From a45d123887044622fa08b1a48e68c7db58f84b3b Mon Sep 17 00:00:00 2001 From: Richard Tresidder Date: Fri, 11 May 2018 16:54:59 +0800 Subject: [PATCH] iio: accell: mma8452: Reduce sleep time when data not ready Modified the sleep method when data is not ready to allow for sampling > 50sps to work. Signed-off-by: Richard Tresidder Signed-off-by: Jonathan Cameron --- drivers/iio/accel/mma8452.c | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) diff --git a/drivers/iio/accel/mma8452.c b/drivers/iio/accel/mma8452.c index 7a2da7f9d4dc..7e3d82cff3d5 100644 --- a/drivers/iio/accel/mma8452.c +++ b/drivers/iio/accel/mma8452.c @@ -106,6 +106,7 @@ struct mma8452_data { u8 ctrl_reg1; u8 data_cfg; const struct mma_chip_info *chip_info; + int sleep_val; }; /** @@ -193,7 +194,11 @@ static int mma8452_drdy(struct mma8452_data *data) if ((ret & MMA8452_STATUS_DRDY) == MMA8452_STATUS_DRDY) return 0; - msleep(20); + if (data->sleep_val <= 20) + usleep_range(data->sleep_val * 250, + data->sleep_val * 500); + else + msleep(20); } dev_err(&data->client->dev, "data not ready\n"); @@ -544,6 +549,18 @@ static int mma8452_read_raw(struct iio_dev *indio_dev, return -EINVAL; } +static int mma8452_calculate_sleep(struct mma8452_data *data) +{ + int ret, i = mma8452_get_odr_index(data); + + if (mma8452_samp_freq[i][0] > 0) + ret = 1000 / mma8452_samp_freq[i][0]; + else + ret = 1000; + + return ret == 0 ? 1 : ret; +} + static int mma8452_standby(struct mma8452_data *data) { return i2c_smbus_write_byte_data(data->client, MMA8452_CTRL_REG1, @@ -700,6 +717,8 @@ static int mma8452_write_raw(struct iio_dev *indio_dev, data->ctrl_reg1 &= ~MMA8452_CTRL_DR_MASK; data->ctrl_reg1 |= i << MMA8452_CTRL_DR_SHIFT; + data->sleep_val = mma8452_calculate_sleep(data); + ret = mma8452_change_config(data, MMA8452_CTRL_REG1, data->ctrl_reg1); break; @@ -1593,6 +1612,9 @@ static int mma8452_probe(struct i2c_client *client, data->ctrl_reg1 = MMA8452_CTRL_ACTIVE | (MMA8452_CTRL_DR_DEFAULT << MMA8452_CTRL_DR_SHIFT); + + data->sleep_val = mma8452_calculate_sleep(data); + ret = i2c_smbus_write_byte_data(client, MMA8452_CTRL_REG1, data->ctrl_reg1); if (ret < 0)