mos7840.c

linux 内核源代码

	Data |= SERIAL_LCR_DLAB;	//data latch enable in LCR 0x80
	status = 0;
	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);

	//Data = 0x0c;
	//status = mos7840_set_uart_reg(port,DIVISOR_LATCH_LSB,Data);
	Data = 0x00;
	status = 0;
	status = mos7840_get_uart_reg(port, DIVISOR_LATCH_LSB, &Data);
	dbg("mos7840_write:DLL value is %x\n", Data);

	Data = 0x0;
	status = 0;
	status = mos7840_get_uart_reg(port, DIVISOR_LATCH_MSB, &Data);
	dbg("mos7840_write:DLM value is %x\n", Data);

	Data = Data & ~SERIAL_LCR_DLAB;
	dbg("mos7840_write: mos7840_port->shadowLCR is %x\n",
	    mos7840_port->shadowLCR);
	status = 0;
	status = mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);
#endif

	if (mos7840_port_paranoia_check(port, __FUNCTION__)) {
		dbg("%s", "Port Paranoia failed \n");
		return -1;
	}

	serial = port->serial;
	if (mos7840_serial_paranoia_check(serial, __FUNCTION__)) {
		dbg("%s", "Serial Paranoia failed \n");
		return -1;
	}

	mos7840_port = mos7840_get_port_private(port);
	if (mos7840_port == NULL) {
		dbg("%s", "mos7840_port is NULL\n");
		return -1;
	}

	/* try to find a free urb in the list */
	urb = NULL;

	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
	for (i = 0; i < NUM_URBS; ++i) {
		if (!mos7840_port->busy[i]) {
			mos7840_port->busy[i] = 1;
			urb = mos7840_port->write_urb_pool[i];
			dbg("\nURB:%d", i);
			break;
		}
	}
	spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);

	if (urb == NULL) {
		dbg("%s - no more free urbs", __FUNCTION__);
		goto exit;
	}

	if (urb->transfer_buffer == NULL) {
		urb->transfer_buffer =
		    kmalloc(URB_TRANSFER_BUFFER_SIZE, GFP_KERNEL);

		if (urb->transfer_buffer == NULL) {
			err("%s no more kernel memory...", __FUNCTION__);
			goto exit;
		}
	}
	transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);

	memcpy(urb->transfer_buffer, current_position, transfer_size);

	/* fill urb with data and submit  */
	usb_fill_bulk_urb(urb,
			  serial->dev,
			  usb_sndbulkpipe(serial->dev,
					  port->bulk_out_endpointAddress),
			  urb->transfer_buffer,
			  transfer_size,
			  mos7840_bulk_out_data_callback, mos7840_port);

	data1 = urb->transfer_buffer;
	dbg("\nbulkout endpoint is %d", port->bulk_out_endpointAddress);

	/* send it down the pipe */
	status = usb_submit_urb(urb, GFP_ATOMIC);

	if (status) {
		mos7840_port->busy[i] = 0;
		err("%s - usb_submit_urb(write bulk) failed with status = %d",
		    __FUNCTION__, status);
		bytes_sent = status;
		goto exit;
	}
	bytes_sent = transfer_size;
	mos7840_port->icount.tx += transfer_size;
	smp_wmb();
	dbg("mos7840_port->icount.tx is %d:\n", mos7840_port->icount.tx);
      exit:

	return bytes_sent;

}

/*****************************************************************************
 * mos7840_throttle
 *	this function is called by the tty driver when it wants to stop the data
 *	being read from the port.
 *****************************************************************************/

static void mos7840_throttle(struct usb_serial_port *port)
{
	struct moschip_port *mos7840_port;
	struct tty_struct *tty;
	int status;

	if (mos7840_port_paranoia_check(port, __FUNCTION__)) {
		dbg("%s", "Invalid port \n");
		return;
	}

	dbg("- port %d\n", port->number);

	mos7840_port = mos7840_get_port_private(port);

	if (mos7840_port == NULL)
		return;

	if (!mos7840_port->open) {
		dbg("%s\n", "port not opened");
		return;
	}

	dbg("%s", "Entering .......... \n");

	tty = port->tty;
	if (!tty) {
		dbg("%s - no tty available", __FUNCTION__);
		return;
	}

	/* if we are implementing XON/XOFF, send the stop character */
	if (I_IXOFF(tty)) {
		unsigned char stop_char = STOP_CHAR(tty);
		status = mos7840_write(port, &stop_char, 1);
		if (status <= 0) {
			return;
		}
	}

