drivers/usb/gadget/hid.c

   1 /*
   2  * hid.c -- HID Composite driver
   3  *
   4  * Based on multi.c
   5  *
   6  * Copyright (C) 2010 Fabien Chouteau <fabien.chouteau@barco.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  */
  13
  14
  15 #include <linux/kernel.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/list.h>
  18 #include <linux/module.h>
  19 #include <linux/usb/composite.h>
  20
  21 #include "gadget_chips.h"
  22 #define DRIVER_DESC             "HID Gadget"
  23 #define DRIVER_VERSION          "2010/03/16"
  24
  25 /*-------------------------------------------------------------------------*/
  26
  27 #define HIDG_VENDOR_NUM         0x0525  /* XXX NetChip */
  28 #define HIDG_PRODUCT_NUM        0xa4ac  /* Linux-USB HID gadget */
  29
  30 /*-------------------------------------------------------------------------*/
  31
  32 /*
  33  * kbuild is not very cooperative with respect to linking separately
  34  * compiled library objects into one module.  So for now we won't use
  35  * separate compilation ... ensuring init/exit sections work to shrink
  36  * the runtime footprint, and giving us at least some parts of what
  37  * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
  38  */
  39 #include "f_hid.c"
  40
  41
  42 struct hidg_func_node {
  43         struct list_head node;
  44         struct hidg_func_descriptor *func;
  45 };
  46
  47 static LIST_HEAD(hidg_func_list);
  48
  49 /*-------------------------------------------------------------------------*/
  50 USB_GADGET_COMPOSITE_OPTIONS();
  51
  52 static struct usb_device_descriptor device_desc = {
  53         .bLength =              sizeof device_desc,
  54         .bDescriptorType =      USB_DT_DEVICE,
  55
  56         .bcdUSB =               cpu_to_le16(0x0200),
  57
  58         /* .bDeviceClass =              USB_CLASS_COMM, */
  59         /* .bDeviceSubClass =   0, */
  60         /* .bDeviceProtocol =   0, */
  61         .bDeviceClass =         USB_CLASS_PER_INTERFACE,
  62         .bDeviceSubClass =      0,
  63         .bDeviceProtocol =      0,
  64         /* .bMaxPacketSize0 = f(hardware) */
  65
  66         /* Vendor and product id can be overridden by module parameters.  */
  67         .idVendor =             cpu_to_le16(HIDG_VENDOR_NUM),
  68         .idProduct =            cpu_to_le16(HIDG_PRODUCT_NUM),
  69         /* .bcdDevice = f(hardware) */
  70         /* .iManufacturer = DYNAMIC */
  71         /* .iProduct = DYNAMIC */
  72         /* NO SERIAL NUMBER */
  73         .bNumConfigurations =   1,
  74 };
  75
  76 static struct usb_otg_descriptor otg_descriptor = {
  77         .bLength =              sizeof otg_descriptor,
  78         .bDescriptorType =      USB_DT_OTG,
  79
  80         /* REVISIT SRP-only hardware is possible, although
  81          * it would not be called "OTG" ...
  82          */
  83         .bmAttributes =         USB_OTG_SRP | USB_OTG_HNP,
  84 };
  85
  86 static const struct usb_descriptor_header *otg_desc[] = {
  87         (struct usb_descriptor_header *) &otg_descriptor,
  88         NULL,
  89 };
  90
  91
  92 /* string IDs are assigned dynamically */
  93 static struct usb_string strings_dev[] = {
  94         [USB_GADGET_MANUFACTURER_IDX].s = "",
  95         [USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC,
  96         [USB_GADGET_SERIAL_IDX].s = "",
  97         {  } /* end of list */
  98 };
  99
 100 static struct usb_gadget_strings stringtab_dev = {
 101         .language       = 0x0409,       /* en-us */
 102         .strings        = strings_dev,
 103 };
 104
 105 static struct usb_gadget_strings *dev_strings[] = {
 106         &stringtab_dev,
 107         NULL,
 108 };
 109
 110
 111
 112 /****************************** Configurations ******************************/
 113
 114 static int __init do_config(struct usb_configuration *c)
 115 {
 116         struct hidg_func_node *e;
 117         int func = 0, status = 0;
 118
 119         if (gadget_is_otg(c->cdev->gadget)) {
 120                 c->descriptors = otg_desc;
 121                 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
 122         }
 123
 124         list_for_each_entry(e, &hidg_func_list, node) {
 125                 status = hidg_bind_config(c, e->func, func++);
 126                 if (status)
 127                         break;
 128         }
 129
 130         return status;
 131 }
 132
 133 static struct usb_configuration config_driver = {
 134         .label                  = "HID Gadget",
 135         .bConfigurationValue    = 1,
 136         /* .iConfiguration = DYNAMIC */
 137         .bmAttributes           = USB_CONFIG_ATT_SELFPOWER,
 138 };
 139
 140 /****************************** Gadget Bind ******************************/
 141
 142 static int __init hid_bind(struct usb_composite_dev *cdev)
 143 {
 144         struct usb_gadget *gadget = cdev->gadget;
 145         struct list_head *tmp;
 146         int status, funcs = 0;
 147
 148         list_for_each(tmp, &hidg_func_list)
 149                 funcs++;
 150
 151         if (!funcs)
 152                 return -ENODEV;
 153
 154         /* set up HID */
 155         status = ghid_setup(cdev->gadget, funcs);
 156         if (status < 0)
 157                 return status;
 158
 159         /* Allocate string descriptor numbers ... note that string
 160          * contents can be overridden by the composite_dev glue.
