Fixed MTP to work with TWRP

drivers/usb/serial/opticon.c

@@ -0,0 +1,437 @@
+/*
+ * Opticon USB barcode to serial driver
+ *
+ * Copyright (C) 2011 - 2012 Johan Hovold <jhovold@gmail.com>
+ * Copyright (C) 2011 Martin Jansen <martin.jansen@opticon.com>
+ * Copyright (C) 2008 - 2009 Greg Kroah-Hartman <gregkh@suse.de>
+ * Copyright (C) 2008 - 2009 Novell Inc.
+ *
+ *	This program is free software; you can redistribute it and/or
+ *	modify it under the terms of the GNU General Public License version
+ *	2 as published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/tty.h>
+#include <linux/tty_driver.h>
+#include <linux/slab.h>
+#include <linux/tty_flip.h>
+#include <linux/serial.h>
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/usb/serial.h>
+#include <linux/uaccess.h>
+
+#define CONTROL_RTS			0x02
+#define RESEND_CTS_STATE	0x03
+
+/* max number of write urbs in flight */
+#define URB_UPPER_LIMIT	8
+
+/* This driver works for the Opticon 1D barcode reader
+ * an examples of 1D barcode types are EAN, UPC, Code39, IATA etc.. */
+#define DRIVER_DESC	"Opticon USB barcode to serial driver (1D)"
+
+static const struct usb_device_id id_table[] = {
+	{ USB_DEVICE(0x065a, 0x0009) },
+	{ },
+};
+MODULE_DEVICE_TABLE(usb, id_table);
+
+/* This structure holds all of the individual device information */
+struct opticon_private {
+	spinlock_t lock;	/* protects the following flags */
+	bool rts;
+	bool cts;
+	int outstanding_urbs;
+};
+
+
+static void opticon_process_data_packet(struct usb_serial_port *port,
+					const unsigned char *buf, size_t len)
+{
+	tty_insert_flip_string(&port->port, buf, len);
+	tty_flip_buffer_push(&port->port);
+}
+
+static void opticon_process_status_packet(struct usb_serial_port *port,
+					const unsigned char *buf, size_t len)
+{
+	struct opticon_private *priv = usb_get_serial_port_data(port);
+	unsigned long flags;
+
+	spin_lock_irqsave(&priv->lock, flags);
+	if (buf[0] == 0x00)
+		priv->cts = false;
+	else
+		priv->cts = true;
+	spin_unlock_irqrestore(&priv->lock, flags);
+}
+
+static void opticon_process_read_urb(struct urb *urb)
+{
+	struct usb_serial_port *port = urb->context;
+	const unsigned char *hdr = urb->transfer_buffer;
+	const unsigned char *data = hdr + 2;
+	size_t data_len = urb->actual_length - 2;
+
+	if (urb->actual_length <= 2) {
+		dev_dbg(&port->dev, "malformed packet received: %d bytes\n",
+							urb->actual_length);
+		return;
+	}
+	/*
+	 * Data from the device comes with a 2 byte header:
+	 *
+	 * <0x00><0x00>data...
+	 *      This is real data to be sent to the tty layer
+	 * <0x00><0x01>level
+	 *      This is a CTS level change, the third byte is the CTS
+	 *      value (0 for low, 1 for high).
