Re: [PATCH 3/3] usb: phy: msm: use ASSIGN_*_PM_OPS variants

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Fri, Feb 28, 2014 at 09:48:08AM +0100, Ulf Hansson wrote:
> On 28 February 2014 00:44, Greg Kroah-Hartman
> <gregkh@linuxfoundation.org> wrote:
> > On Thu, Feb 27, 2014 at 03:41:31PM -0800, David Cohen wrote:
> >> On Thu, Feb 27, 2014 at 11:03:24AM -0800, Greg Kroah-Hartman wrote:
> >> > On Tue, Feb 25, 2014 at 12:33:36PM -0600, Felipe Balbi wrote:
> >> > > Hi,
> >> > >
> >> > > On Mon, Feb 24, 2014 at 11:08:27AM -0600, Josh Cartwright wrote:
> >> > > > Use ASSIGN_SYSTEM_SLEEP_PM_OPS and ASSIGN_RUNTIME_PM_OPS in the
> >> > > > initializer for msm_otg_dev_pm_ops.  Doing so allows us to eliminate
> >> > > > preprocessor conditionals around the specified callbacks.
> >> > > >
> >> > > > Signed-off-by: Josh Cartwright <joshc@codeaurora.org>
> >> > > > ---
> >> > > >  drivers/usb/phy/phy-msm-usb.c | 13 +++----------
> >> > > >  1 file changed, 3 insertions(+), 10 deletions(-)
> >> > > >
> >> > > > diff --git a/drivers/usb/phy/phy-msm-usb.c b/drivers/usb/phy/phy-msm-usb.c
> >> > > > index 5b37b81..c04f2e3 100644
> >> > > > --- a/drivers/usb/phy/phy-msm-usb.c
> >> > > > +++ b/drivers/usb/phy/phy-msm-usb.c
> >> > > > @@ -414,8 +414,6 @@ static int msm_otg_reset(struct usb_phy *phy)
> >> > > >  #define PHY_SUSPEND_TIMEOUT_USEC       (500 * 1000)
> >> > > >  #define PHY_RESUME_TIMEOUT_USEC        (100 * 1000)
> >> > > >
> >> > > > -#ifdef CONFIG_PM
> >> > > > -
> >> > > >  #define USB_PHY_SUSP_DIG_VOL  500000
> >> > > >  static int msm_hsusb_config_vddcx(int high)
> >> > > >  {
> >> > > > @@ -609,7 +607,6 @@ skip_phy_resume:
> >> > > >
> >> > > >         return 0;
> >> > > >  }
> >> > > > -#endif
> >> > > >
> >> > > >  static void msm_otg_notify_charger(struct msm_otg *motg, unsigned mA)
> >> > > >  {
> >> > > > @@ -1664,7 +1661,6 @@ static int msm_otg_remove(struct platform_device *pdev)
> >> > > >         return 0;
> >> > > >  }
> >> > > >
> >> > > > -#ifdef CONFIG_PM_RUNTIME
> >> > > >  static int msm_otg_runtime_idle(struct device *dev)
> >> > > >  {
> >> > > >         struct msm_otg *motg = dev_get_drvdata(dev);
> >> > > > @@ -1699,9 +1695,7 @@ static int msm_otg_runtime_resume(struct device *dev)
> >> > > >         dev_dbg(dev, "OTG runtime resume\n");
> >> > > >         return msm_otg_resume(motg);
> >> > > >  }
> >> > > > -#endif
> >> > > >
> >> > > > -#ifdef CONFIG_PM_SLEEP
> >> > > >  static int msm_otg_pm_suspend(struct device *dev)
> >> > > >  {
> >> > > >         struct msm_otg *motg = dev_get_drvdata(dev);
> >> > > > @@ -1731,12 +1725,11 @@ static int msm_otg_pm_resume(struct device *dev)
> >> > > >
> >> > > >         return 0;
> >> > > >  }
> >> > > > -#endif
> >> > > >
> >> > > >  static const struct dev_pm_ops msm_otg_dev_pm_ops = {
> >> > > > -       SET_SYSTEM_SLEEP_PM_OPS(msm_otg_pm_suspend, msm_otg_pm_resume)
> >> > > > -       SET_RUNTIME_PM_OPS(msm_otg_runtime_suspend, msm_otg_runtime_resume,
> >> > > > -                               msm_otg_runtime_idle)
> >> > > > +       ASSIGN_SYSTEM_SLEEP_PM_OPS(msm_otg_pm_suspend, msm_otg_pm_resume)
> >> > > > +       ASSIGN_RUNTIME_PM_OPS(msm_otg_runtime_suspend, msm_otg_runtime_resume,
> >> > > > +                             msm_otg_runtime_idle)
> >> > >
> >> > > if the patch introducing assign_if() gets accepted, I'm ok with this
> >> > > patch.
> >> >
> >> > I can't take that patch at this point in time, it's just too ugly...
> >> >
> >> > As are those crazy SET_SYSTEM_SLEEP_PM_OPS() macros, ick, who made those
> >> > things?
> >> >
> >> > What language are we trying to program in here people?
> >>
> >> Since we're discussing this topic here, I'd like point my RFC which gets
> >> rid of same ifdeffery in a different way:
> >> http://lkml.org/lkml/2013/12/13/4
> >
> > Again, why can't we just always define these fields in the structure,
> > then we don't need any crazy, complicated mess for assigning the
> > function pointers?
> >
> > Again, the odds that this config option is ever disabled in "real"
> > systems is so low these days, I have half a mind just to rip it out
> > entirely as the amount of work spent on compiler warnings and the like
> > in this area has proably offset any power savings the code was supposed
> > to save on systems :(
> 
> Your point is certainly valid. I suppose the footprint of the kernel
> is nothing we should bother about? We have other solutions for that,
> right?

What does the "footprint of the kernel" have to do with an option that
everyone enables as they want/need the functionality?  You are only
talking about saving size for systems that do not exist.  Do you know of
any commen system that cares about size and yet not power that would be
affected by this change?

And exactly how much "size" are we talking about here?  Did the
available memory size for new chips just increase more in me writing
this email than the size that this proposed patch would have offset?

greg k-h