3 files changed, 244 insertions, 6 deletions

diff --git a/Documentation/arm/Sharp-LH/ADC-LH7-Touchscreen b/Documentation/arm/Sharp-LH/ADC-LH7-Touchscreen
new file mode 100644
index 000000000000..1e6a23fdf2fc
--- /dev/null
+++ b/Documentation/arm/Sharp-LH/ADC-LH7-Touchscreen
@@ -0,0 +1,61 @@
+README on the ADC/Touchscreen Controller
+========================================
+
+The LH79524 and LH7A404 include a built-in Analog to Digital
+controller (ADC) that is used to process input from a touchscreen.
+The driver only implements a four-wire touch panel protocol.
+
+The touchscreen driver is maintenance free except for the pen-down or
+touch threshold.  Some resistive displays and board combinations may
+require tuning of this threshold.  The driver exposes some of it's
+internal state in the sys filesystem.  If the kernel is configured
+with it, CONFIG_SYSFS, and sysfs is mounted at /sys, there will be a
+directory
+
+  /sys/devices/platform/adc-lh7.0
+
+containing these files.
+
+  -r--r--r--    1 root     root         4096 Jan  1 00:00 samples
+  -rw-r--r--    1 root     root         4096 Jan  1 00:00 threshold
+  -r--r--r--    1 root     root         4096 Jan  1 00:00 threshold_range
+
+The threshold is the current touch threshold.  It defaults to 750 on
+most targets.
+
+  # cat threshold
+ 750
+
+The threshold_range contains the range of valid values for the
+threshold.  Values outside of this range will be silently ignored.
+
+  # cat threshold_range
+  0 1023
+
+To change the threshold, write a value to the threshold file.
+
+  # echo 500 > threshold
+  # cat threshold
+  500
+
+The samples file contains the most recently sampled values from the
+ADC.  There are 12.  Below are typical of the last sampled values when
+the pen has been released.  The first two and last two samples are for
+detecting whether or not the pen is down.  The third through sixth are
+X coordinate samples.  The seventh through tenth are Y coordinate
+samples.
+
+  # cat samples
+  1023 1023 0 0 0 0 530 529 530 529 1023 1023
+
+To determine a reasonable threshold, press on the touch panel with an
+appropriate stylus and read the values from samples.
+
+  # cat samples
+  1023 676 92 103 101 102 855 919 922 922 1023 679
+
+The first and eleventh samples are discarded.  Thus, the important
+values are the second and twelfth which are used to determine if the
+pen is down.  When both are below the threshold, the driver registers
+that the pen is down.  When either is above the threshold, it
+registers then pen is up.
diff --git a/Documentation/arm/Sharp-LH/LCDPanels b/Documentation/arm/Sharp-LH/LCDPanels
new file mode 100644
index 000000000000..fb1b21c2f2f4
--- /dev/null
+++ b/Documentation/arm/Sharp-LH/LCDPanels
@@ -0,0 +1,59 @@
+README on the LCD Panels
+========================
+
+Configuration options for several LCD panels, available from Logic PD,
+are included in the kernel source.  This README will help you
+understand the configuration data and give you some guidance for
+adding support for other panels if you wish.
+
+
+lcd-panels.h
+------------
+
+There is no way, at present, to detect which panel is attached to the
+system at runtime.  Thus the kernel configuration is static.  The file
+arch/arm/mach-ld7a40x/lcd-panels.h (or similar) defines all of the
+panel specific parameters.
+
+It should be possible for this data to be shared among several device
+families.  The current layout may be insufficiently general, but it is
+amenable to improvement.
+
+
+PIXEL_CLOCK
+-----------
+
+The panel data sheets will give a range of acceptable pixel clocks.
+The fundamental LCDCLK input frequency is divided down by a PCD
+constant in field '.tim2'.  It may happen that it is impossible to set
+the pixel clock within this range.  A clock which is too slow will
+tend to flicker.  For the highest quality image, set the clock as high
+as possible.
+
+
+MARGINS
+-------
+
+These values may be difficult to glean from the panel data sheet.  In
+the case of the Sharp panels, the upper margin is explicitly called
+out as a specific number of lines from the top of the frame.  The
+other values may not matter as much as the panels tend to
+automatically center the image.
+
+
+Sync Sense
+----------
+
+The sense of the hsync and vsync pulses may be called out in the data
+sheet.  On one panel, the sense of these pulses determine the height
+of the visible region on the panel.  Most of the Sharp panels use
+negative sense sync pulses set by the TIM2_IHS and TIM2_IVS bits in
+'.tim2'.
+
+
+Pel Layout
+----------
+
+The Sharp color TFT panels are all configured for 16 bit direct color
+modes.  The amba-lcd driver sets the pel mode to 565 for 5 bits of
+each red and blue and 6 bits of green.
diff --git a/Documentation/filesystems/inotify.txt b/Documentation/filesystems/inotify.txt
index 6d501903f68e..59a919f16144 100644
--- a/Documentation/filesystems/inotify.txt
+++ b/Documentation/filesystems/inotify.txt
@@ -69,17 +69,135 @@ Prototypes:
         int inotify_rm_watch (int fd, __u32 mask);
 
