diff options
| -rw-r--r-- | drivers/iio/adc/Makefile | 2 | ||||
| -rw-r--r-- | drivers/iio/adc/ltc2497-core.c | 243 | ||||
| -rw-r--r-- | drivers/iio/adc/ltc2497.c | 234 | ||||
| -rw-r--r-- | drivers/iio/adc/ltc2497.h | 18 |
4 files changed, 288 insertions, 209 deletions
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index bf8354cdbc34..5f8d7ac6bbe2 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -51,7 +51,7 @@ obj-$(CONFIG_LPC18XX_ADC) += lpc18xx_adc.o obj-$(CONFIG_LPC32XX_ADC) += lpc32xx_adc.o obj-$(CONFIG_LTC2471) += ltc2471.o obj-$(CONFIG_LTC2485) += ltc2485.o -obj-$(CONFIG_LTC2497) += ltc2497.o +obj-$(CONFIG_LTC2497) += ltc2497.o ltc2497-core.o obj-$(CONFIG_MAX1027) += max1027.o obj-$(CONFIG_MAX11100) += max11100.o obj-$(CONFIG_MAX1118) += max1118.o diff --git a/drivers/iio/adc/ltc2497-core.c b/drivers/iio/adc/ltc2497-core.c new file mode 100644 index 000000000000..f5f7039caacc --- /dev/null +++ b/drivers/iio/adc/ltc2497-core.c @@ -0,0 +1,243 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * ltc2497-core.c - Common code for Analog Devices/Linear Technology + * LTC2496 and LTC2497 ADCs + * + * Copyright (C) 2017 Analog Devices Inc. + */ + +#include <linux/delay.h> +#include <linux/iio/iio.h> +#include <linux/iio/driver.h> +#include <linux/module.h> +#include <linux/regulator/consumer.h> + +#include "ltc2497.h" + +#define LTC2497_SGL BIT(4) +#define LTC2497_DIFF 0 +#define LTC2497_SIGN BIT(3) + +static int ltc2497core_wait_conv(struct ltc2497core_driverdata *ddata) +{ + s64 time_elapsed; + + time_elapsed = ktime_ms_delta(ktime_get(), ddata->time_prev); + + if (time_elapsed < LTC2497_CONVERSION_TIME_MS) { + /* delay if conversion time not passed + * since last read or write + */ + if (msleep_interruptible( + LTC2497_CONVERSION_TIME_MS - time_elapsed)) + return -ERESTARTSYS; + + return 0; + } + + if (time_elapsed - LTC2497_CONVERSION_TIME_MS <= 0) { + /* We're in automatic mode - + * so the last reading is still not outdated + */ + return 0; + } + + return 1; +} + +static int ltc2497core_read(struct ltc2497core_driverdata *ddata, u8 address, int *val) +{ + int ret; + + ret = ltc2497core_wait_conv(ddata); + if (ret < 0) + return ret; + + if (ret || ddata->addr_prev != address) { + ret = ddata->result_and_measure(ddata, address, NULL); + if (ret < 0) + return ret; + ddata->addr_prev = address; + + if (msleep_interruptible(LTC2497_CONVERSION_TIME_MS)) + return -ERESTARTSYS; + } + + ret = ddata->result_and_measure(ddata, address, val); + if (ret < 0) + return ret; + + ddata->time_prev = ktime_get(); + + return ret; +} + +static int ltc2497core_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct ltc2497core_driverdata *ddata = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + mutex_lock(&indio_dev->mlock); + ret = ltc2497core_read(ddata, chan->address, val); + mutex_unlock(&indio_dev->mlock); + if (ret < 0) + return ret; + + return IIO_VAL_INT; + + case IIO_CHAN_INFO_SCALE: + ret = regulator_get_voltage(ddata->ref); + if (ret < 0) + return ret; + + *val = ret / 1000; + *val2 = 17; + + return IIO_VAL_FRACTIONAL_LOG2; + + default: + return -EINVAL; + } +} + +#define LTC2497_CHAN(_chan, _addr, _ds_name) { \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .channel = (_chan), \ + .address = (_addr | (_chan / 2) | ((_chan & 1) ? LTC2497_SIGN : 0)), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ + .datasheet_name = (_ds_name), \ +} + +#define LTC2497_CHAN_DIFF(_chan, _addr) { \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .channel = (_chan) * 2 + ((_addr) & LTC2497_SIGN ? 