[原创] BeagleBone Black设计: linux-rt-4.4.19下修改am335x-boneblack.dts实现外围驱动

anananjjj 2018-5-3 23:12 楼主

硬件平台是基于BeagleBone Black设计的扩展板： https://bbs.eeworld.com.cn/thread-440975-1-1.html在这之前所有的外围驱动都是直接编辑板级文件，将代码直接编译进内核的！更新到内核linux-rt-4.4.19后，可直接利用设备树进行设备的开发，关于设备树的介绍，大家可自行检索，我不再赘述。

具体步骤：

使能rt系统的LCD。

先找到要修改的文件:

/opt/ti-processor-sdk-linux-rt-am335x-evm-03.01.00.06/board-support/linux-rt-4.4.19+gitAUTOINC+f572d285f0-gf572d285f0/arch/arm/boot/dts/am335x-boneblack.dts

看一看其内容：

发现，其显示部分使能的时HDMI，所以参考am335x-evm.dts，现将LCD功能加进去！

去掉HDMI和其sound（i2c0）的功能，使用板载的LCD和声卡！

首先加LCD显示和背光控制功能，保留bbb板的ldo,rtc等功能，

执行：

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- distclean

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- tisdk_am335x-evm-rt_defconfig

（tisdk_am335x-evm-rt_defconfig存在于目录：/opt/ti-processor-sdk-linux-rt-am335x-evm-03.01.00.06/board-support/linux-rt-4.4.19+gitAUTOINC+f572d285f0-gf572d285f0/arch/arm/configs）

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- menuconfig

（屡次报错：In file included from scripts/kconfig/mconf.c:23:0:

scripts/kconfig/lxdialog/dialog.h:38:20: fatal error: curses.h: 没有那个文件或目录

#include CURSES_LOC

compilation terminated.

make[1]: *** [scripts/kconfig/mconf.o] 错误 1

make: *** [menuconfig] 错误 2

原因：提示了scripts/kconfig/lxdialog/dialog.h:38:20，一看就是没有相关依赖库，于是百度了一下，大家都说是缺少libcurses5-dev这个东西

解决方案：

）sudo apt-get install libncurses5-dev

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- zImage

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- am335x-boneblack.dtb

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- modules

sudo cp arch/arm/boot/zImage /media/anananjjj/rootfs/boot

sudo cp arch/arm/boot/dts/am335x-boneblack.dtb /media/anananjjj/rootfs/boot

sudo make ARCH=arm INSTALL_MOD_PATH=/media/anananjjj/rootfs modules_install

执行完毕后，LCD功能测试成功！！

具体调试：

修改：

panel {

compatible = "ti,tilcdc,panel";

status = "okay";

pinctrl-names = "default";

pinctrl-0 = <&lcd_pins_s0>;

panel-info {

ac-bias = <255>;

ac-bias-intrpt = <0>;

dma-burst-sz = <16>;

bpp = <32>;

fdd = <0x80>;

sync-edge = <0>;

sync-ctrl = <1>;

raster-order = <0>;

fifo-th = <0>;

};

display-timings {

800x480p62 {

clock-frequency = <30000000>;

hactive = <800>;

vactive = <480>;

hfront-porch = <39>;

hback-porch = <39>;

hsync-len = <47>;

vback-porch = <29>;

vfront-porch = <13>;

vsync-len = <2>;

hsync-active = <1>;

vsync-active = <1>;

};

