From: Jonathan Cameron <jic23@kernel.org>
To: Ludovic Tancerel <ludovic.tancerel@maplehightech.com>,
knaack.h@gmx.de, lars@metafoo.de, pmeerw@pmeerw.net,
linux-iio@vger.kernel.org, William.Markezana@meas-spec.com
Subject: Re: [PATCH V2 1/6] iio: Add meas-spec sensors common part
Date: Sat, 8 Aug 2015 17:58:04 +0100 [thread overview]
Message-ID: <55C6351C.7090404@kernel.org> (raw)
In-Reply-To: <1438248345-25820-2-git-send-email-ludovic.tancerel@maplehightech.com>
On 30/07/15 10:25, Ludovic Tancerel wrote:
> Signed-off-by: Ludovic Tancerel <ludovic.tancerel@maplehightech.com>
A few bits inline.
Also, would prefer some basic description of the patch up here...
> ---
> drivers/iio/common/Kconfig | 1 +
> drivers/iio/common/Makefile | 1 +
> drivers/iio/common/ms_sensors/Kconfig | 6 +
> drivers/iio/common/ms_sensors/Makefile | 5 +
> drivers/iio/common/ms_sensors/ms_sensors_i2c.c | 634 +++++++++++++++++++++++++
> drivers/iio/common/ms_sensors/ms_sensors_i2c.h | 54 +++
> 6 files changed, 701 insertions(+)
> create mode 100644 drivers/iio/common/ms_sensors/Kconfig
> create mode 100644 drivers/iio/common/ms_sensors/Makefile
> create mode 100644 drivers/iio/common/ms_sensors/ms_sensors_i2c.c
> create mode 100644 drivers/iio/common/ms_sensors/ms_sensors_i2c.h
>
> diff --git a/drivers/iio/common/Kconfig b/drivers/iio/common/Kconfig
> index 790f106..26a6026 100644
> --- a/drivers/iio/common/Kconfig
> +++ b/drivers/iio/common/Kconfig
> @@ -3,5 +3,6 @@
> #
>
> source "drivers/iio/common/hid-sensors/Kconfig"
> +source "drivers/iio/common/ms_sensors/Kconfig"
> source "drivers/iio/common/ssp_sensors/Kconfig"
> source "drivers/iio/common/st_sensors/Kconfig"
> diff --git a/drivers/iio/common/Makefile b/drivers/iio/common/Makefile
> index b1e4d9c..585da6a 100644
> --- a/drivers/iio/common/Makefile
> +++ b/drivers/iio/common/Makefile
> @@ -8,5 +8,6 @@
>
> # When adding new entries keep the list in alphabetical order
> obj-y += hid-sensors/
> +obj-y += ms_sensors/
> obj-y += ssp_sensors/
> obj-y += st_sensors/
> diff --git a/drivers/iio/common/ms_sensors/Kconfig b/drivers/iio/common/ms_sensors/Kconfig
> new file mode 100644
> index 0000000..b28a92b
> --- /dev/null
> +++ b/drivers/iio/common/ms_sensors/Kconfig
> @@ -0,0 +1,6 @@
> +#
> +# Measurements Specialties sensors common library
> +#
> +
> +config IIO_MS_SENSORS_I2C
> + tristate
> diff --git a/drivers/iio/common/ms_sensors/Makefile b/drivers/iio/common/ms_sensors/Makefile
> new file mode 100644
> index 0000000..7846428
> --- /dev/null
> +++ b/drivers/iio/common/ms_sensors/Makefile
> @@ -0,0 +1,5 @@
> +#
> +# Makefile for the Measurement Specialties sensor common modules.
> +#
> +
> +obj-$(CONFIG_IIO_MS_SENSORS_I2C) += ms_sensors_i2c.o
> diff --git a/drivers/iio/common/ms_sensors/ms_sensors_i2c.c b/drivers/iio/common/ms_sensors/ms_sensors_i2c.c
> new file mode 100644
> index 0000000..f5d27b6
> --- /dev/null
> +++ b/drivers/iio/common/ms_sensors/ms_sensors_i2c.c
> @@ -0,0 +1,634 @@
> +/*
> + * Measurements Specialties driver common i2c functions
> + *
> + * Copyright (c) 2015 Measurement-Specialties
> + *
> + * Licensed under the GPL-2.
