On 2016年07月25日 23:21, Thierry Reding wrote:
On Wed, Jul 20, 2016 at 11:18:50AM +0800, Mark Yao wrote:

Allow user add display timing on device tree with simple-panel-dsi
or simple-panel.

Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>

Signed-off-by: Mark Yao <mark.yao@rock-chips.com>
---
 .../bindings/display/panel/simple-panel.txt        | 48 ++++++++++++++++++++++
 1 file changed, 48 insertions(+)

Sorry, not going to happen. Read this for an explanation of why not:

	https://sietch-tagr.blogspot.de/2016/04/display-panels-are-not-special.html

Thierry

Hi Thierry

The blog actually not persuade me why can't use display timing on device tree.

1, Binding panel as a simple string on device tree seems simple on device tree, but it's complex on kernel code, and kernel code would became bigger and bigger.

2, Our customer always ask me, where is the display timing? They only find a simple panel string on device tree,  need search the kernel code to find the actually timing. They are used to find all device info on device tree, but panel timing info is not, this would confuse them. They don't want to know how code work, just want a easier interface.

3, I think device tree not only can use for kernel, other module also can use it. on our project, we use uboot + kernel, the uboot support fdt, that function can parsing device tree. So if describe the display timing on device tree, both uboot and kernel can share same display timing, not need to describe twice, it would save work and not easy to make mistake.

4, For differentiation product, we face many different panel, every once in a while, need to add a new panel, we can't convert all the panel , code the panel on kernel seems too bad, and the kernel image became bigger and bigger.
 
Generally, Our customer don't want to do any modify on kernel, they just modify device tree to bring up their device. Describe the panel timing on device tree, would make customer easy to use and reuse it.

Thanks.
-- 
Ｍark Yao