> -----Original Message----- > From: Kevin Hilman [mailto:khilman@xxxxxx] > Sent: Thursday, February 10, 2011 10:07 PM > To: Vishwanath Sripathy > Cc: linux-omap@xxxxxxxxxxxxxxx; patches@xxxxxxxxxx; Thara Gopinath > Subject: Re: [PATCH 04/13] OMAP: Introduce dependent voltage domain > support > > Vishwanath Sripathy <vishwanath.bs@xxxxxx> writes: > > [...] > > >> > diff --git a/arch/arm/mach-omap2/dvfs.c b/arch/arm/mach- > >> omap2/dvfs.c > >> > index cefc2be..c9d3894 100755 > >> > --- a/arch/arm/mach-omap2/dvfs.c > >> > +++ b/arch/arm/mach-omap2/dvfs.c > >> > @@ -85,6 +85,7 @@ struct omap_vdd_dvfs_info { > >> > struct mutex scaling_mutex; /* dvfs mutex */ > >> > struct voltagedomain *voltdm; > >> > struct list_head dev_list; > >> > + struct device vdd_device; > >> > >> It's not clear what the usage of this device is for. > >> > >> It is never initialized, but seems to be used as a dummy device when > >> calcluating dependencies. Needs clarification. > > > > This device is used for placing voltage request > (omap_dvfs_add_vdd_user) > > when dealing with dependent vdds. Eg: while scaling MPU VDD, we > also scale > > CORE VDD. So while placing voltage request for CORE VDD, this > vdd_device > > of MPU is used as the requesting device so that this request is stored > as > > a separate user. > > I was able to follow how it was used, and why. But it is still not > clear to the reader. > > First, the device is never initialized, so it's essentially a dummy > device that remains initialized by default to all zeros. So, any > attempt to use any device APIs (e.g. dev_name, etc.) on this will not > behave as expected. > > Second, the reason for this device and the need for the request to be > stored as a separate user are not clear in the code and don't exist in > the comments. OK. I will add more comments to make these details more explicit. Vishwa > > Kevin > > > > -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
