From: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
To: Peter Meerwald-Stadler <pmeerw@pmeerw.net>
Cc: Jonathan Cameron <jic23@kernel.org>,
linux-iio@vger.kernel.org,
Lorenzo BIANCONI <lorenzo.bianconi@st.com>
Subject: Re: [PATCH v2 1/2] iio: imu: add support to lsm6dsx driver
Date: Fri, 9 Dec 2016 19:29:52 +0100 [thread overview]
Message-ID: <CAA2SeNLNtaa5qiO=LoCNsrS+j4z1a+0sV03c34iC+t9Tw4HXKg@mail.gmail.com> (raw)
In-Reply-To: <alpine.DEB.2.02.1612061229090.29508@pmeerw.net>
Hi Peter,
Thanks for the review. I imported your comments (most of them in
common with Jonathan).
Regards,
Lorenzo
>> Add support to STM LSM6DS3-LSM6DSM 6-axis (acc + gyro) Mems sensor
>
> nitpicking below
>
>> http://www.st.com/resource/en/datasheet/lsm6ds3.pdf
>> http://www.st.com/resource/en/datasheet/lsm6dsm.pdf
>>
>> - continuous mode support
>> - i2c support
>> - spi support
>> - sw fifo mode support
>> - supported devices: lsm6ds3, lsm6dsm
>>
>> Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@st.com>
>> ---
>> drivers/iio/imu/Kconfig | 1 +
>> drivers/iio/imu/Makefile | 2 +
>> drivers/iio/imu/st_lsm6dsx/Kconfig | 23 +
>> drivers/iio/imu/st_lsm6dsx/Makefile | 6 +
>> drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h | 107 ++++
>> drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c | 696 +++++++++++++++++++++++++++
>> drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c | 111 +++++
>> drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_ring.c | 401 +++++++++++++++
>> drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_spi.c | 129 +++++
>> 9 files changed, 1476 insertions(+)
>> create mode 100644 drivers/iio/imu/st_lsm6dsx/Kconfig
>> create mode 100644 drivers/iio/imu/st_lsm6dsx/Makefile
>> create mode 100644 drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
>> create mode 100644 drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
>> create mode 100644 drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c
>> create mode 100644 drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_ring.c
>> create mode 100644 drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_spi.c
>>
>> diff --git a/drivers/iio/imu/Kconfig b/drivers/iio/imu/Kconfig
>> index 1f1ad41..156630a 100644
>> --- a/drivers/iio/imu/Kconfig
>> +++ b/drivers/iio/imu/Kconfig
>> @@ -39,6 +39,7 @@ config KMX61
>> be called kmx61.
>>
>> source "drivers/iio/imu/inv_mpu6050/Kconfig"
>> +source "drivers/iio/imu/st_lsm6dsx/Kconfig"
>>
>> endmenu
>>
>> diff --git a/drivers/iio/imu/Makefile b/drivers/iio/imu/Makefile
>> index c71bcd3..8b563c3 100644
>> --- a/drivers/iio/imu/Makefile
>> +++ b/drivers/iio/imu/Makefile
>> @@ -17,3 +17,5 @@ obj-y += bmi160/
>> obj-y += inv_mpu6050/
>>
>> obj-$(CONFIG_KMX61) += kmx61.o
>> +
>> +obj-y += st_lsm6dsx/
>> diff --git a/drivers/iio/imu/st_lsm6dsx/Kconfig b/drivers/iio/imu/st_lsm6dsx/Kconfig
>> new file mode 100644
>> index 0000000..9a0781b
>> --- /dev/null
>> +++ b/drivers/iio/imu/st_lsm6dsx/Kconfig
>> @@ -0,0 +1,23 @@
>> +
>> +config IIO_ST_LSM6DSX
>> + tristate "ST_LSM6DSx driver for STM 6-axis imu Mems sensors"
>
> IMU and MEMS are both abbreviations, consider consistent uppercasing
>
>> + depends on (I2C || SPI)
>> + select IIO_BUFFER
>> + select IIO_KFIFO_BUF
>> + select IIO_ST_LSM6DSX_I2C if (I2C)
>> + select IIO_ST_LSM6DSX_SPI if (SPI_MASTER)
>> + help
>> + Say yes here to build support for STMicroelectronics LSM6DSx imu
>> + sensor. Supported devices: lsm6ds3, lsm6dsm
>> +
>> + To compile this driver as a module, choose M here: the module
>> + will be called st_lsm6dsx.
>> +
>> +config IIO_ST_LSM6DSX_I2C
>> + tristate
>> + depends on IIO_ST_LSM6DSX
>> +
>> +config IIO_ST_LSM6DSX_SPI
>> + tristate
>> + depends on IIO_ST_LSM6DSX
>> +
>> diff --git a/drivers/iio/imu/st_lsm6dsx/Makefile b/drivers/iio/imu/st_lsm6dsx/Makefile
>> new file mode 100644
>> index 0000000..812d655
>> --- /dev/null
>> +++ b/drivers/iio/imu/st_lsm6dsx/Makefile
>> @@ -0,0 +1,6 @@
>> +st_lsm6dsx-y := st_lsm6dsx_core.o \
>> + st_lsm6dsx_ring.o
>> +
>> +obj-$(CONFIG_IIO_ST_LSM6DSX) += st_lsm6dsx.o
>> +obj-$(CONFIG_IIO_ST_LSM6DSX_I2C) += st_lsm6dsx_i2c.o
>> +obj-$(CONFIG_IIO_ST_LSM6DSX_SPI) += st_lsm6dsx_spi.o
>> diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
>> new file mode 100644
>> index 0000000..a43beab
>> --- /dev/null
>> +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
>> @@ -0,0 +1,107 @@
>> +/*
>> + * STMicroelectronics st_lsm6dsx sensor driver
>> + *
>> + * Copyright 2016 STMicroelectronics Inc.
>> + *
>> + * Lorenzo Bianconi <lorenzo.bianconi@st.com>
>> + * Denis Ciocca <denis.ciocca@st.com>
>> + *
>> + * Licensed under the GPL-2.
>> + */
>> +
>> +#ifndef ST_LSM6DSX_H
>> +#define ST_LSM6DSX_H
>> +
>> +#include <linux/device.h>
>> +
>> +#define ST_LSM6DS3_DEV_NAME "lsm6ds3"
>> +#define ST_LSM6DSM_DEV_NAME "lsm6dsm"
>> +
>> +#define ST_LSM6DSX_CHAN_SIZE 2
>> +#define ST_LSM6DSX_SAMPLE_SIZE 6
>> +#define ST_LSM6DSX_SAMPLE_DEPTH (ST_LSM6DSX_SAMPLE_SIZE / \
>> + ST_LSM6DSX_CHAN_SIZE)
>> +
>> +#if defined(CONFIG_SPI_MASTER)
>> +#define ST_LSM6DSX_RX_MAX_LENGTH 256
>> +#define ST_LSM6DSX_TX_MAX_LENGTH 8
>> +
>> +struct st_lsm6dsx_transfer_buffer {
>> + u8 rx_buf[ST_LSM6DSX_RX_MAX_LENGTH];
>> + u8 tx_buf[ST_LSM6DSX_TX_MAX_LENGTH] ____cacheline_aligned;
>> +};
>> +#endif /* CONFIG_SPI_MASTER */
>> +
>> +struct st_lsm6dsx_transfer_function {
>> + int (*read)(struct device *dev, u8 addr, int len, u8 *data);
>> + int (*write)(struct device *dev, u8 addr, int len, u8 *data);
>> +};
>> +
>> +struct st_lsm6dsx_reg {
>> + u8 addr;
>> + u8 mask;
>> +};
>> +
>> +struct st_lsm6dsx_settings {
>> + u8 wai;
>> + u16 max_fifo_size;
>> +};
>> +
>> +enum st_lsm6dsx_sensor_id {
>> + ST_LSM6DSX_ID_ACC,
>> + ST_LSM6DSX_ID_GYRO,
>> + ST_LSM6DSX_ID_MAX,
>> +};
>> +
>> +enum st_lsm6dsx_fifo_mode {
>> + ST_LSM6DSX_FIFO_BYPASS = 0x0,
>> + ST_LSM6DSX_FIFO_CONT = 0x6,
>> +};
>> +
>> +struct st_lsm6dsx_sensor {
>> + enum st_lsm6dsx_sensor_id id;
>> + struct st_lsm6dsx_hw *hw;
>> +
>> + u32 gain;
>> + u16 odr;
>> +
>> + u16 watermark;
>> + u8 sip;
>> + u8 decimator;
>> + u8 decimator_mask;
>> +
>> + s64 delta_ts;
>> + s64 ts;
>> +};
>> +
>> +struct st_lsm6dsx_hw {
>> + const char *name;
>> + struct device *dev;
>> + int irq;
>> + struct mutex lock;
>> +
>> + enum st_lsm6dsx_fifo_mode fifo_mode;
>> + u8 enable_mask;
>> + u8 sip;
>> +
>> + struct iio_dev *iio_devs[ST_LSM6DSX_ID_MAX];
>> +
>> + const struct st_lsm6dsx_settings *settings;
>> +
>> + const struct st_lsm6dsx_transfer_function *tf;
>> +#if defined(CONFIG_SPI_MASTER)
>> + struct st_lsm6dsx_transfer_buffer tb;
>> +#endif /* CONFIG_SPI_MASTER */
>> +};
>> +
>> +int st_lsm6dsx_probe(struct st_lsm6dsx_hw *hw);
>> +int st_lsm6dsx_sensor_enable(struct st_lsm6dsx_sensor *sensor);
>> +int st_lsm6dsx_sensor_disable(struct st_lsm6dsx_sensor *sensor);
>> +int st_lsm6dsx_allocate_rings(struct st_lsm6dsx_hw *hw);
>> +int st_lsm6dsx_write_with_mask(struct st_lsm6dsx_hw *hw, u8 addr, u8 mask,
>> + u8 val);
>> +int st_lsm6dsx_update_watermark(struct st_lsm6dsx_sensor *sensor,
>> + u16 watermark);
>> +
>> +#endif /* ST_LSM6DSX_H */
>> +
>> diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
>> new file mode 100644
>> index 0000000..ae4cf30
>> --- /dev/null
>> +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
>> @@ -0,0 +1,696 @@
>> +/*
>> + * STMicroelectronics st_lsm6dsx sensor driver
>> + *
>> + * Copyright 2016 STMicroelectronics Inc.
