The LTC2499 is a 16-channel (eight differential), 24-bit, ADC with Easy Drive technology and a 2-wire, I2C interface. Implement support for the LTC2499 ADC by extending the LTC2497 driver. A new chip_info struct is added to differentiate between chip types and resolutions when reading data from the device. Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/2499fe.pdf Signed-off-by: Ciprian Regus <ciprian.regus@xxxxxxxxxx> --- drivers/iio/adc/ltc2496.c | 8 +++++++- drivers/iio/adc/ltc2497-core.c | 2 +- drivers/iio/adc/ltc2497.c | 34 +++++++++++++++++++++++++++++----- drivers/iio/adc/ltc2497.h | 13 ++++++++++++- 4 files changed, 49 insertions(+), 8 deletions(-) diff --git a/drivers/iio/adc/ltc2496.c b/drivers/iio/adc/ltc2496.c index dfb3bb5997e5..98338104c24a 100644 --- a/drivers/iio/adc/ltc2496.c +++ b/drivers/iio/adc/ltc2496.c @@ -14,6 +14,7 @@ #include <linux/iio/iio.h> #include <linux/iio/driver.h> #include <linux/module.h> +#include <linux/property.h> #include <linux/mod_devicetable.h> #include "ltc2497.h" @@ -74,6 +75,7 @@ static int ltc2496_probe(struct spi_device *spi) spi_set_drvdata(spi, indio_dev); st->spi = spi; st->common_ddata.result_and_measure = ltc2496_result_and_measure; + st->common_ddata.chip_info = device_get_match_data(dev); return ltc2497core_probe(dev, indio_dev); } @@ -85,8 +87,12 @@ static void ltc2496_remove(struct spi_device *spi) ltc2497core_remove(indio_dev); } +static struct chip_info ltc2496_info = { + .resolution = 16, +}; + static const struct of_device_id ltc2496_of_match[] = { - { .compatible = "lltc,ltc2496", }, + { .compatible = "lltc,ltc2496", .data = (void *)<c2496_info }, {}, }; MODULE_DEVICE_TABLE(of, ltc2496_of_match); diff --git a/drivers/iio/adc/ltc2497-core.c b/drivers/iio/adc/ltc2497-core.c index 2a485c8a1940..b2752399402c 100644 --- a/drivers/iio/adc/ltc2497-core.c +++ b/drivers/iio/adc/ltc2497-core.c @@ -95,7 +95,7 @@ static int ltc2497core_read_raw(struct iio_dev *indio_dev, return ret; *val = ret / 1000; - *val2 = 17; + *val2 = ddata->chip_info->resolution + 1; return IIO_VAL_FRACTIONAL_LOG2; diff --git a/drivers/iio/adc/ltc2497.c b/drivers/iio/adc/ltc2497.c index f7c786f37ceb..bb5e0d4301e2 100644 --- a/drivers/iio/adc/ltc2497.c +++ b/drivers/iio/adc/ltc2497.c @@ -7,10 +7,14 @@ * Datasheet: http://cds.linear.com/docs/en/datasheet/2497fd.pdf */ +#include <linux/bitfield.h> +#include <linux/bitops.h> + #include <linux/i2c.h> #include <linux/iio/iio.h> #include <linux/iio/driver.h> #include <linux/module.h> +#include <linux/property.h> #include <linux/mod_devicetable.h> #include "ltc2497.h" @@ -19,6 +23,8 @@ struct ltc2497_driverdata { /* this must be the first member */ struct ltc2497core_driverdata common_ddata; struct i2c_client *client; + u32 recv_size; + u32 sub_lsb; /* * DMA (thus cache coherency maintenance) may require the * transfer buffers to live in their own cache lines. @@ -34,13 +40,14 @@ static int ltc2497_result_and_measure(struct ltc2497core_driverdata *ddata, int ret; if (val) { - ret = i2c_master_recv(st->client, (char *)&st->buf, 3); + ret = i2c_master_recv(st->client, (char *)&st->buf, st->recv_size); if (ret < 0) { dev_err(&st->client->dev, "i2c_master_recv failed\n"); return ret; } - *val = (be32_to_cpu(st->buf) >> 14) - (1 << 17); + *val = (be32_to_cpu(st->buf) >> st->sub_lsb) - + BIT(ddata->chip_info->resolution + 1); } ret = i2c_smbus_write_byte(st->client, @@ -54,6 +61,7 @@ static int ltc2497_result_and_measure(struct ltc2497core_driverdata *ddata, static int ltc2497_probe(struct i2c_client *client, const struct i2c_device_id *id) { + u32 resolution; struct iio_dev *indio_dev; struct ltc2497_driverdata *st; struct device *dev = &client->dev; @@ -70,6 +78,11 @@ static int ltc2497_probe(struct i2c_client *client, i2c_set_clientdata(client, indio_dev); st->client = client; st->common_ddata.result_and_measure = ltc2497_result_and_measure; + st->common_ddata.chip_info = device_get_match_data(dev); + + resolution = st->common_ddata.chip_info->resolution; + st->sub_lsb = 31 - (resolution + 1); + st->recv_size = resolution / BITS_PER_BYTE + 1; return ltc2497core_probe(dev, indio_dev); } @@ -83,15 +96,26 @@ static int ltc2497_remove(struct i2c_client *client) return 0; } +static struct chip_info ltc2497_info[] = { + [TYPE_LTC2497] = { + .resolution = 16, + }, + [TYPE_LTC2499] = { + .resolution = 24, + } +}; + static const struct i2c_device_id ltc2497_id[] = { - { "ltc2497", 0 }, + { "ltc2497", TYPE_LTC2497 }, + { "ltc2499", TYPE_LTC2499 }, { } }; MODULE_DEVICE_TABLE(i2c, ltc2497_id); static const struct of_device_id ltc2497_of_match[] = { - { .compatible = "lltc,ltc2497", }, - {}, + { .compatible = "lltc,ltc2497", .data = (void *)<c2497_info[TYPE_LTC2497] }, + { .compatible = "lltc,ltc2499", .data = (void *)<c2497_info[TYPE_LTC2499] }, + {} }; MODULE_DEVICE_TABLE(of, ltc2497_of_match); diff --git a/drivers/iio/adc/ltc2497.h b/drivers/iio/adc/ltc2497.h index d0b42dd6b8ad..f4d939cfd48b 100644 --- a/drivers/iio/adc/ltc2497.h +++ b/drivers/iio/adc/ltc2497.h @@ -4,9 +4,20 @@ #define LTC2497_CONFIG_DEFAULT LTC2497_ENABLE #define LTC2497_CONVERSION_TIME_MS 150ULL +enum chip_type { + TYPE_LTC2496, + TYPE_LTC2497, + TYPE_LTC2499 +}; + +struct chip_info { + u32 resolution; +}; + struct ltc2497core_driverdata { struct regulator *ref; - ktime_t time_prev; + ktime_t time_prev; + const struct chip_info *chip_info; u8 addr_prev; int (*result_and_measure)(struct ltc2497core_driverdata *ddata, u8 address, int *val); -- 2.30.2
