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-rw-r--r--Documentation/ABI/testing/debugfs-pktcdvd5
-rw-r--r--Documentation/ABI/testing/sysfs-class-pktcdvd2
-rw-r--r--Documentation/DocBook/gadget.tmpl4
-rw-r--r--Documentation/DocBook/kernel-api.tmpl3
-rw-r--r--Documentation/DocBook/stylesheet.xsl1
-rw-r--r--Documentation/DocBook/usb.tmpl6
-rw-r--r--Documentation/HOWTO1
-rw-r--r--Documentation/auxdisplay/cfag12864b105
-rw-r--r--Documentation/auxdisplay/cfag12864b-example.c282
-rw-r--r--Documentation/auxdisplay/ks010855
-rw-r--r--Documentation/cdrom/packet-writing.txt2
-rw-r--r--Documentation/crypto/api-intro.txt4
-rw-r--r--Documentation/driver-model/devres.txt268
-rw-r--r--Documentation/drivers/edac/edac.txt16
-rw-r--r--Documentation/fb/s3fb.txt78
-rw-r--r--Documentation/feature-removal-schedule.txt67
-rw-r--r--Documentation/filesystems/relay.txt9
-rw-r--r--Documentation/filesystems/ufs.txt9
-rw-r--r--Documentation/gpio.txt271
-rw-r--r--Documentation/ioctl-number.txt3
-rw-r--r--Documentation/isdn/README.gigaset65
-rw-r--r--Documentation/kdump/kdump.txt8
-rw-r--r--Documentation/kernel-doc-nano-HOWTO.txt39
-rw-r--r--Documentation/kernel-parameters.txt2
-rw-r--r--Documentation/local_ops.txt163
-rw-r--r--Documentation/nfsroot.txt4
-rw-r--r--Documentation/rbtree.txt192
-rw-r--r--Documentation/rtc.txt46
-rw-r--r--Documentation/s390/Debugging390.txt2
-rw-r--r--Documentation/scsi/ChangeLog.megaraid16
-rw-r--r--Documentation/sound/alsa/ALSA-Configuration.txt60
-rw-r--r--Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl4
-rw-r--r--Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl33
-rw-r--r--Documentation/sound/alsa/hda_codec.txt10
-rw-r--r--Documentation/sound/alsa/soc/DAI.txt56
-rw-r--r--Documentation/sound/alsa/soc/clocking.txt51
-rw-r--r--Documentation/sound/alsa/soc/codec.txt197
-rw-r--r--Documentation/sound/alsa/soc/dapm.txt297
-rw-r--r--Documentation/sound/alsa/soc/machine.txt113
-rw-r--r--Documentation/sound/alsa/soc/overview.txt83
-rw-r--r--Documentation/sound/alsa/soc/platform.txt58
-rw-r--r--Documentation/sound/alsa/soc/pops_clicks.txt52
-rw-r--r--Documentation/spi/spi-summary3
-rw-r--r--Documentation/sysrq.txt44
-rw-r--r--Documentation/usb/proc_usb_info.txt21
-rw-r--r--Documentation/usb/usbmon.txt152
-rw-r--r--Documentation/video-output.txt34
47 files changed, 2838 insertions, 158 deletions
diff --git a/Documentation/ABI/testing/debugfs-pktcdvd b/Documentation/ABI/testing/debugfs-pktcdvd
index 03dbd883cc4..bf9c16b64c3 100644
--- a/Documentation/ABI/testing/debugfs-pktcdvd
+++ b/Documentation/ABI/testing/debugfs-pktcdvd
@@ -1,6 +1,6 @@
What: /debug/pktcdvd/pktcdvd[0-7]
Date: Oct. 2006
-KernelVersion: 2.6.19
+KernelVersion: 2.6.20
Contact: Thomas Maier <balagi@justmail.de>
Description:
@@ -11,8 +11,7 @@ The pktcdvd module (packet writing driver) creates
these files in debugfs:
/debug/pktcdvd/pktcdvd[0-7]/
- info (0444) Lots of human readable driver
- statistics and infos. Multiple lines!