> + *
> + */
> +
> +#include <linux/module.h>
> +#include <linux/iio/iio.h>
> +#include <linux/device.h>
> +#include <linux/delay.h>
> +
> +#include "ms_sensors_i2c.h"
> +
> +/* Conversion times in us */
> +static const u16 ms_sensors_ht_t_conversion_time[] = { 50000, 25000,
> + 13000, 7000 };
> +static const u16 ms_sensors_ht_h_conversion_time[] = { 16000, 3000,
> + 5000, 8000 };
> +static const u16 ms_sensors_tp_conversion_time[] = { 500, 1100, 2100,
> + 4100, 8220, 16440 };
> +
> +#define MS_SENSORS_SERIAL_READ_MSB 0xFA0F
> +#define MS_SENSORS_SERIAL_READ_LSB 0xFCC9
> +#define MS_SENSORS_USER_REG_WRITE 0xE6
> +#define MS_SENSORS_USER_REG_READ 0xE7
> +#define MS_SENSORS_HT_T_CONVERSION_START 0xF3
> +#define MS_SENSORS_HT_H_CONVERSION_START 0xF5
> +
> +#define MS_SENSORS_TP_PROM_READ 0xA0
> +#define MS_SENSORS_TP_T_CONVERSION_START 0x50
> +#define MS_SENSORS_TP_P_CONVERSION_START 0x40
> +#define MS_SENSORS_TP_ADC_READ 0x00
> +
> +#define MS_SENSORS_NO_READ_CMD 0xFF
> +
> +/**
> + * ms_sensors_i2c_reset() - i2c reset function
> + * @cli: pointer on i2c client
> + * @cmd: reset cmd. Depends on device in use
> + * @delay: usleep minimal delay after reset command is issued
> + *
> + * Generic I2C reset function for Measurement Specialties devices
> + *
> + * Return: 0 on success, negative errno otherwise.
> + */
> +int ms_sensors_i2c_reset(void *cli, u8 cmd, unsigned int delay)
> +{
> + int ret;
> + struct i2c_client *client = cli;
> +
> + ret = i2c_smbus_write_byte(client, cmd);
> + if (ret) {
> + dev_err(&client->dev, "Failed to reset device\n");
> + return ret;
> + }
> + usleep_range(delay, delay + 1000);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(ms_sensors_i2c_reset);
> +
> +/**
> + * ms_sensors_i2c_read_prom_word() - i2c prom word read function
> + * @cli: pointer on i2c client
> + * @cmd: PROM read cmd. Depends on device and prom id
> + * @word: pointer on word destination value
> + *
> + * Generic i2c prom word read function for Measurement Specialties devices
> + *
> + * Return: 0 on success, negative errno otherwise.
> + */
> +int ms_sensors_i2c_read_prom_word(void *cli, int cmd, u16 *word)
> +{
> + int ret;
> + struct i2c_client *client = (struct i2c_client *)cli;
> +
> + ret = i2c_smbus_read_word_swapped(client, cmd);
> + if (ret < 0) {
> + dev_err(&client->dev, "Failed to read prom word\n");
> + return ret;
> + }
> + *word = ret;
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(ms_sensors_i2c_read_prom_word);
> +
> +/**
> + * ms_sensors_i2c_convert_and_read() - i2c ADC conversion & read function
> + * @cli: pointer on i2c client
> + * @conv: ADC conversion command. Depends on device in use
> + * @rd: ADC read command. Depends on device in use
> + * @delay: usleep minimal delay after conversion command is issued
> + * @adc: pointer on ADC destination value
> + *
> + * Generic i2c ADC conversion & read function for Measurement Specialties
> + * devices.
> + * The function will issue conversion command, sleep appopriate delay, and
> + * issue command to read ADC
> + *
> + * Return: 0 on success, negative errno otherwise.
