LINUX 内核空间中写mtd设备

发布于 2022-09-19 01:30:29 字数 5344 浏览 12 评论 1

内核中读mtd分区中指定长度字节的内容，并存放到字符数组中实现：

      for(i=0;i<MAX_MTD_DEVICES;i++)
      {
            mymtd=get_mtd_device(NULL,i);
            if(mymtd && !strcmp(mymtd->name,"Backup"))
            {
                     printk("Get the MTD %s!n", mymtd->name);
                     break;
            }
      }
      if( i >= MAX_MTD_DEVICES)
      {
            printk("Can't find MTD Conf!n");
            goto err_mtd;
      }

      if (!mymtd | !mymtd->read)
      {
            printk("Can't read MTD!n");
            goto err_mtd;
      }

      buf = kmalloc(MTD_DATA_SIZE, GFP_KERNEL);
      mymtd->read(mymtd, 0, MTD_DATA_SIZE, &retlen, buf);
      if(retlen != MTD_DATA_SIZE){
            printk("Read BAK MTD fails!n");
            kfree(buf);
            goto err_mtd;
      }

但内核中写入将字符数组写入mtd分区的指定位置一直不成功：
            if (!mymtd || !mymtd->erase)
            {
                     printk("Can't erase BAK MTD!n");
                     kfree(buf);
                     goto err_mtd;
            }
            memset(&mymtd_erase_info, 0, sizeof(struct erase_info *));
            mymtd_erase_info.mtd = mymtd;
            mymtd_erase_info.addr = 0;
            mymtd_erase_info.callback = mtd_erase_callback;
            mymtd_erase_info.len = MTD_DATA_SIZE & ~(mymtd->erasesize - 1);
            mymtd->erase(mymtd, &mymtd_erase_info);

            if (!mymtd->write)
            {
                     printk("Can't write BAK MTD!n");
                     kfree(buf);
                     goto err_mtd;
            }
            strncpy(buf + MTD_OPS_OFF, value, length);
            mymtd->write(mymtd, 0, MTD_DATA_SIZE, &retlen, buf);
            if(retlen != MTD_DATA_SIZE){
                     printk("Write BAK MTD fails!n");
                     kfree(buf);
                     goto err_mtd;
            }
上面的erase总是出错，哪位帮忙分析一下，最好有write的过程的code example！谢谢了！