]> pilppa.com Git - linux-2.6-omap-h63xx.git/commitdiff
usb gadget: new "CDC Composite" gadget driver
authorDavid Brownell <dbrownell@users.sourceforge.net>
Fri, 20 Jun 2008 01:20:26 +0000 (18:20 -0700)
committerGreg Kroah-Hartman <gregkh@suse.de>
Mon, 21 Jul 2008 22:16:16 +0000 (15:16 -0700)
This is a simple example of a composite gadget, combining two
Communications Class Device (CDC) functions:  ECM and ACM.

This provides a clear example of how the composite gadget framework
is intended to work.  It's surprising that MS-Windows (or at least,
XP and previous) won't "just work" with something this simple...

One /proc/bus/usb/devices listing looks like:

  T:  Bus=03 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 46 Spd=480 MxCh= 0
  D:  Ver= 2.00 Cls=02(comm.) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
  P:  Vendor=0525 ProdID=a4aa Rev= 3.01
  S:  Manufacturer=Linux 2.6.26-rc6-pnut with net2280
  S:  Product=CDC Composite Gadget
  C:* #Ifs= 4 Cfg#= 1 Atr=c0 MxPwr=  2mA
  I:* If#= 0 Alt= 0 #EPs= 1 Cls=02(comm.) Sub=06 Prot=00 Driver=cdc_ether
  E:  Ad=83(I) Atr=03(Int.) MxPS=  16 Ivl=32ms
  I:  If#= 1 Alt= 0 #EPs= 0 Cls=0a(data ) Sub=00 Prot=00 Driver=cdc_ether
  I:* If#= 1 Alt= 1 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=cdc_ether
  E:  Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
  E:  Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
  I:* If#= 2 Alt= 0 #EPs= 1 Cls=02(comm.) Sub=02 Prot=01 Driver=cdc_acm
  E:  Ad=86(I) Atr=03(Int.) MxPS=   8 Ivl=32ms
  I:* If#= 3 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=cdc_acm
  E:  Ad=84(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
  E:  Ad=05(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms

Not all USB peripheral controller hardware can support this driver.
All the highspeed-capable peripheral controllers with drivers now in
the mainline kernel seem to support this, as does omap_udc.  But
many full speed controllers don't have enough endpoints, or (as with
the PXA controllers) don't support altsettings.

Lightly tested.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/usb/gadget/Kconfig
drivers/usb/gadget/Makefile
drivers/usb/gadget/cdc2.c [new file with mode: 0644]

index d6bab0d5f453ba458eec51e044f40e72a5e96a7f..a460706de9840855a6a95f4d45346c4db99f9872 100644 (file)
@@ -586,6 +586,19 @@ config USB_G_PRINTER
          For more information, see Documentation/usb/gadget_printer.txt
          which includes sample code for accessing the device file.
 
+config USB_CDC_COMPOSITE
+       tristate "CDC Composite Device (Ethernet and ACM)"
+       help
+         This driver provides two functions in one configuration:
+         a CDC Ethernet (ECM) link, and a CDC ACM (serial port) link.
+
+         This driver requires four bulk and two interrupt endpoints,
+         plus the ability to handle altsettings.  Not all peripheral
+         controllers are that capable.
+
+         Say "y" to link the driver statically, or "m" to build a
+         dynamically linked module.
+
 # put drivers that need isochronous transfer support (for audio
 # or video class gadget drivers), or specific hardware, here.
 
index 392487ddf902a684ceac805d5fd42316ed9b85fd..fcb5cb9094d905d7e26c35a7dae074fc28b633bd 100644 (file)
@@ -33,6 +33,8 @@ g_file_storage-objs           := file_storage.o usbstring.o config.o \
                                        epautoconf.o
 g_printer-objs                 := printer.o usbstring.o config.o \
                                        epautoconf.o
+g_cdc-objs                     := cdc2.o u_ether.o f_ecm.o \
+                                       u_serial.o f_acm.o $(C_UTILS)
 
