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-rw-r--r--drivers/iio/adc/pac1934.c1636
1 files changed, 1636 insertions, 0 deletions
diff --git a/drivers/iio/adc/pac1934.c b/drivers/iio/adc/pac1934.c
new file mode 100644
index 00000000000000..e0c2742da5236f
--- /dev/null
+++ b/drivers/iio/adc/pac1934.c
@@ -0,0 +1,1636 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * IIO driver for PAC1934 Multi-Channel DC Power/Energy Monitor
+ *
+ * Copyright (C) 2017-2024 Microchip Technology Inc. and its subsidiaries
+ *
+ * Author: Bogdan Bolocan <bogdan.bolocan@microchip.com>
+ * Author: Victor Tudose
+ * Author: Marius Cristea <marius.cristea@microchip.com>
+ *
+ * Datasheet for PAC1931, PAC1932, PAC1933 and PAC1934 can be found here:
+ * https://ww1.microchip.com/downloads/aemDocuments/documents/OTH/ProductDocuments/DataSheets/PAC1931-Family-Data-Sheet-DS20005850E.pdf
+ */
+
+#include <linux/acpi.h>
+#include <linux/bitfield.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <asm/unaligned.h>
+
+/*
+ * maximum accumulation time should be (17 * 60 * 1000) around 17 minutes@1024 sps
+ * till PAC1934 accumulation registers starts to saturate
+ */
+#define PAC1934_MAX_RFSH_LIMIT_MS 60000
+/* 50msec is the timeout for validity of the cached registers */
+#define PAC1934_MIN_POLLING_TIME_MS 50
+/*
+ * 1000usec is the minimum wait time for normal conversions when sample
+ * rate doesn't change
+ */
+#define PAC1934_MIN_UPDATE_WAIT_TIME_US 1000
+
+/* 32000mV */
+#define PAC1934_VOLTAGE_MILLIVOLTS_MAX 32000
+/* voltage bits resolution when set for unsigned values */
+#define PAC1934_VOLTAGE_U_RES 16
+/* voltage bits resolution when set for signed values */
+#define PAC1934_VOLTAGE_S_RES 15
+
+/*
+ * max signed value that can be stored on 32 bits and 8 digits fractional value
+ * (2^31 - 1) * 10^8 + 99999999
+ */
+#define PAC_193X_MAX_POWER_ACC 214748364799999999LL
+/*
+ * min signed value that can be stored on 32 bits and 8 digits fractional value
+ * -(2^31) * 10^8 - 99999999
+ */
+#define PAC_193X_MIN_POWER_ACC -214748364899999999LL
+
+#define PAC1934_MAX_NUM_CHANNELS 4
+
+#define PAC1934_MEAS_REG_LEN 76
+#define PAC1934_CTRL_REG_LEN 12
+
+#define PAC1934_DEFAULT_CHIP_SAMP_SPEED_HZ 1024
+
+/* I2C address map */
+#define PAC1934_REFRESH_REG_ADDR 0x00
+#define PAC1934_CTRL_REG_ADDR 0x01
+#define PAC1934_ACC_COUNT_REG_ADDR 0x02
+#define PAC1934_VPOWER_ACC_1_ADDR 0x03
+#define PAC1934_VPOWER_ACC_2_ADDR 0x04
+#define PAC1934_VPOWER_ACC_3_ADDR 0x05
+#define PAC1934_VPOWER_ACC_4_ADDR 0x06
+#define PAC1934_VBUS_1_ADDR 0x07
+#define PAC1934_VBUS_2_ADDR 0x08
+#define PAC1934_VBUS_3_ADDR 0x09
+#define PAC1934_VBUS_4_ADDR 0x0A
+#define PAC1934_VSENSE_1_ADDR 0x0B
+#define PAC1934_VSENSE_2_ADDR 0x0C
+#define PAC1934_VSENSE_3_ADDR 0x0D
+#define PAC1934_VSENSE_4_ADDR 0x0E
+#define PAC1934_VBUS_AVG_1_ADDR 0x0F
+#define PAC1934_VBUS_AVG_2_ADDR 0x10
+#define PAC1934_VBUS_AVG_3_ADDR 0x11
+#define PAC1934_VBUS_AVG_4_ADDR 0x12
+#define PAC1934_VSENSE_AVG_1_ADDR 0x13
+#define PAC1934_VSENSE_AVG_2_ADDR 0x14
+#define PAC1934_VSENSE_AVG_3_ADDR 0x15
+#define PAC1934_VSENSE_AVG_4_ADDR 0x16
+#define PAC1934_VPOWER_1_ADDR 0x17
+#define PAC1934_VPOWER_2_ADDR 0x18
+#define PAC1934_VPOWER_3_ADDR 0x19
+#define PAC1934_VPOWER_4_ADDR 0x1A
+#define PAC1934_REFRESH_V_REG_ADDR 0x1F
+#define PAC1934_CTRL_STAT_REGS_ADDR 0x1C
+#define PAC1934_PID_REG_ADDR 0xFD
+#define PAC1934_MID_REG_ADDR 0xFE
+#define PAC1934_RID_REG_ADDR 0xFF
+
+/* PRODUCT ID REGISTER + MANUFACTURER ID REGISTER + REVISION ID REGISTER */
+#define PAC1934_ID_REG_LEN 3
+#define PAC1934_PID_IDX 0
+#define PAC1934_MID_IDX 1
+#define PAC1934_RID_IDX 2
+
+#define PAC1934_ACPI_GET_NAMES_AND_MOHMS_VALS 1
+#define PAC1934_ACPI_GET_UOHMS_VALS 2
+#define PAC1934_ACPI_GET_BIPOLAR_SETTINGS 4
+#define PAC1934_ACPI_GET_SAMP 5
+
+#define PAC1934_SAMPLE_RATE_SHIFT 6
+
+#define PAC1934_VBUS_SENSE_REG_LEN 2
+#define PAC1934_ACC_REG_LEN 3
+#define PAC1934_VPOWER_REG_LEN 4
+#define PAC1934_VPOWER_ACC_REG_LEN 6
+#define PAC1934_MAX_REGISTER_LENGTH 6
+
+#define PAC1934_CUSTOM_ATTR_FOR_CHANNEL 1
+
+/*
+ * relative offsets when using multi-byte reads/writes even though these
+ * bytes are read one after the other, they are not at adjacent memory
+ * locations within the I2C memory map. The chip can skip some addresses
+ */
+#define PAC1934_CHANNEL_DIS_REG_OFF 0
+#define PAC1934_NEG_PWR_REG_OFF 1
+
+/*
+ * when reading/writing multiple bytes from offset PAC1934_CHANNEL_DIS_REG_OFF,
+ * the chip jumps over the 0x1E (REFRESH_G) and 0x1F (REFRESH_V) offsets
+ */
+#define PAC1934_SLOW_REG_OFF 2
+#define PAC1934_CTRL_ACT_REG_OFF 3
+#define PAC1934_CHANNEL_DIS_ACT_REG_OFF 4
+#define PAC1934_NEG_PWR_ACT_REG_OFF 5
+#define PAC1934_CTRL_LAT_REG_OFF 6
+#define PAC1934_CHANNEL_DIS_LAT_REG_OFF 7
+#define PAC1934_NEG_PWR_LAT_REG_OFF 8
+#define PAC1934_PID_REG_OFF 9
+#define PAC1934_MID_REG_OFF 10
+#define PAC1934_REV_REG_OFF 11
+#define PAC1934_CTRL_STATUS_INFO_LEN 12
+
+#define PAC1934_MID 0x5D
+#define PAC1931_PID 0x58
+#define PAC1932_PID 0x59
+#define PAC1933_PID 0x5A
+#define PAC1934_PID 0x5B
+
+/* Scale constant = (10^3 * 3.2 * 10^9 / 2^28) for mili Watt-second */
+#define PAC1934_SCALE_CONSTANT 11921
+
+#define PAC1934_MAX_VPOWER_RSHIFTED_BY_28B 11921
+#define PAC1934_MAX_VSENSE_RSHIFTED_BY_16B 1525
+
+#define PAC1934_DEV_ATTR(name) (&iio_dev_attr_##name.dev_attr.attr)
+
+#define PAC1934_CRTL_SAMPLE_RATE_MASK GENMASK(7, 6)
+#define PAC1934_CHAN_SLEEP_MASK BIT(5)
+#define PAC1934_CHAN_SLEEP_SET BIT(5)
+#define PAC1934_CHAN_SINGLE_MASK BIT(4)
+#define PAC1934_CHAN_SINGLE_SHOT_SET BIT(4)
+#define PAC1934_CHAN_ALERT_MASK BIT(3)
+#define PAC1934_CHAN_ALERT_EN BIT(3)
+#define PAC1934_CHAN_ALERT_CC_MASK BIT(2)
+#define PAC1934_CHAN_ALERT_CC_EN BIT(2)
+#define PAC1934_CHAN_OVF_ALERT_MASK BIT(1)
+#define PAC1934_CHAN_OVF_ALERT_EN BIT(1)
+#define PAC1934_CHAN_OVF_MASK BIT(0)
+
+#define PAC1934_CHAN_DIS_CH1_OFF_MASK BIT(7)
+#define PAC1934_CHAN_DIS_CH2_OFF_MASK BIT(6)
+#define PAC1934_CHAN_DIS_CH3_OFF_MASK BIT(5)
+#define PAC1934_CHAN_DIS_CH4_OFF_MASK BIT(4)
+#define PAC1934_SMBUS_TIMEOUT_MASK BIT(3)
+#define PAC1934_SMBUS_BYTECOUNT_MASK BIT(2)
+#define PAC1934_SMBUS_NO_SKIP_MASK BIT(1)
+
+#define PAC1934_NEG_PWR_CH1_BIDI_MASK BIT(7)
+#define PAC1934_NEG_PWR_CH2_BIDI_MASK BIT(6)
+#define PAC1934_NEG_PWR_CH3_BIDI_MASK BIT(5)
+#define PAC1934_NEG_PWR_CH4_BIDI_MASK BIT(4)
+#define PAC1934_NEG_PWR_CH1_BIDV_MASK BIT(3)
+#define PAC1934_NEG_PWR_CH2_BIDV_MASK BIT(2)
+#define PAC1934_NEG_PWR_CH3_BIDV_MASK BIT(1)
+#define PAC1934_NEG_PWR_CH4_BIDV_MASK BIT(0)
+
+/*
+ * Universal Unique Identifier (UUID),
+ * 033771E0-1705-47B4-9535-D1BBE14D9A09,
+ * is reserved to Microchip for the PAC1934.