> + */
> +int ms_sensors_i2c_convert_and_read(void *cli, u8 conv, u8 rd,
> + unsigned int delay, u32 *adc)
> +{
> + int ret;
> + u32 buf = 0;
> + struct i2c_client *client = (struct i2c_client *)cli;
> +
> + /* Trigger conversion */
> + ret = i2c_smbus_write_byte(client, conv);
> + if (ret)
> + goto err;
> + usleep_range(delay, delay + 1000);
> +
> + /* Retrieve ADC value */
> + if (rd != MS_SENSORS_NO_READ_CMD)
> + ret = i2c_smbus_read_i2c_block_data(client, rd, 3, (u8 *)&buf);
> + else
> + ret = i2c_master_recv(client, (u8 *)&buf, 3);
> + if (ret < 0)
> + goto err;
> +
> + dev_dbg(&client->dev, "ADC raw value : %x\n", be32_to_cpu(buf) >> 8);
> + *adc = be32_to_cpu(buf) >> 8;
> +
> + return 0;
> +err:
> + dev_err(&client->dev, "Unable to make sensor adc conversion\n");
> + return ret;
> +}
> +EXPORT_SYMBOL(ms_sensors_i2c_convert_and_read);
> +
> +/**
> + * ms_sensors_crc_valid() - CRC check function
> + * @value: input and CRC compare value
> + *
> + * Cyclic Redundancy Check function used in TSYS02D, HTU21, MS8607.
> + * This function performs a x^8 + x^5 + x^4 + 1 polynomial CRC.
> + * The argument contains CRC value in LSB byte while the bytes 1 and 2
> + * are used for CRC computation
> + *
> + * Return: 1 if CRC is valid, 0 otherwise.
> + */
> +static bool ms_sensors_crc_valid(u32 value)
> +{
> + u32 polynom = 0x988000; /* x^8 + x^5 + x^4 + 1 */
> + u32 msb = 0x800000;
> + u32 mask = 0xFF8000;
> + u32 result = value & 0xFFFF00;
> + u8 crc = value & 0xFF;
> +
> + while (msb != 0x80) {
> + if (result & msb)
> + result = ((result ^ polynom) & mask)
> + | (result & ~mask);
> + msb >>= 1;
> + mask >>= 1;
> + polynom >>= 1;
> + }
> +
> + return result == crc;
> +}
> +
> +/**
> + * ms_sensors_i2c_read_serial() - i2c serial number read function
> + * @cli: pointer on i2c client
> + * @sn: pointer on 64-bits destination value
> + *
> + * Generic i2c serial number read function for Measurement Specialties devices.
> + * This function is used for TSYS02d, HTU21, MS8607 chipset.
> + * Refer to datasheet:
> + * http://www.meas-spec.com/downloads/HTU2X_Serial_Number_Reading.pdf
> + *
> + * Return: 0 on success, negative errno otherwise.
> + */
> +int ms_sensors_i2c_read_serial(struct i2c_client *client, u64 *sn)
> +{
> + u8 i;
> + u64 rcv_buf = 0;
> + u16 send_buf;
> + int ret;
> +
> + struct i2c_msg msg[2] = {
> + {
> + .addr = client->addr,
> + .flags = client->flags,
> + .len = 2,
> + .buf = (char *)&send_buf,
If you are going to type cast, please match the (__u8 *) from
include/uapi/linux/i2c.h
> + },
> + {
> + .addr = client->addr,
> + .flags = client->flags | I2C_M_RD,
> + .buf = (char *)&rcv_buf,
> + },
> + };
> +
> + /* Read MSB part of serial number */
> + send_buf = cpu_to_be16(MS_SENSORS_SERIAL_READ_MSB);
> + msg[1].len = 8;
> + ret = i2c_transfer(client->adapter, msg, 2);
> + if (ret < 0)
> + goto err;
> +
> + rcv_buf = be64_to_cpu(rcv_buf);
> + dev_dbg(&client->dev, "Serial MSB raw : %llx\n", rcv_buf);
> +
> + for (i = 0; i < 64; i += 16) {
> + if (!ms_sensors_crc_valid((rcv_buf >> i) & 0xFFFF))
> + return -ENODEV;
> + }
> +
> + *sn = (((rcv_buf >> 32) & 0xFF000000) |
> + ((rcv_buf >> 24) & 0x00FF0000) |
> + ((rcv_buf >> 16) & 0x0000FF00) |
> + ((rcv_buf >> 8) & 0x000000FF)) << 16;
> +
> + /* Read LSB part of serial number */
> + send_buf = cpu_to_be16(MS_SENSORS_SERIAL_READ_LSB);
> + msg[1].len = 6;
> + rcv_buf = 0;
> + ret = i2c_transfer(client->adapter, msg, 2);
> + if (ret < 0)
> + goto err;
> +
> + rcv_buf = be64_to_cpu(rcv_buf) >> 16;
> + dev_dbg(&client->dev, "Serial MSB raw : %llx\n", rcv_buf);
> +
> + for (i = 0; i < 48; i += 24) {
> + if (!ms_sensors_crc_valid((rcv_buf >> i) & 0xFFFFFF))
> + return -ENODEV;
> + }
> +
> + *sn |= (rcv_buf & 0xFFFF00) << 40 | (rcv_buf >> 32);
> +
> + return 0;
> +
> +err:
Put this inline and drop the goto
> + dev_err(&client->dev, "Unable to read device serial number");
> + return ret;
> +}
> +EXPORT_SYMBOL(ms_sensors_i2c_read_serial);
> +
What is meant by a user_reg as opposed to other regs?
