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| | * | regmap: Bypass the cache when applying patchesMark Brown2012-01-251-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Otherwise any patch that affects a register which is writable may trash cached values. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
| | * | regmap: Skip patch application when the cache is not dirty on syncMark Brown2012-01-251-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | On the basis that if we don't actually need to resync the cache then the patches are probably also already applied. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
| | * | regmap: Support register patch setsMark Brown2012-01-231-0/+11
| | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Device manufacturers frequently provide register sequences, usually not fully documented, to be run at startup in order to provide better defaults for devices (for example, improving performance in the light of silicon evaluation). Support such updates by allowing drivers to register update sets with the core. These updates will be written to the device immediately and will also be rewritten when the cache is synced. The assumption is that the reason for resyncing the cache will always be that the device has been powered off. If this turns out to not be the case then a separate operation can be provided. Currently the implementation only allows a single set of updates to be specified for a device, this could be extended in future. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
| * / regmap: Fix cache defaults initialization from raw cache defaultsLars-Peter Clausen2012-02-151-2/+2
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently registers with a value of 0 are ignored when initializing the register defaults from raw defaults. This worked in the past, because registers without a explicit default were assumed to have a default value of 0. This was changed in commit b03622a8 ("regmap: Ensure rbtree syncs registers set to zero properly"). As a result registers, which have a raw default value of 0 are now assumed to have no default. This again can result in unnecessary writes when syncing the cache. It will also result in unnecessary reads for e.g. the first update operation. In the case where readback is not possible this will even let the update operation fail, if the register has not been written to before. So this patch removes the check. Instead it adds a check to ignore raw defaults for registers which are volatile, since those registers are not cached. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: stable@vger.kernel.org
* | regmap: Add tracepoints for cache only and cache bypassMark Brown2012-02-231-0/+2
| | | | | | | | | | | | Useful for figuring out where the hardware interaction went or came from. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* | regmap: Implement support for 32 bit registers and valuesMark Brown2012-02-171-0/+11
| | | | | | | | Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* | regmap: Remove incorrect unreachable comment in regcache_set_val()Axel Lin2012-01-311-1/+0
| | | | | | | | | | | | | | | | regcache_set_val() returns false if cache[idx] != val. Thus it actually is not unreachable. Signed-off-by: Axel Lin <axel.lin@gmail.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* | regmap: Unexport regcache_write() and regcache_read()Mark Brown2012-01-251-2/+0
|/ | | | | | | | They have no current users which is fortunate as they don't take the lock and therefore aren't safe to use externally. We'll need to add new operations if direct cache access is needed. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Add trace event for successful cache readsMark Brown2011-11-301-2/+10
| | | | | | | Currently we only trace physical reads, there's no instrumentation if the read is satisfied from cache. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Remove indexed cache typeMark Brown2011-11-201-20/+0
| | | | | | | There should be no situation where it offers any advantage over rbtree and there are no current users so remove the code for simplicity. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Drop check whether a register is readable in regcache_readLars-Peter Clausen2011-11-171-3/+0
| | | | | | | | | | | | | One of the reasons for using a cache is to have a software shadow of a register which is writable but not readable. This allows us to do a read-modify-write operation on such a register. Currently regcache checks whether a register is readable when performing a cached read and returns an error if it is not. Drop this check, since it will prevent us from using the cache for registers where read-back is not possible. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Properly round cache_word_sizeLars-Peter Clausen2011-11-171-2/+2
| | | | | | | | | | regcache currently only properly works with val bit sizes of 8 or 16, since it will, when calculating the cache word size, round down. This causes the cache storage to be too small to hold the full register value. Fix this by rounding up instead. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Make reg_config reg_defaults constLars-Peter Clausen2011-11-161-3/+2
| | | | | | | | | | | | The reg_defaults field usually points to a static per driver array, which should not be modified. Make requirement this explicit by making reg_defaults const. To allow this the regcache_init code needs some minor changes. Previoulsy the reg_config was not available in regcache_init and regmap->reg_defaults was used to pass the default register set to regcache_init. Now that the reg_config is available we can work on it directly. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Move initialization of regcache related fields to regcache_initLars-Peter Clausen2011-11-161-1/+8
| | | | | | | | | Move the initialization regcache related fields of the regmap struct to regcache_init. This allows us to keep regmap and regcache code better separated. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Fix memory leak in regcache_init error pathLars-Peter Clausen2011-11-141-1/+10
| | | | | | | | | Make sure all allocated memory gets freed again in case initializing the cache failed. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Fix memory leak in regcache_hw_init error pathLars-Peter Clausen2011-11-141-2/+10
| | | | | | | | Make sure reg_defaults_raw gets freed in case of an error. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Track if the register cache is dirty and suppress unneeded syncsMark Brown2011-11-081-0/+19
| | | | | | | | | Allow drivers to optimise out the register cache sync if they didn't need to do one. If the hardware is desynced from the register cache (by power loss for example) then the driver should call regcache_mark_dirty() to let the core know about this. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* drivers/base: Add export.h for EXPORT_SYMBOL/THIS_MODULE as required.Paul Gortmaker2011-10-311-0/+1
| | | | | | | | | | Most of these files were implicitly getting EXPORT_SYMBOL via device.h which was including module.h, but that path will be broken soon. [ with input from Stephen Rothwell <sfr@canb.auug.org.au> ] Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* regmap: Allow caches for devices with no defaultsMark Brown2011-10-101-1/+1
