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linux/drivers/iio/gyro/mpu3050-core.c

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/*
* MPU3050 gyroscope driver
*
* Copyright (C) 2016 Linaro Ltd.
* Author: Linus Walleij <linus.walleij@linaro.org>
*
* Based on the input subsystem driver, Copyright (C) 2011 Wistron Co.Ltd
* Joseph Lai <joseph_lai@wistron.com> and trimmed down by
* Alan Cox <alan@linux.intel.com> in turn based on bma023.c.
* Device behaviour based on a misc driver posted by Nathan Royer in 2011.
*
* TODO: add support for setting up the low pass 3dB frequency.
*/
#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/iio/buffer.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/trigger.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/pm_runtime.h>
#include <linux/random.h>
#include <linux/slab.h>
#include "mpu3050.h"
#define MPU3050_CHIP_ID 0x69
/*
* Register map: anything suffixed *_H is a big-endian high byte and always
* followed by the corresponding low byte (*_L) even though these are not
* explicitly included in the register definitions.
*/
#define MPU3050_CHIP_ID_REG 0x00
#define MPU3050_PRODUCT_ID_REG 0x01
#define MPU3050_XG_OFFS_TC 0x05
#define MPU3050_YG_OFFS_TC 0x08
#define MPU3050_ZG_OFFS_TC 0x0B
#define MPU3050_X_OFFS_USR_H 0x0C
#define MPU3050_Y_OFFS_USR_H 0x0E
#define MPU3050_Z_OFFS_USR_H 0x10
#define MPU3050_FIFO_EN 0x12
#define MPU3050_AUX_VDDIO 0x13
#define MPU3050_SLV_ADDR 0x14
#define MPU3050_SMPLRT_DIV 0x15
#define MPU3050_DLPF_FS_SYNC 0x16
#define MPU3050_INT_CFG 0x17
#define MPU3050_AUX_ADDR 0x18
#define MPU3050_INT_STATUS 0x1A
#define MPU3050_TEMP_H 0x1B
#define MPU3050_XOUT_H 0x1D
#define MPU3050_YOUT_H 0x1F
#define MPU3050_ZOUT_H 0x21
#define MPU3050_DMP_CFG1 0x35
#define MPU3050_DMP_CFG2 0x36
#define MPU3050_BANK_SEL 0x37
#define MPU3050_MEM_START_ADDR 0x38
#define MPU3050_MEM_R_W 0x39
#define MPU3050_FIFO_COUNT_H 0x3A
#define MPU3050_FIFO_R 0x3C
#define MPU3050_USR_CTRL 0x3D
#define MPU3050_PWR_MGM 0x3E
/* MPU memory bank read options */
#define MPU3050_MEM_PRFTCH BIT(5)
#define MPU3050_MEM_USER_BANK BIT(4)
/* Bits 8-11 select memory bank */
#define MPU3050_MEM_RAM_BANK_0 0
#define MPU3050_MEM_RAM_BANK_1 1
#define MPU3050_MEM_RAM_BANK_2 2
#define MPU3050_MEM_RAM_BANK_3 3
#define MPU3050_MEM_OTP_BANK_0 4
#define MPU3050_AXIS_REGS(axis) (MPU3050_XOUT_H + (axis * 2))
/* Register bits */
/* FIFO Enable */
#define MPU3050_FIFO_EN_FOOTER BIT(0)
#define MPU3050_FIFO_EN_AUX_ZOUT BIT(1)
#define MPU3050_FIFO_EN_AUX_YOUT BIT(2)
#define MPU3050_FIFO_EN_AUX_XOUT BIT(3)
#define MPU3050_FIFO_EN_GYRO_ZOUT BIT(4)
#define MPU3050_FIFO_EN_GYRO_YOUT BIT(5)
#define MPU3050_FIFO_EN_GYRO_XOUT BIT(6)
#define MPU3050_FIFO_EN_TEMP_OUT BIT(7)
/*
* Digital Low Pass filter (DLPF)
* Full Scale (FS)
* and Synchronization
*/
#define MPU3050_EXT_SYNC_NONE 0x00
#define MPU3050_EXT_SYNC_TEMP 0x20
#define MPU3050_EXT_SYNC_GYROX 0x40
#define MPU3050_EXT_SYNC_GYROY 0x60
#define MPU3050_EXT_SYNC_GYROZ 0x80
#define MPU3050_EXT_SYNC_ACCELX 0xA0
#define MPU3050_EXT_SYNC_ACCELY 0xC0
#define MPU3050_EXT_SYNC_ACCELZ 0xE0
#define MPU3050_EXT_SYNC_MASK 0xE0
#define MPU3050_EXT_SYNC_SHIFT 5
#define MPU3050_FS_250DPS 0x00
#define MPU3050_FS_500DPS 0x08
#define MPU3050_FS_1000DPS 0x10
#define MPU3050_FS_2000DPS 0x18
#define MPU3050_FS_MASK 0x18
