USB: spcp8x5: reimplement using generic framework (fa993ca8) · Commits · 方亚芬 / linux

drivers/usb/serial/spcp8x5.c

+29 −378

Original line number	Diff line number	Diff line
		/*
		* spcp8x5 USB to serial adaptor driver
		*
		* Copyright (C) 2010 Johan Hovold (jhovold@gmail.com)
		* Copyright (C) 2006 Linxb (xubin.lin@worldplus.com.cn)
		* Copyright (C) 2006 S1 Corp.
		*
		@@ -29,7 +30,7 @@


		/* Version Information */
		#define DRIVER_VERSION "v0.04"
		#define DRIVER_VERSION "v0.10"
		#define DRIVER_DESC "SPCP8x5 USB to serial adaptor driver"

		static int debug;
		@@ -64,11 +65,6 @@ struct spcp8x5_usb_ctrl_arg {
		u16 length;
		};

		/* wait 30s before close */
		#define SPCP8x5_CLOSING_WAIT (30*HZ)

		#define SPCP8x5_BUF_SIZE 1024


		/* spcp8x5 spec register define */
		#define MCR_CONTROL_LINE_RTS 0x02
		@@ -155,133 +151,6 @@ enum spcp8x5_type {
		SPCP835_TYPE,
		};

		/* 1st in 1st out buffer 4 driver */
		struct ringbuf {
		unsigned int buf_size;
		char *buf_buf;
		char *buf_get;
		char *buf_put;
		};

		/* alloc the ring buf and alloc the buffer itself */
		static inline struct ringbuf *alloc_ringbuf(unsigned int size)
		{
		struct ringbuf *pb;

		if (size == 0)
		return NULL;

		pb = kmalloc(sizeof(*pb), GFP_KERNEL);
		if (pb == NULL)
		return NULL;

		pb->buf_buf = kmalloc(size, GFP_KERNEL);
		if (pb->buf_buf == NULL) {
		kfree(pb);
		return NULL;
		}

		pb->buf_size = size;
		pb->buf_get = pb->buf_put = pb->buf_buf;

		return pb;
		}

		/* free the ring buf and the buffer itself */
		static inline void free_ringbuf(struct ringbuf *pb)
		{
		if (pb != NULL) {
		kfree(pb->buf_buf);
		kfree(pb);
		}
		}

		/* clear pipo , juest repoint the pointer here */
		static inline void clear_ringbuf(struct ringbuf *pb)
		{
		if (pb != NULL)
		pb->buf_get = pb->buf_put;
		}

		/* get the number of data in the pipo */
		static inline unsigned int ringbuf_avail_data(struct ringbuf *pb)
		{
		if (pb == NULL)
		return 0;
		return (pb->buf_size + pb->buf_put - pb->buf_get) % pb->buf_size;
		}

		/* get the number of space in the pipo */
		static inline unsigned int ringbuf_avail_space(struct ringbuf *pb)
		{
		if (pb == NULL)
		return 0;
		return (pb->buf_size + pb->buf_get - pb->buf_put - 1) % pb->buf_size;
		}

		/* put count data into pipo */
		static unsigned int put_ringbuf(struct ringbuf pb, const char buf,
		unsigned int count)
		{
		unsigned int len;

		if (pb == NULL)
		return 0;

		len = ringbuf_avail_space(pb);
		if (count > len)
		count = len;

		if (count == 0)
		return 0;

		len = pb->buf_buf + pb->buf_size - pb->buf_put;
		if (count > len) {
		memcpy(pb->buf_put, buf, len);
		memcpy(pb->buf_buf, buf+len, count - len);
		pb->buf_put = pb->buf_buf + count - len;
		} else {
		memcpy(pb->buf_put, buf, count);
		if (count < len)
		pb->buf_put += count;
		else /* count == len */
		pb->buf_put = pb->buf_buf;
		}
		return count;
		}

