rk3568 Android11/12 适配 E-ink

“EINK”是英语ElectronicInk的缩写。翻译成中文为“电子墨水”。电子墨水由数百万个微胶囊(Microcapsules)所构成，微胶囊的大小约等同于人类头发的直径。每个微胶囊里含有电泳粒子──带负电荷的白色以及带正电荷的黑色粒子，悬浮于透明液体中。利用正负相吸的原理，当电场接通时，该区块对应的黑或白粒子会移动至微胶囊的顶端，使用者在该区块上，就能看见白色或黑色。

提示：E-ink 编译固件时需要匹配对应的源码中 ebook 工程。

圈重点 看想学

a) rk3568 适配 E-ink屏
b) 适配 E-ink屏问题

1. rk3568适配 E-ink屏

E-ink与LCD差别非常大，从显示原理到刷新机制，再到色彩范围应用场景；注定它是特殊领域的专用产品。

1.1 核查原理图，适配 E-ink屏

• E-ink 屏刷新时需要导入特殊的上电时许，要求比较严苛；需要外挂供电IC tps65185。
  
  详细查看原理图，梳理该电源芯片所使用GPIO映射关系如下：
  TPS65185 使用 I2C1；
  IRQ 占用 GPIO3_A7 高电平有效；
  wakeup 占用 GPIO3_C3 高电平有效；
  vcomctl 占用 GPIO4_B2 高电平有效；
  powerup 占用 GPIO4_C5 高电平有效；

• E-ink 在 rk3568 占用的功能模块
  

• E-ink排线接口
  

• E-ink 内核设备树适配 (以6英寸的eink屏为例)

/ {reserved-memory {#address-cells = <2>;#size-cells = <2>;ranges;waveform_reserved: waveform@10800000 {reg = <0x0 0x10800000 0x0 0x100000>;};display_reserved: framebuffer@10900000 {reg = <0x0 0x10900000 0x0 0x2c00000>;};};ebc_dev: ebc-dev {compatible = "rockchip,ebc-dev";ebc_tcon = <&ebc>;eink_tcon = <&eink>;memory-region = <&display_reserved>;waveform-region = <&waveform_reserved>;status = "okay";};
};&ebc {/* clock rate 1000M/n, (n=1~32) */assigned-clocks = <&cru CPLL_333M>, <&cru DCLK_EBC>;//assigned-clock-rates = <340000000>, <340000000>;assigned-clock-rates = <250000000>, <250000000>;//assigned-clock-rates = <100000000>, <100000000>;status = "okay";
};&eink {status = "okay";
};&ebc_dev {pmic = <&tps65185>;status = "okay";/* ED060XCD */panel,width = <1024>;panel,height = <758>;panel,vir_width = <1024>;panel,vir_height = <758>;panel,sdck = <20000000>;panel,lsl = <6>;panel,lbl = <6>;panel,ldl = <256>;panel,lel = <38>;panel,gdck-sta = <4>;panel,lgonl = <262>;panel,fsl = <2>;panel,fbl = <4>;panel,fdl = <758>;panel,fel = <5>;panel,mirror = <0>;panel,panel_16bit = <0>;panel,panel_color = <0>;panel,width-mm = <90>;panel,height-mm = <122>;
};&i2c1 {status = "okay";tps65185: tps65185@68 {status = "okay";compatible = "ti,tps65185";reg = <0x68>;pinctrl-names = "default";pinctrl-0 = <&tps65185_gpio>;int-gpios = <&gpio3 RK_PA7 GPIO_ACTIVE_HIGH>;wakeup-gpios = <&gpio3 RK_PC3 GPIO_ACTIVE_HIGH>;vcomctl-gpios = <&gpio4 RK_PB2 GPIO_ACTIVE_HIGH>;powerup-gpios = <&gpio4 RK_PC5 GPIO_ACTIVE_HIGH>;};
};&pinctrl {tps_pmic {tps65185_gpio: tps65185-gpio {rockchip,pins =<4 RK_PB2 RK_FUNC_GPIO &pcfg_pull_up>,<4 RK_PC5 RK_FUNC_GPIO &pcfg_pull_up>,<3 RK_PA7 RK_FUNC_GPIO &pcfg_pull_up>,<3 RK_PC3 RK_FUNC_GPIO &pcfg_pull_up>;};};
};

