2 * f_serial.c - generic USB serial function driver
4 * Copyright (C) 2003 Al Borchers (alborchers@steinerpoint.com)
5 * Copyright (C) 2008 by David Brownell
6 * Copyright (C) 2008 by Nokia Corporation
8 * This software is distributed under the terms of the GNU General
9 * Public License ("GPL") as published by the Free Software Foundation,
10 * either version 2 of that License or (at your option) any later version.
13 #include <linux/slab.h>
14 #include <linux/kernel.h>
15 #include <linux/device.h>
18 #include "gadget_chips.h"
22 * This function packages a simple "generic serial" port with no real
23 * control mechanisms, just raw data transfer over two bulk endpoints.
25 * Because it's not standardized, this isn't as interoperable as the
26 * CDC ACM driver. However, for many purposes it's just as functional
27 * if you can arrange appropriate host side drivers.
36 static inline struct f_gser *func_to_gser(struct usb_function *f)
38 return container_of(f, struct f_gser, port.func);
41 /*-------------------------------------------------------------------------*/
43 /* interface descriptor: */
45 static struct usb_interface_descriptor gser_interface_desc __initdata = {
46 .bLength = USB_DT_INTERFACE_SIZE,
47 .bDescriptorType = USB_DT_INTERFACE,
48 /* .bInterfaceNumber = DYNAMIC */
50 .bInterfaceClass = USB_CLASS_VENDOR_SPEC,
51 .bInterfaceSubClass = 0,
52 .bInterfaceProtocol = 0,
53 /* .iInterface = DYNAMIC */
56 /* full speed support: */
58 static struct usb_endpoint_descriptor gser_fs_in_desc __initdata = {
59 .bLength = USB_DT_ENDPOINT_SIZE,
60 .bDescriptorType = USB_DT_ENDPOINT,
61 .bEndpointAddress = USB_DIR_IN,
62 .bmAttributes = USB_ENDPOINT_XFER_BULK,
65 static struct usb_endpoint_descriptor gser_fs_out_desc __initdata = {
66 .bLength = USB_DT_ENDPOINT_SIZE,
67 .bDescriptorType = USB_DT_ENDPOINT,
68 .bEndpointAddress = USB_DIR_OUT,
69 .bmAttributes = USB_ENDPOINT_XFER_BULK,
72 static struct usb_descriptor_header *gser_fs_function[] __initdata = {
73 (struct usb_descriptor_header *) &gser_interface_desc,
74 (struct usb_descriptor_header *) &gser_fs_in_desc,
75 (struct usb_descriptor_header *) &gser_fs_out_desc,
79 /* high speed support: */
81 static struct usb_endpoint_descriptor gser_hs_in_desc __initdata = {
82 .bLength = USB_DT_ENDPOINT_SIZE,
83 .bDescriptorType = USB_DT_ENDPOINT,
84 .bmAttributes = USB_ENDPOINT_XFER_BULK,
85 .wMaxPacketSize = cpu_to_le16(512),
88 static struct usb_endpoint_descriptor gser_hs_out_desc __initdata = {
89 .bLength = USB_DT_ENDPOINT_SIZE,
90 .bDescriptorType = USB_DT_ENDPOINT,
91 .bmAttributes = USB_ENDPOINT_XFER_BULK,
92 .wMaxPacketSize = cpu_to_le16(512),
95 static struct usb_descriptor_header *gser_hs_function[] __initdata = {
96 (struct usb_descriptor_header *) &gser_interface_desc,
97 (struct usb_descriptor_header *) &gser_hs_in_desc,
98 (struct usb_descriptor_header *) &gser_hs_out_desc,
102 static struct usb_endpoint_descriptor gser_ss_in_desc __initdata = {
103 .bLength = USB_DT_ENDPOINT_SIZE,
104 .bDescriptorType = USB_DT_ENDPOINT,
105 .bmAttributes = USB_ENDPOINT_XFER_BULK,
106 .wMaxPacketSize = cpu_to_le16(1024),
109 static struct usb_endpoint_descriptor gser_ss_out_desc __initdata = {
110 .bLength = USB_DT_ENDPOINT_SIZE,
111 .bDescriptorType = USB_DT_ENDPOINT,
112 .bmAttributes = USB_ENDPOINT_XFER_BULK,
113 .wMaxPacketSize = cpu_to_le16(1024),
116 static struct usb_ss_ep_comp_descriptor gser_ss_bulk_comp_desc __initdata = {
117 .bLength = sizeof gser_ss_bulk_comp_desc,
118 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
121 static struct usb_descriptor_header *gser_ss_function[] __initdata = {
122 (struct usb_descriptor_header *) &gser_interface_desc,
123 (struct usb_descriptor_header *) &gser_ss_in_desc,
124 (struct usb_descriptor_header *) &gser_ss_bulk_comp_desc,
125 (struct usb_descriptor_header *) &gser_ss_out_desc,
126 (struct usb_descriptor_header *) &gser_ss_bulk_comp_desc,
130 /* string descriptors: */
132 static struct usb_string gser_string_defs[] = {
133 [0].s = "Generic Serial",
134 { } /* end of list */
137 static struct usb_gadget_strings gser_string_table = {
138 .language = 0x0409, /* en-us */
