The regmap config does not prohibit val_bytes that are not powers of
two. But the current code of regmap_bulk_write for use_single_rw does
limit the possible val_bytes to 1, 2 and 4.

This patch fixes the behaviour to allow bus writes with non-standard
val_bytes sizes.

Cc: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NMarkus Pargmann <mpa@pengutronix.de>
Signed-off-by: NMark Brown <broonie@kernel.org>

Zero length reads make no sense in a regmap context and are likely to
trigger bugs further down the stack so insert an error check, also
silencing compiler warnings about use of ret in cases where we iterate
per register.
Reported-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NMark Brown <broonie@kernel.org>

Currently regmap requires that a reg_read callback is supplied, otherwise a
warning is emitted each time regmap_read() is called. This means a device
or bus without readback support needs to supply dummy reg_read callback.
Apart from that regmap_read() will still work fine if a cache is used.

Remove the warning and let regmap_readable() return false if not reg_read
callback is supplied. This means a device no longer has to supply a dummy
callback if it does not support readback and it also doesn't have to have a
readable_reg callback that always returns false since this is now implicit.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NMark Brown <broonie@kernel.org>

The way the mask is generated in regmap_field_init() is wrong.
Indeed, a field initialized with msb = 31 and lsb = 0 provokes a shift
overflow while calculating the mask field.

On some 32 bits architectures, such as x86, the generated mask is 0,
instead of the expected 0xffffffff.

This patch uses GENMASK() to fix the problem, as this macro is already safe
regarding shift overflow.
Signed-off-by: NMaxime Coquelin <maxime.coquelin@st.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

In big endian mode regmap_bulk_read gives incorrect data
for byte reads.

This is because memcpy of a single byte from an address
after full word read gives different results when
endianness differs. ie. we get little-end in LE and big-end in BE.
Signed-off-by: NArun Chandran <achandran@mvista.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

Delete jump to a label on the next line, when that label is not
used elsewhere.

A simplified version of the semantic patch that makes this change is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@r@
identifier l;
@@

-if (...) goto l;
-l:
// </smpl>
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NMark Brown <broonie@kernel.org>

This patch introduces regmap_get_reg_stride() function which would
be used by the infrastructures like nvmem framework built on top of
regmap. Mostly this function would be used for sanity checks on inputs
within such infrastructure.
Signed-off-by: NSrinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

This patch introduces regmap_get_max_register() function which would be
used by the infrastructures like nvmem framework built on top of
regmap.
Signed-off-by: NSrinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

The tracing events for regmap are confined to the regmap subsystem. It
also requires accessing an internal header. Instead of including the
internal header from a generic file location, move the tracing file
into the regmap directory.

Also rename the regmap tracing header to trace.h, as it is redundant to
keep the regmap.h name when it is in the regmap directory.
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

This patch fixes a NULL pointer dereference when enabling regmap event
tracing in the presence of a syscon regmap, introduced by commit bdb0066d
("mfd: syscon: Decouple syscon interface from platform devices").
That patch introduced syscon regmaps that have their dev field set to NULL.
The regmap trace events expect it to point to a valid struct device and feed
it to dev_name():