+ */
+#define PAC1934_DSM_UUID "033771E0-1705-47B4-9535-D1BBE14D9A09"
+
+enum pac1934_ids {
+ PAC1931,
+ PAC1932,
+ PAC1933,
+ PAC1934
+};
+
+enum pac1934_samps {
+ PAC1934_SAMP_1024SPS,
+ PAC1934_SAMP_256SPS,
+ PAC1934_SAMP_64SPS,
+ PAC1934_SAMP_8SPS
+};
+
+/*
+ * these indexes are exactly describing the element order within a single
+ * PAC1934 phys channel IIO channel descriptor; see the static const struct
+ * iio_chan_spec pac1934_single_channel[] declaration
+ */
+enum pac1934_ch_idx {
+ PAC1934_CH_ENERGY,
+ PAC1934_CH_POWER,
+ PAC1934_CH_VOLTAGE,
+ PAC1934_CH_CURRENT,
+ PAC1934_CH_VOLTAGE_AVERAGE,
+ PAC1934_CH_CURRENT_AVERAGE
+};
+
+/**
+ * struct pac1934_features - features of a pac1934 instance
+ * @phys_channels: number of physical channels supported by the chip
+ * @name: chip's name
+ */
+struct pac1934_features {
+ u8 phys_channels;
+ const char *name;
+};
+
+struct samp_rate_mapping {
+ u16 samp_rate;
+ u8 shift2value;
+};
+
+static const unsigned int samp_rate_map_tbl[] = {
+ [PAC1934_SAMP_1024SPS] = 1024,
+ [PAC1934_SAMP_256SPS] = 256,
+ [PAC1934_SAMP_64SPS] = 64,
+ [PAC1934_SAMP_8SPS] = 8,
+};
+
+static const struct pac1934_features pac1934_chip_config[] = {
+ [PAC1931] = {
+ .phys_channels = 1,
+ .name = "pac1931",
+ },
+ [PAC1932] = {
+ .phys_channels = 2,
+ .name = "pac1932",
+ },
+ [PAC1933] = {
+ .phys_channels = 3,
+ .name = "pac1933",
+ },
+ [PAC1934] = {
+ .phys_channels = 4,
+ .name = "pac1934",
+ },
+};
+
+/**
+ * struct reg_data - data from the registers
+ * @meas_regs: snapshot of raw measurements registers
+ * @ctrl_regs: snapshot of control registers
+ * @energy_sec_acc: snapshot of energy values
+ * @vpower_acc: accumulated vpower values
+ * @vpower: snapshot of vpower registers
+ * @vbus: snapshot of vbus registers
+ * @vbus_avg: averages of vbus registers
+ * @vsense: snapshot of vsense registers
+ * @vsense_avg: averages of vsense registers
+ * @num_enabled_channels: count of how many chip channels are currently enabled
+ */
+struct reg_data {
+ u8 meas_regs[PAC1934_MEAS_REG_LEN];
+ u8 ctrl_regs[PAC1934_CTRL_REG_LEN];
+ s64 energy_sec_acc[PAC1934_MAX_NUM_CHANNELS];
+ s64 vpower_acc[PAC1934_MAX_NUM_CHANNELS];
+ s32 vpower[PAC1934_MAX_NUM_CHANNELS];
+ s32 vbus[PAC1934_MAX_NUM_CHANNELS];
+ s32 vbus_avg[PAC1934_MAX_NUM_CHANNELS];
+ s32 vsense[PAC1934_MAX_NUM_CHANNELS];
+ s32 vsense_avg[PAC1934_MAX_NUM_CHANNELS];
+ u8 num_enabled_channels;
+};
+
+/**
+ * struct pac1934_chip_info - information about the chip
+ * @client: the i2c-client attached to the device
+ * @lock: synchronize access to driver's state members
+ * @work_chip_rfsh: work queue used for refresh commands
+ * @phys_channels: phys channels count
+ * @active_channels: array of values, true means that channel is active
+ * @enable_energy: array of values, true means that channel energy is measured
+ * @bi_dir: array of bools, true means that channel is bidirectional
+ * @chip_variant: chip variant
+ * @chip_revision: chip revision
+ * @shunts: shunts
+ * @chip_reg_data: chip reg data
+ * @sample_rate_value: sampling frequency
+ * @labels: table with channels labels
+ * @iio_info: iio_info
+ * @tstamp: chip's uptime
+ */
+struct pac1934_chip_info {
+ struct i2c_client *client;
+ struct mutex lock; /* synchronize access to driver's state members */
+ struct delayed_work work_chip_rfsh;
+ u8 phys_channels;
+ bool active_channels[PAC1934_MAX_NUM_CHANNELS];
+ bool enable_energy[PAC1934_MAX_NUM_CHANNELS];
+ bool bi_dir[PAC1934_MAX_NUM_CHANNELS];
+ u8 chip_variant;
+ u8 chip_revision;
+ u32 shunts[PAC1934_MAX_NUM_CHANNELS];
+ struct reg_data chip_reg_data;
+ s32 sample_rate_value;
+ char *labels[PAC1934_MAX_NUM_CHANNELS];
+ struct iio_info iio_info;
+ unsigned long tstamp;
+};
+
+#define TO_PAC1934_CHIP_INFO(d) container_of(d, struct pac1934_chip_info, work_chip_rfsh)
+
+#define PAC1934_VPOWER_ACC_CHANNEL(_index, _si, _address) { \
+ .type = IIO_ENERGY, \
+ .address = (_address), \
+ .indexed = 1, \
+ .channel = (_index), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_SCALE) | \
+ BIT(IIO_CHAN_INFO_ENABLE), \
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .scan_index = (_si), \
+ .scan_type = { \
+ .sign = 'u', \
+ .realbits = 48, \
+ .storagebits = 64, \
+ .endianness = IIO_CPU, \
+ } \
+}
+
+#define PAC1934_VBUS_CHANNEL(_index, _si, _address) { \
+ .type = IIO_VOLTAGE, \
+ .address = (_address), \
+ .indexed = 1, \
+ .channel = (_index), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_SCALE), \
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .scan_index = (_si), \
+ .scan_type = { \
+ .sign = 'u', \
+ .realbits = 16, \
+ .storagebits = 16, \
+ .endianness = IIO_CPU, \
+ } \
+}
+
+#define PAC1934_VBUS_AVG_CHANNEL(_index, _si, _address) { \
+ .type = IIO_VOLTAGE, \
+ .address = (_address), \
+ .indexed = 1, \
+ .channel = (_index), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_AVERAGE_RAW) | \
+ BIT(IIO_CHAN_INFO_SCALE), \
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .scan_index = (_si), \
+ .scan_type = { \
+ .sign = 'u', \
+ .realbits = 16, \
+ .storagebits = 16, \
+ .endianness = IIO_CPU, \
+ } \
+}
+
+#define PAC1934_VSENSE_CHANNEL(_index, _si, _address) { \
+ .type = IIO_CURRENT, \
+ .address = (_address), \
+ .indexed = 1, \
+ .channel = (_index), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_SCALE), \
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .scan_index = (_si), \
+ .scan_type = { \
+ .sign = 'u', \
+ .realbits = 16, \
+ .storagebits = 16, \
+ .endianness = IIO_CPU, \
+ } \
+}
+
+#define PAC1934_VSENSE_AVG_CHANNEL(_index, _si, _address) { \