		/* get count data from pipo */
		static unsigned int get_ringbuf(struct ringbuf pb, char buf,
		unsigned int count)
		{
		unsigned int len;

		if (pb == NULL \|\| buf == NULL)
		return 0;

		len = ringbuf_avail_data(pb);
		if (count > len)
		count = len;

		if (count == 0)
		return 0;

		len = pb->buf_buf + pb->buf_size - pb->buf_get;
		if (count > len) {
		memcpy(buf, pb->buf_get, len);
		memcpy(buf+len, pb->buf_buf, count - len);
		pb->buf_get = pb->buf_buf + count - len;
		} else {
		memcpy(buf, pb->buf_get, count);
		if (count < len)
		pb->buf_get += count;
		else /* count == len */
		pb->buf_get = pb->buf_buf;
		}

		return count;
		}

		static struct usb_driver spcp8x5_driver = {
		.name = "spcp8x5",
		.probe = usb_serial_probe,
		@@ -293,8 +162,6 @@ static struct usb_driver spcp8x5_driver = {

		struct spcp8x5_private {
		spinlock_t lock;
		struct ringbuf *buf;
		int write_urb_in_use;
		enum spcp8x5_type type;
		wait_queue_head_t delta_msr_wait;
		u8 line_control;
		@@ -330,24 +197,15 @@ static int spcp8x5_startup(struct usb_serial *serial)
		goto cleanup;

		spin_lock_init(&priv->lock);
		priv->buf = alloc_ringbuf(SPCP8x5_BUF_SIZE);
		if (priv->buf == NULL)
		goto cleanup2;

		init_waitqueue_head(&priv->delta_msr_wait);
		priv->type = type;
		usb_set_serial_port_data(serial->port[i] , priv);

		}

		return 0;

		cleanup2:
		kfree(priv);
		cleanup:
		for (--i; i >= 0; --i) {
		priv = usb_get_serial_port_data(serial->port[i]);
		free_ringbuf(priv->buf);
		kfree(priv);
		usb_set_serial_port_data(serial->port[i] , NULL);
		}
		@@ -358,15 +216,9 @@ static int spcp8x5_startup(struct usb_serial *serial)
		static void spcp8x5_release(struct usb_serial *serial)
		{
		int i;
		struct spcp8x5_private *priv;

		for (i = 0; i < serial->num_ports; i++) {
		priv = usb_get_serial_port_data(serial->port[i]);
		if (priv) {
		free_ringbuf(priv->buf);
		kfree(priv);
		}
		}
		for (i = 0; i < serial->num_ports; i++)
		kfree(usb_get_serial_port_data(serial->port[i]));
		}

		/* set the modem control line of the device.
		@@ -470,33 +322,6 @@ static void spcp8x5_dtr_rts(struct usb_serial_port *port, int on)
		spcp8x5_set_ctrlLine(port->serial->dev, control , priv->type);
		}

		/* close the serial port. We should wait for data sending to device 1st and
		* then kill all urb. */
		static void spcp8x5_close(struct usb_serial_port *port)
		{
		struct spcp8x5_private *priv = usb_get_serial_port_data(port);
		unsigned long flags;
		int result;

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

		spin_lock_irqsave(&priv->lock, flags);
		/* clear out any remaining data in the buffer */
		clear_ringbuf(priv->buf);
		spin_unlock_irqrestore(&priv->lock, flags);

		/* kill urb */
		if (port->write_urb != NULL) {
		result = usb_unlink_urb(port->write_urb);
		if (result)
		dev_dbg(&port->dev,
		"usb_unlink_urb(write_urb) = %d\n", result);
		}
		result = usb_unlink_urb(port->read_urb);
		if (result)
		dev_dbg(&port->dev, "usb_unlink_urb(read_urb) = %d\n", result);
		}

		static void spcp8x5_init_termios(struct tty_struct *tty)
		{
		/* for the 1st time call this function */
		@@ -620,7 +445,7 @@ static void spcp8x5_set_termios(struct tty_struct *tty,
		}

		/* open the serial port. do some usb system call. set termios and get the line
		* status of the device. then submit the read urb */
		* status of the device. */
		static int spcp8x5_open(struct tty_struct tty, struct usb_serial_port port)
		{
		struct ktermios tmp_termios;
		@@ -655,52 +480,21 @@ static int spcp8x5_open(struct tty_struct tty, struct usb_serial_port port)
		priv->line_status = status & 0xf0 ;
		spin_unlock_irqrestore(&priv->lock, flags);

		dbg("%s - submitting read urb", __func__);
		port->read_urb->dev = serial->dev;
		ret = usb_submit_urb(port->read_urb, GFP_KERNEL);
		if (ret) {
		spcp8x5_close(port);
		return -EPROTO;
		}
		port->port.drain_delay = 256;
		return 0;

