// SPDX-License-Identifier: GPL-2.0+ /* * IIO driver for MCP47FEB02 Multi-Channel DAC with I2C interface * * Copyright (C) 2025 Microchip Technology Inc. and its subsidiaries * * Author: Ariana Lazar * * Datasheet links: * [MCP47FEBxx] https://ww1.microchip.com/downloads/aemDocuments/documents/OTH/ProductDocuments/DataSheets/20005375A.pdf * [MCP47FVBxx] https://ww1.microchip.com/downloads/aemDocuments/documents/OTH/ProductDocuments/DataSheets/20005405A.pdf * [MCP47FxBx4/8] https://ww1.microchip.com/downloads/aemDocuments/documents/MSLD/ProductDocuments/DataSheets/MCP47FXBX48-Data-Sheet-DS200006368A.pdf */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* Register addresses must be left shifted with 3 positions in order to append command mask */ #define MCP47FEB02_DAC0_REG_ADDR 0x00 #define MCP47FEB02_VREF_REG_ADDR 0x40 #define MCP47FEB02_POWER_DOWN_REG_ADDR 0x48 #define MCP47FEB02_DAC_CTRL_MASK GENMASK(1, 0) #define MCP47FEB02_GAIN_CTRL_STATUS_REG_ADDR 0x50 #define MCP47FEB02_GAIN_BIT_MASK BIT(0) #define MCP47FEB02_GAIN_BIT_STATUS_EEWA_MASK BIT(6) #define MCP47FEB02_GAIN_BITS_MASK GENMASK(15, 8) #define MCP47FEB02_WIPERLOCK_STATUS_REG_ADDR 0x58 #define MCP47FEB02_NV_DAC0_REG_ADDR 0x80 #define MCP47FEB02_NV_VREF_REG_ADDR 0xC0 #define MCP47FEB02_NV_POWER_DOWN_REG_ADDR 0xC8 #define MCP47FEB02_NV_GAIN_CTRL_I2C_SLAVE_REG_ADDR 0xD0 #define MCP47FEB02_NV_I2C_SLAVE_ADDR_MASK GENMASK(7, 0) /* Voltage reference, Power-Down control register and DAC Wiperlock status register fields */ #define DAC_CTRL_MASK(ch) (GENMASK(1, 0) << (2 * (ch))) #define DAC_CTRL_VAL(ch, val) ((val) << (2 * (ch))) /* Gain Control and I2C Slave Address Reguster fields */ #define DAC_GAIN_MASK(ch) (BIT(0) << (8 + (ch))) #define DAC_GAIN_VAL(ch, val) ((val) << (8 + (ch))) #define REG_ADDR(reg) ((reg) << 3) #define NV_REG_ADDR(reg) ((NV_DAC_ADDR_OFFSET + (reg)) << 3) #define READFLAG_MASK GENMASK(2, 1) #define MCP47FEB02_MAX_CH 8 #define MCP47FEB02_MAX_SCALES_CH 3 #define MCP47FEB02_DAC_WIPER_UNLOCKED 0 #define MCP47FEB02_NORMAL_OPERATION 0 #define MCP47FEB02_INTERNAL_BAND_GAP_mV 2440 #define NV_DAC_ADDR_OFFSET 0x10 enum mcp47feb02_vref_mode { MCP47FEB02_VREF_VDD = 0, MCP47FEB02_INTERNAL_BAND_GAP = 1, MCP47FEB02_EXTERNAL_VREF_UNBUFFERED = 2, MCP47FEB02_EXTERNAL_VREF_BUFFERED = 3, }; enum mcp47feb02_scale { MCP47FEB02_SCALE_VDD = 0, MCP47FEB02_SCALE_GAIN_X1 = 1, MCP47FEB02_SCALE_GAIN_X2 = 2, }; enum mcp47feb02_gain_bit_mode { MCP47FEB02_GAIN_BIT_X1 = 0, MCP47FEB02_GAIN_BIT_X2 = 1, }; static const char * const mcp47feb02_powerdown_modes[] = { "1kohm_to_gnd", "100kohm_to_gnd", "open_circuit", }; /** * struct mcp47feb02_features - chip specific data * @name: device name * @phys_channels: number of hardware channels * @resolution: DAC resolution * @have_ext_vref1: does the hardware have an the second external voltage reference? * @have_eeprom: does the hardware have an internal eeprom? */ struct mcp47feb02_features { const char *name; unsigned int phys_channels; unsigned int resolution; bool have_ext_vref1; bool have_eeprom; }; static const struct mcp47feb02_features mcp47feb01_chip_features = { .name = "mcp47feb01", .phys_channels = 1, .resolution = 8, .have_ext_vref1 = false, .have_eeprom = true, }; static const struct mcp47feb02_features mcp47feb02_chip_features = { .name = "mcp47feb02", .phys_channels = 2, .resolution = 8, .have_ext_vref1 = false, .have_eeprom = true, }; static const struct mcp47feb02_features mcp47feb04_chip_features = { .name = "mcp47feb04", .phys_channels = 4, .resolution = 8, .have_ext_vref1 = true, .have_eeprom = true, }; static const struct mcp47feb02_features mcp47feb08_chip_features = { .name = "mcp47feb08", .phys_channels = 8, .resolution = 8, .have_ext_vref1 = true, .have_eeprom = true, }; static const struct mcp47feb02_features mcp47feb11_chip_features = { .name = "mcp47feb11", .phys_channels = 1, .resolution = 10, .have_ext_vref1 = false, .have_eeprom = true, }; static const struct mcp47feb02_features mcp47feb12_chip_features = { .name = "mcp47feb12", .phys_channels = 2, .resolution = 10, .have_ext_vref1 = false, .have_eeprom = true, }; static const struct mcp47feb02_features mcp47feb14_chip_features = { .name = "mcp47feb14", .phys_channels = 4, .resolution = 10, .have_ext_vref1 = true, .have_eeprom = true, }; static const struct mcp47feb02_features mcp47feb18_chip_features = { .name = "mcp47feb18", .phys_channels = 8, .resolution = 10, .have_ext_vref1 = true, .have_eeprom = true, }; static const