#define MPU3050_FS_SHIFT 3
#define MPU3050_DLPF_CFG_256HZ_NOLPF2 0x00
#define MPU3050_DLPF_CFG_188HZ 0x01
#define MPU3050_DLPF_CFG_98HZ 0x02
#define MPU3050_DLPF_CFG_42HZ 0x03
#define MPU3050_DLPF_CFG_20HZ 0x04
#define MPU3050_DLPF_CFG_10HZ 0x05
#define MPU3050_DLPF_CFG_5HZ 0x06
#define MPU3050_DLPF_CFG_2100HZ_NOLPF 0x07
#define MPU3050_DLPF_CFG_MASK 0x07
#define MPU3050_DLPF_CFG_SHIFT 0
/* Interrupt config */
#define MPU3050_INT_RAW_RDY_EN BIT(0)
#define MPU3050_INT_DMP_DONE_EN BIT(1)
#define MPU3050_INT_MPU_RDY_EN BIT(2)
#define MPU3050_INT_ANYRD_2CLEAR BIT(4)
#define MPU3050_INT_LATCH_EN BIT(5)
#define MPU3050_INT_OPEN BIT(6)
#define MPU3050_INT_ACTL BIT(7)
/* Interrupt status */
#define MPU3050_INT_STATUS_RAW_RDY BIT(0)
#define MPU3050_INT_STATUS_DMP_DONE BIT(1)
#define MPU3050_INT_STATUS_MPU_RDY BIT(2)
#define MPU3050_INT_STATUS_FIFO_OVFLW BIT(7)
/* USR_CTRL */
#define MPU3050_USR_CTRL_FIFO_EN BIT(6)
#define MPU3050_USR_CTRL_AUX_IF_EN BIT(5)
#define MPU3050_USR_CTRL_AUX_IF_RST BIT(3)
#define MPU3050_USR_CTRL_FIFO_RST BIT(1)
#define MPU3050_USR_CTRL_GYRO_RST BIT(0)
/* PWR_MGM */
#define MPU3050_PWR_MGM_PLL_X 0x01
#define MPU3050_PWR_MGM_PLL_Y 0x02
#define MPU3050_PWR_MGM_PLL_Z 0x03
#define MPU3050_PWR_MGM_CLKSEL_MASK 0x07
#define MPU3050_PWR_MGM_STBY_ZG BIT(3)
#define MPU3050_PWR_MGM_STBY_YG BIT(4)
#define MPU3050_PWR_MGM_STBY_XG BIT(5)
#define MPU3050_PWR_MGM_SLEEP BIT(6)
#define MPU3050_PWR_MGM_RESET BIT(7)
#define MPU3050_PWR_MGM_MASK 0xff
/*
* Fullscale precision is (for finest precision) +/- 250 deg/s, so the full
* scale is actually 500 deg/s. All 16 bits are then used to cover this scale,
* in two's complement.
*/
static unsigned int mpu3050_fs_precision[] = {
IIO_DEGREE_TO_RAD(250),
IIO_DEGREE_TO_RAD(500),
IIO_DEGREE_TO_RAD(1000),
IIO_DEGREE_TO_RAD(2000)
};
/*
* Regulator names
*/
static const char mpu3050_reg_vdd[] = "vdd";
static const char mpu3050_reg_vlogic[] = "vlogic";
static unsigned int mpu3050_get_freq(struct mpu3050 *mpu3050)
{
unsigned int freq;
if (mpu3050->lpf == MPU3050_DLPF_CFG_256HZ_NOLPF2)
freq = 8000;
else
freq = 1000;
freq /= (mpu3050->divisor + 1);
return freq;
}
static int mpu3050_start_sampling(struct mpu3050 *mpu3050)
{
__be16 raw_val[3];
int ret;
int i;
/* Reset */
ret = regmap_update_bits(mpu3050->map, MPU3050_PWR_MGM,
MPU3050_PWR_MGM_RESET, MPU3050_PWR_MGM_RESET);
if (ret)
return ret;
/* Turn on the Z-axis PLL */
ret = regmap_update_bits(mpu3050->map, MPU3050_PWR_MGM,
MPU3050_PWR_MGM_CLKSEL_MASK,
MPU3050_PWR_MGM_PLL_Z);
if (ret)
return ret;
/* Write calibration offset registers */
for (i = 0; i < 3; i++)
raw_val[i] = cpu_to_be16(mpu3050->calibration[i]);
ret = regmap_bulk_write(mpu3050->map, MPU3050_X_OFFS_USR_H, raw_val,
sizeof(raw_val));
if (ret)
return ret;
/* Set low pass filter (sample rate), sync and full scale */
ret = regmap_write(mpu3050->map, MPU3050_DLPF_FS_SYNC,
MPU3050_EXT_SYNC_NONE << MPU3050_EXT_SYNC_SHIFT |
mpu3050->fullscale << MPU3050_FS_SHIFT |
mpu3050->lpf << MPU3050_DLPF_CFG_SHIFT);
if (ret)
return ret;
/* Set up sampling frequency */
ret = regmap_write(mpu3050->map, MPU3050_SMPLRT_DIV, mpu3050->divisor);
if (ret)
return ret;
/*
* Max 50 ms start-up time after setting DLPF_FS_SYNC
* according to the data sheet, then wait for the next sample
* at this frequency T = 1000/f ms.