+ .type = IIO_CURRENT, \
+ .address = (_address), \
+ .indexed = 1, \
+ .channel = (_index), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_AVERAGE_RAW) | \
+ BIT(IIO_CHAN_INFO_SCALE), \
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .scan_index = (_si), \
+ .scan_type = { \
+ .sign = 'u', \
+ .realbits = 16, \
+ .storagebits = 16, \
+ .endianness = IIO_CPU, \
+ } \
+}
+
+#define PAC1934_VPOWER_CHANNEL(_index, _si, _address) { \
+ .type = IIO_POWER, \
+ .address = (_address), \
+ .indexed = 1, \
+ .channel = (_index), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_SCALE), \
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .scan_index = (_si), \
+ .scan_type = { \
+ .sign = 'u', \
+ .realbits = 28, \
+ .storagebits = 32, \
+ .shift = 4, \
+ .endianness = IIO_CPU, \
+ } \
+}
+
+static const struct iio_chan_spec pac1934_single_channel[] = {
+ PAC1934_VPOWER_ACC_CHANNEL(0, 0, PAC1934_VPOWER_ACC_1_ADDR),
+ PAC1934_VPOWER_CHANNEL(0, 0, PAC1934_VPOWER_1_ADDR),
+ PAC1934_VBUS_CHANNEL(0, 0, PAC1934_VBUS_1_ADDR),
+ PAC1934_VSENSE_CHANNEL(0, 0, PAC1934_VSENSE_1_ADDR),
+ PAC1934_VBUS_AVG_CHANNEL(0, 0, PAC1934_VBUS_AVG_1_ADDR),
+ PAC1934_VSENSE_AVG_CHANNEL(0, 0, PAC1934_VSENSE_AVG_1_ADDR),
+};
+
+/* Low-level I2c functions used to transfer up to 76 bytes at once */
+static int pac1934_i2c_read(struct i2c_client *client, u8 reg_addr,
+ void *databuf, u8 len)
+{
+ int ret;
+ struct i2c_msg msgs[2] = {
+ {
+ .addr = client->addr,
+ .len = 1,
+ .buf = (u8 *)&reg_addr,
+ },
+ {
+ .addr = client->addr,
+ .len = len,
+ .buf = databuf,
+ .flags = I2C_M_RD
+ }
+ };
+
+ ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int pac1934_get_samp_rate_idx(struct pac1934_chip_info *info,
+ u32 new_samp_rate)
+{
+ int cnt;
+
+ for (cnt = 0; cnt < ARRAY_SIZE(samp_rate_map_tbl); cnt++)
+ if (new_samp_rate == samp_rate_map_tbl[cnt])
+ return cnt;
+
+ /* not a valid sample rate value */
+ return -EINVAL;
+}
+
+static ssize_t pac1934_shunt_value_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+ struct pac1934_chip_info *info = iio_priv(indio_dev);
+ struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+
+ return sysfs_emit(buf, "%u\n", info->shunts[this_attr->address]);
+}
+
+static ssize_t pac1934_shunt_value_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+ struct pac1934_chip_info *info = iio_priv(indio_dev);
+ struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
+ int sh_val;
+
+ if (kstrtouint(buf, 10, &sh_val)) {
+ dev_err(dev, "Shunt value is not valid\n");
+ return -EINVAL;
+ }
+
+ scoped_guard(mutex, &info->lock)
+ info->shunts[this_attr->address] = sh_val;
+
+ return count;
+}
+
+static int pac1934_read_avail(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *channel,
+ const int **vals, int *type, int *length, long mask)
+{
+ switch (mask) {
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ *type = IIO_VAL_INT;
+ *vals = samp_rate_map_tbl;
+ *length = ARRAY_SIZE(samp_rate_map_tbl);
+ return IIO_AVAIL_LIST;
+ }
+
+ return -EINVAL;
+}
+
+static int pac1934_send_refresh(struct pac1934_chip_info *info,
+ u8 refresh_cmd, u32 wait_time)
+{
+ /* this function only sends REFRESH or REFRESH_V */
+ struct i2c_client *client = info->client;
+ int ret;
+ u8 bidir_reg;
+ bool revision_bug = false;
+
+ if (info->chip_revision == 2 || info->chip_revision == 3) {
+ /*
+ * chip rev 2 and 3 bug workaround
+ * see: PAC1934 Family Data Sheet Errata DS80000836A.pdf
+ */
+ revision_bug = true;
+
+ bidir_reg =
+ FIELD_PREP(PAC1934_NEG_PWR_CH1_BIDI_MASK, info->bi_dir[0]) |
+ FIELD_PREP(PAC1934_NEG_PWR_CH2_BIDI_MASK, info->bi_dir[1]) |
+ FIELD_PREP(PAC1934_NEG_PWR_CH3_BIDI_MASK, info->bi_dir[2]) |
+ FIELD_PREP(PAC1934_NEG_PWR_CH4_BIDI_MASK, info->bi_dir[3]) |
+ FIELD_PREP(PAC1934_NEG_PWR_CH1_BIDV_MASK, info->bi_dir[0]) |
+ FIELD_PREP(PAC1934_NEG_PWR_CH2_BIDV_MASK, info->bi_dir[1]) |
+ FIELD_PREP(PAC1934_NEG_PWR_CH3_BIDV_MASK, info->bi_dir[2]) |
+ FIELD_PREP(PAC1934_NEG_PWR_CH4_BIDV_MASK, info->bi_dir[3]);
+
+ ret = i2c_smbus_write_byte_data(client,
+ PAC1934_CTRL_STAT_REGS_ADDR +
+ PAC1934_NEG_PWR_REG_OFF,
+ bidir_reg);
+ if (ret)
+ return ret;
+ }
+
+ ret = i2c_smbus_write_byte(client, refresh_cmd);
+ if (ret) {
+ dev_err(&client->dev, "%s - cannot send 0x%02X\n",
+ __func__, refresh_cmd);
+ return ret;
+ }
+
+ if (revision_bug) {
+ /*
+ * chip rev 2 and 3 bug workaround - write again the same
+ * register write the updated registers back
+ */
+ ret = i2c_smbus_write_byte_data(client,
+ PAC1934_CTRL_STAT_REGS_ADDR +
+ PAC1934_NEG_PWR_REG_OFF, bidir_reg);
+ if (ret)
+ return ret;
+ }
+
+ /* register data retrieval timestamp */
+ info->tstamp = jiffies;
+
+ /* wait till the data is available */
+ usleep_range(wait_time, wait_time + 100);
+
+ return ret;
+}
+
+static int pac1934_reg_snapshot(struct pac1934_chip_info *info,
+ bool do_refresh, u8 refresh_cmd, u32 wait_time)
+{
+ int ret;
+ struct i2c_client *client = info->client;
+ u8 samp_shift, ctrl_regs_tmp;
+ u8 *offset_reg_data_p;
+ u16 tmp_value;
+ u32 samp_rate, cnt, tmp;
+ s64 curr_energy, inc;
+ u64 tmp_energy;
+ struct reg_data *reg_data;
+
+ guard(mutex)(&info->lock);
+
+ if (do_refresh) {
+ ret = pac1934_send_refresh(info, refresh_cmd, wait_time);
+ if (ret < 0) {
+ dev_err(&client->dev,
+ "%s - cannot send refresh\n",
+ __func__);
+ return ret;
+ }
+ }
+
+ ret = i2c_smbus_read_i2c_block_data(client, PAC1934_CTRL_STAT_REGS_ADDR,
+ PAC1934_CTRL_REG_LEN,
+ (u8 *)info->chip_reg_data.ctrl_regs);
+ if (ret < 0) {
+ dev_err(&client->dev,
+ "%s - cannot read ctrl/status registers\n",
+ __func__);
+ return ret;
+ }
+
+ reg_data = &info->chip_reg_data;
+
+ /* read the data registers */
+ ret = pac1934_i2c_read(client, PAC1934_ACC_COUNT_REG_ADDR,
+ (u8 *)reg_data->meas_regs, PAC1934_MEAS_REG_LEN);
+ if (ret) {
+ dev_err(&client->dev,
+ "%s - cannot read ACC_COUNT register: %d:%d\n",
+ __func__, ret, PAC1934_MEAS_REG_LEN);
+ return ret;
+ }
+
+ /* see how much shift is required by the sample rate */
+ samp_rate = samp_rate_map_tbl[((reg_data->ctrl_regs[PAC1934_CTRL_LAT_REG_OFF]) >> 6)];
+ samp_shift = get_count_order(samp_rate);
+
+ ctrl_regs_tmp = reg_data->ctrl_regs[PAC1934_CHANNEL_DIS_LAT_REG_OFF];
+ offset_reg_data_p = &reg_data->meas_regs[PAC1934_ACC_REG_LEN];
+
+ /* start with VPOWER_ACC */
+ for (cnt = 0; cnt < info->phys_channels; cnt++) {
+ /* check if the channel is active, skip all fields if disabled */
+ if ((ctrl_regs_tmp << cnt) & 0x80)
+ continue;
+
+ /* skip if the energy accumulation is disabled */
+ if (info->enable_energy[cnt]) {
+ curr_energy = info->chip_reg_data.energy_sec_acc[cnt];
+
+ tmp_energy = get_unaligned_be48(offset_reg_data_p);
+
+ if (info->bi_dir[cnt])
+ reg_data->vpower_acc[cnt] = sign_extend64(tmp_energy, 47);
+ else
+ reg_data->vpower_acc[cnt] = tmp_energy;
+
+ /*
+ * compute the scaled to 1 second accumulated energy value;
+ * energy accumulator scaled to 1sec = VPOWER_ACC/2^samp_shift
+ * the chip's sampling rate is 2^samp_shift samples/sec
+ */
+ inc = (reg_data->vpower_acc[cnt] >> samp_shift);
+
+ /* add the power_acc field */
+ curr_energy += inc;
+
+ clamp(curr_energy, PAC_193X_MIN_POWER_ACC, PAC_193X_MAX_POWER_ACC);
+
+ reg_data->energy_sec_acc[cnt] = curr_energy;
+ }
+
+ offset_reg_data_p += PAC1934_VPOWER_ACC_REG_LEN;
+ }
+
+ /* continue with VBUS */
+ for (cnt = 0; cnt < info->phys_channels; cnt++) {
+ if ((ctrl_regs_tmp << cnt) & 0x80)
+ continue;
+
+ tmp_value = get_unaligned_be16(offset_reg_data_p);
+
+ if (info->bi_dir[cnt])
+ reg_data->vbus[cnt] = sign_extend32((u32)(tmp_value), 15);
+ else
+ reg_data->vbus[cnt] = tmp_value;
+
+ offset_reg_data_p += PAC1934_VBUS_SENSE_REG_LEN;
+ }
+
+ /* VSENSE */
+ for (cnt = 0; cnt < info->phys_channels; cnt++) {
+ if ((ctrl_regs_tmp << cnt) & 0x80)
+ continue;
+
+ tmp_value = get_unaligned_be16(offset_reg_data_p);
+
+ if (info->bi_dir[cnt])
+ reg_data->vsense[cnt] = sign_extend32((u32)(tmp_value), 15);
+ else
+ reg_data->vsense[cnt] = tmp_value;
+
+ offset_reg_data_p += PAC1934_VBUS_SENSE_REG_LEN;
+ }
+
+ /* VBUS_AVG */
+ for (cnt = 0; cnt < info->phys_channels; cnt++) {
+ if ((ctrl_regs_tmp << cnt) & 0x80)
+ continue;
+
+ tmp_value = get_unaligned_be16(offset_reg_data_p);
+
+ if (info->bi_dir[cnt])
+ reg_data->vbus_avg[cnt] = sign_extend32((u32)(tmp_value), 15);
+ else
+ reg_data->vbus_avg[cnt] = tmp_value;
+
+ offset_reg_data_p += PAC1934_VBUS_SENSE_REG_LEN;
+ }
+
+ /* VSENSE_AVG */
+ for (cnt = 0; cnt < info->phys_channels; cnt++) {
+ if ((ctrl_regs_tmp << cnt) & 0x80)
+ continue;
+
+ tmp_value = get_unaligned_be16(offset_reg_data_p);
+
+ if (info->bi_dir[cnt])
+ reg_data->vsense_avg[cnt] = sign_extend32((u32)(tmp_value), 15);
+ else
+ reg_data->vsense_avg[cnt] = tmp_value;
+
+ offset_reg_data_p += PAC1934_VBUS_SENSE_REG_LEN;
+ }
+
+ /* VPOWER */
+ for (cnt = 0; cnt < info->phys_channels; cnt++) {
+ if ((ctrl_regs_tmp << cnt) & 0x80)
+ continue;
+
+ tmp = get_unaligned_be32(offset_reg_data_p) >> 4;
+
+ if (info->bi_dir[cnt])
+ reg_data->vpower[cnt] = sign_extend32(tmp, 27);
+ else
+ reg_data->vpower[cnt] = tmp;
+
+ offset_reg_data_p += PAC1934_VPOWER_REG_LEN;
+ }
+
+ return 0;
+}
+
+static int pac1934_retrieve_data(struct pac1934_chip_info *info,
+ u32 wait_time)
+{
+ int ret = 0;
+
+ /*
+ * check if the minimal elapsed time has passed and if so,
+ * re-read the chip, otherwise the cached info is just fine
+ */
+ if (time_after(jiffies, info->tstamp + msecs_to_jiffies(PAC1934_MIN_POLLING_TIME_MS))) {
+ ret = pac1934_reg_snapshot(info, true, PAC1934_REFRESH_REG_ADDR,
+ wait_time);
+
+ /*
+ * Re-schedule the work for the read registers on timeout
+ * (to prevent chip registers saturation)
+ */
+ mod_delayed_work(system_wq, &info->work_chip_rfsh,
+ msecs_to_jiffies(PAC1934_MAX_RFSH_LIMIT_MS));
+ }
+
+ return ret;
+}
+
+static int pac1934_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int *val,
+ int *val2, long mask)
+{
+ struct pac1934_chip_info *info = iio_priv(indio_dev);
+ s64 curr_energy;
+ int ret, channel = chan->channel - 1;
+
+ ret = pac1934_retrieve_data(info, PAC1934_MIN_UPDATE_WAIT_TIME_US);
+ if (ret < 0)
+ return ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ switch (chan->type) {
+ case IIO_VOLTAGE:
+ *val = info->chip_reg_data.vbus[channel];
+ return IIO_VAL_INT;
+ case IIO_CURRENT:
+ *val = info->chip_reg_data.vsense[channel];
+ return IIO_VAL_INT;
+ case IIO_POWER:
+ *val = info->chip_reg_data.vpower[channel];
+ return IIO_VAL_INT;
+ case IIO_ENERGY:
+ curr_energy = info->chip_reg_data.energy_sec_acc[channel];
+ *val = (u32)curr_energy;
+ *val2 = (u32)(curr_energy >> 32);
+ return IIO_VAL_INT_64;
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_AVERAGE_RAW:
+ switch (chan->type) {
+ case IIO_VOLTAGE:
+ *val = info->chip_reg_data.vbus_avg[channel];
+ return IIO_VAL_INT;
+ case IIO_CURRENT:
+ *val = info->chip_reg_data.vsense_avg[channel];
+ return IIO_VAL_INT;
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_SCALE:
+ switch (chan->address) {
+ /* Voltages - scale for millivolts */
+ case PAC1934_VBUS_1_ADDR:
+ case PAC1934_VBUS_2_ADDR:
+ case PAC1934_VBUS_3_ADDR:
+ case PAC1934_VBUS_4_ADDR:
+ case PAC1934_VBUS_AVG_1_ADDR:
+ case PAC1934_VBUS_AVG_2_ADDR:
+ case PAC1934_VBUS_AVG_3_ADDR:
+ case PAC1934_VBUS_AVG_4_ADDR:
+ *val = PAC1934_VOLTAGE_MILLIVOLTS_MAX;
+ if (chan->scan_type.sign == 'u')
+ *val2 = PAC1934_VOLTAGE_U_RES;
+ else
+ *val2 = PAC1934_VOLTAGE_S_RES;
+ return IIO_VAL_FRACTIONAL_LOG2;
+ /*
+ * Currents - scale for mA - depends on the
+ * channel's shunt value
+ * (100mV * 1000000) / (2^16 * shunt(uohm))
+ */
+ case PAC1934_VSENSE_1_ADDR:
+ case PAC1934_VSENSE_2_ADDR:
+ case PAC1934_VSENSE_3_ADDR:
+ case PAC1934_VSENSE_4_ADDR:
+ case PAC1934_VSENSE_AVG_1_ADDR:
+ case PAC1934_VSENSE_AVG_2_ADDR:
+ case PAC1934_VSENSE_AVG_3_ADDR:
+ case PAC1934_VSENSE_AVG_4_ADDR:
+ *val = PAC1934_MAX_VSENSE_RSHIFTED_BY_16B;
+ if (chan->scan_type.sign == 'u')
+ *val2 = info->shunts[channel];
+ else
+ *val2 = info->shunts[channel] >> 1;
+ return IIO_VAL_FRACTIONAL;
+ /*
+ * Power - uW - it will use the combined scale
+ * for current and voltage
+ * current(mA) * voltage(mV) = power (uW)
+ */
+ case PAC1934_VPOWER_1_ADDR:
+ case PAC1934_VPOWER_2_ADDR:
+ case PAC1934_VPOWER_3_ADDR:
+ case PAC1934_VPOWER_4_ADDR:
+ *val = PAC1934_MAX_VPOWER_RSHIFTED_BY_28B;
+ if (chan->scan_type.sign == 'u')
+ *val2 = info->shunts[channel];
+ else
+ *val2 = info->shunts[channel] >> 1;
+ return IIO_VAL_FRACTIONAL;
+ case PAC1934_VPOWER_ACC_1_ADDR:
+ case PAC1934_VPOWER_ACC_2_ADDR:
+ case PAC1934_VPOWER_ACC_3_ADDR:
+ case PAC1934_VPOWER_ACC_4_ADDR:
+ /*
+ * expresses the 32 bit scale value here compute
+ * the scale for energy (miliWatt-second or miliJoule)
+ */
+ *val = PAC1934_SCALE_CONSTANT;
+
+ if (chan->scan_type.sign == 'u')
+ *val2 = info->shunts[channel];
+ else
+ *val2 = info->shunts[channel] >> 1;
+ return IIO_VAL_FRACTIONAL;
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ *val = info->sample_rate_value;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_ENABLE:
+ *val = info->enable_energy[channel];
+ return IIO_VAL_INT;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int pac1934_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct pac1934_chip_info *info = iio_priv(indio_dev);
+ struct i2c_client *client = info->client;
+ int ret = -EINVAL;
+ s32 old_samp_rate;
+ u8 ctrl_reg;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ ret = pac1934_get_samp_rate_idx(info, val);
+ if (ret < 0)
+ return ret;
+
+ /* write the new sampling value and trigger a snapshot(incl refresh) */
+ scoped_guard(mutex, &info->lock) {
+ ctrl_reg = FIELD_PREP(PAC1934_CRTL_SAMPLE_RATE_MASK, ret);
+ ret = i2c_smbus_write_byte_data(client, PAC1934_CTRL_REG_ADDR, ctrl_reg);
+ if (ret) {
+ dev_err(&client->dev,
+ "%s - can't update sample rate\n",
+ __func__);
+ return ret;
+ }
+ }
+
+ old_samp_rate = info->sample_rate_value;
+ info->sample_rate_value = val;
+
+ /*
+ * now, force a snapshot with refresh - call retrieve
+ * data in order to update the refresh timer
+ * alter the timestamp in order to force trigger a
+ * register snapshot and a timestamp update
+ */
+ info->tstamp -= msecs_to_jiffies(PAC1934_MIN_POLLING_TIME_MS);
+ ret = pac1934_retrieve_data(info, (1024 / old_samp_rate) * 1000);
+ if (ret < 0) {
+ dev_err(&client->dev,
+ "%s - cannot snapshot ctrl and measurement regs\n",
+ __func__);
+ return ret;
+ }
+
+ return 0;
+ case IIO_CHAN_INFO_ENABLE:
+ scoped_guard(mutex, &info->lock) {
+ info->enable_energy[chan->channel - 1] = val ? true : false;
+ if (!val)
+ info->chip_reg_data.energy_sec_acc[chan->channel - 1] = 0;
+ }
+
+ return 0;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int pac1934_read_label(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, char *label)
+{
+ struct pac1934_chip_info *info = iio_priv(indio_dev);
+
+ switch (chan->address) {
+ case PAC1934_VBUS_1_ADDR:
+ case PAC1934_VBUS_2_ADDR:
+ case PAC1934_VBUS_3_ADDR:
+ case PAC1934_VBUS_4_ADDR:
+ return sysfs_emit(label, "%s_VBUS_%d\n",
+ info->labels[chan->scan_index],
+ chan->scan_index + 1);
+ case PAC1934_VBUS_AVG_1_ADDR:
+ case PAC1934_VBUS_AVG_2_ADDR:
+ case PAC1934_VBUS_AVG_3_ADDR:
+ case PAC1934_VBUS_AVG_4_ADDR:
+ return sysfs_emit(label, "%s_VBUS_AVG_%d\n",
+ info->labels[chan->scan_index],
+ chan->scan_index + 1);
+ case PAC1934_VSENSE_1_ADDR:
+ case PAC1934_VSENSE_2_ADDR:
+ case PAC1934_VSENSE_3_ADDR:
+ case PAC1934_VSENSE_4_ADDR:
+ return sysfs_emit(label, "%s_IBUS_%d\n",
+ info->labels[chan->scan_index],
+ chan->scan_index + 1);
+ case PAC1934_VSENSE_AVG_1_ADDR:
+ case PAC1934_VSENSE_AVG_2_ADDR:
+ case PAC1934_VSENSE_AVG_3_ADDR:
+ case PAC1934_VSENSE_AVG_4_ADDR:
+ return sysfs_emit(label, "%s_IBUS_AVG_%d\n",
+ info->labels[chan->scan_index],
+ chan->scan_index + 1);
+ case PAC1934_VPOWER_1_ADDR:
+ case PAC1934_VPOWER_2_ADDR:
+ case PAC1934_VPOWER_3_ADDR:
+ case PAC1934_VPOWER_4_ADDR:
+ return sysfs_emit(label, "%s_POWER_%d\n",
+ info->labels[chan->scan_index],
+ chan->scan_index + 1);
+ case PAC1934_VPOWER_ACC_1_ADDR:
+ case PAC1934_VPOWER_ACC_2_ADDR:
+ case PAC1934_VPOWER_ACC_3_ADDR:
+ case PAC1934_VPOWER_ACC_4_ADDR:
+ return sysfs_emit(label, "%s_ENERGY_%d\n",
+ info->labels[chan->scan_index],
+ chan->scan_index + 1);
+ }
+
+ return 0;
+}
+
+static void pac1934_work_periodic_rfsh(struct work_struct *work)
+{
+ struct pac1934_chip_info *info = TO_PAC1934_CHIP_INFO((struct delayed_work *)work);
+ struct device *dev = &info->client->dev;
+
+ dev_dbg(dev, "%s - Periodic refresh\n", __func__);
+
+ /* do a REFRESH, then read */
+ pac1934_reg_snapshot(info, true, PAC1934_REFRESH_REG_ADDR,
+ PAC1934_MIN_UPDATE_WAIT_TIME_US);
+
+ schedule_delayed_work(&info->work_chip_rfsh,
+ msecs_to_jiffies(PAC1934_MAX_RFSH_LIMIT_MS));
+}
+
+static int pac1934_read_revision(struct pac1934_chip_info *info, u8 *buf)
+{
+ int ret;
+ struct i2c_client *client = info->client;
