Re: [PATCH v4 3/4] iio: hid-sensor-magn-3d: Scan for usage attributes before setting up iio channels

From: Reyad Attiyat
Date: Tue Jul 08 2014 - 12:00:07 EST


Hey Jonathan,

Thanks for the review. I'll be sure to fix up all the formatting you
mentioned and run it through the checkpatch.pl script.

> There should be an explanation here of what has changed from one version to
> the
> next.
Will include updates in future patch notes.

> The patches should have been run through checkpatch.pl (at least one place
> below
> indicates that didn't happen).
>
> Mostly little bits left. Now I would definitely like an ack or reviewed-by
> from Srinivas for this one if at all possible.
> Any tested-bys, particularly with parts that don't have the new channel
> types, would also be good.
>
> Jonathan
>
>> drivers/iio/magnetometer/hid-sensor-magn-3d.c | 111
>> +++++++++++++++++---------
>> 1 file changed, 75 insertions(+), 36 deletions(-)
>>
>> diff --git a/drivers/iio/magnetometer/hid-sensor-magn-3d.c
>> b/drivers/iio/magnetometer/hid-sensor-magn-3d.c
>> index 41cf29e..070d20e 100644
>> --- a/drivers/iio/magnetometer/hid-sensor-magn-3d.c
>> +++ b/drivers/iio/magnetometer/hid-sensor-magn-3d.c
>> @@ -42,7 +42,8 @@ struct magn_3d_state {
>> struct hid_sensor_hub_callbacks callbacks;
>> struct hid_sensor_common common_attributes;
>> struct hid_sensor_hub_attribute_info magn[MAGN_3D_CHANNEL_MAX];
>> - u32 magn_val[MAGN_3D_CHANNEL_MAX];
>> + u32 *magn_val_addr[MAGN_3D_CHANNEL_MAX];
>> + u32 *iio_val;
>> int scale_pre_decml;
>> int scale_post_decml;
>> int scale_precision;
>> @@ -221,8 +222,8 @@ static int magn_3d_proc_event(struct
>> hid_sensor_hub_device *hsdev,
>> dev_dbg(&indio_dev->dev, "magn_3d_proc_event\n");
>> if (atomic_read(&magn_state->common_attributes.data_ready))
>> hid_sensor_push_data(indio_dev,
>> - magn_state->magn_val,
>> - sizeof(magn_state->magn_val));
>> + magn_state->iio_val,
>> + sizeof(magn_state->iio_val));
>>
>> return 0;
>> }
>> @@ -236,52 +237,99 @@ static int magn_3d_capture_sample(struct
>> hid_sensor_hub_device *hsdev,
>> struct iio_dev *indio_dev = platform_get_drvdata(priv);
>> struct magn_3d_state *magn_state = iio_priv(indio_dev);
>> int offset;
>> - int ret = -EINVAL;
>> + int ret = 0;
>> + u32 *iio_val = NULL;
>
> This has me a little confused. You have an iio_val in your state
> structure and in this function. I can't actually find anywhere where
> the elements of the one in the state structure are ever assigned to
> anything.
>
>

I assign the pointer location of iio_vals to:
u32 *magn_val_addr[MAGN_3D_CHANNEL_MAX];

I also added this array just for the locations. The assignment occurs
in the parse_report
function, after iio_vals is allocated, like this st->magn_val_addr[i]
= &(st->iio_val[*chan_count]).
I'll add a comment to explain the usage better.


>>
>> switch (usage_id) {
>> case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS:
>> case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Y_AXIS:
>> case HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_Z_AXIS:
>> offset = usage_id -
>> HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS;
>> - magn_state->magn_val[CHANNEL_SCAN_INDEX_X + offset] =
>> - *(u32 *)raw_data;
>> - ret = 0;
>> + iio_val = magn_state->magn_val_addr[CHANNEL_SCAN_INDEX_X +
>> offset];
>> +
>> break;
>> default:
>> - break;
>> + return -EINVAL;
>> }
>>
>> + if(iio_val)
>
> white space after if please.
>
>> + *iio_val = *(u32 *)raw_data;
>> + else
>> + ret = -EINVAL;
>> +
>> return ret;
>> }
>>
>> /* Parse report which is specific to an usage id*/
>> static int magn_3d_parse_report(struct platform_device *pdev,
>> struct hid_sensor_hub_device *hsdev,
>> - struct iio_chan_spec *channels,
>> + struct iio_chan_spec **channels,
>> + int *chan_count,
>> unsigned usage_id,
>> struct magn_3d_state *st)
>> {
>> - int ret;
>> + int ret = 0;
>> int i;
>> + int attr_count = 0;
>> +
>> + /* Scan for each usage attribute supported */
>> + for (i = 0; i < MAGN_3D_CHANNEL_MAX; i++) {
>> + u32 address = magn_3d_addresses[i];
>>
>> - for (i = 0; i <= CHANNEL_SCAN_INDEX_Z; ++i) {
>> + /* Check if usage attribute exists in the sensor hub
>> device */
>> ret = sensor_hub_input_get_attribute_info(hsdev,
>> - HID_INPUT_REPORT,
>> - usage_id,
>> - HID_USAGE_SENSOR_ORIENT_MAGN_FLUX_X_AXIS +
>> i,
>> - &st->magn[CHANNEL_SCAN_INDEX_X + i]);
>> - if (ret < 0)
>> - break;
>> - magn_3d_adjust_channel_bit_mask(channels,
>> - CHANNEL_SCAN_INDEX_X + i,
>> - st->magn[CHANNEL_SCAN_INDEX_X + i].size);
>
> I would have preferred you kept the indenting the same as before. That would
> make it more obvious what changed.
>
>> + HID_INPUT_REPORT,
>> + usage_id,
>> + address,
>> + &(st->magn[i]));
>> + if (!ret)
>> + attr_count++;
>> }
>> - dev_dbg(&pdev->dev, "magn_3d %x:%x, %x:%x, %x:%x\n",
>> +
>> + dev_dbg(&pdev->dev, "magn_3d Found %d usage attributes\n",
>> + attr_count);
>> + dev_dbg(&pdev->dev, "magn_3d X: %x:%x Y: %x:%x Z: %x:%x\n",
>> st->magn[0].index,
>> st->magn[0].report_id,
>> st->magn[1].index, st->magn[1].report_id,
>> st->magn[2].index, st->magn[2].report_id);
>>
>> + if (attr_count > 0)
>> + ret = 0;
>
> This would suggest to me that you want to rename the ret above (used
> to indicate if a channel is there) as something more specific so you
> don't end up appearing to squash and error here...
>