 
-(iii) Internal Kernel Implementation
+(iii) Kernel Interface
 
-Each inotify instance is associated with an inotify_device structure.
+Inotify's kernel API consists a set of functions for managing watches and an
+event callback.
+
+To use the kernel API, you must first initialize an inotify instance with a set
+of inotify_operations.  You are given an opaque inotify_handle, which you use
+for any further calls to inotify.
+
+    struct inotify_handle *ih = inotify_init(my_event_handler);
+
+You must provide a function for processing events and a function for destroying
+the inotify watch.
+
+    void handle_event(struct inotify_watch *watch, u32 wd, u32 mask,
+                      u32 cookie, const char *name, struct inode *inode)
+
+        watch - the pointer to the inotify_watch that triggered this call
+        wd - the watch descriptor
+        mask - describes the event that occurred
+        cookie - an identifier for synchronizing events
+        name - the dentry name for affected files in a directory-based event
+        inode - the affected inode in a directory-based event
+
+    void destroy_watch(struct inotify_watch *watch)
+
+You may add watches by providing a pre-allocated and initialized inotify_watch
+structure and specifying the inode to watch along with an inotify event mask.
+You must pin the inode during the call.  You will likely wish to embed the
+inotify_watch structure in a structure of your own which contains other
+information about the watch.  Once you add an inotify watch, it is immediately
+subject to removal depending on filesystem events.  You must grab a reference if
+you depend on the watch hanging around after the call.
+
+    inotify_init_watch(&my_watch->iwatch);
+    inotify_get_watch(&my_watch->iwatch);       // optional
+    s32 wd = inotify_add_watch(ih, &my_watch->iwatch, inode, mask);
+    inotify_put_watch(&my_watch->iwatch);       // optional
+
+You may use the watch descriptor (wd) or the address of the inotify_watch for
+other inotify operations.  You must not directly read or manipulate data in the
+inotify_watch.  Additionally, you must not call inotify_add_watch() more than
+once for a given inotify_watch structure, unless you have first called either
+inotify_rm_watch() or inotify_rm_wd().
+
+To determine if you have already registered a watch for a given inode, you may
+call inotify_find_watch(), which gives you both the wd and the watch pointer for
+the inotify_watch, or an error if the watch does not exist.
+
+    wd = inotify_find_watch(ih, inode, &watchp);
+
+You may use container_of() on the watch pointer to access your own data
+associated with a given watch.  When an existing watch is found,
+inotify_find_watch() bumps the refcount before releasing its locks.  You must
+put that reference with:
+
+    put_inotify_watch(watchp);
+
+Call inotify_find_update_watch() to update the event mask for an existing watch.
+inotify_find_update_watch() returns the wd of the updated watch, or an error if
+the watch does not exist.
+
+    wd = inotify_find_update_watch(ih, inode, mask);
+
+An existing watch may be removed by calling either inotify_rm_watch() or
+inotify_rm_wd().
+
+    int ret = inotify_rm_watch(ih, &my_watch->iwatch);
+    int ret = inotify_rm_wd(ih, wd);
+
+A watch may be removed while executing your event handler with the following:
+
+    inotify_remove_watch_locked(ih, iwatch);
+
+Call inotify_destroy() to remove all watches from your inotify instance and
+release it.  If there are no outstanding references, inotify_destroy() will call
+your destroy_watch op for each watch.
+
+    inotify_destroy(ih);
+
+When inotify removes a watch, it sends an IN_IGNORED event to your callback.
+You may use this event as an indication to free the watch memory.  Note that
+inotify may remove a watch due to filesystem events, as well as by your request.
+If you use IN_ONESHOT, inotify will remove the watch after the first event, at
+which point you may call the final inotify_put_watch.
+
+(iv) Kernel Interface Prototypes
+
+        struct inotify_handle *inotify_init(struct inotify_operations *ops);
+
+        inotify_init_watch(struct inotify_watch *watch);
+
+        s32 inotify_add_watch(struct inotify_handle *ih,
+                              struct inotify_watch *watch,
+                              struct inode *inode, u32 mask);
+
+        s32 inotify_find_watch(struct inotify_handle *ih, struct inode *inode,
+                               struct inotify_watch **watchp);
+
+        s32 inotify_find_update_watch(struct inotify_handle *ih,
+                                      struct inode *inode, u32 mask);
+
+        int inotify_rm_wd(struct inotify_handle *ih, u32 wd);
+
+        int inotify_rm_watch(struct inotify_handle *ih,
+                             struct inotify_watch *watch);
+
+        void inotify_remove_watch_locked(struct inotify_handle *ih,
+                                         struct inotify_watch *watch);
+
+        void inotify_destroy(struct inotify_handle *ih);
+
+        void get_inotify_watch(struct inotify_watch *watch);
+        void put_inotify_watch(struct inotify_watch *watch);
+
+
+(v) Internal Kernel Implementation
+
+Each inotify instance is represented by an inotify_handle structure.
+Inotify's userspace consumers also have an inotify_device which is
+associated with the inotify_handle, and on which events are queued.
 
 Each watch is associated with an inotify_watch structure.  Watches are chained
-off of each associated device and each associated inode.
+off of each associated inotify_handle and each associated inode.
 
-See fs/inotify.c for the locking and lifetime rules.
+See fs/inotify.c and fs/inotify_user.c for the locking and lifetime rules.
 
 
-(iv) Rationale
+(vi) Rationale
 
 Q: What is the design decision behind not tying the watch to the open fd of
    the watched object?
@@ -145,7 +263,7 @@ A: The poor user-space interface is the second biggest problem with dnotify.
    file descriptor-based one that allows basic file I/O and poll/select.
    Obtaining the fd and managing the watches could have been done either via a
    device file or a family of new system calls.  We decided to implement a
-   family of system calls because that is the preffered approach for new kernel
+   family of system calls because that is the preferred approach for new kernel
    interfaces.  The only real difference was whether we wanted to use open(2)
    and ioctl(2) or a couple of new system calls.  System calls beat ioctls.