  $ echo 1 > /sys/kernel/debug/tracing/events/regmap/enable

  Unable to handle kernel NULL pointer dereference at virtual address 0000002c
  pgd = 80004000
  [0000002c] *pgd=00000000
  Internal error: Oops: 17 [#1] SMP ARM
  Modules linked in: coda videobuf2_vmalloc
  CPU: 0 PID: 304 Comm: kworker/0:2 Not tainted 4.0.0-rc2+ #9197
  Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
  Workqueue: events_freezable thermal_zone_device_check
  task: 9f25a200 ti: 9f1ee000 task.ti: 9f1ee000
  PC is at ftrace_raw_event_regmap_block+0x3c/0xe4
  LR is at _regmap_raw_read+0x1bc/0x1cc
  pc : [<803636e8>]    lr : [<80365f2c>]    psr: 600f0093
  sp : 9f1efd78  ip : 9f1efdb8  fp : 9f1efdb4
  r10: 00000004  r9 : 00000001  r8 : 00000001
  r7 : 00000180  r6 : 00000000  r5 : 9f00e3c0  r4 : 00000003
  r3 : 00000001  r2 : 00000180  r1 : 00000000  r0 : 9f00e3c0
  Flags: nZCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
  Control: 10c5387d  Table: 2d91004a  DAC: 00000015
  Process kworker/0:2 (pid: 304, stack limit = 0x9f1ee210)
  Stack: (0x9f1efd78 to 0x9f1f0000)
  fd60:                                                       9f1efda4 9f1efd88
  fd80: 800708c0 805f9510 80927140 800f0013 9f1fc800 9eb2f490 00000000 00000180
  fda0: 808e3840 00000001 9f1efdfc 9f1efdb8 80365f2c 803636b8 805f8958 800708e0
  fdc0: a00f0013 803636ac 9f16de00 00000180 80927140 9f1fc800 9f1fc800 9f1efe6c
  fde0: 9f1efe6c 9f732400 00000000 00000000 9f1efe1c 9f1efe00 80365f70 80365d7c
  fe00: 80365f3c 9f1fc800 9f1fc800 00000180 9f1efe44 9f1efe20 803656a4 80365f48
  fe20: 9f1fc800 00000180 9f1efe6c 9f1efe6c 9f732400 00000000 9f1efe64 9f1efe48
  fe40: 803657bc 80365634 00000001 9e95f910 9f1fc800 9f1efeb4 9f1efe8c 9f1efe68
  fe60: 80452ac0 80365778 9f1efe8c 9f1efe78 9e93d400 9e93d5e8 9f1efeb4 9f72ef40
  fe80: 9f1efeac 9f1efe90 8044e11c 80452998 8045298c 9e93d608 9e93d400 808e1978
  fea0: 9f1efecc 9f1efeb0 8044fd14 8044e0d0 ffffffff 9f25a200 9e93d608 9e481380
  fec0: 9f1efedc 9f1efed0 8044fde8 8044fcec 9f1eff1c 9f1efee0 80038d50 8044fdd8
  fee0: 9f1ee020 9f72ef40 9e481398 00000000 00000008 9f72ef54 9f1ee020 9f72ef40
  ff00: 9e481398 9e481380 00000008 9f72ef40 9f1eff5c 9f1eff20 80039754 80038bfc
  ff20: 00000000 9e481380 80894100 808e1662 00000000 9e4f2ec0 00000000 9e481380
  ff40: 800396f8 00000000 00000000 00000000 9f1effac 9f1eff60 8003e020 80039704
  ff60: ffffffff 00000000 ffffffff 9e481380 00000000 00000000 9f1eff78 9f1eff78
  ff80: 00000000 00000000 9f1eff88 9f1eff88 9e4f2ec0 8003df30 00000000 00000000
  ffa0: 00000000 9f1effb0 8000eb60 8003df3c 00000000 00000000 00000000 00000000
  ffc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
  ffe0: 00000000 00000000 00000000 00000000 00000013 00000000 ffffffff ffffffff
  Backtrace:
  [<803636ac>] (ftrace_raw_event_regmap_block) from [<80365f2c>] (_regmap_raw_read+0x1bc/0x1cc)
   r9:00000001 r8:808e3840 r7:00000180 r6:00000000 r5:9eb2f490 r4:9f1fc800
  [<80365d70>] (_regmap_raw_read) from [<80365f70>] (_regmap_bus_read+0x34/0x6c)
   r10:00000000 r9:00000000 r8:9f732400 r7:9f1efe6c r6:9f1efe6c r5:9f1fc800
   r4:9f1fc800
  [<80365f3c>] (_regmap_bus_read) from [<803656a4>] (_regmap_read+0x7c/0x144)
   r6:00000180 r5:9f1fc800 r4:9f1fc800 r3:80365f3c
  [<80365628>] (_regmap_read) from [<803657bc>] (regmap_read+0x50/0x70)
   r9:00000000 r8:9f732400 r7:9f1efe6c r6:9f1efe6c r5:00000180 r4:9f1fc800
  [<8036576c>] (regmap_read) from [<80452ac0>] (imx_get_temp+0x134/0x1a4)
   r6:9f1efeb4 r5:9f1fc800 r4:9e95f910 r3:00000001
  [<8045298c>] (imx_get_temp) from [<8044e11c>] (thermal_zone_get_temp+0x58/0x74)
   r7:9f72ef40 r6:9f1efeb4 r5:9e93d5e8 r4:9e93d400
  [<8044e0c4>] (thermal_zone_get_temp) from [<8044fd14>] (thermal_zone_device_update+0x34/0xec)
   r6:808e1978 r5:9e93d400 r4:9e93d608 r3:8045298c
  [<8044fce0>] (thermal_zone_device_update) from [<8044fde8>] (thermal_zone_device_check+0x1c/0x20)
   r5:9e481380 r4:9e93d608
  [<8044fdcc>] (thermal_zone_device_check) from [<80038d50>] (process_one_work+0x160/0x3d4)
  [<80038bf0>] (process_one_work) from [<80039754>] (worker_thread+0x5c/0x4f4)
   r10:9f72ef40 r9:00000008 r8:9e481380 r7:9e481398 r6:9f72ef40 r5:9f1ee020
   r4:9f72ef54
  [<800396f8>] (worker_thread) from [<8003e020>] (kthread+0xf0/0x108)
   r10:00000000 r9:00000000 r8:00000000 r7:800396f8 r6:9e481380 r5:00000000
   r4:9e4f2ec0
  [<8003df30>] (kthread) from [<8000eb60>] (ret_from_fork+0x14/0x34)
   r7:00000000 r6:00000000 r5:8003df30 r4:9e4f2ec0
  Code: e3140040 1a00001a e3140020 1a000016 (e596002c)
  ---[ end trace 193c15c2494ec960 ]---

