On 08/01/2017 11:41 AM, Andy Shevchenko wrote:
On Tue, 2017-08-01 at 11:21 -0500, David Lechner wrote:
On 08/01/2017 10:45 AM, Andy Shevchenko wrote:
+ /* Use hard coded value for reference voltage in ACPI
case */
+ if (ACPI_COMPANION(&spi->dev))
+ st->vref_mv = TI_ADS7950_VA_MV_ACPI_DEFAULT;
Instead of checking or ACPI, you could just say "if we have a
dummy
regulator, then use the default value".
Agreed. Sounds sensible to me. Hopefully in DT people will
provide the right regulator, but chances are this won't
always happen.
There is no call like
regulator_is_dummy()
(and, looking into the code of regulator framework, can't be)
Can you elaborate a bit, maybe I'm missing something obvious?
I haven't tested this, but shouldn't regulator_get_voltage() return
an
error for a dummy regulator? You could use this as your test.
While it would work it's very fragile.
_regulator_get_voltage() will return error code even for normal
regulators if something happened there. And user gets an impression that
everything is okay while it's not.
So, I wouldn't go this way.
static int ti_ads7950_get_range(struct ti_ads7950_state *st)
{
int vref;
vref = regulator_get_voltage(st->reg);
if (vref < 0)
- return vref;
+ vref = 2500000;
vref /= 1000;
if (st->settings & TI_ADS7950_CR_RANGE_5V)
vref *= 2;
return vref;
}
OK. There is also devm_regulator_get_optional(). This will return
ERR_PTR(-ENODEV) instead of a dummy regulator. Then you could add a
check for this error and set st->reg = NULL if we get -ENODEV. Make the
enable and disable conditional. And use the default voltage if we don't
have a regulator.
But this is probably even messier than the original ACPI patch. :-/
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