增加引脚设置：

lcd_pins_s0: lcd_pins_s0 {

pinctrl-single,pins = <

0x20 (PIN_OUTPUT | MUX_MODE1) /* gpmc_ad8.lcd_data23 */

0x24 (PIN_OUTPUT | MUX_MODE1) /* gpmc_ad9.lcd_data22 */

0x28 (PIN_OUTPUT | MUX_MODE1) /* gpmc_ad10.lcd_data21 */

0x2c (PIN_OUTPUT | MUX_MODE1) /* gpmc_ad11.lcd_data20 */

0x30 (PIN_OUTPUT | MUX_MODE1) /* gpmc_ad12.lcd_data19 */

0x34 (PIN_OUTPUT | MUX_MODE1) /* gpmc_ad13.lcd_data18 */

0x38 (PIN_OUTPUT | MUX_MODE1) /* gpmc_ad14.lcd_data17 */

0x3c (PIN_OUTPUT | MUX_MODE1) /* gpmc_ad15.lcd_data16 */

0xa0 (PIN_OUTPUT | MUX_MODE0) /* lcd_data0.lcd_data0 */

0xa4 (PIN_OUTPUT | MUX_MODE0) /* lcd_data1.lcd_data1 */

0xa8 (PIN_OUTPUT | MUX_MODE0) /* lcd_data2.lcd_data2 */

0xac (PIN_OUTPUT | MUX_MODE0) /* lcd_data3.lcd_data3 */

0xb0 (PIN_OUTPUT | MUX_MODE0) /* lcd_data4.lcd_data4 */

0xb4 (PIN_OUTPUT | MUX_MODE0) /* lcd_data5.lcd_data5 */

0xb8 (PIN_OUTPUT | MUX_MODE0) /* lcd_data6.lcd_data6 */

0xbc (PIN_OUTPUT | MUX_MODE0) /* lcd_data7.lcd_data7 */

0xc0 (PIN_OUTPUT | MUX_MODE0) /* lcd_data8.lcd_data8 */

0xc4 (PIN_OUTPUT | MUX_MODE0) /* lcd_data9.lcd_data9 */

0xc8 (PIN_OUTPUT | MUX_MODE0) /* lcd_data10.lcd_data10 */

0xcc (PIN_OUTPUT | MUX_MODE0) /* lcd_data11.lcd_data11 */

0xd0 (PIN_OUTPUT | MUX_MODE0) /* lcd_data12.lcd_data12 */

0xd4 (PIN_OUTPUT | MUX_MODE0) /* lcd_data13.lcd_data13 */

0xd8 (PIN_OUTPUT | MUX_MODE0) /* lcd_data14.lcd_data14 */

0xdc (PIN_OUTPUT | MUX_MODE0) /* lcd_data15.lcd_data15 */

0xe0 (PIN_OUTPUT | MUX_MODE0) /* lcd_vsync.lcd_vsync */

0xe4 (PIN_OUTPUT | MUX_MODE0) /* lcd_hsync.lcd_hsync */

0xe8 (PIN_OUTPUT | MUX_MODE0) /* lcd_pclk.lcd_pclk */

0xec (PIN_OUTPUT | MUX_MODE0) /* lcd_ac_bias_en.lcd_ac_bias_en */

};

增加：

&lcdc {

status = "okay";

};

添加触摸驱动edt_ft5x06！

接下来修改设备树文件！

增加i2C2

//cap touch pins set

i2c2_pins: pinmux_i2c2_pins {

pinctrl-single,pins = <

0x178 (PIN_INPUT_PULLUP | MUX_MODE3) /* uart1_ctsn.i2c2_sda */

0x17c (PIN_INPUT_PULLUP | MUX_MODE3) /* uart1_rtsn.i2c2_scl */

};

edt_ft5x06_ts_pins: edt_ft5x06_ts_pins {

pinctrl-single,pins = <

0x1a0 (PIN_INPUT | MUX_MODE7) /* mcasp0_aclkr.gpio3_18 */

};

&i2c2 {

pinctrl-names = "default";

pinctrl-0 = <&i2c2_pins>;

status = "okay";

clock-frequency = <100000>;

//i2c device address:0x38

polytouch: edt-ft5x06@38 {

status = "okay";

compatible = "edt,edt-ft5x06";

pinctrl-names = "default";

pinctrl-0 = <&edt_ft5x06_ts_pins>;

reg = <0x38>;

interrupt-parent = <&gpio3>;

interrupts = <18 IRQ_TYPE_EDGE_FALLING>;