struct mcp47feb02_features mcp47feb21_chip_features = { .name = "mcp47feb21", .phys_channels = 1, .resolution = 12, .have_ext_vref1 = false, .have_eeprom = true, }; static const struct mcp47feb02_features mcp47feb22_chip_features = { .name = "mcp47feb22", .phys_channels = 2, .resolution = 12, .have_ext_vref1 = false, .have_eeprom = true, }; static const struct mcp47feb02_features mcp47feb24_chip_features = { .name = "mcp47feb24", .phys_channels = 4, .resolution = 12, .have_ext_vref1 = true, .have_eeprom = true, }; static const struct mcp47feb02_features mcp47feb28_chip_features = { .name = "mcp47feb28", .phys_channels = 8, .resolution = 12, .have_ext_vref1 = true, .have_eeprom = true, }; static const struct mcp47feb02_features mcp47fvb01_chip_features = { .name = "mcp47fvb01", .phys_channels = 1, .resolution = 8, .have_ext_vref1 = false, .have_eeprom = false, }; static const struct mcp47feb02_features mcp47fvb02_chip_features = { .name = "mcp47fvb02", .phys_channels = 2, .resolution = 8, .have_ext_vref1 = false, .have_eeprom = false, }; static const struct mcp47feb02_features mcp47fvb04_chip_features = { .name = "mcp47fvb04", .phys_channels = 4, .resolution = 8, .have_ext_vref1 = true, .have_eeprom = false, }; static const struct mcp47feb02_features mcp47fvb08_chip_features = { .name = "mcp47fvb08", .phys_channels = 8, .resolution = 8, .have_ext_vref1 = true, .have_eeprom = false, }; static const struct mcp47feb02_features mcp47fvb11_chip_features = { .name = "mcp47fvb11", .phys_channels = 1, .resolution = 10, .have_ext_vref1 = false, .have_eeprom = false, }; static const struct mcp47feb02_features mcp47fvb12_chip_features = { .name = "mcp47fvb12", .phys_channels = 2, .resolution = 10, .have_ext_vref1 = false, .have_eeprom = false, }; static const struct mcp47feb02_features mcp47fvb14_chip_features = { .name = "mcp47fvb14", .phys_channels = 4, .resolution = 10, .have_ext_vref1 = true, .have_eeprom = false, }; static const struct mcp47feb02_features mcp47fvb18_chip_features = { .name = "mcp47fvb18", .phys_channels = 8, .resolution = 10, .have_ext_vref1 = true, .have_eeprom = false, }; static const struct mcp47feb02_features mcp47fvb21_chip_features = { .name = "mcp47fvb21", .phys_channels = 1, .resolution = 12, .have_ext_vref1 = false, .have_eeprom = false, }; static const struct mcp47feb02_features mcp47fvb22_chip_features = { .name = "mcp47fvb22", .phys_channels = 2, .resolution = 12, .have_ext_vref1 = false, .have_eeprom = false, }; static const struct mcp47feb02_features mcp47fvb24_chip_features = { .name = "mcp47fvb24", .phys_channels = 4, .resolution = 12, .have_ext_vref1 = true, .have_eeprom = false, }; static const struct mcp47feb02_features mcp47fvb28_chip_features = { .name = "mcp47fvb28", .phys_channels = 8, .resolution = 12, .have_ext_vref1 = true, .have_eeprom = false, }; /** * struct mcp47feb02_channel_data - channel configuration * @ref_mode: chosen voltage for reference * @use_2x_gain: output driver gain control * @powerdown: is false if the channel is in normal operation mode * @powerdown_mode: selected power-down mode * @dac_data: dac value */ struct mcp47feb02_channel_data { u8 ref_mode; bool use_2x_gain; bool powerdown; u8 powerdown_mode; u16 dac_data; }; /** * struct mcp47feb02_data - chip configuration * @chdata: options configured for each channel on the device * @lock: prevents concurrent reads/writes to driver's state members * @chip_features: pointer to features struct * @scale_1: scales set on channels that are based on Vref1 * @scale: scales set on channels that are based on Vref/Vref0 * @active_channels_mask: enabled channels * @regmap: regmap for directly accessing device register * @labels: table with channels labels * @phys_channels: physical channels on the device * @vref1_buffered: Vref1 buffer is enabled * @vref_buffered: Vref/Vref0 buffer is enabled * @use_vref1: vref1-supply is defined * @use_vref: vref-supply is defined */ struct mcp47feb02_data { struct mcp47feb02_channel_data chdata[MCP47FEB02_MAX_CH]; struct mutex lock; /* prevents concurrent reads/writes to driver's state members */ const struct mcp47feb02_features *chip_features; int scale_1[2 * MCP47FEB02_MAX_SCALES_CH]; int scale[2 * MCP47FEB02_MAX_SCALES_CH]; unsigned long active_channels_mask; struct regmap *regmap; const char *labels[MCP47FEB02_MAX_CH]; u16 phys_channels; bool vref1_buffered; bool vref_buffered; bool use_vref1; bool use_vref; }; static const struct regmap_range