+ info (0444) Lots of driver statistics and infos.
Example:
-------
diff --git a/Documentation/ABI/testing/sysfs-class-pktcdvd b/Documentation/ABI/testing/sysfs-class-pktcdvd
index c4c55edc9a5..b1c3f026335 100644
--- a/Documentation/ABI/testing/sysfs-class-pktcdvd
+++ b/Documentation/ABI/testing/sysfs-class-pktcdvd
@@ -1,6 +1,6 @@
What: /sys/class/pktcdvd/
Date: Oct. 2006
-KernelVersion: 2.6.19
+KernelVersion: 2.6.20
Contact: Thomas Maier <balagi@justmail.de>
Description:
diff --git a/Documentation/DocBook/gadget.tmpl b/Documentation/DocBook/gadget.tmpl
index a3444243612..e7fc9643340 100644
--- a/Documentation/DocBook/gadget.tmpl
+++ b/Documentation/DocBook/gadget.tmpl
@@ -482,13 +482,13 @@ slightly.
<para>Gadget drivers
rely on common USB structures and constants
defined in the
-<filename>&lt;linux/usb_ch9.h&gt;</filename>
+<filename>&lt;linux/usb/ch9.h&gt;</filename>
header file, which is standard in Linux 2.6 kernels.
These are the same types and constants used by host
side drivers (and usbcore).
</para>
-!Iinclude/linux/usb_ch9.h
+!Iinclude/linux/usb/ch9.h
</sect1>
<sect1 id="core"><title>Core Objects and Methods</title>
diff --git a/Documentation/DocBook/kernel-api.tmpl b/Documentation/DocBook/kernel-api.tmpl
index 3fa0c4b4541..0bb90237e23 100644
--- a/Documentation/DocBook/kernel-api.tmpl
+++ b/Documentation/DocBook/kernel-api.tmpl
@@ -316,6 +316,9 @@ X!Earch/i386/kernel/mca.c
<sect1><title>DMI Interfaces</title>
!Edrivers/firmware/dmi_scan.c
</sect1>
+ <sect1><title>EDD Interfaces</title>
+!Idrivers/firmware/edd.c
+ </sect1>
</chapter>
<chapter id="security">
diff --git a/Documentation/DocBook/stylesheet.xsl b/Documentation/DocBook/stylesheet.xsl
index 3ccce886c34..974e17ccf10 100644
--- a/Documentation/DocBook/stylesheet.xsl
+++ b/Documentation/DocBook/stylesheet.xsl
@@ -4,4 +4,5 @@
<param name="funcsynopsis.style">ansi</param>
<param name="funcsynopsis.tabular.threshold">80</param>
<!-- <param name="paper.type">A4</param> -->
+<param name="generate.section.toc.level">2</param>
</stylesheet>
diff --git a/Documentation/DocBook/usb.tmpl b/Documentation/DocBook/usb.tmpl
index 143e5ff7deb..a2ebd651b05 100644
--- a/Documentation/DocBook/usb.tmpl
+++ b/Documentation/DocBook/usb.tmpl
@@ -187,13 +187,13 @@
<chapter><title>USB-Standard Types</title>
- <para>In <filename>&lt;linux/usb_ch9.h&gt;</filename> you will find
+ <para>In <filename>&lt;linux/usb/ch9.h&gt;</filename> you will find
the USB data types defined in chapter 9 of the USB specification.
These data types are used throughout USB, and in APIs including
this host side API, gadget APIs, and usbfs.
</para>
-!Iinclude/linux/usb_ch9.h
+!Iinclude/linux/usb/ch9.h
</chapter>
@@ -574,7 +574,7 @@ for (;;) {
#include &lt;asm/byteorder.h&gt;</programlisting>
The standard USB device model requests, from "Chapter 9" of
the USB 2.0 specification, are automatically included from
- the <filename>&lt;linux/usb_ch9.h&gt;</filename> header.
