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----------------------------------------------------------------------------------------------------------------------------内核版本：linux 5.2.8根文件系统：busybox 1.25.0u-boot：2016.05---------------------------------------------------------------------------------------------------------------------------- 在上一节我们已经移植了LCD驱动，那么本节将会移植LCD触摸屏驱动。有关触摸屏的原理，以及硬件接线，我们在linux驱动移植-LCD触摸屏设备驱动章节已经介绍的非常清楚了。同时在这一篇博客，我们也详细介绍了触摸屏驱动的实现，并进行了代码演示。 linux 5.2.8内核已经自带了s3c2440触摸屏驱动，该驱动还依赖于ADC驱动，相当于把我们在linux驱动移植-LCD触摸屏设备驱动中写的驱动程序拆成了两个部分，但是代码整体逻辑大致是一样的。 这一节，我们将尝试引入设备树，通过设备树来实现触摸屏驱动程序。 一、触摸屏驱动linux 5.2.8自带的s3c2440触摸屏驱动，其采用platform设备驱动模型。 1.1 platform device名字为"s3c2410-ts"的platform device定义在arch/arm/plat-samsung/devs.c文件： static struct resource s3c_ts_resource[] = { [0] = DEFINE_RES_MEM(S3C24XX_PA_ADC, S3C24XX_SZ_ADC), // 0x58000000 SZ_1M [1] = DEFINE_RES_IRQ(IRQ_TC), // IRQ_TC为子中断 子中断控制器硬件中断号9，对应的主中断控制器硬件中断号31 }; struct platform_device s3c_device_ts = { .name = "s3c2410-ts", .id = -1, .dev.parent = &s3c_device_adc.dev, .num_resources = ARRAY_SIZE(s3c_ts_resource), .resource = s3c_ts_resource, }; void __init s3c24xx_ts_set_platdata(struct s3c2410_ts_mach_info *hard_s3c2410ts_info) { s3c_set_platdata(hard_s3c2410ts_info, sizeof(struct s3c2410_ts_mach_info), &s3c_device_ts); }其中函数s3c24xx_ts_set_platdata用于设置platform设备的私有数据，数据类型为struct s3c2410_ts_mach_info，s3c_device_ts.dev.platform_data会被设置为&default_ts_data ： static struct s3c2410_ts_mach_info default_ts_data __initdata = { .delay = 10000, .presc = 49, .oversampling_shift = 2, }; default_ts_data定义在arch/arm/plat-samsung/devs.c文件中的，我们需要把s3c_device_ts成员里初始化的这些常量数据抽离到设备树中。 1.2 platform driver名字为"s3c2410-ts"的platform driver定义在drivers/input/touchscreen/s3c2410_ts.c文件： static const struct dev_pm_ops s3c_ts_pmops = { .suspend = s3c2410ts_suspend, .resume = s3c2410ts_resume, }; #endif static const struct platform_device_id s3cts_driver_ids[] = { { "s3c2410-ts", 0 }, { "s3c2440-ts", 0 }, { "s3c64xx-ts", FEAT_PEN_IRQ }, { } }; MODULE_DEVICE_TABLE(platform, s3cts_driver_ids); static struct platform_driver s3c_ts_driver = { .driver = { .name = "samsung-ts", #ifdef CONFIG_PM .pm = &s3c_ts_pmops, #endif }, .id_table = s3cts_driver_ids, .probe = s3c2410ts_probe, .remove = s3c2410ts_remove, }; module_platform_driver(s3c_ts_driver); 1.3 s3c2410ts_probe当platform设备和驱动匹配后，将会调用s3c2410ts_probe进行input设备的注册。函数定义在drivers/input/touchscreen/s3c2410_ts.c：  
/**
* s3c2410ts_probe - device core probe entry point
* @pdev: The device we are being bound to.
*
* Initialise, find and allocate any resources we need to run and then
* register with the ADC and input systems.
