USB: serial: refactor and clean up endpoint handling
authorJohan Hovold <johan@kernel.org>
Thu, 21 Aug 2014 17:33:25 +0000 (19:33 +0200)
committerJohan Hovold <johan@kernel.org>
Thu, 16 Mar 2017 09:33:09 +0000 (10:33 +0100)
Refactor and clean up endpoint handling.

This specifically moves the endpoint-descriptor arrays of the stack.

Note that an err_free_epds label is not yet added to avoid a compilation
warning when neither CONFIG_USB_SERIAL_PL2303 or
CONFIG_USB_SERIAL_GENERIC is selected.

Signed-off-by: Johan Hovold <johan@kernel.org>
drivers/usb/serial/usb-serial.c

index e5b859ad15c67a256d93740a0c47b82381713381..09eb639298c8b798ebaed5b5cc624c2e004c851f 100644 (file)
@@ -710,6 +710,53 @@ static const struct tty_port_operations serial_port_ops = {
        .shutdown               = serial_port_shutdown,
 };
 
+struct usb_serial_endpoints {
+       unsigned char num_bulk_in;
+       unsigned char num_bulk_out;
+       unsigned char num_interrupt_in;
+       unsigned char num_interrupt_out;
+       struct usb_endpoint_descriptor *bulk_in[MAX_NUM_PORTS];
+       struct usb_endpoint_descriptor *bulk_out[MAX_NUM_PORTS];
+       struct usb_endpoint_descriptor *interrupt_in[MAX_NUM_PORTS];
+       struct usb_endpoint_descriptor *interrupt_out[MAX_NUM_PORTS];
+};
+
+static void find_endpoints(struct usb_serial *serial,
+                                       struct usb_serial_endpoints *epds)
+{
+       struct device *dev = &serial->interface->dev;
+       struct usb_host_interface *iface_desc;
+       struct usb_endpoint_descriptor *epd;
+       unsigned int i;
+
+       iface_desc = serial->interface->cur_altsetting;
+       for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
+               epd = &iface_desc->endpoint[i].desc;
+
+               if (usb_endpoint_is_bulk_in(epd)) {
+                       dev_dbg(dev, "found bulk in on endpoint %u\n", i);
+                       if (epds->num_bulk_in == MAX_NUM_PORTS)
+                               continue;
+                       epds->bulk_in[epds->num_bulk_in++] = epd;
+               } else if (usb_endpoint_is_bulk_out(epd)) {
+                       dev_dbg(dev, "found bulk out on endpoint %u\n", i);
+                       if (epds->num_bulk_out == MAX_NUM_PORTS)
+                               continue;
+                       epds->bulk_out[epds->num_bulk_out++] = epd;
+               } else if (usb_endpoint_is_int_in(epd)) {
+                       dev_dbg(dev, "found interrupt in on endpoint %u\n", i);
+                       if (epds->num_interrupt_in == MAX_NUM_PORTS)
+                               continue;
+                       epds->interrupt_in[epds->num_interrupt_in++] = epd;
+               } else if (usb_endpoint_is_int_out(epd)) {
+                       dev_dbg(dev, "found interrupt out on endpoint %u\n", i);
+                       if (epds->num_interrupt_out == MAX_NUM_PORTS)
+                               continue;
+                       epds->interrupt_out[epds->num_interrupt_out++] = epd;
+               }
+       }
+}
+
 static int usb_serial_probe(struct usb_interface *interface,
                               const struct usb_device_id *id)
 {
@@ -717,21 +764,13 @@ static int usb_serial_probe(struct usb_interface *interface,
        struct usb_device *dev = interface_to_usbdev(interface);
        struct usb_serial *serial = NULL;
        struct usb_serial_port *port;
-       struct usb_host_interface *iface_desc;
        struct usb_endpoint_descriptor *endpoint;
-       struct usb_endpoint_descriptor *interrupt_in_endpoint[MAX_NUM_PORTS];
-       struct usb_endpoint_descriptor *interrupt_out_endpoint[MAX_NUM_PORTS];
-       struct usb_endpoint_descriptor *bulk_in_endpoint[MAX_NUM_PORTS];
-       struct usb_endpoint_descriptor *bulk_out_endpoint[MAX_NUM_PORTS];
+       struct usb_serial_endpoints *epds;
        struct usb_serial_driver *type = NULL;
        int retval;
        int buffer_size;
        int i;
        int j;
-       unsigned char num_interrupt_in = 0;
-       unsigned char num_interrupt_out = 0;
-       unsigned char num_bulk_in = 0;
-       unsigned char num_bulk_out = 0;
        int num_ports = 0;
        unsigned char max_endpoints;
 
@@ -770,50 +809,14 @@ static int usb_serial_probe(struct usb_interface *interface,
        }
 
