Re: [PATCH] iio: accel: adxl380: clamp FIFO sample count
"Shengzhuo Wei" <[email protected]>
| Newsgroups | org.kernel.vger.linux-iio,org.kernel.vger.linux-kernel,org.kernel.vger.stable |
|---|---|
| Message-ID | <anlcOa5tkTUN9EQr@nobug> |
在 2026-08-10 00:28,Jonathan Cameron 写道:
> > Fixes: df36de13677a ("iio: accel: add ADXL380 driver")
>
> In my opinion at least, these are not fixes. In general we don't expect
> drivers to be hardened against broken hardware returning out of spec
> values. I don't mind taking simple cases though that don't complicate
> the code much and if anything make it a little easier to follow,
> but I don't currently see any reason to mark them as a fix.
>
> So drop that tag for v2.
>
Hi Jonathan,
Thanks. Understood — I'll drop the Fixes tag and stop clamping.
> This is papering over what we think is a hardware failure. Unless I am
> missing something the device is returning garbage, otherwise we are in
> range and this has no affect. We have no idea how much data there is
> if we get a value outside the expected range.
>
> As such I'd expect an error print and probably no attempt to carry
> on reading as we have no idea what happened.
For v2 I'll treat an out-of-range count as a hardware error,
log it, and skip the read rather than carrying on:
ret = adxl380_get_fifo_entries(st, &fifo_entries);
if (ret)
return IRQ_HANDLED;
if (fifo_entries > ADXL380_FIFO_SAMPLES) {
dev_err_ratelimited(st->dev,
"invalid FIFO entry count %u (max %lu)\n",
fifo_entries, ADXL380_FIFO_SAMPLES);
return IRQ_HANDLED;
}
fifo_entries = rounddown(fifo_entries, st->fifo_set_size);
ret = regmap_noinc_read(st->regmap, ADXL380_FIFO_DATA, &st->fifo_buf,
sizeof(*st->fifo_buf) * fifo_entries);
Same for adxl367 (push_fifo_data: dev_err_ratelimited and return true
without reading the FIFO).
I'll send the two as a single series with a cover letter, no Fixes tags.
Let me know if this looks OK to you, or if you'd change anything, and
I'll send the v2 series.
Best regards,
Shengzhuo Wei