Hi Linus, I realize I never replied to this review. On Thu, 26 Apr 2018 10:44:26 +0200 Linus Walleij <linus.walleij@xxxxxxxxxx> wrote: > On Fri, Mar 30, 2018 at 9:47 AM, Boris Brezillon > <boris.brezillon@xxxxxxxxxxx> wrote: > > > Add a driver for Cadence I3C GPIO expander. > > > > Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxx> > > This is pretty much OK, and I don't want to raise the bar > even higher for you to get this code into the kernel, so: > Acked-by: Linus Walleij <linus.walleij@xxxxxxxxxx> Thanks. > > The following is an observation for future improvement: > > > +static int cdns_i3c_gpio_read_reg(struct cdns_i3c_gpio *gpioc, u8 reg, > > + u8 *val) > > +{ > > + struct i3c_priv_xfer xfers[] = { > > + { > > + .len = sizeof(reg), > > + .data.out = ®, > > + }, > > + { > > + .rnw = true, > > + .len = sizeof(*val), > > + .data.in = val, > > + }, > > + }; > > + > > + return i3c_device_do_priv_xfers(gpioc->i3cdev, xfers, > > + ARRAY_SIZE(xfers)); > > +} > > + > > +static int cdns_i3c_gpio_write_reg(struct cdns_i3c_gpio *gpioc, u8 reg, > > + u8 val) > > +{ > > + struct i3c_priv_xfer xfers[] = { > > + { > > + .len = sizeof(reg), > > + .data.out = ®, > > + }, > > + { > > + .len = sizeof(val), > > + .data.out = &val, > > + }, > > + }; > > + > > + return i3c_device_do_priv_xfers(gpioc->i3cdev, xfers, > > + ARRAY_SIZE(xfers)); > > +} > > This is starting to resemble > drivers/base/regmap/regmap-i2c.c > > Maybe we should very quickly add regmap-i3c.c as this > infrastructre has had a great positive effect on may kernel > subsystems. Yes I considered that too, I was just waiting for at least one other user before adding this regmap-i3c implementation. > > > +static int cdns_i3c_gpio_get_direction(struct gpio_chip *g, unsigned offset) > > +{ > > + struct cdns_i3c_gpio *gpioc = gpioc_to_cdns_gpioc(g); > > + > > + return gpioc->dir & BIT(offset); > > I would: > > return !!(gpioc->dir & BIT(offset)); > > So you clamp it to bit 0. Will fix that in my v5. Thanks for your review. Boris -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html