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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/usb/gadget/legacy/mass_storage.c
Initial import
Diffstat (limited to 'drivers/usb/gadget/legacy/mass_storage.c')
-rw-r--r--drivers/usb/gadget/legacy/mass_storage.c276
1 files changed, 276 insertions, 0 deletions
diff --git a/drivers/usb/gadget/legacy/mass_storage.c b/drivers/usb/gadget/legacy/mass_storage.c
new file mode 100644
index 000000000..e7bfb081f
--- /dev/null
+++ b/drivers/usb/gadget/legacy/mass_storage.c
@@ -0,0 +1,276 @@
+/*
+ * mass_storage.c -- Mass Storage USB Gadget
+ *
+ * Copyright (C) 2003-2008 Alan Stern
+ * Copyright (C) 2009 Samsung Electronics
+ * Author: Michal Nazarewicz <mina86@mina86.com>
+ * All rights reserved.
+ *
+ * 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.
+ */
+
+
+/*
+ * The Mass Storage Gadget acts as a USB Mass Storage device,
+ * appearing to the host as a disk drive or as a CD-ROM drive. In
+ * addition to providing an example of a genuinely useful gadget
+ * driver for a USB device, it also illustrates a technique of
+ * double-buffering for increased throughput. Last but not least, it
+ * gives an easy way to probe the behavior of the Mass Storage drivers
+ * in a USB host.
+ *
+ * Since this file serves only administrative purposes and all the
+ * business logic is implemented in f_mass_storage.* file. Read
+ * comments in this file for more detailed description.
+ */
+
+
+#include <linux/kernel.h>
+#include <linux/usb/ch9.h>
+#include <linux/module.h>
+
+/*-------------------------------------------------------------------------*/
+
+#define DRIVER_DESC "Mass Storage Gadget"
+#define DRIVER_VERSION "2009/09/11"
+
+/*
+ * Thanks to NetChip Technologies for donating this product ID.
+ *
+ * DO NOT REUSE THESE IDs with any other driver!! Ever!!
+ * Instead: allocate your own, using normal USB-IF procedures.
+ */
+#define FSG_VENDOR_ID 0x0525 /* NetChip */
+#define FSG_PRODUCT_ID 0xa4a5 /* Linux-USB File-backed Storage Gadget */
+
+#include "f_mass_storage.h"
+
+/*-------------------------------------------------------------------------*/
+USB_GADGET_COMPOSITE_OPTIONS();
+
+static struct usb_device_descriptor msg_device_desc = {
+ .bLength = sizeof msg_device_desc,
+ .bDescriptorType = USB_DT_DEVICE,
+
+ .bcdUSB = cpu_to_le16(0x0200),
+ .bDeviceClass = USB_CLASS_PER_INTERFACE,
+
+ /* Vendor and product id can be overridden by module parameters. */
+ .idVendor = cpu_to_le16(FSG_VENDOR_ID),
+ .idProduct = cpu_to_le16(FSG_PRODUCT_ID),
+ .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,
+};
+
+static struct usb_string strings_dev[] = {
+ [USB_GADGET_MANUFACTURER_IDX].s = "",
+ [USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC,
+ [USB_GADGET_SERIAL_IDX].s = "",
+ { } /* 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 struct usb_function_instance *fi_msg;
+static struct usb_function *f_msg;
+
+/****************************** Configurations ******************************/
+
+static struct fsg_module_parameters mod_data = {
+ .stall = 1
+};
+#ifdef CONFIG_USB_GADGET_DEBUG_FILES
+
+static unsigned int fsg_num_buffers = CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS;
+
+#else
+
+/*
+ * Number of buffers we will use.