*/
static int s3c2410ts_probe(struct platform_device *pdev)
{
struct s3c2410_ts_mach_info *info;
struct device *dev = &pdev->dev;
struct input_dev *input_dev;
struct resource *res;
int ret = -EINVAL;
/* Initialise input stuff */
memset(&ts, 0, sizeof(struct s3c2410ts));
ts.dev = dev;
info = dev_get_platdata(dev);
if (!info) {
dev_err(dev, "no platform data, cannot attach\n");
return -EINVAL;
}
dev_dbg(dev, "initialising touchscreen\n");
ts.clock = clk_get(dev, "adc");
if (IS_ERR(ts.clock)) {
dev_err(dev, "cannot get adc clock source\n");
return -ENOENT;
}
ret = clk_prepare_enable(ts.clock);
if (ret) {
dev_err(dev, "Failed! to enabled clocks\n");
goto err_clk_get;
}
dev_dbg(dev, "got and enabled clocks\n");
ts.irq_tc = ret = platform_get_irq(pdev, 0);
if (ret < 0) {
dev_err(dev, "no resource for interrupt\n");
goto err_clk;
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
dev_err(dev, "no resource for registers\n");
ret = -ENOENT;
goto err_clk;
}
ts.io = ioremap(res->start, resource_size(res));
if (ts.io == NULL) {
dev_err(dev, "cannot map registers\n");
ret = -ENOMEM;
goto err_clk;
}
/* inititalise the gpio */
if (info->cfg_gpio)
info->cfg_gpio(to_platform_device(ts.dev));
ts.client = s3c_adc_register(pdev, s3c24xx_ts_select,
s3c24xx_ts_conversion, 1);
if (IS_ERR(ts.client)) {
dev_err(dev, "failed to register adc client\n");
ret = PTR_ERR(ts.client);
goto err_iomap;
}
/* Initialise registers */
if ((info->delay & 0xffff) > 0)
writel(info->delay & 0xffff, ts.io + S3C2410_ADCDLY);
writel(WAIT4INT | INT_DOWN, ts.io + S3C2410_ADCTSC);
input_dev = input_allocate_device();
if (!input_dev) {
dev_err(dev, "Unable to allocate the input device !!\n");
ret = -ENOMEM;
goto err_iomap;
}
ts.input = input_dev;
ts.input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
ts.input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
input_set_abs_params(ts.input, ABS_X, 0, 0x3FF, 0, 0);
input_set_abs_params(ts.input, ABS_Y, 0, 0x3FF, 0, 0);
ts.input->name = "S3C24XX TouchScreen";
ts.input->id.bustype = BUS_HOST;
ts.input->id.vendor = 0xDEAD;
ts.input->id.product = 0xBEEF;
ts.input->id.version = 0x0102;
ts.shift = info->oversampling_shift;
ts.features = platform_get_device_id(pdev)->driver_data;
ret = request_irq(ts.irq_tc, stylus_irq, 0,
"s3c2410_ts_pen", ts.input);
if (ret) {
dev_err(dev, "cannot get TC interrupt\n");
goto err_inputdev;
}
dev_info(dev, "driver attached, registering input device\n");
/* All went ok, so register to the input system */
ret = input_register_device(ts.input);
if (ret < 0) {
dev_err(dev, "failed to register input device\n");
ret = -EIO;
goto err_tcirq;
}
return 0;
err_tcirq:
free_irq(ts.irq_tc, ts.input);
err_inputdev:
input_free_device(ts.input);
err_iomap:
iounmap(ts.io);
err_clk:
clk_disable_unprepare(ts.clock);
