->adc_sel_clk), "failed to get adc_sel clk\n");
+
+ /* on pre-GXBB SoCs the SAR ADC itself provides the ADC clock: */
+ if (!priv->adc_clk) {
+ ret = meson_sar_adc_clk_init(indio_dev, base);
+ if (ret)
+ return ret;
+ }
+
+ priv->vref = devm_regulator_get(dev, "vref");
+ if (IS_ERR(priv->vref))
+ return dev_err_probe(dev, PTR_ERR(priv->vref), "failed to get vref regulator\n");
+
+ priv->calibscale = MILLION;
+
+ if (priv->param->temperature_trimming_bits) {
+ ret = meson_sar_adc_temp_sensor_init(indio_dev);
+ if (ret)
+ return ret;
+ }
+
+ if (priv->temperature_sensor_calibrated) {
+ indio_dev->channels = meson_sar_adc_and_temp_iio_channels;
+ indio_dev->num_channels =
+ ARRAY_SIZE(meson_sar_adc_and_temp_iio_channels);
+ } else {
+ indio_dev->channels = meson_sar_adc_iio_channels;
+ indio_dev->num_channels =
+ ARRAY_SIZE(meson_sar_adc_iio_channels);
+ }
+
+ ret = meson_sar_adc_init(indio_dev);
+ if (ret)
+ goto err;
+
+ ret = meson_sar_adc_hw_enable(indio_dev);
+ if (ret)
+ goto err;
+
+ ret = meson_sar_adc_calib(indio_dev);
+ if (ret)
+ dev_warn(dev, "calibration failed\n");
+
+ platform_set_drvdata(pdev, indio_dev);
+
+ ret = iio_device_register(indio_dev);
+ if (ret)
+ goto err_hw;
+
+ return 0;
+
+err_hw:
+ meson_sar_adc_hw_disable(indio_dev);
+err:
+ return ret;
+}
+
+static int meson_sar_adc_remove(struct platform_device *pdev)
+{
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+
+ iio_device_unregister(indio_dev);
+
+ return meson_sar_adc_hw_disable(indio_dev);
+}
+
+static int meson_sar_adc_suspend(struct device *dev)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+
+ return meson_sar_adc_hw_disable(indio_dev);
+}
+
+static int meson_sar_adc_resume(struct device *dev)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+
+ return meson_sar_adc_hw_enable(indio_dev);
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(meson_sar_adc_pm_ops,
+ meson_sar_adc_suspend, meson_sar_adc_resume);
+
+static struct platform_driver meson_sar_adc_driver = {
+ .probe = meson_sar_adc_probe,
+ .remove = meson_sar_adc_remove,
+ .driver = {
+ .name = "meson-saradc",
+ .of_match_table = meson_sar_adc_of_match,
+ .pm = pm_sleep_ptr(&meson_sar_adc_pm_ops),
+ },
+};
+
+module_platform_driver(meson_sar_adc_driver);
+
+MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
+MODULE_DESCRIPTION("Amlogic Meson SAR ADC driver");
+MODULE_LICENSE("GPL v2");