[linux-block.git] / drivers / usb / gadget / f_serial.c

/*
 * f_serial.c - generic USB serial function driver
 *
 * Copyright (C) 2003 Al Borchers (alborchers@steinerpoint.com)
 * Copyright (C) 2008 by David Brownell
 * Copyright (C) 2008 by Nokia Corporation
 *
 * This software is distributed under the terms of the GNU General
 * Public License ("GPL") as published by the Free Software Foundation,
 * either version 2 of that License or (at your option) any later version.
 */

#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/device.h>

#include "u_serial.h"
#include "gadget_chips.h"


/*
 * This function packages a simple "generic serial" port with no real
 * control mechanisms, just raw data transfer over two bulk endpoints.
 *
 * Because it's not standardized, this isn't as interoperable as the
 * CDC ACM driver.  However, for many purposes it's just as functional
 * if you can arrange appropriate host side drivers.
 */

struct gser_descs {
	struct usb_endpoint_descriptor	*in;
	struct usb_endpoint_descriptor	*out;
};

struct f_gser {
	struct gserial			port;
	u8				data_id;
	u8				port_num;

	struct gser_descs		fs;
	struct gser_descs		hs;
};

static inline struct f_gser *func_to_gser(struct usb_function *f)
{
	return container_of(f, struct f_gser, port.func);
}

/*-------------------------------------------------------------------------*/

/* interface descriptor: */

static struct usb_interface_descriptor gser_interface_desc __initdata = {
	.bLength =		USB_DT_INTERFACE_SIZE,
	.bDescriptorType =	USB_DT_INTERFACE,
	/* .bInterfaceNumber = DYNAMIC */
	.bNumEndpoints =	2,
	.bInterfaceClass =	USB_CLASS_VENDOR_SPEC,
	.bInterfaceSubClass =	0,
	.bInterfaceProtocol =	0,
	/* .iInterface = DYNAMIC */
};

/* full speed support: */

static struct usb_endpoint_descriptor gser_fs_in_desc __initdata = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,
	.bEndpointAddress =	USB_DIR_IN,
	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
};

static struct usb_endpoint_descriptor gser_fs_out_desc __initdata = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,
	.bEndpointAddress =	USB_DIR_OUT,
	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
};

static struct usb_descriptor_header *gser_fs_function[] __initdata = {
	(struct usb_descriptor_header *) &gser_interface_desc,
	(struct usb_descriptor_header *) &gser_fs_in_desc,
	(struct usb_descriptor_header *) &gser_fs_out_desc,
	NULL,
};

/* high speed support: */

static struct usb_endpoint_descriptor gser_hs_in_desc __initdata = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,
	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
	.wMaxPacketSize =	cpu_to_le16(512),
};

static struct usb_endpoint_descriptor gser_hs_out_desc __initdata = {
	.bLength =		USB_DT_ENDPOINT_SIZE,
	.bDescriptorType =	USB_DT_ENDPOINT,
	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
	.wMaxPacketSize =	cpu_to_le16(512),
};

static struct usb_descriptor_header *gser_hs_function[] __initdata = {
	(struct usb_descriptor_header *) &gser_interface_desc,
	(struct usb_descriptor_header *) &gser_hs_in_desc,
	(struct usb_descriptor_header *) &gser_hs_out_desc,
	NULL,
};

/* string descriptors: */

static struct usb_string gser_string_defs[] = {
	[0].s = "Generic Serial",
	{  } /* end of list */
};

static struct usb_gadget_strings gser_string_table = {
	.language =		0x0409,	/* en-us */
	.strings =		gser_string_defs,
};

static struct usb_gadget_strings *gser_strings[] = {
	&gser_string_table,
	NULL,
};

/*-------------------------------------------------------------------------*/

static int gser_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
{
	struct f_gser		*gser = func_to_gser(f);
	struct usb_composite_dev *cdev = f->config->cdev;

