rk3288 android12 串口数据分段接收

kernel-4.19/drivers/tty/serial/8250/8250_early.c
diff --git a/kernel-4.19/drivers/tty/serial/8250/8250_port.c b/kernel-4.19/drivers/tty/serial/8250/8250_port.c
old mode 100644
new mode 100755
index 39156ecbeb…4557b63e48
— a/kernel-4.19/drivers/tty/serial/8250/8250_port.c
+++ b/kernel-4.19/drivers/tty/serial/8250/8250_port.c
@@ -1768,17 +1768,31 @@ EXPORT_SYMBOL_GPL(serial8250_read_char);
*/
unsigned char serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr)
{
+printk(KERN_INFO " serial8250_rx_chars ");
struct uart_port *port = &up->port;
int max_count = 256;

•   unsigned int iir = serial_port_in(port, UART_IIR);
  

•   if ((iir & 0x0f) == 0x0c){
  

•           max_count = serial_in(up, UART_RFL);
  

•   }
  

•   else{
  

•           max_count = serial_in(up, UART_RFL) - 2;
  

•   }
  

•   max_count = 256;
  

•   printk(KERN_INFO " max_count %d ",max_count);
    do {
            serial8250_read_char(up, lsr);
            if (--max_count == 0)
                    break;
            lsr = serial_in(up, UART_LSR);
  

•   } while (lsr & (UART_LSR_DR | UART_LSR_BI));
  

•   } while (lsr & (UART_LSR_DR | UART_LSR_BI) && (max_count-- > 0));
  

•   if ((iir & 0x0f) == 0x0c){
    tty_flip_buffer_push(&port->state->port);
  

•   printk(KERN_INFO " tty_flip_buffer_push ");
  

•   }
    return lsr;
  

}