lkml.org 
[lkml]   [2007]   [Dec]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH 1/5] power: RFC: introduce a new power API
    On Mon, Dec 17, 2007 at 02:41:39AM -0500, Andres Salomon wrote:
    [...]
    > > > On Sun, 2007-12-16 at 21:24 -0500, Andres Salomon wrote:
    > > > > This API has the power_supply drivers device their own device_attribute
    > > > > list; I find this to be a lot more flexible and cleaner.
    > >
    > > I don't see how this is more flexible and cleaner. See below.
    > >
    > > > > For example,
    > > > > rather than having a function with a huge switch statement (as olpc_battery
    > > > > currently has), we have separate callback functions.
    > >
    > > Is this an improvement? Look into ds2760_battery.c. I scared to
    > > imagine what it will look like after conversion.
    >
    > Why? It would not look bad after conversion. Basically:
    >
    > static ssize_t ds2760_battery_get_status(struct device *dev,
    > struct device_attribute *attr, char *buf)
    > {
    > struct ds2760_device_info *di = to_ds2760_device_info(psy);
    > return power_supply_status_str(di->charge_status, buf);
    > }
    > static ssize_t ds2760_battery_get_voltage_now(struct device *dev,
    > struct device_attribute *attr, char *buf)
    > {
    > struct ds2760_device_info *di = to_ds2760_device_info(psy);
    > ds2760_battery_read_status(di);
    > return sprintf(buf, "%d\n", di->voltage_uV);
    > }
    >
    > ....an so on.
    >
    > If I wanted to get really clever, I could do:
    >
    > #define DS2760_CALLBACK(name, fmt, var) \
    > static ssize_t ds2760_battery_get_##name(struct device *dev, \
    > struct device_attribute *attr, char *buf) \
    > { \
    > struct ds2760_device_info *di = to_ds2760_device_info(psy); \
    > ds2760_battery_read_status(di); \
    > return sprintf(buf, fmt, var); \
    > }
    >
    > DS2760_CALLBACK(voltage_now, "%d\n", di->voltage_uV)
    > DS2760_CALLBACK(current_now, "%d\n", di->current_uA)
    >
    > etc.. but, I'm not trying to compress lines of code, I'm trying
    > to ensure things are readable.

    Hehe, look: http://lkml.org/lkml/2007/4/11/397

    These macros are indeed what I've tried to avoid, dozen open-coded
    similar functions not a good option either. I also tried to avoid
    "function per property" stuff...

    [lots of sense snipped]

    I see your point now. Basically, now I'm encourage to think just one
    more time: is there third (better) option in addition to current and
    this? I still hope there is some not obvious, but elegant solution.
    If there isn't, I'm ready to surrender and will help with everything
    I can.


    Thanks!

    --
    Anton Vorontsov
    email: cbou@mail.ru
    backup email: ya-cbou@yandex.ru
    irc://irc.freenode.net/bd2


    \
     
     \ /
      Last update: 2007-12-17 12:25    [W:0.025 / U:0.164 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site