Re: [PATCH v2 3/3] power: bq27xxx: add support for NVRAM R/W access

[Sebastian Reichel <sre-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>]

[-- Attachment #1: Type: text/plain, Size: 1876 bytes --]

On Wed, Jan 04, 2017 at 06:10:07PM -0800, Matt Ranostay wrote:
> Initial support for access and modification of the non-volatile regions
> of the bq27425 fuel gauge DesignEnergy, DesignCapacity, and
> TerminateVoltage settings.
> 
> This is intended for fine tuning the fuel gauge state machine for the
> respective battery specifications.
> 
> Cc: Sebastian Reichel <sre-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
> Signed-off-by: Matt Ranostay <matt-sk+viVC6FLCDq+mSdOJa79kegs52MxvZ@public.gmane.org>
> ---
>  drivers/power/supply/bq27xxx_battery_i2c.c | 335 +++++++++++++++++++++++++++++
>  include/linux/power/bq27xxx_battery.h      |   4 +
>  2 files changed, 339 insertions(+)

I only skipped over this one, as the changed DT binding requires
quite some changes in this patch anyways. Here are a couple of
comments how I would like to see this implemented:

Add a patch for the power-supply core, which implements a
structure for the battery info. Something like this:

struct power_supply_battery_info {
    uint32 energy; /* µWh */
    uint32 power;  /* µAh */
    uint32 nominal_voltage; /* µV */
    /* ... */
};

And a function in the core framework, which gets the information
from DT. The function itself should *not* be DT specific, so that
ACPI/platformdata/whatever support can be added later without
modifying every single driver.

static struct power_supply_battery_info*
power_supply_get_battery_info(struct power_supply *psy) {
    if (psy->dt) {
        /* get battery phandle or return -ENXIO */
        /* fill and return struct */
    }

    return -ENOTSUP;
}

Then call power_supply_get_battery_info() during bq27xxx probe and
use the struct to initialize the registers. Also I expect that
functionality in bq27xxx_battery.c instead of bq27xxx_battery_i2c.c,
since it's not I²C specific.

-- Sebastian

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]