+
+ ret = i2c_smbus_read_i2c_block_data(client, PAC1934_PID_REG_ADDR,
+ PAC1934_ID_REG_LEN,
+ buf);
+ if (ret < 0) {
+ dev_err(&client->dev, "cannot read revision\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int pac1934_chip_identify(struct pac1934_chip_info *info)
+{
+ u8 rev_info[PAC1934_ID_REG_LEN];
+ struct device *dev = &info->client->dev;
+ int ret = 0;
+
+ ret = pac1934_read_revision(info, (u8 *)rev_info);
+ if (ret)
+ return ret;
+
+ info->chip_variant = rev_info[PAC1934_PID_IDX];
+ info->chip_revision = rev_info[PAC1934_RID_IDX];
+
+ dev_dbg(dev, "Chip variant: 0x%02X\n", info->chip_variant);
+ dev_dbg(dev, "Chip revision: 0x%02X\n", info->chip_revision);
+
+ switch (info->chip_variant) {
+ case PAC1934_PID:
+ return PAC1934;
+ case PAC1933_PID:
+ return PAC1933;
+ case PAC1932_PID:
+ return PAC1932;
+ case PAC1931_PID:
+ return PAC1931;
+ default:
+ return -EINVAL;
+ }
+}
+
+/*
+ * documentation related to the ACPI device definition
+ * https://ww1.microchip.com/downloads/aemDocuments/documents/OTH/ApplicationNotes/ApplicationNotes/PAC1934-Integration-Notes-for-Microsoft-Windows-10-and-Windows-11-Driver-Support-DS00002534.pdf
+ */
+static bool pac1934_acpi_parse_channel_config(struct i2c_client *client,
+ struct pac1934_chip_info *info)
+{
+ acpi_handle handle;
+ union acpi_object *rez;
+ struct device *dev = &client->dev;
+ unsigned short bi_dir_mask;
+ int idx, i;
+ guid_t guid;
+
+ handle = ACPI_HANDLE(dev);
+
+ guid_parse(PAC1934_DSM_UUID, &guid);
+
+ rez = acpi_evaluate_dsm(handle, &guid, 0, PAC1934_ACPI_GET_NAMES_AND_MOHMS_VALS, NULL);
+ if (!rez)
+ return false;
+
+ for (i = 0; i < rez->package.count; i += 2) {
+ idx = i / 2;
+ info->labels[idx] =
+ devm_kmemdup(dev, rez->package.elements[i].string.pointer,
+ (size_t)rez->package.elements[i].string.length + 1,
+ GFP_KERNEL);
+ info->labels[idx][rez->package.elements[i].string.length] = '\0';
+ info->shunts[idx] = rez->package.elements[i + 1].integer.value * 1000;
+ info->active_channels[idx] = (info->shunts[idx] != 0);
+ }
+
+ ACPI_FREE(rez);
+
+ rez = acpi_evaluate_dsm(handle, &guid, 1, PAC1934_ACPI_GET_UOHMS_VALS, NULL);
+ if (!rez) {
+ /*
+ * initializing with default values
+ * we assume all channels are unidirectional(the mask is zero)
+ * and assign the default sampling rate
+ */
+ info->sample_rate_value = PAC1934_DEFAULT_CHIP_SAMP_SPEED_HZ;
+ return true;
+ }
+
+ for (i = 0; i < rez->package.count; i++) {
+ idx = i;
+ info->shunts[idx] = rez->package.elements[i].integer.value;
+ info->active_channels[idx] = (info->shunts[idx] != 0);
+ }
+
+ ACPI_FREE(rez);
+
+ rez = acpi_evaluate_dsm(handle, &guid, 1, PAC1934_ACPI_GET_BIPOLAR_SETTINGS, NULL);
+ if (!rez)
+ return false;
+
+ bi_dir_mask = rez->package.elements[0].integer.value;
+ info->bi_dir[0] = ((bi_dir_mask & (1 << 3)) | (bi_dir_mask & (1 << 7))) != 0;
+ info->bi_dir[1] = ((bi_dir_mask & (1 << 2)) | (bi_dir_mask & (1 << 6))) != 0;
+ info->bi_dir[2] = ((bi_dir_mask & (1 << 1)) | (bi_dir_mask & (1 << 5))) != 0;
+ info->bi_dir[3] = ((bi_dir_mask & (1 << 0)) | (bi_dir_mask & (1 << 4))) != 0;
+
+ ACPI_FREE(rez);
+
+ rez = acpi_evaluate_dsm(handle, &guid, 1, PAC1934_ACPI_GET_SAMP, NULL);
+ if (!rez)
+ return false;
+
+ info->sample_rate_value = rez->package.elements[0].integer.value;
+
+ ACPI_FREE(rez);
+
+ return true;
+}
+
+static bool pac1934_of_parse_channel_config(struct i2c_client *client,
+ struct pac1934_chip_info *info)
+{
+ struct fwnode_handle *node, *fwnode;
+ struct device *dev = &client->dev;
+ unsigned int current_channel;
+ int idx, ret;
+
+ info->sample_rate_value = 1024;
+ current_channel = 1;
+
+ fwnode = dev_fwnode(dev);
+ fwnode_for_each_available_child_node(fwnode, node) {
+ ret = fwnode_property_read_u32(node, "reg", &idx);
+ if (ret) {
+ dev_err_probe(dev, ret,
+ "reading invalid channel index\n");
+ goto err_fwnode;
+ }
+ /* adjust idx to match channel index (1 to 4) from the datasheet */
+ idx--;
+
+ if (current_channel >= (info->phys_channels + 1) ||
+ idx >= info->phys_channels || idx < 0) {
+ dev_err_probe(dev, -EINVAL,
+ "%s: invalid channel_index %d value\n",
+ fwnode_get_name(node), idx);
+ goto err_fwnode;
+ }
+
+ /* enable channel */
+ info->active_channels[idx] = true;
+
+ ret = fwnode_property_read_u32(node, "shunt-resistor-micro-ohms",
+ &info->shunts[idx]);
+ if (ret) {
+ dev_err_probe(dev, ret,
+ "%s: invalid shunt-resistor value: %d\n",
+ fwnode_get_name(node), info->shunts[idx]);
+ goto err_fwnode;
+ }
+
+ if (fwnode_property_present(node, "label")) {
+ ret = fwnode_property_read_string(node, "label",
+ (const char **)&info->labels[idx]);
+ if (ret) {
+ dev_err_probe(dev, ret,
+ "%s: invalid rail-name value\n",
+ fwnode_get_name(node));
+ goto err_fwnode;
+ }
+ }
+
+ info->bi_dir[idx] = fwnode_property_read_bool(node, "bipolar");
+
+ current_channel++;
+ }
+
+ return true;
+
+err_fwnode:
+ fwnode_handle_put(node);
+
+ return false;
+}
+
+static void pac1934_cancel_delayed_work(void *dwork)
+{
+ cancel_delayed_work_sync(dwork);
+}
+
+static int pac1934_chip_configure(struct pac1934_chip_info *info)
+{
+ int cnt, ret;
+ struct i2c_client *client = info->client;
+ u8 regs[PAC1934_CTRL_STATUS_INFO_LEN], idx, ctrl_reg;
+ u32 wait_time;
+
+ info->chip_reg_data.num_enabled_channels = 0;
+ for (cnt = 0; cnt < info->phys_channels; cnt++) {
+ if (info->active_channels[cnt])
+ info->chip_reg_data.num_enabled_channels++;
+ }
+
+ /*
+ * read whatever information was gathered before the driver was loaded
+ * establish which channels are enabled/disabled and then establish the
+ * information retrieval mode (using SKIP or no).
