我的基于input子系统的触摸板驱动,起不来,望赐教

发布于 2022-09-18 19:00:56 字数 23204 浏览 8 评论 0

在linuxdrivers.cn上发表过,转贴到这里问问.

这几天研究触摸板的Linux驱动。看了不少资料，发现主要的代码没有多少，关键倒是和Linux内核交互的东西高不明白。
拿内核源码的驱动改成自己的，硬是起不来，又不知道如何解决。
下面是我的源代码框架，贴在这里，顺便列出自己不明白的地方，请达人指教：

#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/serio.h>
#include <linux/init.h>

#define DRIVER_DESC "Serial touchpad driver"

MODULE_AUTHOR("foobar<foobar@foobar.com>");

MODULE_DESCRIPTION(DRIVER_DESC);

MODULE_LICENSE("GPL");

/**
* Per-touchpad data.
*/
struct sertp {
        struct input_dev *dev; /**< input device */
        struct serio *serio; /**< serio struct */
        s32 id; /**< device id */
        u8 buf[8]; /**< buffer to receive data */
        u8 pre_cnt; /**< received byte pre_cnter */
        s8 phys[32];
};

static irqreturn_t sertp_interrupt(struct serio *serio,
                                   u8 data,
                                   u32 flags,
                                   struct pt_regs *regs)
{
        struct sertp *sertp = serio_get_drvdata(serio);

printk (KERN_ALERT "sertp_interrupt\n");

sertp_process_data(sertp, data, regs); /* start processing data */

return IRQ_HANDLED;
}

static void sertp_disconnect(struct serio *serio)
{
struct sertp *sertp = serio_get_drvdata(serio);

printk (KERN_ALERT "sertp_disconnect\n");

     input_unregister_device(sertp->dev);
     serio_close(serio);
     serio_set_drvdata(serio, NULL);
     kfree(sertp);
}

static int sertp_connect(struct serio *serio, struct serio_driver *drv)
{
     struct sertp *sertp;
     struct input_dev *input_dev;
     int err;
     printk (KERN_ALERT "sertp_connect\n");    /* allocate our struct data and input device */
     sertp = kzalloc(sizeof(struct sertp), GFP_KERNEL);
     input_dev = input_allocate_device();
     if (!sertp || !input_dev) {
         err = -ENOMEM;
         goto fail;
     }

     sertp->serio = serio;
     sertp->id = serio->id.id;
     sertp->dev = input_dev;
     snprintf(sertp->phys, sizeof(sertp->phys), "%s/input0", serio->phys); /* Q0 */
     input_dev->private = sertp;
     input_dev->name = "Serial TouchPad";
     input_dev->phys = sertp->phys; /* Q1 */
     input_dev->id.bustype = BUS_RS232;
     input_dev->id.vendor  = SERIO_ANY; /* Q2 */
     input_dev->id.product = sertp->id;
     input_dev->id.version = 0x0100;
     input_dev->cdev.dev = &serio->dev;
     input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_REL);
     input_dev->keybit[LONG(BTN_MOUSE)] = BIT(BTN_LEFT) | BIT(BTN_RIGHT) | BIT(BTN_MIDDLE);
     input_dev->relbit[0] = BIT(REL_X) | BIT(REL_Y) | BIT(REL_WHEEL) | BIT(REL_HWHEEL);
     serio_set_drvdata(serio, sertp);
     err = serio_open(serio, drv);
     if (err) goto fail;
     input_register_device(sertp->dev);
     return 0;
fail:    serio_set_drvdata(serio, NULL);
     input_free_device(input_dev);
     kfree(sertp);
     return err;
}

static struct serio_device_id sertp_serio_ids[] = {
     {       .type  = SERIO_RS232,
               .proto = SERIO_ANY, /* Q3 */
              .extra = SERIO_ANY,
              .id = SERIO_ANY,
     },
     { 0 }
};

MODULE_DEVICE_TABLE(serio, sertp_serio_ids);

static struct serio_driver sertp_drv = {
     .driver       = {
         .name = "sertp",
     },
     .description = DRIVER_DESC,
     .id_table = sertp_serio_ids,
     .interrupt = sertp_interrupt,
     .connect = sertp_connect,
     .disconnect = sertp_disconnect,
};