mcp47feb02_readable_ranges[] = { regmap_reg_range(MCP47FEB02_DAC0_REG_ADDR, MCP47FEB02_WIPERLOCK_STATUS_REG_ADDR), regmap_reg_range(MCP47FEB02_NV_DAC0_REG_ADDR, MCP47FEB02_NV_GAIN_CTRL_I2C_SLAVE_REG_ADDR), }; static const struct regmap_range mcp47feb02_writable_ranges[] = { regmap_reg_range(MCP47FEB02_DAC0_REG_ADDR, MCP47FEB02_WIPERLOCK_STATUS_REG_ADDR), regmap_reg_range(MCP47FEB02_NV_DAC0_REG_ADDR, MCP47FEB02_NV_GAIN_CTRL_I2C_SLAVE_REG_ADDR), }; static const struct regmap_range mcp47feb02_volatile_ranges[] = { regmap_reg_range(MCP47FEB02_DAC0_REG_ADDR, MCP47FEB02_WIPERLOCK_STATUS_REG_ADDR), regmap_reg_range(MCP47FEB02_NV_DAC0_REG_ADDR, MCP47FEB02_NV_GAIN_CTRL_I2C_SLAVE_REG_ADDR), regmap_reg_range(MCP47FEB02_DAC0_REG_ADDR, MCP47FEB02_WIPERLOCK_STATUS_REG_ADDR), regmap_reg_range(MCP47FEB02_NV_DAC0_REG_ADDR, MCP47FEB02_NV_GAIN_CTRL_I2C_SLAVE_REG_ADDR), }; static const struct regmap_access_table mcp47feb02_readable_table = { .yes_ranges = mcp47feb02_readable_ranges, .n_yes_ranges = ARRAY_SIZE(mcp47feb02_readable_ranges), }; static const struct regmap_access_table mcp47feb02_writable_table = { .yes_ranges = mcp47feb02_writable_ranges, .n_yes_ranges = ARRAY_SIZE(mcp47feb02_writable_ranges), }; static const struct regmap_access_table mcp47feb02_volatile_table = { .yes_ranges = mcp47feb02_volatile_ranges, .n_yes_ranges = ARRAY_SIZE(mcp47feb02_volatile_ranges), }; static const struct regmap_config mcp47feb02_regmap_config = { .name = "mcp47feb02_regmap", .reg_bits = 8, .val_bits = 16, .rd_table = &mcp47feb02_readable_table, .wr_table = &mcp47feb02_writable_table, .volatile_table = &mcp47feb02_volatile_table, .max_register = MCP47FEB02_NV_GAIN_CTRL_I2C_SLAVE_REG_ADDR, .read_flag_mask = READFLAG_MASK, .cache_type = REGCACHE_MAPLE, .val_format_endian = REGMAP_ENDIAN_BIG, }; /* For devices that doesn't have nonvolatile memory */ static const struct regmap_range mcp47fvb02_readable_ranges[] = { regmap_reg_range(MCP47FEB02_DAC0_REG_ADDR, MCP47FEB02_WIPERLOCK_STATUS_REG_ADDR), }; static const struct regmap_range mcp47fvb02_writable_ranges[] = { regmap_reg_range(MCP47FEB02_DAC0_REG_ADDR, MCP47FEB02_WIPERLOCK_STATUS_REG_ADDR), }; static const struct regmap_range mcp47fvb02_volatile_ranges[] = { regmap_reg_range(MCP47FEB02_DAC0_REG_ADDR, MCP47FEB02_WIPERLOCK_STATUS_REG_ADDR), regmap_reg_range(MCP47FEB02_DAC0_REG_ADDR, MCP47FEB02_WIPERLOCK_STATUS_REG_ADDR), }; static const struct regmap_access_table mcp47fvb02_readable_table = { .yes_ranges = mcp47fvb02_readable_ranges, .n_yes_ranges = ARRAY_SIZE(mcp47fvb02_readable_ranges), }; static const struct regmap_access_table mcp47fvb02_writable_table = { .yes_ranges = mcp47fvb02_writable_ranges, .n_yes_ranges = ARRAY_SIZE(mcp47fvb02_writable_ranges), }; static const struct regmap_access_table mcp47fvb02_volatile_table = { .yes_ranges = mcp47fvb02_volatile_ranges, .n_yes_ranges = ARRAY_SIZE(mcp47fvb02_volatile_ranges), }; static const struct regmap_config mcp47fvb02_regmap_config = { .name = "mcp47fvb02_regmap", .reg_bits = 8, .val_bits = 16, .rd_table = &mcp47fvb02_readable_table, .wr_table = &mcp47fvb02_writable_table, .volatile_table = &mcp47fvb02_volatile_table, .max_register = MCP47FEB02_WIPERLOCK_STATUS_REG_ADDR, .read_flag_mask = READFLAG_MASK, .cache_type = REGCACHE_MAPLE, .val_format_endian = REGMAP_ENDIAN_BIG, }; static int mcp47feb02_write_to_eeprom(struct mcp47feb02_data *data, unsigned int reg, unsigned int val) { int eewa_val, ret; /* * Wait until the currently occurring EEPROM Write Cycle is completed. * Only serial commands to the volatile memory are allowed. */ guard(mutex)(&data->lock); ret = regmap_read_poll_timeout(data->regmap, MCP47FEB02_GAIN_CTRL_STATUS_REG_ADDR, eewa_val, !(eewa_val & MCP47FEB02_GAIN_BIT_STATUS_EEWA_MASK), USEC_PER_MSEC, USEC_PER_MSEC * 5); if (ret) return ret; return regmap_write(data->regmap, reg, val); } static ssize_t store_eeprom_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { struct mcp47feb02_data *data = iio_priv(dev_to_iio_dev(dev)); unsigned int i, val, val1, eewa_val; bool state; int ret; ret = kstrtobool(buf, &state); if (ret) return ret; if (!state) return 0; /* * Verify DAC Wiper and DAC Configuration are unlocked. If both are disabled, * writing to EEPROM is available. */ ret = regmap_read(data->regmap, MCP47FEB02_WIPERLOCK_STATUS_REG_ADDR, &val); if (ret) return ret; if (val) { dev_err(dev, "DAC Wiper and DAC Configuration not are unlocked.