| | | | | | | | | | | | | | | We only really need the defaults in order to cut down the number of registers we sync and to satisfy reads while the device is powered off but not all devices are going to need to do that (always on devices like PMICs being the prime example) so don't require those devices to supply a default. Instead only try to fall back to hardware defaults if the driver told us to. Devices using LZO won't be able to instantiate with this, that will require some updates in the LZO code to handle this case. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
* regmap: Return a sensible error code if we fail to read the cacheMark Brown2011-10-101-1/+1
| | | | | | | | If a register isn't cached then let callers know that so they can fall back or error handle appropriately. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
* regmap: Use bsearch() to search the register defaultsMark Brown2011-10-091-20/+20
| | | | | | | | | | Rather than open coding a binary search use the standard bsearch() using the comparison function we're already using for sort() on insert. This fixes a lockup I was observing due to iterating on min <= max rather than min < max when we fail to look up. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
* regmap: Fix doc commentDimitris Papastamos2011-10-031-1/+1
| | | | | Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Optimize the lookup path to use binary searchDimitris Papastamos2011-10-031-5/+24
| | | | | | | | | | Since there are more lookups than insertions in a typical scenario, optimize the linear search into a binary search. For this to work, we need to keep reg_defaults sorted upon insertions, for now be lazy and use sort(). Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Ensure we scream if we enable cache bypass/only at the same timeDimitris Papastamos2011-09-301-0/+2
| | | | | Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Implement regcache_cache_bypass helper functionDimitris Papastamos2011-09-301-0/+19
| | | | | | | | Ensure we've got a function so users can enable/disable the cache bypass option. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Save/restore the bypass state upon syncingDimitris Papastamos2011-09-301-0/+5
| | | | | Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Lock the sync path, ensure we use the lockless _regmap_write()Dimitris Papastamos2011-09-301-1/+3
| | | | | Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Fix apostrophe usageMark Brown2011-09-301-1/+1
| | | | | | An apostrophe does not mean "look out, here comes an s!". Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Fix lock used for regcache_cache_only()Mark Brown2011-09-291-2/+2
| | | | | Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Grab the lock in regcache_cache_only()Dimitris Papastamos2011-09-281-0/+2
| | | | | Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Modify map->cache_bypass directlyDimitris Papastamos2011-09-281-2/+2
| | | | | | | | | In preperation for the upcoming patches, modify map->cache_bypass directly. The helper functions will grab an exclusive lock. Because we'll have acquired the same lock we need to avoid a deadlock. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Fix regcache_sync generic implementationDimitris Papastamos2011-09-281-1/+1
| | | | | | | | We want to use regmap_write() to actually write anything to the HW. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Implement generic syncing functionalityDimitris Papastamos2011-09-271-7/+26
| | | | | | | | | In the absence of a sync callback, do it manually. This of course can't take advantange of the specific optimizations of each cache type but it will do well enough in most cases. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Allow drivers to control cache_only flagMark Brown2011-09-191-0/+18
| | | | Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: A cache type of _NONE behaves like a bypassed cacheMark Brown2011-09-191-1/+3
| | | | | | | Avoid extra special casing by setting the cache_bypass flag when we're not caching. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Add the regcache_sync trace eventDimitris Papastamos2011-09-191-1/+7
| | | | | Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Add the LZO cache supportDimitris Papastamos2011-09-191-0/+1
| | | | | | | | | | | | | | | | | | This patch adds support for LZO compression when storing the register cache. For a typical device whose register map would normally occupy 25kB or 50kB by using the LZO compression technique, one can get down to ~5-7kB. There might be a performance penalty associated with each individual read/write due to decompressing/compressing the underlying cache, however that should not be noticeable. These memory benefits depend on whether the target architecture can get rid of the memory occupied by the original register defaults cache which is marked as __devinitconst. Nevertheless there will be some memory gain even if the target architecture can't get rid of the original register map, this should be around ~30-32kB instead of 50kB. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Add the rbtree cache supportDimitris Papastamos2011-09-191-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | This patch adds support for the rbtree cache compression type. Each rbnode manages a variable length block of registers. There can be no two nodes with overlapping blocks. Each block has a base register and a currently top register, all the other registers, if any, lie in between these two and in ascending order. The reasoning behind the construction of this rbtree is simple. In the snd_soc_rbtree_cache_init() function, we iterate over the register defaults provided by the regcache core. For each register value that is non-zero we insert it in the rbtree. In order to determine in which rbnode we need to add the register, we first look if there is another register already added that is adjacent to the one we are about to add. If that is the case we append it in that rbnode block, otherwise we create a new rbnode with a single register in its block and add it to the tree. There are various optimizations across the implementation to speed up lookups by caching the most recently used rbnode. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Add the indexed cache supportDimitris Papastamos2011-09-191-0/+1
| | | | | | | | | | | | This is the simplest form of a cache available in regcache. Any registers whose default value is 0 are ignored. If any of those registers are modified in the future, they will be placed in the cache on demand. The cache layout is essentially using the provided register defaults by the regcache core directly and does not re-map it to another representation. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
* regmap: Introduce caching supportDimitris Papastamos2011-09-191-0/+304
This patch introduces caching support for regmap. The regcache API has evolved essentially out of ASoC soc-cache so most of the actual caching types (except LZO) have been tested in the past. The purpose of regcache is to optimize in time and space the handling of register caches. Time optimization is achieved by not having to go over a slow bus like I2C to read the value of a register, instead it is cached locally in memory and can be retrieved faster. Regarding space optimization, some of the cache types are better at packing the caches, for e.g. the rbtree and the LZO caches. By doing this the sacrifice in time still wins over doing I2C transactions. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Tested-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
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