1.2 E-ink其它分辨率适配

硬件EBC所用接口相同，根据 DTS 规则只需要覆写分辨率属性即可。

• 9.7英寸 1200x825分辨 E-ink

&ebc_dev {pmic = <&tps65185>;status = "okay";/* ED097TC2U1 */panel,width = <1200>;panel,height = <825>;panel,vir_width = <1200>;panel,vir_height = <825>;panel,sdck = <25000000>;panel,lsl = <4>;panel,lbl = <4>;panel,ldl = <300>;panel,lel = <36>;panel,gdck-sta = <18>;panel,lgonl = <265>;panel,fsl = <2>;panel,fbl = <4>;panel,fdl = <825>;panel,fel = <24>;panel,mirror = <0>;panel,panel_16bit = <0>;panel,panel_color = <0>;panel,width-mm = <203>;panel,height-mm = <140>;

• 10.3英寸 1872x1404分辨 E-ink

&ebc_dev {pmic = <&tps65185>;status = "okay";/* ES103TC1 */panel,width = <1872>;panel,height = <1404>;panel,vir_width = <1872>;panel,vir_height = <1404>;panel,sdck = <33300000>;panel,lsl = <18>;panel,lbl = <17>;panel,ldl = <234>;panel,lel = <7>;panel,gdck-sta = <34>;panel,lgonl = <192>;panel,fsl = <1>;panel,fbl = <4>;panel,fdl = <1404>;panel,fel = <12>;panel,mirror = <0>;panel,panel_16bit = <1>;panel,panel_color = <0>;panel,width-mm = <157>;panel,height-mm = <210>;

• 13.3英寸 2208x1650分辨 E-ink

&ebc_dev {pmic = <&tps65185>;status = "okay";/* ES133TC1 */panel,width = <2200>;panel,height = <1650>;panel,vir_width = <2208>;panel,vir_height = <1650>;panel,sdck = <37500000>;panel,lsl = <4>;panel,lbl = <8>;panel,ldl = <275>;panel,lel = <14>;panel,gdck-sta = <34>;panel,lgonl = <217>;panel,fsl = <1>;panel,fbl = <4>;panel,fdl = <1650>;panel,fel = <6>;panel,mirror = <0>;panel,panel_16bit = <1>;panel,panel_color = <0>;panel,width-mm = <157>;panel,height-mm = <210>;

• 14英寸 2240x1680分辨 E-ink

&ebc_dev {pmic = <&tps65185>;status = "okay";panel,width = <2232>;panel,height = <1680>;panel,vir_width = <2240>;panel,vir_height = <1680>;panel,sdck = <33300000>;panel,lsl = <4>;panel,lbl = <8>;panel,ldl = <279>;panel,lel = <14>;panel,gdck-sta = <34>;panel,lgonl = <217>;panel,fsl = <1>;panel,fbl = <4>;panel,fdl = <1680>;panel,fel = <6>;panel,mirror = <0>;panel,panel_16bit = <1>;panel,panel_color = <0>;panel,width-mm = <157>;panel,height-mm = <210>;
};

ebc clk配置说明： 不同的屏，只需根据屏幕sdclk的值计算出ebc的clk rates填写到ebc节点中即可，16位屏计算公式ebc_dclk = sdclk * 8； 8位屏计算公式ebc_dclk = sdclk * 4; 以ES103TC1为例ebc_dclk= 33300000 * 8 = 266400000； 实际需求是266.4M,受限于其父时钟1000M，实际最多只能分配到250M，如下dts配置：

/* ES103TC1 */
&ebc {/* clock rate 1000M/n, (n=1~32) */assigned-clocks = <&cru CPLL_333M>, <&cru DCLK_EBC>;assigned-clock-rates = <250000000>, <250000000>;status = "okay";
};