 ifeq ($(CONFIG_USB_ETH_RNDIS),y)
        g_ether-objs            += f_rndis.o rndis.o
@@ -45,4 +47,5 @@ obj-$(CONFIG_USB_FILE_STORAGE)        += g_file_storage.o
 obj-$(CONFIG_USB_G_SERIAL)     += g_serial.o
 obj-$(CONFIG_USB_G_PRINTER)    += g_printer.o
 obj-$(CONFIG_USB_MIDI_GADGET)  += g_midi.o
+obj-$(CONFIG_USB_CDC_COMPOSITE) += g_cdc.o
 
diff --git a/drivers/usb/gadget/cdc2.c b/drivers/usb/gadget/cdc2.c
new file mode 100644 (file)
index 0000000..289c752
--- /dev/null
@@ -0,0 +1,246 @@
+/*
+ * cdc2.c -- CDC Composite driver, with ECM and ACM support
+ *
+ * Copyright (C) 2008 David Brownell
+ * Copyright (C) 2008 Nokia Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/utsname.h>
+
+#include "u_ether.h"
+#include "u_serial.h"
+
+
+#define DRIVER_DESC            "CDC Composite Gadget"
+#define DRIVER_VERSION         "King Kamehameha Day 2008"
+
+/*-------------------------------------------------------------------------*/
+
+/* DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
+ * Instead:  allocate your own, using normal USB-IF procedures.
+ */
+
+/* Thanks to NetChip Technologies for donating this product ID.
+ * It's for devices with only this composite CDC configuration.
+ */
+#define CDC_VENDOR_NUM         0x0525  /* NetChip */
+#define CDC_PRODUCT_NUM                0xa4aa  /* CDC Composite: ECM + ACM */
+
+/*-------------------------------------------------------------------------*/
+
+static struct usb_device_descriptor device_desc = {
+       .bLength =              sizeof device_desc,
+       .bDescriptorType =      USB_DT_DEVICE,
+
+       .bcdUSB =               __constant_cpu_to_le16(0x0200),
+
+       .bDeviceClass =         USB_CLASS_COMM,
+       .bDeviceSubClass =      0,
+       .bDeviceProtocol =      0,
+       /* .bMaxPacketSize0 = f(hardware) */
+
+       /* Vendor and product id can be overridden by module parameters.  */
+       .idVendor =             __constant_cpu_to_le16(CDC_VENDOR_NUM),
+       .idProduct =            __constant_cpu_to_le16(CDC_PRODUCT_NUM),
+       /* .bcdDevice = f(hardware) */
+       /* .iManufacturer = DYNAMIC */
+       /* .iProduct = DYNAMIC */
+       /* NO SERIAL NUMBER */
+       .bNumConfigurations =   1,
+};
+
+static struct usb_otg_descriptor otg_descriptor = {
+       .bLength =              sizeof otg_descriptor,
+       .bDescriptorType =      USB_DT_OTG,
+
+       /* REVISIT SRP-only hardware is possible, although
+        * it would not be called "OTG" ...
+        */
+       .bmAttributes =         USB_OTG_SRP | USB_OTG_HNP,
+};
+
+static const struct usb_descriptor_header *otg_desc[] = {
+       (struct usb_descriptor_header *) &otg_descriptor,
+       NULL,
+};
+
+
+/* string IDs are assigned dynamically */
+
+#define STRING_MANUFACTURER_IDX                0
+#define STRING_PRODUCT_IDX             1
+
+static char manufacturer[50];
+
+static struct usb_string strings_dev[] = {
+       [STRING_MANUFACTURER_IDX].s = manufacturer,
+       [STRING_PRODUCT_IDX].s = DRIVER_DESC,
+       {  } /* end of list */
+};
+
+static struct usb_gadget_strings stringtab_dev = {
+       .language       = 0x0409,       /* en-us */
+       .strings        = strings_dev,
+};
+
+static struct usb_gadget_strings *dev_strings[] = {
+       &stringtab_dev,
+       NULL,
+};
+
+static u8 hostaddr[ETH_ALEN];
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * We _always_ have both CDC ECM and CDC ACM functions.
+ */
+static int __init cdc_do_config(struct usb_configuration *c)
+{
+       int     status;
+
+       if (gadget_is_otg(c->cdev->gadget)) {
+               c->descriptors = otg_desc;
+               c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
+       }
+
+       status = ecm_bind_config(c, hostaddr);
+       if (status < 0)