		return usb_serial_generic_open(tty, port);
		}

		/* bulk read call back function. check the status of the urb. if transfer
		* failed return. then update the status and the tty send data to tty subsys.
		* submit urb again.
		*/
		static void spcp8x5_read_bulk_callback(struct urb *urb)
		static void spcp8x5_process_read_urb(struct urb *urb)
		{
		struct usb_serial_port *port = urb->context;
		struct spcp8x5_private *priv = usb_get_serial_port_data(port);
		struct tty_struct *tty;
		unsigned char *data = urb->transfer_buffer;
		unsigned long flags;
		int result = urb->status;
		u8 status;
		char tty_flag;

		dev_dbg(&port->dev, "start, result = %d, urb->actual_length = %d\n,",
		result, urb->actual_length);

		/* check the urb status */
		if (result) {
		if (result == -EPROTO) {
		/* spcp8x5 mysteriously fails with -EPROTO */
		/* reschedule the read */
		urb->dev = port->serial->dev;
		result = usb_submit_urb(urb , GFP_ATOMIC);
		if (result)
		dev_dbg(&port->dev,
		"failed submitting read urb %d\n",
		result);
		return;
		}
		dev_dbg(&port->dev, "unable to handle the error, exiting.\n");
		return;
		}

		/* get tty_flag from status */
		tty_flag = TTY_NORMAL;

		@@ -711,8 +505,16 @@ static void spcp8x5_read_bulk_callback(struct urb *urb)
		/* wake up the wait for termios */
		wake_up_interruptible(&priv->delta_msr_wait);

		/* break takes precedence over parity, which takes precedence over
		* framing errors */
		if (!urb->actual_length)
		return;

		tty = tty_port_tty_get(&port->port);
		if (!tty)
		return;

		if (status & UART_STATE_TRANSIENT_MASK) {
		/* break takes precedence over parity, which takes precedence
		* over framing errors */
		if (status & UART_BREAK_ERROR)
		tty_flag = TTY_BREAK;
		else if (status & UART_PARITY_ERROR)
		@@ -721,131 +523,15 @@ static void spcp8x5_read_bulk_callback(struct urb *urb)
		tty_flag = TTY_FRAME;
		dev_dbg(&port->dev, "tty_flag = %d\n", tty_flag);

		tty = tty_port_tty_get(&port->port);
		if (tty && urb->actual_length) {
		/* overrun is special, not associated with a char */
		if (status & UART_OVERRUN_ERROR)
		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
		}

		tty_insert_flip_string_fixed_flag(tty, data, tty_flag,
		urb->actual_length);
		tty_flip_buffer_push(tty);
		}
		tty_kref_put(tty);

		/* Schedule the next read */
		urb->dev = port->serial->dev;
		result = usb_submit_urb(urb , GFP_ATOMIC);
		if (result)
		dev_dbg(&port->dev, "failed submitting read urb %d\n", result);
		}

		/* get data from ring buffer and then write to usb bus */
		static void spcp8x5_send(struct usb_serial_port *port)
		{
		int count, result;
		struct spcp8x5_private *priv = usb_get_serial_port_data(port);
		unsigned long flags;

		spin_lock_irqsave(&priv->lock, flags);

		if (priv->write_urb_in_use) {
		dev_dbg(&port->dev, "write urb still used\n");
		spin_unlock_irqrestore(&priv->lock, flags);
		return;
		}

		/* send the 1st urb for writting */
		memset(port->write_urb->transfer_buffer , 0x00 , port->bulk_out_size);
		count = get_ringbuf(priv->buf, port->write_urb->transfer_buffer,
		port->bulk_out_size);

		if (count == 0) {
		spin_unlock_irqrestore(&priv->lock, flags);
		return;
		}

		/* update the urb status */
		priv->write_urb_in_use = 1;

		spin_unlock_irqrestore(&priv->lock, flags);

		port->write_urb->transfer_buffer_length = count;
		port->write_urb->dev = port->serial->dev;

		result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
		if (result) {
		dev_dbg(&port->dev, "failed submitting write urb, error %d\n",
		result);
		priv->write_urb_in_use = 0;
		/* TODO: reschedule spcp8x5_send */
		}


