mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

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 <cosmin.tanislav@analog.com>
Link: https://lore.kernel.org/r/20221103130041.2153295-14-demonsingur@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Cosmin Tanislav 2022-11-03 15:00:41 +02:00 committed by Jonathan Cameron
parent d240526950
commit 6f7cadcf66
1 changed files with 176 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

183
drivers/iio/temperature/ltc2983.c
View File

@ -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 @@ put_child:
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, &ltc2983_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)&ltc2983_chip_info_data },
{ "ltc2984", (kernel_ulong_t)&ltc2984_chip_info_data },
{ "ltc2986", (kernel_ulong_t)&ltc2986_chip_info_data },
{ "ltm2985", (kernel_ulong_t)&ltc2986_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 = &ltc2983_chip_info_data },
{ .compatible = "adi,ltc2984", .data = &ltc2984_chip_info_data },
{ .compatible = "adi,ltc2986", .data = &ltc2986_chip_info_data },
{ .compatible = "adi,ltm2985", .data = &ltc2986_chip_info_data },
{},
};
MODULE_DEVICE_TABLE(of, ltc2983_of_match);