Fixes: bdb0066d (mfd: syscon: Decouple syscon interface from platform devices)
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

We'll need to call it from regmap-i2c.c, which can be built as module.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NMark Brown <broonie@kernel.org>

Since we cannot make sure the 'val_count' will always be none zero
here, and then if it equals to zero, the kmemdup() will return
ZERO_SIZE_PTR, which equals to ((void *)16).

So this patch fix this with just doing the zero check before calling
kmemdup().
Signed-off-by: NXiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

If LOG_DEVICE is defined and map->dev is NULL it will lead to NULL
pointer dereference. This patch fixes this issue by adding check for
dev->NULL in all such places in regmap.c
Signed-off-by: NPankaj Dubey <pankaj.dubey@samsung.com>
Signed-off-by: NMark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

Recents commits for getting reg endianness causing NULL pointer
dereference if dev is passed NULL in regmap_init_mmio. This patch
fixes this issue, and allows to parse reg endianness only if dev
and dev->of_node exist.
Signed-off-by: NPankaj Dubey <pankaj.dubey@samsung.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Split regmap_get_endian() in two functions, regmap_get_reg_endian() and
regmap_get_val_endian().

This allows to:
  - Get rid of the three switch()es on "type", incl. error handling in
    three "default" cases,
  - Get rid of the regmap_endian_type enum,
  - Get rid of the non-NULL check of "config" (regmap_init() already
    checks for that),
  - Get rid of the "endian" output parameters, and just return the
    regmap_endian enum value, as the functions can no longer fail.

This saves 21 lines of code (despite the still-present
one-comment-per-line over-documentation), and 30 bytes of code on ARM
V7.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

A previous over-zealous factorisation of code means that we only treat
registers as volatile if they are readable. For most devices this is fine
since normally most registers can be read and volatility implies
readability but for format_write() devices where there is no readback from
the hardware and we use volatility to mean simply uncacheability this means
that we end up treating all registers as cacheble.

A bigger refactoring of the code to clarify this is in order but as a fix
make a minimal change and only check readability when checking volatility
if there is no format_write() operation defined for the device.
Signed-off-by: NMark Brown <broonie@linaro.org>
Tested-by: NLars-Peter Clausen <lars@metafoo.de>
Cc: stable@vger.kernel.org

Commit d647c199 ("regmap: add DT endianness binding support") had
some issues. Commit ba1b53fe ("regmap: Fix DT endianess parsing
logic") fixed the main problem. This patch fixes the other.