	/* we know alt == 0, so this is an activation or a reset */

	if (gser->port.in->driver_data) {
		DBG(cdev, "reset generic ttyGS%d\n", gser->port_num);
		gserial_disconnect(&gser->port);
	} else {
		DBG(cdev, "activate generic ttyGS%d\n", gser->port_num);
		gser->port.in_desc = ep_choose(cdev->gadget,
				gser->hs.in, gser->fs.in);
		gser->port.out_desc = ep_choose(cdev->gadget,
				gser->hs.out, gser->fs.out);
	}
	gserial_connect(&gser->port, gser->port_num);
	return 0;
}

static void gser_disable(struct usb_function *f)
{
	struct f_gser	*gser = func_to_gser(f);
	struct usb_composite_dev *cdev = f->config->cdev;

	DBG(cdev, "generic ttyGS%d deactivated\n", gser->port_num);
	gserial_disconnect(&gser->port);
}

/*-------------------------------------------------------------------------*/

/* serial function driver setup/binding */

static int __init
gser_bind(struct usb_configuration *c, struct usb_function *f)
{
	struct usb_composite_dev *cdev = c->cdev;
	struct f_gser		*gser = func_to_gser(f);
	int			status;
	struct usb_ep		*ep;

	/* allocate instance-specific interface IDs */
	status = usb_interface_id(c, f);
	if (status < 0)
		goto fail;
	gser->data_id = status;
	gser_interface_desc.bInterfaceNumber = status;

	status = -ENODEV;

	/* allocate instance-specific endpoints */
	ep = usb_ep_autoconfig(cdev->gadget, &gser_fs_in_desc);
	if (!ep)
		goto fail;
	gser->port.in = ep;
	ep->driver_data = cdev;	/* claim */

	ep = usb_ep_autoconfig(cdev->gadget, &gser_fs_out_desc);
	if (!ep)
		goto fail;
	gser->port.out = ep;
	ep->driver_data = cdev;	/* claim */

	/* copy descriptors, and track endpoint copies */
	f->descriptors = usb_copy_descriptors(gser_fs_function);

	gser->fs.in = usb_find_endpoint(gser_fs_function,
			f->descriptors, &gser_fs_in_desc);
	gser->fs.out = usb_find_endpoint(gser_fs_function,
			f->descriptors, &gser_fs_out_desc);


	/* support all relevant hardware speeds... we expect that when
	 * hardware is dual speed, all bulk-capable endpoints work at
	 * both speeds
	 */
	if (gadget_is_dualspeed(c->cdev->gadget)) {
		gser_hs_in_desc.bEndpointAddress =
				gser_fs_in_desc.bEndpointAddress;
		gser_hs_out_desc.bEndpointAddress =
				gser_fs_out_desc.bEndpointAddress;

		/* copy descriptors, and track endpoint copies */
		f->hs_descriptors = usb_copy_descriptors(gser_hs_function);

		gser->hs.in = usb_find_endpoint(gser_hs_function,
				f->hs_descriptors, &gser_hs_in_desc);
		gser->hs.out = usb_find_endpoint(gser_hs_function,
				f->hs_descriptors, &gser_hs_out_desc);
	}

	DBG(cdev, "generic ttyGS%d: %s speed IN/%s OUT/%s\n",
			gser->port_num,
			gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
			gser->port.in->name, gser->port.out->name);
	return 0;

fail:
	/* we might as well release our claims on endpoints */
	if (gser->port.out)
		gser->port.out->driver_data = NULL;
	if (gser->port.in)
		gser->port.in->driver_data = NULL;

	ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);

	return status;
}

static void
gser_unbind(struct usb_configuration *c, struct usb_function *f)
{
	if (gadget_is_dualspeed(c->cdev->gadget))
		usb_free_descriptors(f->hs_descriptors);
	usb_free_descriptors(f->descriptors);
	kfree(func_to_gser(f));
}

/**
 * gser_bind_config - add a generic serial function to a configuration
 * @c: the configuration to support the serial instance
 * @port_num: /dev/ttyGS* port this interface will use
 * Context: single threaded during gadget setup
 *
 * Returns zero on success, else negative errno.
 *
 * Caller must have called @gserial_setup() with enough ports to
 * handle all the ones it binds.  Caller is also responsible
 * for calling @gserial_cleanup() before module unload.
 */
int __init gser_bind_config(struct usb_configuration *c, u8 port_num)
{
	struct f_gser	*gser;
	int		status;