\n"); return -EINVAL; } for_each_set_bit(i, &data->active_channels_mask, data->phys_channels) { ret = mcp47feb02_write_to_eeprom(data, NV_REG_ADDR(i), data->chdata[i].dac_data); if (ret) return ret; } ret = regmap_read(data->regmap, MCP47FEB02_VREF_REG_ADDR, &val); if (ret) return ret; ret = mcp47feb02_write_to_eeprom(data, MCP47FEB02_NV_VREF_REG_ADDR, val); if (ret) return ret; ret = regmap_read(data->regmap, MCP47FEB02_POWER_DOWN_REG_ADDR, &val); if (ret) return ret; ret = mcp47feb02_write_to_eeprom(data, MCP47FEB02_NV_POWER_DOWN_REG_ADDR, val); if (ret) return ret; ret = regmap_read_poll_timeout(data->regmap, MCP47FEB02_GAIN_CTRL_STATUS_REG_ADDR, eewa_val, !(eewa_val & MCP47FEB02_GAIN_BIT_STATUS_EEWA_MASK), USEC_PER_MSEC, USEC_PER_MSEC * 5); if (ret) return ret; ret = regmap_read(data->regmap, MCP47FEB02_NV_GAIN_CTRL_I2C_SLAVE_REG_ADDR, &val); if (ret) return ret; ret = regmap_read(data->regmap, MCP47FEB02_GAIN_CTRL_STATUS_REG_ADDR, &val1); if (ret) return ret; ret = mcp47feb02_write_to_eeprom(data, MCP47FEB02_NV_GAIN_CTRL_I2C_SLAVE_REG_ADDR, (val1 & MCP47FEB02_GAIN_BITS_MASK) | (val & MCP47FEB02_NV_I2C_SLAVE_ADDR_MASK)); if (ret) return ret; return len; } static IIO_DEVICE_ATTR_WO(store_eeprom, 0); static struct attribute *mcp47feb02_attributes[] = { &iio_dev_attr_store_eeprom.dev_attr.attr, NULL }; static const struct attribute_group mcp47feb02_attribute_group = { .attrs = mcp47feb02_attributes, }; static int mcp47feb02_suspend(struct device *dev) { struct iio_dev *indio_dev = dev_get_drvdata(dev); struct mcp47feb02_data *data = iio_priv(indio_dev); int ret; u8 ch; guard(mutex)(&data->lock); for_each_set_bit(ch, &data->active_channels_mask, data->phys_channels) { u8 pd_mode; data->chdata[ch].powerdown = true; pd_mode = data->chdata[ch].powerdown_mode + 1; ret = regmap_update_bits(data->regmap, MCP47FEB02_POWER_DOWN_REG_ADDR, DAC_CTRL_MASK(ch), DAC_CTRL_VAL(ch, pd_mode)); if (ret) return ret; ret = regmap_write(data->regmap, REG_ADDR(ch), data->chdata[ch].dac_data); if (ret) return ret; } return 0; } static int mcp47feb02_resume(struct device *dev) { struct iio_dev *indio_dev = dev_get_drvdata(dev); struct mcp47feb02_data *data = iio_priv(indio_dev); u8 ch; guard(mutex)(&data->lock); for_each_set_bit(ch, &data->active_channels_mask, data->phys_channels) { u8 pd_mode; int ret; data->chdata[ch].powerdown = false; pd_mode = data->chdata[ch].powerdown_mode + 1; ret = regmap_write(data->regmap, REG_ADDR(ch), data->chdata[ch].dac_data); if (ret) return ret; ret = regmap_update_bits(data->regmap, MCP47FEB02_VREF_REG_ADDR, DAC_CTRL_MASK(ch), DAC_CTRL_VAL(ch, pd_mode)); if (ret) return ret; ret = regmap_update_bits(data->regmap, MCP47FEB02_GAIN_CTRL_STATUS_REG_ADDR, DAC_GAIN_MASK(ch), DAC_GAIN_VAL(ch, data->chdata[ch].use_2x_gain)); if (ret) return ret; ret = regmap_update_bits(data->regmap, MCP47FEB02_POWER_DOWN_REG_ADDR, DAC_CTRL_MASK(ch), DAC_CTRL_VAL(ch, MCP47FEB02_NORMAL_OPERATION)); if (ret) return ret; } return 0; } static int mcp47feb02_get_powerdown_mode(struct iio_dev *indio_dev, const struct iio_chan_spec *chan) { struct mcp47feb02_data *data = iio_priv(indio_dev); return data->chdata[chan->address].powerdown_mode; } static int mcp47feb02_set_powerdown_mode(struct iio_dev *indio_dev, const struct iio_chan_spec *ch, unsigned int mode) { struct mcp47feb02_data *data = iio_priv(indio_dev); data->chdata[ch->address].powerdown_mode = mode; return 0; } static ssize_t mcp47feb02_read_powerdown(struct iio_dev *indio_dev, uintptr_t private, const struct iio_chan_spec *ch, char *buf) { struct mcp47feb02_data *data = iio_priv(indio_dev); /* Print if channel is in a power-down mode or not */ return sysfs_emit(buf, "%d\n", data->chdata[ch->address].powerdown); } static ssize_t mcp47feb02_write_powerdown(struct iio_dev *indio_dev, uintptr_t private, const struct iio_chan_spec *ch, const char *buf, size_t len) { struct mcp47feb02_data *data = iio_priv(indio_dev); u32 reg = ch->address; u8 tmp_pd_mode; bool state; int ret; guard(mutex)(&data->lock); ret = kstrtobool(buf, &state); if (ret) return ret; /* * Set the channel to the specified power-down mode. Exiting power-down mode * requires writing normal operation mode (0) to the channel-specific register bits. */ tmp_pd_mode = state ? (data->chdata[reg].powerdown_mode + 1) : MCP47FEB02_NORMAL_OPERATION; ret = regmap_update_bits(data->regmap, MCP47FEB02_POWER_DOWN_REG_ADDR, DAC_CTRL_MASK(reg), DAC_CTRL_VAL(reg, tmp_pd_mode)); if (ret) return ret; data->chdata[reg].powerdown = state; return len; } static