139 .strings = gser_string_defs,
142 static struct usb_gadget_strings *gser_strings[] = {
147 /*-------------------------------------------------------------------------*/
149 static int gser_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
151 struct f_gser *gser = func_to_gser(f);
152 struct usb_composite_dev *cdev = f->config->cdev;
154 /* we know alt == 0, so this is an activation or a reset */
156 if (gser->port.in->driver_data) {
157 DBG(cdev, "reset generic ttyGS%d\n", gser->port_num);
158 gserial_disconnect(&gser->port);
160 if (!gser->port.in->desc || !gser->port.out->desc) {
161 DBG(cdev, "activate generic ttyGS%d\n", gser->port_num);
162 if (config_ep_by_speed(cdev->gadget, f, gser->port.in) ||
163 config_ep_by_speed(cdev->gadget, f, gser->port.out)) {
164 gser->port.in->desc = NULL;
165 gser->port.out->desc = NULL;
169 gserial_connect(&gser->port, gser->port_num);
173 static void gser_disable(struct usb_function *f)
175 struct f_gser *gser = func_to_gser(f);
176 struct usb_composite_dev *cdev = f->config->cdev;
178 DBG(cdev, "generic ttyGS%d deactivated\n", gser->port_num);
179 gserial_disconnect(&gser->port);
182 /*-------------------------------------------------------------------------*/
184 /* serial function driver setup/binding */
187 gser_bind(struct usb_configuration *c, struct usb_function *f)
189 struct usb_composite_dev *cdev = c->cdev;
190 struct f_gser *gser = func_to_gser(f);
194 /* allocate instance-specific interface IDs */
195 status = usb_interface_id(c, f);
198 gser->data_id = status;
199 gser_interface_desc.bInterfaceNumber = status;
203 /* allocate instance-specific endpoints */
204 ep = usb_ep_autoconfig(cdev->gadget, &gser_fs_in_desc);
208 ep->driver_data = cdev; /* claim */
210 ep = usb_ep_autoconfig(cdev->gadget, &gser_fs_out_desc);
214 ep->driver_data = cdev; /* claim */
216 /* support all relevant hardware speeds... we expect that when
217 * hardware is dual speed, all bulk-capable endpoints work at
220 gser_hs_in_desc.bEndpointAddress = gser_fs_in_desc.bEndpointAddress;
221 gser_hs_out_desc.bEndpointAddress = gser_fs_out_desc.bEndpointAddress;
223 gser_ss_in_desc.bEndpointAddress = gser_fs_in_desc.bEndpointAddress;
224 gser_ss_out_desc.bEndpointAddress = gser_fs_out_desc.bEndpointAddress;
226 status = usb_assign_descriptors(f, gser_fs_function, gser_hs_function,
230 DBG(cdev, "generic ttyGS%d: %s speed IN/%s OUT/%s\n",
232 gadget_is_superspeed(c->cdev->gadget) ? "super" :
233 gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
234 gser->port.in->name, gser->port.out->name);
238 /* we might as well release our claims on endpoints */
240 gser->port.out->driver_data = NULL;
242 gser->port.in->driver_data = NULL;
244 ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
250 gser_unbind(struct usb_configuration *c, struct usb_function *f)
252 usb_free_all_descriptors(f);
253 kfree(func_to_gser(f));
257 * gser_bind_config - add a generic serial function to a configuration
258 * @c: the configuration to support the serial instance
259 * @port_num: /dev/ttyGS* port this interface will use
260 * Context: single threaded during gadget setup
262 * Returns zero on success, else negative errno.
264 * Caller must have called @gserial_setup() with enough ports to
265 * handle all the ones it binds. Caller is also responsible
266 * for calling @gserial_cleanup() before module unload.
268 int __init gser_bind_config(struct usb_configuration *c, u8 port_num)
273 /* REVISIT might want instance-specific strings to help
274 * distinguish instances ...
277 /* maybe allocate device-global string ID */
278 if (gser_string_defs[0].id == 0) {
279 status = usb_string_id(c->cdev);
282 gser_string_defs[0].id = status;
285 /* allocate and initialize one new instance */
286 gser = kzalloc(sizeof *gser, GFP_KERNEL);
290 gser->port_num = port_num;
292 gser->port.func.name = "gser";
293 gser->port.func.strings = gser_strings;
294 gser->port.func.bind = gser_bind;
295 gser->port.func.unbind = gser_unbind;
296 gser->port.func.set_alt = gser_set_alt;
297 gser->port.func.disable = gser_disable;
299 status = usb_add_function(c, &gser->port.func);