>> + *
>> + * Lorenzo Bianconi <lorenzo.bianconi@st.com>
>> + * Denis Ciocca <denis.ciocca@st.com>
>> + *
>> + * Licensed under the GPL-2.
>> + */
>> +
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/delay.h>
>> +#include <linux/iio/iio.h>
>> +#include <linux/iio/sysfs.h>
>> +#include <asm/unaligned.h>
>> +
>> +#include "st_lsm6dsx.h"
>> +
>> +#define ST_LSM6DSX_REG_ACC_DEC_MASK 0x07
>
> masks could be represented using GENMASK() or BIT()
>
>> +#define ST_LSM6DSX_REG_GYRO_DEC_MASK 0x38
>> +#define ST_LSM6DSX_REG_INT1_ADDR 0x0d
>> +#define ST_LSM6DSX_REG_FIFO_FTH_IRQ_MASK 0x08
>> +#define ST_LSM6DSX_REG_WHOAMI_ADDR 0x0f
>> +#define ST_LSM6DSX_REG_RESET_ADDR 0x12
>> +#define ST_LSM6DSX_REG_RESET_MASK 0x01
>> +#define ST_LSM6DSX_REG_BDU_ADDR 0x12
>> +#define ST_LSM6DSX_REG_BDU_MASK 0x40
>> +#define ST_LSM6DSX_REG_INT2_ON_INT1_ADDR 0x13
>> +#define ST_LSM6DSX_REG_INT2_ON_INT1_MASK 0x20
>> +#define ST_LSM6DSX_REG_ROUNDING_ADDR 0x16
>> +#define ST_LSM6DSX_REG_ROUNDING_MASK 0x04
>> +#define ST_LSM6DSX_REG_LIR_ADDR 0x58
>> +#define ST_LSM6DSX_REG_LIR_MASK 0x01
>> +
>> +#define ST_LSM6DSX_REG_ACC_ODR_ADDR 0x10
>> +#define ST_LSM6DSX_REG_ACC_ODR_MASK 0xf0
>> +#define ST_LSM6DSX_REG_ACC_FS_ADDR 0x10
>> +#define ST_LSM6DSX_REG_ACC_FS_MASK 0x0c
>> +#define ST_LSM6DSX_REG_ACC_OUT_X_L_ADDR 0x28
>> +#define ST_LSM6DSX_REG_ACC_OUT_Y_L_ADDR 0x2a
>> +#define ST_LSM6DSX_REG_ACC_OUT_Z_L_ADDR 0x2c
>> +
>> +#define ST_LSM6DSX_REG_GYRO_ODR_ADDR 0x11
>> +#define ST_LSM6DSX_REG_GYRO_ODR_MASK 0xf0
>> +#define ST_LSM6DSX_REG_GYRO_FS_ADDR 0x11
>> +#define ST_LSM6DSX_REG_GYRO_FS_MASK 0x0c
>> +#define ST_LSM6DSX_REG_GYRO_OUT_X_L_ADDR 0x22
>> +#define ST_LSM6DSX_REG_GYRO_OUT_Y_L_ADDR 0x24
>> +#define ST_LSM6DSX_REG_GYRO_OUT_Z_L_ADDR 0x26
>> +
>> +#define ST_LSM6DS3_WHOAMI 0x69
>> +#define ST_LSM6DSM_WHOAMI 0x6a
>> +
>> +#define ST_LSM6DS3_MAX_FIFO_SIZE 8192
>> +#define ST_LSM6DSM_MAX_FIFO_SIZE 4096
>> +
>> +#define ST_LSM6DSX_ACC_FS_2G_GAIN IIO_G_TO_M_S_2(61)
>> +#define ST_LSM6DSX_ACC_FS_4G_GAIN IIO_G_TO_M_S_2(122)
>> +#define ST_LSM6DSX_ACC_FS_8G_GAIN IIO_G_TO_M_S_2(244)
>> +#define ST_LSM6DSX_ACC_FS_16G_GAIN IIO_G_TO_M_S_2(488)
>> +
>> +#define ST_LSM6DSX_GYRO_FS_245_GAIN IIO_DEGREE_TO_RAD(4375)
>> +#define ST_LSM6DSX_GYRO_FS_500_GAIN IIO_DEGREE_TO_RAD(8750)
>> +#define ST_LSM6DSX_GYRO_FS_1000_GAIN IIO_DEGREE_TO_RAD(17500)
>> +#define ST_LSM6DSX_GYRO_FS_2000_GAIN IIO_DEGREE_TO_RAD(70000)
>> +
>> +struct st_lsm6dsx_odr {
>> + u16 hz;
>> + u8 val;
>> +};
>> +
>> +#define ST_LSM6DSX_ODR_LIST_SIZE 6
>> +struct st_lsm6dsx_odr_table_entry {
>> + struct st_lsm6dsx_reg reg;
>> + struct st_lsm6dsx_odr odr_avl[ST_LSM6DSX_ODR_LIST_SIZE];
>> +};
>> +
>> +static const struct st_lsm6dsx_odr_table_entry st_lsm6dsx_odr_table[] = {
>> + [ST_LSM6DSX_ID_ACC] = {
>> + .reg = {
>> + .addr = ST_LSM6DSX_REG_ACC_ODR_ADDR,
>> + .mask = ST_LSM6DSX_REG_ACC_ODR_MASK,
>> + },
>> + .odr_avl[0] = { 13, 0x01 },
>> + .odr_avl[1] = { 26, 0x02 },
>> + .odr_avl[2] = { 52, 0x03 },
>> + .odr_avl[3] = { 104, 0x04 },
>> + .odr_avl[4] = { 208, 0x05 },
>> + .odr_avl[5] = { 416, 0x06 },
>> + },
>> + [ST_LSM6DSX_ID_GYRO] = {
>> + .reg = {
>> + .addr = ST_LSM6DSX_REG_GYRO_ODR_ADDR,
>> + .mask = ST_LSM6DSX_REG_GYRO_ODR_MASK,
>> + },
>> + .odr_avl[0] = { 13, 0x01 },
>> + .odr_avl[1] = { 26, 0x02 },
>> + .odr_avl[2] = { 52, 0x03 },
>> + .odr_avl[3] = { 104, 0x04 },
>> + .odr_avl[4] = { 208, 0x05 },
>> + .odr_avl[5] = { 416, 0x06 },
>> + }
>> +};
>> +
>> +struct st_lsm6dsx_fs {
>> + u32 gain;
>> + u8 val;
>> +};
>> +
>> +#define ST_LSM6DSX_FS_LIST_SIZE 4
>> +struct st_lsm6dsx_fs_table_entry {
>> + struct st_lsm6dsx_reg reg;
>> + struct st_lsm6dsx_fs fs_avl[ST_LSM6DSX_FS_LIST_SIZE];
>> +};
>> +
>> +static const struct st_lsm6dsx_fs_table_entry st_lsm6dsx_fs_table[] = {
>> + [ST_LSM6DSX_ID_ACC] = {
>> + .reg = {
>> + .addr = ST_LSM6DSX_REG_ACC_FS_ADDR,
>> + .mask = ST_LSM6DSX_REG_ACC_FS_MASK,
>> + },
>> + .fs_avl[0] = { ST_LSM6DSX_ACC_FS_2G_GAIN, 0x0 },
>> + .fs_avl[1] = { ST_LSM6DSX_ACC_FS_4G_GAIN, 0x2 },
>> + .fs_avl[2] = { ST_LSM6DSX_ACC_FS_8G_GAIN, 0x3 },
>> + .fs_avl[3] = { ST_LSM6DSX_ACC_FS_16G_GAIN, 0x1 },
>> + },
>> + [ST_LSM6DSX_ID_GYRO] = {
>> + .reg = {
>> + .addr = ST_LSM6DSX_REG_GYRO_FS_ADDR,
>> + .mask = ST_LSM6DSX_REG_GYRO_FS_MASK,
>> + },
>> + .fs_avl[0] = { ST_LSM6DSX_GYRO_FS_245_GAIN, 0x0 },
>> + .fs_avl[1] = { ST_LSM6DSX_GYRO_FS_500_GAIN, 0x1 },
>> + .fs_avl[2] = { ST_LSM6DSX_GYRO_FS_1000_GAIN, 0x2 },
>> + .fs_avl[3] = { ST_LSM6DSX_GYRO_FS_2000_GAIN, 0x3 },
>> + }
>> +};
>> +
>> +static const struct st_lsm6dsx_settings st_lsm6dsx_sensor_settings[] = {
>> + {
>> + .wai = ST_LSM6DS3_WHOAMI,
>> + .max_fifo_size = ST_LSM6DS3_MAX_FIFO_SIZE,
>> + },
>> + {
>> + .wai = ST_LSM6DSM_WHOAMI,
>> + .max_fifo_size = ST_LSM6DSM_MAX_FIFO_SIZE,
>> + },
>> +};
>> +
>> +static const struct iio_chan_spec st_lsm6dsx_acc_channels[] = {
>
> can't be have #defines for the channels as most drivers do? this is highly
> repetitive
>
>> + {
>> + .type = IIO_ACCEL,
>> + .address = ST_LSM6DSX_REG_ACC_OUT_X_L_ADDR,
>> + .modified = 1,
>> + .channel2 = IIO_MOD_X,
>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> + BIT(IIO_CHAN_INFO_SCALE),
>> + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
>> + .scan_index = 0,
>> + .scan_type = {
>> + .sign = 's',
>> + .realbits = 16,
>> + .storagebits = 16,
>> + .endianness = IIO_LE,
>> + },
>> + },
>> + {
>> + .type = IIO_ACCEL,
>> + .address = ST_LSM6DSX_REG_ACC_OUT_Y_L_ADDR,
>> + .modified = 1,
>> + .channel2 = IIO_MOD_Y,
>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> + BIT(IIO_CHAN_INFO_SCALE),
>> + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
>> + .scan_index = 1,
>> + .scan_type = {
>> + .sign = 's',
>> + .realbits = 16,
>> + .storagebits = 16,
>> + .endianness = IIO_LE,
>> + },
>> + },
>> + {
>> + .type = IIO_ACCEL,
>> + .address = ST_LSM6DSX_REG_ACC_OUT_Z_L_ADDR,
>> + .modified = 1,
>> + .channel2 = IIO_MOD_Z,
>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> + BIT(IIO_CHAN_INFO_SCALE),
>> + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
>> + .scan_index = 2,
>> + .scan_type = {
>> + .sign = 's',
>> + .realbits = 16,
>> + .storagebits = 16,
>> + .endianness = IIO_LE,
>> + },
>> + },
>> + IIO_CHAN_SOFT_TIMESTAMP(3),
>> +};
>> +
>> +static const struct iio_chan_spec st_lsm6dsx_gyro_channels[] = {
>> + {
>> + .type = IIO_ANGL_VEL,
>> + .address = ST_LSM6DSX_REG_GYRO_OUT_X_L_ADDR,
>> + .modified = 1,
>> + .channel2 = IIO_MOD_X,
>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> + BIT(IIO_CHAN_INFO_SCALE),
>> + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
>> + .scan_index = 0,
>> + .scan_type = {
>> + .sign = 's',
>> + .realbits = 16,
>> + .storagebits = 16,
>> + .endianness = IIO_LE,
>> + },
>> + },
>> + {
>> + .type = IIO_ANGL_VEL,
>> + .address = ST_LSM6DSX_REG_GYRO_OUT_Y_L_ADDR,
>> + .modified = 1,
>> + .channel2 = IIO_MOD_Y,
>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> + BIT(IIO_CHAN_INFO_SCALE),
>> + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
>> + .scan_index = 1,
>> + .scan_type = {
>> + .sign = 's',
>> + .realbits = 16,
>> + .storagebits = 16,
>> + .endianness = IIO_LE,
>> + },
>> + },
>> + {
>> + .type = IIO_ANGL_VEL,
>> + .address = ST_LSM6DSX_REG_GYRO_OUT_Z_L_ADDR,
>> + .modified = 1,
>> + .channel2 = IIO_MOD_Z,
>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> + BIT(IIO_CHAN_INFO_SCALE),
>> + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
>> + .scan_index = 2,
>> + .scan_type = {
>> + .sign = 's',
>> + .realbits = 16,
>> + .storagebits = 16,
>> + .endianness = IIO_LE,
>> + },
>> + },
>> + IIO_CHAN_SOFT_TIMESTAMP(3),
>> +};
>> +
>> +int st_lsm6dsx_write_with_mask(struct st_lsm6dsx_hw *hw, u8 addr, u8 mask,
>> + u8 val)
>> +{
>> + u8 data;
>> + int err;
>> +
>> + mutex_lock(&hw->lock);
>> +
>> + err = hw->tf->read(hw->dev, addr, sizeof(data), &data);
>> + if (err < 0) {
>> + dev_err(hw->dev, "failed to read %02x register\n", addr);
>> + goto out;
>> + }
>> +
>> + data = (data & ~mask) | ((val << __ffs(mask)) & mask);
>> +
>> + err = hw->tf->write(hw->dev, addr, sizeof(data), &data);
>> + if (err < 0)
>> + dev_err(hw->dev, "failed to write %02x register\n", addr);
>> +
>> +out:
>> + mutex_unlock(&hw->lock);
>> +
>> + return err;
>> +}
>> +
>> +static int st_lsm6dsx_check_whoami(struct st_lsm6dsx_hw *hw)
>> +{
>> + int err, i;
>
> it is not clear when you use 'ret' or 'err'
>
>> + u8 data;
>> +
>> + err = hw->tf->read(hw->dev, ST_LSM6DSX_REG_WHOAMI_ADDR, sizeof(data),
>> + &data);
>> + if (err < 0) {
>> + dev_err(hw->dev, "failed to read whoami register\n");
>> + return err;
>> + }
>> +
>> + for (i = 0; i < ARRAY_SIZE(st_lsm6dsx_sensor_settings); i++) {
>> + if (data == st_lsm6dsx_sensor_settings[i].wai) {
>> + hw->settings = &st_lsm6dsx_sensor_settings[i];
>> + break;
>> + }
>> + }
>> +
>> + if (i == ARRAY_SIZE(st_lsm6dsx_sensor_settings)) {
>> + dev_err(hw->dev, "unsupported whoami [%02x]\n", data);
>> + return -ENODEV;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static int st_lsm6dsx_set_fs(struct st_lsm6dsx_sensor *sensor, u32 gain)
>> +{
>> + enum st_lsm6dsx_sensor_id id = sensor->id;
>> + int i, err;
>> + u8 val;
>> +
>> + for (i = 0; i < ST_LSM6DSX_FS_LIST_SIZE; i++)
>> + if (st_lsm6dsx_fs_table[id].fs_avl[i].gain == gain)
>> + break;
>> +
>> + if (i == ST_LSM6DSX_FS_LIST_SIZE)
>> + return -EINVAL;
>> +
>> + val = st_lsm6dsx_fs_table[id].fs_avl[i].val;
>> + err = st_lsm6dsx_write_with_mask(sensor->hw,
>> + st_lsm6dsx_fs_table[id].reg.addr,
>> + st_lsm6dsx_fs_table[id].reg.mask,
>> + val);
>> + if (err < 0)
>> + return err;
>> +
>> + sensor->gain = gain;
>> +
>> + return 0;
>> +}
>> +
>> +static int st_lsm6dsx_set_odr(struct st_lsm6dsx_sensor *sensor, u16 odr)
>> +{
>> + enum st_lsm6dsx_sensor_id id = sensor->id;
>> + int i, err, val;
>
> val could be u8
>
>> +
>> + for (i = 0; i < ST_LSM6DSX_ODR_LIST_SIZE; i++)
>> + if (st_lsm6dsx_odr_table[id].odr_avl[i].hz == odr)
>> + break;
>> +
>> + if (i == ST_LSM6DSX_ODR_LIST_SIZE)
>> + return -EINVAL;
>> +
>> + val = st_lsm6dsx_odr_table[id].odr_avl[i].val;
>> + err = st_lsm6dsx_write_with_mask(sensor->hw,
>> + st_lsm6dsx_odr_table[id].reg.addr,
>> + st_lsm6dsx_odr_table[id].reg.mask,
>> + val);
>> + if (err < 0)
>> + return err;
>> +
>> + sensor->odr = odr;
>> +
>> + return 0;
>> +}
>> +