DEFINE_SIMPLE_DEV_PM_OPS(mcp47feb02_pm_ops, mcp47feb02_suspend, mcp47feb02_resume); static const struct iio_enum mcp47febxx_powerdown_mode_enum = { .items = mcp47feb02_powerdown_modes, .num_items = ARRAY_SIZE(mcp47feb02_powerdown_modes), .get = mcp47feb02_get_powerdown_mode, .set = mcp47feb02_set_powerdown_mode, }; static const struct iio_chan_spec_ext_info mcp47feb02_ext_info[] = { { .name = "powerdown", .read = mcp47feb02_read_powerdown, .write = mcp47feb02_write_powerdown, .shared = IIO_SEPARATE, }, IIO_ENUM("powerdown_mode", IIO_SEPARATE, &mcp47febxx_powerdown_mode_enum), IIO_ENUM_AVAILABLE("powerdown_mode", IIO_SHARED_BY_TYPE, &mcp47febxx_powerdown_mode_enum), { } }; static const struct iio_chan_spec mcp47febxx_ch_template = { .type = IIO_VOLTAGE, .output = 1, .indexed = 1, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), .info_mask_separate_available = BIT(IIO_CHAN_INFO_SCALE), .ext_info = mcp47feb02_ext_info, }; static void mcp47feb02_init_scale(struct mcp47feb02_data *data, enum mcp47feb02_scale scale, int vref_mV, int scale_avail[]) { u32 value_micro, value_int; u64 tmp; /* vref_mV should not be negative */ tmp = (u64)vref_mV * MICRO >> data->chip_features->resolution; value_int = div_u64_rem(tmp, MICRO, &value_micro); scale_avail[scale * 2] = value_int; scale_avail[scale * 2 + 1] = value_micro; } static int mcp47feb02_init_scales_avail(struct mcp47feb02_data *data, int vdd_mV, int vref_mV, int vref1_mV) { struct device *dev = regmap_get_device(data->regmap); int tmp_vref; mcp47feb02_init_scale(data, MCP47FEB02_SCALE_VDD, vdd_mV, data->scale); if (data->use_vref) tmp_vref = vref_mV; else tmp_vref = MCP47FEB02_INTERNAL_BAND_GAP_mV; mcp47feb02_init_scale(data, MCP47FEB02_SCALE_GAIN_X1, tmp_vref, data->scale); mcp47feb02_init_scale(data, MCP47FEB02_SCALE_GAIN_X2, tmp_vref * 2, data->scale); if (data->phys_channels >= 4) { mcp47feb02_init_scale(data, MCP47FEB02_SCALE_VDD, vdd_mV, data->scale_1); if (data->use_vref1 && vref1_mV <= 0) return dev_err_probe(dev, vref1_mV, "Invalid voltage for Vref1\n"); if (data->use_vref1) tmp_vref = vref1_mV; else tmp_vref = MCP47FEB02_INTERNAL_BAND_GAP_mV; mcp47feb02_init_scale(data, MCP47FEB02_SCALE_GAIN_X1, tmp_vref, data->scale_1); mcp47feb02_init_scale(data, MCP47FEB02_SCALE_GAIN_X2, tmp_vref * 2, data->scale_1); } return 0; } static int mcp47feb02_read_avail(struct iio_dev *indio_dev, struct iio_chan_spec const *ch, const int **vals, int *type, int *length, long info) { struct mcp47feb02_data *data = iio_priv(indio_dev); switch (info) { case IIO_CHAN_INFO_SCALE: switch (ch->type) { case IIO_VOLTAGE: if (data->phys_channels >= 4 && (ch->address % 2)) *vals = data->scale_1; else *vals = data->scale; *length = 2 * MCP47FEB02_MAX_SCALES_CH; *type = IIO_VAL_INT_PLUS_MICRO; return IIO_AVAIL_LIST; default: return -EINVAL; } default: return -EINVAL; } } static void mcp47feb02_get_scale(int ch, struct mcp47feb02_data *data, int *val, int *val2) { enum mcp47feb02_scale current_scale; if (data->chdata[ch].ref_mode == MCP47FEB02_VREF_VDD) current_scale = MCP47FEB02_SCALE_VDD; else if (data->chdata[ch].use_2x_gain) current_scale = MCP47FEB02_SCALE_GAIN_X2; else current_scale = MCP47FEB02_SCALE_GAIN_X1; if (data->phys_channels >= 4 && (ch % 2)) { *val = data->scale_1[current_scale * 2]; *val2 = data->scale_1[current_scale * 2 + 1]; } else { *val = data->scale[current_scale * 2]; *val2 = data->scale[current_scale * 2 + 1]; } } static int mcp47feb02_check_scale(struct mcp47feb02_data *data, int val, int val2, int scale[]) { unsigned int i; for (i = 0; i < MCP47FEB02_MAX_SCALES_CH; i++) { if (scale[i * 2] == val && scale[i * 2 + 1] == val2) return i; } return -EINVAL; } static int mcp47feb02_ch_scale(struct mcp47feb02_data *data, int ch, int scale) { int tmp_val, ret; if (scale == MCP47FEB02_SCALE_VDD) { tmp_val = MCP47FEB02_VREF_VDD; } else if (data->phys_channels >= 4 && (ch % 2)) { if (data->use_vref1) { if (data->vref1_buffered) tmp_val = MCP47FEB02_EXTERNAL_VREF_BUFFERED; else tmp_val = MCP47FEB02_EXTERNAL_VREF_UNBUFFERED; } else { tmp_val = MCP47FEB02_INTERNAL_BAND_GAP; } } else if (data->use_vref) { if (data->vref_buffered) tmp_val = MCP47FEB02_EXTERNAL_VREF_BUFFERED; else tmp_val = MCP47FEB02_EXTERNAL_VREF_UNBUFFERED; } else { tmp_val = MCP47FEB02_INTERNAL_BAND_GAP; } ret = regmap_update_bits(data->regmap, MCP47FEB02_VREF_REG_ADDR, DAC_CTRL_MASK(ch), DAC_CTRL_VAL(ch, tmp_val)); if (ret) return ret; data->chdata[ch].ref_mode = tmp_val; return 0; } /* * Setting the scale