usb: gadget: add new usb gadget for ACM and mass storage

This driver provides two functions in one configuration:
a mass storage, and a ACM (serial port) link.
Heavily based on multi.c and cdc2.c
Signed-off-by: Klaus Schwarzkopf <schwarzkopf@sensortherm.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/Kconfig

@@ -873,6 +873,16 @@ config USB_G_NOKIA
 	  It's only really useful for N900 hardware. If you're building
 	  a kernel for N900, say Y or M here. If unsure, say N.
 
+config USB_G_ACM_MS
+	tristate "CDC Composite Device (ACM and mass storage)"
+	depends on BLOCK
+	help
+	  This driver provides two functions in one configuration:
+	  a mass storage, and a CDC ACM (serial port) link.
+
+	  Say "y" to link the driver statically, or "m" to build a
+	  dynamically linked module called "g_acm_ms".
+
 config USB_G_MULTI
 	tristate "Multifunction Composite Gadget (EXPERIMENTAL)"
 	depends on BLOCK && NET

drivers/usb/gadget/Makefile

@@ -51,6 +51,7 @@ g_dbgp-y			:= dbgp.o
 g_nokia-y			:= nokia.o
 g_webcam-y			:= webcam.o
 g_ncm-y				:= ncm.o
+g_acm_ms-y			:= acm_ms.o
 
 obj-$(CONFIG_USB_ZERO)		+= g_zero.o
 obj-$(CONFIG_USB_AUDIO)		+= g_audio.o
@@ -69,3 +70,4 @@ obj-$(CONFIG_USB_G_MULTI)	+= g_multi.o
 obj-$(CONFIG_USB_G_NOKIA)	+= g_nokia.o
 obj-$(CONFIG_USB_G_WEBCAM)	+= g_webcam.o
 obj-$(CONFIG_USB_G_NCM)		+= g_ncm.o
+obj-$(CONFIG_USB_G_ACM_MS)	+= g_acm_ms.o

drivers/usb/gadget/acm_ms.c

+/*
+ * acm_ms.c -- Composite driver, with ACM and mass storage support
+ *
+ * Copyright (C) 2008 David Brownell
+ * Copyright (C) 2008 Nokia Corporation
+ * Author: David Brownell
+ * Modified: Klaus Schwarzkopf <schwarzkopf@sensortherm.de>
+ *
+ * Heavily based on multi.c and cdc2.c
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/utsname.h>
+
+#include "u_serial.h"
+
+#define DRIVER_DESC		"Composite Gadget (ACM + MS)"
+#define DRIVER_VERSION		"2011/10/10"
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
+ * Instead:  allocate your own, using normal USB-IF procedures.
+ */
+#define ACM_MS_VENDOR_NUM	0x1d6b	/* Linux Foundation */
+#define ACM_MS_PRODUCT_NUM	0x0106	/* Composite Gadget: ACM + MS*/
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * Kbuild is not very cooperative with respect to linking separately
+ * compiled library objects into one module.  So for now we won't use
+ * separate compilation ... ensuring init/exit sections work to shrink
+ * the runtime footprint, and giving us at least some parts of what
+ * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
+ */
+
+#include "composite.c"
+#include "usbstring.c"
+#include "config.c"
+#include "epautoconf.c"
+#include "u_serial.c"
+#include "f_acm.c"
+#include "f_mass_storage.c"
+
+/*-------------------------------------------------------------------------*/
+
+static struct usb_device_descriptor device_desc = {
+	.bLength =		sizeof device_desc,
+	.bDescriptorType =	USB_DT_DEVICE,
+
+	.bcdUSB =		cpu_to_le16(0x0200),
+
+	.bDeviceClass =		USB_CLASS_MISC /* 0xEF */,
+	.bDeviceSubClass =	2,
+	.bDeviceProtocol =	1,
+
+	/* .bMaxPacketSize0 = f(hardware) */
+
+	/* Vendor and product id can be overridden by module parameters.  */
+	.idVendor =		cpu_to_le16(ACM_MS_VENDOR_NUM),
+	.idProduct =		cpu_to_le16(ACM_MS_PRODUCT_NUM),
+	/* .bcdDevice = f(hardware) */
+	/* .iManufacturer = DYNAMIC */
+	/* .iProduct = DYNAMIC */
+	/* NO SERIAL NUMBER */
+	/*.bNumConfigurations =	DYNAMIC*/
+};
+
+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,
+};
+
+/****************************** Configurations ******************************/
+
+static struct fsg_module_parameters fsg_mod_data = { .stall = 1 };
+FSG_MODULE_PARAMETERS(/* no prefix */, fsg_mod_data);
+
+static struct fsg_common fsg_common;
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * We _always_ have both ACM and mass storage functions.
+ */
+static int __init acm_ms_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 = acm_bind_config(c, 0);
+	if (status < 0)
+		return status;
+
+	status = fsg_bind_config(c->cdev, c, &fsg_common);
+	if (status < 0)
+		return status;
+
+	return 0;
+}
+
+static struct usb_configuration acm_ms_config_driver = {
+	.label			= DRIVER_DESC,
+	.bConfigurationValue	= 1,
+	/* .iConfiguration = DYNAMIC */
+	.bmAttributes		= USB_CONFIG_ATT_SELFPOWER,
+};
+
+/*-------------------------------------------------------------------------*/
+
+static int __init acm_ms_bind(struct usb_composite_dev *cdev)
+{
+	int			gcnum;
+	struct usb_gadget	*gadget = cdev->gadget;
+	int			status;
+	void			*retp;
+
+	/* set up serial link layer */
+	status = gserial_setup(cdev->gadget, 1);
+	if (status < 0)
+		return status;
+
+	/* set up mass storage function */
+	retp = fsg_common_from_params(&fsg_common, cdev, &fsg_mod_data);
+	if (IS_ERR(retp)) {
+		status = PTR_ERR(retp);
+		goto fail0;
+	}
+
+	/* set bcdDevice */
+	gcnum = usb_gadget_controller_number(gadget);
+	if (gcnum >= 0) {
+		device_desc.bcdDevice = cpu_to_le16(0x0300 | gcnum);
+	} else {
+		WARNING(cdev, "controller '%s' not recognized; trying %s\n",
+				gadget->name,
+				acm_ms_config_driver.label);
+		device_desc.bcdDevice =
+			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, &acm_ms_config_driver, acm_ms_do_config);
+	if (status < 0)
+		goto fail1;
+
+	dev_info(&gadget->dev, "%s, version: " DRIVER_VERSION "\n",
+			DRIVER_DESC);
+	fsg_common_put(&fsg_common);
+	return 0;
+
+	/* error recovery */
+fail1:
+	fsg_common_put(&fsg_common);
+fail0:
+	gserial_cleanup();
+	return status;
+}
+
+static int __exit acm_ms_unbind(struct usb_composite_dev *cdev)
+{
+	gserial_cleanup();
+
+	return 0;
+}
+
+static struct usb_composite_driver acm_ms_driver = {
+	.name		= "g_acm_ms",
+	.dev		= &device_desc,
+	.strings	= dev_strings,
+	.unbind		= __exit_p(acm_ms_unbind),
+};
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_AUTHOR("Klaus Schwarzkopf <schwarzkopf@sensortherm.de>");
+MODULE_LICENSE("GPL v2");
+
+static int __init init(void)
+{
+	return usb_composite_probe(&acm_ms_driver, acm_ms_bind);
+}
+module_init(init);
+
+static void __exit cleanup(void)
+{
+	usb_composite_unregister(&acm_ms_driver);
+}
+module_exit(cleanup);