>> +int st_lsm6dsx_sensor_enable(struct st_lsm6dsx_sensor *sensor)
>> +{
>> + int err;
>> +
>> + err = st_lsm6dsx_set_odr(sensor, sensor->odr);
>> + if (err < 0)
>> + return err;
>> +
>> + sensor->hw->enable_mask |= BIT(sensor->id);
>> +
>> + return 0;
>> +}
>> +
>> +int st_lsm6dsx_sensor_disable(struct st_lsm6dsx_sensor *sensor)
>> +{
>> + enum st_lsm6dsx_sensor_id id = sensor->id;
>> + int err;
>> +
>> + err = st_lsm6dsx_write_with_mask(sensor->hw,
>> + st_lsm6dsx_odr_table[id].reg.addr,
>> + st_lsm6dsx_odr_table[id].reg.mask, 0);
>> + if (err < 0)
>> + return err;
>> +
>> + sensor->hw->enable_mask &= ~BIT(id);
>> +
>> + return 0;
>> +}
>> +
>> +static int st_lsm6dsx_read_oneshot(struct st_lsm6dsx_sensor *sensor,
>> + u8 addr, int *val)
>> +{
>> + int err, delay;
>> + u8 data[2];
>
> data should be __le16 not an array[2] u8
>
>> + err = st_lsm6dsx_sensor_enable(sensor);
>> + if (err < 0)
>> + return err;
>> +
>> + delay = 1000000 / sensor->odr;
>> + usleep_range(delay, 2 * delay);
>> +
>> + err = sensor->hw->tf->read(sensor->hw->dev, addr, sizeof(data), data);
>> + if (err < 0)
>> + return err;
>> +
>> + st_lsm6dsx_sensor_disable(sensor);
>> +
>> + *val = (s16)get_unaligned_le16(data);
>
> if the variable's type is le16, I think we don't need the get_unaligned()
> anymore
>
>> +
>> + return IIO_VAL_INT;
>> +}
>> +
>> +static int st_lsm6dsx_read_raw(struct iio_dev *iio_dev,
>> + struct iio_chan_spec const *ch,
>> + int *val, int *val2, long mask)
>> +{
>> + struct st_lsm6dsx_sensor *sensor = iio_priv(iio_dev);
>> + int ret;
>> +
>> + ret = iio_device_claim_direct_mode(iio_dev);
>> + if (ret)
>> + return ret;
>> +
>> + switch (mask) {
>> + case IIO_CHAN_INFO_RAW:
>> + ret = st_lsm6dsx_read_oneshot(sensor, ch->address, val);
>> + break;
>> + case IIO_CHAN_INFO_SAMP_FREQ:
>> + *val = sensor->odr;
>> + ret = IIO_VAL_INT;
>> + break;
>> + case IIO_CHAN_INFO_SCALE:
>> + *val = 0;
>> + *val2 = sensor->gain;
>> + ret = IIO_VAL_INT_PLUS_MICRO;
>> + break;
>> + default:
>> + ret = -EINVAL;
>> + break;
>> + }
>> +
>> + iio_device_release_direct_mode(iio_dev);
>> +
>> + return ret;
>> +}
>> +
>> +static int st_lsm6dsx_write_raw(struct iio_dev *iio_dev,
>> + struct iio_chan_spec const *chan,
>> + int val, int val2, long mask)
>> +{
>> + struct st_lsm6dsx_sensor *sensor = iio_priv(iio_dev);
>> + int err;
>> +
>> + err = iio_device_claim_direct_mode(iio_dev);
>> + if (err)
>> + return err;
>> +
>> + switch (mask) {
>> + case IIO_CHAN_INFO_SCALE:
>> + err = st_lsm6dsx_set_fs(sensor, val2);
>> + break;
>> + case IIO_CHAN_INFO_SAMP_FREQ:
>> + err = st_lsm6dsx_set_odr(sensor, val);
>> + break;
>> + default:
>> + err = -EINVAL;
>> + break;
>> + }
>> +
>> + iio_device_release_direct_mode(iio_dev);
>> +
>> + return err;
>> +}
>> +
>> +static int st_lsm6dsx_set_watermark(struct iio_dev *iio_dev, unsigned int val)
>> +{
>> + struct st_lsm6dsx_sensor *sensor = iio_priv(iio_dev);
>> + struct st_lsm6dsx_hw *hw = sensor->hw;
>> + int err, max_fifo_len;
>> +
>> + max_fifo_len = hw->settings->max_fifo_size / ST_LSM6DSX_SAMPLE_SIZE;
>> + if (val < 1 || val > max_fifo_len)
>> + return -EINVAL;
>> +
>> + err = st_lsm6dsx_update_watermark(sensor, val);
>> + if (err < 0)
>> + return err;
>> +
>> + sensor->watermark = val;
>> +
>> + return 0;
>> +}
>> +
>> +static ssize_t
>> +st_lsm6dsx_sysfs_sampling_frequency_avl(struct device *dev,
>> + struct device_attribute *attr,
>> + char *buf)
>> +{
>> + struct st_lsm6dsx_sensor *sensor = iio_priv(dev_get_drvdata(dev));
>> + enum st_lsm6dsx_sensor_id id = sensor->id;
>> + int i, len = 0;
>> +
>> + for (i = 0; i < ST_LSM6DSX_ODR_LIST_SIZE; i++)
>> + len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
>> + st_lsm6dsx_odr_table[id].odr_avl[i].hz);
>> + buf[len - 1] = '\n';
>> +
>> + return len;
>> +}
>> +
>> +static ssize_t st_lsm6dsx_sysfs_scale_avail(struct device *dev,
>> + struct device_attribute *attr,
>> + char *buf)
>> +{
>> + struct st_lsm6dsx_sensor *sensor = iio_priv(dev_get_drvdata(dev));
>> + enum st_lsm6dsx_sensor_id id = sensor->id;
>> + int i, len = 0;
>> +
>> + for (i = 0; i < ST_LSM6DSX_FS_LIST_SIZE; i++)
>> + len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06u ",
>> + st_lsm6dsx_fs_table[id].fs_avl[i].gain);
>> + buf[len - 1] = '\n';
>> +
>> + return len;
>> +}
>> +
>> +static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(st_lsm6dsx_sysfs_sampling_frequency_avl);
>> +static IIO_DEVICE_ATTR(in_accel_scale_available, 0444,
>> + st_lsm6dsx_sysfs_scale_avail, NULL, 0);
>> +static IIO_DEVICE_ATTR(in_anglvel_scale_available, 0444,
>> + st_lsm6dsx_sysfs_scale_avail, NULL, 0);
>> +
>> +static struct attribute *st_lsm6dsx_acc_attributes[] = {
>> + &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
>> + &iio_dev_attr_in_accel_scale_available.dev_attr.attr,
>> + NULL,
>> +};
>> +
>> +static const struct attribute_group st_lsm6dsx_acc_attribute_group = {
>> + .attrs = st_lsm6dsx_acc_attributes,
>> +};
>> +
>> +static const struct iio_info st_lsm6dsx_acc_info = {
>> + .driver_module = THIS_MODULE,
>> + .attrs = &st_lsm6dsx_acc_attribute_group,
>> + .read_raw = st_lsm6dsx_read_raw,
>> + .write_raw = st_lsm6dsx_write_raw,