+	 */
+	if ((hdr[0] == 0x00) && (hdr[1] == 0x00)) {
+		opticon_process_data_packet(port, data, data_len);
+	} else if ((hdr[0] == 0x00) && (hdr[1] == 0x01)) {
+		opticon_process_status_packet(port, data, data_len);
+	} else {
+		dev_dbg(&port->dev, "unknown packet received: %02x %02x\n",
+							hdr[0], hdr[1]);
+	}
+}
+
+static int send_control_msg(struct usb_serial_port *port, u8 requesttype,
+				u8 val)
+{
+	struct usb_serial *serial = port->serial;
+	int retval;
+	u8 *buffer;
+
+	buffer = kzalloc(1, GFP_KERNEL);
+	if (!buffer)
+		return -ENOMEM;
+
+	buffer[0] = val;
+	/* Send the message to the vendor control endpoint
+	 * of the connected device */
+	retval = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
+				requesttype,
+				USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_INTERFACE,
+				0, 0, buffer, 1, 0);
+	kfree(buffer);
+
+	if (retval < 0)
+		return retval;
+
+	return 0;
+}
+
+static int opticon_open(struct tty_struct *tty, struct usb_serial_port *port)
+{
+	struct opticon_private *priv = usb_get_serial_port_data(port);
+	unsigned long flags;
+	int res;
+
+	spin_lock_irqsave(&priv->lock, flags);
+	priv->rts = false;
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	/* Clear RTS line */
+	send_control_msg(port, CONTROL_RTS, 0);
+
+	/* clear the halt status of the endpoint */
+	usb_clear_halt(port->serial->dev, port->read_urb->pipe);
+
+	res = usb_serial_generic_open(tty, port);
+	if (!res)
+		return res;
+
+	/* Request CTS line state, sometimes during opening the current
+	 * CTS state can be missed. */
+	send_control_msg(port, RESEND_CTS_STATE, 1);
+
+	return res;
+}
+
+static void opticon_write_control_callback(struct urb *urb)
+{
+	struct usb_serial_port *port = urb->context;
+	struct opticon_private *priv = usb_get_serial_port_data(port);
+	int status = urb->status;
+	unsigned long flags;
+
+	/* free up the transfer buffer, as usb_free_urb() does not do this */
+	kfree(urb->transfer_buffer);
+
+	/* setup packet may be set if we're using it for writing */
+	kfree(urb->setup_packet);
+
+	if (status)
+		dev_dbg(&port->dev,
+			"%s - non-zero urb status received: %d\n",
+			__func__, status);
+
+	spin_lock_irqsave(&priv->lock, flags);
+	--priv->outstanding_urbs;
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	usb_serial_port_softint(port);
+}
+
+static int opticon_write(struct tty_struct *tty, struct usb_serial_port *port,
+			 const unsigned char *buf, int count)
+{
+	struct opticon_private *priv = usb_get_serial_port_data(port);
+	struct usb_serial *serial = port->serial;
+	struct urb *urb;
+	unsigned char *buffer;
+	unsigned long flags;
+	int status;
+	struct usb_ctrlrequest *dr;
+
+	spin_lock_irqsave(&priv->lock, flags);
+	if (priv->outstanding_urbs > URB_UPPER_LIMIT) {
+		spin_unlock_irqrestore(&priv->lock, flags);
+		dev_dbg(&port->dev, "%s - write limit hit\n", __func__);
+		return 0;
+	}
+	priv->outstanding_urbs++;
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	buffer = kmalloc(count, GFP_ATOMIC);
+	if (!buffer) {
+		count = -ENOMEM;
+		goto error_no_buffer;
+	}
+
+	urb = usb_alloc_urb(0, GFP_ATOMIC);
+	if (!urb) {
+		count = -ENOMEM;
+		goto error_no_urb;
+	}
+
+	memcpy(buffer, buf, count);
+
+	usb_serial_debug_data(&port->dev, __func__, count, buffer);
+
+	/* The connected devices do not have a bulk write endpoint,
+	 * to transmit data to de barcode device the control endpoint is used */
+	dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
+	if (!dr) {
+		count = -ENOMEM;
+		goto error_no_dr;
+	}
+
+	dr->bRequestType = USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT;
+	dr->bRequest = 0x01;
+	dr->wValue = 0;
+	dr->wIndex = 0;
+	dr->wLength = cpu_to_le16(count);
+
+	usb_fill_control_urb(urb, serial->dev,
+		usb_sndctrlpipe(serial->dev, 0),
+		(unsigned char *)dr, buffer, count,
+		opticon_write_control_callback, port);
+
+	/* send it down the pipe */
+	status = usb_submit_urb(urb, GFP_ATOMIC);
+	if (status) {
+		dev_err(&port->dev,
+		"%s - usb_submit_urb(write endpoint) failed status = %d\n",
+							__func__, status);
+		count = status;
+		goto error;
+	}
+
+	/* we are done with this urb, so let the host driver
+	 * really free it when it is finished with it */
+	usb_free_urb(urb);
+
+	return count;
+error:
+	kfree(dr);
+error_no_dr:
+	usb_free_urb(urb);
+error_no_urb:
+	kfree(buffer);
+error_no_buffer:
+	spin_lock_irqsave(&priv->lock, flags);
+	--priv->outstanding_urbs;
+	spin_unlock_irqrestore(&priv->lock, flags);
+	return count;
+}
+
+static int opticon_write_room(struct tty_struct *tty)
+{
+	struct usb_serial_port *port = tty->driver_data;
+	struct opticon_private *priv = usb_get_serial_port_data(port);
+	unsigned long flags;
+
+	/*
+	 * We really can take almost anything the user throws at us
+	 * but let's pick a nice big number to tell the tty
+	 * layer that we have lots of free space, unless we don't.
