Re: [PATCH 2/2] iio: Add AS3935 lightning sensor support

From: Marek Vasut
Date: Sat Feb 01 2014 - 00:28:52 EST


On Saturday, February 01, 2014 at 06:03:22 AM, Matt Ranostay wrote:
> Duly noted. Will be fixed in the next rev... mutexs are pointless as you
> say.. only corner case would be if you were changing gain_boost and a event
> came in at the same time. But that wouldn't harm anything except slightly
> delay the gain_boost being updated by some x microseconds.

Please stop top-posting ;-)

btw I think you might need a mutex around the entire:

+static void calibrate_as3935(struct as3935_state *st)
+{
+ /* mask disturber interrupt bit */
+ as3935_write(st, AS3935_INT, 1 << 5);
+
+ as3935_write(st, AS3935_CALIBRATE, 0x96);
+ as3935_write(st, AS3935_TUNE_CAP, 1 << 5 | st->tune_cap);
+
+ mdelay(2);
+ as3935_write(st, AS3935_TUNE_CAP, st->tune_cap);
+}

and similar functions where you do a bunch of register accesses. This is because
you probably want to protect them against concurent execution so the chip won't
be confused if a user were to poke something via SYSFS twice.

Best regards,
Marek Vasut
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