> +static int ms_sensors_i2c_read_user_reg(struct i2c_client *client,
> + u8 *user_reg)
> +{
> + int ret;
> +
> + ret = i2c_smbus_write_byte(client, MS_SENSORS_USER_REG_READ);
> + if (ret)
> + goto err;
> +
> + ret = i2c_master_recv(client, user_reg, 1);
> + if (ret < 0)
> + goto err;
> + dev_dbg(&client->dev, "User register :%x\n", *user_reg);
> +
> + return 0;
> +err:
> + dev_err(&client->dev, "Unable to read user reg");
> + return ret;
> +}
> +
> +/**
> + * ms_sensors_i2c_write_resolution() - set resolution i2c function
> + * @dev_data: pointer on temperature/humidity device data
> + * @i: resolution index to set
> + *
> + * That function will program the appropriate resolution based on the index
> + * provided when user space will set samp_freq channel.
> + * That function is used for TSYS02D, HTU21 and MS8607 chipsets
> + *
> + * Return: 0 on success, negative errno otherwise.
> + */
> +ssize_t ms_sensors_i2c_write_resolution(struct ms_ht_dev *dev_data,
> + u8 i)
> +{
> + u8 user_reg;
> + int ret;
> +
> + ret = ms_sensors_i2c_read_user_reg(dev_data->client, &user_reg);
> + if (ret)
> + return ret;
> +
> + user_reg &= 0x7E;
> + user_reg |= ((i & 1) << 7) + ((i & 2) >> 1);
> +
> + return i2c_smbus_write_byte_data(dev_data->client,
> + MS_SENSORS_USER_REG_WRITE,
> + user_reg);
> +}
> +EXPORT_SYMBOL(ms_sensors_i2c_write_resolution);
> +
> +/**
> + * ms_sensors_i2c_show_battery_low() - show device battery low indicator
> + * @dev_data: pointer on temperature/humidity device data
> + * @buf: pointer on char buffer to write result
> + *
> + * That function will read battery indicator value in the device and
> + * return 1 if the device voltage is below 2.25V.
> + * That function is used for TSYS02D, HTU21 and MS8607 chipsets
> + *
> + * Return: length of sprintf on success, negative errno otherwise.
> + */
> +ssize_t ms_sensors_i2c_show_battery_low(struct ms_ht_dev *dev_data,
> + char *buf)
> +{
> + int ret;
> + u8 user_reg;
> +
> + mutex_lock(&dev_data->lock);
> + ret = ms_sensors_i2c_read_user_reg(dev_data->client, &user_reg);
> + mutex_unlock(&dev_data->lock);
> + if (ret)
> + return ret;
> +
> + return sprintf(buf, "%d\n", (user_reg & 0x40) >> 6);
> +}
> +EXPORT_SYMBOL(ms_sensors_i2c_show_battery_low);
> +
> +/**
> + * ms_sensors_i2c_show_heater() - show device heater
> + * @dev_data: pointer on temperature/humidity device data
> + * @buf: pointer on char buffer to write result
> + *
> + * That function will read heater enable value in the device and
> + * return 1 if the heater is enabled
> + * That function is used for HTU21 and MS8607 chipsets
> + *
> + * Return: length of sprintf on success, negative errno otherwise.
