/************************************************************************
* I.MX6 Goodix GT9xx touchscreen driver porting
* 声明：
* 本文主要是记录GT9xx电容Touch移植过程中遇到的一些问题。
*
* 2016-1-27 深圳 南山平山村 曾剑锋
***********************************************************************/
一、参考文档：
GT9XX驱动移植说明书_for_Android_2014011401.pdf
二、error 1:
1. 出错信息：
1. 直接将驱动放在kernel里系统会卡死，出错信息如下：
USB Gadget resume begins
fsl_udc_resume, Wait for wakeup thread finishes
dr_controller_run: udc out low power mode
USB Gadget resume ends
fsl-usb2-udc: bind to driver android_usb
mousedev: PS/2 mouse device common for all mice
input: gpio-keys as /devices/platform/gpio-keys/input/input0
<<-GTP-INFO->> GTP driver installing...
<<-GTP-INFO->> GTP Driver Version: V2.4<2014/11/28>
<<-GTP-INFO->> GTP Driver Built@11:15:29, Jan 26 2016
<<-GTP-INFO->> GTP I2C Address: 0x5d
<<-GTP-INFO->> Guitar reset
<<-GTP-INFO->> Chip Type: GOODIX_GT9
<<-GTP-INFO->> IC Version: 9157_1040
<<-GTP-INFO->> X_MAX: 720, Y_MAX: 1280, TRIGGER: 0x01
<<-GTP-INFO->> create proc entry gt9xx_config success
input: goodix-ts as /devices/virtual/input/input1
<<-GTP-INFO->> GTP works in interrupt mode.
<<-GTP-INFO->> Applied memory size:2562.
<<-GTP-INFO->> Applied memory size:2562.
<<-GTP-INFO->> I2C function: without pre and end cmd!
<<-GTP-INFO->> Create proc entry success!
mtk_tpd: hotknot_device register failed
USB Gadget resume begins
fsl_udc_resume, Wait for wakeup thread finishes
ehci_fsl_bus_suspend begins, Host 1
ehci_fsl_bus_suspend ends, Host 1
<系统会卡死在这里，接下来没有任何信息输出>
2. 作为模块加入内核，使用久了，系统也会卡死：
root@android:/ # cd /data/local
root@android:/data/local # ls
gt9xxm.ko
tmp
root@android:/data/local # insmod gt9xxm.ko
<<-GTP-INFO->> GTP driver installing...
<<-GTP-INFO->> GTP Driver Version: V2.4<2014/11/28>
<<-GTP-INFO->> GTP Driver Built@11:40:19, Jan 26 2016
<<-GTP-INFO->> GTP I2C Address: 0x5d
<<-GTP-INFO->> Guitar reset
<<-GTP-INFO->> Chip Type: GOODIX_GT9
<<-GTP-INFO->> IC Version: 9157_1040
<<-GTP-INFO->> X_MAX: 720, Y_MAX: 1280, TRIGGER: 0x01
<<-GTP-INFO->> create proc entry gt9xx_config success
input: goodix-ts as /devices/virtual/input/input1
cpufreq_interactive_input_connect: connect to goodix-ts
<<-GTP-INFO->> GTP works in interrupt mode.
<<-GTP-INFO->> Applied memory size:2562.
<<-GTP-INFO->> Applied memory size:2562.
<<-GTP-INFO->> I2C function: without pre and end cmd!
root@android:/data/local # <<-GTP-INFO->> Create proc entry success!
mtk_tpd: hotknot_device register failed
2. 解决方法：
1. cat gt9xx.h
......
#define HOTKNOT_ENABLE 0 // hotknot module
#define HOTKNOT_BLOCK_RW 0 // block rw operation in hotknot
......
2. cat goodix_tool.c
s32 init_wr_node(struct i2c_client *client)
{
......
#if 0
if (misc_register(&hotknot_misc_device))
{
printk("mtk_tpd: hotknot_device register failed\n");
return FAIL;
}
#endif
......