del_timer_sync(&touch_timer);
err_clk_get:
clk_put(ts.clock);
return ret;
}
View Code
全局变量ts定义如下： #define TSC_SLEEP (S3C2410_ADCTSC_PULL_UP_DISABLE | S3C2410_ADCTSC_XY_PST(0)) #define INT_DOWN (0) #define INT_UP (1 dev; struct adc_device *adc; struct resource *regs; enum s3c_cpu_type cpu = platform_get_device_id(pdev)->driver_data; int ret; unsigned tmp; adc = devm_kzalloc(dev, sizeof(*adc), GFP_KERNEL); if (!adc) return -ENOMEM; spin_lock_init(&adc->lock); adc->pdev = pdev; adc->prescale = S3C2410_ADCCON_PRSCVL(49); adc->vdd = devm_regulator_get(dev, "vdd"); if (IS_ERR(adc->vdd)) { dev_err(dev, "operating without regulator \"vdd\" .\n"); return PTR_ERR(adc->vdd); } adc->irq = platform_get_irq(pdev, 1); if (adc->irq irq, s3c_adc_irq, 0, dev_name(dev), adc); if (ret < 0) { dev_err(dev, "failed to attach adc irq\n"); return ret; } adc->clk = devm_clk_get(dev, "adc"); if (IS_ERR(adc->clk)) { dev_err(dev, "failed to get adc clock\n"); return PTR_ERR(adc->clk); } regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); adc->regs = devm_ioremap_resource(dev, regs); if (IS_ERR(adc->regs)) return PTR_ERR(adc->regs); ret = regulator_enable(adc->vdd); if (ret) return ret; clk_prepare_enable(adc->clk); tmp = adc->prescale | S3C2410_ADCCON_PRSCEN; /* Enable 12-bit ADC resolution */ if (cpu == TYPE_ADCV12) tmp |= S3C2416_ADCCON_RESSEL; if (cpu == TYPE_ADCV2 || cpu == TYPE_ADCV3) tmp |= S3C64XX_ADCCON_RESSEL; writel(tmp, adc->regs + S3C2410_ADCCON); dev_info(dev, "attached adc driver\n"); platform_set_drvdata(pdev, adc); adc_dev = adc; return 0; } View Code 三、修改驱动程序由于linux 5.2.8已经自带了s3c2440触摸屏、以及ADC驱动，因此我们直接在内核源码上改造，使其支持设备树即可。 3.1 修改设备树 3.1.1 新增myts设备节点在内核arch/arm/boot/dts/s3c2440-smdk2440.dts文件中添加myts设备节点，用于触摸屏驱动： myts: myts@5800000 { compatible = "myts"; reg = ; reg-names = "adc_ts_physical"; interrupts = ; interrupt-names = "int_tc"; clocks = ; clock-names = "adc"; delay = ; presc = ; oversampling_shift = ; }; 3.1.2 新增myadc设备节点在内核arch/arm/boot/dts/s3c2440-smdk2440.dts文件中添加myadc设备节点，用于ADC驱动： myadc: myadc@5800000 { compatible = "myadc"; reg = ; reg-names = "adc_physical"; interrupts = ,; interrupt-names = "int_tc","int_adc_s"; clocks = ; clock-names = "adc"; }; 3.2 修改触摸屏驱动 3.2.1 修改s3c_ts_driver为了支持设备树，所以我们需要修改s3c_ts_driver变量添加设备树匹配项，变量定义在arch/arm/plat-samsung/devs.c文件。修改完成后代码如下： static const struct dev_pm_ops s3c_ts_pmops = { .suspend = s3c2410ts_suspend, .resume = s3c2410ts_resume, }; #endif static const struct of_device_id s3cts_dt_match[] = { // 用于设备树匹配 { .compatible = "myts", .data = (void *)0 }, {}, }; static const struct platform_device_id s3cts_driver_ids[] = { { "s3c2410-ts", 0 }, { "s3c2440-ts", 0 }, { "s3c64xx-ts", FEAT_PEN_IRQ }, { } }; MODULE_DEVICE_TABLE(platform, s3cts_driver_ids); static struct platform_driver s3c_ts_driver = { .driver = { .name = "samsung-ts", .of_match_table = of_match_ptr(s3cts_dt_match), #ifdef CONFIG_PM .pm = &s3c_ts_pmops, #endif }, .id_table = s3cts_driver_ids, .probe = s3c2410ts_probe, .remove = s3c2410ts_remove, }; 3.2.2 修改s3c2410ts_probe当platform设备和驱动匹配后，将会调用s3c2410ts_probe进行input设备的注册，函数位于drivers/input/touchscreen/s3c2410_ts.c文件，修改完之后代码如下： /** * s3c2410ts_probe - device core probe entry point * @pdev: The device we are being bound to. * * Initialise, find and allocate any resources we need to run and then * register with the ADC and input systems. */ static int s3c2410ts_probe(struct platform_device *pdev) { struct s3c2410_ts_mach_info *info; struct device *dev = &pdev->dev; struct input_dev *input_dev; struct resource *res; int ret = -EINVAL; struct device_node *np; np = dev->of_node; // 获取myts设备节点 if (!np) { dev_err(dev, "could not find device info\n"); return -EINVAL; } /* Initialise input stuff */ memset(&ts, 0, sizeof(struct s3c2410ts)); ts.dev = dev; info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL); // 动态分配struct s3c2410_ts_mach_info if (!info) { dev_err(dev, "no mem for info\n"); return -ENOMEM; } // 获取设备节点中的各个属性值，用来设置驱动参数 of_property_read_u32(np, "delay", &info->delay); of_property_read_u32(np, "presc", &info->presc); of_property_read_u32(np, "oversampling_shift", &info->oversampling_shift); dev_dbg(dev, "%s: delay: 0x%lx\n", __func__, info->delay); dev_dbg(dev, "%s: presc: 0x%1x\n", __func__, info->presc); dev_dbg(dev, "%s: oversampling_shift: 0x%1x\n", __func__, info->oversampling_shift); dev_dbg(dev, "initialising touchscreen\n"); ts.clock = clk_get(dev, "adc"); // 获取adc时钟 if (IS_ERR(ts.clock)) { dev_err(dev, "cannot get adc clock source\n"); return -ENOENT; } ret = clk_prepare_enable(ts.clock); // 使能时钟 if (ret) { dev_err(dev, "Failed! to enabled clocks\n"); goto err_clk_get; } dev_dbg(dev, "got and enabled clocks\n"); ts.irq_tc = ret = platform_get_irq(pdev, 0); // 获取第一个IRQ编号 if (ret < 0) { dev_err(dev, "no resource for interrupt\n"); goto err_clk; } res = platform_get_resource(pdev, IORESOURCE_MEM, 0); // 获取第一个内存资源 if (!res) { dev_err(dev, "no resource for registers\n"); ret = -ENOENT; goto err_clk; } ts.io = ioremap(res->start, resource_size(res)); // 将ADC相关寄存器起始物理地址映射到虚拟地址，并返回虚拟地址 if (ts.io == NULL) { dev_err(dev, "cannot map registers\n"); ret = -ENOMEM; goto err_clk; } /* inititalise the gpio */ if (info->cfg_gpio) info->cfg_gpio(to_platform_device(ts.dev)); ts.client = s3c_adc_register(pdev, s3c24xx_ts_select, s3c24xx_ts_conversion, 1); if (IS_ERR(ts.client)) { dev_err(dev, "failed to register adc client\n"); ret = PTR_ERR(ts.client); goto err_iomap; } /* Initialise registers */ if ((info->delay & 0xffff) > 0) writel(info->delay & 0xffff, ts.io + S3C2410_ADCDLY); // 设置ADC启动延时时间 writel(WAIT4INT | INT_DOWN, ts.io + S3C2410_ADCTSC); // 设置ADCTSC 