		schedule_work(&port->work);
		}

		/* this is the call back function for write urb. NOTE we should not sleep in
		* this routine. check the urb return code and then submit the write urb again
		* to hold the write loop */
		static void spcp8x5_write_bulk_callback(struct urb *urb)
		{
		struct usb_serial_port *port = urb->context;
		struct spcp8x5_private *priv = usb_get_serial_port_data(port);
		int result;
		int status = urb->status;

		switch (status) {
		case 0:
		/* success */
		break;
		case -ECONNRESET:
		case -ENOENT:
		case -ESHUTDOWN:
		/* this urb is terminated, clean up */
		dev_dbg(&port->dev, "urb shutting down with status: %d\n",
		status);
		priv->write_urb_in_use = 0;
		return;
		default:
		/* error in the urb, so we have to resubmit it */
		dbg("%s - Overflow in write", __func__);
		dbg("%s - nonzero write bulk status received: %d",
		__func__, status);
		port->write_urb->transfer_buffer_length = 1;
		port->write_urb->dev = port->serial->dev;
		result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
		if (result)
		dev_dbg(&port->dev,
		"failed resubmitting write urb %d\n", result);
		else
		return;
		}

		priv->write_urb_in_use = 0;

		/* send any buffered data */
		spcp8x5_send(port);
		}

		/* write data to ring buffer. and then start the write transfer */
		static int spcp8x5_write(struct tty_struct tty, struct usb_serial_port port,
		const unsigned char *buf, int count)
		{
		struct spcp8x5_private *priv = usb_get_serial_port_data(port);
		unsigned long flags;

		dev_dbg(&port->dev, "%d bytes\n", count);

		if (!count)
		return count;

		spin_lock_irqsave(&priv->lock, flags);
		count = put_ringbuf(priv->buf, buf, count);
		spin_unlock_irqrestore(&priv->lock, flags);

		spcp8x5_send(port);

		return count;
		}

		static int spcp8x5_wait_modem_info(struct usb_serial_port *port,
		@@ -953,36 +639,6 @@ static int spcp8x5_tiocmget(struct tty_struct tty, struct file file)
		return result;
		}

		/* get the avail space room in ring buffer */
		static int spcp8x5_write_room(struct tty_struct *tty)
		{
		struct usb_serial_port *port = tty->driver_data;
		struct spcp8x5_private *priv = usb_get_serial_port_data(port);
		int room = 0;
		unsigned long flags;

		spin_lock_irqsave(&priv->lock, flags);
		room = ringbuf_avail_space(priv->buf);
		spin_unlock_irqrestore(&priv->lock, flags);

		return room;
		}

		/* get the number of avail data in write ring buffer */
		static int spcp8x5_chars_in_buffer(struct tty_struct *tty)
		{
		struct usb_serial_port *port = tty->driver_data;
		struct spcp8x5_private *priv = usb_get_serial_port_data(port);
		int chars = 0;
		unsigned long flags;

		spin_lock_irqsave(&priv->lock, flags);
		chars = ringbuf_avail_data(priv->buf);
		spin_unlock_irqrestore(&priv->lock, flags);

		return chars;
		}

		/* All of the device info needed for the spcp8x5 SIO serial converter */
		static struct usb_serial_driver spcp8x5_device = {
		.driver = {
		@@ -992,21 +648,16 @@ static struct usb_serial_driver spcp8x5_device = {
		.id_table = id_table,
		.num_ports = 1,
		.open = spcp8x5_open,
		.close = spcp8x5_close,
		.dtr_rts = spcp8x5_dtr_rts,
		.carrier_raised = spcp8x5_carrier_raised,
		.write = spcp8x5_write,
		.set_termios = spcp8x5_set_termios,
		.init_termios = spcp8x5_init_termios,
		.ioctl = spcp8x5_ioctl,
		.tiocmget = spcp8x5_tiocmget,
		.tiocmset = spcp8x5_tiocmset,
		.write_room = spcp8x5_write_room,
		.read_bulk_callback = spcp8x5_read_bulk_callback,
		.write_bulk_callback = spcp8x5_write_bulk_callback,
		.chars_in_buffer = spcp8x5_chars_in_buffer,
		.attach = spcp8x5_startup,
		.release = spcp8x5_release,
		.process_read_urb = spcp8x5_process_read_urb,
		};

		static int __init spcp8x5_init(void)