From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Christoph Hellwig <hch@lst.de>
Cc: Maxime Chevallier <maxime.chevallier@bootlin.com>,
Gavin Li <git@thegavinli.com>,
Laurentiu Tudor <laurentiu.tudor@nxp.com>,
Minas Harutyunyan <hminas@synopsys.com>,
Alan Stern <stern@rowland.harvard.edu>,
Geoff Levand <geoff@infradead.org>,
Michal Simek <michal.simek@xilinx.com>,
Shawn Guo <shawnguo@kernel.org>,
Sascha Hauer <s.hauer@pengutronix.de>,
Pengutronix Kernel Team <kernel@pengutronix.de>,
Fabio Estevam <festevam@gmail.com>,
NXP Linux Team <linux-imx@nxp.com>,
Olav Kongas <ok@artecdesign.ee>,
Tony Prisk <linux@prisktech.co.nz>,
Mathias Nyman <mathias.nyman@intel.com>, Bin Liu <b-liu@ti.com>,
linux-arm-kernel@lists.infradead.org, linux-usb@vger.kernel.org,
linuxppc-dev@lists.ozlabs.org, iommu@lists.linux-foundation.org,
linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 6/6] driver core: initialize a default DMA mask for platform device
Date: Thu, 15 Aug 2019 16:05:16 +0200 [thread overview]
Message-ID: <20190815140516.GB7174@kroah.com> (raw)
Message-ID: <20190815140516.eT2I-hqjRo5H3rmrHRGpkAJzKs59Dg5tfvYumzVlRvA@z> (raw)
In-Reply-To: <20190815133812.GF12036@lst.de>
On Thu, Aug 15, 2019 at 03:38:12PM +0200, Christoph Hellwig wrote:
> On Thu, Aug 15, 2019 at 03:03:25PM +0200, Greg Kroah-Hartman wrote:
> > > --- a/include/linux/platform_device.h
> > > +++ b/include/linux/platform_device.h
> > > @@ -24,6 +24,7 @@ struct platform_device {
> > > int id;
> > > bool id_auto;
> > > struct device dev;
> > > + u64 dma_mask;
> >
> > Why is the dma_mask in 'struct device' which is part of this structure,
> > not sufficient here? Shouldn't the "platform" be setting that up
> > correctly already in the "archdata" type callback?
>
> Becaus the dma_mask in struct device is a pointer that needs to point
> to something, and this is the best space we can allocate for 'something'.
> m68k and powerpc currently do something roughly equivalent at the moment,
> while everyone else just has horrible, horrible hacks. As mentioned in
> the changelog the intent of this patch is that we treat platform devices
> like any other bus, where the bus allocates the space for the dma_mask.
> The long term plan is to eventually kill that weird pointer indirection
> that doesn't help anyone, but for that we need to sort out the basics
> first.
Ah, missed that, sorry. Ok, no objection from me. Might as well respin
this series and I can queue it up after 5.3-rc5 is out (which will have
your first 2 patches in it.)
thanks,
greg k-h
next prev parent reply other threads:[~2019-08-15 14:05 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-11 8:05 next take at setting up a dma mask by default for platform devices Christoph Hellwig
2019-08-11 8:05 ` Christoph Hellwig
2019-08-11 8:05 ` [PATCH 1/6] usb: don't create dma pools for HCDs with a localmem_pool Christoph Hellwig
2019-08-11 8:05 ` Christoph Hellwig
2019-08-11 8:05 ` [PATCH 2/6] usb: add a hcd_uses_dma helper Christoph Hellwig
2019-08-11 8:05 ` Christoph Hellwig
2019-08-11 8:05 ` [PATCH 3/6] usb: add a HCD_DMA flag instead of guestimating DMA capabilities Christoph Hellwig
2019-08-11 8:05 ` Christoph Hellwig
[not found] ` <20190811080520.21712-4-hch-jcswGhMUV9g@public.gmane.org>
2019-08-12 11:57 ` Christoph Hellwig
2019-08-12 11:57 ` Christoph Hellwig
2019-08-11 8:05 ` [PATCH 4/6] usb/max3421: remove the dummy {un,}map_urb_for_dma methods Christoph Hellwig
2019-08-11 8:05 ` Christoph Hellwig
2019-08-11 8:05 ` [PATCH 5/6] dma-mapping: remove is_device_dma_capable Christoph Hellwig
2019-08-11 8:05 ` Christoph Hellwig
2019-08-11 8:05 ` [PATCH 6/6] driver core: initialize a default DMA mask for platform device Christoph Hellwig
2019-08-11 8:05 ` Christoph Hellwig
2019-08-14 15:49 ` Robin Murphy
2019-08-14 15:49 ` Robin Murphy
2019-08-15 13:32 ` Christoph Hellwig
2019-08-15 13:32 ` Christoph Hellwig
2019-08-15 13:03 ` Greg Kroah-Hartman
2019-08-15 13:03 ` Greg Kroah-Hartman
2019-08-15 13:38 ` Christoph Hellwig
2019-08-15 13:38 ` Christoph Hellwig
2019-08-15 14:05 ` Greg Kroah-Hartman [this message]
2019-08-15 14:05 ` Greg Kroah-Hartman
2019-08-15 13:23 ` next take at setting up a dma mask by default for platform devices Greg Kroah-Hartman
2019-08-15 13:23 ` Greg Kroah-Hartman
2019-08-15 13:25 ` Christoph Hellwig
2019-08-15 13:25 ` Christoph Hellwig
2019-08-15 14:05 ` Greg Kroah-Hartman
2019-08-15 14:05 ` Greg Kroah-Hartman
2019-08-15 14:39 ` Alan Stern
2019-08-15 14:39 ` Alan Stern
2019-08-16 6:24 next take at setting up a dma mask by default for platform devices v2 Christoph Hellwig
2019-08-16 6:24 ` [PATCH 6/6] driver core: initialize a default DMA mask for platform device Christoph Hellwig
2019-08-16 6:24 ` Christoph Hellwig
2019-08-16 7:39 ` Geert Uytterhoeven
2019-08-16 7:39 ` Geert Uytterhoeven
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190815140516.GB7174@kroah.com \
--to=gregkh@linuxfoundation.org \
--cc=b-liu@ti.com \
--cc=festevam@gmail.com \
--cc=geoff@infradead.org \
--cc=git@thegavinli.com \
--cc=hch@lst.de \
--cc=hminas@synopsys.com \
--cc=iommu@lists.linux-foundation.org \
--cc=kernel@pengutronix.de \
--cc=laurentiu.tudor@nxp.com \
--cc=linux-arch@vger.kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-imx@nxp.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=linux@prisktech.co.nz \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=mathias.nyman@intel.com \
--cc=maxime.chevallier@bootlin.com \
--cc=michal.simek@xilinx.com \
--cc=ok@artecdesign.ee \
--cc=s.hauer@pengutronix.de \
--cc=shawnguo@kernel.org \
--cc=stern@rowland.harvard.edu \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).