+               return status;
+
+       status = acm_bind_config(c, 0);
+       if (status == 0)
+               return status;
+
+       return 0;
+}
+
+static struct usb_configuration cdc_config_driver = {
+       .label                  = "CDC Composite (ECM + ACM)",
+       .bind                   = cdc_do_config,
+       .bConfigurationValue    = 1,
+       /* .iConfiguration = DYNAMIC */
+       .bmAttributes           = USB_CONFIG_ATT_SELFPOWER,
+       .bMaxPower              = 1,    /* 2 mA, minimal */
+};
+
+/*-------------------------------------------------------------------------*/
+
+static int __init cdc_bind(struct usb_composite_dev *cdev)
+{
+       int                     gcnum;
+       struct usb_gadget       *gadget = cdev->gadget;
+       int                     status;
+
+       if (!can_support_ecm(cdev->gadget)) {
+               ERROR(cdev, "controller '%s' not usable\n", gadget->name);
+               return -EINVAL;
+       }
+
+       /* set up network link layer */
+       status = gether_setup(cdev->gadget, hostaddr);
+       if (status < 0)
+               return status;
+
+       /* set up serial link layer */
+       status = gserial_setup(cdev->gadget, 1);
+       if (status < 0)
+               goto fail0;
+
+       gcnum = usb_gadget_controller_number(gadget);
+       if (gcnum >= 0)
+               device_desc.bcdDevice = cpu_to_le16(0x0300 | gcnum);
+       else {
+               /* We assume that can_support_ecm() tells the truth;
+                * but if the controller isn't recognized at all then
+                * that assumption is a bit more likely to be wrong.
+                */
+               WARN(cdev, "controller '%s' not recognized; trying %s\n",
+                               gadget->name,
+                               cdc_config_driver.label);
+               device_desc.bcdDevice =
+                       __constant_cpu_to_le16(0x0300 | 0x0099);
+       }
+
+
+       /* Allocate string descriptor numbers ... note that string
+        * contents can be overridden by the composite_dev glue.
+        */
+
+       /* device descriptor strings: manufacturer, product */
+       snprintf(manufacturer, sizeof manufacturer, "%s %s with %s",
+               init_utsname()->sysname, init_utsname()->release,
+               gadget->name);
+       status = usb_string_id(cdev);
+       if (status < 0)
+               goto fail1;
+       strings_dev[STRING_MANUFACTURER_IDX].id = status;
+       device_desc.iManufacturer = status;
+
+       status = usb_string_id(cdev);
+       if (status < 0)
+               goto fail1;
+       strings_dev[STRING_PRODUCT_IDX].id = status;
+       device_desc.iProduct = status;
+
+       /* register our configuration */
+       status = usb_add_config(cdev, &cdc_config_driver);
+       if (status < 0)
+               goto fail1;
+
+       INFO(cdev, "%s, version: " DRIVER_VERSION "\n", DRIVER_DESC);
+
+       return 0;
+
+fail1:
+       gserial_cleanup();
+fail0:
+       gether_cleanup();
+       return status;
+}
+
+static int __exit cdc_unbind(struct usb_composite_dev *cdev)
+{
+       gserial_cleanup();
+       gether_cleanup();
+       return 0;
+}
+
+static struct usb_composite_driver cdc_driver = {
+       .name           = "g_cdc",
+       .dev            = &device_desc,
+       .strings        = dev_strings,
+       .bind           = cdc_bind,
+       .unbind         = __exit_p(cdc_unbind),
+};
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_AUTHOR("David Brownell");
+MODULE_LICENSE("GPL");
+
+static int __init init(void)
+{
+       return usb_composite_register(&cdc_driver);
+}
+module_init(init);
+
+static void __exit cleanup(void)
+{
+       usb_composite_unregister(&cdc_driver);
+}
+module_exit(cleanup);