Re: [RFC v3 08/13] ahci-platform: Allow specifying platform_data through of_device_id

Hi,

On 01/20/2014 10:09 AM, Sascha Hauer wrote:

On Mon, Jan 20, 2014 at 09:35:06AM +0100, Hans de Goede wrote:

quoted

Hi,

On 01/20/2014 09:24 AM, Sascha Hauer wrote:

quoted

quoted

+
+static const struct ahci_platform_data *ahci_get_pdata(struct device *dev)
+{
+	struct ahci_platform_data *pdata;
+	const struct of_device_id *of_id;
+
+	pdata = dev_get_platdata(dev);
+	if (pdata)
+		return pdata;
+
+	of_id = of_match_device(ahci_of_match, dev);
+	if (of_id)
+		return of_id->data;

I don't think it's a good idea to force of_id->data to be of type struct
struct ahci_platform_data *. With this we don't have a place to store
SoC specific data anymore.

?? ahci_platform_data *is* soc specific data, it allows various soc
specific overrides.

I know, but it might not be enough for encding the slight differences
between i.MX53 and i.MX6. So you say then we would need to different
instances of struct ahci_platform_data, one for i.MX53 and one for
i.MX6. Ok, that works.

Overall I must say that I'm not really happy with giving up control over
the probe function and putting ahci_platform as a midlayer between the
SoC and the ahci lib. Just my 2 cents, if I'm the only one feel free to
ignore me, but maybe there are others that have the same feeling.

I'm currently working on a slightly different implementation of a more
generic ahci_platform.c where ahci_platform.c exports some standard platform
related functionality as library functions.

Drivers which need to override some of ahci_platform.c's behavior because of
non standard hw, will then export their own struct platform_driver and can
call into the exported functions for standard stuff to avoid code duplication
where appropriate, while still having 100% freedom to do things in a custom
way where necessary.

I hope to post a PATCH RFC v4 with these changes later today, which you will
hopefully like better. Input on v4, even just a "yep better" remark would be
much appreciated.

Regards,

Hans

On Mon, Jan 20, 2014 at 10:17:24AM +0100, Hans de Goede wrote:

Hi,

I'm currently working on a slightly different implementation of a more
generic ahci_platform.c where ahci_platform.c exports some standard platform
related functionality as library functions.

Drivers which need to override some of ahci_platform.c's behavior because of
non standard hw, will then export their own struct platform_driver and can
call into the exported functions for standard stuff to avoid code duplication
where appropriate, while still having 100% freedom to do things in a custom
way where necessary.

Nice, thanks.

I hope to post a PATCH RFC v4 with these changes later today, which you will
hopefully like better. Input on v4, even just a "yep better" remark would be
much appreciated.

Yes, I will give feedback on v4.

Sascha

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