On Nov 14, 2007 12:18 PM, David Brownell <[EMAIL PROTECTED]> wrote: > On Tuesday 13 November 2007, eric miao wrote: > > Here comes the point of "struct gpio_desc" > > > > Subject: [PATCH 3/5] use a per GPIO "struct gpio_desc" and chain > > "gpio_chip" to a list > > I see what it does, but don't see the "why" ... surely > you can come up with a one sentence description of why > this would be better? > > And I'd been so glad to *get rid of* that list, too.
I'll be happy too. > > > > +struct gpio_desc { > > + struct gpio_chip *chip; > > +}; > > + > > > -/* gpio_lock protects modification to the table of chips and to > > - * gpio_chip->requested. If a gpio is requested, its gpio_chip > > - * is not removable. > > - */ > > But it still protects data. Don't remove documentation for > what locks protect ... update it! Otherwise someonels going > to come by and make a change which breaks the locking model. > Usually in some subtle (hard-to-debug) way. I'd prefer to name it "gpio_desc_lock" instead, which is self-explanatory and thus requires no comment at all > > > > > - for (id = 0; id < ARRAY_SIZE(chips); id++) { > > - chip = chips[id]; > > - if (!chip) > > - continue; > > - > > + list_for_each_entry(chip, &gpio_chip_list, node) { > > seq_printf(s, "%sGPIOs %d-%d, %s%s:\n", > > started ? "\n" : "", > > chip->base, chip->base + chip->ngpio - 1, > > Note that this now produces the debug info in a relatively > random order ... ordered by registration rather than anything > useful, and hence awkward to read. > > It'd be better if you just scanned your new gpio_desc[] > table in numeric order, and start a new section whenever > you find a new gpio_chip. > > That'd get rid of that otherwise-useless list, too. > absolutely, you get the same feeling of mine and since this is for illustration purpose only, I don't want more patches to fix this... > - Dave > -- Cheers - eric - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/