+ the <filename>&lt;linux/usb/ch9.h&gt;</filename> header.
</para>
<para>Unless noted otherwise, the ioctl requests
diff --git a/Documentation/HOWTO b/Documentation/HOWTO
index 8d51c148f72..48123dba5e6 100644
--- a/Documentation/HOWTO
+++ b/Documentation/HOWTO
@@ -30,6 +30,7 @@ are not a good substitute for a solid C education and/or years of
experience, the following books are good for, if anything, reference:
- "The C Programming Language" by Kernighan and Ritchie [Prentice Hall]
- "Practical C Programming" by Steve Oualline [O'Reilly]
+ - "C: A Reference Manual" by Harbison and Steele [Prentice Hall]
The kernel is written using GNU C and the GNU toolchain. While it
adheres to the ISO C89 standard, it uses a number of extensions that are
diff --git a/Documentation/auxdisplay/cfag12864b b/Documentation/auxdisplay/cfag12864b
new file mode 100644
index 00000000000..3572b98f45b
--- /dev/null
+++ b/Documentation/auxdisplay/cfag12864b
@@ -0,0 +1,105 @@
+ ===================================
+ cfag12864b LCD Driver Documentation
+ ===================================
+
+License: GPLv2
+Author & Maintainer: Miguel Ojeda Sandonis <maxextreme@gmail.com>
+Date: 2006-10-27
+
+
+
+--------
+0. INDEX
+--------
+
+ 1. DRIVER INFORMATION
+ 2. DEVICE INFORMATION
+ 3. WIRING
+ 4. USERSPACE PROGRAMMING
+
+
+---------------------
+1. DRIVER INFORMATION
+---------------------
+
+This driver support one cfag12864b display at time.
+
+
+---------------------
+2. DEVICE INFORMATION
+---------------------
+
+Manufacturer: Crystalfontz
+Device Name: Crystalfontz 12864b LCD Series
+Device Code: cfag12864b
+Webpage: http://www.crystalfontz.com
+Device Webpage: http://www.crystalfontz.com/products/12864b/
+Type: LCD (Liquid Crystal Display)
+Width: 128
+Height: 64
+Colors: 2 (B/N)
+Controller: ks0108
+Controllers: 2
+Pages: 8 each controller
+Addresses: 64 each page
+Data size: 1 byte each address
+Memory size: 2 * 8 * 64 * 1 = 1024 bytes = 1 Kbyte
+
+
+---------
+3. WIRING
+---------
+
+The cfag12864b LCD Series don't have official wiring.
+
+The common wiring is done to the parallel port as shown:
+
+Parallel Port cfag12864b
+
+ Name Pin# Pin# Name
+
+Strobe ( 1)------------------------------(17) Enable
+Data 0 ( 2)------------------------------( 4) Data 0
+Data 1 ( 3)------------------------------( 5) Data 1
+Data 2 ( 4)------------------------------( 6) Data 2
+Data 3 ( 5)------------------------------( 7) Data 3
+Data 4 ( 6)------------------------------( 8) Data 4
+Data 5 ( 7)------------------------------( 9) Data 5
+Data 6 ( 8)------------------------------(10) Data 6
+Data 7 ( 9)------------------------------(11) Data 7
+ (10) [+5v]---( 1) Vdd
+ (11) [GND]---( 2) Ground
+ (12) [+5v]---(14) Reset
+ (13) [GND]---(15) Read / Write
+ Line (14)------------------------------(13) Controller Select 1
+ (15)
+ Init (16)------------------------------(12) Controller Select 2
+Select (17)------------------------------(16) Data / Instruction
+Ground (18)---[GND] [+5v]---(19) LED +
+Ground (19)---[GND]
+Ground (20)---[GND] E A Values:
+Ground (21)---[GND] [GND]---[P1]---(18) Vee · R = Resistor = 22 ohm
+Ground (22)---[GND] | · P1 = Preset = 10 Kohm
+Ground (23)---[GND] ---- S ------( 3) V0 · P2 = Preset = 1 Kohm
+Ground (24)---[GND] | |
+Ground (25)---[GND] [GND]---[P2]---[R]---(20) LED -
+
+
+------------------------
+4. USERSPACE PROGRAMMING
+------------------------
+
+The cfag12864bfb describes a framebuffer device (/dev/fbX).
