Problem with interfacing SPI device with wandboard dual

[aravinds]

Hi,
I'm using imx6 wandboard dual tried to configure spi1,

made device-tree changes:

-----------------------------------------------
...
&iomuxc {
...
    ecspi1 {
         pinctrl_ecspi1_cs: ecspi1cs {
                         fsl,pins = <
                             MX6QDL_PAD_EIM_EB2__ECSPI1_SS0  0x80000000
                             >;
                     };
 pinctrl_ecspi1: ecspi1grp {
                      fsl,pins = <
                          MX6QDL_PAD_EIM_D17__ECSPI1_MISO 0x100b1
                          MX6QDL_PAD_EIM_D18__ECSPI1_MOSI 0x100b1
                          MX6QDL_PAD_EIM_D16__ECSPI1_SCLK 0x100b1
                          >;
                  };
    };
...

...
&ecspi1 {
    fsl,spi-num-chipselects = <1>;
    pinctrl-names = "default";
    pinctrl-0 = <&pinctrl_ecspi1 &pinctrl_ecspi1_cs>;
    status = "okay";
    spidev@0x01 {
        compatible = "linux,lcd-st7565";
        spi-max-frequency = <20000000>;
        reg = <0x0>;
        register-sel-gpio =<&gpio4 5 0>;
        reset-gpio =<&gpio7 13 0>;
        backlight-gpio =<&gpio3 26 0>;
        status = "okay";
    };
};
...
----------------------------------------------------------------

but while connecting the LCD to the SPI, its not working (lcd-st7565 driver for my LCD, which is working fine as i get all debug prints)on probing the SPI pins with oscilloscope confirmed data is coming but in some distorted manner (overshoot undershoot problem),

kernel version 3.14.28

oscilloscope probed  : data line and clock
can anyone please guide me what is the reason for such a behavior..??

[igorpadykov]

Hi ARAVIND

lcd-st7565 driver should be integrated in linux framebuffer framework,

please follow  eLCDIF driver example described in Chapter 12 ELCDIF Frame Buffer Driver

attached Linux Manual. For debug testing one can use sect.6.4.1 Framebuffer Tests

Best regards
igor
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