1 evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); // 支持按键事件 支持绝对位移事件 ts.input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); // 触摸屏笔尖按下 input_set_abs_params(ts.input, ABS_X, 0, 0x3FF, 0, 0); // s3c2440手册ADC是10位，所以第四个参数设置为0x3FF input_set_abs_params(ts.input, ABS_Y, 0, 0x3FF, 0, 0); // s3c2440手册ADC是10位，所以第四个参数设置为0x3FF ts.input->name = "S3C24XX TouchScreen"; ts.input->id.bustype = BUS_HOST; ts.input->id.vendor = 0xDEAD; ts.input->id.product = 0xBEEF; ts.input->id.version = 0x0102; ts.shift = info->oversampling_shift; //ts.features = platform_get_device_id(pdev)->driver_data; ts.features = of_device_get_match_data(&pdev->dev); // 获取私有数据 ret = request_irq(ts.irq_tc, stylus_irq, 0, // 申请中断 "s3c2410_ts_pen", ts.input); if (ret) { dev_err(dev, "cannot get TC interrupt\n"); goto err_inputdev; } dev_info(dev, "driver attached, registering input device\n"); /* All went ok, so register to the input system */ ret = input_register_device(ts.input); // 注册input_dev if (ret < 0) { dev_err(dev, "failed to register input device\n"); ret = -EIO; goto err_tcirq; } return 0; err_tcirq: free_irq(ts.irq_tc, ts.input); err_inputdev: input_free_device(ts.input); err_iomap: iounmap(ts.io); err_clk: clk_disable_unprepare(ts.clock); del_timer_sync(&touch_timer); err_clk_get: clk_put(ts.clock); return ret; }同时需要引入头文件： #include 3.3 修改ADC驱动 3.3.1 修改s3c_adc_driver为了支持设备树，所以我们需要修改s3c_adc_driver变量添加设备树匹配项，变量定义在arch/arm/plat-samsung/adc.c文件。修改完成后代码如下： static const struct of_device_id s3c_adc_dt_match[] = { // 用于设备树匹配 { .compatible = "myadc", .data = (void *)TYPE_ADCV1 }, {}, }; static const struct platform_device_id s3c_adc_driver_ids[] = { { .name = "s3c24xx-adc", .driver_data = TYPE_ADCV1, }, { .name = "s3c2443-adc", .driver_data = TYPE_ADCV11, }, { .name = "s3c2416-adc", .driver_data = TYPE_ADCV12, }, { .name = "s3c64xx-adc", .driver_data = TYPE_ADCV2, }, { .name = "samsung-adc-v3", .driver_data = TYPE_ADCV3, }, { } }; MODULE_DEVICE_TABLE(platform, s3c_adc_driver_ids); static const struct dev_pm_ops adc_pm_ops = { .suspend = s3c_adc_suspend, .resume = s3c_adc_resume, }; static struct platform_driver s3c_adc_driver = { .id_table = s3c_adc_driver_ids, .driver = { .name = "s3c-adc", .of_match_table = of_match_ptr(s3c_adc_dt_match), .pm = &adc_pm_ops, }, .probe = s3c_adc_probe, .remove = s3c_adc_remove, }; 3.3.2 修改s3c_adc_probe当platform设备和驱动匹配后，将会调用s3c_adc_probe进行ADD相关的初始化工作。函数位于arch/arm/plat-samsung/adc.c文件，修改完之后代码如下： static int s3c_adc_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct adc_device *adc; struct resource *regs; //enum s3c_cpu_type cpu = platform_get_device_id(pdev)->driver_data; enum s3c_cpu_type cpu = (int)of_device_get_match_data(&pdev->dev); // 获取私有数据 int ret; unsigned tmp; adc = devm_kzalloc(dev, sizeof(*adc), GFP_KERNEL); if (!adc) return -ENOMEM; spin_lock_init(&adc->lock); adc->pdev = pdev; adc->prescale = S3C2410_ADCCON_PRSCVL(49); // 设置预分频器的值 (49&0xff) vdd = devm_regulator_get(dev, "vdd"); if (IS_ERR(adc->vdd)) { dev_err(dev, "operating without regulator \"vdd\" .