On Fri, 2023-08-18 at 14:19 +0300, Andy Shevchenko wrote:
> On Thu, Aug 17, 2023 at 11:05:21PM +0200, Angel Iglesias wrote:
> > Improve device detection in certain chip families known to have various
> > chip ids.
>
> ...
>
> > + ret = -EINVAL;
>
> Why do you need this...
>
> > + for (i = 0; i < data->chip_info->num_chip_id; i++) {
> > + if (chip_id == data->chip_info->chip_id[i]) {
>
> > + ret = 0;
>
> ..and this...
>
> > + break;
> > + }
> > + }
>
> > + if (ret) {
>
> ...and this?
>
> You can simply do
>
> for (i = 0; i < data->chip_info->num_chip_id; i++) {
> if (chip_id == data->chip_info->chip_id[i])
> break;
> }
> if (i < data->chip_info->num_chip_id) {
>
Got it, much cleaner also.
> ...
>
> > + // 0x<id>, so four chars per number plus one space + ENDL
> > + size_t nbuf = 5*data->chip_info->num_chip_id*sizeof(char);
>
> Besides lack of spaces...
>
> > + char *buf = kmalloc(nbuf, GFP_KERNEL);
>
> ...this at least should be kmalloc_array() and on top maybe something from
> overflow.h will be needed.
Sure, I'll give a look. I didn't want to do string manipulations on a kernel
driver but couldn't found a way to log the error meaningfully in one entry.
> > + if (!buf)
> > + return ret;
> > +
> > + for (i = 0; i < data->chip_info->num_chip_id; i++)
> > + snprintf(&buf[i*5], nbuf, "0x%x ", data->chip_info-
> > >chip_id[i]);
> > + buf[nbuf-1] = '\0';
> > +
> > + dev_err(dev, "bad chip id: expected [ %s ] got 0x%x\n", buf,
> > chip_id);
> > + kfree(buf);
> > + return ret;
> > }
>
> ...
>
> > - const unsigned int chip_id;
>
> Yeah, this const makes a little sense...
>
> > + const unsigned int *chip_id;
>
> ...but not this :-)
Isn't the same case as "const struct iio_chan_spec *channels" or "const int
*oversampling_temp_avail". I thoght that this meant a pointer to a constant
integer. On bmp280-core I declare the arrays with the modifiers static const.
> What I'm wondering is why it's int and not u8 / u16
> (as it seems only a byte value there).
Yeah, can be u8, as the reg width is 1 byte and this IDs are stored on one reg.
I just carried over the int type from previous versions, but it's just wasting
space :/
>
> > + int num_chip_id;
>
> unsigned.
>
Thanks for your time!
Kind regards,
Angel
