From 6f7cadcf664b04df3b2e9b9c6d65bf626aa1b411 Mon Sep 17 00:00:00 2001 From: Cosmin Tanislav Date: Thu, 3 Nov 2022 15:00:41 +0200 Subject: [PATCH] iio: temperature: ltc2983: support more parts Add support for the following parts: * LTC2984 * LTC2986 * LTM2985 The LTC2984 is a variant of the LTC2983 with EEPROM. The LTC2986 is a variant of the LTC2983 with only 10 channels, EEPROM and support for active analog temperature sensors. The LTM2985 is software-compatible with the LTC2986. Signed-off-by: Cosmin Tanislav Link: https://lore.kernel.org/r/20221103130041.2153295-14-demonsingur@gmail.com Signed-off-by: Jonathan Cameron --- drivers/iio/temperature/ltc2983.c | 183 ++++++++++++++++++++++++++++-- 1 file changed, 176 insertions(+), 7 deletions(-) diff --git a/drivers/iio/temperature/ltc2983.c b/drivers/iio/temperature/ltc2983.c index 1117991ca2ab..fcb96c44d954 100644 --- a/drivers/iio/temperature/ltc2983.c +++ b/drivers/iio/temperature/ltc2983.c @@ -25,9 +25,12 @@ #define LTC2983_STATUS_REG 0x0000 #define LTC2983_TEMP_RES_START_REG 0x0010 #define LTC2983_TEMP_RES_END_REG 0x005F +#define LTC2983_EEPROM_KEY_REG 0x00B0 +#define LTC2983_EEPROM_READ_STATUS_REG 0x00D0 #define LTC2983_GLOBAL_CONFIG_REG 0x00F0 #define LTC2983_MULT_CHANNEL_START_REG 0x00F4 #define LTC2983_MULT_CHANNEL_END_REG 0x00F7 +#define LTC2986_EEPROM_STATUS_REG 0x00F9 #define LTC2983_MUX_CONFIG_REG 0x00FF #define LTC2983_CHAN_ASSIGN_START_REG 0x0200 #define LTC2983_CHAN_ASSIGN_END_REG 0x024F @@ -35,13 +38,21 @@ #define LTC2983_CUST_SENS_TBL_END_REG 0x03CF #define LTC2983_DIFFERENTIAL_CHAN_MIN 2 -#define LTC2983_MAX_CHANNELS_NR 20 #define LTC2983_MIN_CHANNELS_NR 1 #define LTC2983_SLEEP 0x97 #define LTC2983_CUSTOM_STEINHART_SIZE 24 #define LTC2983_CUSTOM_SENSOR_ENTRY_SZ 6 #define LTC2983_CUSTOM_STEINHART_ENTRY_SZ 4 +#define LTC2983_EEPROM_KEY 0xA53C0F5A +#define LTC2983_EEPROM_WRITE_CMD 0x15 +#define LTC2983_EEPROM_READ_CMD 0x16 +#define LTC2983_EEPROM_STATUS_FAILURE_MASK GENMASK(3, 1) +#define LTC2983_EEPROM_READ_FAILURE_MASK GENMASK(7, 0) + +#define LTC2983_EEPROM_WRITE_TIME_MS 2600 +#define LTC2983_EEPROM_READ_TIME_MS 20 + #define LTC2983_CHAN_START_ADDR(chan) \ (((chan - 1) * 4) + LTC2983_CHAN_ASSIGN_START_REG) #define LTC2983_CHAN_RES_ADDR(chan) \ @@ -171,6 +182,7 @@ enum { LTC2983_SENSOR_DIODE = 28, LTC2983_SENSOR_SENSE_RESISTOR = 29, LTC2983_SENSOR_DIRECT_ADC = 30, + LTC2983_SENSOR_ACTIVE_TEMP = 31, }; #define to_thermocouple(_sensor) \ @@ -191,7 +203,17 @@ enum { #define to_adc(_sensor) \ container_of(_sensor, struct ltc2983_adc, sensor) +#define to_temp(_sensor) \ + container_of(_sensor, struct ltc2983_temp, sensor) + +struct ltc2983_chip_info { + unsigned int max_channels_nr; + bool has_temp; + bool has_eeprom; +}; + struct ltc2983_data { + const struct ltc2983_chip_info *info; struct regmap *regmap; struct