The ret value above needs to be zeroed out as it is used to break out
of the for loop when scanning for usage attributes.
I will use a different variable name perhaps to distinguish the two.
>> + else
>> + return -EINVAL;
>
> Again your spacing is messed up. Please fix.
>
>> +
>> + /* Setup IIO channel array */
>> + *channels = devm_kcalloc(&pdev->dev, attr_count,
>> +
>
> The resulting indenting here is a complete mess. Please fix.
>
>
> sizeof(struct iio_chan_spec),
>>
>> +
>> GFP_KERNEL);
>> + if (!*channels) {
>> + dev_err(&pdev->dev, "failed to allocate space for iio
>> channels\n");
>> + return -ENOMEM;
>> + }
>> +
>> + st->iio_val = devm_kcalloc(&pdev->dev, attr_count,
>> +
>> sizeof(u32),
>> +
>> GFP_KERNEL);
>> + if (!st->iio_val) {
>> + dev_err(&pdev->dev, "failed to allocate space for iio
>> values array\n");
>> + return -ENOMEM;
>> + }
>> +
>> + for (i = 0, *chan_count = 0;
>> + i < MAGN_3D_CHANNEL_MAX && *chan_count < attr_count;
>> + i++)
>> + {
>> + if (st->magn[i].index >= 0) {
>> + /* Setup IIO channel struct */
>> + *channels[*chan_count] = magn_3d_channels[i];
>> +
>> + st->magn_val_addr[i] =
>> &(st->iio_val[*chan_count]);
>> + magn_3d_adjust_channel_bit_mask(*channels,
>> *chan_count, st->magn[i].size);
>
> The above should be wrapped appropriately.
>
>> + (*chan_count)++;
>> + }
>> + }
>> +
>> st->scale_precision = hid_sensor_format_scale(
>> HID_USAGE_SENSOR_COMPASS_3D,
>> &st->magn[CHANNEL_SCAN_INDEX_X],
>> @@ -311,6 +359,7 @@ static int hid_magn_3d_probe(struct platform_device
>> *pdev)
>> struct magn_3d_state *magn_state;
>> struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
>> struct iio_chan_spec *channels;
>> + int chan_count = 0;
>>
>> indio_dev = devm_iio_device_alloc(&pdev->dev,
>> sizeof(struct magn_3d_state));
>> @@ -331,22 +380,15 @@ static int hid_magn_3d_probe(struct platform_device
>> *pdev)
>> return ret;
>> }
>>
>> - channels = kmemdup(magn_3d_channels, sizeof(magn_3d_channels),
>> - GFP_KERNEL);
>> - if (!channels) {
>> - dev_err(&pdev->dev, "failed to duplicate channels\n");
>> - return -ENOMEM;
>> - }
>> -
>> - ret = magn_3d_parse_report(pdev, hsdev, channels,
>> - HID_USAGE_SENSOR_COMPASS_3D, magn_state);
>> + ret = magn_3d_parse_report(pdev, hsdev, &channels,
>> + &chan_count, HID_USAGE_SENSOR_COMPASS_3D,
>> magn_state);
>> if (ret) {
>> dev_err(&pdev->dev, "failed to setup attributes\n");
>> - goto error_free_dev_mem;
>> + return ret;
>> }
>>
>> indio_dev->channels = channels;
>> - indio_dev->num_channels = ARRAY_SIZE(magn_3d_channels);
>> + indio_dev->num_channels = chan_count;
>> indio_dev->dev.parent = &pdev->dev;
>> indio_dev->info = &magn_3d_info;
>> indio_dev->name = name;
>> @@ -356,7 +398,7 @@ static int hid_magn_3d_probe(struct platform_device
>> *pdev)
>> NULL, NULL);
>> if (ret) {
>> dev_err(&pdev->dev, "failed to initialize trigger
>> buffer\n");
>> - goto error_free_dev_mem;
>> + return ret;
>> }
>> atomic_set(&magn_state->common_attributes.data_ready, 0);
>> ret = hid_sensor_setup_trigger(indio_dev, name,
>> @@ -390,8 +432,6 @@ error_remove_trigger:
>> hid_sensor_remove_trigger(&magn_state->common_attributes);
>> error_unreg_buffer_funcs:
>> iio_triggered_buffer_cleanup(indio_dev);
>> -error_free_dev_mem:
>> - kfree(indio_dev->channels);
>> return ret;
>> }
>>
>> @@ -406,7 +446,6 @@ static int hid_magn_3d_remove(struct platform_device
>> *pdev)
>> iio_device_unregister(indio_dev);
>> hid_sensor_remove_trigger(&magn_state->common_attributes);
>> iio_triggered_buffer_cleanup(indio_dev);
>> - kfree(indio_dev->channels);
>>
>> return 0;
>> }
>>
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/