usb/serial/metro-usb.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003   Some of this code is credited to Linux USB open source files that are
0004   distributed with Linux.
0005
0006   Copyright:    2007 Metrologic Instruments. All rights reserved.
0007   Copyright:    2011 Azimut Ltd. <http://azimutrzn.ru/>
0008 */
0009
0010 #include <linux/kernel.h>
0011 #include <linux/tty.h>
0012 #include <linux/module.h>
0013 #include <linux/usb.h>
0014 #include <linux/errno.h>
0015 #include <linux/slab.h>
0016 #include <linux/tty_driver.h>
0017 #include <linux/tty_flip.h>
0018 #include <linux/moduleparam.h>
0019 #include <linux/spinlock.h>
0020 #include <linux/uaccess.h>
0021 #include <linux/usb/serial.h>
0022
0023 #define DRIVER_DESC "Metrologic Instruments Inc. - USB-POS driver"
0024
0025 /* Product information. */
0026 #define FOCUS_VENDOR_ID         0x0C2E
0027 #define FOCUS_PRODUCT_ID_BI     0x0720
0028 #define FOCUS_PRODUCT_ID_UNI        0x0700
0029
0030 #define METROUSB_SET_REQUEST_TYPE   0x40
0031 #define METROUSB_SET_MODEM_CTRL_REQUEST 10
0032 #define METROUSB_SET_BREAK_REQUEST  0x40
0033 #define METROUSB_MCR_NONE       0x08    /* Deactivate DTR and RTS. */
0034 #define METROUSB_MCR_RTS        0x0a    /* Activate RTS. */
0035 #define METROUSB_MCR_DTR        0x09    /* Activate DTR. */
0036 #define WDR_TIMEOUT         5000    /* default urb timeout. */
0037
0038 /* Private data structure. */
0039 struct metrousb_private {
0040     spinlock_t lock;
0041     int throttled;
0042     unsigned long control_state;
0043 };
0044
0045 /* Device table list. */
0046 static const struct usb_device_id id_table[] = {
0047     { USB_DEVICE(FOCUS_VENDOR_ID, FOCUS_PRODUCT_ID_BI) },
0048     { USB_DEVICE(FOCUS_VENDOR_ID, FOCUS_PRODUCT_ID_UNI) },
0049     { USB_DEVICE_INTERFACE_CLASS(0x0c2e, 0x0730, 0xff) },   /* MS7820 */
0050     { }, /* Terminating entry. */
0051 };
0052 MODULE_DEVICE_TABLE(usb, id_table);
0053
0054 /* UNI-Directional mode commands for device configure */
0055 #define UNI_CMD_OPEN    0x80
0056 #define UNI_CMD_CLOSE   0xFF
0057
0058 static int metrousb_is_unidirectional_mode(struct usb_serial *serial)
0059 {
0060     u16 product_id = le16_to_cpu(serial->dev->descriptor.idProduct);
0061
0062     return product_id == FOCUS_PRODUCT_ID_UNI;
0063 }
0064
0065 static int metrousb_calc_num_ports(struct usb_serial *serial,
0066                    struct usb_serial_endpoints *epds)
0067 {
0068     if (metrousb_is_unidirectional_mode(serial)) {
0069         if (epds->num_interrupt_out == 0) {
0070             dev_err(&serial->interface->dev, "interrupt-out endpoint missing\n");
0071             return -ENODEV;
0072         }
0073     }
0074
0075     return 1;
0076 }
0077
0078 static int metrousb_send_unidirectional_cmd(u8 cmd, struct usb_serial_port *port)
0079 {
0080     int ret;
0081     int actual_len;
0082     u8 *buffer_cmd = NULL;
0083
0084     if (!metrousb_is_unidirectional_mode(port->serial))
0085         return 0;
0086
0087     buffer_cmd = kzalloc(sizeof(cmd), GFP_KERNEL);
0088     if (!buffer_cmd)
0089         return -ENOMEM;
0090
0091     *buffer_cmd = cmd;
0092
0093     ret = usb_interrupt_msg(port->serial->dev,
0094         usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
0095         buffer_cmd, sizeof(cmd),
0096         &actual_len, USB_CTRL_SET_TIMEOUT);
0097
0098     kfree(buffer_cmd);
0099
0100     if (ret < 0)
0101         return ret;
0102     else if (actual_len != sizeof(cmd))
0103         return -EIO;
0104     return 0;
0105 }
0106
0107 static void metrousb_read_int_callback(struct urb *urb)
0108 {
0109     struct usb_serial_port *port = urb->context;
0110     struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
0111     unsigned char *data = urb->transfer_buffer;
0112     unsigned long flags;
0113     int throttled = 0;
0114     int result = 0;
0115
0116     dev_dbg(&port->dev, "%s\n", __func__);
0117
0118     switch (urb->status) {
0119     case 0:
0120         /* Success status, read from the port. */
0121         break;
0122     case -ECONNRESET:
0123     case -ENOENT:
0124     case -ESHUTDOWN:
0125         /* urb has been terminated. */
0126         dev_dbg(&port->dev,
0127             "%s - urb shutting down, error code=%d\n",
0128             __func__, urb->status);
0129         return;