	/* if we are implementing RTS/CTS, toggle that line */
	if (tty->termios->c_cflag & CRTSCTS) {
		mos7840_port->shadowMCR &= ~MCR_RTS;
		status = 0;
		status =
		    mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
					 mos7840_port->shadowMCR);

		if (status < 0) {
			return;
		}
	}

	return;
}

/*****************************************************************************
 * mos7840_unthrottle
 *	this function is called by the tty driver when it wants to resume the data
 *	being read from the port (called after SerialThrottle is called)
 *****************************************************************************/
static void mos7840_unthrottle(struct usb_serial_port *port)
{
	struct tty_struct *tty;
	int status;
	struct moschip_port *mos7840_port = mos7840_get_port_private(port);

	if (mos7840_port_paranoia_check(port, __FUNCTION__)) {
		dbg("%s", "Invalid port \n");
		return;
	}

	if (mos7840_port == NULL)
		return;

	if (!mos7840_port->open) {
		dbg("%s - port not opened", __FUNCTION__);
		return;
	}

	dbg("%s", "Entering .......... \n");

	tty = port->tty;
	if (!tty) {
		dbg("%s - no tty available", __FUNCTION__);
		return;
	}

	/* if we are implementing XON/XOFF, send the start character */
	if (I_IXOFF(tty)) {
		unsigned char start_char = START_CHAR(tty);
		status = mos7840_write(port, &start_char, 1);
		if (status <= 0) {
			return;
		}
	}

	/* if we are implementing RTS/CTS, toggle that line */
	if (tty->termios->c_cflag & CRTSCTS) {
		mos7840_port->shadowMCR |= MCR_RTS;
		status = 0;
		status =
		    mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER,
					 mos7840_port->shadowMCR);
		if (status < 0) {
			return;
		}
	}

	return;
}

static int mos7840_tiocmget(struct usb_serial_port *port, struct file *file)
{
	struct moschip_port *mos7840_port;
	unsigned int result;
	__u16 msr;
	__u16 mcr;
	int status = 0;
	mos7840_port = mos7840_get_port_private(port);

	dbg("%s - port %d", __FUNCTION__, port->number);

	if (mos7840_port == NULL)
		return -ENODEV;

	status = mos7840_get_uart_reg(port, MODEM_STATUS_REGISTER, &msr);
	status = mos7840_get_uart_reg(port, MODEM_CONTROL_REGISTER, &mcr);
	result = ((mcr & MCR_DTR) ? TIOCM_DTR : 0)
	    | ((mcr & MCR_RTS) ? TIOCM_RTS : 0)
	    | ((mcr & MCR_LOOPBACK) ? TIOCM_LOOP : 0)
	    | ((msr & MOS7840_MSR_CTS) ? TIOCM_CTS : 0)
	    | ((msr & MOS7840_MSR_CD) ? TIOCM_CAR : 0)
	    | ((msr & MOS7840_MSR_RI) ? TIOCM_RI : 0)
	    | ((msr & MOS7840_MSR_DSR) ? TIOCM_DSR : 0);

	dbg("%s - 0x%04X", __FUNCTION__, result);

	return result;
}

static int mos7840_tiocmset(struct usb_serial_port *port, struct file *file,
			    unsigned int set, unsigned int clear)
{
	struct moschip_port *mos7840_port;
	unsigned int mcr;
	unsigned int status;

	dbg("%s - port %d", __FUNCTION__, port->number);

	mos7840_port = mos7840_get_port_private(port);

	if (mos7840_port == NULL)
		return -ENODEV;

	mcr = mos7840_port->shadowMCR;
	if (clear & TIOCM_RTS)
		mcr &= ~MCR_RTS;
	if (clear & TIOCM_DTR)
		mcr &= ~MCR_DTR;
	if (clear & TIOCM_LOOP)
		mcr &= ~MCR_LOOPBACK;

	if (set & TIOCM_RTS)
		mcr |= MCR_RTS;
	if (set & TIOCM_DTR)
		mcr |= MCR_DTR;
	if (set & TIOCM_LOOP)
		mcr |= MCR_LOOPBACK;

	mos7840_port->shadowMCR = mcr;

	status = 0;
	status = mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, mcr);
	if (status < 0) {
		dbg("setting MODEM_CONTROL_REGISTER Failed\n");
		return -1;
	}

	return 0;
}

/*****************************************************************************
 * mos7840_calc_baud_rate_divisor
 *	this function calculates the proper baud rate divisor for the specified
 *	baud rate.
 *****************************************************************************/
static int mos7840_calc_baud_rate_divisor(int baudRate, int *divisor,
					  __u16 * clk_sel_val)
{

	dbg("%s - %d", __FUNCTION__, baudRate);

	if (baudRate <= 115200) {
		*divisor = 115200 / baudRate;
		*clk_sel_val = 0x0;
	}
	if ((baudRate > 115200) && (baudRate <= 230400)) {
		*divisor = 230400 / baudRate;
		*clk_sel_val = 0x10;
	} else if ((baudRate > 230400) && (baudRate <= 403200)) {
		*divisor = 403200 / baudRate;
		*clk_sel_val = 0x20;
	} else if ((baudRate > 403200) && (baudRate <= 460800)) {
		*divisor = 460800 / baudRate;
		*clk_sel_val = 0x30;
	} else if ((baudRate > 460800) && (baudRate <= 806400)) {
		*divisor = 806400 / baudRate;
		*clk_sel_val = 0x40;
	} else if ((baudRate > 806400) && (baudRate <= 921600)) {
		*divisor = 921600 / baudRate;
		*clk_sel_val = 0x50;
	} else if ((baudRate > 921600) && (baudRate <= 1572864)) {
		*divisor = 1572864 / baudRate;
		*clk_sel_val = 0x60;
	} else if ((baudRate > 1572864) && (baudRate <= 3145728)) {
		*divisor = 3145728 / baudRate;
		*clk_sel_val = 0x70;
	}
	return 0;