spi_device *spi; struct mutex lock; @@ -210,6 +232,7 @@ struct ltc2983_data { */ __be32 temp __aligned(IIO_DMA_MINALIGN); __be32 chan_val; + __be32 eeprom_key; }; struct ltc2983_sensor { @@ -272,6 +295,12 @@ struct ltc2983_adc { bool single_ended; }; +struct ltc2983_temp { + struct ltc2983_sensor sensor; + struct ltc2983_custom_sensor *custom; + bool single_ended; +}; + /* * Convert to Q format numbers. These number's are integers where * the number of integer and fractional bits are specified. The resolution @@ -606,6 +635,22 @@ static int ltc2983_adc_assign_chan(struct ltc2983_data *st, return __ltc2983_chan_assign_common(st, sensor, chan_val); } +static int ltc2983_temp_assign_chan(struct ltc2983_data *st, + const struct ltc2983_sensor *sensor) +{ + struct ltc2983_temp *temp = to_temp(sensor); + u32 chan_val; + int ret; + + chan_val = LTC2983_ADC_SINGLE_ENDED(temp->single_ended); + + ret = __ltc2983_chan_custom_sensor_assign(st, temp->custom, &chan_val); + if (ret) + return ret; + + return __ltc2983_chan_assign_common(st, sensor, chan_val); +} + static struct ltc2983_sensor * ltc2983_thermocouple_new(const struct fwnode_handle *child, struct ltc2983_data *st, const struct ltc2983_sensor *sensor) @@ -771,10 +816,10 @@ ltc2983_rtd_new(const struct fwnode_handle *child, struct ltc2983_data *st, if (rtd->sensor_config & LTC2983_RTD_4_WIRE_MASK) { /* 4-wire */ u8 min = LTC2983_DIFFERENTIAL_CHAN_MIN, - max = LTC2983_MAX_CHANNELS_NR; + max = st->info->max_channels_nr; if (rtd->sensor_config & LTC2983_RTD_ROTATION_MASK) - max = LTC2983_MAX_CHANNELS_NR - 1; + max = st->info->max_channels_nr - 1; if (((rtd->sensor_config & LTC2983_RTD_KELVIN_R_SENSE_MASK) == LTC2983_RTD_KELVIN_R_SENSE_MASK) && @@ -1143,6 +1188,38 @@ static struct ltc2983_sensor *ltc2983_adc_new(struct fwnode_handle *child, return &adc->sensor; } +static struct ltc2983_sensor *ltc2983_temp_new(struct fwnode_handle *child, + struct ltc2983_data *st, + const struct ltc2983_sensor *sensor) +{ + struct ltc2983_temp *temp; + + temp = devm_kzalloc(&st->spi->dev, sizeof(*temp), GFP_KERNEL); + if (!temp) + return ERR_PTR(-ENOMEM); + + if (fwnode_property_read_bool(child, "adi,single-ended")) + temp->single_ended = true; + + if (!temp->single_ended && + sensor->chan < LTC2983_DIFFERENTIAL_CHAN_MIN) { + dev_err(&st->spi->dev, "Invalid chan:%d for differential temp\n", + sensor->chan); + return ERR_PTR(-EINVAL); + } + + temp->custom = __ltc2983_custom_sensor_new(st, child, "adi,custom-temp", + false, 4096, true); + if (IS_ERR(temp->custom)) + return ERR_CAST(temp->custom); + + /* set common parameters */ + temp->sensor.assign_chan = ltc2983_temp_assign_chan; + temp->sensor.fault_handler = ltc2983_common_fault_handler; + + return &temp->sensor; +} + static int ltc2983_chan_read(struct ltc2983_data *st, const struct