        /* descriptor matches, let's find the endpoints needed */
-       /* check out the endpoints */
-       iface_desc = interface->cur_altsetting;
-       for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
-               endpoint = &iface_desc->endpoint[i].desc;
-
-               if (usb_endpoint_is_bulk_in(endpoint)) {
-                       /* we found a bulk in endpoint */
-                       dev_dbg(ddev, "found bulk in on endpoint %d\n", i);
-                       if (num_bulk_in < MAX_NUM_PORTS) {
-                               bulk_in_endpoint[num_bulk_in] = endpoint;
-                               ++num_bulk_in;
-                       }
-               }
-
-               if (usb_endpoint_is_bulk_out(endpoint)) {
-                       /* we found a bulk out endpoint */
-                       dev_dbg(ddev, "found bulk out on endpoint %d\n", i);
-                       if (num_bulk_out < MAX_NUM_PORTS) {
-                               bulk_out_endpoint[num_bulk_out] = endpoint;
-                               ++num_bulk_out;
-                       }
-               }
-
-               if (usb_endpoint_is_int_in(endpoint)) {
-                       /* we found a interrupt in endpoint */
-                       dev_dbg(ddev, "found interrupt in on endpoint %d\n", i);
-                       if (num_interrupt_in < MAX_NUM_PORTS) {
-                               interrupt_in_endpoint[num_interrupt_in] =
-                                               endpoint;
-                               ++num_interrupt_in;
-                       }
-               }
-
-               if (usb_endpoint_is_int_out(endpoint)) {
-                       /* we found an interrupt out endpoint */
-                       dev_dbg(ddev, "found interrupt out on endpoint %d\n", i);
-                       if (num_interrupt_out < MAX_NUM_PORTS) {
-                               interrupt_out_endpoint[num_interrupt_out] =
-                                               endpoint;
-                               ++num_interrupt_out;
-                       }
-               }
+       epds = kzalloc(sizeof(*epds), GFP_KERNEL);
+       if (!epds) {
+               retval = -ENOMEM;
+               goto err_put_serial;
        }
 
+       find_endpoints(serial, epds);
+
 #if IS_ENABLED(CONFIG_USB_SERIAL_PL2303)
        /* BEGIN HORRIBLE HACK FOR PL2303 */
        /* this is needed due to the looney way its endpoints are set up */
@@ -826,6 +829,8 @@ static int usb_serial_probe(struct usb_interface *interface,
            ((le16_to_cpu(dev->descriptor.idVendor) == SIEMENS_VENDOR_ID) &&
             (le16_to_cpu(dev->descriptor.idProduct) == SIEMENS_PRODUCT_ID_EF81))) {
                if (interface != dev->actconfig->interface[0]) {
+                       struct usb_host_interface *iface_desc;
+
                        /* check out the endpoints of the other interface*/
                        iface_desc = dev->actconfig->interface[0]->cur_altsetting;
                        for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
@@ -833,10 +838,8 @@ static int usb_serial_probe(struct usb_interface *interface,
                                if (usb_endpoint_is_int_in(endpoint)) {
                                        /* we found a interrupt in endpoint */
                                        dev_dbg(ddev, "found interrupt in for Prolific device on separate interface\n");
-                                       if (num_interrupt_in < MAX_NUM_PORTS) {
-                                               interrupt_in_endpoint[num_interrupt_in] = endpoint;
-                                               ++num_interrupt_in;
-                                       }
+                                       if (epds->num_interrupt_in < ARRAY_SIZE(epds->interrupt_in))
+                                               epds->interrupt_in[epds->num_interrupt_in++] = endpoint;
                                }
                        }
                }
@@ -845,9 +848,10 @@ static int usb_serial_probe(struct usb_interface *interface,
                 * If not, give up now and hope this hack will work
                 * properly during a later invocation of usb_serial_probe
                 */
-               if (num_bulk_in == 0 || num_bulk_out == 0) {
+               if (epds->num_bulk_in == 0 || epds->num_bulk_out == 0) {
                        dev_info(ddev, "PL-2303 hack: descriptors matched but endpoints did not\n");
                        retval = -ENODEV;
+                       kfree(epds);
                        goto err_put_serial;
                }
        }
@@ -856,10 +860,11 @@ static int usb_serial_probe(struct usb_interface *interface,
 
