Re: [PATCH V2 2/2] Input: misc: introduce palmas-pwrbutton

From: Nishanth Menon
Date: Thu Aug 21 2014 - 13:37:52 EST


On 12:32-20140821, Murphy, Dan wrote:
> On 08/21/2014 12:19 PM, Menon, Nishanth wrote:
> > On 08/21/2014 11:59 AM, Murphy, Dan wrote:
> > [...]
> > Ooops.. missed answering one addition statement:
> >
> >>> + of_property_read_u32(np, "ti,palmas-long-press-seconds", &val);
> >>
> >> Probably should check the return to make sure the value exists and that is is
> >> within an expected range.
> > It is an optional parameter and may not exist in dt. when it does
> > exist, the logic tries to do a best match (this is the for loop in the
> > logic just below).
> >
>
> The issue is val might be returned as a negative which will then proceed to
> set the config->long_press_time_val to the lowest time value which then overrides
> your initial setting of config->long_press_time_val = ARRAY_SIZE(lpk_times) - 1;
>

Does the following as a replacement look OK? if yes, I can incorporate
as part of v3 of this series.
/**
* palmas_pwron_params_ofinit() - device tree parameter parser
* @dev: palmas button device
* @config: configuration params that this fills up
*/
static void palmas_pwron_params_ofinit(struct device *dev,
struct palmas_pwron_config *config)
{
struct device_node *np;
u32 val;
int i, ret;
u8 lpk_times[] = { 6, 8, 10, 12 };
int pwr_on_deb_ms[] = { 15, 100, 500, 1000 };

/* Handle cases where device node based configuration is not present */
if (!of_have_populated_dt())
return;
np = of_node_get(dev->of_node);
if (!np)
return;

/* Default config parameters - least debounce, max long key press */
config->pwron_debounce_val = 0;
config->long_press_time_val = ARRAY_SIZE(lpk_times) - 1;

ret = of_property_read_u32(np, "ti,palmas-long-press-seconds", &val);
if (ret)
goto skip_lpk;
for (i = 0; i < ARRAY_SIZE(lpk_times); i++) {
if (val <= lpk_times[i]) {
config->long_press_time_val = i;
break;
}
}

skip_lpk:
ret = of_property_read_u32(np, "ti,palmas-pwron-debounce-milli-seconds",
&val);
if (ret)
goto skip_debounce;
for (i = 0; i < ARRAY_SIZE(pwr_on_deb_ms); i++) {
if (val <= pwr_on_deb_ms[i]) {
config->pwron_debounce_val = i;
break;
}
}

skip_debounce:
dev_info(dev, "h/w controlled shutdown duration=%d seconds\n",
lpk_times[config->long_press_time_val]);

of_node_put(np);
}
--
Regards,
Nishanth Menon
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