*/
msleep(50 + 1000 / mpu3050_get_freq(mpu3050));
return 0;
}
static int mpu3050_set_8khz_samplerate(struct mpu3050 *mpu3050)
{
int ret;
u8 divisor;
enum mpu3050_lpf lpf;
lpf = mpu3050->lpf;
divisor = mpu3050->divisor;
mpu3050->lpf = LPF_256_HZ_NOLPF; /* 8 kHz base frequency */
mpu3050->divisor = 0; /* Divide by 1 */
ret = mpu3050_start_sampling(mpu3050);
mpu3050->lpf = lpf;
mpu3050->divisor = divisor;
return ret;
}
static int mpu3050_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2,
long mask)
{
struct mpu3050 *mpu3050 = iio_priv(indio_dev);
int ret;
__be16 raw_val;
switch (mask) {
case IIO_CHAN_INFO_OFFSET:
switch (chan->type) {
case IIO_TEMP:
/* The temperature scaling is (x+23000)/280 Celsius */
*val = 23000;
return IIO_VAL_INT;
default:
return -EINVAL;
}
case IIO_CHAN_INFO_CALIBBIAS:
switch (chan->type) {
case IIO_ANGL_VEL:
*val = mpu3050->calibration[chan->scan_index-1];
return IIO_VAL_INT;
default:
return -EINVAL;
}
case IIO_CHAN_INFO_SAMP_FREQ:
*val = mpu3050_get_freq(mpu3050);
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
switch (chan->type) {
case IIO_TEMP:
/* Millidegrees, see about temperature scaling above */
*val = 1000;
*val2 = 280;
return IIO_VAL_FRACTIONAL;
case IIO_ANGL_VEL:
/*
* Convert to the corresponding full scale in
* radians. All 16 bits are used with sign to
* span the available scale: to account for the one
* missing value if we multiply by 1/S16_MAX, instead
* multiply with 2/U16_MAX.
*/
*val = mpu3050_fs_precision[mpu3050->fullscale] * 2;
*val2 = U16_MAX;
return IIO_VAL_FRACTIONAL;
default:
return -EINVAL;
}
case IIO_CHAN_INFO_RAW:
/* Resume device */
pm_runtime_get_sync(mpu3050->dev);
mutex_lock(&mpu3050->lock);
ret = mpu3050_set_8khz_samplerate(mpu3050);
if (ret)
goto out_read_raw_unlock;
switch (chan->type) {
case IIO_TEMP:
ret = regmap_bulk_read(mpu3050->map, MPU3050_TEMP_H,
&raw_val, sizeof(raw_val));
if (ret) {
dev_err(mpu3050->dev,
"error reading temperature\n");
goto out_read_raw_unlock;
}
*val = be16_to_cpu(raw_val);
ret = IIO_VAL_INT;
goto out_read_raw_unlock;
case IIO_ANGL_VEL:
ret = regmap_bulk_read(mpu3050->map,
MPU3050_AXIS_REGS(chan->scan_index-1),
&raw_val,
sizeof(raw_val));
if (ret) {
dev_err(mpu3050->dev,
"error reading axis data\n");
goto out_read_raw_unlock;
}
*val = be16_to_cpu(raw_val);
ret = IIO_VAL_INT;
goto out_read_raw_unlock;
default:
ret = -EINVAL;
goto out_read_raw_unlock;
}
default:
break;
}
return -EINVAL;
out_read_raw_unlock:
mutex_unlock(&mpu3050->lock);
pm_runtime_mark_last_busy(mpu3050->dev);
pm_runtime_put_autosuspend(mpu3050->dev);
return ret;
}
static int mpu3050_write_raw(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
int val, int val2, long mask)
{
struct mpu3050 *mpu3050 = iio_priv(indio_dev);
/*
* Couldn't figure out a way to precalculate these at compile time.
*/
unsigned int fs250 =
DIV_ROUND_CLOSEST(mpu3050_fs_precision[0] * 1000000 * 2,
U16_MAX);
unsigned int fs500 =
DIV_ROUND_CLOSEST(mpu3050_fs_precision[1] * 1000000 * 2,
U16_MAX);
unsigned int fs1000 =
DIV_ROUND_CLOSEST(mpu3050_fs_precision[2] * 1000000 * 2,
U16_MAX);
unsigned int fs2000 =
DIV_ROUND_CLOSEST(mpu3050_fs_precision[3] * 1000000 * 2,
U16_MAX);
switch (mask) {
case IIO_CHAN_INFO_CALIBBIAS:
if (chan->type != IIO_ANGL_VEL)
return -EINVAL;
mpu3050->calibration[chan->scan_index-1] = val;
return 0;
case IIO_CHAN_INFO_SAMP_FREQ:
/*
* The max samplerate is 8000 Hz, the minimum
* 1000 / 256 ~= 4 Hz
*/
if (val < 4 || val > 8000)
return -EINVAL;
/*
* Above 1000 Hz we must turn off the digital low pass filter
* so we get a base frequency of 8kHz to the divider
*/
if (val > 1000) {
mpu3050->lpf = LPF_256_HZ_NOLPF;
mpu3050->divisor = DIV_ROUND_CLOSEST(8000, val) - 1;
return 0;
}
mpu3050->lpf = LPF_188_HZ;
mpu3050->divisor = DIV_ROUND_CLOSEST(1000, val) - 1;
return 0;
case IIO_CHAN_INFO_SCALE:
if (chan->type != IIO_ANGL_VEL)
return -EINVAL;
/*
* We support +/-250, +/-500, +/-1000 and +/2000 deg/s
* which means we need to round to the closest radians
* which will be roughly +/-4.3, +/-8.7, +/-17.5, +/-35
* rad/s. The scale is then for the 16 bits used to cover
* it 2/(2^16) of that.