0130     default:
0131         dev_dbg(&port->dev,
0132             "%s - non-zero urb received, error code=%d\n",
0133             __func__, urb->status);
0134         goto exit;
0135     }
0136
0137
0138     /* Set the data read from the usb port into the serial port buffer. */
0139     if (urb->actual_length) {
0140         /* Loop through the data copying each byte to the tty layer. */
0141         tty_insert_flip_string(&port->port, data, urb->actual_length);
0142
0143         /* Force the data to the tty layer. */
0144         tty_flip_buffer_push(&port->port);
0145     }
0146
0147     /* Set any port variables. */
0148     spin_lock_irqsave(&metro_priv->lock, flags);
0149     throttled = metro_priv->throttled;
0150     spin_unlock_irqrestore(&metro_priv->lock, flags);
0151
0152     if (throttled)
0153         return;
0154 exit:
0155     /* Try to resubmit the urb. */
0156     result = usb_submit_urb(urb, GFP_ATOMIC);
0157     if (result)
0158         dev_err(&port->dev,
0159             "%s - failed submitting interrupt in urb, error code=%d\n",
0160             __func__, result);
0161 }
0162
0163 static void metrousb_cleanup(struct usb_serial_port *port)
0164 {
0165     usb_kill_urb(port->interrupt_in_urb);
0166
0167     metrousb_send_unidirectional_cmd(UNI_CMD_CLOSE, port);
0168 }
0169
0170 static int metrousb_open(struct tty_struct *tty, struct usb_serial_port *port)
0171 {
0172     struct usb_serial *serial = port->serial;
0173     struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
0174     unsigned long flags;
0175     int result = 0;
0176
0177     /* Set the private data information for the port. */
0178     spin_lock_irqsave(&metro_priv->lock, flags);
0179     metro_priv->control_state = 0;
0180     metro_priv->throttled = 0;
0181     spin_unlock_irqrestore(&metro_priv->lock, flags);
0182
0183     /* Clear the urb pipe. */
0184     usb_clear_halt(serial->dev, port->interrupt_in_urb->pipe);
0185
0186     /* Start reading from the device */
0187     usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
0188               usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
0189                port->interrupt_in_urb->transfer_buffer,
0190                port->interrupt_in_urb->transfer_buffer_length,
0191                metrousb_read_int_callback, port, 1);
0192     result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
0193
0194     if (result) {
0195         dev_err(&port->dev,
0196             "%s - failed submitting interrupt in urb, error code=%d\n",
0197             __func__, result);
0198         return result;
0199     }
0200
0201     /* Send activate cmd to device */
0202     result = metrousb_send_unidirectional_cmd(UNI_CMD_OPEN, port);
0203     if (result) {
0204         dev_err(&port->dev,
0205             "%s - failed to configure device, error code=%d\n",
0206             __func__, result);
0207         goto err_kill_urb;
0208     }
0209
0210     return 0;
0211
0212 err_kill_urb:
0213     usb_kill_urb(port->interrupt_in_urb);
0214
0215     return result;
0216 }
0217
0218 static int metrousb_set_modem_ctrl(struct usb_serial *serial, unsigned int control_state)
0219 {
0220     int retval = 0;
0221     unsigned char mcr = METROUSB_MCR_NONE;
0222
0223     dev_dbg(&serial->dev->dev, "%s - control state = %d\n",
0224         __func__, control_state);
0225
0226     /* Set the modem control value. */
0227     if (control_state & TIOCM_DTR)
0228         mcr |= METROUSB_MCR_DTR;
0229     if (control_state & TIOCM_RTS)
0230         mcr |= METROUSB_MCR_RTS;
0231
0232     /* Send the command to the usb port. */
0233     retval = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
0234                 METROUSB_SET_REQUEST_TYPE, METROUSB_SET_MODEM_CTRL_REQUEST,
0235                 control_state, 0, NULL, 0, WDR_TIMEOUT);
0236     if (retval < 0)
0237         dev_err(&serial->dev->dev,
0238             "%s - set modem ctrl=0x%x failed, error code=%d\n",
0239             __func__, mcr, retval);
0240
0241     return retval;
0242 }
0243
0244 static int metrousb_port_probe(struct usb_serial_port *port)
0245 {
0246     struct metrousb_private *metro_priv;
0247
0248     metro_priv = kzalloc(sizeof(*metro_priv), GFP_KERNEL);
0249     if (!metro_priv)
0250         return -ENOMEM;
0251
0252     spin_lock_init(&metro_priv->lock);