// reset-gpios = <&gpio3 18 GPIO_ACTIVE_LOW>;

// wake-gpios = <&gpio3 18 GPIO_ACTIVE_LOW>;

touchscreen-size-x = <800>;

touchscreen-size-y = <480>;

//touchscreen-inverted-x;

//touchscreen-swapped-x-y;

};

增加codec tlv320aic3106 驱动！

sound {

compatible = "simple-audio-card";

simple-audio-card,name = "AM335x-EVM";

simple-audio-card,widgets =

"Headphone", "Headphone Jack",

"Line", "Line In";

simple-audio-card,routing =

"Headphone Jack", "HPLOUT",

"Headphone Jack", "HPROUT",

"LINE1L", "Line In",

"LINE1R", "Line In";

simple-audio-card,format = "dsp_b";

simple-audio-card,bitclock-master = <&sound_master>;

simple-audio-card,frame-master = <&sound_master>;

simple-audio-card,bitclock-inversion;

simple-audio-card,cpu {

sound-dai = <&mcasp0>;

};

sound_master: simple-audio-card,codec {

sound-dai = <&tlv320aic3106>;

system-clock-frequency = <12000000>;

};

mcasp0_pins: mcasp0_pins {

pinctrl-single,pins = <

0x190 (PIN_INPUT_PULLDOWN | MUX_MODE0) /* mcasp0_aclkx.mcasp0_aclkx, INPUT | MODE0 */

0x194 (PIN_INPUT_PULLDOWN | MUX_MODE0) /* mcasp0_fsx.mcasp0_fsx, INPUT | MODE0 */

0x19c (PIN_OUTPUT_PULLDOWN | MUX_MODE2) /* mcasp0_ahclkr.mcasp0_axr2, OUTPUT | MODE2 */

0x1ac (PIN_INPUT_PULLDOWN | MUX_MODE2) /* mcasp0_ahclkx.mcasp0_axr3, INPUT | MODE2 */

};

mcasp0_pins_sleep: mcasp0_pins_sleep {

pinctrl-single,pins = <

0x190 (PIN_INPUT_PULLDOWN | MUX_MODE7)

0x194 (PIN_INPUT_PULLDOWN | MUX_MODE7)

0x19c (PIN_INPUT_PULLDOWN | MUX_MODE7)

0x1ac (PIN_INPUT_PULLDOWN | MUX_MODE7)

};

&i2c2 {

pinctrl-names = "default";

pinctrl-0 = <&i2c2_pins>;

status = "okay";

clock-frequency = <100000>;

//i2c device address:0x38

polytouch: edt-ft5x06@38 {

status = "okay";

compatible = "edt,edt-ft5x06";

pinctrl-names = "default";

pinctrl-0 = <&edt_ft5x06_ts_pins>;

reg = <0x38>;

interrupt-parent = <&gpio3>;

interrupts = <18 IRQ_TYPE_EDGE_FALLING>;

// reset-gpios = <&gpio3 18 GPIO_ACTIVE_LOW>;

// wake-gpios = <&gpio3 18 GPIO_ACTIVE_LOW>;

touchscreen-size-x = <800>;

touchscreen-size-y = <480>;

//touchscreen-inverted-x;

//touchscreen-swapped-x-y;

};

tlv320aic3106: tlv320aic3106@1b {

#sound-dai-cells = <0>;

compatible = "ti,tlv320aic3106";

reg = <0x1b>;

status = "okay";

/* Regulators */

AVDD-supply = <&ldo3_reg>;

IOVDD-supply = <&ldo3_reg>;

DRVDD-supply = <&ldo3_reg>;

DVDD-supply = <&dcdc1_reg>;

};

//顺便增加电源管理芯片

/include/ "tps65217.dtsi"

&tps {

regulators {

dcdc1_reg: regulator@0 {

// VDD_1V8 system supply

regulator-always-on;