*/
/* Just too large, set the max range */
if (val != 0) {
mpu3050->fullscale = FS_2000_DPS;
return 0;
}
/*
* Now we're dealing with fractions below zero in millirad/s
* do some integer interpolation and match with the closest
* fullscale in the table.
*/
if (val2 <= fs250 ||
val2 < ((fs500 + fs250) / 2))
mpu3050->fullscale = FS_250_DPS;
else if (val2 <= fs500 ||
val2 < ((fs1000 + fs500) / 2))
mpu3050->fullscale = FS_500_DPS;
else if (val2 <= fs1000 ||
val2 < ((fs2000 + fs1000) / 2))
mpu3050->fullscale = FS_1000_DPS;
else
/* Catch-all */
mpu3050->fullscale = FS_2000_DPS;
return 0;
default:
break;
}
return -EINVAL;
}
static irqreturn_t mpu3050_trigger_handler(int irq, void *p)
{
const struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
struct mpu3050 *mpu3050 = iio_priv(indio_dev);
int ret;
/*
* Temperature 1*16 bits
* Three axes 3*16 bits
* Timestamp 64 bits (4*16 bits)
* Sum total 8*16 bits
*/
__be16 hw_values[8];
s64 timestamp;
unsigned int datums_from_fifo = 0;
/*
* If we're using the hardware trigger, get the precise timestamp from
* the top half of the threaded IRQ handler. Otherwise get the
* timestamp here so it will be close in time to the actual values
* read from the registers.
*/
if (iio_trigger_using_own(indio_dev))
timestamp = mpu3050->hw_timestamp;
else
timestamp = iio_get_time_ns(indio_dev);
mutex_lock(&mpu3050->lock);
/* Using the hardware IRQ trigger? Check the buffer then. */
if (mpu3050->hw_irq_trigger) {
__be16 raw_fifocnt;
u16 fifocnt;
/* X, Y, Z + temperature */
unsigned int bytes_per_datum = 8;
bool fifo_overflow = false;
ret = regmap_bulk_read(mpu3050->map,
MPU3050_FIFO_COUNT_H,
&raw_fifocnt,
sizeof(raw_fifocnt));
if (ret)
goto out_trigger_unlock;
fifocnt = be16_to_cpu(raw_fifocnt);
if (fifocnt == 512) {
dev_info(mpu3050->dev,
"FIFO overflow! Emptying and resetting FIFO\n");
fifo_overflow = true;
/* Reset and enable the FIFO */
ret = regmap_update_bits(mpu3050->map,
MPU3050_USR_CTRL,
MPU3050_USR_CTRL_FIFO_EN |
MPU3050_USR_CTRL_FIFO_RST,
MPU3050_USR_CTRL_FIFO_EN |
MPU3050_USR_CTRL_FIFO_RST);
if (ret) {
dev_info(mpu3050->dev, "error resetting FIFO\n");
goto out_trigger_unlock;
}
mpu3050->pending_fifo_footer = false;
}
if (fifocnt)
dev_dbg(mpu3050->dev,
"%d bytes in the FIFO\n",
fifocnt);
while (!fifo_overflow && fifocnt > bytes_per_datum) {
unsigned int toread;
unsigned int offset;
__be16 fifo_values[5];
/*
* If there is a FIFO footer in the pipe, first clear
* that out. This follows the complex algorithm in the
* datasheet that states that you may never leave the
* FIFO empty after the first reading: you have to
* always leave two footer bytes in it. The footer is
* in practice just two zero bytes.
*/
if (mpu3050->pending_fifo_footer) {
toread = bytes_per_datum + 2;
offset = 0;
} else {
toread = bytes_per_datum;
offset = 1;
/* Put in some dummy value */
fifo_values[0] = 0xAAAA;
}
ret = regmap_bulk_read(mpu3050->map,
MPU3050_FIFO_R,
&fifo_values[offset],
toread);
dev_dbg(mpu3050->dev,
"%04x %04x %04x %04x %04x\n",
fifo_values[0],
fifo_values[1],
fifo_values[2],
fifo_values[3],
fifo_values[4]);
/* Index past the footer (fifo_values[0]) and push */
iio_push_to_buffers_with_timestamp(indio_dev,
&fifo_values[1],
timestamp);
fifocnt -= toread;
datums_from_fifo++;
mpu3050->pending_fifo_footer = true;
/*
* If we're emptying the FIFO, just make sure to
* check if something new appeared.
*/
if (fifocnt < bytes_per_datum) {
ret = regmap_bulk_read(mpu3050->map,
MPU3050_FIFO_COUNT_H,
&raw_fifocnt,
sizeof(raw_fifocnt));
if (ret)
goto out_trigger_unlock;
fifocnt = be16_to_cpu(raw_fifocnt);
}
if (fifocnt < bytes_per_datum)
dev_dbg(mpu3050->dev,
"%d bytes left in the FIFO\n",
fifocnt);
/*
* At this point, the timestamp that triggered the
* hardware interrupt is no longer valid for what
* we are reading (the interrupt likely fired for
* the value on the top of the FIFO), so set the
* timestamp to zero and let userspace deal with it.
*/
timestamp = 0;
}
}
/*
* If we picked some datums from the FIFO that's enough, else
* fall through and just read from the current value registers.
* This happens in two cases:
*
* - We are using some other trigger (external, like an HRTimer)
* than the sensor's own sample generator. In this case the
* sensor is just set to the max sampling frequency and we give
* the trigger a copy of the latest value every time we get here.
