基于Freescale Android4.2.2 max11801 的10寸电阻屏校准方法总结

作者：[e-mail]

时间：2014-5-6

 

关键字：Freescale , Android JB , max11801 , 电阻屏 , 校准

 

背景：

         当下，在Android4.2.2 上基本全部用的都是电容式的触摸屏了，所以Google和其他定制厂商也陆续在自己的Android版本中去掉了电阻屏校准这部分代码，飞思卡尔的Android 4.2.2也不例外，但在其Android 4.0.4上都还有ts_calibrator的电阻屏校准程序，我们下面的要介绍的方法就是把这个 ts_calibrator 移植到Android 4.2.2 上。

 

准备：

ts_calibrator.zip

max11801_ts.idc

<文件夹下还有相关改动文件的源文件，如果平台相同，可以偷懒哟>

 

移植步骤：

1、 将  ts_calibrator.zip 解包至  “${androidroot}/system/core/”  下。 
2、 修改  “${androidroot}/system/core/init/init.c” ,  参考如下

diff --git a/system/core/init/init.c b/system/core/init/init.cindex 8a4fc52..483391c 100755--- a/system/core/init/init.c+++ b/system/core/init/init.c@@ -77,6 +77,7 @@ static char bootmode[32]; static char hardware[32]; static unsigned revision = 0; static char qemu[32];+static char calibration;  #ifdef HAVE_SELINUX static int selinux_enabled = 1;@@ -623,8 +624,12 @@ static void import_kernel_nv(char *name, int for_emulator) {     char *value = strchr(name, '=');     int name_len = strlen(name);--    if (value == 0) return;+    /* zeng */+    if (value == 0) {+if (!strcmp(name, "calibration"))+    calibration = 1;+return;+    }     *value++ = 0;     if (name_len == 0) return; @@ -703,6 +708,11 @@ static void export_kernel_boot_props(void)         property_set("ro.factorytest", "2");     else         property_set("ro.factorytest", "0");+    /* zeng */+    if (calibration)+        property_set("ro.calibration", "1");+    else+        property_set("ro.calibration", "0"); }  static void process_kernel_cmdline(void)

3、修改  “${androidroot}/kernel_imx/”  下的文件，  参考如下 

diff --git a/kernel_imx/arch/arm/mach-mx6/board-mx6q_sabresd.c b/kernel_imx/arch/arm/mach-mx6/board-mx6q_sabresd.cindex f0d64a8..1946187 100644--- a/kernel_imx/arch/arm/mach-mx6/board-mx6q_sabresd.c+++ b/kernel_imx/arch/arm/mach-mx6/board-mx6q_sabresd.c@@ -201,7 +201,7 @@ static struct clk *sata_clk; static struct clk *clko; static int mma8451_position = 3; static int mag3110_position = 1;-static int max11801_mode = 1;+static int max11801_mode = 0; static int caam_enabled;  extern char *gp_reg_id;diff --git a/kernel_imx/drivers/input/touchscreen/max11801_ts.c b/kernel_imx/drivers/input/touchscreen/max11801_ts.cindex a1ac2d2..df27d15 100755--- a/kernel_imx/drivers/input/touchscreen/max11801_ts.c+++ b/kernel_imx/drivers/input/touchscreen/max11801_ts.c@@ -108,6 +108,18 @@ struct i2c_client *max11801_client; unsigned int max11801_workmode; u8 aux_buf[AUX_BUFSIZE]; +/**+ * calibration array refers to+ * (delta_x[0], delta_x[1], delta_x[2], delta_y[0], delta_y[1], delta_y[2], delta).+ * Which generated by calibration service.+ * In this driver when we got touch pointer (x', y') from PMIC ADC,+ * we calculate the display pointer (x,y) by:+ * x = (delta_x[0] * x' + delta_x[1] * y' + delta_x[2]) / delta;+ * y = (delta_y[0] * x' + delta_y[1] * y' + delta_y[2]) / delta;+ */+static int calibration[7];+module_param_array(calibration, int, NULL, S_IRUGO | S_IWUSR);+ static int max11801_dcm_write_command(struct i2c_client *client, int command) { return i2c_smbus_write_byte(client, command);@@ -169,9 +181,28 @@ static int max11801_write_reg(struct i2c_client *client, int addr, int data)  static void calibration_pointer(int *x_orig, int *y_orig) {-int  y;+int  x, y; y = MAX11801_MAX_Y - *y_orig; *y_orig = y;++if (calibration[6] != 0) {+x = calibration[0] * *x_orig ++calibration[1] * *y_orig ++calibration[2];+x /= calibration[6];+if (x < 0)+x = 0;+y = calibration[3] * *x_orig ++calibration[4] * *y_orig ++calibration[5];+y /= calibration[6];+if (y < 0)+y = 0;+*x_orig = x;+*y_orig = y;+}++/* printk("x: %d , y: %d\n", *x_orig, *y_orig); */ }  static irqreturn_t max11801_ts_interrupt(int irq, void *dev_id)