1 : 0), \ + .channel2 = (_chan) * 2 + ((_addr) & LTC2497_SIGN ? 0 : 1),\ + .address = (_addr | _chan), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ + .differential = 1, \ +} + +static const struct iio_chan_spec ltc2497core_channel[] = { + LTC2497_CHAN(0, LTC2497_SGL, "CH0"), + LTC2497_CHAN(1, LTC2497_SGL, "CH1"), + LTC2497_CHAN(2, LTC2497_SGL, "CH2"), + LTC2497_CHAN(3, LTC2497_SGL, "CH3"), + LTC2497_CHAN(4, LTC2497_SGL, "CH4"), + LTC2497_CHAN(5, LTC2497_SGL, "CH5"), + LTC2497_CHAN(6, LTC2497_SGL, "CH6"), + LTC2497_CHAN(7, LTC2497_SGL, "CH7"), + LTC2497_CHAN(8, LTC2497_SGL, "CH8"), + LTC2497_CHAN(9, LTC2497_SGL, "CH9"), + LTC2497_CHAN(10, LTC2497_SGL, "CH10"), + LTC2497_CHAN(11, LTC2497_SGL, "CH11"), + LTC2497_CHAN(12, LTC2497_SGL, "CH12"), + LTC2497_CHAN(13, LTC2497_SGL, "CH13"), + LTC2497_CHAN(14, LTC2497_SGL, "CH14"), + LTC2497_CHAN(15, LTC2497_SGL, "CH15"), + LTC2497_CHAN_DIFF(0, LTC2497_DIFF), + LTC2497_CHAN_DIFF(1, LTC2497_DIFF), + LTC2497_CHAN_DIFF(2, LTC2497_DIFF), + LTC2497_CHAN_DIFF(3, LTC2497_DIFF), + LTC2497_CHAN_DIFF(4, LTC2497_DIFF), + LTC2497_CHAN_DIFF(5, LTC2497_DIFF), + LTC2497_CHAN_DIFF(6, LTC2497_DIFF), + LTC2497_CHAN_DIFF(7, LTC2497_DIFF), + LTC2497_CHAN_DIFF(0, LTC2497_DIFF | LTC2497_SIGN), + LTC2497_CHAN_DIFF(1, LTC2497_DIFF | LTC2497_SIGN), + LTC2497_CHAN_DIFF(2, LTC2497_DIFF | LTC2497_SIGN), + LTC2497_CHAN_DIFF(3, LTC2497_DIFF | LTC2497_SIGN), + LTC2497_CHAN_DIFF(4, LTC2497_DIFF | LTC2497_SIGN), + LTC2497_CHAN_DIFF(5, LTC2497_DIFF | LTC2497_SIGN), + LTC2497_CHAN_DIFF(6, LTC2497_DIFF | LTC2497_SIGN), + LTC2497_CHAN_DIFF(7, LTC2497_DIFF | LTC2497_SIGN), +}; + +static const struct iio_info ltc2497core_info = { + .read_raw = ltc2497core_read_raw, +}; + +int ltc2497core_probe(struct device *dev, struct iio_dev *indio_dev) +{ + struct ltc2497core_driverdata *ddata = iio_priv(indio_dev); + int ret; + + indio_dev->dev.parent = dev; + indio_dev->name = dev_name(dev); + indio_dev->info = <c2497core_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = ltc2497core_channel; + indio_dev->num_channels = ARRAY_SIZE(ltc2497core_channel); + + ret = ddata->result_and_measure(ddata, LTC2497_CONFIG_DEFAULT, NULL); + if (ret < 0) + return ret; + + ddata->ref = devm_regulator_get(dev, "vref"); + if (IS_ERR(ddata->ref)) { + if (PTR_ERR(ddata->ref) != -EPROBE_DEFER) + dev_err(dev, "Failed to get vref regulator: %pe\n", + ddata->ref); + + return PTR_ERR(ddata->ref); + } + + ret = regulator_enable(ddata->ref); + if (ret < 0) { + dev_err(dev, "Failed to enable vref regulator: %pe\n", + ERR_PTR(ret)); + return ret; + } + + if (dev->platform_data) { + struct iio_map *plat_data; + + plat_data = (struct iio_map *)dev->platform_data; + + ret = iio_map_array_register(indio_dev, plat_data); + if (ret) { + dev_err(&indio_dev->dev, "iio map err: %d\n", ret); + goto err_regulator_disable; + } + } + + ddata->addr_prev = LTC2497_CONFIG_DEFAULT; + ddata->time_prev = ktime_get(); + + ret = iio_device_register(indio_dev); + if (ret < 0) + goto err_array_unregister; + + return 0; + +err_array_unregister: + iio_map_array_unregister(indio_dev); + +err_regulator_disable: + regulator_disable(ddata->ref); + + return ret; +} +EXPORT_SYMBOL_NS(ltc2497core_probe, LTC2497); + +void ltc2497core_remove(struct iio_dev *indio_dev) +{ + struct ltc2497core_driverdata *ddata = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + + iio_map_array_unregister(indio_dev); + + regulator_disable(ddata->ref); +} +EXPORT_SYMBOL_NS(ltc2497core_remove, LTC2497); + +MODULE_DESCRIPTION("common code for LTC2496/LTC2497 drivers"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/iio/adc/ltc2497.c b/drivers/iio/adc/ltc2497.c index 470406032720..5db63d7c6bc5 100644 --- a/drivers/iio/adc/ltc2497.c +++ b/drivers/iio/adc/ltc2497.c @@ -7,27 +7,18 @@ * Datasheet: http://cds.linear.com/docs/en/datasheet/2497fd.pdf */ -#include <linux/delay.h> #include <linux/i2c.h> #include <linux/iio/iio.h> #include <linux/iio/driver.h> -#include <linux/iio/sysfs.h> #include <linux/module.h> #include <linux/of.h> -#include <linux/regulator/consumer.h> -#define LTC2497_ENABLE 0xA0 -#define LTC2497_SGL BIT(4) -#define LTC2497_DIFF 0 -#define LTC2497_SIGN BIT(3) -#define LTC2497_CONFIG_DEFAULT LTC2497_ENABLE -#define LTC2497_CONVERSION_TIME_MS 150ULL +#include "ltc2497.h" -struct ltc2497_st { +struct ltc2497_driverdata { + /* this must be the first member */ + struct ltc2497core_driverdata common_ddata; struct i2c_client *client; - struct regulator *ref; - ktime_t time_prev; - u8 addr_prev; /* * DMA (thus cache coherency maintenance) requires the * transfer buffers to live in their own cache lines. @@ -35,232 +26,59 @@ struct ltc2497_st { __be32 buf ____cacheline_aligned; }; -static int ltc2497_wait_conv(struct ltc2497_st *st) +static int ltc2497_result_and_measure(struct ltc2497core_driverdata *ddata, + u8 address, int *val) { - s64 time_elapsed; - - time_elapsed = ktime_ms_delta(ktime_get(), st->time_prev); - - if (time_elapsed < LTC2497_CONVERSION_TIME_MS) { - /* delay if conversion time not passed - * since last read or write - */ - if (msleep_interruptible( - LTC2497_CONVERSION_TIME_MS - time_elapsed)) - return -ERESTARTSYS; - - return 0; - } - - if (time_elapsed - LTC2497_CONVERSION_TIME_MS <= 0) { - /* We're in automatic mode - - * so the last reading is stil not outdated - */ - return 0; - } - - return 1; -} - -static int ltc2497_read(struct ltc2497_st *st, u8 address, int *val) -{ - struct i2c_client *client = st->client; - int ret; - - ret = ltc2497_wait_conv(st); - if (ret < 0) - return ret; - - if (ret || st->addr_prev != address) { - ret = i2c_smbus_write_byte(st->client, - LTC2497_ENABLE | address); - if (ret < 0) - return ret; - st->addr_prev = address; - if (msleep_interruptible(LTC2497_CONVERSION_TIME_MS)) - return -ERESTARTSYS; - } - ret = i2c_master_recv(client, (char *)&st->buf, 3); - if (ret < 0) { - dev_err(&client->dev, "i2c_master_recv