*
* - The hardware trigger is active but unused and we actually use
* another trigger which calls here with a frequency higher
* than what the device provides data. We will then just read
* duplicate values directly from the hardware registers.
*/
if (datums_from_fifo) {
dev_dbg(mpu3050->dev,
"read %d datums from the FIFO\n",
datums_from_fifo);
goto out_trigger_unlock;
}
ret = regmap_bulk_read(mpu3050->map, MPU3050_TEMP_H, &hw_values,
sizeof(hw_values));
if (ret) {
dev_err(mpu3050->dev,
"error reading axis data\n");
goto out_trigger_unlock;
}
iio_push_to_buffers_with_timestamp(indio_dev, hw_values, timestamp);
out_trigger_unlock:
mutex_unlock(&mpu3050->lock);
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
static int mpu3050_buffer_preenable(struct iio_dev *indio_dev)
{
struct mpu3050 *mpu3050 = iio_priv(indio_dev);
pm_runtime_get_sync(mpu3050->dev);
/* Unless we have OUR trigger active, run at full speed */
if (!mpu3050->hw_irq_trigger)
return mpu3050_set_8khz_samplerate(mpu3050);
return 0;
}
static int mpu3050_buffer_postdisable(struct iio_dev *indio_dev)
{
struct mpu3050 *mpu3050 = iio_priv(indio_dev);
pm_runtime_mark_last_busy(mpu3050->dev);
pm_runtime_put_autosuspend(mpu3050->dev);
return 0;
}
static const struct iio_buffer_setup_ops mpu3050_buffer_setup_ops = {
.preenable = mpu3050_buffer_preenable,
.postenable = iio_triggered_buffer_postenable,
.predisable = iio_triggered_buffer_predisable,
.postdisable = mpu3050_buffer_postdisable,
};
static const struct iio_mount_matrix *
mpu3050_get_mount_matrix(const struct iio_dev *indio_dev,
const struct iio_chan_spec *chan)
{
struct mpu3050 *mpu3050 = iio_priv(indio_dev);
return &mpu3050->orientation;
}
static const struct iio_chan_spec_ext_info mpu3050_ext_info[] = {
IIO_MOUNT_MATRIX(IIO_SHARED_BY_TYPE, mpu3050_get_mount_matrix),
{ },
};
#define MPU3050_AXIS_CHANNEL(axis, index) \
{ \
.type = IIO_ANGL_VEL, \
.modified = 1, \
.channel2 = IIO_MOD_##axis, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_CALIBBIAS), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\
.ext_info = mpu3050_ext_info, \
.scan_index = index, \
.scan_type = { \
.sign = 's', \
.realbits = 16, \
.storagebits = 16, \
.endianness = IIO_BE, \
}, \
}
static const struct iio_chan_spec mpu3050_channels[] = {
{
.type = IIO_TEMP,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE) |
BIT(IIO_CHAN_INFO_OFFSET),
.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
.scan_index = 0,
.scan_type = {
.sign = 's',
.realbits = 16,
.storagebits = 16,
.endianness = IIO_BE,
},
},
MPU3050_AXIS_CHANNEL(X, 1),
MPU3050_AXIS_CHANNEL(Y, 2),
MPU3050_AXIS_CHANNEL(Z, 3),
IIO_CHAN_SOFT_TIMESTAMP(4),
};
/* Four channels apart from timestamp, scan mask = 0x0f */
static const unsigned long mpu3050_scan_masks[] = { 0xf, 0 };
/*
* These are just the hardcoded factors resulting from the more elaborate
* calculations done with fractions in the scale raw get/set functions.
*/
static IIO_CONST_ATTR(anglevel_scale_available,
"0.000122070 "
"0.000274658 "
"0.000518798 "
"0.001068115");
static struct attribute *mpu3050_attributes[] = {
&iio_const_attr_anglevel_scale_available.dev_attr.attr,
NULL,
};
static const struct attribute_group mpu3050_attribute_group = {
.attrs = mpu3050_attributes,
};
static const struct iio_info mpu3050_info = {
.driver_module = THIS_MODULE,
.read_raw = mpu3050_read_raw,
.write_raw = mpu3050_write_raw,
.attrs = &mpu3050_attribute_group,
};
/**
* mpu3050_read_mem() - read MPU-3050 internal memory
* @mpu3050: device to read from
* @bank: target bank
* @addr: target address
* @len: number of bytes
* @buf: the buffer to store the read bytes in
*/
static int mpu3050_read_mem(struct mpu3050 *mpu3050,
u8 bank,
