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标题: AM4379拓展接口SPI2片选问题 [打印本页]

作者: jyorin 时间: 2018-12-11 09:50
标题: AM4379拓展接口SPI2片选问题
原理图
[attach]4524[/attach]

设备树文件
spi@481a2000 {
                     compatible = "ti,am4372-mcspi", "ti,omap4-mcspi";
                     reg = <0x481a2000 0x400>;
                     interrupts = <0x0 0x7e 0x4>;
                     ti,spi-num-cs = <0x2>;
                     ti,pindir-d0-out-d1-in = <0x1>;
                     ti,hwmods = "spi2";
                     dmas = <0x28 0x10 0x28 0x11 0x28 0x12 0x28 0x13>;
                     dma-names = "tx0", "rx0", "tx1", "rx1";
                     #address-cells = <0x1>;
                     #size-cells = <0x0>;
                     status = "okay";
                     pinctrl-names = "default";
                     pinctrl-0 = <0x3e>;

                     ads7846@0 {
                              pinctrl-names = "default";
                              pinctrl-0 = <0x3f>;
                              compatible = "ti,ads7846";
                              vcc-supply = <0x40>;
                              reg = <0x0>;
                              spi-max-frequency = <0x16e360>;
                              interrupt-parent = <0x41>;
                              interrupts = <0x7 0x0>;
                              pendown-gpio = <0x41 0x7 0x0>;
                              ti,x-min = [00 00];
                              ti,x-max = [0f ff];
                              ti,y-min = [00 00];
                              ti,y-max = [0f ff];
                              ti,x-plate-ohms = [00 b4];
                              ti,pressure-max = [00 ff];
                              ti,debounce-max = [00 0a];
                              ti,debounce-tol = [00 1e];
                              ti,debounce-rep = [00 01];
                              ti,settle-delay-usec = [00 96];
                              ti,keep-vref-on = <0x1>;
                              linux,wakeup;
                     };

                     spi@1 {
                              spi-max-frequency = <0x16e3600>;
                              reg = <0x1>;
                              compatible = "spidev";
                     };
            };

结果：
spi2按原理图上的管脚，片选CS没有输出

作者: jyorin 时间: 2018-12-11 11:35
[attach]4525[/attach]
怎么样才能片选信号输出

作者: 544864579 时间: 2018-12-11 14:10
确认spi的pinmux是否配置正常了。

作者: czs----Tronlong 时间: 2018-12-11 15:01
您好，

关于拓展接口的SPI2引脚，我司默认情况下是没有配置的，您需要参照我们提供的设备树文件，确认您需要使用的SPI2引脚以及片选信号都已正确配置。

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