failed\n"); - return ret; - } - st->time_prev = ktime_get(); - - /* convert and shift the result, - * and finally convert from offset binary to signed integer - */ - *val = (be32_to_cpu(st->buf) >> 14) - (1 << 17); - - return ret; -} - -static int ltc2497_read_raw(struct iio_dev *indio_dev, - struct iio_chan_spec const *chan, - int *val, int *val2, long mask) -{ - struct ltc2497_st *st = iio_priv(indio_dev); + struct ltc2497_driverdata *st = + container_of(ddata, struct ltc2497_driverdata, common_ddata); int ret; - switch (mask) { - case IIO_CHAN_INFO_RAW: - mutex_lock(&indio_dev->mlock); - ret = ltc2497_read(st, chan->address, val); - mutex_unlock(&indio_dev->mlock); - if (ret < 0) - return ret; - - return IIO_VAL_INT; - - case IIO_CHAN_INFO_SCALE: - ret = regulator_get_voltage(st->ref); - if (ret < 0) + if (val) { + ret = i2c_master_recv(st->client, (char *)&st->buf, 3); + if (ret < 0) { + dev_err(&st->client->dev, "i2c_master_recv failed\n"); return ret; + } - *val = ret / 1000; - *val2 = 17; - - return IIO_VAL_FRACTIONAL_LOG2; - - default: - return -EINVAL; + *val = (be32_to_cpu(st->buf) >> 14) - (1 << 17); } -} -#define LTC2497_CHAN(_chan, _addr, _ds_name) { \ - .type = IIO_VOLTAGE, \ - .indexed = 1, \ - .channel = (_chan), \ - .address = (_addr | (_chan / 2) | ((_chan & 1) ? LTC2497_SIGN : 0)), \ - .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ - .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ - .datasheet_name = (_ds_name), \ -} - -#define LTC2497_CHAN_DIFF(_chan, _addr) { \ - .type = IIO_VOLTAGE, \ - .indexed = 1, \ - .channel = (_chan) * 2 + ((_addr) & LTC2497_SIGN ? 1 : 0), \ - .channel2 = (_chan) * 2 + ((_addr) & LTC2497_SIGN ? 0 : 1),\ - .address = (_addr | _chan), \ - .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ - .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ - .differential = 1, \ + ret = i2c_smbus_write_byte(st->client, + LTC2497_ENABLE | address); + if (ret) + dev_err(&st->client->dev, "i2c transfer failed: %pe\n", + ERR_PTR(ret)); + return ret; } -static const struct iio_chan_spec ltc2497_channel[] = { - LTC2497_CHAN(0, LTC2497_SGL, "CH0"), - LTC2497_CHAN(1, LTC2497_SGL, "CH1"), - LTC2497_CHAN(2, LTC2497_SGL, "CH2"), - LTC2497_CHAN(3, LTC2497_SGL, "CH3"), - LTC2497_CHAN(4, LTC2497_SGL, "CH4"), - LTC2497_CHAN(5, LTC2497_SGL, "CH5"), - LTC2497_CHAN(6, LTC2497_SGL, "CH6"), - LTC2497_CHAN(7, LTC2497_SGL, "CH7"), - LTC2497_CHAN(8, LTC2497_SGL, "CH8"), - LTC2497_CHAN(9, LTC2497_SGL, "CH9"), - LTC2497_CHAN(10, LTC2497_SGL, "CH10"), - LTC2497_CHAN(11, LTC2497_SGL, "CH11"), - LTC2497_CHAN(12, LTC2497_SGL, "CH12"), - LTC2497_CHAN(13, LTC2497_SGL, "CH13"), - LTC2497_CHAN(14, LTC2497_SGL, "CH14"), - LTC2497_CHAN(15, LTC2497_SGL, "CH15"), - LTC2497_CHAN_DIFF(0, LTC2497_DIFF), - LTC2497_CHAN_DIFF(1, LTC2497_DIFF), - LTC2497_CHAN_DIFF(2, LTC2497_DIFF), - LTC2497_CHAN_DIFF(3, LTC2497_DIFF), - LTC2497_CHAN_DIFF(4, LTC2497_DIFF), - LTC2497_CHAN_DIFF(5, LTC2497_DIFF), - LTC2497_CHAN_DIFF(6, LTC2497_DIFF), - LTC2497_CHAN_DIFF(7, LTC2497_DIFF), - LTC2497_CHAN_DIFF(0, LTC2497_DIFF | LTC2497_SIGN), - LTC2497_CHAN_DIFF(1, LTC2497_DIFF | LTC2497_SIGN), - LTC2497_CHAN_DIFF(2, LTC2497_DIFF | LTC2497_SIGN), - LTC2497_CHAN_DIFF(3, LTC2497_DIFF | LTC2497_SIGN), - LTC2497_CHAN_DIFF(4, LTC2497_DIFF | LTC2497_SIGN), - LTC2497_CHAN_DIFF(5, LTC2497_DIFF | LTC2497_SIGN), - LTC2497_CHAN_DIFF(6, LTC2497_DIFF | LTC2497_SIGN), - LTC2497_CHAN_DIFF(7, LTC2497_DIFF | LTC2497_SIGN), -}; - -static const struct iio_info ltc2497_info = { - .read_raw = ltc2497_read_raw, -}; - static int ltc2497_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct iio_dev *indio_dev; - struct ltc2497_st *st; - struct iio_map *plat_data; - int ret; + struct ltc2497_driverdata *st; + struct device *dev = &client->dev; if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C | I2C_FUNC_SMBUS_WRITE_BYTE)) return -EOPNOTSUPP; - indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st)); + indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); if (!indio_dev) return -ENOMEM; st = iio_priv(indio_dev); i2c_set_clientdata(client, indio_dev); st->client = client; + st->common_ddata.result_and_measure = ltc2497_result_and_measure; - indio_dev->dev.parent = &client->dev; - indio_dev->name = id->name; - indio_dev->info = <c2497_info; - indio_dev->modes = INDIO_DIRECT_MODE; - indio_dev->channels = ltc2497_channel; - indio_dev->num_channels = ARRAY_SIZE(ltc2497_channel); - - st->ref = devm_regulator_get(&client->dev, "vref"); - if (IS_ERR(st->ref)) - return PTR_ERR(st->ref); - - ret = regulator_enable(st->ref); - if (ret < 0) - return ret; - - if (client->dev.platform_data) { - plat_data = ((struct iio_map *)client->dev.platform_data); - ret = iio_map_array_register(indio_dev, plat_data); - if (ret) { - dev_err(&indio_dev->dev, "iio map err: %d\n", ret); - goto err_regulator_disable; - } - } - - ret = i2c_smbus_write_byte(st->client, LTC2497_CONFIG_DEFAULT); - if (ret < 0) - goto err_array_unregister; - - st->addr_prev = LTC2497_CONFIG_DEFAULT; - st->time_prev = ktime_get(); - - ret = iio_device_register(indio_dev); - if (ret < 0) - goto err_array_unregister; - - return 0; - -err_array_unregister: - iio_map_array_unregister(indio_dev); - -err_regulator_disable: - regulator_disable(st->ref); - - return ret; + return ltc2497core_probe(dev, indio_dev); } static int ltc2497_remove(struct i2c_client *client) { struct iio_dev *indio_dev = i2c_get_clientdata(client); - struct ltc2497_st *st = iio_priv(indio_dev); - iio_map_array_unregister(indio_dev); - iio_device_unregister(indio_dev); - regulator_disable(st->ref); + ltc2497core_remove(indio_dev); return 0; } diff --git a/drivers/iio/adc/ltc2497.h b/drivers/iio/adc/ltc2497.h new file mode 100644 index 000000000000..d0b42dd6b8ad --- /dev/null +++ b/drivers/iio/adc/ltc2497.h @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#define LTC2497_ENABLE 0xA0 +#define LTC2497_CONFIG_DEFAULT LTC2497_ENABLE +#define LTC2497_CONVERSION_TIME_MS 150ULL + +struct ltc2497core_driverdata { + struct regulator *ref; + ktime_t time_prev; + u8 addr_prev; + int (*result_and_measure)(struct ltc2497core_driverdata *ddata, + u8 address, int *val); +}; + +int ltc2497core_probe(struct device *dev, struct iio_dev *indio_dev); +void ltc2497core_remove(struct iio_dev *indio_dev); + +MODULE_IMPORT_NS(LTC2497); |