u8 addr,
u8 len,
u8 *buf)
{
int ret;
ret = regmap_write(mpu3050->map,
MPU3050_BANK_SEL,
bank);
if (ret)
return ret;
ret = regmap_write(mpu3050->map,
MPU3050_MEM_START_ADDR,
addr);
if (ret)
return ret;
return regmap_bulk_read(mpu3050->map,
MPU3050_MEM_R_W,
buf,
len);
}
static int mpu3050_hw_init(struct mpu3050 *mpu3050)
{
int ret;
u8 otp[8];
/* Reset */
ret = regmap_update_bits(mpu3050->map,
MPU3050_PWR_MGM,
MPU3050_PWR_MGM_RESET,
MPU3050_PWR_MGM_RESET);
if (ret)
return ret;
/* Turn on the PLL */
ret = regmap_update_bits(mpu3050->map,
MPU3050_PWR_MGM,
MPU3050_PWR_MGM_CLKSEL_MASK,
MPU3050_PWR_MGM_PLL_Z);
if (ret)
return ret;
/* Disable IRQs */
ret = regmap_write(mpu3050->map,
MPU3050_INT_CFG,
0);
if (ret)
return ret;
/* Read out the 8 bytes of OTP (one-time-programmable) memory */
ret = mpu3050_read_mem(mpu3050,
(MPU3050_MEM_PRFTCH |
MPU3050_MEM_USER_BANK |
MPU3050_MEM_OTP_BANK_0),
0,
sizeof(otp),
otp);
if (ret)
return ret;
/* This is device-unique data so it goes into the entropy pool */
add_device_randomness(otp, sizeof(otp));
dev_info(mpu3050->dev,
"die ID: %04X, wafer ID: %02X, A lot ID: %04X, "
"W lot ID: %03X, WP ID: %01X, rev ID: %02X\n",
/* Die ID, bits 0-12 */
(otp[1] << 8 | otp[0]) & 0x1fff,
/* Wafer ID, bits 13-17 */
((otp[2] << 8 | otp[1]) & 0x03e0) >> 5,
/* A lot ID, bits 18-33 */
((otp[4] << 16 | otp[3] << 8 | otp[2]) & 0x3fffc) >> 2,
/* W lot ID, bits 34-45 */
((otp[5] << 8 | otp[4]) & 0x3ffc) >> 2,
/* WP ID, bits 47-49 */
((otp[6] << 8 | otp[5]) & 0x0380) >> 7,
/* rev ID, bits 50-55 */
otp[6] >> 2);
return 0;
}
static int mpu3050_power_up(struct mpu3050 *mpu3050)
{
int ret;
ret = regulator_bulk_enable(ARRAY_SIZE(mpu3050->regs), mpu3050->regs);
if (ret) {
dev_err(mpu3050->dev, "cannot enable regulators\n");
return ret;
}
/*
* 20-100 ms start-up time for register read/write according to
* the datasheet, be on the safe side and wait 200 ms.
*/
msleep(200);
/* Take device out of sleep mode */
ret = regmap_update_bits(mpu3050->map, MPU3050_PWR_MGM,
MPU3050_PWR_MGM_SLEEP, 0);
if (ret) {
dev_err(mpu3050->dev, "error setting power mode\n");
return ret;
}
msleep(10);
return 0;
}
static int mpu3050_power_down(struct mpu3050 *mpu3050)
{
int ret;
/*
* Put MPU-3050 into sleep mode before cutting regulators.
* This is important, because we may not be the sole user
* of the regulator so the power may stay on after this, and
* then we would be wasting power unless we go to sleep mode
* first.
*/
ret = regmap_update_bits(mpu3050->map, MPU3050_PWR_MGM,
MPU3050_PWR_MGM_SLEEP, MPU3050_PWR_MGM_SLEEP);
if (ret)
dev_err(mpu3050->dev, "error putting to sleep\n");
ret = regulator_bulk_disable(ARRAY_SIZE(mpu3050->regs), mpu3050->regs);
if (ret)
dev_err(mpu3050->dev, "error disabling regulators\n");
return 0;
}
static irqreturn_t mpu3050_irq_handler(int irq, void *p)
{
struct iio_trigger *trig = p;
struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
struct mpu3050 *mpu3050 = iio_priv(indio_dev);
if (!mpu3050->hw_irq_trigger)
return IRQ_NONE;
/* Get the time stamp as close in time as possible */
mpu3050->hw_timestamp = iio_get_time_ns(indio_dev);
return IRQ_WAKE_THREAD;
}
static irqreturn_t mpu3050_irq_thread(int irq, void *p)
{
struct iio_trigger *trig = p;
struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
struct mpu3050 *mpu3050 = iio_priv(indio_dev);
unsigned int val;
int ret;
/* ACK IRQ and check if it was from us */
ret = regmap_read(mpu3050->map, MPU3050_INT_STATUS, &val);
if (ret) {
dev_err(mpu3050->dev, "error reading IRQ status\n");
return IRQ_HANDLED;
}
if (!(val & MPU3050_INT_STATUS_RAW_RDY))
return IRQ_NONE;
iio_trigger_poll_chained(p);
return IRQ_HANDLED;
}
/**
* mpu3050_drdy_trigger_set_state() - set data ready interrupt state
