| Message ID | 20210501172515.513486-4-jic23@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | IIO: Alignment fixes part 4 - bounce buffers for the hard cases. | expand |
On Sat, May 1, 2021 at 7:26 PM Jonathan Cameron <jic23@kernel.org> wrote: > From: Jonathan Cameron <Jonathan.Cameron@huawei.com> > > Fix a set of closely related issues. > 1. When using fifo_values() there was not enough space for the timestamp to > be inserted by iio_push_to_buffers_with_timestamp() > 2. fifo_values() did not meet the alignment requirement of > iio_push_to_buffers_with_timestamp() > 3. hw_values did not meet the alignment requirement either. > > 1 and 2 fixed by using new iio_push_to_buffers_with_ts_na() which has > no alignment or space padding requirements. > 3 fixed by introducing a structure that makes the space and alignment > requirements explicit. > > Fixes: 3904b28efb2c ("iio: gyro: Add driver for the MPU-3050 gyroscope") > Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> > Cc: Linus Walleij <linus.walleij@linaro.org> Again a very nice fix: Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Again I wonder how we can help driver authors to always get this right. Yours, Linus Walleij
diff --git a/drivers/iio/gyro/mpu3050-core.c b/drivers/iio/gyro/mpu3050-core.c index ac90be03332a..a7fdfe811258 100644 --- a/drivers/iio/gyro/mpu3050-core.c +++ b/drivers/iio/gyro/mpu3050-core.c @@ -462,13 +462,10 @@ static irqreturn_t mpu3050_trigger_handler(int irq, void *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]; + struct { + __be16 chans[4]; + s64 timestamp __aligned(8); + } scan; s64 timestamp; unsigned int datums_from_fifo = 0; @@ -563,9 +560,10 @@ static irqreturn_t mpu3050_trigger_handler(int irq, void *p) fifo_values[4]); /* Index past the footer (fifo_values[0]) and push */ - iio_push_to_buffers_with_timestamp(indio_dev, - &fifo_values[1], - timestamp); + iio_push_to_buffers_with_ts_na(indio_dev, + &fifo_values[1], + sizeof(__be16) * 4, + timestamp); fifocnt -= toread; datums_from_fifo++; @@ -623,15 +621,15 @@ static irqreturn_t mpu3050_trigger_handler(int irq, void *p) goto out_trigger_unlock; } - ret = regmap_bulk_read(mpu3050->map, MPU3050_TEMP_H, &hw_values, - sizeof(hw_values)); + ret = regmap_bulk_read(mpu3050->map, MPU3050_TEMP_H, scan.chans, + sizeof(scan.chans)); 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); + iio_push_to_buffers_with_timestamp(indio_dev, &scan, timestamp); out_trigger_unlock: mutex_unlock(&mpu3050->lock);