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>

diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
index f9c0624505a2993e3a48d9a581faa8a26e9287de..08937a6d59db07f59c556efc74c00a6ff18bf285 100644 (file)
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
@@ -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);

diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
index c54da777945daa8745c79307d0905982b3641067..a92ddd45586c07877d4f255329953a254d17cbfd 100644 (file)
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
@@ -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);

diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_ring.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_ring.c
index 1795418438e41fa918285cb7c0bcdb6e0a0c0c20..5436d181f2dc7eb54e962bfbc330a12086f5695c 100644 (file)
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_ring.c
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_ring.c
@@ -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 @@ reset_fifo_fail:
        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);