ltc2983_sensor *sensor, int *val) { @@ -1302,10 +1379,10 @@ static int ltc2983_parse_dt(struct ltc2983_data *st) /* check if we have a valid channel */ if (sensor.chan < LTC2983_MIN_CHANNELS_NR || - sensor.chan > LTC2983_MAX_CHANNELS_NR) { + sensor.chan > st->info->max_channels_nr) { ret = -EINVAL; dev_err(dev, "chan:%d must be from %u to %u\n", sensor.chan, - LTC2983_MIN_CHANNELS_NR, LTC2983_MAX_CHANNELS_NR); + LTC2983_MIN_CHANNELS_NR, st->info->max_channels_nr); goto put_child; } else if (channel_avail_mask & BIT(sensor.chan)) { ret = -EINVAL; @@ -1345,6 +1422,9 @@ static int ltc2983_parse_dt(struct ltc2983_data *st) st->iio_channels--; } else if (sensor.type == LTC2983_SENSOR_DIRECT_ADC) { st->sensors[chan] = ltc2983_adc_new(child, st, &sensor); + } else if (st->info->has_temp && + sensor.type == LTC2983_SENSOR_ACTIVE_TEMP) { + st->sensors[chan] = ltc2983_temp_new(child, st, &sensor); } else { dev_err(dev, "Unknown sensor type %d\n", sensor.type); ret = -EINVAL; @@ -1371,6 +1451,45 @@ static int ltc2983_parse_dt(struct ltc2983_data *st) return ret; } +static int ltc2983_eeprom_cmd(struct ltc2983_data *st, unsigned int cmd, + unsigned int wait_time, unsigned int status_reg, + unsigned long status_fail_mask) +{ + unsigned long time; + unsigned int val; + int ret; + + ret = regmap_bulk_write(st->regmap, LTC2983_EEPROM_KEY_REG, + &st->eeprom_key, sizeof(st->eeprom_key)); + if (ret) + return ret; + + reinit_completion(&st->completion); + + ret = regmap_write(st->regmap, LTC2983_STATUS_REG, + LTC2983_STATUS_START(true) | cmd); + if (ret) + return ret; + + time = wait_for_completion_timeout(&st->completion, + msecs_to_jiffies(wait_time)); + if (!time) { + dev_err(&st->spi->dev, "EEPROM command timed out\n"); + return -ETIMEDOUT; + } + + ret = regmap_read(st->regmap, status_reg, &val); + if (ret) + return ret; + + if (val & status_fail_mask) { + dev_err(&st->spi->dev, "EEPROM command failed: 0x%02X\n", val); + return -EINVAL; + } + + return 0; +} + static int ltc2983_setup(struct ltc2983_data *st, bool assign_iio) { u32 iio_chan_t = 0, iio_chan_v = 0, chan, iio_idx = 0, status; @@ -1396,6 +1515,15 @@ static int ltc2983_setup(struct ltc2983_data *st, bool assign_iio) if (ret) return ret; + if (st->info->has_eeprom && !assign_iio) { + ret = ltc2983_eeprom_cmd(st, LTC2983_EEPROM_READ_CMD, + LTC2983_EEPROM_READ_TIME_MS, + LTC2983_EEPROM_READ_STATUS_REG, + LTC2983_EEPROM_READ_FAILURE_MASK); + if (!ret) + return 0; + } + for (chan = 0; chan < st->num_channels; chan++) { u32 chan_type = 0, *iio_chan; @@ -1435,9 +1563,13 @@ static int ltc2983_setup(struct ltc2983_data *st, bool assign_iio) static const struct regmap_range