> + */
> +ssize_t ms_sensors_i2c_show_heater(struct ms_ht_dev *dev_data,
> + char *buf)
> +{
> + u8 user_reg;
> + int ret;
> +
> + mutex_lock(&dev_data->lock);
> + ret = ms_sensors_i2c_read_user_reg(dev_data->client, &user_reg);
> + mutex_unlock(&dev_data->lock);
> + if (ret)
> + return ret;
> +
> + return sprintf(buf, "%d\n", (user_reg & 0x4) >> 2);
> +}
> +EXPORT_SYMBOL(ms_sensors_i2c_show_heater);
> +
> +/**
> + * ms_sensors_i2c_write_heater() - write device heater
I'm not sure the _i2c_ bit is important in this function name...
> + * @dev_data: pointer on temperature/humidity device data
> + * @buf: pointer on char buffer from user space
> + * @len: length of buf
> + *
> + * That function will write 1 or 0 value in the device
> + * to enable or disable heater
> + * That function is used for HTU21 and MS8607 chipsets
That->This
> + *
> + * Return: length of buffer, negative errno otherwise.
> + */
> +ssize_t ms_sensors_i2c_write_heater(struct ms_ht_dev *dev_data,
> + const char *buf, size_t len)
> +{
> + u8 val, user_reg;
> + int ret;
> +
> + ret = kstrtou8(buf, 10, &val);
> + if (ret)
> + return ret;
> +
> + if (val > 1)
> + return -EINVAL;
> +
> + mutex_lock(&dev_data->lock);
> + ret = ms_sensors_i2c_read_user_reg(dev_data->client, &user_reg);
> + if (ret) {
> + mutex_unlock(&dev_data->lock);
> + return ret;
> + }
> +
> + user_reg &= 0xFB;
> + user_reg |= val << 2;
> +
> + ret = i2c_smbus_write_byte_data(dev_data->client,
> + MS_SENSORS_USER_REG_WRITE,
> + user_reg);
> + mutex_unlock(&dev_data->lock);
> + if (ret) {
> + dev_err(&dev_data->client->dev, "Unable to write user reg\n");
> + return ret;
> + }
> +
> + return len;
> +}
> +EXPORT_SYMBOL(ms_sensors_i2c_write_heater);
> +
> +/**
> + * ms_sensors_i2c_ht_read_temperature() - i2c read temperature
> + * @dev_data: pointer on temperature/humidity device data
> + * @temperature:pointer on temperature destination value
> + *
> + * That function will get temperature ADC value from the device,
> + * check the CRC and compute the temperature value.
> + * That function is used for TSYS02D, HTU21 and MS8607 chipsets
> + *
> + * Return: 0 on success, negative errno otherwise.
> + */
> +int ms_sensors_i2c_ht_read_temperature(struct ms_ht_dev *dev_data,
> + s32 *temperature)
> +{
> + int ret;
> + u32 adc;
> + u16 delay;
> +
> + mutex_lock(&dev_data->lock);
> + delay = ms_sensors_ht_t_conversion_time[dev_data->res_index];
> + ret = ms_sensors_i2c_convert_and_read(dev_data->client,
> + MS_SENSORS_HT_T_CONVERSION_START,
> + MS_SENSORS_NO_READ_CMD,
> + delay, &adc);
> + mutex_unlock(&dev_data->lock);
> + if (ret)
> + return ret;
> +
> + if (!ms_sensors_crc_valid(adc)) {
> + dev_err(&dev_data->client->dev,
> + "Temperature read crc check error\n");
> + return -ENODEV;
> + }
> +
> + /* Temperature algorithm */
> + *temperature = (((s64)(adc >> 8) * 175720) >> 16) - 46850;
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(ms_sensors_i2c_ht_read_temperature);
> +
> +/**
> + * ms_sensors_i2c_ht_read_humidity() - i2c read humidity
> + * @dev_data: pointer on temperature/humidity device data
> + * @humidity: pointer on humidity destination value
> + *
> + * That function will get humidity ADC value from the device,
> + * check the CRC and compute the temperature value.
