On 25.08.2015 10:33, Yakir Yang wrote:
Hi Krzysztof,
在 2015/8/25 7:49, Krzysztof Kozlowski 写道:
On 24.08.2015 21:48, Yakir Yang wrote:
Hi Krzysztof,
在 08/24/2015 12:20 PM, Krzysztof Kozlowski 写道:
On 24.08.2015 11:42, Yakir Yang wrote:
Hi Krzysztof,
在 08/23/2015 07:43 PM, Krzysztof Kozlowski 写道:
2015-08-24 8:23 GMT+09:00 Rob Herring robherring2@gmail.com: > On Wed, Aug 19, 2015 at 9:50 AM, Yakir Yang ykk@rock-chips.com > wrote: >> Analogix dp driver is split from exynos dp driver, so we just >> make an copy of exynos_dp.txt, and then simplify exynos_dp.txt >> >> Beside update some exynos dtsi file with the latest change >> according to the devicetree binding documents. > You can't just change the exynos bindings and break > compatibility. Is > there some agreement with exynos folks to do this? No, there is no agreement. This wasn't even sent to Exynos maintainers.
Sorry about this one, actually I have add Exynos maintainers in version 1 & version 2, but lose some maintainers in version 3, I would fix it in bellow versions.
Additionally the patchset did not look interesting to me because of misleading subject - Documentation instead of "ARM: dts:".
Yakir, please:
- Provide backward compatibility. Mark old properties as deprecated
but still support them.
Do you mean that I should keep the old properties declare in exynos-dp.txt, but just mark them as deprecated flag.
That is one of ways how to do this. However more important is that driver should still support old bindings so such code:
if (of_property_read_u32(dp_node, "samsung,color-space",
if (of_property_read_u32(dp_node, "analogix,color-space",is probably wrong. Will the driver support old DTB in the same way as it was supporting before the change?
Okay, I got your means. So document is not the focus, the most important is that driver should support the old dts prop.
Right, the focus is on the driver.
If so the new analogix dp driver should keep the "samsung,color-space", rather then just mark it with [DEPRECATED] flag.
If you are replacing a binding/property then it should be marked deprecated. This means that the old property is still working but new users of it should not be added.
Okay, so just quote Heiko's reply, such code would be need in analogix dp driver.
if (of_property_read_u32(dp_node, "analogix,color-space", &dp_video_config->color_space)) if (of_property_read_u32(dp_node, "samsung,color-space", &dp_video_config->color_space)) { dev_err(dev, "failed to get color-space\n"); return ERR_PTR(-EINVAL); }
Yes. It does not look pretty but something like this is needed.
Best regards, Krzysztof