+
+It has a size of 1024 bytes = 1 Kbyte.
+Each bit represents one pixel. If the bit is high, the pixel will
+turn on. If the pixel is low, the pixel will turn off.
+
+You can use the framebuffer as a file: fopen, fwrite, fclose...
+Although the LCD won't get updated until the next refresh time arrives.
+
+Also, you can mmap the framebuffer: open & mmap, munmap & close...
+which is the best option for most uses.
+
+Check Documentation/auxdisplay/cfag12864b-example.c
+for a real working userspace complete program with usage examples.
diff --git a/Documentation/auxdisplay/cfag12864b-example.c b/Documentation/auxdisplay/cfag12864b-example.c
new file mode 100644
index 00000000000..7bfac354d4c
--- /dev/null
+++ b/Documentation/auxdisplay/cfag12864b-example.c
@@ -0,0 +1,282 @@
+/*
+ * Filename: cfag12864b-example.c
+ * Version: 0.1.0
+ * Description: cfag12864b LCD userspace example program
+ * License: GPLv2
+ *
+ * Author: Copyright (C) Miguel Ojeda Sandonis <maxextreme@gmail.com>
+ * Date: 2006-10-31
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+/*
+ * ------------------------
+ * start of cfag12864b code
+ * ------------------------
+ */
+
+#include <string.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+
+#define CFAG12864B_WIDTH (128)
+#define CFAG12864B_HEIGHT (64)
+#define CFAG12864B_SIZE (128 * 64 / 8)
+#define CFAG12864B_BPB (8)
+#define CFAG12864B_ADDRESS(x, y) ((y) * CFAG12864B_WIDTH / \
+ CFAG12864B_BPB + (x) / CFAG12864B_BPB)
+#define CFAG12864B_BIT(n) (((unsigned char) 1) << (n))
+
+#undef CFAG12864B_DOCHECK
+#ifdef CFAG12864B_DOCHECK
+ #define CFAG12864B_CHECK(x, y) ((x) < CFAG12864B_WIDTH && \
+ (y) < CFAG12864B_HEIGHT)
+#else
+ #define CFAG12864B_CHECK(x, y) (1)
+#endif
+
+int cfag12864b_fd;
+unsigned char * cfag12864b_mem;
+unsigned char cfag12864b_buffer[CFAG12864B_SIZE];
+
+/*
+ * init a cfag12864b framebuffer device
+ *
+ * No error: return = 0
+ * Unable to open: return = -1
+ * Unable to mmap: return = -2
+ */
+int cfag12864b_init(char *path)
+{
+ cfag12864b_fd = open(path, O_RDWR);
+ if (cfag12864b_fd == -1)
+ return -1;
+
+ cfag12864b_mem = mmap(0, CFAG12864B_SIZE, PROT_READ | PROT_WRITE,
+ MAP_SHARED, cfag12864b_fd, 0);
+ if (cfag12864b_mem == MAP_FAILED) {
+ close(cfag12864b_fd);
+ return -2;
+ }
+
+ return 0;
+}
+
+/*
+ * exit a cfag12864b framebuffer device
+ */
+void cfag12864b_exit(void)
+{
+ munmap(cfag12864b_mem, CFAG12864B_SIZE);
+ close(cfag12864b_fd);
+}
+
+/*
+ * set (x, y) pixel
+ */
+void cfag12864b_set(unsigned char x, unsigned char y)
+{
+ if (CFAG12864B_CHECK(x, y))
+ cfag12864b_buffer[CFAG12864B_ADDRESS(x, y)] |=
+ CFAG12864B_BIT(x % CFAG12864B_BPB);
+}
+
+/*
+ * unset (x, y) pixel
+ */
+void cfag12864b_unset(unsigned char x, unsigned char y)
+{
+ if (CFAG12864B_CHECK(x, y))
+ cfag12864b_buffer[CFAG12864B_ADDRESS(x, y)] &=
+ ~CFAG12864B_BIT(x % CFAG12864B_BPB);
+}
+
+/*
+ * is set (x, y) pixel?