> + * That function is used for HTU21 and MS8607 chipsets
> + *
> + * Return: 0 on success, negative errno otherwise.
> + */
> +int ms_sensors_i2c_ht_read_humidity(struct ms_ht_dev *dev_data,
> + u32 *humidity)
> +{
> + int ret;
> + u32 adc;
> + u16 delay;
> +
> + mutex_lock(&dev_data->lock);
> + delay = ms_sensors_ht_h_conversion_time[dev_data->res_index];
> + ret = ms_sensors_i2c_convert_and_read(dev_data->client,
> + MS_SENSORS_HT_H_CONVERSION_START,
> + MS_SENSORS_NO_READ_CMD,
> + delay, &adc);
> + mutex_unlock(&dev_data->lock);
> + if (ret)
> + return ret;
> +
> + if (!ms_sensors_crc_valid(adc)) {
> + dev_err(&dev_data->client->dev,
> + "Humidity read crc check error\n");
> + return -ENODEV;
> + }
> +
> + /* Humidity algorithm */
> + *humidity = (((s32)(adc >> 8) * 12500) >> 16) * 10 - 6000;
> + if (*humidity >= 100000)
> + *humidity = 100000;
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(ms_sensors_i2c_ht_read_humidity);
> +
Multiline comment syntax is
/*
* CRC...
*/
Or ideally use kernel-doc as you have for other functions below
(not required as not exported)
> +/* CRC check function for Temperature and pressure devices
> + * That function is only used when reading PROM coefficients */
> +static bool ms_sensors_tp_crc_valid(u16 *prom, u8 len)
> +{
> + unsigned int cnt, n_bit;
> + u16 n_rem = 0x0000, crc_read = prom[0], crc = (*prom & 0xF000) >> 12;
> +
> + prom[len - 1] = 0;
> + prom[0] &= 0x0FFF; /* Clear the CRC computation part */
> +
> + for (cnt = 0; cnt < len * 2; cnt++) {
> + if (cnt % 2 == 1)
> + n_rem ^= prom[cnt >> 1] & 0x00FF;
> + else
> + n_rem ^= prom[cnt >> 1] >> 8;
> +
> + for (n_bit = 8; n_bit > 0; n_bit--) {
> + if (n_rem & 0x8000)
> + n_rem = (n_rem << 1) ^ 0x3000;
> + else
> + n_rem <<= 1;
> + }
> + }
> + n_rem >>= 12;
> + prom[0] = crc_read;
> +
> + return n_rem == crc;
> +}
> +
> +/**
> + * ms_sensors_tp_read_prom() - prom coeff read function
> + * @dev_data: pointer on temperature/pressure device data
pointer to temperature/... (fix throughout driver please)
> + *
> + * That function will read prom coefficients and check CRC
That -> This (and add a full stop at the end of the sentence.
> + * That function is used for MS5637 and MS8607 chipsets
> + *
> + * Return: 0 on success, negative errno otherwise.
> + */
> +int ms_sensors_tp_read_prom(struct ms_tp_dev *dev_data)
> +{
> + int i, ret;
> +
> + for (i = 0; i < MS_SENSORS_TP_PROM_WORDS_NB; i++) {
> + ret = ms_sensors_i2c_read_prom_word(
> + dev_data->client,
> + MS_SENSORS_TP_PROM_READ + (i << 1),
> + &dev_data->prom[i]);
> +
> + if (ret)
> + return ret;
> + }
> +
> + if (!ms_sensors_tp_crc_valid(dev_data->prom,
> + MS_SENSORS_TP_PROM_WORDS_NB + 1)) {
> + dev_err(&dev_data->client->dev,
> + "Calibration coefficients crc check error\n");
> + return -ENODEV;
> + }
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(ms_sensors_tp_read_prom);
> +
> +/**
> + * ms_sensors_read_temp_and_pressure() - read temp and pressure
> + * @dev_data: pointer on temperature/pressure device data
pointer to
> + * @temperature:pointer on temperature destination value
pointer to (also missing tab?)
> + * @pressure: pointer on pressure destination value
> + *
> + * That function will read ADC and compute pressure and temperature value
That->This and full stop at end of sentence.