	/* REVISIT might want instance-specific strings to help
	 * distinguish instances ...
	 */

	/* maybe allocate device-global string ID */
	if (gser_string_defs[0].id == 0) {
		status = usb_string_id(c->cdev);
		if (status < 0)
			return status;
		gser_string_defs[0].id = status;
	}

	/* allocate and initialize one new instance */
	gser = kzalloc(sizeof *gser, GFP_KERNEL);
	if (!gser)
		return -ENOMEM;

	gser->port_num = port_num;

	gser->port.func.name = "gser";
	gser->port.func.strings = gser_strings;
	gser->port.func.bind = gser_bind;
	gser->port.func.unbind = gser_unbind;
	gser->port.func.set_alt = gser_set_alt;
	gser->port.func.disable = gser_disable;

	status = usb_add_function(c, &gser->port.func);
	if (status)
		kfree(gser);
	return status;
}
Commit	Line	Data
61d8baea DB	1	/*
	2	* f_serial.c - generic USB serial function driver
	3	*
	4	* Copyright (C) 2003 Al Borchers (alborchers@steinerpoint.com)
	5	* Copyright (C) 2008 by David Brownell
	6	* Copyright (C) 2008 by Nokia Corporation
	7	*
	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.
	11	*/
	12
5a0e3ad6	13	#include <linux/slab.h>
61d8baea DB	14	#include <linux/kernel.h>
	15	#include <linux/device.h>
	16
	17	#include "u_serial.h"
	18	#include "gadget_chips.h"
	19
	20
	21	/*
	22	* This function packages a simple "generic serial" port with no real
	23	* control mechanisms, just raw data transfer over two bulk endpoints.
	24	*
	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.
	28	*/
	29
	30	struct gser_descs {
	31	struct usb_endpoint_descriptor *in;
	32	struct usb_endpoint_descriptor *out;
	33	};
	34
	35	struct f_gser {
	36	struct gserial port;
	37	u8 data_id;
	38	u8 port_num;
	39
61d8baea	40	struct gser_descs fs;
61d8baea DB	41	struct gser_descs hs;
	42	};
	43
	44	static inline struct f_gser func_to_gser(struct usb_function f)
	45	{
	46	return container_of(f, struct f_gser, port.func);
	47	}
	48
	49	/-------------------------------------------------------------------------/
	50
	51	/* interface descriptor: */
	52
	53	static struct usb_interface_descriptor gser_interface_desc __initdata = {
	54	.bLength = USB_DT_INTERFACE_SIZE,
	55	.bDescriptorType = USB_DT_INTERFACE,
	56	/* .bInterfaceNumber = DYNAMIC */
	57	.bNumEndpoints = 2,
	58	.bInterfaceClass = USB_CLASS_VENDOR_SPEC,
	59	.bInterfaceSubClass = 0,
	60	.bInterfaceProtocol = 0,
	61	/* .iInterface = DYNAMIC */
	62	};
	63
	64	/* full speed support: */
	65
	66	static struct usb_endpoint_descriptor gser_fs_in_desc __initdata = {
	67	.bLength = USB_DT_ENDPOINT_SIZE,
	68	.bDescriptorType = USB_DT_ENDPOINT,
	69	.bEndpointAddress = USB_DIR_IN,
	70	.bmAttributes = USB_ENDPOINT_XFER_BULK,
	71	};
	72
	73	static struct usb_endpoint_descriptor gser_fs_out_desc __initdata = {
	74	.bLength = USB_DT_ENDPOINT_SIZE,
	75	.bDescriptorType = USB_DT_ENDPOINT,
	76	.bEndpointAddress = USB_DIR_OUT,
	77	.bmAttributes = USB_ENDPOINT_XFER_BULK,
	78	};
	79
	80	static struct usb_descriptor_header *gser_fs_function[] __initdata = {
	81	(struct usb_descriptor_header *) &gser_interface_desc,
	82	(struct usb_descriptor_header *) &gser_fs_in_desc,
	83	(struct usb_descriptor_header *) &gser_fs_out_desc,
	84	NULL,
	85	};
	86
	87	/* high speed support: */
	88
	89	static struct usb_endpoint_descriptor gser_hs_in_desc __initdata = {
	90	.bLength = USB_DT_ENDPOINT_SIZE,
	91	.bDescriptorType = USB_DT_ENDPOINT,
	92	.bmAttributes = USB_ENDPOINT_XFER_BULK,
551509d2	93	.wMaxPacketSize = cpu_to_le16(512),
61d8baea DB	94	};
	95
	96	static struct usb_endpoint_descriptor gser_hs_out_desc __initdata = {
	97	.bLength = USB_DT_ENDPOINT_SIZE,
	98	.bDescriptorType = USB_DT_ENDPOINT,
	99	.bmAttributes = USB_ENDPOINT_XFER_BULK,
551509d2	100	.wMaxPacketSize = cpu_to_le16(512),
61d8baea DB	101	};
	102
	103	static struct usb_descriptor_header *gser_hs_function[] __initdata = {
	104	(struct usb_descriptor_header *) &gser_interface_desc,
	105	(struct usb_descriptor_header *) &gser_hs_in_desc,
	106	(struct usb_descriptor_header *) &gser_hs_out_desc,
	107	NULL,
	108	};
	109
	110	/* string descriptors: */
	111
	112	static struct usb_string gser_string_defs[] = {
	113	[0].s = "Generic Serial",
	114	{ } /* end of list */
	115	};
	116
	117	static struct usb_gadget_strings gser_string_table = {
	118	.language = 0x0409, /* en-us */
	119	.strings = gser_string_defs,
	120	};
	121
	122	static struct usb_gadget_strings *gser_strings[] = {
	123	&gser_string_table,
	124	NULL,
	125	};
	126
	127	/-------------------------------------------------------------------------/
	128
	129	static int gser_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
	130	{
	131	struct f_gser *gser = func_to_gser(f);
	132	struct usb_composite_dev *cdev = f->config->cdev;
	133
	134	/* we know alt == 0, so this is an activation or a reset */
	135
	136	if (gser->port.in->driver_data) {
	137	DBG(cdev, "reset generic ttyGS%d\n", gser->port_num);
	138	gserial_disconnect(&gser->port);
	139	} else {
	140	DBG(cdev, "activate generic ttyGS%d\n", gser->port_num);
	141	gser->port.in_desc = ep_choose(cdev->gadget,
	142	gser->hs.in, gser->fs.in);
	143	gser->port.out_desc = ep_choose(cdev->gadget,
	144	gser->hs.out, gser->fs.out);
	145	}
	146	gserial_connect(&gser->port, gser->port_num);
	147	return 0;
	148	}
	149
	150	static void gser_disable(struct usb_function *f)
	151	{
	152	struct f_gser *gser = func_to_gser(f);
	153	struct usb_composite_dev *cdev = f->config->cdev;
	154
	155	DBG(cdev, "generic ttyGS%d deactivated\n", gser->port_num);
	156	gserial_disconnect(&gser->port);
	157	}
	158
	159	/-------------------------------------------------------------------------/
	160
	161	/* serial function driver setup/binding */
	162
	163	static int __init
	164	gser_bind(struct usb_configuration c, struct usb_function f)
165	{
166	struct usb_composite_dev *cdev = c->cdev;
167	struct f_gser *gser = func_to_gser(f);
168	int status;
169	struct usb_ep *ep;
170
171	/* allocate instance-specific interface IDs */
172	status = usb_interface_id(c, f);
173	if (status < 0)
174	goto fail;
175	gser->data_id = status;
176	gser_interface_desc.bInterfaceNumber = status;
177
178	status = -ENODEV;
179
180	/* allocate instance-specific endpoints */
181	ep = usb_ep_autoconfig(cdev->gadget, &gser_fs_in_desc);
182	if (!ep)
183	goto fail;
184	gser->port.in = ep;
185	ep->driver_data = cdev; /* claim */
186
187	ep = usb_ep_autoconfig(cdev->gadget, &gser_fs_out_desc);
188	if (!ep)
189	goto fail;
190	gser->port.out = ep;
191	ep->driver_data = cdev; /* claim */
192
