Baruch reported an OOPS when using the designware controller as target
only. Target-only modes break the assumption of one transfer function
always being available. Fix this by always checking the pointer in
__i2c_transfer.

Reported-by: Baruch Siach <baruch@tkos.co.il>
Closes: https://lore.kernel.org/r/4269631780e5ba789cf1ae391eec1b959def7d99.1712761976.git.baruch@tkos.co.il
Fixes: 4b1acc43331d ("i2c: core changes for slave support")
[wsa: dropped the simplification in core-smbus to avoid theoretical regressions]
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Baruch Siach <baruch@tkos.co.il>

The function using this is hidden in an #ifdef, so the variable
needs the same one for a clean W=1 build:

drivers/i2c/busses/i2c-pxa.c:327:26: error: 'icr_bits' defined but not used [-Werror=unused-const-variable=]

Fixes: d6a7b5f84b5c ("[ARM] 4827/1: fix two warnings in drivers/i2c/busses/i2c-pxa.c")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>

Commit 857cc04cdf50 ("i2c: i801: Add helper i801_get_block_len")
introduced a slight functional change: the status variable is now
overwritten with the length of an SMBUS tranasaction,
even in case of success.

This breaks the touchpad on at least my Lenovo P1:

rmi4_physical rmi4-00: Read PDT entry at 0x00e9 failed, code: -6.
rmi4_physical rmi4-00: RMI initial reset failed! Continuing in spite of this.
rmi4_physical rmi4-00: Read PDT entry at 0x00e9 failed, code: -6.
rmi4_physical rmi4-00: IRQ counting failed with code -6.

Fixes: 857cc04cdf50 ("i2c: i801: Add helper i801_get_block_len")
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>

Some hardware designs with multiple PCA954x devices use a reset GPIO
connected to all the muxes. Support this configuration by making use of
the reset controller framework which can deal with the shared reset
GPIOs. Fall back to the old GPIO descriptor method if the reset
controller framework is not enabled.

Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Acked-by: Peter Rosin <peda@axentia.se>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

Théo adds support for the Mobileye EyeQ5-I2C in the bindings.
This patch is followed by eight commits featuring improvements to
the Nomadik controller, such as simplification of the IRQ logic,
renaming of the private data structure, more efficient use of
FIELD_PREP/GET, GENMASK, etc., better time measurement with
ktime, and more.

Pull i2c updates from Wolfram Sang:
 "Minor changes to the I2C core. Most changes are in drivers:

  The i801 and designware drivers received most of the changes,
  including refactorings and some additions.

  Recovery changes for the iMX and iMX-LPI2C are now utilizing the
  generic i2c support.

  The Cadence driver now supports system suspend and resume.

  The hisi, mpc, sh_mobile, and npcm drivers have undergone some
  cleanups and improvements. Meanwhile, Uwe continues his work on
  converting the "remove" callback to become a void function.

  The pca954x mux driver now supports additional configurations, such as
  isolating faulty channels and flushing stuck buses, among others.

  Support has been added for Renesas r8a779h0, i.MX95 LPI2C, and
  Microchip sam9x7. Meanwhile, Geert lays the groundwork for the
  upcoming R-Car Gen4"

* tag 'i2c-for-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (34 commits)
  i2c: sprd: Convert to platform remove callback returning void
  Documentation: i2c: Document that client auto-detection is a legacy mechanism
  i2c: remove redundant condition
  i2c: rcar: Prepare for the advent of ARCH_RCAR_GEN4
  i2c: imx-lpi2c: add generic GPIO recovery for LPI2C
  i2c: cadence: Add system suspend and resume PM support
  i2c: mpc: remove outdated macro
  i2c: mpc: use proper binding for transfer timeouts
  dt-bindings: i2c: mpc: use proper binding for transfer timeouts
  i2c: smbus: Prepare i2c_register_spd for usage on muxed segments
  i2c: constify the struct device_type usage
  i2c: designware: Implement generic polling mode code for Wangxun 10Gb NIC
  i2c: designware: Fix RX FIFO depth define on Wangxun 10Gb NIC
  i2c: designware: Move interrupt handling functions before i2c_dw_xfer()
  i2c: designware: Use accessors to DW_IC_INTR_MASK register
  i2c: designware: Do not enable interrupts shortly in polling mode
  i2c: designware: Uniform initialization flow for polling mode
  dt-bindings: i2c: at91: Add sam9x7 compatible string
  dt-bindings: i2c: imx-lpi2c: add i.MX95 LPI2C
  i2c: Remove redundant comparison in npcm_i2c_reg_slave
  ...

