Re: [PATCH 1/5] serial: 8250_pci: use DEFINE_PCI_DEVICE_TABLE macro

[Joe Perches <joe@perches.com>]

(Adding Jonas Bonn to list as he added the macro in the first place...)

On Mon, 2013-12-02 at 13:03 +0900, Jingoo Han wrote:
> On Monday, December 02, 2013 12:56 PM, Guenter Roeck wrote:
> > On 12/01/2013 07:50 PM, Jingoo Han wrote:
> > > On Monday, December 02, 2013 12:46 PM, Guenter Roeck wrote:
> > >> On 12/01/2013 04:07 PM, Jingoo Han wrote:
> > >>> On Friday, November 29, 2013 10:34 AM, Jingoo Han wrote:
> > >>>> On Thursday, November 28, 2013 3:24 PM, Joe Perches wrote:
> > >>>>> On Wed, 2013-11-27 at 21:53 -0800, 'Greg Kroah-Hartman' wrote:
> > >>>>>> On Wed, Nov 27, 2013 at 09:40:13PM -0800, Joe Perches wrote:
> > >>>>>>> On Thu, 2013-11-28 at 14:29 +0900, Jingoo Han wrote:
> > >>>>>>>> On Thursday, November 28, 2013 1:08 PM, Greg Kroah-Hartman wrote:
> > >>>>>>>>> On Thu, Nov 28, 2013 at 10:55:35AM +0900, Jingoo Han wrote:
> > >>>>>>>>>> This macro is used to create a struct pci_device_id array.
> > >>>>>>>>>
> > >>>>>>>>> Yeah, and it's a horrid macro that deserves to be removed, please don't
> > >>>>>>>>> use it in more places.
> > >>>>>>>>>
> > >>>>>>>>> Actually, if you could just remove it, that would be best, sorry, I'm
> > >>>>>>>>> not going to take these patches.
> > >>>>>>>>
> > >>>>>>>> (+cc Joe Perches, Andrew Morton, Andy Whitcroft)
> > >>>>>>>>
> > >>>>>>>> Hi Joe Perches,
> > >>>>>>>>
> > >>>>>>>> Would you fix checkpatch.pl about DEFINE_PCI_DEVICE_TABLE?
> > >>>>>>>> Currently, checkpatch.pl guides to use DEFINE_PCI_DEVICE_TABLE
> > >>>>>>>> as below.
> > >>>>>>>>
> > >>>>>>>>     WARNING: Use DEFINE_PCI_DEVICE_TABLE for struct pci_device_id
> > >>>>>>>>     #331: FILE: drivers/usb/host/ehci-pci.c:331:
> > >>>>>>>>     +static const struct pci_device_id pci_ids [] = { {
> > >>>>>>>>
> > >>>>>>>> However, Greg Kroah-Hartman mentioned that DEFINE_PCI_DEVICE_TABLE
> > >>>>>>>> shouldn't be used anymore.
> > >>>>>>>>
> > >>>>>>>> So, would you change checkpatch.pl in order to guide to use
> > >>>>>>>> struct pci_device_id instead of DEFINE_PCI_DEVICE_TABLE?
> > >>>>>>>>
> > >>>>>>>> For example,
> > >>>>>>>>     WARNING: Use struct pci_device_id instead of DEFINE_PCI_DEVICE_TABLE
> > >>>>>>>
> > >>>>>>> The documentation doesn't agree with Greg.
> > >>>>> []
> > >>>>>> I say just remove it, I should have done that years ago when I was the
> > >>>>>> PCI maintainer, just never got around to it.  No other bus has something
> > >>>>>> like this for their device ids, why should PCI be "special"?
> > >>>>>
> > >>>>> Anyone else have an opinion?
> > >>>>>
> > >>>>> I don't care one way or another, but please, one way
> > >>>>> not two.
> > >>>>
> > >>
> > >> Same here.
> > >>
> > >>>> (+cc Bjorn Helgaas, linux-pci)
> > >>>>
> > >>>> Then, how about the following steps?
> > >>>>
> > >>>> 1. Fix ./Documentation/PCI/pci.txt as below.
> > >>>>      (Jingoo Han)
> > >>>>      The ID table is an array of struct pci_device_id entries ending with an
> > >>>>      -all-zero entry; use of the macro DEFINE_PCI_DEVICE_TABLE is the preferred
> > >>>>      -method of declaring the table.  Each entry consists of:
> > >>>>      +all-zero entry; Each entry consists of:
> > >>>>
> > >>>> 2. Fix ./scripts/checkpatch.pl in order to guide to use
> > >>>>       struct pci_device_id instead of DEFINE_PCI_DEVICE_TABLE.
> > >>>>       (Joe Perches)
> > >>>
> > >>> If all DEFINE_PCI_DEVICE_TABLEs are replaced with 'const struct pci_device_id'
> > >>> and these patches are merged through 'driver-core.git', it will be not
> > >>> necessary to fix ./scripts/checkpatch.pl.
> > >>>
> > >> Why not ?
> > >
> > > I will replace all DEFINE_PCI_DEVICE_TABLEs with 'const struct pci_device_id',
> > > and remove the definition of DEFINE_PCI_DEVICE_TABLE macro.
> > >
> > > --- a/include/linux/pci.h
> > > +++ b/include/linux/pci.h
> > > @@ -631,16 +631,6 @@ struct pci_driver {
> > >   #define        to_pci_driver(drv) container_of(drv, struct pci_driver, driver)
> > >
> > >   /**
> > > - * DEFINE_PCI_DEVICE_TABLE - macro used to describe a pci device table
> > > - * @_table: device table name
> > > - *
> > > - * This macro is used to create a struct pci_device_id array (a device table)
> > > - * in a generic manner.
> > > - */
> > > -#define DEFINE_PCI_DEVICE_TABLE(_table) \
> > > -       const struct pci_device_id _table[]
> > > -
> > > -/**
> > >
> > > In this case, there is no DEFINE_PCI_DEVICE_TABLE usage
> > > in the kernel. If someone uses DEFINE_PCI_DEVICE_TABLE macro,
> > > it will make  build error.
> > >
> > 
> > And that will make the checkpatch warning go away ?
> > That seems to be very unlikely.
> 
> OK, I will ask Joe Perches to remove the following checkpatch
> warning.
> 
>     WARNING: Use DEFINE_PCI_DEVICE_TABLE for struct pci_device_id
> 
> Best regards,
> Jingoo Han
>