>> + .hwfifo_set_watermark = st_lsm6dsx_set_watermark,
>> +};
>> +
>> +static struct attribute *st_lsm6dsx_gyro_attributes[] = {
>> + &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
>> + &iio_dev_attr_in_anglvel_scale_available.dev_attr.attr,
>> + NULL,
>> +};
>> +
>> +static const struct attribute_group st_lsm6dsx_gyro_attribute_group = {
>> + .attrs = st_lsm6dsx_gyro_attributes,
>> +};
>> +
>> +static const struct iio_info st_lsm6dsx_gyro_info = {
>> + .driver_module = THIS_MODULE,
>> + .attrs = &st_lsm6dsx_gyro_attribute_group,
>> + .read_raw = st_lsm6dsx_read_raw,
>> + .write_raw = st_lsm6dsx_write_raw,
>> + .hwfifo_set_watermark = st_lsm6dsx_set_watermark,
>> +};
>> +
>> +static const unsigned long st_lsm6dsx_available_scan_masks[] = {0x7, 0x0};
>> +
>> +static int st_lsm6dsx_init_device(struct st_lsm6dsx_hw *hw)
>> +{
>> + int err;
>> + u8 data;
>> +
>> + data = ST_LSM6DSX_REG_RESET_MASK;
>> + err = hw->tf->write(hw->dev, ST_LSM6DSX_REG_RESET_ADDR, sizeof(data),
>> + &data);
>> + if (err < 0)
>> + return err;
>> +
>> + msleep(200);
>> +
>> + /* latch interrupts */
>> + err = st_lsm6dsx_write_with_mask(hw, ST_LSM6DSX_REG_LIR_ADDR,
>> + ST_LSM6DSX_REG_LIR_MASK, 1);
>> + if (err < 0)
>> + return err;
>> +
>> + /* enable BDU */
>
> whatever BDU is :)
>
>> + err = st_lsm6dsx_write_with_mask(hw, ST_LSM6DSX_REG_BDU_ADDR,
>> + ST_LSM6DSX_REG_BDU_MASK, 1);
>> + if (err < 0)
>> + return err;
>> +
>> + err = st_lsm6dsx_write_with_mask(hw, ST_LSM6DSX_REG_ROUNDING_ADDR,
>> + ST_LSM6DSX_REG_ROUNDING_MASK, 1);
>> + if (err < 0)
>> + return err;
>> +
>> + /* enable FIFO watermak interrupt */
>> + err = st_lsm6dsx_write_with_mask(hw, ST_LSM6DSX_REG_INT1_ADDR,
>> + ST_LSM6DSX_REG_FIFO_FTH_IRQ_MASK, 1);
>> + if (err < 0)
>> + return err;
>> +
>> + /* redirect INT2 on INT1 */
>> + return st_lsm6dsx_write_with_mask(hw, ST_LSM6DSX_REG_INT2_ON_INT1_ADDR,
>> + ST_LSM6DSX_REG_INT2_ON_INT1_MASK, 1);
>> +}
>> +
>> +static struct iio_dev *st_lsm6dsx_alloc_iiodev(struct st_lsm6dsx_hw *hw,
>> + enum st_lsm6dsx_sensor_id id)
>> +{
>> + struct st_lsm6dsx_sensor *sensor;
>> + struct iio_dev *iio_dev;
>> +
>> + iio_dev = devm_iio_device_alloc(hw->dev, sizeof(*sensor));
>> + if (!iio_dev)
>> + return NULL;
>> +
>> + iio_dev->modes = INDIO_DIRECT_MODE;
>> + iio_dev->dev.parent = hw->dev;
>> + iio_dev->available_scan_masks = st_lsm6dsx_available_scan_masks;
>> +
>> + sensor = iio_priv(iio_dev);
>> + sensor->id = id;
>> + sensor->hw = hw;
>> + sensor->odr = st_lsm6dsx_odr_table[id].odr_avl[0].hz;
>> + sensor->gain = st_lsm6dsx_fs_table[id].fs_avl[0].gain;
>> + sensor->watermark = 1;
>> +
>> + switch (id) {
>> + case ST_LSM6DSX_ID_ACC:
>> + iio_dev->channels = st_lsm6dsx_acc_channels;
>> + iio_dev->num_channels = ARRAY_SIZE(st_lsm6dsx_acc_channels);
>> + iio_dev->name = "lsm6dsx_accel";
>> + iio_dev->info = &st_lsm6dsx_acc_info;
>> +
>> + sensor->decimator_mask = ST_LSM6DSX_REG_ACC_DEC_MASK;
>> + break;
>> + case ST_LSM6DSX_ID_GYRO:
>> + iio_dev->channels = st_lsm6dsx_gyro_channels;
>> + iio_dev->num_channels = ARRAY_SIZE(st_lsm6dsx_gyro_channels);
>> + iio_dev->name = "lsm6dsx_gyro";
>> + iio_dev->info = &st_lsm6dsx_gyro_info;
>> +
>> + sensor->decimator_mask = ST_LSM6DSX_REG_GYRO_DEC_MASK;
>> + break;
>> + default:
>> + return NULL;
>> + }
>> +
>> + return iio_dev;
>> +}
>> +
>> +int st_lsm6dsx_probe(struct st_lsm6dsx_hw *hw)
>> +{
>> + int i, err;
>> +
>> + mutex_init(&hw->lock);
>> +
>> + err = st_lsm6dsx_check_whoami(hw);
>> + if (err < 0)
>> + return err;
>> +
>> + for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) {
>> + hw->iio_devs[i] = st_lsm6dsx_alloc_iiodev(hw, i);
>> + if (!hw->iio_devs[i])
>> + return -ENOMEM;
>> + }
>> +
>> + err = st_lsm6dsx_init_device(hw);
>> + if (err < 0)
>> + return err;
>> +
>> + if (hw->irq > 0) {
>> + err = st_lsm6dsx_allocate_rings(hw);
>> + if (err < 0)
>> + return err;
>> + }
>> +
>> + for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) {
>> + err = devm_iio_device_register(hw->dev, hw->iio_devs[i]);
>> + if (err)
>> + return err;
>> + }
>> +
>> + return 0;
>> +}
>> +EXPORT_SYMBOL(st_lsm6dsx_probe);
>> +
>> +MODULE_AUTHOR("Lorenzo Bianconi <lorenzo.bianconi@st.com>");
>> +MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
>> +MODULE_DESCRIPTION("STMicroelectronics st_lsm6dsx driver");
>> +MODULE_LICENSE("GPL v2");
>> diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c
>> new file mode 100644
>> index 0000000..c80e624
>> --- /dev/null
>> +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c
>> @@ -0,0 +1,111 @@
>> +/*
>> + * STMicroelectronics st_lsm6dsx i2c driver
>> + *
>> + * Copyright 2016 STMicroelectronics Inc.
>> + *
>> + * Lorenzo Bianconi <lorenzo.bianconi@st.com>
>> + * Denis Ciocca <denis.ciocca@st.com>
>> + *
>> + * Licensed under the GPL-2.
>> + */
>> +
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/i2c.h>
>> +#include <linux/slab.h>
>> +#include <linux/of.h>
>> +
>> +#include "st_lsm6dsx.h"
>> +
>> +static int st_lsm6dsx_i2c_read(struct device *dev, u8 addr, int len, u8 *data)
>> +{
>> + struct i2c_client *client = to_i2c_client(dev);
>> + struct i2c_msg msg[2];
>
> is this basically i2c_smbus_read_i2c_block_data()?