+ *
+ * Pixel off: return = 0
+ * Pixel on: return = 1
+ */
+unsigned char cfag12864b_isset(unsigned char x, unsigned char y)
+{
+ if (CFAG12864B_CHECK(x, y))
+ if (cfag12864b_buffer[CFAG12864B_ADDRESS(x, y)] &
+ CFAG12864B_BIT(x % CFAG12864B_BPB))
+ return 1;
+
+ return 0;
+}
+
+/*
+ * not (x, y) pixel
+ */
+void cfag12864b_not(unsigned char x, unsigned char y)
+{
+ if (cfag12864b_isset(x, y))
+ cfag12864b_unset(x, y);
+ else
+ cfag12864b_set(x, y);
+}
+
+/*
+ * fill (set all pixels)
+ */
+void cfag12864b_fill(void)
+{
+ unsigned short i;
+
+ for (i = 0; i < CFAG12864B_SIZE; i++)
+ cfag12864b_buffer[i] = 0xFF;
+}
+
+/*
+ * clear (unset all pixels)
+ */
+void cfag12864b_clear(void)
+{
+ unsigned short i;
+
+ for (i = 0; i < CFAG12864B_SIZE; i++)
+ cfag12864b_buffer[i] = 0;
+}
+
+/*
+ * format a [128*64] matrix
+ *
+ * Pixel off: src[i] = 0
+ * Pixel on: src[i] > 0
+ */
+void cfag12864b_format(unsigned char * matrix)
+{
+ unsigned char i, j, n;
+
+ for (i = 0; i < CFAG12864B_HEIGHT; i++)
+ for (j = 0; j < CFAG12864B_WIDTH / CFAG12864B_BPB; j++) {
+ cfag12864b_buffer[i * CFAG12864B_WIDTH / CFAG12864B_BPB +
+ j] = 0;
+ for (n = 0; n < CFAG12864B_BPB; n++)
+ if (matrix[i * CFAG12864B_WIDTH +
+ j * CFAG12864B_BPB + n])
+ cfag12864b_buffer[i * CFAG12864B_WIDTH /
+ CFAG12864B_BPB + j] |=
+ CFAG12864B_BIT(n);
+ }
+}
+
+/*
+ * blit buffer to lcd
+ */
+void cfag12864b_blit(void)
+{
+ memcpy(cfag12864b_mem, cfag12864b_buffer, CFAG12864B_SIZE);
+}
+
+/*
+ * ----------------------
+ * end of cfag12864b code
+ * ----------------------
+ */
+
+#include <stdio.h>
+#include <string.h>
+
+#define EXAMPLES 6
+
+void example(unsigned char n)
+{
+ unsigned short i, j;
+ unsigned char matrix[CFAG12864B_WIDTH * CFAG12864B_HEIGHT];
+
+ if (n > EXAMPLES)
+ return;
+
+ printf("Example %i/%i - ", n, EXAMPLES);
+
+ switch (n) {
+ case 1:
+ printf("Draw points setting bits");
+ cfag12864b_clear();
+ for (i = 0; i < CFAG12864B_WIDTH; i += 2)
+ for (j = 0; j < CFAG12864B_HEIGHT; j += 2)
+ cfag12864b_set(i, j);
+ break;
+
+ case 2:
+ printf("Clear the LCD");
+ cfag12864b_clear();
+ break;
+
+ case 3:
+ printf("Draw rows formatting a [128*64] matrix");
+ memset(matrix, 0, CFAG12864B_WIDTH * CFAG12864B_HEIGHT);
+ for (i = 0; i < CFAG12864B_WIDTH; i++)
