[PATCH] pinctrl: pinctrl-imx: don't use invalid value of conf_reg

[Uwe Kleine-König]

On Tue, Feb 03, 2015 at 02:01:09PM +0100, Linus Walleij wrote:
> On Tue, Jan 27, 2015 at 11:50 PM, Uwe Kleine-König
> <u.kleine-koenig at pengutronix.de> wrote:
> 
> > The right check for conf_reg to be invalid it testing against -1 not 0
> > as is done in the rest of the driver.
> >
> > This fixes an oops that can be triggered by:
> >
> >         cat /sys/kernel/debug/pinctrl/43fac000.iomuxc/*
> >
> > Fixes: ae75ff814538 ("pinctrl: pinctrl-imx: add imx pinctrl core driver")
> > Signed-off-by: Uwe Kleine-König <u.kleine-koenig at pengutronix.de>
> 
> Patch applied.
> 
> But...
> 
> > -       if (!pin_reg || !pin_reg->conf_reg) {
> > +       if (!pin_reg || pin_reg->conf_reg == -1) {
> 
> I can see that the other code checks for -1 in this variable.
> But where is conf_reg ever set to -1?
> 
> freescale]$ git grep "\-1"
> pinctrl-imx.c:          if (pin_reg->mux_reg == -1) {
> pinctrl-imx.c:  if (pin_reg->mux_reg == -1)
> pinctrl-imx.c:  if (pin_reg->mux_reg == -1)
> pinctrl-imx.c:  if (pin_reg->conf_reg == -1) {
> pinctrl-imx.c:  if (pin_reg->conf_reg == -1) {
> pinctrl-imx.c:  if (!pin_reg || pin_reg->conf_reg == -1) {
Uah, ugly. This member gets -1 by means of:

	memset(info->pin_regs, 0xff, sizeof(*info->pin_regs) * info->npins);

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
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