>
>> +
>> + msg[0].addr = client->addr;
>> + msg[0].flags = client->flags;
>> + msg[0].len = 1;
>> + msg[0].buf = &addr;
>> +
>> + msg[1].addr = client->addr;
>> + msg[1].flags = client->flags | I2C_M_RD;
>> + msg[1].len = len;
>> + msg[1].buf = data;
>> +
>> + return i2c_transfer(client->adapter, msg, 2);
>> +}
>> +
>> +static int st_lsm6dsx_i2c_write(struct device *dev, u8 addr, int len, u8 *data)
>> +{
>> + struct i2c_client *client = to_i2c_client(dev);
>> + struct i2c_msg msg;
>> + u8 send[len + 1];
>> +
>> + send[0] = addr;
>> + memcpy(&send[1], data, len * sizeof(u8));
>> +
>> + msg.addr = client->addr;
>> + msg.flags = client->flags;
>> + msg.len = len + 1;
>> + msg.buf = send;
>> +
>> + return i2c_transfer(client->adapter, &msg, 1);
>> +}
>> +
>> +static const struct st_lsm6dsx_transfer_function st_lsm6dsx_transfer_fn = {
>> + .read = st_lsm6dsx_i2c_read,
>> + .write = st_lsm6dsx_i2c_write,
>> +};
>> +
>> +static int st_lsm6dsx_i2c_probe(struct i2c_client *client,
>> + const struct i2c_device_id *id)
>> +{
>> + struct st_lsm6dsx_hw *hw;
>> +
>> + hw = devm_kzalloc(&client->dev, sizeof(*hw), GFP_KERNEL);
>> + if (!hw)
>> + return -ENOMEM;
>> +
>> + i2c_set_clientdata(client, hw);
>> + hw->name = client->name;
>> + hw->dev = &client->dev;
>> + hw->irq = client->irq;
>> + hw->tf = &st_lsm6dsx_transfer_fn;
>> +
>> + return st_lsm6dsx_probe(hw);
>> +}
>> +
>> +static const struct of_device_id st_lsm6dsx_i2c_of_match[] = {
>> + {
>> + .compatible = "st,lsm6ds3",
>> + .data = ST_LSM6DS3_DEV_NAME,
>> + },
>> + {
>> + .compatible = "st,lsm6dsm",
>> + .data = ST_LSM6DSM_DEV_NAME,
>> + },
>> + {},
>> +};
>> +MODULE_DEVICE_TABLE(of, st_lsm6dsx_i2c_of_match);
>> +
>> +static const struct i2c_device_id st_lsm6dsx_i2c_id_table[] = {
>> + { ST_LSM6DS3_DEV_NAME },
>> + { ST_LSM6DSM_DEV_NAME },
>> + {},
>> +};
>> +MODULE_DEVICE_TABLE(i2c, st_lsm6dsx_i2c_id_table);
>> +
>> +static struct i2c_driver st_lsm6dsx_driver = {
>> + .driver = {
>> + .name = "st_lsm6dsx_i2c",
>> + .of_match_table = of_match_ptr(st_lsm6dsx_i2c_of_match),
>> + },
>> + .probe = st_lsm6dsx_i2c_probe,
>> + .id_table = st_lsm6dsx_i2c_id_table,
>> +};
>> +module_i2c_driver(st_lsm6dsx_driver);
>> +
>> +MODULE_AUTHOR("Lorenzo Bianconi <lorenzo.bianconi@st.com>");
>> +MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
>> +MODULE_DESCRIPTION("STMicroelectronics st_lsm6dsx i2c driver");
>> +MODULE_LICENSE("GPL v2");
>> diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_ring.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_ring.c
>> new file mode 100644
>> index 0000000..9a8c503
>> --- /dev/null
>> +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_ring.c
>> @@ -0,0 +1,401 @@
>> +/*
>> + * STMicroelectronics st_lsm6dsx sensor driver
>> + *
>> + * Copyright 2016 STMicroelectronics Inc.
>> + *
>> + * Lorenzo Bianconi <lorenzo.bianconi@st.com>
>> + * Denis Ciocca <denis.ciocca@st.com>
>> + *
>> + * Licensed under the GPL-2.
>> + */
>> +#include <linux/module.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/irq.h>
>> +#include <linux/iio/kfifo_buf.h>
>> +#include <asm/unaligned.h>
>> +
>> +#include "st_lsm6dsx.h"
>> +
>> +#define ST_LSM6DSX_REG_FIFO_THL_ADDR 0x06
>> +#define ST_LSM6DSX_REG_FIFO_THH_ADDR 0x07
>> +#define ST_LSM6DSX_FIFO_TH_MASK 0x0fff
>> +#define ST_LSM6DSX_REG_FIFO_DEC_GXL_ADDR 0x08
>> +#define ST_LSM6DSX_REG_FIFO_MODE_ADDR 0x0a
>> +#define ST_LSM6DSX_FIFO_MODE_MASK 0x07
>> +#define ST_LSM6DSX_FIFO_ODR_MASK 0x78
>> +#define ST_LSM6DSX_REG_FIFO_DIFFL_ADDR 0x3a
>> +#define ST_LSM6DSX_FIFO_DIFF_MASK 0x0f
>> +#define ST_LSM6DSX_FIFO_EMPTY_MASK 0x10
>> +#define ST_LSM6DSX_REG_FIFO_OUTL_ADDR 0x3e
>> +
>> +struct st_lsm6dsx_dec_entry {
>> + u8 decimator;
>> + u8 val;
>> +};
>> +
>> +static const struct st_lsm6dsx_dec_entry st_lsm6dsx_dec_table[] = {
>> + { 0, 0x0 },
>> + { 1, 0x1 },
>> + { 2, 0x2 },
>> + { 3, 0x3 },
>> + { 4, 0x4 },
>> + { 8, 0x5 },
>> + { 16, 0x6 },
>> + { 32, 0x7 },
>> +};
>> +
>> +static int st_lsm6dsx_get_decimator_val(u8 val)
>> +{
>> + int i, max_size = ARRAY_SIZE(st_lsm6dsx_dec_table);
>
> max_size could be const
>
>> +
>> + for (i = 0; i < max_size; i++)
>> + if (st_lsm6dsx_dec_table[i].decimator == val)
>> + break;
>> +
>> + return i == max_size ? 0 : st_lsm6dsx_dec_table[i].val;
>> +}
>> +
>> +static void st_lsm6dsx_get_max_min_odr(struct st_lsm6dsx_hw *hw,
>> + u16 *max_odr, u16 *min_odr)
>> +{
>> + struct st_lsm6dsx_sensor *sensor;
>> + int i;
>> +
>> + *max_odr = 0, *min_odr = ~0;
>> + for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) {
>> + sensor = iio_priv(hw->iio_devs[i]);
>> +
>> + if (!(hw->enable_mask & BIT(sensor->id)))
>> + continue;
>> +
>> + *max_odr = max_t(u16, *max_odr, sensor->odr);
>> + *min_odr = min_t(u16, *min_odr, sensor->odr);
>> + }
>> +}
>> +
>> +static int st_lsm6dsx_update_decimators(struct st_lsm6dsx_hw *hw)
>> +{
>> + struct st_lsm6dsx_sensor *sensor;
>> + u16 max_odr, min_odr, sip = 0;
>> + int err, i;
>> + u8 data;
>> +
>> + st_lsm6dsx_get_max_min_odr(hw, &max_odr, &min_odr);
>> +
>> + for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) {
>> + sensor = iio_priv(hw->iio_devs[i]);
>> +
>> + /* update fifo decimators and sample in pattern */
>> + if (hw->enable_mask & BIT(sensor->id)) {
>> + sensor->sip = sensor->odr / min_odr;
>> + sensor->decimator = max_odr / sensor->odr;
>> + data = st_lsm6dsx_get_decimator_val(sensor->decimator);
>> + } else {
>> + sensor->sip = 0;
>> + sensor->decimator = 0;
>> + data = 0;
>> + }
>> +
>> + err = st_lsm6dsx_write_with_mask(hw,
>> + ST_LSM6DSX_REG_FIFO_DEC_GXL_ADDR,
>> + sensor->decimator_mask, data);
>> + if (err < 0)
>> + return err;
>> +
>> + sip += sensor->sip;
>> + }
>> + hw->sip = sip;
>> +
>> + return 0;
>> +}
>> +
>> +static int st_lsm6dsx_set_fifo_mode(struct st_lsm6dsx_hw *hw,
>> + enum st_lsm6dsx_fifo_mode fifo_mode)
>> +{
>> + u8 data;
>> + int err;
>> +
>> + switch (fifo_mode) {
>> + case ST_LSM6DSX_FIFO_BYPASS:
>> + data = fifo_mode;
>> + break;
>> + case ST_LSM6DSX_FIFO_CONT:
>> + data = fifo_mode | 0x40;
>
> magic 0x40
>
>> + break;
>> + default:
>> + return -EINVAL;
>> + }
>> +
>> + err = hw->tf->write(hw->dev, ST_LSM6DSX_REG_FIFO_MODE_ADDR,
>> + sizeof(data), &data);
>> + if (err < 0)
>> + return err;
>> +
>> + hw->fifo_mode = fifo_mode;
>> +
>> + return 0;
>> +}
>> +
>> +int st_lsm6dsx_update_watermark(struct st_lsm6dsx_sensor *sensor, u16 watermark)
>> +{
>> + u16 fifo_watermark = ~0, cur_watermark, sip = 0;
>> + struct st_lsm6dsx_hw *hw = sensor->hw;
>> + struct st_lsm6dsx_sensor *cur_sensor;
>> + int i, err;
>> + u8 data;
>> +
>> + for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) {
>> + cur_sensor = iio_priv(hw->iio_devs[i]);
>> +
>> + if (!(hw->enable_mask & BIT(cur_sensor->id)))
>> + continue;
>> +
>> + cur_watermark = (cur_sensor == sensor) ? watermark
>> + : cur_sensor->watermark;
>> +
>> + fifo_watermark = min_t(u16, fifo_watermark, cur_watermark);
>> + sip += cur_sensor->sip;
>> + }
>> +
>> + if (!sip)
>> + return 0;
>> +
>> + fifo_watermark = max_t(u16, fifo_watermark, sip);
