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path: root/drivers/usb/serial/opticon.c
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Diffstat (limited to 'drivers/usb/serial/opticon.c')
-rw-r--r--drivers/usb/serial/opticon.c406
1 files changed, 406 insertions, 0 deletions
diff --git a/drivers/usb/serial/opticon.c b/drivers/usb/serial/opticon.c
new file mode 100644
index 0000000000..e31a6d77da
--- /dev/null
+++ b/drivers/usb/serial/opticon.c
@@ -0,0 +1,406 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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.
+ */
+
+#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;
+ int outstanding_bytes;
+
+ struct usb_anchor anchor;
+};
+
+
+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, USB_CTRL_SET_TIMEOUT);
+ 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_close(struct usb_serial_port *port)
+{
+ struct opticon_private *priv = usb_get_serial_port_data(port);
+
+ usb_kill_anchored_urbs(&priv->anchor);
+
+ usb_serial_generic_close(port);
+}
+
+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;
+ priv->outstanding_bytes -= urb->transfer_buffer_length;
+ 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;
+ struct usb_ctrlrequest *dr;
+ int ret = -ENOMEM;
+
+ 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++;
+ priv->outstanding_bytes += count;
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ buffer = kmemdup(buf, count, GFP_ATOMIC);
+ if (!buffer)
+ goto error_no_buffer;
+
+ urb = usb_alloc_urb(0, GFP_ATOMIC);
+ if (!urb)
+ goto error_no_urb;
+
+ 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)
+ 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);
+
+ usb_anchor_urb(urb, &priv->anchor);
+
+ /* send it down the pipe */
+ ret = usb_submit_urb(urb, GFP_ATOMIC);
+ if (ret) {
+ dev_err(&port->dev, "failed to submit write urb: %d\n", ret);
+ usb_unanchor_urb(urb);
+ 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;
+ priv->outstanding_bytes -= count;
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return ret;
+}
+
+static unsigned 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 unsigned int opticon_chars_in_buffer(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;
+ unsigned int count;
+
+ spin_lock_irqsave(&priv->lock, flags);
+ count = priv->outstanding_bytes;
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return count;
+}
+
+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 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);
+ init_usb_anchor(&priv->anchor);
+
+ usb_set_serial_port_data(port, priv);
+
+ return 0;
+}
+
+static void opticon_port_remove(struct usb_serial_port *port)
+{
+ struct opticon_private *priv = usb_get_serial_port_data(port);
+
+ kfree(priv);
+}
+
+static struct usb_serial_driver opticon_device = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "opticon",
+ },
+ .id_table = id_table,
+ .num_ports = 1,
+ .num_bulk_in = 1,
+ .bulk_in_size = 256,
+ .port_probe = opticon_port_probe,
+ .port_remove = opticon_port_remove,
+ .open = opticon_open,
+ .close = opticon_close,
+ .write = opticon_write,
+ .write_room = opticon_write_room,
+ .chars_in_buffer = opticon_chars_in_buffer,
+ .throttle = usb_serial_generic_throttle,
+ .unthrottle = usb_serial_generic_unthrottle,
+ .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 v2");