4、拷贝  max11801_ts.idc  到  “${androidroot}/device/fsl/common/input/”  ,  修改 “${androidroot}/device/fsl/”  下文件，参考如下 

diff --git a/device/fsl/imx6/etc/init.rc b/device/fsl/imx6/etc/init.rcindex 41e7995..ac56ad4 100755--- a/device/fsl/imx6/etc/init.rc+++ b/device/fsl/imx6/etc/init.rc@@ -398,6 +398,8 @@ on boot     setprop dalvik.vm.jniopts warnonly      class_start core+    class_start tscal+on property:service.calibrate.exit=1     class_start main  on property:sys.boot_completed=1@@ -544,6 +546,12 @@ service bootanim /system/bin/bootanimation     disabled     oneshot +service calibrate /system/bin/logwrapper /sbin/ts_calibrator+    class tscal+    user root+    group root+    oneshot+ service dbus /system/bin/dbus-daemon --system --nofork     class main     socket dbus stream 660 bluetooth bluetooth diff --git a/device/fsl/imx6/imx6.mk b/device/fsl/imx6/imx6.mkindex ac0ce25..c5438fb 100644--- a/device/fsl/imx6/imx6.mk+++ b/device/fsl/imx6/imx6.mk@@ -290,6 +290,7 @@ PRODUCT_COPY_FILES +=\ device/fsl/common/input/eGalax_Touch_Screen.idc:system/usr/idc/HannStar_P1003_Touchscreen.idc \ device/fsl/common/input/eGalax_Touch_Screen.idc:system/usr/idc/Novatek_NT11003_Touch_Screen.idc \ device/fsl/common/input/CTA_Touch_Screen.idc:system/usr/idc/CTA_Touch_Screen.idc \+device/fsl/common/input/max11801_ts.idc:system/usr/idc/max11801_ts.idc \ device/fsl/common/input/Vantron_CB_Keyboard.kl:system/usr/keylayout/gpio-keys.kl \ device/fsl/imx6/etc/init.rc:root/init.rc \ device/fsl/imx6/etc/apns-conf.xml:system/etc/apns-conf.xml \diff --git a/device/fsl/sabresd_6dq/BoardConfig.mk b/device/fsl/sabresd_6dq/BoardConfig.mkindex 716282b..b73f6fc 100755--- a/device/fsl/sabresd_6dq/BoardConfig.mk+++ b/device/fsl/sabresd_6dq/BoardConfig.mk@@ -93,7 +93,7 @@ $(error "TARGET_USERIMAGES_USE_UBIFS and TARGET_USERIMAGES_USE_EXT4 config open endif endif -BOARD_KERNEL_CMDLINE := console=ttymxc0,115200 init=/init video=mxcfb0:dev=ldb,CLAA070WP03,if=RGB666,fbpix=RGB32 ldb=sep1 video=mxcfb1:off video=mxcfb2:off fbmem=16M fb0base=0x27b00000 vmalloc=400M androidboot.console=ttymxc0 androidboot.hardware=freescale+BOARD_KERNEL_CMDLINE := calibration console=ttymxc0,115200 init=/init video=mxcfb0:dev=ldb,H101IV024,if=RGB666,fbpix=RGB32 ldb=sep1 video=mxcfb1:off video=mxcfb2:off fbmem=16M fb0base=0x27b00000 vmalloc=400M androidboot.console=ttymxc0 androidboot.hardware=freescale  ifeq ($(TARGET_USERIMAGES_USE_UBIFS),true) #UBI boot command line.@@ -117,6 +117,9 @@ NUM_FRAMEBUFFER_SURFACE_BUFFERS := 3  # agan PREBUILT_3G_MODEM_RIL :=true+# zeng+TARGET_TS_CALIBRATION :=true+TARGET_TS_DEVICE := "max11801_ts"  TARGET_BOOTLOADER_CONFIG := 6q:mx6q_sabresd_android_config 6dl:mx6dl_sabresd_android_config

在 ‘BOARD_KERNEL_CMDLINE ’中添加 ’ calibration ‘可开启ts_calibrator校准程序。

校准原理

ts_calibrator 校准后生成 /data/system/calibration，同时会拷贝到 /sys/module/max11801_ts/parameters/calibration，其中 /sys/module/max11801_ts/parameters/calibration中的参数又会传递给触摸屏驱动使用。

如下：

drivers/input/touchscreen/max11801_ts.c 修改部分中的module_param_array(calibration,int, NULL, S_IRUGO | S_IWUSR) 引用了/sys/module/max11801_ts/parameters/calibration中的参数。

 

注意事项

1、校准时要删除calibration文件

    rm /data/system/calibration

2、${androidroot} 为自己的android源码根目录

参考文档

imx53* 飞思卡尔 启用触摸屏校准