>> + fifo_watermark = (fifo_watermark / sip) * sip;
>> + fifo_watermark = fifo_watermark * ST_LSM6DSX_SAMPLE_DEPTH;
>> +
>> + mutex_lock(&hw->lock);
>> +
>> + err = hw->tf->read(hw->dev, ST_LSM6DSX_REG_FIFO_THH_ADDR,
>> + sizeof(data), &data);
>> + if (err < 0)
>> + goto out;
>> +
>> + fifo_watermark = ((data & ~ST_LSM6DSX_FIFO_TH_MASK) << 8) |
>> + (fifo_watermark & ST_LSM6DSX_FIFO_TH_MASK);
>> +
>> + err = hw->tf->write(hw->dev, ST_LSM6DSX_REG_FIFO_THL_ADDR,
>> + sizeof(fifo_watermark), (u8 *)&fifo_watermark);
>> +out:
>> + mutex_unlock(&hw->lock);
>> +
>> + return err < 0 ? err : 0;
>> +}
>> +
>> +static int st_lsm6dsx_read_fifo(struct st_lsm6dsx_hw *hw)
>> +{
>> + u16 fifo_len, pattern_len = hw->sip * ST_LSM6DSX_SAMPLE_SIZE;
>> + int err, acc_sip, gyro_sip, read_len, offset, samples;
>> + struct st_lsm6dsx_sensor *acc_sensor, *gyro_sensor;
>> + s64 acc_ts, acc_delta_ts, gyro_ts, gyro_delta_ts;
>> + u8 iio_buf[ALIGN(ST_LSM6DSX_SAMPLE_SIZE, sizeof(s64)) + sizeof(s64)];
>> + u8 fifo_status[2], buf[pattern_len];
>
> use __le16 fifo_status
>
>> +
>> + err = hw->tf->read(hw->dev, ST_LSM6DSX_REG_FIFO_DIFFL_ADDR,
>> + sizeof(fifo_status), fifo_status);
>> + if (err < 0)
>> + return err;
>> +
>> + if (fifo_status[1] & ST_LSM6DSX_FIFO_EMPTY_MASK)
>> + return 0;
>> +
>> + fifo_status[1] &= ST_LSM6DSX_FIFO_DIFF_MASK;
>> + fifo_len = (u16)get_unaligned_le16(fifo_status) * ST_LSM6DSX_CHAN_SIZE;
>> + samples = fifo_len / ST_LSM6DSX_SAMPLE_SIZE;
>> + fifo_len = (fifo_len / pattern_len) * pattern_len;
>> + /*
>> + * leave one complete pattern in FIFO to guarantee
>> + * proper alignment
>> + */
>> + fifo_len -= pattern_len;
>> +
>> + /* compute delta timestamp */
>> + acc_sensor = iio_priv(hw->iio_devs[ST_LSM6DSX_ID_ACC]);
>> + acc_ts = acc_sensor->ts - acc_sensor->delta_ts;
>> + acc_delta_ts = div_s64(acc_sensor->delta_ts * acc_sensor->decimator,
>> + samples);
>> +
>> + gyro_sensor = iio_priv(hw->iio_devs[ST_LSM6DSX_ID_GYRO]);
>> + gyro_ts = gyro_sensor->ts - gyro_sensor->delta_ts;
>> + gyro_delta_ts = div_s64(gyro_sensor->delta_ts * gyro_sensor->decimator,
>> + samples);
>> +
>> + for (read_len = 0; read_len < fifo_len; read_len += pattern_len) {
>> + err = hw->tf->read(hw->dev, ST_LSM6DSX_REG_FIFO_OUTL_ADDR,
>> + sizeof(buf), buf);
>> + if (err < 0)
>> + return err;
>> +
>> + gyro_sip = gyro_sensor->sip;
>> + acc_sip = acc_sensor->sip;
>> + offset = 0;
>> +
>> + while (acc_sip > 0 || gyro_sip > 0) {
>> + if (gyro_sip-- > 0) {
>> + memcpy(iio_buf, &buf[offset],
>> + ST_LSM6DSX_SAMPLE_SIZE);
>> + iio_push_to_buffers_with_timestamp(
>> + hw->iio_devs[ST_LSM6DSX_ID_GYRO],
>> + iio_buf, gyro_ts);
>> + offset += ST_LSM6DSX_SAMPLE_SIZE;
>> + gyro_ts += gyro_delta_ts;
>> + }
>> +
>> + if (acc_sip-- > 0) {
>> + memcpy(iio_buf, &buf[offset],
>> + ST_LSM6DSX_SAMPLE_SIZE);
>> + iio_push_to_buffers_with_timestamp(
>> + hw->iio_devs[ST_LSM6DSX_ID_ACC],
>> + iio_buf, acc_ts);
>> + offset += ST_LSM6DSX_SAMPLE_SIZE;
>> + acc_ts += acc_delta_ts;
>> + }
>> + }
>> + }
>> +
>> + return read_len;
>> +}
>> +
>> +static int st_lsm6dsx_flush_fifo(struct st_lsm6dsx_hw *hw)
>> +{
>> + int err;
>> +
>> + disable_irq(hw->irq);
>> +
>> + st_lsm6dsx_read_fifo(hw);
>> + err = st_lsm6dsx_set_fifo_mode(hw, ST_LSM6DSX_FIFO_BYPASS);
>> +
>> + enable_irq(hw->irq);
>> +
>> + return err;
>> +}
>> +
>> +static int st_lsm6dsx_update_fifo(struct iio_dev *iio_dev, bool enable)
>> +{
>> + struct st_lsm6dsx_sensor *sensor = iio_priv(iio_dev);
>> + struct st_lsm6dsx_hw *hw = sensor->hw;
>> + int err;
>> +
>> + if (hw->fifo_mode != ST_LSM6DSX_FIFO_BYPASS) {
>> + err = st_lsm6dsx_flush_fifo(hw);
>> + if (err < 0)
>> + return err;
>> + }
>> +
>> + err = enable ? st_lsm6dsx_sensor_enable(sensor)
>> + : st_lsm6dsx_sensor_disable(sensor);
>> + if (err < 0)
>> + return err;
>> +
>> + err = st_lsm6dsx_update_decimators(hw);
>> + if (err < 0)
>> + return err;
>> +
>> + err = st_lsm6dsx_update_watermark(sensor, sensor->watermark);
>> + if (err < 0)
>> + return err;
>> +
>> + if (hw->enable_mask) {
>> + err = st_lsm6dsx_set_fifo_mode(hw, ST_LSM6DSX_FIFO_CONT);
>> + if (err < 0)
>> + return err;
>> +
>> + sensor->ts = iio_get_time_ns(iio_dev);
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static irqreturn_t st_lsm6dsx_ring_handler_irq(int irq, void *private)
>> +{
>> + struct st_lsm6dsx_hw *hw = (struct st_lsm6dsx_hw *)private;
>> + struct st_lsm6dsx_sensor *sensor;
>> + int i;
>> +
>> + if (!hw->sip)
>> + return IRQ_NONE;
>> +
>> + for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) {
>> + sensor = iio_priv(hw->iio_devs[i]);
>> +
>> + if (sensor->sip > 0) {
>> + s64 timestamp;
>> +
>> + timestamp = iio_get_time_ns(hw->iio_devs[i]);
>> + sensor->delta_ts = timestamp - sensor->ts;
>> + sensor->ts = timestamp;
>> + }
>> + }
>> +
>> + return IRQ_WAKE_THREAD;
>> +}
>> +
>> +static irqreturn_t st_lsm6dsx_ring_handler_thread(int irq, void *private)
>> +{
>> + struct st_lsm6dsx_hw *hw = (struct st_lsm6dsx_hw *)private;
>> + int count;
>> +
>> + count = st_lsm6dsx_read_fifo(hw);
>> +
>> + return !count ? IRQ_NONE : IRQ_HANDLED;
>> +}
>> +
>> +static int st_lsm6dsx_buffer_preenable(struct iio_dev *iio_dev)
>> +{
>> + return st_lsm6dsx_update_fifo(iio_dev, true);
>> +}
>> +
>> +static int st_lsm6dsx_buffer_postdisable(struct iio_dev *iio_dev)
>> +{
>> + return st_lsm6dsx_update_fifo(iio_dev, false);
>> +}
>> +
>> +static const struct iio_buffer_setup_ops st_lsm6dsx_buffer_ops = {
>> + .preenable = st_lsm6dsx_buffer_preenable,
>> + .postdisable = st_lsm6dsx_buffer_postdisable,
>> +};
>> +
>> +int st_lsm6dsx_allocate_rings(struct st_lsm6dsx_hw *hw)
>> +{
>> + struct iio_buffer *buffer;
>> + unsigned long irq_type;
>> + int i, err;
>> +
>> + irq_type = irqd_get_trigger_type(irq_get_irq_data(hw->irq));
>> +
>> + switch (irq_type) {
>> + case IRQF_TRIGGER_HIGH:
>> + case IRQF_TRIGGER_RISING:
>> + break;
>> + default:
>> + dev_info(hw->dev,
>> + "mode %lx unsupported, using IRQF_TRIGGER_HIGH\n",
>> + irq_type);
>
> I'd rather fail than autocorrect, matter of taste probably
>
>> + irq_type = IRQF_TRIGGER_HIGH;
>> + break;
>> + }
>> +
>> + err = devm_request_threaded_irq(hw->dev, hw->irq,
>> + st_lsm6dsx_ring_handler_irq,
>> + st_lsm6dsx_ring_handler_thread,
>> + irq_type | IRQF_ONESHOT,
>> + hw->name, hw);
>> + if (err) {
>> + dev_err(hw->dev, "failed to request trigger irq %d\n",
>> + hw->irq);
>> + return err;
>> + }
>> +
>> + for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) {
>> + buffer = devm_iio_kfifo_allocate(hw->dev);
>> + if (!buffer)
>> + return -ENOMEM;
>> +
>> + iio_device_attach_buffer(hw->iio_devs[i], buffer);
>> + hw->iio_devs[i]->modes |= INDIO_BUFFER_SOFTWARE;
>> + hw->iio_devs[i]->setup_ops = &st_lsm6dsx_buffer_ops;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_spi.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_spi.c
>> new file mode 100644
>> index 0000000..262eae6
>> --- /dev/null
>> +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_spi.c
>> @@ -0,0 +1,129 @@
>> +/*
>> + * STMicroelectronics st_lsm6dsx spi driver
>> + *
>> + * Copyright 2016 STMicroelectronics Inc.
