Re: [PATCH v3 03/14] ASoC: SOF: Add driver debug support.

[Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>]

>> +	if (count > size - pos)
>> +		count = size - pos;
> max() / min()
ok
>
>> +	/* intermediate buffer size must be u32 multiple */
>> +	size = (count + 3) & ~3;
> Hmm, don't we have something like round_up()?
yes, round_up (count, 4) would work.
>
>> +	dfse->dfsentry = debugfs_create_file(name, 0444, sdev->debugfs_root,
>> +					     dfse, &sof_dfs_fops);
>> +	if (!dfse->dfsentry) {
>> +		dev_err(sdev->dev, "error: cannot create debugfs entry.\n");
>> +		return -ENODEV;
>> +	}
> We shouldn't rely on debugfs files.
> Thus, error checking needs to be removed.
>
> Something like
>
> void ()
> {
> struct dentry *d;
>
> d = debugfs_...();
> if (!d)
> 	dev_err();
> }

You lost me on this one. The main purpose of this return -ENODEV is to 
avoid adding more entries if one item failed. It's not different from 
what our estimeed colleagues did in skl-debug.c


>
>
>> +	dfse->dfsentry = debugfs_create_file(name, 0444, sdev->debugfs_root,
>> +					     dfse, &sof_dfs_fops);
>> +	if (!dfse->dfsentry) {
>> +		dev_err(sdev->dev, "error: cannot create debugfs entry.\n");
>> +		return -ENODEV;
>> +	}
> Ditto.
>
>> +	sdev->debugfs_root = debugfs_create_dir("sof", NULL);
>> +	if (IS_ERR_OR_NULL(sdev->debugfs_root)) {
>> +		dev_err(sdev->dev, "error: failed to create debugfs directory\n");
>> +		return -EINVAL;
>> +	}
>> +
>> +	/* create debugFS files for platform specific MMIO/DSP memories */
>> +	for (i = 0; i < ops->debug_map_count; i++) {
>> +		map = &ops->debug_map[i];
>> +
>> +		err = snd_sof_debugfs_io_create_item(sdev, sdev->bar[map->bar] +
>> +						  map->offset, map->size,
>> +						  map->name);
>> +		if (err < 0)
>> +			dev_err(sdev->dev, "error: cannot create debugfs for %s\n",
>> +				map->name);
> Ditto (error message dups above).
>
>> +	}
>> +
>> +	return err;

or maybe that's the issue, we shouldn't return an error on the init 
proper, but I see nothing wrong in stopping when things go south.


>> +}
>> +EXPORT_SYMBOL(snd_sof_dbg_init);