[PATCH v4 9/9] ARM: dts: rockchip: support the spi for rk3036
Heiko Stuebner
heiko at sntech.de
Sun Jan 31 03:06:25 PST 2016
Hi Caesar,
Am Donnerstag, 28. Januar 2016, 16:43:38 schrieb Caesar Wang:
> You have to use the 4 bus to work if someone wants to support
> the spi devices, since the the pin is re-used by data[5-8] and spi.
> If support the spi making the happy work, that will waste the
> emmc performance.
>
> Moment, the kylin hasn't the spi devices to work, so maybe we need wait
> the new required to enable in kylin board.
>
> Anyway, the spi should be needed land in rk3036 dts.
>
> Signed-off-by: Caesar Wang <wxt at rock-chips.com>
>
> ---
>
> Changes in v4:
> - Add this patch included in kylin series patches.
>
> arch/arm/boot/dts/rk3036.dtsi | 42
> ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42
> insertions(+)
>
> diff --git a/arch/arm/boot/dts/rk3036.dtsi b/arch/arm/boot/dts/rk3036.dtsi
> index 532f232..40a5017 100644
> --- a/arch/arm/boot/dts/rk3036.dtsi
> +++ b/arch/arm/boot/dts/rk3036.dtsi
> @@ -60,6 +60,7 @@
> serial0 = &uart0;
> serial1 = &uart1;
> serial2 = &uart2;
> + spi = &spi;
> };
>
> memory {
> @@ -485,6 +486,23 @@
> status = "disabled";
> };
>
> + spi: spi at 20074000 {
> + compatible = "rockchip,rockchip-spi";
> + reg = <0x20074000 0x1000>;
> + interrupts = <GIC_SPI 23 IRQ_TYPE_LEVEL_HIGH>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + pinctrl-names = "default";
> + pinctrl-0 = <&spi_txd &spi_rxd &spi_clk &spi_cs0 &spi_cs1>;
Do we really want to enable both chip-selects by default?
On the rk3288 Lin Huang wrote:
* It's assumed that most users of the SPI ports are using chip select
0. Thus the default pinctrl for the ports enables chip select 0
(but not chip select 1 on ports that have it). If a board wants to
use chip select 1 or wants a GPIO chip select the board should
override the pinctrl (just like boards can override UART pinctrl if
they have hardware flow control).
Do we expect again mostly a use of cs0 or will in the major cases both chip-
selects be needed?
> + num-cs = <2>;
> + clocks =<&cru PCLK_SPI>, <&cru SCLK_SPI>;
> + clock-names = "apb-pclk","spi_pclk";
> + dmas = <&pdma 8>, <&pdma 9>;
> + #dma-cells = <2>;
What do you need #dma-cells for? This is not a dma-controller :-)
> + dma-names = "tx", "rx";
> + status = "disabled";
> + };
Also I'd suggest an ordering like:
+ spi: spi at 20074000 {
+ compatible = "rockchip,rockchip-spi";
+ reg = <0x20074000 0x1000>;
+ interrupts = <GIC_SPI 23 IRQ_TYPE_LEVEL_HIGH>;
+ clocks =<&cru PCLK_SPI>, <&cru SCLK_SPI>;
+ clock-names = "apb-pclk","spi_pclk";
+ dmas = <&pdma 8>, <&pdma 9>;
+ dma-names = "tx", "rx";
+ num-cs = <2>;
+ pinctrl-names = "default";
+ pinctrl-0 = <&spi_txd &spi_rxd &spi_clk &spi_cs0 &spi_cs1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ };
Heiko
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