}
3. 思路来源：
1. 想通过尽可能减少驱动的功能来判断驱动哪里出了问题。
2. cat gt9xx.h
......
#define HOTKNOT_ENABLE 1 // hotknot module
#define HOTKNOT_BLOCK_RW 1 // block rw operation in hotknot
......
3. 如上所述，不需要该功能，当然我也不知道这是什么功能。
4. 改为如下内容：
#define HOTKNOT_ENABLE 0 // hotknot module
#define HOTKNOT_BLOCK_RW 0 // block rw operation in hotknot
5. 报错如下：
......
CC drivers/input/touchscreen/gt9xx.o
drivers/input/touchscreen/gt9xx.c: In function 'goodix_ts_suspend':
drivers/input/touchscreen/gt9xx.c:2735:5: warning: unused variable 'buf' [-Wunused-variable]
CC drivers/input/touchscreen/gt9xx_update.o
CC drivers/input/touchscreen/goodix_tool.o
drivers/input/touchscreen/goodix_tool.c: In function 'init_wr_node':
drivers/input/touchscreen/goodix_tool.c:346:21: error: 'hotknot_misc_device' undeclared (first use in this function)
drivers/input/touchscreen/goodix_tool.c:346:21: note: each undeclared identifier is reported only once for each function it appears in
drivers/input/touchscreen/goodix_tool.c: At top level:
drivers/input/touchscreen/goodix_tool.c:855:16: warning: 'hotknot_write' defined but not used [-Wunused-function]
drivers/input/touchscreen/goodix_tool.c:1243:16: warning: 'hotknot_read' defined but not used [-Wunused-function]
make[3]: *** [drivers/input/touchscreen/goodix_tool.o] Error 1
make[2]: *** [drivers/input/touchscreen] Error 2
make[1]: *** [drivers/input] Error 2
make: *** [drivers] Error 2
error: make uImage failed.
./remake.sh: 18: exit: Illegal number: -1
6. 既然已经禁止了，那么不可能还有hotknot_misc_device设备注册的，也就意味着这个版本的驱动有错。
7. 综上所述：可能是我们的kernel不支持hotknot这个功能导致的。
三、error 2:
1. 触摸屏点击有效，但是不准确，TP厂没有给矫正文件，后来FAE确认是由于矫正配置参数的问题。
2. 修改gt9xx.h文件：
......
#define GTP_DRIVER_SEND_CFG 1
......
3. 配置参数：
#define CTP_CFG_GROUP0 {\
0x46,0xD0,0x02,0x00,0x05,0x0A,0x05,0x40,0x01,0x08,\
0x28,0x0F,0x50,0x32,0x03,0x05,0x00,0x00,0x00,0x00,\
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x8A,0x0A,0x0B,\
0x2E,0x30,0x31,0x0D,0x00,0x00,0x00,0x02,0x03,0x1D,\
0x00,0x01,0x00,0x00,0x00,0x00,0x00,0x32,0x00,0x00,\
0x00,0x21,0x41,0x94,0xC5,0x02,0x07,0x00,0x00,0x04,\
0x9E,0x23,0x00,0x8D,0x28,0x00,0x80,0x2E,0x00,0x74,\
0x35,0x00,0x69,0x3C,0x00,0x69,0x00,0x00,0x00,0x00,\
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,\
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,\
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,\
0x00,0x00,0x16,0x14,0x12,0x10,0x0E,0x0C,0x0A,0x08,\
0x06,0x04,0x02,0xFF,0xFF,0xFF,0x00,0x00,0x00,0x00,\
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,\
0x00,0x00,0x16,0x13,0x18,0x12,0x1C,0x10,0x1D,0x0F,\
0x0A,0x1E,0x00,0x24,0x22,0x02,0x21,0x04,0x20,0x06,\
0x1F,0x08,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x00,0x00,\
0x00,0xFB,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,\
0x9F,0xFF,0xFF,0xFF,0x00,0x01\
}