+ * Read the chip ID values
+ */
+ ret = i2c_smbus_read_i2c_block_data(client, PAC1934_CTRL_STAT_REGS_ADDR,
+ ARRAY_SIZE(regs),
+ (u8 *)regs);
+ if (ret < 0) {
+ dev_err_probe(&client->dev, ret,
+ "%s - cannot read regs from 0x%02X\n",
+ __func__, PAC1934_CTRL_STAT_REGS_ADDR);
+ return ret;
+ }
+
+ /* write the CHANNEL_DIS and the NEG_PWR registers */
+ regs[PAC1934_CHANNEL_DIS_REG_OFF] =
+ FIELD_PREP(PAC1934_CHAN_DIS_CH1_OFF_MASK, info->active_channels[0] ? 0 : 1) |
+ FIELD_PREP(PAC1934_CHAN_DIS_CH2_OFF_MASK, info->active_channels[1] ? 0 : 1) |
+ FIELD_PREP(PAC1934_CHAN_DIS_CH3_OFF_MASK, info->active_channels[2] ? 0 : 1) |
+ FIELD_PREP(PAC1934_CHAN_DIS_CH4_OFF_MASK, info->active_channels[3] ? 0 : 1) |
+ FIELD_PREP(PAC1934_SMBUS_TIMEOUT_MASK, 0) |
+ FIELD_PREP(PAC1934_SMBUS_BYTECOUNT_MASK, 0) |
+ FIELD_PREP(PAC1934_SMBUS_NO_SKIP_MASK, 0);
+
+ regs[PAC1934_NEG_PWR_REG_OFF] =
+ FIELD_PREP(PAC1934_NEG_PWR_CH1_BIDI_MASK, info->bi_dir[0]) |
+ FIELD_PREP(PAC1934_NEG_PWR_CH2_BIDI_MASK, info->bi_dir[1]) |
+ FIELD_PREP(PAC1934_NEG_PWR_CH3_BIDI_MASK, info->bi_dir[2]) |
+ FIELD_PREP(PAC1934_NEG_PWR_CH4_BIDI_MASK, info->bi_dir[3]) |
+ FIELD_PREP(PAC1934_NEG_PWR_CH1_BIDV_MASK, info->bi_dir[0]) |
+ FIELD_PREP(PAC1934_NEG_PWR_CH2_BIDV_MASK, info->bi_dir[1]) |
+ FIELD_PREP(PAC1934_NEG_PWR_CH3_BIDV_MASK, info->bi_dir[2]) |
+ FIELD_PREP(PAC1934_NEG_PWR_CH4_BIDV_MASK, info->bi_dir[3]);
+
+ /* no SLOW triggered REFRESH, clear POR */
+ regs[PAC1934_SLOW_REG_OFF] = 0;
+
+ ret = i2c_smbus_write_block_data(client, PAC1934_CTRL_STAT_REGS_ADDR,
+ ARRAY_SIZE(regs), (u8 *)regs);
+ if (ret)
+ return ret;
+
+ /* Default sampling rate */
+ ctrl_reg = FIELD_PREP(PAC1934_CRTL_SAMPLE_RATE_MASK, PAC1934_SAMP_1024SPS);
+
+ ret = i2c_smbus_write_byte_data(client, PAC1934_CTRL_REG_ADDR, ctrl_reg);
+ if (ret)
+ return ret;
+
+ /*
+ * send a REFRESH to the chip, so the new settings take place
+ * as well as resetting the accumulators
+ */
+ ret = i2c_smbus_write_byte(client, PAC1934_REFRESH_REG_ADDR);
+ if (ret) {
+ dev_err(&client->dev,
+ "%s - cannot send 0x%02X\n",
+ __func__, PAC1934_REFRESH_REG_ADDR);
+ return ret;
+ }
+
+ /*
+ * get the current(in the chip) sampling speed and compute the
+ * required timeout based on its value
+ * the timeout is 1/sampling_speed
+ */
+ idx = regs[PAC1934_CTRL_ACT_REG_OFF] >> PAC1934_SAMPLE_RATE_SHIFT;
+ wait_time = (1024 / samp_rate_map_tbl[idx]) * 1000;
+
+ /*
+ * wait the maximum amount of time to be on the safe side
+ * the maximum wait time is for 8sps
+ */
+ usleep_range(wait_time, wait_time + 100);
+
+ INIT_DELAYED_WORK(&info->work_chip_rfsh, pac1934_work_periodic_rfsh);
+ /* Setup the latest moment for reading the regs before saturation */
+ schedule_delayed_work(&info->work_chip_rfsh,
+ msecs_to_jiffies(PAC1934_MAX_RFSH_LIMIT_MS));
+
+ return devm_add_action_or_reset(&client->dev, pac1934_cancel_delayed_work,
+ &info->work_chip_rfsh);
+}
+
+static int pac1934_prep_iio_channels(struct pac1934_chip_info *info, struct iio_dev *indio_dev)
+{
+ struct iio_chan_spec *ch_sp;
+ int channel_size, attribute_count, cnt;
+ void *dyn_ch_struct, *tmp_data;
+ struct device *dev = &info->client->dev;
+
+ /* find out dynamically how many IIO channels we need */
+ attribute_count = 0;
+ channel_size = 0;
+ for (cnt = 0; cnt < info->phys_channels; cnt++) {
+ if (!info->active_channels[cnt])
+ continue;
+
+ /* add the size of the properties of one chip physical channel */
+ channel_size += sizeof(pac1934_single_channel);
+ /* count how many enabled channels we have */
+ attribute_count += ARRAY_SIZE(pac1934_single_channel);
+ dev_dbg(dev, ":%s: Channel %d active\n", __func__, cnt + 1);
+ }
+
+ dyn_ch_struct = devm_kzalloc(dev, channel_size, GFP_KERNEL);
+ if (!dyn_ch_struct)
+ return -EINVAL;
+
+ tmp_data = dyn_ch_struct;
+
+ /* populate the dynamic channels and make all the adjustments */
+ for (cnt = 0; cnt < info->phys_channels; cnt++) {
+ if (!info->active_channels[cnt])
+ continue;
+
+ memcpy(tmp_data, pac1934_single_channel, sizeof(pac1934_single_channel));
+ ch_sp = (struct iio_chan_spec *)tmp_data;
+ ch_sp[PAC1934_CH_ENERGY].channel = cnt + 1;
+ ch_sp[PAC1934_CH_ENERGY].scan_index = cnt;
+ ch_sp[PAC1934_CH_ENERGY].address = cnt + PAC1934_VPOWER_ACC_1_ADDR;
+ ch_sp[PAC1934_CH_POWER].channel = cnt + 1;
+ ch_sp[PAC1934_CH_POWER].scan_index = cnt;
+ ch_sp[PAC1934_CH_POWER].address = cnt + PAC1934_VPOWER_1_ADDR;
+ ch_sp[PAC1934_CH_VOLTAGE].channel = cnt + 1;
+ ch_sp[PAC1934_CH_VOLTAGE].scan_index = cnt;
+ ch_sp[PAC1934_CH_VOLTAGE].address = cnt + PAC1934_VBUS_1_ADDR;
+ ch_sp[PAC1934_CH_CURRENT].channel = cnt + 1;
+ ch_sp[PAC1934_CH_CURRENT].scan_index = cnt;
+ ch_sp[PAC1934_CH_CURRENT].address = cnt + PAC1934_VSENSE_1_ADDR;
+
+ /*
+ * In order to be able to use labels for PAC1934_CH_VOLTAGE, and
+ * PAC1934_CH_VOLTAGE_AVERAGE,respectively PAC1934_CH_CURRENT
+ * and PAC1934_CH_CURRENT_AVERAGE we need to use different
+ * channel numbers. We will add +5 (+1 to maximum PAC channels).