* @trig: trigger instance
* @enable: true if trigger should be enabled, false to disable
*/
static int mpu3050_drdy_trigger_set_state(struct iio_trigger *trig,
bool enable)
{
struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
struct mpu3050 *mpu3050 = iio_priv(indio_dev);
unsigned int val;
int ret;
/* Disabling trigger: disable interrupt and return */
if (!enable) {
/* Disable all interrupts */
ret = regmap_write(mpu3050->map,
MPU3050_INT_CFG,
0);
if (ret)
dev_err(mpu3050->dev, "error disabling IRQ\n");
/* Clear IRQ flag */
ret = regmap_read(mpu3050->map, MPU3050_INT_STATUS, &val);
if (ret)
dev_err(mpu3050->dev, "error clearing IRQ status\n");
/* Disable all things in the FIFO and reset it */
ret = regmap_write(mpu3050->map, MPU3050_FIFO_EN, 0);
if (ret)
dev_err(mpu3050->dev, "error disabling FIFO\n");
ret = regmap_write(mpu3050->map, MPU3050_USR_CTRL,
MPU3050_USR_CTRL_FIFO_RST);
if (ret)
dev_err(mpu3050->dev, "error resetting FIFO\n");
pm_runtime_mark_last_busy(mpu3050->dev);
pm_runtime_put_autosuspend(mpu3050->dev);
mpu3050->hw_irq_trigger = false;
return 0;
} else {
/* Else we're enabling the trigger from this point */
pm_runtime_get_sync(mpu3050->dev);
mpu3050->hw_irq_trigger = true;
/* Disable all things in the FIFO */
ret = regmap_write(mpu3050->map, MPU3050_FIFO_EN, 0);
if (ret)
return ret;
/* Reset and enable the FIFO */
ret = regmap_update_bits(mpu3050->map, MPU3050_USR_CTRL,
MPU3050_USR_CTRL_FIFO_EN |
MPU3050_USR_CTRL_FIFO_RST,
MPU3050_USR_CTRL_FIFO_EN |
MPU3050_USR_CTRL_FIFO_RST);
if (ret)
return ret;
mpu3050->pending_fifo_footer = false;
/* Turn on the FIFO for temp+X+Y+Z */
ret = regmap_write(mpu3050->map, MPU3050_FIFO_EN,
MPU3050_FIFO_EN_TEMP_OUT |
MPU3050_FIFO_EN_GYRO_XOUT |
MPU3050_FIFO_EN_GYRO_YOUT |
MPU3050_FIFO_EN_GYRO_ZOUT |
MPU3050_FIFO_EN_FOOTER);
if (ret)
return ret;
/* Configure the sample engine */
ret = mpu3050_start_sampling(mpu3050);
if (ret)
return ret;
/* Clear IRQ flag */
ret = regmap_read(mpu3050->map, MPU3050_INT_STATUS, &val);
if (ret)
dev_err(mpu3050->dev, "error clearing IRQ status\n");
/* Give us interrupts whenever there is new data ready */
val = MPU3050_INT_RAW_RDY_EN;
if (mpu3050->irq_actl)
val |= MPU3050_INT_ACTL;
if (mpu3050->irq_latch)
val |= MPU3050_INT_LATCH_EN;
if (mpu3050->irq_opendrain)
val |= MPU3050_INT_OPEN;
ret = regmap_write(mpu3050->map, MPU3050_INT_CFG, val);
if (ret)
return ret;
}
return 0;
}
static const struct iio_trigger_ops mpu3050_trigger_ops = {
.owner = THIS_MODULE,
.set_trigger_state = mpu3050_drdy_trigger_set_state,
};
static int mpu3050_trigger_probe(struct iio_dev *indio_dev, int irq)
{
struct mpu3050 *mpu3050 = iio_priv(indio_dev);
unsigned long irq_trig;
int ret;
mpu3050->trig = devm_iio_trigger_alloc(&indio_dev->dev,
"%s-dev%d",
indio_dev->name,
indio_dev->id);
if (!mpu3050->trig)
return -ENOMEM;
/* Check if IRQ is open drain */
if (of_property_read_bool(mpu3050->dev->of_node, "drive-open-drain"))
mpu3050->irq_opendrain = true;
irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq));
/*
* Configure the interrupt generator hardware to supply whatever
* the interrupt is configured for, edges low/high level low/high,
* we can provide it all.
*/
switch (irq_trig) {
case IRQF_TRIGGER_RISING:
dev_info(&indio_dev->dev,
"pulse interrupts on the rising edge\n");
break;
case IRQF_TRIGGER_FALLING:
mpu3050->irq_actl = true;
dev_info(&indio_dev->dev,
"pulse interrupts on the falling edge\n");
break;
case IRQF_TRIGGER_HIGH:
mpu3050->irq_latch = true;
dev_info(&indio_dev->dev,
"interrupts active high level\n");
/*
* With level IRQs, we mask the IRQ until it is processed,
* but with edge IRQs (pulses) we can queue several interrupts
* in the top half.
