Re: [PATCH v2 3/4] hwmon/ltc2990: Add platform_data support

[Guenter Roeck]

On 8/13/19 1:27 AM, Geert Uytterhoeven wrote:
> Hi GÃnter,
>
> On Tue, Aug 13, 2019 at 10:02 AM Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
> > On Tue, Aug 13, 2019 at 01:52:36AM +0200, Max Staudt wrote:
> > > This allows code using i2c_new_device() to specify a measurement mode.
> > >
> > > Signed-off-by: Max Staudt <max@xxxxxxxxx>
> > > Reviewed-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
> > > ---
> > >   drivers/hwmon/ltc2990.c               |  9 +++++++++
> > >   include/linux/platform_data/ltc2990.h | 11 +++++++++++
> > >   2 files changed, 20 insertions(+)
> > >   create mode 100644 include/linux/platform_data/ltc2990.h
> > >
> > > diff --git a/drivers/hwmon/ltc2990.c b/drivers/hwmon/ltc2990.c
> > > index f9431ad43..f19b9c50c 100644
> > > --- a/drivers/hwmon/ltc2990.c
> > > +++ b/drivers/hwmon/ltc2990.c
> > > @@ -14,6 +14,7 @@
> > >   #include <linux/kernel.h>
> > >   #include <linux/module.h>
> > >   #include <linux/of.h>
> > > +#include <linux/platform_data/ltc2990.h>
> > >
> > >   #define LTC2990_STATUS       0x00
> > >   #define LTC2990_CONTROL      0x01
> > > @@ -206,6 +207,7 @@ static int ltc2990_i2c_probe(struct i2c_client *i2c,
> > >        int ret;
> > >        struct device *hwmon_dev;
> > >        struct ltc2990_data *data;
> > > +     struct ltc2990_platform_data *pdata = dev_get_platdata(&i2c->dev);
> > >        struct device_node *of_node = i2c->dev.of_node;
> > >
> > >        if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA |
> > > @@ -227,6 +229,13 @@ static int ltc2990_i2c_probe(struct i2c_client *i2c,
> > >                if (data->mode[0] & ~LTC2990_MODE0_MASK ||
> > >                    data->mode[1] & ~LTC2990_MODE1_MASK)
> > >                        return -EINVAL;
> > > +     } else if (pdata) {
> > > +             data->mode[0] = pdata->meas_mode[0];
> > > +             data->mode[1] = pdata->meas_mode[1];
> > > +
> > > +             if (data->mode[0] & ~LTC2990_MODE0_MASK ||
> > > +                 data->mode[1] & ~LTC2990_MODE1_MASK)
> > > +                     return -EINVAL;
> >
> > I would prefer if the driver was modified to accept device
> > properties, and if those were set using the appropriate
> > fwnode function. Any reason for not doing that ?
>
> That was my first thought as well, but isn't that limited to DT and ACPI
> properties (for now)?

tcpm and, for example, the wcove driver don't seem to have a problem using
it, I don't see acpi involved there. Also, the code resides in the core driver
code and is always enabled unless I am missing something. What am I missing ?

Guenter