[PATCH v1 2/3] dt-bindings: display: Add STM32 DSI host driver

[Philippe CORNU]

On 05/18/2017 11:42 PM, Rob Herring wrote:
> On Fri, May 12, 2017 at 04:56:28PM +0200, Philippe CORNU wrote:
>> This patch adds documentation of device tree bindings for the STM32
>> DSI host driver based on the Synopsys DW MIPI DSI driver from Rockchip.
>>
>> Signed-off-by: Philippe CORNU <philippe.cornu at st.com>
>> ---
>>   .../devicetree/bindings/display/st,stm32-ltdc.txt  | 92 +++++++++++++++++++++-
>>   1 file changed, 90 insertions(+), 2 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/display/st,stm32-ltdc.txt b/Documentation/devicetree/bindings/display/st,stm32-ltdc.txt
>> index 8e14769..a61381b 100644
>> --- a/Documentation/devicetree/bindings/display/st,stm32-ltdc.txt
>> +++ b/Documentation/devicetree/bindings/display/st,stm32-ltdc.txt
>> @@ -1,7 +1,6 @@
>>   * STMicroelectronics STM32 lcd-tft display controller
>>   
>>   - ltdc: lcd-tft display controller host
>> -  must be a sub-node of st-display-subsystem
> 
> Why is this removed? The "must" refers to the location, not whether
> present or not if that's what you were trying to change.
> 
Dear Rob,
Many thanks for your comments.

There is no need anymore to have a st-display-subsystem parent node in 
the device tree for the ltdc, that is why I removed this "must" information.

>>     Required properties:
>>     - compatible: "st,stm32-ltdc"
>>     - reg: Physical base address of the IP registers and length of memory mapped region.
>> @@ -13,8 +12,25 @@
>>     Required nodes:
>>       - Video port for RGB output.
>>   
>> -Example:
>> +* STMicroelectronics STM32 specific extensions to Synopsys Designware MIPI DSI
>> +(similar to "rockchip/dw_mipi_dsi_rockchip.txt")
>>   
>> +Required properties:
>> +- #address-cells: Should be <1>.
>> +- #size-cells: Should be <0>.
>> +- compatible: "st,stm32-dsi_host".
> 
> Don't use '_' and this needs to be more specific than just "stm32".
> 
Fixed in v2 patchset.

>> +- reg: Represent the physical address range of the controller.
>> +- clocks, clock-names: Phandles to the controller's pll reference
>> +  clock(ref) and APB clock(pclk). As described in [1].
> 
> Ideally these should be in a common binding (like the driver) as a given
> IP block doesn't have a varying number of clocks (typically).
> 
Updated in v2 patchset.

>> +- ports: contain a port node with endpoint definitions as defined in [2].
> 
> a single port? Need to be clear how many ports/endpoints and their
> function.
> 
Updated in v2 patchset.

>> +- resets: list of phandle + reset specifier pairs, as described in [3].
>> +- reset-names: string reset name, must be "apb".
>> +
>> +[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
>> +[2] Documentation/devicetree/bindings/media/video-interfaces.txt
>> +[3] Documentation/devicetree/bindings/reset/reset.txt
>> +
>> +Example 1: RGB panel
>>   / {
>>   	...
>>   	soc {
>> @@ -34,3 +50,75 @@ Example:
>>   		};
>>   	};
>>   };
>> +
>> +Example 2: DSI panel
>> +
>> +/ {
>> +	...
>> +	soc {
>> +	...
>> +		ltdc: display-controller at 40016800 {
>> +			compatible = "st,stm32-ltdc";
>> +			reg = <0x40016800 0x200>;
>> +			interrupts = <88>, <89>;
>> +			resets = <&rcc STM32F4_APB2_RESET(LTDC)>;
>> +			clocks = <&rcc 1 CLK_LCD>;
>> +			clock-names = "lcd";
>> +
>> +			port {
>> +				ltdc_out_dsi_host: endpoint {
>> +					remote-endpoint = <&dsi_host_in>;
>> +				};
>> +			};
>> +		};
>> +
>> +
>> +		dsi_host: dsi_host at 40016C00 {
> 
> dsi at ...
> 
Fixed in v2 patchset.

>> +			#address-cells = <1>;
>> +			#size-cells = <0>;
>> +			compatible = "st,stm32-dsi_host";
>> +			reg = <0x40016C00 0x800>;
>> +			clocks = <&rcc 1 CLK_F469_DSI>, <&clk_hse>;
>> +			clock-names = "ref", "pclk";
>> +			resets = <&rcc STM32F4_APB2_RESET(DSI)>;
>> +			reset-names = "apb";
>> +			status = "okay";
> 
> Don't show status in examples.
Fixed in v2 patchset.

>> +
>> +			ports {
>> +				#address-cells = <1>;
>> +				#size-cells = <0>;
>> +
>> +				port at 0 {
>> +					reg = <0>;
>> +					dsi_host_in: endpoint {
>> +						remote-endpoint = <&ltdc_out_dsi_host>;
>> +					};
>> +				};
>> +
>> +				port at 1 {
>> +					reg = <1>;
>> +					dsi_host_out_panel: endpoint {
>> +						remote-endpoint = <&dsi_host_in_panel>;
>> +					};
>> +				};
>> +
>> +			};
>> +
>> +			panel-dsi at 0 {
>> +				reg = <0>; /* dsi virtual channel (0..3) */
>> +				compatible = ...;
>> +				enable-gpios = ...;
>> +				status = "okay";
>> +
>> +				port {
>> +					dsi_host_in_panel: endpoint {
>> +						remote-endpoint = <&dsi_host_out_panel>;
>> +					};
>> +				};
>> +
>> +			};
>> +
>> +		};
>> +
>> +	};
>> +};
>> -- 
>> 1.9.1
>>
>>
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