+ for (j = 0; j < CFAG12864B_HEIGHT; j += 2)
+ matrix[j * CFAG12864B_WIDTH + i] = 1;
+ cfag12864b_format(matrix);
+ break;
+
+ case 4:
+ printf("Fill the lcd");
+ cfag12864b_fill();
+ break;
+
+ case 5:
+ printf("Draw columns unsetting bits");
+ for (i = 0; i < CFAG12864B_WIDTH; i += 2)
+ for (j = 0; j < CFAG12864B_HEIGHT; j++)
+ cfag12864b_unset(i, j);
+ break;
+
+ case 6:
+ printf("Do negative not-ing all bits");
+ for (i = 0; i < CFAG12864B_WIDTH; i++)
+ for (j = 0; j < CFAG12864B_HEIGHT; j ++)
+ cfag12864b_not(i, j);
+ break;
+ }
+
+ puts(" - [Press Enter]");
+}
+
+int main(int argc, char *argv[])
+{
+ unsigned char n;
+
+ if (argc != 2) {
+ printf(
+ "Sintax: %s fbdev\n"
+ "Usually: /dev/fb0, /dev/fb1...\n", argv[0]);
+ return -1;
+ }
+
+ if (cfag12864b_init(argv[1])) {
+ printf("Can't init %s fbdev\n", argv[1]);
+ return -2;
+ }
+
+ for (n = 1; n <= EXAMPLES; n++) {
+ example(n);
+ cfag12864b_blit();
+ while (getchar() != '\n');
+ }
+
+ cfag12864b_exit();
+
+ return 0;
+}
diff --git a/Documentation/auxdisplay/ks0108 b/Documentation/auxdisplay/ks0108
new file mode 100644
index 00000000000..92b03b60c61
--- /dev/null
+++ b/Documentation/auxdisplay/ks0108
@@ -0,0 +1,55 @@
+ ==========================================
+ ks0108 LCD Controller Driver Documentation
+ ==========================================
+
+License: GPLv2
+Author & Maintainer: Miguel Ojeda Sandonis <maxextreme@gmail.com>
+Date: 2006-10-27
+
+
+
+--------
+0. INDEX
+--------
+
+ 1. DRIVER INFORMATION
+ 2. DEVICE INFORMATION
+ 3. WIRING
+
+
+---------------------
+1. DRIVER INFORMATION
+---------------------
+
+This driver support the ks0108 LCD controller.
+
+
+---------------------
+2. DEVICE INFORMATION
+---------------------
+
+Manufacturer: Samsung
+Device Name: KS0108 LCD Controller
+Device Code: ks0108
+Webpage: -
+Device Webpage: -
+Type: LCD Controller (Liquid Crystal Display Controller)
+Width: 64
+Height: 64
+Colors: 2 (B/N)
+Pages: 8
+Addresses: 64 each page
+Data size: 1 byte each address
+Memory size: 8 * 64 * 1 = 512 bytes
+
+
+---------
+3. WIRING
+---------
+
+The driver supports data parallel port wiring.
+
+If you aren't building LCD related hardware, you should check
+your LCD specific wiring information in the same folder.