Pull non-MM updates from Andrew Morton:

 - Kuan-Wei Chiu has developed the well-named series "lib min_heap: Min
   heap optimizations".

 - Kuan-Wei Chiu has also sped up the library sorting code in the series
   "lib/sort: Optimize the number of swaps and comparisons".

 - Alexey Gladkov has added the ability for code running within an IPC
   namespace to alter its IPC and MQ limits. The series is "Allow to
   change ipc/mq sysctls inside ipc namespace".

 - Geert Uytterhoeven has contributed some dhrystone maintenance work in
   the series "lib: dhry: miscellaneous cleanups".

 - Ryusuke Konishi continues nilfs2 maintenance work in the series

	"nilfs2: eliminate kmap and kmap_atomic calls"
	"nilfs2: fix kernel bug at submit_bh_wbc()"

 - Nathan Chancellor has updated our build tools requirements in the
   series "Bump the minimum supported version of LLVM to 13.0.1".

 - Muhammad Usama Anjum continues with the selftests maintenance work in
   the series "selftests/mm: Improve run_vmtests.sh".

 - Oleg Nesterov has done some maintenance work against the signal code
   in the series "get_signal: minor cleanups and fix".

Plus the usual shower of singleton patches in various parts of the tree.
Please see the individual changelogs for details.

* tag 'mm-nonmm-stable-2024-03-14-09-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (77 commits)
  nilfs2: prevent kernel bug at submit_bh_wbc()
  nilfs2: fix failure to detect DAT corruption in btree and direct mappings
  ocfs2: enable ocfs2_listxattr for special files
  ocfs2: remove SLAB_MEM_SPREAD flag usage
  assoc_array: fix the return value in assoc_array_insert_mid_shortcut()
  buildid: use kmap_local_page()
  watchdog/core: remove sysctl handlers from public header
  nilfs2: use div64_ul() instead of do_div()
  mul_u64_u64_div_u64: increase precision by conditionally swapping a and b
  kexec: copy only happens before uchunk goes to zero
  get_signal: don't initialize ksig->info if SIGNAL_GROUP_EXIT/group_exec_task
  get_signal: hide_si_addr_tag_bits: fix the usage of uninitialized ksig
  get_signal: don't abuse ksig->info.si_signo and ksig->sig
  const_structs.checkpatch: add device_type
  Normalise "name (ad@dr)" MODULE_AUTHORs to "name <ad@dr>"
  dyndbg: replace kstrdup() + strchr() with kstrdup_and_replace()
  list: leverage list_is_head() for list_entry_is_head()
  nilfs2: MAINTAINERS: drop unreachable project mirror site
  smp: make __smp_processor_id() 0-argument macro
  fat: fix uninitialized field in nostale filehandles
  ...

Sort #include statements in i2c-nomadik driver.

Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>

Add compatible for the integration of the same DB8500 IP block into the
Mobileye EyeQ5 platform. Two quirks are present:

 - The memory bus only supports 32-bit accesses. Avoid writeb() and
   readb() by introducing helper functions that fallback to writel()
   and readl().

 - A register must be configured for the I2C speed mode; it is located
   in a shared register region called OLB. We access that memory region
   using a syscon & regmap that gets passed as a phandle (mobileye,olb).

   A two-bit enum per controller is written into the register; that
   requires us to know the global index of the I2C controller (cell arg
   to the mobileye,olb phandle).

We add #include <linux/mfd/syscon.h> and <linux/regmap.h>.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>

Allow overriding the default timeout value (200ms) from devicetree,
using the generic i2c-transfer-timeout-us property.

The i2c_adapter->timeout field is an unaccurate jiffies amount;
i2c-nomadik uses hrtimers for timeouts below one jiffy.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>