+ * 2 is usually enough for good buffering pipeline
+ */
+#define fsg_num_buffers CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS
+
+#endif /* CONFIG_USB_GADGET_DEBUG_FILES */
+
+FSG_MODULE_PARAMETERS(/* no prefix */, mod_data);
+
+static unsigned long msg_registered;
+static void msg_cleanup(void);
+
+static int msg_thread_exits(struct fsg_common *common)
+{
+ msg_cleanup();
+ return 0;
+}
+
+static int msg_do_config(struct usb_configuration *c)
+{
+ struct fsg_opts *opts;
+ int ret;
+
+ if (gadget_is_otg(c->cdev->gadget)) {
+ c->descriptors = otg_desc;
+ c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
+ }
+
+ opts = fsg_opts_from_func_inst(fi_msg);
+
+ f_msg = usb_get_function(fi_msg);
+ if (IS_ERR(f_msg))
+ return PTR_ERR(f_msg);
+
+ ret = fsg_common_run_thread(opts->common);
+ if (ret)
+ goto put_func;
+
+ ret = usb_add_function(c, f_msg);
+ if (ret)
+ goto put_func;
+
+ return 0;
+
+put_func:
+ usb_put_function(f_msg);
+ return ret;
+}
+
+static struct usb_configuration msg_config_driver = {
+ .label = "Linux File-Backed Storage",
+ .bConfigurationValue = 1,
+ .bmAttributes = USB_CONFIG_ATT_SELFPOWER,
+};
+
+
+/****************************** Gadget Bind ******************************/
+
+static int msg_bind(struct usb_composite_dev *cdev)
+{
+ static const struct fsg_operations ops = {
+ .thread_exits = msg_thread_exits,
+ };
+ struct fsg_opts *opts;
+ struct fsg_config config;
+ int status;
+
+ fi_msg = usb_get_function_instance("mass_storage");
+ if (IS_ERR(fi_msg))
+ return PTR_ERR(fi_msg);
+
+ fsg_config_from_params(&config, &mod_data, fsg_num_buffers);
+ opts = fsg_opts_from_func_inst(fi_msg);
+
+ opts->no_configfs = true;
+ status = fsg_common_set_num_buffers(opts->common, fsg_num_buffers);
+ if (status)
+ goto fail;
+
+ status = fsg_common_set_nluns(opts->common, config.nluns);
+ if (status)
+ goto fail_set_nluns;
+
+ fsg_common_set_ops(opts->common, &ops);
+
+ status = fsg_common_set_cdev(opts->common, cdev, config.can_stall);
+ if (status)
+ goto fail_set_cdev;
+
+ fsg_common_set_sysfs(opts->common, true);
+ status = fsg_common_create_luns(opts->common, &config);
+ if (status)
+ goto fail_set_cdev;
+
+ fsg_common_set_inquiry_string(opts->common, config.vendor_name,
+ config.product_name);
+
+ status = usb_string_ids_tab(cdev, strings_dev);
+ if (status < 0)
+ goto fail_string_ids;
+ msg_device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
+
+ status = usb_add_config(cdev, &msg_config_driver, msg_do_config);
+ if (status < 0)
+ goto fail_string_ids;
+
+ usb_composite_overwrite_options(cdev, &coverwrite);
+ dev_info(&cdev->gadget->dev,
+ DRIVER_DESC ", version: " DRIVER_VERSION "\n");
+ set_bit(0, &msg_registered);
+ return 0;
+
+fail_string_ids:
+ fsg_common_remove_luns(opts->common);
+fail_set_cdev:
+ fsg_common_free_luns(opts->common);
+fail_set_nluns:
+ fsg_common_free_buffers(opts->common);
+fail:
+ usb_put_function_instance(fi_msg);
+ return status;
+}
+
+static int msg_unbind(struct usb_composite_dev *cdev)
+{
+ if (!IS_ERR(f_msg))
+ usb_put_function(f_msg);
+
+ if (!IS_ERR(fi_msg))
+ usb_put_function_instance(fi_msg);
+
+ return 0;
+}
+
+/****************************** Some noise ******************************/
+
+static struct usb_composite_driver msg_driver = {
+ .name = "g_mass_storage",
+ .dev = &msg_device_desc,
+ .max_speed = USB_SPEED_SUPER,
+ .needs_serial = 1,
+ .strings = dev_strings,
+ .bind = msg_bind,
+ .unbind = msg_unbind,
+};
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_AUTHOR("Michal Nazarewicz");
+MODULE_LICENSE("GPL");
+
+static int __init msg_init(void)
+{
+ return usb_composite_probe(&msg_driver);
+}
+module_init(msg_init);
+
+static void msg_cleanup(void)
+{
+ if (test_and_clear_bit(0, &msg_registered))
+ usb_composite_unregister(&msg_driver);
+}
+module_exit(msg_cleanup);