+
+For example, check Documentation/auxdisplay/cfag12864b.
diff --git a/Documentation/cdrom/packet-writing.txt b/Documentation/cdrom/packet-writing.txt
index 7715d2247c4..cf1f8126991 100644
--- a/Documentation/cdrom/packet-writing.txt
+++ b/Documentation/cdrom/packet-writing.txt
@@ -93,7 +93,7 @@ Notes
Using the pktcdvd sysfs interface
---------------------------------
-Since Linux 2.6.19, the pktcdvd module has a sysfs interface
+Since Linux 2.6.20, the pktcdvd module has a sysfs interface
and can be controlled by it. For example the "pktcdvd" tool uses
this interface. (see http://people.freenet.de/BalaGi#pktcdvd )
diff --git a/Documentation/crypto/api-intro.txt b/Documentation/crypto/api-intro.txt
index 5a03a2801d6..e41a79aa71c 100644
--- a/Documentation/crypto/api-intro.txt
+++ b/Documentation/crypto/api-intro.txt
@@ -193,6 +193,7 @@ Original developers of the crypto algorithms:
Kartikey Mahendra Bhatt (CAST6)
Jon Oberheide (ARC4)
Jouni Malinen (Michael MIC)
+ NTT(Nippon Telegraph and Telephone Corporation) (Camellia)
SHA1 algorithm contributors:
Jean-Francois Dive
@@ -246,6 +247,9 @@ Tiger algorithm contributors:
VIA PadLock contributors:
Michal Ludvig
+Camellia algorithm contributors:
+ NTT(Nippon Telegraph and Telephone Corporation) (Camellia)
+
Generic scatterwalk code by Adam J. Richter <adam@yggdrasil.com>
Please send any credits updates or corrections to:
diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt
new file mode 100644
index 00000000000..5163b85308f
--- /dev/null
+++ b/Documentation/driver-model/devres.txt
@@ -0,0 +1,268 @@
+Devres - Managed Device Resource
+================================
+
+Tejun Heo <teheo@suse.de>
+
+First draft 10 January 2007
+
+
+1. Intro : Huh? Devres?
+2. Devres : Devres in a nutshell
+3. Devres Group : Group devres'es and release them together
+4. Details : Life time rules, calling context, ...
+5. Overhead : How much do we have to pay for this?
+6. List of managed interfaces : Currently implemented managed interfaces
+
+
+ 1. Intro
+ --------
+
+devres came up while trying to convert libata to use iomap. Each
+iomapped address should be kept and unmapped on driver detach. For
+example, a plain SFF ATA controller (that is, good old PCI IDE) in
+native mode makes use of 5 PCI BARs and all of them should be
+maintained.
+
+As with many other device drivers, libata low level drivers have
+sufficient bugs in ->remove and ->probe failure path. Well, yes,
+that's probably because libata low level driver developers are lazy
+bunch, but aren't all low level driver developers? After spending a
+day fiddling with braindamaged hardware with no document or
+braindamaged document, if it's finally working, well, it's working.
+
+For one reason or another, low level drivers don't receive as much
+attention or testing as core code, and bugs on driver detach or
+initilaization failure doesn't happen often enough to be noticeable.
+Init failure path is worse because it's much less travelled while
+needs to handle multiple entry points.
+
+So, many low level drivers end up leaking resources on driver detach
+and having half broken failure path implementation in ->probe() which
+would leak resources or even cause oops when failure occurs. iomap
+adds more to this mix. So do msi and msix.
+
+
+ 2. Devres
+ ---------
+
+devres is basically linked list of arbitrarily sized memory areas
+associated with a struct device. Each devres entry is associated with
+a release function. A devres can be released in several ways. No
+matter what, all devres entries are released on driver detach. On
+release, the associated release function is invoked and then the
+devres entry is freed.
+
+Managed interface is created for resources commonly used by device
+drivers using devres. For example, coherent DMA memory is acquired
+using dma_alloc_coherent(). The managed version is called
+dmam_alloc_coherent(). It is identical to dma_alloc_coherent() except
+for the DMA memory allocated using it is managed and will be
+automatically released on driver detach. Implementation looks like
+the following.
+