/*
 * include/media/i2c/as3645a.h
 *
 * Copyright (C) 2008-2011 Nokia Corporation
 *
 * Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 *
 */

#ifndef __AS3645A_H__
#define __AS3645A_H__

#include <media/v4l2-subdev.h>

#define AS3645A_NAME				"as3645a"
#define AS3645A_I2C_ADDR			(0x60 >> 1) /* W:0x60, R:0x61 */

#define AS3645A_FLASH_TIMEOUT_MIN		100000	/* us */
#define AS3645A_FLASH_TIMEOUT_MAX		850000
#define AS3645A_FLASH_TIMEOUT_STEP		50000

#define AS3645A_FLASH_INTENSITY_MIN		200	/* mA */
#define AS3645A_FLASH_INTENSITY_MAX_1LED	500
#define AS3645A_FLASH_INTENSITY_MAX_2LEDS	400
#define AS3645A_FLASH_INTENSITY_STEP		20

#define AS3645A_TORCH_INTENSITY_MIN		20	/* mA */
#define AS3645A_TORCH_INTENSITY_MAX		160
#define AS3645A_TORCH_INTENSITY_STEP		20

#define AS3645A_INDICATOR_INTENSITY_MIN		0	/* uA */
#define AS3645A_INDICATOR_INTENSITY_MAX		10000
#define AS3645A_INDICATOR_INTENSITY_STEP	2500

/*
 * as3645a_platform_data - Flash controller platform data
 * @set_power:	Set power callback
 * @vref:	VREF offset (0=0V, 1=+0.3V, 2=-0.3V, 3=+0.6V)
 * @peak:	Inductor peak current limit (0=1.25A, 1=1.5A, 2=1.75A, 3=2.0A)
 * @ext_strobe:	True if external flash strobe can be used
 * @flash_max_current:	Max flash current (mA, <= AS3645A_FLASH_INTENSITY_MAX)
 * @torch_max_current:	Max torch current (mA, >= AS3645A_TORCH_INTENSITY_MAX)
 * @timeout_max:	Max flash timeout (us, <= AS3645A_FLASH_TIMEOUT_MAX)
 */
struct as3645a_platform_data {
	int (*set_power)(struct v4l2_subdev *subdev, int on);
	unsigned int vref;
	unsigned int peak;
	bool ext_strobe;

	/* Flash and torch currents and timeout limits */
	unsigned int flash_max_current;
	unsigned int torch_max_current;
	unsigned int timeout_max;
};

#endif /* __AS3645A_H__ */
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<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/commit/?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>root</a>/<a href='/cgit.cgi/linux/net-next.git/commit/net?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>net</a>/<a href='/cgit.cgi/linux/net-next.git/commit/net/netlabel?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>netlabel</a>/<a href='/cgit.cgi/linux/net-next.git/commit/net/netlabel/netlabel_addrlist.c?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>netlabel_addrlist.c</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='id' value='39cb2c9a316e77f6dfba96c543e55b6672d5a37e'/><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>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2017-01-29 13:50:06 -0800</td></tr>
<tr><th>committer</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2017-01-29 13:50:06 -0800</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/netlabel/netlabel_addrlist.c?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>39cb2c9a316e77f6dfba96c543e55b6672d5a37e</a> (<a href='/cgit.cgi/linux/net-next.git/patch/net/netlabel/netlabel_addrlist.c?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>98fe974ee4e20121253de7f61fc8d01bdb3821c1</a> /<a href='/cgit.cgi/linux/net-next.git/tree/net/netlabel/netlabel_addrlist.c?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>net/netlabel/netlabel_addrlist.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/netlabel/netlabel_addrlist.c?id=2c5d9555d6d937966d79d4c6529a5f7b9206e405'>2c5d9555d6d937966d79d4c6529a5f7b9206e405</a> (<a href='/cgit.cgi/linux/net-next.git/diff/net/netlabel/netlabel_addrlist.c?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e&amp;id2=2c5d9555d6d937966d79d4c6529a5f7b9206e405'>diff</a>)</td></tr></table>
<div class='commit-subject'>drm/i915: Check for NULL i915_vma in intel_unpin_fb_obj()</div><div class='commit-msg'>I've seen this trigger twice now, where the i915_gem_object_to_ggtt()
call in intel_unpin_fb_obj() returns NULL, resulting in an oops
immediately afterwards as the (inlined) call to i915_vma_unpin_fence()
tries to dereference it.

It seems to be some race condition where the object is going away at
shutdown time, since both times happened when shutting down the X
server.  The call chains were different:

 - VT ioctl(KDSETMODE, KD_TEXT):

    intel_cleanup_plane_fb+0x5b/0xa0 [i915]
    drm_atomic_helper_cleanup_planes+0x6f/0x90 [drm_kms_helper]
    intel_atomic_commit_tail+0x749/0xfe0 [i915]
    intel_atomic_commit+0x3cb/0x4f0 [i915]
    drm_atomic_commit+0x4b/0x50 [drm]
    restore_fbdev_mode+0x14c/0x2a0 [drm_kms_helper]
    drm_fb_helper_restore_fbdev_mode_unlocked+0x34/0x80 [drm_kms_helper]
    drm_fb_helper_set_par+0x2d/0x60 [drm_kms_helper]
    intel_fbdev_set_par+0x18/0x70 [i915]
    fb_set_var+0x236/0x460
    fbcon_blank+0x30f/0x350
    do_unblank_screen+0xd2/0x1a0
    vt_ioctl+0x507/0x12a0
    tty_ioctl+0x355/0xc30
    do_vfs_ioctl+0xa3/0x5e0
    SyS_ioctl+0x79/0x90
    entry_SYSCALL_64_fastpath+0x13/0x94

 - i915 unpin_work workqueue:

    intel_unpin_work_fn+0x58/0x140 [i915]
    process_one_work+0x1f1/0x480
    worker_thread+0x48/0x4d0
    kthread+0x101/0x140

and this patch purely papers over the issue by adding a NULL pointer
check and a WARN_ON_ONCE() to avoid the oops that would then generally
make the machine unresponsive.

Other callers of i915_gem_object_to_ggtt() seem to also check for the
returned pointer being NULL and warn about it, so this clearly has
happened before in other places.

[ Reported it originally to the i915 developers on Jan 8, applying the
  ugly workaround on my own now after triggering the problem for the
  second time with no feedback.

  This is likely to be the same bug reported as

     https://bugs.freedesktop.org/show_bug.cgi?id=98829
     https://bugs.freedesktop.org/show_bug.cgi?id=99134

  which has a patch for the underlying problem, but it hasn't gotten to
  me, so I'm applying the workaround. ]

Cc: Daniel Vetter &lt;daniel.vetter@intel.com&gt;
Cc: Jani Nikula &lt;jani.nikula@linux.intel.com&gt;
Cc: Ville Syrjälä &lt;ville.syrjala@linux.intel.com&gt;
Cc: Chris Wilson &lt;chris@chris-wilson.co.uk&gt;
Cc: Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt;
Cc: Tvrtko Ursulin &lt;tvrtko.ursulin@intel.com&gt;
Cc: Imre Deak &lt;imre.deak@intel.com&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/?id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>Diffstat</a> (limited to 'net/netlabel/netlabel_addrlist.c')</div><table summary='diffstat' class='diffstat'>