iio: imu: inv_mpu6050: replace timestamp fifo by generic timestamp

Using a fifo for storing timestamps is useless since the interrupt
is in one-shot mode, preventing the hard irq handler to be called
when the irq thread is running. Instead use the generic timestamp
function iio_pollfunc_store_time.

Signed-off-by: Jean-Baptiste Maneyrol <jmaneyrol@invensense.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Jean-Baptiste Maneyrol 2018-05-22 16:18:18 +02:00 committed by Jonathan Cameron
parent c2c8406b31
commit 3ca4fb431b
3 changed files with 2 additions and 58 deletions

View file

@ -20,8 +20,6 @@
#include <linux/jiffies.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/kfifo.h>
#include <linux/spinlock.h>
#include <linux/iio/iio.h>
#include <linux/acpi.h>
#include <linux/platform_device.h>
@ -1003,7 +1001,7 @@ int inv_mpu_core_probe(struct regmap *regmap, int irq, const char *name,
indio_dev->modes = INDIO_BUFFER_TRIGGERED;
result = devm_iio_triggered_buffer_setup(dev, indio_dev,
inv_mpu6050_irq_handler,
iio_pollfunc_store_time,
inv_mpu6050_read_fifo,
NULL);
if (result) {
@ -1016,8 +1014,6 @@ int inv_mpu_core_probe(struct regmap *regmap, int irq, const char *name,
return result;
}
INIT_KFIFO(st->timestamps);
spin_lock_init(&st->time_stamp_lock);
result = devm_iio_device_register(dev, indio_dev);
if (result) {
dev_err(dev, "IIO register fail %d\n", result);

View file

@ -12,8 +12,6 @@
*/
#include <linux/i2c.h>
#include <linux/i2c-mux.h>
#include <linux/kfifo.h>
#include <linux/spinlock.h>
#include <linux/mutex.h>
#include <linux/iio/iio.h>
#include <linux/iio/buffer.h>
@ -116,36 +114,30 @@ struct inv_mpu6050_hw {
/*
* struct inv_mpu6050_state - Driver state variables.
* @TIMESTAMP_FIFO_SIZE: fifo size for timestamp.
* @lock: Chip access lock.
* @trig: IIO trigger.
* @chip_config: Cached attribute information.
* @reg: Map of important registers.
* @hw: Other hardware-specific information.
* @chip_type: chip type.
* @time_stamp_lock: spin lock to time stamp.
* @plat_data: platform data (deprecated in favor of @orientation).
* @orientation: sensor chip orientation relative to main hardware.
* @timestamps: kfifo queue to store time stamp.
* @map regmap pointer.
* @irq interrupt number.
* @irq_mask the int_pin_cfg mask to configure interrupt type.
*/
struct inv_mpu6050_state {
#define TIMESTAMP_FIFO_SIZE 16
struct mutex lock;
struct iio_trigger *trig;
struct inv_mpu6050_chip_config chip_config;
const struct inv_mpu6050_reg_map *reg;
const struct inv_mpu6050_hw *hw;
enum inv_devices chip_type;
spinlock_t time_stamp_lock;
struct i2c_mux_core *muxc;
struct i2c_client *mux_client;
unsigned int powerup_count;
struct inv_mpu6050_platform_data plat_data;
struct iio_mount_matrix orientation;
DECLARE_KFIFO(timestamps, long long, TIMESTAMP_FIFO_SIZE);
struct regmap *map;
int irq;
u8 irq_mask;
@ -234,7 +226,6 @@ struct inv_mpu6050_state {
/* init parameters */
#define INV_MPU6050_INIT_FIFO_RATE 50
#define INV_MPU6050_TIME_STAMP_TOR 5
#define INV_MPU6050_MAX_FIFO_RATE 1000
#define INV_MPU6050_MIN_FIFO_RATE 4
#define INV_MPU6050_ONE_K_HZ 1000
@ -300,7 +291,6 @@ enum inv_mpu6050_clock_sel_e {
NUM_CLK
};
irqreturn_t inv_mpu6050_irq_handler(int irq, void *p);
irqreturn_t inv_mpu6050_read_fifo(int irq, void *p);
int inv_mpu6050_probe_trigger(struct iio_dev *indio_dev, int irq_type);
int inv_reset_fifo(struct iio_dev *indio_dev);

View file

@ -19,20 +19,9 @@
#include <linux/jiffies.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/kfifo.h>
#include <linux/poll.h>
#include "inv_mpu_iio.h"
static void inv_clear_kfifo(struct inv_mpu6050_state *st)
{
unsigned long flags;
/* take the spin lock sem to avoid interrupt kick in */
spin_lock_irqsave(&st->time_stamp_lock, flags);
kfifo_reset(&st->timestamps);
spin_unlock_irqrestore(&st->time_stamp_lock, flags);
}
int inv_reset_fifo(struct iio_dev *indio_dev)
{
int result;
@ -62,9 +51,6 @@ int inv_reset_fifo(struct iio_dev *indio_dev)
if (result)
goto reset_fifo_fail;
/* clear timestamps fifo */
inv_clear_kfifo(st);
/* enable interrupt */
if (st->chip_config.accl_fifo_enable ||
st->chip_config.gyro_fifo_enable) {
@ -98,23 +84,6 @@ int inv_reset_fifo(struct iio_dev *indio_dev)
return result;
}
/**
* inv_mpu6050_irq_handler() - Cache a timestamp at each data ready interrupt.
*/
irqreturn_t inv_mpu6050_irq_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
struct inv_mpu6050_state *st = iio_priv(indio_dev);
s64 timestamp;
timestamp = iio_get_time_ns(indio_dev);
kfifo_in_spinlocked(&st->timestamps, &timestamp, 1,
&st->time_stamp_lock);
return IRQ_WAKE_THREAD;
}
/**
* inv_mpu6050_read_fifo() - Transfer data from hardware FIFO to KFIFO.
*/
@ -127,7 +96,7 @@ irqreturn_t inv_mpu6050_read_fifo(int irq, void *p)
int result;
u8 data[INV_MPU6050_OUTPUT_DATA_SIZE];
u16 fifo_count;
s64 timestamp;
s64 timestamp = pf->timestamp;
int int_status;
mutex_lock(&st->lock);
@ -171,28 +140,17 @@ irqreturn_t inv_mpu6050_read_fifo(int irq, void *p)
goto flush_fifo;
if (fifo_count > INV_MPU6050_FIFO_THRESHOLD)
goto flush_fifo;
/* Timestamp mismatch. */
if (kfifo_len(&st->timestamps) >
fifo_count / bytes_per_datum + INV_MPU6050_TIME_STAMP_TOR)
goto flush_fifo;
do {
result = regmap_bulk_read(st->map, st->reg->fifo_r_w,
data, bytes_per_datum);
if (result)
goto flush_fifo;
result = kfifo_out(&st->timestamps, &timestamp, 1);
/* when there is no timestamp, put timestamp as 0 */
if (result == 0)
timestamp = 0;
/* skip first samples if needed */
if (st->skip_samples)
st->skip_samples--;
else
iio_push_to_buffers_with_timestamp(indio_dev, data,
timestamp);
fifo_count -= bytes_per_datum;
} while (fifo_count >= bytes_per_datum);