When inserting a new register into a block at the lower end the present
bitmap is currently shifted into the wrong direction. The effect of this is
that the bitmap becomes corrupted and registers which are present might be
reported as not present and vice versa.

Fix this by shifting left rather than right.

Fixes: 472fdec7380c("regmap: rbtree: Reduce number of nodes, take 2")
Reported-by: Daniel Baluta <daniel.baluta@gmail.com>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

If the inlcude headers aren't sorted alphabetically, then the
logical choice is to append new ones, however that creates a
lot of potential for conflicts or duplicates because every change
will then add new includes in the same location.

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

Commit 6cfec04bcc05 ("regmap: Separate regmap dev initialization") moved the
regmap debugfs initialization after regcache initialization. This means
that the regmap debugfs directory is not created yet when the cache
initialization runs and so any debugfs files registered by the regcache are
created in the debugfs root directory rather than the debugfs directory of
the regmap instance. Fix this by adding a separate callback for the
regcache debugfs initialization which will be called after the parent
debugfs entry has been created.

Fixes: 6cfec04bcc05 (regmap: Separate regmap dev initialization)
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
Cc: stable@vger.kernel.org

Change regcache_rbtree_node strcuture fields order to align the pointers on
64bits architectures.

Signed-off-by: Jean-Christophe PINCE <jean-christophe.pince@intel.com>
Signed-off-by: David Cohen <david.a.cohen@linux.intel.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

Pull regmap updates from Mark Brown:
 "A quiet release for regmap, some cleanups, fixes and:

   - Improved node coalescing for rbtree, reducing memory usage and
     improving performance during syncs.
   - Support for registering multiple register patches.
   - A quirk for handling interrupts that need to be clear when masked
     in regmap-irq"

* tag 'regmap-v3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
  regmap: rbtree: Make cache_present bitmap per node
  regmap: rbtree: Reduce number of nodes, take 2
  regmap: rbtree: Simplify adjacent node look-up
  regmap: debugfs: Fix continued read from registers file
  regcache-rbtree: Fix reg_stride != 1
  regmap: Allow multiple patches to be registered
  regmap: regcache: allow read-only regs to be cached
  regmap: fix regcache_reg_present() for empty cache
  regmap: core: allow a virtual range to cover its own data window
  regmap: irq: document mask/wake_invert flags
  regmap: irq: make flags bool and put them in a bitfield
  regmap: irq: Allow to acknowledge masked interrupts during initialization
  regmap: Provide __acquires/__releases annotations

With devices which have a dense and small register map but placed at a large
offset the global cache_present bitmap imposes a huge memory overhead. Making
the cache_present per rbtree node avoids the issue and easily reduces the memory
footprint by a factor of ten. For devices with a more sparse map or without a
large base register offset the memory usage might increase slightly by a few
bytes, but not significantly. E.g. for a device which has ~50 registers at
offset 0x4000 the memory footprint of the register cache goes down form 2496
bytes to 175 bytes.

Moving the bitmap to a per node basis means that the handling of the bitmap is
now cache implementation specific and can no longer be managed by the core. The
regcache_sync_block() function is extended by a additional parameter so that the
cache implementation can tell the core which registers in the block are set and
which are not. The parameter is optional and if NULL the core assumes that all
registers are set. The rbtree cache also needs to implement its own drop
callback instead of relying on the core to handle this.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@linaro.org>

Support for reducing the number of nodes and memory consumption of the rbtree
cache by allowing for small unused holes in the node's register cache block was
initially added in commit 0c7ed856 ("regmap: Cut down on the average # of nodes
in the rbtree cache"). But the commit had problems and so its effect was
reverted again in commit 4e67fb5 ("regmap: rbtree: Fix overlapping rbnodes.").
This patch brings the feature back of reducing the average number of nodes,
which will speedup node look-up, while at the same time also reducing the memory
usage of the rbtree cache. This patch takes a slightly different approach than
the original patch though. It modifies the adjacent node look-up to not only
consider nodes that are just one to the left or the right of the register but
any node that falls in a certain range around the register. The range is
calculated based on how much memory it would take to allocate a new node
compared to how much memory it takes adding a set of unused registers to an
existing node. E.g. if a node takes up 24 bytes and each register in a block
uses 1 byte the range will be from the register address - 24 to the register
address + 24. If we find a node that falls within this range it is cheaper or as
expensive to add the register to the existing node and have a couple of unused
registers in the node's cache compared to allocating a new node.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@linaro.org>

A register which is adjacent to a node will either be left to the first
register or right to the last register. It will not be within the node's range,
so there is no point in checking for each register cached by the node whether
the new register is next to it. It is sufficient to check whether the register
comes before the first register or after the last register of the node.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@linaro.org>

There are a couple of calculations, which convert between register addresses and
block indices, in regcache_rbtree_sync() and regcache_rbtree_node_alloc() which
assume that reg_stride is 1. This will break the rb cache for configurations
which do not use a reg_stride of 1.

Also rename 'base' in regcache_rbtree_sync() to 'start' to avoid confusion with
'base_reg'.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@linaro.org>

Avoid overlapping register regions by making the initial blklen of a new
node 1. If a register write occurs to a yet uncached register, that is
lower than but near an existing node's base_reg, a new node is created
and it's blklen is set to an arbitrary value (sizeof(*rbnode)). That may
cause this node to overlap with another node. Those nodes should be merged,
but this merge doesn't happen yet, so this patch at least makes the initial
blklen small enough to avoid hitting the wrong node, which may otherwise
lead to severe breakage.

Signed-off-by: David Jander <david@protonic.nl>
Signed-off-by: Mark Brown <broonie@linaro.org>
Cc: stable@vger.kernel.org