>> + *
>> + * Lorenzo Bianconi <lorenzo.bianconi@st.com>
>> + * Denis Ciocca <denis.ciocca@st.com>
>> + *
>> + * Licensed under the GPL-2.
>> + */
>> +
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/spi/spi.h>
>> +#include <linux/slab.h>
>> +#include <linux/of.h>
>> +
>> +#include "st_lsm6dsx.h"
>> +
>> +#define SENSORS_SPI_READ 0x80
>> +
>> +static int st_lsm6dsx_spi_read(struct device *dev, u8 addr, int len,
>> + u8 *data)
>> +{
>> + struct spi_device *spi = to_spi_device(dev);
>> + struct st_lsm6dsx_hw *hw = spi_get_drvdata(spi);
>> + int err;
>> +
>> + struct spi_transfer xfers[] = {
>> + {
>> + .tx_buf = hw->tb.tx_buf,
>> + .bits_per_word = 8,
>> + .len = 1,
>> + },
>> + {
>> + .rx_buf = hw->tb.rx_buf,
>> + .bits_per_word = 8,
>> + .len = len,
>> + }
>> + };
>> +
>> + hw->tb.tx_buf[0] = addr | SENSORS_SPI_READ;
>> +
>> + err = spi_sync_transfer(spi, xfers, ARRAY_SIZE(xfers));
>> + if (err < 0)
>> + return err;
>> +
>> + memcpy(data, hw->tb.rx_buf, len * sizeof(u8));
>> +
>> + return len;
>> +}
>> +
>> +static int st_lsm6dsx_spi_write(struct device *dev, u8 addr, int len,
>> + u8 *data)
>> +{
>> + struct spi_device *spi = to_spi_device(dev);
>> + struct st_lsm6dsx_hw *hw = spi_get_drvdata(spi);
>> +
>> + struct spi_transfer xfers = {
>> + .tx_buf = hw->tb.tx_buf,
>> + .bits_per_word = 8,
>> + .len = len + 1,
>> + };
>> +
>> + if (len >= ST_LSM6DSX_TX_MAX_LENGTH)
>> + return -ENOMEM;
>> +
>> + hw->tb.tx_buf[0] = addr;
>> + memcpy(&hw->tb.tx_buf[1], data, len);
>> +
>> + return spi_sync_transfer(spi, &xfers, 1);
>> +}
>> +
>> +static const struct st_lsm6dsx_transfer_function st_lsm6dsx_transfer_fn = {
>> + .read = st_lsm6dsx_spi_read,
>> + .write = st_lsm6dsx_spi_write,
>> +};
>> +
>> +static int st_lsm6dsx_spi_probe(struct spi_device *spi)
>> +{
>> + struct st_lsm6dsx_hw *hw;
>> +
>> + hw = devm_kzalloc(&spi->dev, sizeof(*hw), GFP_KERNEL);
>> + if (!hw)
>> + return -ENOMEM;
>> +
>> + spi_set_drvdata(spi, hw);
>> + hw->name = spi->modalias;
>> + hw->dev = &spi->dev;
>> + hw->irq = spi->irq;
>> + hw->tf = &st_lsm6dsx_transfer_fn;
>> +
>> + return st_lsm6dsx_probe(hw);
>> +}
>> +
>> +static const struct of_device_id st_lsm6dsx_spi_of_match[] = {
>> + {
>> + .compatible = "st,lsm6ds3",
>> + .data = ST_LSM6DS3_DEV_NAME,
>> + },
>> + {
>> + .compatible = "st,lsm6dsm",
>> + .data = ST_LSM6DSM_DEV_NAME,
>> + },
>> + {},
>> +};
>> +MODULE_DEVICE_TABLE(of, st_lsm6dsx_spi_of_match);
>> +
>> +static const struct spi_device_id st_lsm6dsx_spi_id_table[] = {
>> + { ST_LSM6DS3_DEV_NAME },
>> + { ST_LSM6DSM_DEV_NAME },
>> + {},
>> +};
>> +MODULE_DEVICE_TABLE(spi, st_lsm6dsx_spi_id_table);
>> +
>> +static struct spi_driver st_lsm6dsx_driver = {
>> + .driver = {
>> + .name = "st_lsm6dsx_spi",
>> + .of_match_table = of_match_ptr(st_lsm6dsx_spi_of_match),
>> + },
>> + .probe = st_lsm6dsx_spi_probe,
>> + .id_table = st_lsm6dsx_spi_id_table,
>> +};
>> +module_spi_driver(st_lsm6dsx_driver);
>> +
>> +MODULE_AUTHOR("Lorenzo Bianconi <lorenzo.bianconi@st.com>");
>> +MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
>> +MODULE_DESCRIPTION("STMicroelectronics st_lsm6dsx spi driver");
>> +MODULE_LICENSE("GPL v2");
>>
>
> --
>
> Peter Meerwald-Stadler
> +43-664-2444418 (mobile)
--
UNIX is Sexy: who | grep -i blonde | talk; cd ~; wine; talk; touch;
unzip; touch; strip; gasp; finger; gasp; mount; fsck; more; yes; gasp;
umount; make clean; sleep
next prev parent reply other threads:[~2016-12-09 18:29 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-30 20:05 [PATCH v2 0/2] add support to STM LSM6DS3-LSM6DSM 6-axis Mems sensor Lorenzo Bianconi
2016-11-30 20:05 ` [PATCH v2 1/2] iio: imu: add support to lsm6dsx driver Lorenzo Bianconi
2016-12-03 11:25 ` Jonathan Cameron
2016-12-09 14:35 ` Lorenzo Bianconi
2016-12-10 17:22 ` Jonathan Cameron
2016-12-14 21:06 ` Lorenzo Bianconi
2016-12-06 12:12 ` Peter Meerwald-Stadler
2016-12-09 18:29 ` Lorenzo Bianconi [this message]
2016-11-30 20:05 ` [PATCH v2 2/2] Documentation: dt: iio: add st_lsm6dsx sensor device binding Lorenzo Bianconi
2016-12-05 23:30 ` Rob Herring
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