*/
irq_trig |= IRQF_ONESHOT;
break;
case IRQF_TRIGGER_LOW:
mpu3050->irq_latch = true;
mpu3050->irq_actl = true;
irq_trig |= IRQF_ONESHOT;
dev_info(&indio_dev->dev,
"interrupts active low level\n");
break;
default:
/* This is the most preferred mode, if possible */
dev_err(&indio_dev->dev,
"unsupported IRQ trigger specified (%lx), enforce "
"rising edge\n", irq_trig);
irq_trig = IRQF_TRIGGER_RISING;
break;
}
/* An open drain line can be shared with several devices */
if (mpu3050->irq_opendrain)
irq_trig |= IRQF_SHARED;
ret = request_threaded_irq(irq,
mpu3050_irq_handler,
mpu3050_irq_thread,
irq_trig,
mpu3050->trig->name,
mpu3050->trig);
if (ret) {
dev_err(mpu3050->dev,
"can't get IRQ %d, error %d\n", irq, ret);
return ret;
}
mpu3050->irq = irq;
mpu3050->trig->dev.parent = mpu3050->dev;
mpu3050->trig->ops = &mpu3050_trigger_ops;
iio_trigger_set_drvdata(mpu3050->trig, indio_dev);
ret = iio_trigger_register(mpu3050->trig);
if (ret)
return ret;
indio_dev->trig = iio_trigger_get(mpu3050->trig);
return 0;
}
int mpu3050_common_probe(struct device *dev,
struct regmap *map,
int irq,
const char *name)
{
struct iio_dev *indio_dev;
struct mpu3050 *mpu3050;
unsigned int val;
int ret;
indio_dev = devm_iio_device_alloc(dev, sizeof(*mpu3050));
if (!indio_dev)
return -ENOMEM;
mpu3050 = iio_priv(indio_dev);
mpu3050->dev = dev;
mpu3050->map = map;
mutex_init(&mpu3050->lock);
/* Default fullscale: 2000 degrees per second */
mpu3050->fullscale = FS_2000_DPS;
/* 1 kHz, divide by 100, default frequency = 10 Hz */
mpu3050->lpf = MPU3050_DLPF_CFG_188HZ;
mpu3050->divisor = 99;
/* Read the mounting matrix, if present */
ret = of_iio_read_mount_matrix(dev, "mount-matrix",
&mpu3050->orientation);
if (ret)
return ret;
/* Fetch and turn on regulators */
mpu3050->regs[0].supply = mpu3050_reg_vdd;
mpu3050->regs[1].supply = mpu3050_reg_vlogic;
ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(mpu3050->regs),
mpu3050->regs);
if (ret) {
dev_err(dev, "Cannot get regulators\n");
return ret;
}
ret = mpu3050_power_up(mpu3050);
if (ret)
return ret;
ret = regmap_read(map, MPU3050_CHIP_ID_REG, &val);
if (ret) {
dev_err(dev, "could not read device ID\n");
ret = -ENODEV;
goto err_power_down;
}
if (val != MPU3050_CHIP_ID) {
dev_err(dev, "unsupported chip id %02x\n", (u8)val);
ret = -ENODEV;
goto err_power_down;
}
ret = regmap_read(map, MPU3050_PRODUCT_ID_REG, &val);
if (ret) {
dev_err(dev, "could not read device ID\n");
ret = -ENODEV;
goto err_power_down;
}
dev_info(dev, "found MPU-3050 part no: %d, version: %d\n",
((val >> 4) & 0xf), (val & 0xf));
ret = mpu3050_hw_init(mpu3050);
if (ret)
goto err_power_down;
indio_dev->dev.parent = dev;
indio_dev->channels = mpu3050_channels;
indio_dev->num_channels = ARRAY_SIZE(mpu3050_channels);
indio_dev->info = &mpu3050_info;
indio_dev->available_scan_masks = mpu3050_scan_masks;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->name = name;
ret = iio_triggered_buffer_setup(indio_dev, iio_pollfunc_store_time,
mpu3050_trigger_handler,
&mpu3050_buffer_setup_ops);
if (ret) {
dev_err(dev, "triggered buffer setup failed\n");
goto err_power_down;
}
ret = iio_device_register(indio_dev);
if (ret) {
dev_err(dev, "device register failed\n");
goto err_cleanup_buffer;
}
dev_set_drvdata(dev, indio_dev);
/* Check if we have an assigned IRQ to use as trigger */
if (irq) {
ret = mpu3050_trigger_probe(indio_dev, irq);
if (ret)
dev_err(dev, "failed to register trigger\n");
}
/* Enable runtime PM */
pm_runtime_get_noresume(dev);
pm_runtime_set_active(dev);
pm_runtime_enable(dev);
/*
* Set autosuspend to two orders of magnitude larger than the
* start-up time. 100ms start-up time means 10000ms autosuspend,
* i.e. 10 seconds.
*/
pm_runtime_set_autosuspend_delay(dev, 10000);
pm_runtime_use_autosuspend(dev);
pm_runtime_put(dev);
return 0;
err_cleanup_buffer:
iio_triggered_buffer_cleanup(indio_dev);
err_power_down:
mpu3050_power_down(mpu3050);
return ret;
}
EXPORT_SYMBOL(mpu3050_common_probe);
int mpu3050_common_remove(struct device *dev)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct mpu3050 *mpu3050 = iio_priv(indio_dev);
pm_runtime_get_sync(dev);
pm_runtime_put_noidle(dev);
pm_runtime_disable(dev);
iio_triggered_buffer_cleanup(indio_dev);
if (mpu3050->irq)
free_irq(mpu3050->irq, mpu3050);
iio_device_unregister(indio_dev);
mpu3050_power_down(mpu3050);
return 0;
}
EXPORT_SYMBOL(mpu3050_common_remove);
#ifdef CONFIG_PM
static int mpu3050_runtime_suspend(struct device *dev)
{
return mpu3050_power_down(iio_priv(dev_get_drvdata(dev)));
}
static int mpu3050_runtime_resume(struct device *dev)
{
return mpu3050_power_up(iio_priv(dev_get_drvdata(dev)));
}
#endif /* CONFIG_PM */
const struct dev_pm_ops mpu3050_dev_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
pm_runtime_force_resume)
SET_RUNTIME_PM_OPS(mpu3050_runtime_suspend,
mpu3050_runtime_resume, NULL)
};
EXPORT_SYMBOL(mpu3050_dev_pm_ops);
MODULE_AUTHOR("Linus Walleij");
MODULE_DESCRIPTION("MPU3050 gyroscope driver");
MODULE_LICENSE("GPL");
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