> + * That function is used for MS5637 and MS8607 chipsets
> + *
> + * Return: 0 on success, negative errno otherwise.
> + */
> +int ms_sensors_read_temp_and_pressure(struct ms_tp_dev *dev_data,
> + int *temperature,
> + unsigned int *pressure)
> +{
> + int ret;
> + u32 t_adc, p_adc;
> + s32 dt, temp;
> + s64 off, sens, t2, off2, sens2;
> + u16 *prom = dev_data->prom, delay;
> + u8 i;
> +
> + mutex_lock(&dev_data->lock);
> + i = dev_data->res_index * 2;
> + delay = ms_sensors_tp_conversion_time[dev_data->res_index];
Blank line here would improve readability.
> + ret = ms_sensors_i2c_convert_and_read(
> + dev_data->client,
> + MS_SENSORS_TP_T_CONVERSION_START + i,
> + MS_SENSORS_TP_ADC_READ,
> + delay, &t_adc);
> + if (ret) {
> + mutex_unlock(&dev_data->lock);
> + return ret;
> + }
blank line here.
> + ret = ms_sensors_i2c_convert_and_read(
> + dev_data->client,
> + MS_SENSORS_TP_P_CONVERSION_START + i,
> + MS_SENSORS_TP_ADC_READ,
> + delay, &p_adc);
> + mutex_unlock(&dev_data->lock);
> + if (ret)
> + return ret;
> +
> + dt = (s32)t_adc - (prom[5] << 8);
> +
> + /* Actual temperature = 2000 + dT * TEMPSENS */
> + temp = 2000 + (((s64)dt * prom[6]) >> 23);
> +
> + /* Second order temperature compensation */
> + if (temp < 2000) {
> + s64 tmp = (s64)temp - 2000;
> +
> + t2 = (3 * ((s64)dt * (s64)dt)) >> 33;
> + off2 = (61 * tmp * tmp) >> 4;
> + sens2 = (29 * tmp * tmp) >> 4;
> +
> + if (temp < -1500) {
> + s64 tmp = (s64)temp + 1500;
> +
> + off2 += 17 * tmp * tmp;
> + sens2 += 9 * tmp * tmp;
> + }
> + } else {
> + t2 = (5 * ((s64)dt * (s64)dt)) >> 38;
> + off2 = 0;
> + sens2 = 0;
> + }
> +
> + /* OFF = OFF_T1 + TCO * dT */
> + off = (((s64)prom[2]) << 17) + ((((s64)prom[4]) * (s64)dt) >> 6);
> + off -= off2;
> +
> + /* Sensitivity at actual temperature = SENS_T1 + TCS * dT */
> + sens = (((s64)prom[1]) << 16) + (((s64)prom[3] * dt) >> 7);
> + sens -= sens2;
> +
> + /* Temperature compensated pressure = D1 * SENS - OFF */
> + *temperature = (temp - t2) * 10;
> + *pressure = (u32)(((((s64)p_adc * sens) >> 21) - off) >> 15);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(ms_sensors_read_temp_and_pressure);
> +
> +MODULE_DESCRIPTION("Measurement-Specialties common i2c driver");
> +MODULE_AUTHOR("William Markezana <william.markezana@meas-spec.com>");
> +MODULE_AUTHOR("Ludovic Tancerel <ludovic.tancerel@maplehightech.com>");
> +MODULE_LICENSE("GPL v2");
> +
> diff --git a/drivers/iio/common/ms_sensors/ms_sensors_i2c.h b/drivers/iio/common/ms_sensors/ms_sensors_i2c.h
> new file mode 100644
> index 0000000..a521428
> --- /dev/null
> +++ b/drivers/iio/common/ms_sensors/ms_sensors_i2c.h
> @@ -0,0 +1,54 @@
> +/*
> + * Measurements Specialties common sensor driver
> + *
> + * Copyright (c) 2015 Measurement-Specialties
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
Unnecesary blank line here.