193	/* copy descriptors, and track endpoint copies */
194	f->descriptors = usb_copy_descriptors(gser_fs_function);
195
196	gser->fs.in = usb_find_endpoint(gser_fs_function,
197	f->descriptors, &gser_fs_in_desc);
198	gser->fs.out = usb_find_endpoint(gser_fs_function,
199	f->descriptors, &gser_fs_out_desc);
200
201
202	/* support all relevant hardware speeds... we expect that when
203	* hardware is dual speed, all bulk-capable endpoints work at
204	* both speeds
205	*/
206	if (gadget_is_dualspeed(c->cdev->gadget)) {
207	gser_hs_in_desc.bEndpointAddress =
208	gser_fs_in_desc.bEndpointAddress;
209	gser_hs_out_desc.bEndpointAddress =
210	gser_fs_out_desc.bEndpointAddress;
211
212	/* copy descriptors, and track endpoint copies */
213	f->hs_descriptors = usb_copy_descriptors(gser_hs_function);
214
215	gser->hs.in = usb_find_endpoint(gser_hs_function,
216	f->hs_descriptors, &gser_hs_in_desc);
217	gser->hs.out = usb_find_endpoint(gser_hs_function,
218	f->hs_descriptors, &gser_hs_out_desc);
219	}
220
221	DBG(cdev, "generic ttyGS%d: %s speed IN/%s OUT/%s\n",
222	gser->port_num,
223	gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
224	gser->port.in->name, gser->port.out->name);
225	return 0;
226
227	fail:
228	/* we might as well release our claims on endpoints */
229	if (gser->port.out)
230	gser->port.out->driver_data = NULL;
231	if (gser->port.in)
232	gser->port.in->driver_data = NULL;
233
234	ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
235
236	return status;
237	}
238
239	static void
240	gser_unbind(struct usb_configuration c, struct usb_function f)
241	{
242	if (gadget_is_dualspeed(c->cdev->gadget))
243	usb_free_descriptors(f->hs_descriptors);
244	usb_free_descriptors(f->descriptors);
245	kfree(func_to_gser(f));
246	}
247
248	/**
249	* gser_bind_config - add a generic serial function to a configuration
250	* @c: the configuration to support the serial instance
251	* @port_num: /dev/ttyGS* port this interface will use
252	* Context: single threaded during gadget setup
253	*
254	* Returns zero on success, else negative errno.
255	*
256	* Caller must have called @gserial_setup() with enough ports to
257	* handle all the ones it binds. Caller is also responsible
258	* for calling @gserial_cleanup() before module unload.
259	*/
260	int __init gser_bind_config(struct usb_configuration *c, u8 port_num)
261	{
262	struct f_gser *gser;
263	int status;
264
265	/* REVISIT might want instance-specific strings to help
266	* distinguish instances ...
267	*/
268
269	/* maybe allocate device-global string ID */
270	if (gser_string_defs[0].id == 0) {
271	status = usb_string_id(c->cdev);
272	if (status < 0)
273	return status;
274	gser_string_defs[0].id = status;
275	}
276
277	/* allocate and initialize one new instance */
278	gser = kzalloc(sizeof *gser, GFP_KERNEL);
279	if (!gser)
280	return -ENOMEM;
281
282	gser->port_num = port_num;
283
284	gser->port.func.name = "gser";
285	gser->port.func.strings = gser_strings;
286	gser->port.func.bind = gser_bind;
287	gser->port.func.unbind = gser_unbind;
288	gser->port.func.set_alt = gser_set_alt;
289	gser->port.func.disable = gser_disable;
290
291	status = usb_add_function(c, &gser->port.func);
292	if (status)
293	kfree(gser);
294	return status;
295	}