1.3 waveform.img 和 vcom

刷写固件时需要烧录正确的 waveform.img 镜像，否则屏幕显示乱码或显示乱码。
除此之外，还有另一个参数vcom电压，每个屏幕都有一个对应的参数—vcom电压；这个数值与屏幕中标签相匹配，切忌刷入正确数值。

• vcom 电压确认
  可查看/sys/devices/platform/ebcdev/pmic_vcom确认是否正确。

# 查看vcom电压值,单位mV
cat /sys/devices/platform/ebcdev/pmic_vcom
1890
# 屏对标程vcom电压 -1.980V，写入方法如下
echo 1890 > /sys/devices/platform/ebcdev/pmic_vcom

• 波形文件确认

# 查看当前使用波形文件版本
cat /sys/devices/platform/ebc-dev/waveform_version

至此 E-ink屏内核适配基本完成。

2 E-ink 开机相关

2.1 开机过程logo相关图片

logo支持uboot kernel 阶段显示，充电动画和 logo所使用格式要求为bmp，并且要求该格式的图片分辨率与屏的分辨率一致，否则无法显示；系统在执行./mkimage.sh时会自动转换bmp格式的图片为灰度图。如果客户需要替换相关图片，请根据目录提示更新相关资源。在源码中对应文件夹：device/rockchip/rk356x/rk3566_eink/eink_logo

eink_logo/
├── android_logo
│   └── bootanimation.zip #Android 开机动画
├── kernel_logo
│   └── kernel.bmp # kernel logo
├── poweroff_logo
│   ├── poweroff_nopower.png # 低电量关机显示图片
│   └── poweroff.png # 关机显示图片
├── standby_logo
│   ├── standby_charge.png #充电休眠显示图片
│   ├── standby_lowpower.png #低电量休显示眠图片
│   └── standby.png #休眠显示图片
└── uboot_logo├── battery_0.bmp # 电量 ≥0% 且 ＜ 20%├── battery_1.bmp # 电量 ≥2% 且 ＜ 40%├── battery_2.bmp # 电量 ≥40% 且 ＜ 60%├── battery_3.bmp # 电量 ≥60% 且 ＜ 80%├── battery_4.bmp # 电量 ≥80% 且 ＜ 100%├── battery_5.bmp # 电量 100%├── battery_fail.bmp # uboot阶段电量过低，无法开机├── poweroff.bmp # uboot阶段关机显示图片└── uboot.bmp # uboot logo图片

以上为Android上层预置的待机、关机等相关图片资源，源码编译完成后会预置到板载系统的/vendor/media/。系统支持动态待机，关机图片，用户可以把相关图片存放到/data/misc/，系统优先加载该路径下的图片资源。如果用户资源图片不存在，则使用系统图片。用户预置资源图片格式为png，且分辨率与屏幕分辨率一致，否则显示异常（显示不全或乱码）。

用户关机图片 "/data/misc/poweroff.png"
用户低电关机显示图片 "/data/misc/poweroff_nopower.png"
用户待机显示图片 "/data/misc/standby.png"
用户待机低电显示图片 "/data/misc/standby_lowpower.png"
用户待机充电显示图片 "/data/misc/standby_charge.png"
系统关机显示图片 "/vendor/media/poweroff.png"
系统关机低电显示图片 "/vendor/media/poweroff_nopower.png"
系统待机显示图片 "/vendor/media/standby.png"
系统待机低电显示图片 "/vendor/media/standby_lowpower.png"
系统待机充电显示图片 "/vendor/media/standby_charge.png"

2.2 E-ink 刷新模式

E-ink 刷新模式可参考源码文档 RKDocs/common/Ebook/Rockchip_RK3566_Introduction_EBOOK_Display_Mode_CN.pdf。

Tips

1. rk3568 没有对应的工程示例，可参考rk3566_eink 和 rk3566_einkw6。
2. TPS658185 使用频繁，为避免受影响建议单独总线。
3. 电磁笔和触屏使用总线数据量比较庞大，建议分开且不与 tps65185共用。

总结

活学活用，做个合格的搬运工。