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 15:03:25 +0200 [thread overview]
Message-ID: <20190815130325.GB17065@kroah.com> (raw)
Message-ID: <20190815130325.vTAQ299oE6WhHrwNwJGfVfD6up-Y0OWP63BklnhKOgc@z> (raw)
In-Reply-To: <20190811080520.21712-7-hch@lst.de>
On Sun, Aug 11, 2019 at 10:05:20AM +0200, Christoph Hellwig wrote:
> We still treat devices without a DMA mask as defaulting to 32-bits for
> both mask, but a few releases ago we've started warning about such
> cases, as they require special cases to work around this sloppyness.
> Add a dma_mask field to struct platform_object so that we can initialize
> the dma_mask pointer in struct device and initialize both masks to
> 32-bits by default. Architectures can still override this in
> arch_setup_pdev_archdata if needed.
>
> Note that the code looks a little odd with the various conditionals
> because we have to support platform_device structures that are
> statically allocated.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
> drivers/base/platform.c | 15 +++++++++++++--
> include/linux/platform_device.h | 1 +
> 2 files changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/base/platform.c b/drivers/base/platform.c
> index ec974ba9c0c4..b216fcb0a8af 100644
> --- a/drivers/base/platform.c
> +++ b/drivers/base/platform.c
> @@ -264,6 +264,17 @@ struct platform_object {
> char name[];
> };
>
> +static void setup_pdev_archdata(struct platform_device *pdev)
> +{
> + if (!pdev->dev.coherent_dma_mask)
> + pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
> + if (!pdev->dma_mask)
> + pdev->dma_mask = DMA_BIT_MASK(32);
> + if (!pdev->dev.dma_mask)
> + pdev->dev.dma_mask = &pdev->dma_mask;
> + arch_setup_pdev_archdata(pdev);
> +};
> +
> /**
> * platform_device_put - destroy a platform device
> * @pdev: platform device to free
> @@ -310,7 +321,7 @@ struct platform_device *platform_device_alloc(const char *name, int id)
> pa->pdev.id = id;
> device_initialize(&pa->pdev.dev);
> pa->pdev.dev.release = platform_device_release;
> - arch_setup_pdev_archdata(&pa->pdev);
> + setup_pdev_archdata(&pa->pdev);
> }
>
> return pa ? &pa->pdev : NULL;
> @@ -512,7 +523,7 @@ EXPORT_SYMBOL_GPL(platform_device_del);
> int platform_device_register(struct platform_device *pdev)
> {
> device_initialize(&pdev->dev);
> - arch_setup_pdev_archdata(pdev);
> + setup_pdev_archdata(pdev);
> return platform_device_add(pdev);
> }
> EXPORT_SYMBOL_GPL(platform_device_register);
> diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h
> index 9bc36b589827..a2abde2aef25 100644
> --- 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?
confused,
greg k-h
next prev parent reply other threads:[~2019-08-15 13:03 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 [this message]
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
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=20190815130325.GB17065@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).