/*
 * u_serial.h - interface to USB gadget "serial port"/TTY utilities
 *
 * Copyright (C) 2008 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.
 */

#ifndef __U_SERIAL_H
#define __U_SERIAL_H

#include <linux/usb/composite.h>
#include <linux/usb/cdc.h>

#define MAX_U_SERIAL_PORTS	4

struct f_serial_opts {
	struct usb_function_instance func_inst;
	u8 port_num;
};

/*
 * One non-multiplexed "serial" I/O port ... there can be several of these
 * on any given USB peripheral device, if it provides enough endpoints.
 *
 * The "u_serial" utility component exists to do one thing:  manage TTY
 * style I/O using the USB peripheral endpoints listed here, including
 * hookups to sysfs and /dev for each logical "tty" device.
 *
 * REVISIT at least ACM could support tiocmget() if needed.
 *
 * REVISIT someday, allow multiplexing several TTYs over these endpoints.
 */
struct gserial {
	struct usb_function		func;

	/* port is managed by gserial_{connect,disconnect} */
	struct gs_port			*ioport;

	struct usb_ep			*in;
	struct usb_ep			*out;

	/* REVISIT avoid this CDC-ACM support harder ... */
	struct usb_cdc_line_coding port_line_coding;	/* 9600-8-N-1 etc */

	/* notification callbacks */
	void (*connect)(struct gserial *p);
	void (*disconnect)(struct gserial *p);
	int (*send_break)(struct gserial *p, int duration);
};

/* utilities to allocate/free request and buffer */
struct usb_request *gs_alloc_req(struct usb_ep *ep, unsigned len, gfp_t flags);
void gs_free_req(struct usb_ep *, struct usb_request *req);

/* management of individual TTY ports */
int gserial_alloc_line(unsigned char *port_line);
void gserial_free_line(unsigned char port_line);

/* connect/disconnect is handled by individual functions */
int gserial_connect(struct gserial *, u8 port_num);
void gserial_disconnect(struct gserial *);

/* functions are bound to configurations by a config or gadget driver */
int gser_bind_config(struct usb_configuration *c, u8 port_num);
int obex_bind_config(struct usb_configuration *c, u8 port_num);

#endif /* __U_SERIAL_H */
emove&amp;id=f598f82e204ec0b17797caaf1b0311c52d43fb9a'>diff</a></td><td class='form'><form class='right' method='get' action='/cgit.cgi/linux/net-next.git/log/include/trace/events/skb.h'>
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<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/commit/?h=nds-private-remove&amp;id=f598f82e204ec0b17797caaf1b0311c52d43fb9a'>root</a>/<a href='/cgit.cgi/linux/net-next.git/commit/include?h=nds-private-remove&amp;id=f598f82e204ec0b17797caaf1b0311c52d43fb9a'>include</a>/<a href='/cgit.cgi/linux/net-next.git/commit/include/trace?h=nds-private-remove&amp;id=f598f82e204ec0b17797caaf1b0311c52d43fb9a'>trace</a>/<a href='/cgit.cgi/linux/net-next.git/commit/include/trace/events?h=nds-private-remove&amp;id=f598f82e204ec0b17797caaf1b0311c52d43fb9a'>events</a>/<a href='/cgit.cgi/linux/net-next.git/commit/include/trace/events/skb.h?h=nds-private-remove&amp;id=f598f82e204ec0b17797caaf1b0311c52d43fb9a'>skb.h</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='h' value='nds-private-remove'/><input type='hidden' name='id' value='f598f82e204ec0b17797caaf1b0311c52d43fb9a'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Coly Li &lt;colyli@suse.de&gt;</td><td class='right'>2017-01-24 15:18:46 -0800</td></tr>
<tr><th>committer</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2017-01-24 16:26:14 -0800</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/include/trace/events/skb.h?h=nds-private-remove&amp;id=f598f82e204ec0b17797caaf1b0311c52d43fb9a'>f598f82e204ec0b17797caaf1b0311c52d43fb9a</a> (<a href='/cgit.cgi/linux/net-next.git/patch/include/trace/events/skb.h?id=f598f82e204ec0b17797caaf1b0311c52d43fb9a'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?h=nds-private-remove&amp;id=f598f82e204ec0b17797caaf1b0311c52d43fb9a'>20e0109db50c168a36df14af76b484eaf9b71836</a> /<a href='/cgit.cgi/linux/net-next.git/tree/include/trace/events/skb.h?h=nds-private-remove&amp;id=f598f82e204ec0b17797caaf1b0311c52d43fb9a'>include/trace/events/skb.h</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/include/trace/events/skb.h?h=nds-private-remove&amp;id=4180c4c170a5a33b9987b314d248a9d572d89ab0'>4180c4c170a5a33b9987b314d248a9d572d89ab0</a> (<a href='/cgit.cgi/linux/net-next.git/diff/include/trace/events/skb.h?h=nds-private-remove&amp;id=f598f82e204ec0b17797caaf1b0311c52d43fb9a&amp;id2=4180c4c170a5a33b9987b314d248a9d572d89ab0'>diff</a>)</td></tr></table>
<div class='commit-subject'>romfs: use different way to generate fsid for BLOCK or MTD</div><div class='commit-msg'>Commit 8a59f5d25265 ("fs/romfs: return f_fsid for statfs(2)") generates
a 64bit id from sb-&gt;s_bdev-&gt;bd_dev.  This is only correct when romfs is
defined with CONFIG_ROMFS_ON_BLOCK.  If romfs is only defined with
CONFIG_ROMFS_ON_MTD, sb-&gt;s_bdev is NULL, referencing sb-&gt;s_bdev-&gt;bd_dev
will triger an oops.

Richard Weinberger points out that when CONFIG_ROMFS_BACKED_BY_BOTH=y,
both CONFIG_ROMFS_ON_BLOCK and CONFIG_ROMFS_ON_MTD are defined.
Therefore when calling huge_encode_dev() to generate a 64bit id, I use
the follow order to choose parameter,

- CONFIG_ROMFS_ON_BLOCK defined
  use sb-&gt;s_bdev-&gt;bd_dev
- CONFIG_ROMFS_ON_BLOCK undefined and CONFIG_ROMFS_ON_MTD defined
  use sb-&gt;s_dev when,
- both CONFIG_ROMFS_ON_BLOCK and CONFIG_ROMFS_ON_MTD undefined
  leave id as 0

When CONFIG_ROMFS_ON_MTD is defined and sb-&gt;s_mtd is not NULL, sb-&gt;s_dev
is set to a device ID generated by MTD_BLOCK_MAJOR and mtd index,
otherwise sb-&gt;s_dev is 0.

This is a try-best effort to generate a uniq file system ID, if all the
above conditions are not meet, f_fsid of this romfs instance will be 0.
Generally only one romfs can be built on single MTD block device, this
method is enough to identify multiple romfs instances in a computer.

Link: http://lkml.kernel.org/r/1482928596-115155-1-git-send-email-colyli@suse.de
Signed-off-by: Coly Li &lt;colyli@suse.de&gt;
Reported-by: Nong Li &lt;nongli1031@gmail.com&gt;
Tested-by: Nong Li &lt;nongli1031@gmail.com&gt;
Cc: Richard Weinberger &lt;richard.weinberger@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=f598f82e204ec0b17797caaf1b0311c52d43fb9a'>Diffstat</a> (limited to 'include/trace/events/skb.h')</div><table summary='diffstat' class='diffstat'>