#ifdef NOTMCS7840

	for (i = 0; i < ARRAY_SIZE(mos7840_divisor_table); i++) {
		if (mos7840_divisor_table[i].BaudRate == baudrate) {
			*divisor = mos7840_divisor_table[i].Divisor;
			return 0;
		}
	}

	/* After trying for all the standard baud rates    *
	 * Try calculating the divisor for this baud rate  */

	if (baudrate > 75 && baudrate < 230400) {
		/* get the divisor */
		custom = (__u16) (230400L / baudrate);

		/* Check for round off */
		round1 = (__u16) (2304000L / baudrate);
		round = (__u16) (round1 - (custom * 10));
		if (round > 4) {
			custom++;
		}
		*divisor = custom;

		dbg(" Baud %d = %d\n", baudrate, custom);
		return 0;
	}

	dbg("%s\n", " Baud calculation Failed...");
	return -1;
#endif
}

/*****************************************************************************
 * mos7840_send_cmd_write_baud_rate
 *	this function sends the proper command to change the baud rate of the
 *	specified port.
 *****************************************************************************/

static int mos7840_send_cmd_write_baud_rate(struct moschip_port *mos7840_port,
					    int baudRate)
{
	int divisor = 0;
	int status;
	__u16 Data;
	unsigned char number;
	__u16 clk_sel_val;
	struct usb_serial_port *port;

	if (mos7840_port == NULL)
		return -1;

	port = (struct usb_serial_port *)mos7840_port->port;
	if (mos7840_port_paranoia_check(port, __FUNCTION__)) {
		dbg("%s", "Invalid port \n");
		return -1;
	}

	if (mos7840_serial_paranoia_check(port->serial, __FUNCTION__)) {
		dbg("%s", "Invalid Serial \n");
		return -1;
	}

	dbg("%s", "Entering .......... \n");

	number = mos7840_port->port->number - mos7840_port->port->serial->minor;

	dbg("%s - port = %d, baud = %d", __FUNCTION__,
	    mos7840_port->port->number, baudRate);
	//reset clk_uart_sel in spregOffset
	if (baudRate > 115200) {
#ifdef HW_flow_control
		//NOTE: need to see the pther register to modify
		//setting h/w flow control bit to 1;
		status = 0;
		Data = 0x2b;
		mos7840_port->shadowMCR = Data;
		status =
		    mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
		if (status < 0) {
			dbg("Writing spreg failed in set_serial_baud\n");
			return -1;
		}
#endif

	} else {
#ifdef HW_flow_control
		//setting h/w flow control bit to 0;
		status = 0;
		Data = 0xb;
		mos7840_port->shadowMCR = Data;
		status =
		    mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
		if (status < 0) {
			dbg("Writing spreg failed in set_serial_baud\n");
			return -1;
		}
#endif

	}

	if (1)			//baudRate <= 115200)
	{
		clk_sel_val = 0x0;
		Data = 0x0;
		status = 0;
		status =
		    mos7840_calc_baud_rate_divisor(baudRate, &divisor,
						   &clk_sel_val);
		status =
		    mos7840_get_reg_sync(port, mos7840_port->SpRegOffset,
					 &Data);
		if (status < 0) {
			dbg("reading spreg failed in set_serial_baud\n");
			return -1;
		}
		Data = (Data & 0x8f) | clk_sel_val;
		status = 0;
		status =
		    mos7840_set_reg_sync(port, mos7840_port->SpRegOffset, Data);
		if (status < 0) {
			dbg("Writing spreg failed in set_serial_baud\n");
			return -1;
		}
		/* Calculate the Divisor */

		if (status) {
			err("%s - bad baud rate", __FUNCTION__);
			dbg("%s\n", "bad baud rate");
			return status;
		}
		/* Enable access to divisor latch */
		Data = mos7840_port->shadowLCR | SERIAL_LCR_DLAB;
		mos7840_port->shadowLCR = Data;
		mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);

		/* Write the divisor */
		Data = (unsigned char)(divisor & 0xff);
		dbg("set_serial_baud Value to write DLL is %x\n", Data);
		mos7840_set_uart_reg(port, DIVISOR_LATCH_LSB, Data);

		Data = (unsigned char)((divisor & 0xff00) >> 8);
		dbg("set_serial_baud Value to write DLM is %x\n", Data);
		mos7840_set_uart_reg(port, DIVISOR_LATCH_MSB, Data);

		/* Disable access to divisor latch */
		Data = mos7840_port->shadowLCR & ~SERIAL_LCR_DLAB;
		mos7840_port->shadowLCR = Data;
		mos7840_set_uart_reg(port, LINE_CONTROL_REGISTER, Data);

	}