\n"); return PTR_ERR(adc->vdd); } adc->irq = platform_get_irq(pdev, 1); // 获取第2个IRQ编号 IRQ_ADC ADC转换成功后，会进入IRQ_ADC中断函数 if (adc->irq irq, s3c_adc_irq, 0, dev_name(dev), // 申请中断 adc); if (ret < 0) { dev_err(dev, "failed to attach adc irq\n"); return ret; } adc->clk = devm_clk_get(dev, "adc"); // 获取adc时钟 if (IS_ERR(adc->clk)) { dev_err(dev, "failed to get adc clock\n"); return PTR_ERR(adc->clk); } regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); // 获取第一个内存资源 ADC相关寄存器基地址 adc->regs = devm_ioremap_resource(dev, regs); // 将ADC相关寄存器起始物理地址映射到虚拟地址，并返回虚拟地址 if (IS_ERR(adc->regs)) return PTR_ERR(adc->regs); ret = regulator_enable(adc->vdd); if (ret) return ret; clk_prepare_enable(adc->clk); // 使能时钟 tmp = adc->prescale | S3C2410_ADCCON_PRSCEN; // 49 pdev)->driver_data;全部修改为： enum s3c_cpu_type cpu = (int)of_device_get_match_data(&pdev->dev); // 获取私有数据 四、烧录开发板测试 4.1 配置内核执行如下命令： root@zhengyang:/work/sambashare/linux-5.2.8-dt# make menuconfig配置内核，将内核自带的触摸屏驱动编译进内核： Device Drivers ---> Input device support --> [*] Touchscreens --> Samsung S3C2410/generic touchscreen input driver Graphics support ---> [ ] Bootup logo --->保存文件，输入文件名s3c2440_defconfig，在当前路径下生成s3c2440_defconfig：存档： root@zhengyang:/work/sambashare/linux-5.2.8-dt# mv s3c2440_defconfig ./arch/arm/configs/ 4.2 编译内核此时重新执行： root@zhengyang:/work/sambashare/linux-5.2.8-dt# make distclean root@zhengyang:/work/sambashare/linux-5.2.8-dt# make s3c2440_defconfig root@zhengyang:/work/sambashare/linux-5.2.8-dt# make uImage V=1将uImage复制到tftp服务器路径下：、 root@zhengyang:/work/sambashare/linux-5.2.8-dt# cp /work/sambashare/linux-5.2.8-dt/arch/arm/boot/uImage /work/tftpboot/ 4.3 编译dts在linux内核根目录执行如下命令： root@zhengyang:/work/sambashare/linux-5.2.8-dt# make dtbs DTC arch/arm/boot/dts/s3c2416-smdk2416.dtb DTC arch/arm/boot/dts/s3c2440-smdk2440.dtb编译设备树文件，把前面配置过的arch/arm/boot/dts里的dts文件编译成dtb文件。 将s3c2440-smdk2440.dtb复制到tftp服务器路径下： root@zhengyang:/work/sambashare/linux-5.2.8-dt# cp /work/sambashare/linux-5.2.8-dt/arch/arm/boot/dts/s3c2440-smdk2440.dtb /work/tftpboot/ 4.4 启动内核uboot启动后，将dtb下载到内存地址0x30001000中： SMDK2440 # tftp 0x30001000 s3c2440-smdk2440.dtb注意：我们可以修改uboot源码，扩展一个device_tree分区，然后将dtb文件存储在该分区中。 