Specifically, restore the overall default of REGMAP_ENDIAN_BIG if none of
the config, DT, or the bus specify any endianness. Without this,
of_regmap_get_endian() could return REGMAP_ENDIAN_DEFAULT, which the
calling code can't handle. Since all busses do specify an endianness in
the current code, this makes no difference right now, but I saw no
justification in the patch description for removing this final default.

Also, clean up the code a bit:

* s/of_regmap_get_endian/regmap_get_endian/ since the function isn't DT-
  specific, even if the reason it was originally added was to add some
  DT-specific features.
* After potentially reading an endianess specification from DT, the code
  checks whether DT did specify an endianness, and if so, returns it. Move
  this test outside the whole switch statement so that if the
  REGMAP_ENDIAN_REG case ever modifies *endian, this check will pick that
  up. This partially reverts part of commit ba1b53fe ("regmap: Fix DT
  endianess parsing logic"), while maintaining the bug-fix that commit
  made to this code.
* Make the comments briefer, and only refer to the specific action taken
  at their location. This makes most of the comments independent of DT,
  and easier to follow.

Cc: Xiubo Li <Li.Xiubo@freescale.com>
Cc: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Cc: Thierry Reding <treding@nvidia.com>
Fixes: d647c199 ("regmap: add DT endianness binding support")
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Commit d647c199 ("regmap: add DT endianness binding support.")
added support to parse the device endianness from the device tree
but unfortunately the added logic doesn't have the same semantics
than the old code. This leads to a NULL dereference pointer error
when these properties are not provided by the Device Tree:

Unable to handle kernel NULL pointer dereference at virtual address 00000044
pgd = c0004000
[00000044] *pgd=00000000
Internal error: Oops: 5 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 5 PID: 1 Comm: swapper/0 Not tainted 3.17.0-rc1-next-20140818ccu #671
task: ea412800 ti: ea484000 task.ti: ea484000
PC is at regmap_update_bits+0xc/0x5c

The problem is that platforms that rely on the default value now
gets different values due two related issues in the current code:

a) It only parses the endianness from DT for the regmap registers
   and not for the regmap values but it checks unconditionally in
   both cases if the resulting endiannes is REGMAP_ENDIAN_NATIVE.

b) REGMAP_ENDIAN_NATIVE is not even a valid DT property according
   to the regmap DT binding documentation so it shouldn't be set.
Signed-off-by: NJavier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: NMark Brown <broonie@linaro.org>

For many drivers which will support rich endianness of Devices
need define DT properties by itself with the binding support.

The endianness using regmap:
Index      Device     Properties if needs bytes-swap,
                      or just ignore it
-------------------------------------------------------------
1          BE         'big-endian'
2          LE         'little-endian'

The properties include all the register values and the buffers.
And these properties are very usful for the MMIO devices:

Such as: a memory-mapped device, on one SoC is in BE mode, while
in another SoC will be in LE mode, and the CPU will always in LE
mode.

For the first case, we must use cpu_to_be32/be32_to_cpu for
32-bit registers accessing, so the 'big-endian' property is needed.

For the second case, we can just ignore the bytes-swap
functions like cpu_to_le32/le32_to_cpu, so the 'little-endian'
property could be abscent.

And vice versa...
Signed-off-by: NXiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Signed-off-by: NMark Brown <broonie@linaro.org>

Add a new function regmap_get_device to obtain the underlying struct
device from a regmap.
Signed-off-by: NTuomas Tynkkynen <ttynkkynen@nvidia.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

drivers/base/regmap/regmap.c: In function ‘_regmap_range_multi_paged_reg_write’:
drivers/base/regmap/regmap.c:1665: warning: ‘this_page’ may be used uninitialized in this function
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NMark Brown <broonie@linaro.org>

Since we cannot make sure the 'len = pair_size * num_regs' will always
be none zero from the users, and then if 'num_regs' equals to zero by
mistake or other reasons, the kzalloc() will return ZERO_SIZE_PTR, which
equals to ((void *)16).

So this patch fix this with just doing the 'len' zero check before calling
kzalloc().
Signed-off-by: NXiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Some busses do not support sending/receiving multiple registers in one go.
Such kind of busses just unpack the registers that have been previously
packed by the regmap core or pack registers that will be later unpacked by
the core code.