ltc2983_reg_ranges[] = { regmap_reg_range(LTC2983_STATUS_REG, LTC2983_STATUS_REG), regmap_reg_range(LTC2983_TEMP_RES_START_REG, LTC2983_TEMP_RES_END_REG), + regmap_reg_range(LTC2983_EEPROM_KEY_REG, LTC2983_EEPROM_KEY_REG), + regmap_reg_range(LTC2983_EEPROM_READ_STATUS_REG, + LTC2983_EEPROM_READ_STATUS_REG), regmap_reg_range(LTC2983_GLOBAL_CONFIG_REG, LTC2983_GLOBAL_CONFIG_REG), regmap_reg_range(LTC2983_MULT_CHANNEL_START_REG, LTC2983_MULT_CHANNEL_END_REG), + regmap_reg_range(LTC2986_EEPROM_STATUS_REG, LTC2986_EEPROM_STATUS_REG), regmap_reg_range(LTC2983_MUX_CONFIG_REG, LTC2983_MUX_CONFIG_REG), regmap_reg_range(LTC2983_CHAN_ASSIGN_START_REG, LTC2983_CHAN_ASSIGN_END_REG), @@ -1482,6 +1614,12 @@ static int ltc2983_probe(struct spi_device *spi) st = iio_priv(indio_dev); + st->info = device_get_match_data(&spi->dev); + if (!st->info) + st->info = (void *)spi_get_device_id(spi)->driver_data; + if (!st->info) + return -ENODEV; + st->regmap = devm_regmap_init_spi(spi, <c2983_regmap_config); if (IS_ERR(st->regmap)) { dev_err(&spi->dev, "Failed to initialize regmap\n"); @@ -1491,6 +1629,7 @@ static int ltc2983_probe(struct spi_device *spi) mutex_init(&st->lock); init_completion(&st->completion); st->spi = spi; + st->eeprom_key = cpu_to_be32(LTC2983_EEPROM_KEY); spi_set_drvdata(spi, st); ret = ltc2983_parse_dt(st); @@ -1524,6 +1663,15 @@ static int ltc2983_probe(struct spi_device *spi) return ret; } + if (st->info->has_eeprom) { + ret = ltc2983_eeprom_cmd(st, LTC2983_EEPROM_WRITE_CMD, + LTC2983_EEPROM_WRITE_TIME_MS, + LTC2986_EEPROM_STATUS_REG, + LTC2983_EEPROM_STATUS_FAILURE_MASK); + if (ret) + return ret; + } + indio_dev->name = name; indio_dev->num_channels = st->iio_channels; indio_dev->channels = st->iio_chan; @@ -1554,14 +1702,35 @@ static int ltc2983_suspend(struct device *dev) static DEFINE_SIMPLE_DEV_PM_OPS(ltc2983_pm_ops, ltc2983_suspend, ltc2983_resume); +static const struct ltc2983_chip_info ltc2983_chip_info_data = { + .max_channels_nr = 20, +}; + +static const struct ltc2983_chip_info ltc2984_chip_info_data = { + .max_channels_nr = 20, + .has_eeprom = true, +}; + +static const struct ltc2983_chip_info ltc2986_chip_info_data = { + .max_channels_nr = 10, + .has_temp = true, + .has_eeprom = true, +}; + static const struct spi_device_id ltc2983_id_table[] = { - { "ltc2983" }, + { "ltc2983", (kernel_ulong_t)<c2983_chip_info_data }, + { "ltc2984", (kernel_ulong_t)<c2984_chip_info_data }, + { "ltc2986", (kernel_ulong_t)<c2986_chip_info_data }, + { "ltm2985", (kernel_ulong_t)<c2986_chip_info_data }, {}, }; MODULE_DEVICE_TABLE(spi, ltc2983_id_table); static const struct of_device_id ltc2983_of_match[] = { - { .compatible = "adi,ltc2983" }, + { .compatible = "adi,ltc2983", .data = <c2983_chip_info_data }, + { .compatible = "adi,ltc2984", .data = <c2984_chip_info_data }, + { .compatible = "adi,ltc2986", .data = <c2986_chip_info_data }, + { .compatible = "adi,ltm2985", .data = <c2986_chip_info_data }, {}, }; MODULE_DEVICE_TABLE(of, ltc2983_of_match);