 #ifdef CONFIG_USB_SERIAL_GENERIC
        if (type == &usb_serial_generic_device) {
-               num_ports = num_bulk_out;
+               num_ports = epds->num_bulk_out;
                if (num_ports == 0) {
                        dev_err(ddev, "Generic device with no bulk out, not allowed.\n");
                        retval = -EIO;
+                       kfree(epds);
                        goto err_put_serial;
                }
                dev_info(ddev, "The \"generic\" usb-serial driver is only for testing and one-off prototypes.\n");
@@ -880,10 +885,10 @@ static int usb_serial_probe(struct usb_interface *interface,
        }
 
        serial->num_ports = (unsigned char)num_ports;
-       serial->num_bulk_in = num_bulk_in;
-       serial->num_bulk_out = num_bulk_out;
-       serial->num_interrupt_in = num_interrupt_in;
-       serial->num_interrupt_out = num_interrupt_out;
+       serial->num_bulk_in = epds->num_bulk_in;
+       serial->num_bulk_out = epds->num_bulk_out;
+       serial->num_interrupt_in = epds->num_interrupt_in;
+       serial->num_interrupt_out = epds->num_interrupt_out;
 
        /* found all that we need */
        dev_info(ddev, "%s converter detected\n", type->description);
@@ -891,9 +896,9 @@ static int usb_serial_probe(struct usb_interface *interface,
        /* create our ports, we need as many as the max endpoints */
        /* we don't use num_ports here because some devices have more
           endpoint pairs than ports */
-       max_endpoints = max(num_bulk_in, num_bulk_out);
-       max_endpoints = max(max_endpoints, num_interrupt_in);
-       max_endpoints = max(max_endpoints, num_interrupt_out);
+       max_endpoints = max(epds->num_bulk_in, epds->num_bulk_out);
+       max_endpoints = max(max_endpoints, epds->num_interrupt_in);
+       max_endpoints = max(max_endpoints, epds->num_interrupt_out);
        max_endpoints = max(max_endpoints, serial->num_ports);
        serial->num_port_pointers = max_endpoints;
 
@@ -919,8 +924,8 @@ static int usb_serial_probe(struct usb_interface *interface,
        }
 
        /* set up the endpoint information */
-       for (i = 0; i < num_bulk_in; ++i) {
-               endpoint = bulk_in_endpoint[i];
+       for (i = 0; i < epds->num_bulk_in; ++i) {
+               endpoint = epds->bulk_in[i];
                port = serial->port[i];
                buffer_size = max_t(int, serial->type->bulk_in_size,
                                usb_endpoint_maxp(endpoint));
@@ -948,8 +953,8 @@ static int usb_serial_probe(struct usb_interface *interface,
                port->bulk_in_buffer = port->bulk_in_buffers[0];
        }
 
-       for (i = 0; i < num_bulk_out; ++i) {
-               endpoint = bulk_out_endpoint[i];
+       for (i = 0; i < epds->num_bulk_out; ++i) {
+               endpoint = epds->bulk_out[i];
                port = serial->port[i];
                if (kfifo_alloc(&port->write_fifo, PAGE_SIZE, GFP_KERNEL))
                        goto probe_error;
@@ -981,8 +986,8 @@ static int usb_serial_probe(struct usb_interface *interface,
        }
 
        if (serial->type->read_int_callback) {
-               for (i = 0; i < num_interrupt_in; ++i) {
-                       endpoint = interrupt_in_endpoint[i];
+               for (i = 0; i < epds->num_interrupt_in; ++i) {
+                       endpoint = epds->interrupt_in[i];
                        port = serial->port[i];
                        port->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
                        if (!port->interrupt_in_urb)
@@ -1001,13 +1006,13 @@ static int usb_serial_probe(struct usb_interface *interface,
                                serial->type->read_int_callback, port,
                                endpoint->bInterval);
                }
-       } else if (num_interrupt_in) {
+       } else if (epds->num_interrupt_in) {
                dev_dbg(ddev, "The device claims to support interrupt in transfers, but read_int_callback is not defined\n");
        }
 
        if (serial->type->write_int_callback) {
-               for (i = 0; i < num_interrupt_out; ++i) {
-                       endpoint = interrupt_out_endpoint[i];
+               for (i = 0; i < epds->num_interrupt_out; ++i) {
+                       endpoint = epds->interrupt_out[i];
                        port = serial->port[i];
                        port->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
                        if (!port->interrupt_out_urb)
@@ -1027,7 +1032,7 @@ static int usb_serial_probe(struct usb_interface *interface,
                                serial->type->write_int_callback, port,
                                endpoint->bInterval);
                }
-       } else if (num_interrupt_out) {
+       } else if (epds->num_interrupt_out) {
                dev_dbg(ddev, "The device claims to support interrupt out transfers, but write_int_callback is not defined\n");
        }
 
@@ -1077,6 +1082,7 @@ static int usb_serial_probe(struct usb_interface *interface,
        if (num_ports > 0)
                usb_serial_console_init(serial->port[0]->minor);
 exit:
+       kfree(epds);
        module_put(type->driver.owner);
        return 0;