Add reg_write and reg_read callbacks in order to optimize access through
this kind of busses.
Signed-off-by: NBoris BREZILLON <boris.brezillon@free-electrons.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Allow busses to request little endianness formatting and
parsing for 16- and 32-bit values. This will be useful to
support regmap-mmio.

For the following the scenarios using the regmap-mmio,
for example:

Index    CPU       Device     Endianess flag for values
----------------------------------------------------------
1        LE        LE         REGMAP_ENDIAN_DEFAULT/NATIVE
2        LE        BE         REGMAP_ENDIAN_BIG
3        BE        BE         REGMAP_ENDIAN_DEFAULT/NATIVE
4        BE        LE         REGMAP_ENDIAN_LITTLE

For one device driver, which will support all the cases above,
needs two boolean properties in DT node like: 'big-endian'
for case 2 and 'little-endian' for case 4, and for cases 1
and 3 they all will be absent.
Signed-off-by: NXiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

It need to add curly braces because the inner for "if" has
two statements.

coccicheck says:
 drivers/base/regmap/regmap.c:765:2-44:
code aligned with following code on line 766
Signed-off-by: NDaeseok Youn <daeseok.youn@gmail.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

regmap deploys the spinlock for the protection when set up in fast_io
mode.  This may lead to sleep-in-atomic by memory allocation with
GFP_KERNEL in regmap_bulk_write().  This patch fixes it by moving the
allocation out of the lock.

[Fix excessively large locked region -- broonie]
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NMark Brown <broonie@linaro.org>

With fast_io we use mutexes to lock the I/O operations so we would need
to do GFP_ATOMIC allocations if we wanted to do allocations inside the
lock as we do currently. Since it is unlikely that we will want to register
a patch outside of init where concurrency shouldn't be an issue move the
allocation of the patch data outside the lock.
Reported-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NMark Brown <broonie@linaro.org>

This is the implementation of regmap_multi_reg_write()

There is a new capability 'can_multi_write' that device drivers
must set in order to use this multi reg write mode.

This replaces the first definition, which just defined the API.
Signed-off-by: NAnthony Olech <anthony.olech.opensource@diasemi.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

    In some cases, we need regmap's format parse_val function
to do be/le translation according to the bus configuration.
For example, snd_soc_bytes_put() uses regmap to write/read values,
and use cpu_to_be() directly to covert MASK into big endian. This
is a defect, and should use regmap's format function to do it according
to bus configuration.
Signed-off-by: NNenghua Cao <nhcao@marvell.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Since we now have an internal version of regmap_multi_reg_write use this
to apply the register patch.
Signed-off-by: NCharles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Devices with more complex boot proceedures may occasionally apply the
register patch manual. regmap_multi_reg_write is a logical way to do so,
however the patch must be applied with cache bypass on, such that it
doesn't override any user settings. This patch adds a
regmap_multi_reg_write_bypassed function that applies a set of writes
with the bypass enabled.
Signed-off-by: NCharles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

There should be no need for the writes supplied to this function to be
edited by it so mark them as const.
Signed-off-by: NCharles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

   /drivers/base/regmap/regmap.c:717:6-33: WARNING:
Comparison to bool.

   More information about semantic patching is available at
http://coccinelle.lip6.fr/Signed-off-by: NNenghua Cao <nhcao@marvell.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Currently, we check the registers in the patch are aligned to the
register stride everytime we sync the cache and the first time the patch
is written out is unchecked.

This patch checks the register patch when we first register it so the
first writes are no longer unchecked and then doesn't check on
subsequent syncs as the patch will be unchanged.
Signed-off-by: NCharles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Since sometimes the 'config' parameter has no use, it should be NULL.
And make the code simplifier.
Signed-off-by: NXiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Create special function regmap_attach_dev
which can be called separately out of regmap_init.
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

Check if regs are readable.
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

regmap_bulk_write() should decay to performing individual writes
if we're using a "no-bus" regmap. Unfortunately, it returns an
error because there is no map->bus pointer. Fix it.
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NMark Brown <broonie@linaro.org>

regmap_bulk_read() should decay to performing individual reads if
we're using a "no-bus" regmap. Unfortunately, it returns an
error because there is no map->bus pointer. Fix it.
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NMark Brown <broonie@linaro.org>