> + */
> +
> +#ifndef _MS_SENSORS_I2C_H
> +#define _MS_SENSORS_I2C_H
> +
> +#include <linux/i2c.h>
> +#include <linux/mutex.h>
> +
> +#define MS_SENSORS_TP_PROM_WORDS_NB 7
> +
> +struct ms_ht_dev {
> + struct i2c_client *client;
> + struct mutex lock; /* mutex protecting data structure */
> + u8 res_index;
> +};
> +
> +struct ms_tp_dev {
> + struct i2c_client *client;
> + struct mutex lock; /* mutex protecting data structure */
> + /* Added element for CRC computation */
> + u16 prom[MS_SENSORS_TP_PROM_WORDS_NB + 1];
> + u8 res_index;
> +};
> +
> +int ms_sensors_i2c_reset(void *cli, u8 cmd, unsigned int delay);
> +int ms_sensors_i2c_read_prom_word(void *cli, int cmd, u16 *word);
> +int ms_sensors_i2c_convert_and_read(void *cli, u8 conv, u8 rd,
> + unsigned int delay, u32 *adc);
> +int ms_sensors_i2c_read_serial(struct i2c_client *client, u64 *sn);
> +ssize_t ms_sensors_i2c_show_serial(struct ms_ht_dev *dev_data, char *buf);
> +ssize_t ms_sensors_i2c_write_resolution(struct ms_ht_dev *dev_data, u8 i);
> +ssize_t ms_sensors_i2c_show_battery_low(struct ms_ht_dev *dev_data, char *buf);
> +ssize_t ms_sensors_i2c_show_heater(struct ms_ht_dev *dev_data, char *buf);
> +ssize_t ms_sensors_i2c_write_heater(struct ms_ht_dev *dev_data,
> + const char *buf, size_t len);
> +int ms_sensors_i2c_ht_read_temperature(struct ms_ht_dev *dev_data,
> + s32 *temperature);
> +int ms_sensors_i2c_ht_read_humidity(struct ms_ht_dev *dev_data,
> + u32 *humidity);
> +int ms_sensors_tp_read_prom(struct ms_tp_dev *dev_data);
> +int ms_sensors_read_temp_and_pressure(struct ms_tp_dev *dev_data,
> + int *temperature,
> + unsigned int *pressure);
> +
> +#endif /* _MS_SENSORS_I2C_H */
>
next prev parent reply other threads:[~2015-08-08 16:58 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-30 9:25 [PATCH V2 0/6] iio: TSYS01, TSYS02D, HTU21, MS5637, MS8607 Measurement Specialties driver development Ludovic Tancerel
2015-07-30 9:25 ` [PATCH V2 1/6] iio: Add meas-spec sensors common part Ludovic Tancerel
2015-08-08 16:58 ` Jonathan Cameron [this message]
2015-08-10 7:43 ` Crt Mori
2015-08-10 11:07 ` Crt Mori
2015-08-15 20:09 ` Jonathan Cameron
2015-09-14 12:56 ` ludovic.tancerel
2015-09-20 19:22 ` Jonathan Cameron
2015-09-23 20:55 ` ludovic.tancerel
2015-07-30 9:25 ` [PATCH V2 2/6] iio: Add tsys01 meas-spec driver support Ludovic Tancerel
2015-08-08 17:03 ` Jonathan Cameron
2015-08-08 17:04 ` Jonathan Cameron
2015-07-30 9:25 ` [PATCH V2 3/6] iio: Add tsys02d " Ludovic Tancerel
2015-08-08 17:15 ` Jonathan Cameron
2015-08-09 12:33 ` Guenter Roeck
2015-08-09 20:13 ` Hartmut Knaack
2015-08-09 20:21 ` Guenter Roeck
2015-07-30 9:25 ` [PATCH V2 4/6] iio: Add htu21 " Ludovic Tancerel
2015-08-08 17:17 ` Jonathan Cameron
2015-07-30 9:25 ` [PATCH V2 5/6] iio: Add ms5637 " Ludovic Tancerel
2015-07-30 9:25 ` [PATCH V2 6/6] iio: Add ms8607 " Ludovic Tancerel
2015-08-08 17:22 ` Jonathan Cameron
2015-09-25 9:25 ` ludovic.tancerel
2015-09-25 9:31 ` ludovic.tancerel
2015-09-27 16:01 ` Jonathan Cameron
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