in order to choose between VDD and (Vref or Band Gap) from the user * space. The VREF pin is either an input or an output, therefore the user cannot * simultaneously connect an external voltage reference to the pin and select the * internal Band Gap. * When the DAC’s voltage reference is configured as the VREF pin, the pin is an input. * When the DAC’s voltage reference is configured as the internal Band Gap, * the VREF pin is an output. * If Vref/Vref1 voltage is not available, then the internal Band Gap will be used * to calculate the values for the scale. */ static int mcp47feb02_set_scale(struct mcp47feb02_data *data, int ch, int scale) { int tmp_val, ret; ret = mcp47feb02_ch_scale(data, ch, scale); if (ret) return ret; if (scale == MCP47FEB02_SCALE_GAIN_X2) tmp_val = MCP47FEB02_GAIN_BIT_X2; else tmp_val = MCP47FEB02_GAIN_BIT_X1; ret = regmap_update_bits(data->regmap, MCP47FEB02_GAIN_CTRL_STATUS_REG_ADDR, DAC_GAIN_MASK(ch), DAC_GAIN_VAL(ch, tmp_val)); if (ret) return ret; data->chdata[ch].use_2x_gain = tmp_val; return 0; } static int mcp47feb02_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *ch, int *val, int *val2, long mask) { struct mcp47feb02_data *data = iio_priv(indio_dev); int ret; switch (mask) { case IIO_CHAN_INFO_RAW: ret = regmap_read(data->regmap, REG_ADDR(ch->address), val); if (ret) return ret; return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: mcp47feb02_get_scale(ch->address, data, val, val2); return IIO_VAL_INT_PLUS_MICRO; default: return -EINVAL; } } static int mcp47feb02_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *ch, int val, int val2, long mask) { struct mcp47feb02_data *data = iio_priv(indio_dev); int *tmp_scale, ret; guard(mutex)(&data->lock); switch (mask) { case IIO_CHAN_INFO_RAW: ret = regmap_write(data->regmap, REG_ADDR(ch->address), val); if (ret) return ret; data->chdata[ch->address].dac_data = val; return 0; case IIO_CHAN_INFO_SCALE: if (data->phys_channels >= 4 && (ch->address % 2)) tmp_scale = data->scale_1; else tmp_scale = data->scale; ret = mcp47feb02_check_scale(data, val, val2, tmp_scale); if (ret < 0) return ret; return mcp47feb02_set_scale(data, ch->address, ret); default: return -EINVAL; } } static int mcp47feb02_read_label(struct iio_dev *indio_dev, struct iio_chan_spec const *ch, char *label) { struct mcp47feb02_data *data = iio_priv(indio_dev); return sysfs_emit(label, "%s\n", data->labels[ch->address]); } static const struct iio_info mcp47feb02_info = { .read_raw = mcp47feb02_read_raw, .write_raw = mcp47feb02_write_raw, .read_label = mcp47feb02_read_label, .read_avail = &mcp47feb02_read_avail, .attrs = &mcp47feb02_attribute_group, }; static const struct iio_info mcp47fvb02_info = { .read_raw = mcp47feb02_read_raw, .write_raw = mcp47feb02_write_raw, .read_label = mcp47feb02_read_label, .read_avail = &mcp47feb02_read_avail, }; static int mcp47feb02_parse_fw(struct iio_dev *indio_dev, const struct mcp47feb02_features *chip_features) { struct iio_chan_spec chanspec = mcp47febxx_ch_template; struct mcp47feb02_data *data = iio_priv(indio_dev); struct device *dev = regmap_get_device(data->regmap); struct iio_chan_spec *channels; u32 num_channels; u8 chan_idx = 0; guard(mutex)(&data->lock); num_channels = device_get_child_node_count(dev); if (num_channels > chip_features->phys_channels) return dev_err_probe(dev, -EINVAL, "More channels than the chip supports\n"); if (!num_channels) return dev_err_probe(dev, -EINVAL, "No channel specified in the devicetree.\n"); channels = devm_kcalloc(dev, num_channels, sizeof(*channels), GFP_KERNEL); if (!channels) return -ENOMEM; device_for_each_child_node_scoped(dev, child) { u32 reg = 0; int ret; ret = fwnode_property_read_u32(child, "reg", ®); if (ret) return dev_err_probe(dev, ret, "Invalid channel number\n"); if (reg >= chip_features->phys_channels) return dev_err_probe(dev, -EINVAL, "The index of the channels does not match the chip\n"); set_bit(reg, &data->active_channels_mask); ret = fwnode_property_read_string(child, "label", &data->labels[reg]); if (ret) return dev_err_probe(dev, ret, "%pfw: invalid label\n", fwnode_get_name(child)); chanspec.address = reg; chanspec.channel = reg; channels[chan_idx] = chanspec; chan_idx++; } indio_dev->num_channels = num_channels; indio_dev->channels = channels; indio_dev->modes = INDIO_DIRECT_MODE; data->phys_channels = chip_features->phys_channels; data->vref_buffered = device_property_read_bool(dev, "microchip,vref-buffered"); if (chip_features->have_ext_vref1) data->vref1_buffered = device_property_read_bool(dev, "microchip,vref1-buffered"); return 0; } static int mcp47feb02_init_ctrl_regs(struct mcp47feb02_data *data) { unsigned int i, vref_ch, gain_ch, pd_ch; int ret; ret = regmap_read(data->regmap, MCP47FEB02_VREF_REG_ADDR, &vref_ch); if (ret) return ret; ret = regmap_read(data->regmap, MCP47FEB02_GAIN_CTRL_STATUS_REG_ADDR, &gain_ch); if (ret) return ret; ret = regmap_read(data->regmap, MCP47FEB02_POWER_DOWN_REG_ADDR, &pd_ch); if (ret) return ret; gain_ch = gain_ch & MCP47FEB02_GAIN_BITS_MASK; for_each_set_bit(i, &data->active_channels_mask, data->phys_channels) { struct device *dev = regmap_get_device(data->regmap); unsigned int pd_tmp; data->chdata[i].ref_mode = (vref_ch >> (2 * i)) & MCP47FEB02_DAC_CTRL_MASK; data->chdata[i].use_2x_gain = (gain_ch >> i) & MCP47FEB02_GAIN_BIT_MASK; /* * Inform the user that the current voltage reference read from the volatile * register of the chip is different from the one specified in the device tree. * Considering that the user cannot have an external voltage reference connected * to the pin and select the internal Band Gap at the same time, in order to avoid * miscofiguring the reference voltage, the volatile register will not be written. * In order to overwrite the setting from volatile register with the one from the * device tree, the user needs to write the chosen scale. */ switch (data->chdata[i].ref_mode) { case MCP47FEB02_INTERNAL_BAND_GAP: if (data->phys_channels >= 4 && (i % 2) && data->use_vref1) { dev_dbg(dev, "ch[%u]: was configured to use internal band gap", i); dev_dbg(dev, "ch[%u]: reference voltage set to VREF1", i); break; } if ((data->phys_channels < 4 || (data->phys_channels >= 4 && !(i % 2))) && data->use_vref) { dev_dbg(dev, "ch[%u]: was configured to use internal band gap", i); dev_dbg(dev, "ch[%u]: reference voltage set to VREF", i); break; } break; case MCP47FEB02_EXTERNAL_VREF_UNBUFFERED: case MCP47FEB02_EXTERNAL_VREF_BUFFERED: if (data->phys_channels >= 4 && (i % 2) && !data->use_vref1) { dev_dbg(dev, "ch[%u]: was configured to use VREF1", i); dev_dbg(dev, "ch[%u]: reference voltage set to internal band gap", i); break; } if ((data->phys_channels < 4 || (data->phys_channels >= 4 && !(i % 2))) && !data->use_vref) { dev_dbg(dev, "ch[%u]: was configured to use VREF", i); dev_dbg(dev, "ch[%u]: reference voltage set to internal band gap", i); break; } break; } pd_tmp = (pd_ch >> (2 * i)) & MCP47FEB02_DAC_CTRL_MASK; data->chdata[i].powerdown_mode = pd_tmp ? (pd_tmp - 1) : pd_tmp; data->chdata[i].powerdown = !!(data->chdata[i].powerdown_mode); } return 0; } static int mcp47feb02_init_ch_scales(struct mcp47feb02_data *data, int vdd_mV, int vref_mV, int vref1_mV) { unsigned int i; for_each_set_bit(i, &data->active_channels_mask, data->phys_channels) { struct device *dev = regmap_get_device(data->regmap); int ret; ret = mcp47feb02_init_scales_avail(data, vdd_mV, vref_mV, vref1_mV); if (ret) return dev_err_probe(dev, ret, "failed to init scales for ch %u\n", i); } return 0; } static int mcp47feb02_probe(struct i2c_client *client) { const struct mcp47feb02_features *chip_features; struct device *dev = &client->dev; struct mcp47feb02_data *data; struct iio_dev *indio_dev; int vref1_mV = 0; int vref_mV = 0; int vdd_mV; int ret; indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); if (!indio_dev) return -ENOMEM; data = iio_priv(indio_dev); chip_features = i2c_get_match_data(client); if (!chip_features) return -EINVAL; data->chip_features = chip_features; if (chip_features->have_eeprom) { data->regmap = devm_regmap_init_i2c(client, &mcp47feb02_regmap_config); indio_dev->info = &mcp47feb02_info; } else { data->regmap = devm_regmap_init_i2c(client, &mcp47fvb02_regmap_config); indio_dev->info = &mcp47fvb02_info; } if (IS_ERR(data->regmap)) return dev_err_probe(dev, PTR_ERR(data->regmap), "Error initializing i2c regmap\n"); indio_dev->name = chip_features->name; ret = mcp47feb02_parse_fw(indio_dev, chip_features); if (ret) return dev_err_probe(dev, ret, "Error parsing firmware data\n"); ret = devm_mutex_init(dev, &data->lock); if (ret) return ret; ret = devm_regulator_get_enable_read_voltage(dev, "vdd"); if (ret < 0) return ret; vdd_mV = ret / MILLI; ret = devm_regulator_get_enable_read_voltage(dev, "vref"); if (ret > 0) { vref_mV = ret / MILLI; data->use_vref = true; } else { dev_dbg(dev, "using internal band gap as voltage reference.\n"); dev_dbg(dev, "Vref is unavailable.