 161          */
 162
 163         status = usb_string_ids_tab(cdev, strings_dev);
 164         if (status < 0)
 165                 return status;
 166         device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
 167         device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
 168
 169         /* register our configuration */
 170         status = usb_add_config(cdev, &config_driver, do_config);
 171         if (status < 0)
 172                 return status;
 173
 174         usb_composite_overwrite_options(cdev, &coverwrite);
 175         dev_info(&gadget->dev, DRIVER_DESC ", version: " DRIVER_VERSION "\n");
 176
 177         return 0;
 178 }
 179
 180 static int __exit hid_unbind(struct usb_composite_dev *cdev)
 181 {
 182         ghid_cleanup();
 183         return 0;
 184 }
 185
 186 static int __init hidg_plat_driver_probe(struct platform_device *pdev)
 187 {
 188         struct hidg_func_descriptor *func = pdev->dev.platform_data;
 189         struct hidg_func_node *entry;
 190
 191         if (!func) {
 192                 dev_err(&pdev->dev, "Platform data missing\n");
 193                 return -ENODEV;
 194         }
 195
 196         entry = kzalloc(sizeof(*entry), GFP_KERNEL);
 197         if (!entry)
 198                 return -ENOMEM;
 199
 200         entry->func = func;
 201         list_add_tail(&entry->node, &hidg_func_list);
 202
 203         return 0;
 204 }
 205
 206 static int hidg_plat_driver_remove(struct platform_device *pdev)
 207 {
 208         struct hidg_func_node *e, *n;
 209
 210         list_for_each_entry_safe(e, n, &hidg_func_list, node) {
 211                 list_del(&e->node);
 212                 kfree(e);
 213         }
 214
 215         return 0;
 216 }
 217
 218
 219 /****************************** Some noise ******************************/
 220
 221
 222 static __refdata struct usb_composite_driver hidg_driver = {
 223         .name           = "g_hid",
 224         .dev            = &device_desc,
 225         .strings        = dev_strings,
 226         .max_speed      = USB_SPEED_HIGH,
 227         .bind           = hid_bind,
 228         .unbind         = __exit_p(hid_unbind),
 229 };
 230
 231 static struct platform_driver hidg_plat_driver = {
 232         .remove         = hidg_plat_driver_remove,
 233         .driver         = {
 234                 .owner  = THIS_MODULE,
 235                 .name   = "hidg",
 236         },
 237 };
 238
 239
 240 MODULE_DESCRIPTION(DRIVER_DESC);
 241 MODULE_AUTHOR("Fabien Chouteau, Peter Korsgaard");
 242 MODULE_LICENSE("GPL");
 243
 244 static int __init hidg_init(void)
 245 {
 246         int status;
 247
 248         status = platform_driver_probe(&hidg_plat_driver,
 249                                 hidg_plat_driver_probe);
 250         if (status < 0)
 251                 return status;
 252
 253         status = usb_composite_probe(&hidg_driver);
 254         if (status < 0)
 255                 platform_driver_unregister(&hidg_plat_driver);
 256
 257         return status;
 258 }
 259 module_init(hidg_init);
 260
 261 static void __exit hidg_cleanup(void)
 262 {
 263         platform_driver_unregister(&hidg_plat_driver);
 264         usb_composite_unregister(&hidg_driver);
 265 }
 266 module_exit(hidg_cleanup);