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

[Geert Uytterhoeven]

Hi GÃnter,

On Tue, Aug 13, 2019 at 3:27 PM Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
> On 8/13/19 1:27 AM, Geert Uytterhoeven wrote:
> > 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

Cool, just discovered that, following your other fwnode_create_software_node()
pointer...

> code and is always enabled unless I am missing something. What am I missing ?

You're missing that I'm not up-to-date w.r.t. the latest fwnode properties
development ;-)

Thanks a lot!

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds