On Thu, Aug 12, 2010 at 12:25 AM, Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx> wrote: > On Thu, Aug 12, 2010 at 12:57:18AM +0530, DebBarma, Tarun Kanti wrote: >> >> > -----Original Message----- >> > From: Felipe Balbi [mailto:felipe.balbi@xxxxxxxxx] >> > Sent: Thursday, August 12, 2010 12:27 AM >> > To: DebBarma, Tarun Kanti >> > Cc: Balbi Felipe (Nokia-MS/Helsinki); Ohad Ben-Cohen; linux- >> > wireless@xxxxxxxxxxxxxxx; linux-mmc@xxxxxxxxxxxxxxx; linux- >> > omap@xxxxxxxxxxxxxxx; Ido Yariv; Mark Brown; linux-arm- >> > kernel@xxxxxxxxxxxxxxxxxxx; Chikkature Rajashekar, Madhusudhan; Coelho >> > Luciano (Nokia-MS/Helsinki); akpm@xxxxxxxxxxxxxxxxxxxx; San Mehat; Quadros >> > Roger (Nokia-MS/Helsinki); Tony Lindgren; Nicolas Pitre; Pandita, Vikram; >> > Kalle Valo >> > Subject: Re: [PATCH v4 3/8] wireless: wl1271: add platform driver to get >> > board data >> > >> > Hi, >> > >> > On Wed, Aug 11, 2010 at 08:52:54PM +0200, ext DebBarma, Tarun Kanti wrote: >> > >True; however if we go by that argument than we can also assume pdata >> > >is valid, so that we would not need the below check. >> > >> > of course not. You can have devices that just play well with default >> > values or devices where you don't need the flexibility of platform data. >> > That's why we check. >> > >> > platform_device pointers on the other hand, are guaranteed to be always >> > true, if it isn't then you should oops, you deserve to oops because >> > something is really really wrong. >> > >> Sounds perfect! >> What that means is _probe() function makes sense only for cases where we >> have valid platform data because we are returning right at the top if >> pdata is not valid. If this is the case I was curious to know why not >> framework make another check for valid pdata before calling _probe() >> instead of coming all the way to _probe() and then returning! > > Platform devices are not for passing platform data around - they're for > declaring platform hardware devices that we want drivers to handle - > and it depends on the driver whether having platform data is appropriate > or not. > > This proposal is, IMHO, abusing the platform device/driver support to > achieve its own goals. I've outlined a far simpler and easiler solution > which avoids this kind of abuse, and given suggestions on how to extend > it to support multiple instances. Thanks, Russell. I'll give your suggestion a spin when I get back (I'm going to be away for some time now with no devices with me). -- 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