};

dcdc2_reg: regulator@1 {

// VDD_CORE voltage limits 0.95V - 1.26V with +/-4% tolerance

regulator-name = "vdd_core";

regulator-min-microvolt = <925000>;

regulator-max-microvolt = <1150000>;

regulator-boot-on;

regulator-always-on;

};

dcdc3_reg: regulator@2 {

// VDD_MPU voltage limits 0.95V - 1.1V with +/-4% tolerance

regulator-name = "vdd_mpu";

regulator-min-microvolt = <925000>;

regulator-max-microvolt = <1325000>;

regulator-boot-on;

regulator-always-on;

};

ldo1_reg: regulator@3 {

// VRTC 1.8V always-on supply

regulator-name = "vrtc,vdds";

regulator-always-on;

};

ldo2_reg: regulator@4 {

// 3.3V rail

regulator-name = "vdd_3v3aux";

regulator-always-on;

};

ldo3_reg: regulator@5 {

// VDD_3V3A 3.3V rail

regulator-name = "vdd_3v3a";

regulator-min-microvolt = <3300000>;

regulator-max-microvolt = <3300000>;

};

ldo4_reg: regulator@6 {

// VDD_3V3B 3.3V rail

regulator-name = "vdd_3v3b";

regulator-always-on;

};

&mcasp0 {

#sound-dai-cells = <0>;

pinctrl-names = "default", "sleep";

pinctrl-0 = <&mcasp0_pins>;

pinctrl-1 = <&mcasp0_pins_sleep>;

status = "okay";

op-mode = <0>; /* MCASP_IIS_MODE */

tdm-slots = <2>;

/* 4 serializers */

serial-dir = < /* 0: INACTIVE, 1: TX, 2: RX */

0 0 1 2

tx-num-evt = <32>;

rx-num-evt = <32>;

};

增加按键驱动：

gpio_keys {

compatible = "gpio-keys";

pinctrl-names = "default";

pinctrl-0 = <&gpio_key_s0>;

#address-cells = <1>;

#size-cells = <0>;

button@1 {

debounce_interval = <50>;

linux,code = <105>;

label = "left";

gpios = <&gpio1 17 0x1>;

gpio-key,wakeup;

autorepeat;

};

button@2 {

debounce_interval = <50>;

linux,code = <106>;

label = "right";

gpios = <&gpio3 16 0x1>;

gpio-key,wakeup;

autorepeat;

};

button@3 {

debounce_interval = <50>;

linux,code = <103>;

label = "up";

gpios = <&gpio1 19 0x1>;

gpio-key,wakeup;

autorepeat;

};

button@4 {

debounce_interval = <50>;

linux,code = <108>;

label = "down";

gpios = <&gpio2 1 0x1>;

gpio-key,wakeup;

autorepeat;

};

button@5 {

debounce_interval = <50>;

linux,code = <28>;

label = "enter";

gpios = <&gpio0 3 0x1>;

gpio-key,wakeup;

};

button@6 {

debounce_interval = <50>;

linux,code = <1>;

label = "enter";

gpios = <&gpio0 5 0x1>;

gpio-key,wakeup;

};

button@9 {

debounce_interval = <50>;

linux,code = <115>;

label = "volume-up";

gpios = <&gpio0 2 0x1>;

gpio-key,wakeup;

autorepeat;

};

button@10 {

debounce_interval = <50>;

linux,code = <114>;

label = "volume-down";

gpios = <&gpio0 4 0x1>;

gpio-key,wakeup;

autorepeat;

};

每次更新驱动只需重新编译设备树文件即可,不必重新编译内核和模块，当然这里说的驱动只是在设备树上添加信息，真正的驱动代码还需要内核源文件的支持才可以，这可能是我下一步学习的重点了，还望大牛指正。

具体效果：

[media]http://player.youku.com/player.php/sid/XMzU4MTk2NjA3Ng==/v.swf[/media] 此内容由EEWORLD论坛网友anananjjj原创，如需转载或用于商业用途需征得作者同意并注明出处 本帖最后由 anananjjj 于 2018-5-4 07:41 编辑