0253
0254     usb_set_serial_port_data(port, metro_priv);
0255
0256     return 0;
0257 }
0258
0259 static void metrousb_port_remove(struct usb_serial_port *port)
0260 {
0261     struct metrousb_private *metro_priv;
0262
0263     metro_priv = usb_get_serial_port_data(port);
0264     kfree(metro_priv);
0265 }
0266
0267 static void metrousb_throttle(struct tty_struct *tty)
0268 {
0269     struct usb_serial_port *port = tty->driver_data;
0270     struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
0271     unsigned long flags;
0272
0273     /* Set the private information for the port to stop reading data. */
0274     spin_lock_irqsave(&metro_priv->lock, flags);
0275     metro_priv->throttled = 1;
0276     spin_unlock_irqrestore(&metro_priv->lock, flags);
0277 }
0278
0279 static int metrousb_tiocmget(struct tty_struct *tty)
0280 {
0281     unsigned long control_state = 0;
0282     struct usb_serial_port *port = tty->driver_data;
0283     struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
0284     unsigned long flags;
0285
0286     spin_lock_irqsave(&metro_priv->lock, flags);
0287     control_state = metro_priv->control_state;
0288     spin_unlock_irqrestore(&metro_priv->lock, flags);
0289
0290     return control_state;
0291 }
0292
0293 static int metrousb_tiocmset(struct tty_struct *tty,
0294                  unsigned int set, unsigned int clear)
0295 {
0296     struct usb_serial_port *port = tty->driver_data;
0297     struct usb_serial *serial = port->serial;
0298     struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
0299     unsigned long flags;
0300     unsigned long control_state = 0;
0301
0302     dev_dbg(&port->dev, "%s - set=%d, clear=%d\n", __func__, set, clear);
0303
0304     spin_lock_irqsave(&metro_priv->lock, flags);
0305     control_state = metro_priv->control_state;
0306
0307     /* Set the RTS and DTR values. */
0308     if (set & TIOCM_RTS)
0309         control_state |= TIOCM_RTS;
0310     if (set & TIOCM_DTR)
0311         control_state |= TIOCM_DTR;
0312     if (clear & TIOCM_RTS)
0313         control_state &= ~TIOCM_RTS;
0314     if (clear & TIOCM_DTR)
0315         control_state &= ~TIOCM_DTR;
0316
0317     metro_priv->control_state = control_state;
0318     spin_unlock_irqrestore(&metro_priv->lock, flags);
0319     return metrousb_set_modem_ctrl(serial, control_state);
0320 }
0321
0322 static void metrousb_unthrottle(struct tty_struct *tty)
0323 {
0324     struct usb_serial_port *port = tty->driver_data;
0325     struct metrousb_private *metro_priv = usb_get_serial_port_data(port);
0326     unsigned long flags;
0327     int result = 0;
0328
0329     /* Set the private information for the port to resume reading data. */
0330     spin_lock_irqsave(&metro_priv->lock, flags);
0331     metro_priv->throttled = 0;
0332     spin_unlock_irqrestore(&metro_priv->lock, flags);
0333
0334     /* Submit the urb to read from the port. */
0335     result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
0336     if (result)
0337         dev_err(&port->dev,
0338             "failed submitting interrupt in urb error code=%d\n",
0339             result);
0340 }
0341
0342 static struct usb_serial_driver metrousb_device = {
0343     .driver = {
0344         .owner =    THIS_MODULE,
0345         .name =     "metro-usb",
0346     },
0347     .description        = "Metrologic USB to Serial",
0348     .id_table       = id_table,
0349     .num_interrupt_in   = 1,
0350     .calc_num_ports     = metrousb_calc_num_ports,
0351     .open           = metrousb_open,
0352     .close          = metrousb_cleanup,
0353     .read_int_callback  = metrousb_read_int_callback,
0354     .port_probe     = metrousb_port_probe,
0355     .port_remove        = metrousb_port_remove,
0356     .throttle       = metrousb_throttle,
0357     .unthrottle     = metrousb_unthrottle,
0358     .tiocmget       = metrousb_tiocmget,
0359     .tiocmset       = metrousb_tiocmset,
0360 };
0361
0362 static struct usb_serial_driver * const serial_drivers[] = {
0363     &metrousb_device,
0364     NULL,
0365 };
0366
0367 module_usb_serial_driver(serial_drivers, id_table);
0368
0369 MODULE_LICENSE("GPL v2");
0370 MODULE_AUTHOR("Philip Nicastro");
0371 MODULE_AUTHOR("Aleksey Babahin <tamerlan311@gmail.com>");
0372 MODULE_DESCRIPTION(DRIVER_DESC);