+ */
+ ch_sp[PAC1934_CH_VOLTAGE_AVERAGE].channel = cnt + 5;
+ ch_sp[PAC1934_CH_VOLTAGE_AVERAGE].scan_index = cnt;
+ ch_sp[PAC1934_CH_VOLTAGE_AVERAGE].address = cnt + PAC1934_VBUS_AVG_1_ADDR;
+ ch_sp[PAC1934_CH_CURRENT_AVERAGE].channel = cnt + 5;
+ ch_sp[PAC1934_CH_CURRENT_AVERAGE].scan_index = cnt;
+ ch_sp[PAC1934_CH_CURRENT_AVERAGE].address = cnt + PAC1934_VSENSE_AVG_1_ADDR;
+
+ /*
+ * now modify the parameters in all channels if the
+ * whole chip rail(channel) is bi-directional
+ */
+ if (info->bi_dir[cnt]) {
+ ch_sp[PAC1934_CH_ENERGY].scan_type.sign = 's';
+ ch_sp[PAC1934_CH_ENERGY].scan_type.realbits = 47;
+ ch_sp[PAC1934_CH_POWER].scan_type.sign = 's';
+ ch_sp[PAC1934_CH_POWER].scan_type.realbits = 27;
+ ch_sp[PAC1934_CH_VOLTAGE].scan_type.sign = 's';
+ ch_sp[PAC1934_CH_VOLTAGE].scan_type.realbits = 15;
+ ch_sp[PAC1934_CH_CURRENT].scan_type.sign = 's';
+ ch_sp[PAC1934_CH_CURRENT].scan_type.realbits = 15;
+ ch_sp[PAC1934_CH_VOLTAGE_AVERAGE].scan_type.sign = 's';
+ ch_sp[PAC1934_CH_VOLTAGE_AVERAGE].scan_type.realbits = 15;
+ ch_sp[PAC1934_CH_CURRENT_AVERAGE].scan_type.sign = 's';
+ ch_sp[PAC1934_CH_CURRENT_AVERAGE].scan_type.realbits = 15;
+ }
+ tmp_data += sizeof(pac1934_single_channel);
+ }
+
+ /*
+ * send the updated dynamic channel structure information towards IIO
+ * prepare the required field for IIO class registration
+ */
+ indio_dev->num_channels = attribute_count;
+ indio_dev->channels = (const struct iio_chan_spec *)dyn_ch_struct;
+
+ return 0;
+}
+
+static IIO_DEVICE_ATTR(in_shunt_resistor1, 0644,
+ pac1934_shunt_value_show, pac1934_shunt_value_store, 0);
+static IIO_DEVICE_ATTR(in_shunt_resistor2, 0644,
+ pac1934_shunt_value_show, pac1934_shunt_value_store, 1);
+static IIO_DEVICE_ATTR(in_shunt_resistor3, 0644,
+ pac1934_shunt_value_show, pac1934_shunt_value_store, 2);
+static IIO_DEVICE_ATTR(in_shunt_resistor4, 0644,
+ pac1934_shunt_value_show, pac1934_shunt_value_store, 3);
+
+static int pac1934_prep_custom_attributes(struct pac1934_chip_info *info,
+ struct iio_dev *indio_dev)
+{
+ int i, active_channels_count = 0;
+ struct attribute **pac1934_custom_attr;
+ struct attribute_group *pac1934_group;
+ struct device *dev = &info->client->dev;
+
+ for (i = 0 ; i < info->phys_channels; i++)
+ if (info->active_channels[i])
+ active_channels_count++;
+
+ pac1934_group = devm_kzalloc(dev, sizeof(*pac1934_group), GFP_KERNEL);
+ if (!pac1934_group)
+ return -ENOMEM;
+
+ pac1934_custom_attr = devm_kzalloc(dev,
+ (PAC1934_CUSTOM_ATTR_FOR_CHANNEL *
+ active_channels_count)
+ * sizeof(*pac1934_group) + 1,
+ GFP_KERNEL);
+ if (!pac1934_custom_attr)
+ return -ENOMEM;
+
+ i = 0;
+ if (info->active_channels[0])
+ pac1934_custom_attr[i++] = PAC1934_DEV_ATTR(in_shunt_resistor1);
+
+ if (info->active_channels[1])
+ pac1934_custom_attr[i++] = PAC1934_DEV_ATTR(in_shunt_resistor2);
+
+ if (info->active_channels[2])
+ pac1934_custom_attr[i++] = PAC1934_DEV_ATTR(in_shunt_resistor3);
+
+ if (info->active_channels[3])
+ pac1934_custom_attr[i] = PAC1934_DEV_ATTR(in_shunt_resistor4);
+
+ pac1934_group->attrs = pac1934_custom_attr;
+ info->iio_info.attrs = pac1934_group;
+
+ return 0;
+}
+
+static void pac1934_mutex_destroy(void *data)
+{
+ struct mutex *lock = data;
+
+ mutex_destroy(lock);
+}
+
+static const struct iio_info pac1934_info = {
+ .read_raw = pac1934_read_raw,
+ .write_raw = pac1934_write_raw,
+ .read_avail = pac1934_read_avail,
+ .read_label = pac1934_read_label,
+};
+
+static int pac1934_probe(struct i2c_client *client)
+{
+ struct pac1934_chip_info *info;
+ const struct pac1934_features *chip;
+ struct iio_dev *indio_dev;
+ int cnt, ret;
+ bool match = false;
+ struct device *dev = &client->dev;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*info));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ info = iio_priv(indio_dev);
+
+ info->client = client;
+
+ /* always start with energy accumulation enabled */
+ for (cnt = 0; cnt < PAC1934_MAX_NUM_CHANNELS; cnt++)
+ info->enable_energy[cnt] = true;
+
+ ret = pac1934_chip_identify(info);
+ if (ret < 0) {
+ /*
+ * If failed to identify the hardware based on internal
+ * registers, try using fallback compatible in device tree
+ * to deal with some newer part number.
+ */
+ chip = i2c_get_match_data(client);
+ if (!chip)
+ return -EINVAL;
+
+ info->phys_channels = chip->phys_channels;
+ indio_dev->name = chip->name;
+ } else {
+ info->phys_channels = pac1934_chip_config[ret].phys_channels;
+ indio_dev->name = pac1934_chip_config[ret].name;
+ }
+
+ if (acpi_match_device(dev->driver->acpi_match_table, dev))
+ match = pac1934_acpi_parse_channel_config(client, info);
+ else
+ /*
+ * This makes it possible to use also ACPI PRP0001 for
+ * registering the device using device tree properties.
+ */
+ match = pac1934_of_parse_channel_config(client, info);
+
+ if (!match)
+ return dev_err_probe(dev, -EINVAL,
+ "parameter parsing returned an error\n");
+
+ mutex_init(&info->lock);
+ ret = devm_add_action_or_reset(dev, pac1934_mutex_destroy,
+ &info->lock);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * do now any chip specific initialization (e.g. read/write
+ * some registers), enable/disable certain channels, change the sampling
+ * rate to the requested value
+ */
+ ret = pac1934_chip_configure(info);
+ if (ret < 0)
+ return ret;
+
+ /* prepare the channel information */
+ ret = pac1934_prep_iio_channels(info, indio_dev);
+ if (ret < 0)
+ return ret;
+
+ info->iio_info = pac1934_info;
+ indio_dev->info = &info->iio_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ ret = pac1934_prep_custom_attributes(info, indio_dev);
+ if (ret < 0)
+ return dev_err_probe(dev, ret,
+ "Can't configure custom attributes for PAC1934 device\n");
+
+ /*
+ * read whatever has been accumulated in the chip so far
+ * and reset the accumulators
+ */
+ ret = pac1934_reg_snapshot(info, true, PAC1934_REFRESH_REG_ADDR,
+ PAC1934_MIN_UPDATE_WAIT_TIME_US);
+ if (ret < 0)
+ return ret;
+
+ ret = devm_iio_device_register(dev, indio_dev);
+ if (ret < 0)
+ return dev_err_probe(dev, ret,
+ "Can't register IIO device\n");
+
+ return 0;
+}
+
+static const struct i2c_device_id pac1934_id[] = {
+ { .name = "pac1931", .driver_data = (kernel_ulong_t)&pac1934_chip_config[PAC1931] },
+ { .name = "pac1932", .driver_data = (kernel_ulong_t)&pac1934_chip_config[PAC1932] },
+ { .name = "pac1933", .driver_data = (kernel_ulong_t)&pac1934_chip_config[PAC1933] },
+ { .name = "pac1934", .driver_data = (kernel_ulong_t)&pac1934_chip_config[PAC1934] },
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, pac1934_id);
+
+static const struct of_device_id pac1934_of_match[] = {
+ {
+ .compatible = "microchip,pac1931",
+ .data = &pac1934_chip_config[PAC1931]
+ },
+ {
+ .compatible = "microchip,pac1932",
+ .data = &pac1934_chip_config[PAC1932]
+ },
+ {
+ .compatible = "microchip,pac1933",
+ .data = &pac1934_chip_config[PAC1933]
+ },
+ {
+ .compatible = "microchip,pac1934",
+ .data = &pac1934_chip_config[PAC1934]
+ },
+ {}
+};
+MODULE_DEVICE_TABLE(of, pac1934_of_match);
+
+/*
+ * using MCHP1930 to be compatible with BIOS ACPI. See example:
+ * https://ww1.microchip.com/downloads/aemDocuments/documents/OTH/ApplicationNotes/ApplicationNotes/PAC1934-Integration-Notes-for-Microsoft-Windows-10-and-Windows-11-Driver-Support-DS00002534.pdf
+ */
+static const struct acpi_device_id pac1934_acpi_match[] = {
+ { "MCHP1930", .driver_data = (kernel_ulong_t)&pac1934_chip_config[PAC1934] },
+ {}
+};
+MODULE_DEVICE_TABLE(acpi, pac1934_acpi_match);
+
+static struct i2c_driver pac1934_driver = {
+ .driver = {
+ .name = "pac1934",
+ .of_match_table = pac1934_of_match,
+ .acpi_match_table = pac1934_acpi_match
+ },
+ .probe = pac1934_probe,
+ .id_table = pac1934_id,
+};
+
+module_i2c_driver(pac1934_driver);
+
+MODULE_AUTHOR("Bogdan Bolocan <bogdan.bolocan@microchip.com>");
+MODULE_AUTHOR("Victor Tudose");
+MODULE_AUTHOR("Marius Cristea <marius.cristea@microchip.com>");
+MODULE_DESCRIPTION("IIO driver for PAC1934 Multi-Channel DC Power/Energy Monitor");
+MODULE_LICENSE("GPL");