Re: [PATCH v3 0/5] bq27xxx_battery data memory update

[Julia Lawall <julia.lawall@lip6.fr>]

On Tue, 29 Aug 2017, Liam Breck wrote:

> Coccinelle folks,
>
> On Tue, Aug 29, 2017 at 5:29 PM, Sebastian Reichel
> <sebastian.reichel@collabora.co.uk> wrote:
> > Hi,
> >
> > On Tue, Aug 29, 2017 at 04:07:12PM -0700, Liam Breck wrote:
> >> I don't see a Julia in CC list...
> >
> > <_< let's try that again.
> >
> >> On Tue, Aug 29, 2017 at 2:22 PM, Sebastian Reichel
> >> <sebastian.reichel@collabora.co.uk> wrote:
> >> > [adding Julia to Cc for Coccinelle question]
> >> >
> >> > Hi,
> >> >
> >> > On Tue, Aug 29, 2017 at 10:31:57AM -0500, Andrew F. Davis wrote:
> >> >> On 08/29/2017 05:54 AM, Sebastian Reichel wrote:
> >> >> > On Wed, Aug 23, 2017 at 08:36:12PM -0700, Liam Breck wrote:
> >> >> >> Overview:
> >> >> >> * Reorganizes chip data definitions
> >> >> >> * Enables features landed in these patches:
> >> >> >>   dt-bindings: power: supply: bq27xxx: Add monitored-battery documentation
> >> >> >>   power: supply: bq27xxx: Add chip data memory read/write support
> >> >> >>   power: supply: bq27xxx: Add power_supply_battery_info support
> >> >> >> * Supports the following chips (only BQ27425 is active)
> >> >> >>   BQ27500, 545, 425, 421, 441, 621
> >> >> >>
> >> >> >> Changes in v3:
> >> >> >> * BQ27425 tested; workaround minor chip bug
> >> >> >> * Dropped driver_version
> >> >> >> * Fixed dbg_dupes logic for .props & .dm_regs
> >> >> >> * Dropped two props array dupes
> >> >> >>
> >> >> >> Changes in v2:
> >> >> >> * Added di->opts flags for remaining chip features
> >> >> >> * Commented out untested bq27xxx_dm_regs parameters
> >> >> >> * Changed dbg_dupes to run only once
> >> >> >>
> >> >> >> Notes on v1:
> >> >> >> * Not fully tested (hence RFC tag)
> >> >> >
> >> >> > Thanks, full series queued.
> >> >> >
> >> >> > -- Sebastian
> >> >>
> >> >> Anyway, I've not got the time to fight these changes anymore, but at
> >> >> very least could you drop 4/5, it's static analysis code made into a
> >> >> runtime check built into a kernel driver, if not at least add my
> >> >> nacked-by. :)
> >> >
> >> > Since it's not critical at all and nobody depends on it, I dropped 4/5
> >> > for now. I agree, that checking it at runtime is not nice. On the other
> >> > hand I do think a duplication check makes sense. Doing a static
> >> > check should be possible, but I have no idea how to implement this
> >> > (without much effort). I suspect Coccinelle can do it, so I added
> >> > Julia.
> >> >
> >> > For reference this is the runtime check:
> >> > https://patchwork.kernel.org/patch/9918953/
>
> The data structures being checked start here:
> https://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply.git/tree/drivers/power/supply/bq27xxx_battery.c?h=for-next#n138
>
> And are aggregated here:
> https://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply.git/tree/drivers/power/supply/bq27xxx_battery.c?h=for-next#n743

I worked a bit on this, but unfortunately there is a major parsing
problem, and most of the definitions are ignored.  Specifically, the
definitions of the regs variables are interspersed with eg:

#define bq27510g1_regs bq27500_regs

I'm not sure whether this would be convenient to fix, since parsing is
rather delicate.  Coccinelle doesn't run cpp first.  It tries to parse
macros definitions so that their code can be transformed as needed t the
place of the definition.

julia