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标题: NUC980 串口设置1200及以下波特率时无法设置成功 [打印本页]

作者: 匿名 时间: 2024-12-6 18:13
标题: NUC980 串口设置1200及以下波特率时无法设置成功

内核版本：
使用的就是github上最新的内核

在内核驱动代码nuc980_serial.c文件里的nuc980serial_set_termios函数里加入一条打印信息:

static void
nuc980serial_set_termios(struct uart_port *port, struct ktermios *termios, struct ktermios *old)
{
struct uart_nuc980_port *up = (struct uart_nuc980_port *)port;
unsigned int lcr = 0;
unsigned long flags;
unsigned int baud, quot;

switch (termios->c_cflag & CSIZE) {
case CS5:
      lcr = 0;
      break;
case CS6:
      lcr |= 1;
      break;
case CS7:
      lcr |= 2;
      break;
default:
case CS8:
      lcr |= 3;
      break;
}

if (termios->c_cflag & CSTOPB)
      lcr |= NSB;
if (termios->c_cflag & PARENB)
      lcr |= PBE;
if (!(termios->c_cflag & PARODD))
      lcr |= EPE;
if (termios->c_cflag & CMSPAR)
      lcr |= SPE;

baud = uart_get_baud_rate(port, termios, old, port->uartclk / 0xffff, port->uartclk / 11);
quot = nuc980serial_get_divisor(port, baud);
printk("in nuc980serial_set_termios, quot = %d, baud = %d \n", quot, baud); //增加这一条打印信息
/*
   * Ok, we're now changing the port state.  Do it with
   * interrupts disabled.
   */
spin_lock_irqsave(&up->port.lock, flags);

up->port.read_status_mask = RX_OVER_IF /*| UART_LSR_THRE | UART_LSR_DR*/;
if (termios->c_iflag & INPCK)
      up->port.read_status_mask |= FEF | PEF;
if (termios->c_iflag & (BRKINT | PARMRK))
      up->port.read_status_mask |= BIF;

/*
   * Characteres to ignore
   */
up->port.ignore_status_mask = 0;
if (termios->c_iflag & IGNPAR)
      up->port.ignore_status_mask |= FEF | PEF;
if (termios->c_iflag & IGNBRK) {
      up->port.ignore_status_mask |= BIF;
      /*
      * If we're ignoring parity and break indicators,
      * ignore overruns too (for real raw support).
      */
      if (termios->c_iflag & IGNPAR)
         up->port.ignore_status_mask |= RX_OVER_IF;
}

if (termios->c_cflag & CRTSCTS)
      up->mcr |= UART_MCR_AFE;
else
      up->mcr &= ~UART_MCR_AFE;

nuc980serial_set_mctrl(&up->port, up->port.mctrl);

serial_out(up, UART_REG_BAUD, quot | 0x30000000);

serial_out(up, UART_REG_LCR, lcr);

spin_unlock_irqrestore(&up->port.lock, flags);

}

然后重新编译内核，下载重启后，通过应用程序设置波特率，设置1200波特率及以下波特率时，

这个打印的波特率就一直是9600

请问这个问题应该如何解决？

谢谢！

作者: 匿名 时间: 2024-12-10 15:36
检查下uartclk 是否设置成功

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