+	 */
+	spin_lock_irqsave(&priv->lock, flags);
+	if (priv->outstanding_urbs > URB_UPPER_LIMIT * 2 / 3) {
+		spin_unlock_irqrestore(&priv->lock, flags);
+		dev_dbg(&port->dev, "%s - write limit hit\n", __func__);
+		return 0;
+	}
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	return 2048;
+}
+
+static int opticon_tiocmget(struct tty_struct *tty)
+{
+	struct usb_serial_port *port = tty->driver_data;
+	struct opticon_private *priv = usb_get_serial_port_data(port);
+	unsigned long flags;
+	int result = 0;
+
+	spin_lock_irqsave(&priv->lock, flags);
+	if (priv->rts)
+		result |= TIOCM_RTS;
+	if (priv->cts)
+		result |= TIOCM_CTS;
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	dev_dbg(&port->dev, "%s - %x\n", __func__, result);
+	return result;
+}
+
+static int opticon_tiocmset(struct tty_struct *tty,
+			   unsigned int set, unsigned int clear)
+{
+	struct usb_serial_port *port = tty->driver_data;
+	struct opticon_private *priv = usb_get_serial_port_data(port);
+	unsigned long flags;
+	bool rts;
+	bool changed = false;
+	int ret;
+
+	/* We only support RTS so we only handle that */
+	spin_lock_irqsave(&priv->lock, flags);
+
+	rts = priv->rts;
+	if (set & TIOCM_RTS)
+		priv->rts = true;
+	if (clear & TIOCM_RTS)
+		priv->rts = false;
+	changed = rts ^ priv->rts;
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	if (!changed)
+		return 0;
+
+	ret = send_control_msg(port, CONTROL_RTS, !rts);
+	if (ret)
+		return usb_translate_errors(ret);
+
+	return 0;
+}
+
+static int get_serial_info(struct usb_serial_port *port,
+			   struct serial_struct __user *serial)
+{
+	struct serial_struct tmp;
+
+	if (!serial)
+		return -EFAULT;
+
+	memset(&tmp, 0x00, sizeof(tmp));
+
+	/* fake emulate a 16550 uart to make userspace code happy */
+	tmp.type		= PORT_16550A;
+	tmp.line		= port->minor;
+	tmp.port		= 0;
+	tmp.irq			= 0;
+	tmp.flags		= ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
+	tmp.xmit_fifo_size	= 1024;
+	tmp.baud_base		= 9600;
+	tmp.close_delay		= 5*HZ;
+	tmp.closing_wait	= 30*HZ;
+
+	if (copy_to_user(serial, &tmp, sizeof(*serial)))
+		return -EFAULT;
+	return 0;
+}
+
+static int opticon_ioctl(struct tty_struct *tty,
+			 unsigned int cmd, unsigned long arg)
+{
+	struct usb_serial_port *port = tty->driver_data;
+
+	switch (cmd) {
+	case TIOCGSERIAL:
+		return get_serial_info(port,
+				       (struct serial_struct __user *)arg);
+	}
+
+	return -ENOIOCTLCMD;
+}
+
+static int opticon_startup(struct usb_serial *serial)
+{
+	if (!serial->num_bulk_in) {
+		dev_err(&serial->dev->dev, "no bulk in endpoint\n");
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int opticon_port_probe(struct usb_serial_port *port)
+{
+	struct opticon_private *priv;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	spin_lock_init(&priv->lock);
+
+	usb_set_serial_port_data(port, priv);
+
+	return 0;
+}
+
+static int opticon_port_remove(struct usb_serial_port *port)
+{
+	struct opticon_private *priv = usb_get_serial_port_data(port);
+
+	kfree(priv);
+
+	return 0;
+}
+
+static struct usb_serial_driver opticon_device = {
+	.driver = {
+		.owner =	THIS_MODULE,
+		.name =		"opticon",
+	},
+	.id_table =		id_table,
+	.num_ports =		1,
+	.bulk_in_size =		256,
+	.attach =		opticon_startup,
+	.port_probe =		opticon_port_probe,
+	.port_remove =		opticon_port_remove,
+	.open =			opticon_open,
+	.write =		opticon_write,
+	.write_room = 		opticon_write_room,
+	.throttle =		usb_serial_generic_throttle,
+	.unthrottle =		usb_serial_generic_unthrottle,
+	.ioctl =		opticon_ioctl,
+	.tiocmget =		opticon_tiocmget,
+	.tiocmset =		opticon_tiocmset,
+	.process_read_urb =	opticon_process_read_urb,
+};
+
+static struct usb_serial_driver * const serial_drivers[] = {
+	&opticon_device, NULL
+};
+
+module_usb_serial_driver(serial_drivers, id_table);
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");