然后将内核镜像加载到内存0x30008000地址，并烧录内核到Nand Flash： SMDK2440 # tftp 30008000 uImage SMDK2440 # nand erase.part kernel SMDK2440 # nand write 30008000 kernel然后可以使用如下命令启动内核： SMDK2440 # bootm 0x30008000 - 0x30001000 // 无设备树时，直接bootm 0x30008000 //bootm uImage地址 ramdisk地址 设备树镜像地址内核启动打印有关LCD触摸屏信息如下： .... samsung-ts 58000000.myts: no pinctrl handle OF: no dma-ranges found for node(/myts@5800000) samsung-ts 58000000.myts: device is not dma coherent samsung-ts 58000000.myts: device is not behind an iommu samsung-ts 58000000.myts: s3c2410ts_probe: delay: 0xffff samsung-ts 58000000.myts: s3c2410ts_probe: presc: 0x31 samsung-ts 58000000.myts: s3c2410ts_probe: oversampling_shift: 0x2 samsung-ts 58000000.myts: initialising touchscreen clock-names adc in index 0 samsung-ts 58000000.myts: got and enabled clocks OF: of_irq_parse_one: dev=/myts@5800000, index=0 OF: parent=/interrupt-controller@4a000000, intsize=4 OF: intspec=1 of_irq_parse_raw: /interrupt-controller@4a000000:00000001,0000001f,00000009,00000003 OF: of_irq_parse_raw: ipar=/interrupt-controller@4a000000, size=4 OF: -> addrsize=1 OF: -> got it ! samsung-ts 58000000.myts: driver attached, registering input device PM: Adding info for No Bus:input0 input: S3C24XX TouchScreen as /devices/virtual/input/input0 ....内核启动打印有关ADC信息如下： .... s3c-adc 58000000.myadc: no pinctrl handle OF: no dma-ranges found for node(/myadc@5800000) s3c-adc 58000000.myadc: device is not dma coherent s3c-adc 58000000.myadc: device is not behind an iommu OF: of_irq_parse_one: dev=/myadc@5800000, index=1 OF: parent=/interrupt-controller@4a000000, intsize=4 OF: intspec=1 of_irq_parse_raw: /interrupt-controller@4a000000:00000001,0000001f,0000000a,00000003 OF: of_irq_parse_raw: ipar=/interrupt-controller@4a000000, size=4 OF: -> addrsize=1 OF: -> got it ! clock-names adc in index 0 s3c-adc 58000000.myadc: attached adc driver ....运行命令cat /proc/interrupts可以查看当前系统有哪些中断服务： [root@zy:/]# cat /proc/interrupts CPU0 7: 1304 s3c-eint 7 Edge eth0 8: 0 s3c 8 Edge s3c2410-rtc tick 13: 10445 s3c 13 Edge samsung_time_irq 22: 0 s3c 16 Edge 4d000000.fb 27: 0 s3c 27 Edge 54000000.i2c 30: 0 s3c 30 Edge s3c2410-rtc alarm 35: 8 s3c-level 35 Level 50004000.serial 36: 56 s3c-level 36 Level 50004000.serial 41: 0 s3c-level 41 Edge s3c2410_ts_pen // IRQ_TC 42: 0 s3c-level 42 Edge 58000000.myadc // IRQ_ADC 59: 0 s3c-level 59 Edge 53000000.watchdog查看设备节点文件： [root@zy:/]# ls /dev/input -l total 0 crw-rw---- 1 0 0 13, 64 Jan 1 00:00 event0 五、使用tslib进行测试 5.1 下载tslib直接到github上下载： root@zhengyang:/work/sambashare/drivers/#git clone https://github.com/kergoth/tslib下载完成后，我直接上传到ubuntu服务器如下路径：/work/sambashare/drivers。 跳转到tslib文件夹： root@zhengyang:/work/sambashare/drivers# cd tslib/ 5.2 编译首先运行： root@zhengyang:/work/sambashare/drivers/tslib# ./autogen.sh root@zhengyang:/work/sambashare/drivers/tslib# mkdir tmp然后配置： root@zhengyang:/work/sambashare/drivers/tslib# CC=arm-linux-gcc ./configure --host=arm-linux --cache-file=arm-linux.cache --prefix=$(pwd)/tmp CFLAGS="-march=armv4t -O2 -Wall -W"编译安装： root@zhengyang:/work/sambashare/drivers/tslib# make //编译 root@zhengyang:/work/sambashare/drivers/tslib# make install //安装到tmp目录下需要注意的是编译所使用的的版本要和内核编译的版本保持一致，我用的是arm-linux-gcc4.8.3版本。 