\n"); } if (chip_features->have_ext_vref1) { ret = devm_regulator_get_enable_read_voltage(dev, "vref1"); if (ret > 0) { vref1_mV = ret / MILLI; data->use_vref1 = true; } else { dev_dbg(dev, "using internal band gap as voltage reference 1.\n"); dev_dbg(dev, "Vref1 is unavailable.\n"); } } ret = mcp47feb02_init_ctrl_regs(data); if (ret) return dev_err_probe(dev, ret, "Error initialising vref register\n"); ret = mcp47feb02_init_ch_scales(data, vdd_mV, vref_mV, vref1_mV); if (ret) return ret; return devm_iio_device_register(dev, indio_dev); } static const struct i2c_device_id mcp47feb02_id[] = { { "mcp47feb01", (kernel_ulong_t)&mcp47feb01_chip_features }, { "mcp47feb02", (kernel_ulong_t)&mcp47feb02_chip_features }, { "mcp47feb04", (kernel_ulong_t)&mcp47feb04_chip_features }, { "mcp47feb08", (kernel_ulong_t)&mcp47feb08_chip_features }, { "mcp47feb11", (kernel_ulong_t)&mcp47feb11_chip_features }, { "mcp47feb12", (kernel_ulong_t)&mcp47feb12_chip_features }, { "mcp47feb14", (kernel_ulong_t)&mcp47feb14_chip_features }, { "mcp47feb18", (kernel_ulong_t)&mcp47feb18_chip_features }, { "mcp47feb21", (kernel_ulong_t)&mcp47feb21_chip_features }, { "mcp47feb22", (kernel_ulong_t)&mcp47feb22_chip_features }, { "mcp47feb24", (kernel_ulong_t)&mcp47feb24_chip_features }, { "mcp47feb28", (kernel_ulong_t)&mcp47feb28_chip_features }, { "mcp47fvb01", (kernel_ulong_t)&mcp47fvb01_chip_features }, { "mcp47fvb02", (kernel_ulong_t)&mcp47fvb02_chip_features }, { "mcp47fvb04", (kernel_ulong_t)&mcp47fvb04_chip_features }, { "mcp47fvb08", (kernel_ulong_t)&mcp47fvb08_chip_features }, { "mcp47fvb11", (kernel_ulong_t)&mcp47fvb11_chip_features }, { "mcp47fvb12", (kernel_ulong_t)&mcp47fvb12_chip_features }, { "mcp47fvb14", (kernel_ulong_t)&mcp47fvb14_chip_features }, { "mcp47fvb18", (kernel_ulong_t)&mcp47fvb18_chip_features }, { "mcp47fvb21", (kernel_ulong_t)&mcp47fvb21_chip_features }, { "mcp47fvb22", (kernel_ulong_t)&mcp47fvb22_chip_features }, { "mcp47fvb24", (kernel_ulong_t)&mcp47fvb24_chip_features }, { "mcp47fvb28", (kernel_ulong_t)&mcp47fvb28_chip_features }, { } }; MODULE_DEVICE_TABLE(i2c, mcp47feb02_id); static const struct of_device_id mcp47feb02_of_match[] = { { .compatible = "microchip,mcp47feb01", .data = &mcp47feb01_chip_features }, { .compatible = "microchip,mcp47feb02", .data = &mcp47feb02_chip_features }, { .compatible = "microchip,mcp47feb04", .data = &mcp47feb04_chip_features }, { .compatible = "microchip,mcp47feb08", .data = &mcp47feb08_chip_features }, { .compatible = "microchip,mcp47feb11", .data = &mcp47feb11_chip_features }, { .compatible = "microchip,mcp47feb12", .data = &mcp47feb12_chip_features }, { .compatible = "microchip,mcp47feb14", .data = &mcp47feb14_chip_features }, { .compatible = "microchip,mcp47feb18", .data = &mcp47feb18_chip_features }, { .compatible = "microchip,mcp47feb21", .data = &mcp47feb21_chip_features }, { .compatible = "microchip,mcp47feb22", .data = &mcp47feb22_chip_features }, { .compatible = "microchip,mcp47feb24", .data = &mcp47feb24_chip_features }, { .compatible = "microchip,mcp47feb28", .data = &mcp47feb28_chip_features }, { .compatible = "microchip,mcp47fvb01", .data = &mcp47fvb01_chip_features }, { .compatible = "microchip,mcp47fvb02", .data = &mcp47fvb02_chip_features }, { .compatible = "microchip,mcp47fvb04", .data = &mcp47fvb04_chip_features }, { .compatible = "microchip,mcp47fvb08", .data = &mcp47fvb08_chip_features }, { .compatible = "microchip,mcp47fvb11", .data = &mcp47fvb11_chip_features }, { .compatible = "microchip,mcp47fvb12", .data = &mcp47fvb12_chip_features }, { .compatible = "microchip,mcp47fvb14", .data = &mcp47fvb14_chip_features }, { .compatible = "microchip,mcp47fvb18", .data = &mcp47fvb18_chip_features }, { .compatible = "microchip,mcp47fvb21", .data = &mcp47fvb21_chip_features }, { .compatible = "microchip,mcp47fvb22", .data = &mcp47fvb22_chip_features }, { .compatible = "microchip,mcp47fvb24", .data = &mcp47fvb24_chip_features }, { .compatible = "microchip,mcp47fvb28", .data = &mcp47fvb28_chip_features }, { } }; MODULE_DEVICE_TABLE(of, mcp47feb02_of_match); static struct i2c_driver mcp47feb02_driver = { .driver = { .name = "mcp47feb02", .of_match_table = mcp47feb02_of_match, .pm = pm_sleep_ptr(&mcp47feb02_pm_ops), }, .probe = mcp47feb02_probe, .id_table = mcp47feb02_id, }; module_i2c_driver(mcp47feb02_driver); MODULE_AUTHOR("Ariana Lazar "); MODULE_DESCRIPTION("IIO driver for MCP47FEB02 Multi-Channel DAC with I2C interface"); MODULE_LICENSE("GPL");