| From ff30884f362f28802f59a5bee9119083a2cfd9e4 Mon Sep 17 00:00:00 2001 |
| From: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com> |
| Date: Wed, 16 Nov 2016 22:15:28 +0100 |
| Subject: [PATCH] iio: common: st_sensors: fix channel data parsing |
| |
| commit 65c8aea07de11b6507efa175edb44bd8b4488218 upstream. |
| |
| Using realbits as i2c/spi read len, when that value is not byte aligned |
| (e.g 12 bits), lead to skip msb part of out data registers. |
| Fix this taking into account scan_type.shift in addition to |
| scan_type.realbits as read length: |
| |
| read_len = DIV_ROUND_UP(realbits + shift, 8) |
| |
| This fix has been tested on 8, 12, 16, 24 bit sensors |
| |
| Fixes: e7385de5291e ("iio:st_sensors: align on storagebits boundaries") |
| Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@st.com> |
| Tested-by: Linus Walleij <linus.walleij@linaro.org> |
| Cc: <Stable@vger.kernel.org> |
| Signed-off-by: Jonathan Cameron <jic23@kernel.org> |
| Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> |
| |
| diff --git a/drivers/iio/common/st_sensors/st_sensors_buffer.c b/drivers/iio/common/st_sensors/st_sensors_buffer.c |
| index d06e728cea37..950ea0726434 100644 |
| --- a/drivers/iio/common/st_sensors/st_sensors_buffer.c |
| +++ b/drivers/iio/common/st_sensors/st_sensors_buffer.c |
| @@ -30,7 +30,9 @@ static int st_sensors_get_buffer_element(struct iio_dev *indio_dev, u8 *buf) |
| |
| for_each_set_bit(i, indio_dev->active_scan_mask, num_data_channels) { |
| const struct iio_chan_spec *channel = &indio_dev->channels[i]; |
| - unsigned int bytes_to_read = channel->scan_type.realbits >> 3; |
| + unsigned int bytes_to_read = |
| + DIV_ROUND_UP(channel->scan_type.realbits + |
| + channel->scan_type.shift, 8); |
| unsigned int storage_bytes = |
| channel->scan_type.storagebits >> 3; |
| |
| diff --git a/drivers/iio/common/st_sensors/st_sensors_core.c b/drivers/iio/common/st_sensors/st_sensors_core.c |
| index 32a594675a54..f8ce75a19bae 100644 |
| --- a/drivers/iio/common/st_sensors/st_sensors_core.c |
| +++ b/drivers/iio/common/st_sensors/st_sensors_core.c |
| @@ -490,8 +490,10 @@ static int st_sensors_read_axis_data(struct iio_dev *indio_dev, |
| int err; |
| u8 *outdata; |
| struct st_sensor_data *sdata = iio_priv(indio_dev); |
| - unsigned int byte_for_channel = ch->scan_type.realbits >> 3; |
| + unsigned int byte_for_channel; |
| |
| + byte_for_channel = DIV_ROUND_UP(ch->scan_type.realbits + |
| + ch->scan_type.shift, 8); |
| outdata = kmalloc(byte_for_channel, GFP_KERNEL); |
| if (!outdata) |
| return -ENOMEM; |
| -- |
| 2.10.1 |
| |