可以通过如下命令查看可执行文件的平台属性信息： root@zhengyang:/work/sambashare/drivers/tslib# cd tmp root@zhengyang:/work/sambashare/drivers/tslib/tmp# arm-linux-readelf -A bin/ts_test Attribute Section: aeabi File Attributes Tag_CPU_name: "4T" Tag_CPU_arch: v4T Tag_ARM_ISA_use: Yes Tag_THUMB_ISA_use: Thumb-1 Tag_ABI_PCS_wchar_t: 4 Tag_ABI_FP_rounding: Needed Tag_ABI_FP_denormal: Needed Tag_ABI_FP_exceptions: Needed Tag_ABI_FP_number_model: IEEE 754 Tag_ABI_align_needed: 8-byte Tag_ABI_align_preserved: 8-byte, except leaf SP Tag_ABI_enum_size: int 5.3 配置nfs文件系统将tmp里面的bin ，etc，include，lib4个目录下的文件拷贝到文件系统的bin ，etc，include，lib4个目录下 : root@zhengyang:/work/sambashare/drivers/tslib/tmp# cp * /work/nfs_root/rootfs/ -rfd进入nfs文件系统，修改etc/inittab文件： root@zhengyang:/work/sambashare/drivers/tslib/tmp# cd /work/nfs_root/rootfs/ root@zhengyang:/work/sambashare/drivers/tslib/tmp# vim etc/inittab检查是否会启动: tty1: tty1::askfirst:-/bin/sh #在虚拟终端tty1启动askfirst动作的shell，也就是在LCD上会出现Please press Enter to active this console.若有，前面加#，屏蔽掉，这条命令。 5.4 安配置LCD和触摸屏环境 [root@zy:/]# export TSLIB_TSDEVICE=/dev/input/event0 #ts设备文件(触摸屏):event0 [root@zy:/]# export TSLIB_CALIBFILE=/etc/pointercal #校验文件(calibrate file),存放校验值 [root@zy:/]# export TSLIB_CONFFILE=/etc/ts.conf #配置文件 [root@zy:/]# export TSLIB_PLUGINDIR=/lib/ts #插件文件 [root@zy:/]# export TSLIB_CONSOLEDEVICE=none #终端控制台设为NULL [root@zy:/]# export TSLIB_FBDEVICE=/dev/fb0 #fb设备文件(LCD):fb0或者直接写入nfs根文件系统路径下etc/profile文件中。 5.5 测试运行校准程序，触摸屏依次出现5个点，依次点击之： [root@zy:/]# ts_calibrate xres = 240, yres = 320 Took 5 samples... Top left : X = 267 Y = 783 Took 5 samples... Top right : X = 782 Y = 774 Took 3 samples... Bot right : X = 769 Y = 185 Took 2 samples... Bot left : X = 289 Y = 212 Took 19 samples... Center : X = 532 Y = 497 -29.351410 0.281104 0.002008 352.980225 -0.013406 -0.379243 Calibration constants: -1923574 18422 131 23132912 -878 -24854 65536生成的校准文件名为pointercal，位于/etc目录下。 在开发板上执行如下名，就可以在lcd上绘图了： [root@zy:/]# ts_test屏幕最上方会出现三个按钮，分别为“Drag”、“Draw”和“Quit”，默认是第一个，因此，用触摸笔点击任何一处，十字光标便会到那里。
下面是点击Draw按钮并用触摸笔写字的效果图：
同时控制台输出大量信息，其中一小部分： 194.859177: 125 192 255 194.889177: 131 196 255 194.919155: 135 199 255 194.949226: 138 196 255 194.979155: 141 189 255 195.009152: 143 183 255 195.039166: 144 178 255 195.069162: 146 175 255 195.099161: 150 176 255 195.129166: 154 175 255 195.159257: 157 175 255 195.189178: 158 179 255 195.219176: 155 187 255 195.249176: 152 197 255 195.279150: 150 206 255 195.309160: 151 209 255 195.339161: 154 212 255 195.369205: 160 213 0第一列为timeval结构体的两个成员：tv_sec和tv_usec，中间两列分别是X和Y的坐标，最后为pressure，这里可以理解成“触摸事件”，为255表示触摸笔点击了(接触)屏幕，为0表示触摸笔离开了屏幕(这里出现很多的255是正常的，因为写字过程中笔没有离开触摸屏)。点击屏幕上“Quit”或按Ctrl+C可退出该程序。 参考文章 [1]linux驱动移植-LCD驱动基础 [2]linux驱动移植-LCD设备驱动 [3]linux驱动移植-LCD触摸屏设备驱动 [4]基于设备树的TQ2440触摸屏驱动移植 |
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