When converting to GPIOD, the GPIO directions of SCL/SDA have been
swapped. Fix it!

Fixes: ad36a279 ("i2c: imx: switch to using gpiod for bus recovery gpios")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

This HW is prone to races, so it needs to setup new messages in irq
context. That means we can't alloc bounce buffers if a message buffer is
not DMA safe. So, in that case, simply fall back to PIO.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

This ensures that we fall back to PIO if the message length is too small
for DMA being useful. Otherwise, we use DMA. A bounce buffer might be
applied by the helper if the original message buffer is not DMA safe.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

For all block commands, try to allocate a DMA safe buffer and mark it
accordingly. Only use the stack, if the buffers cannot be allocated.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Use the new helper to create variants of i2c_master_{send|recv} which
mark their buffers as DMA safe.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Those two functions are very similar, the only differences are that one
needs the I2C_M_RD flag for its message while the other one needs the
buffer casted to drop the const. Introduce a generic helper which allows
to specify the flags (also needed later for DMA safe variants of these
calls) and let the casting be done in the inlining functions which are
now calling the new helper function.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

One helper checks if DMA is suitable and optionally creates a bounce
buffer, if not. The other function returns the bounce buffer and makes
sure the data is properly copied back to the message.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

I2C has no requirement that the buffer of a message needs to be DMA
safe. In case it is, it can now be flagged, so drivers wishing to
do DMA can use the buffer directly.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Add fault injection capabilities to the i2c-gpio driver. When connected
to another I2C bus, it can create unusual states which the other I2C bus
master driver needs to handle. Only for debugging!
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

The designware core and platform are built as separate modules.
Export i2c_dw_prepare_clk() so it can be used by the platform
driver.

Fixes: a34a0b6d ("i2c: designware: move i2c_dw_plat_prepare_clk to common")
Signed-off-by: Phil Reid <preid@electromag.com.au>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

The correct header to include for the gpiod interface is
<linux/gpio/consumer.h>.

Fixes: 3991c5c8 ("i2c: Switch to using gpiod interface for gpio bus recovery")
Signed-off-by: Phil Reid <preid@electromag.com.au>
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

The datasheet was a bit vague, but after consultation with HW designers,
we came to the conclusion that we should set the SCP bit always when
dealing only with the ICE bit. A set SCP bit is ignored, and thus fine,
a cleared one may trigger STOP on the bus.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

We initiate STOP (or REP_START) on the second last WAIT interrupt
currently. This works fine but is not according to the datasheet which
says to do it on the last WAIT interrupt. This also simplifies the code
quite a lot, so let's do it.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Tested-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

There is no data when the first WAIT interrupt arrives. No need to read
something then.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

No need to do it manually.
Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

We can use the ternary operator for easier reading.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

ICE bit is for resetting the module. Other bits don't matter then, so we
don't need to use the iic_set_clr() function but can use iic_wr().
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Those two functions are very short and only called once. The code
becomes easier to understand if the code is directly put into the main
xfer function.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

No need to clear the interrupt registers because right after that we
disable the IP core which will reload registers with their initial
values anyhow.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Following the documentation, we initialize the HW before each START in
start_ch(). No need to do the same in activate_ch().
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Remove all reference to code related to using integer based ids for
scl/sda gpio for bus recovery. All in tree drivers are now using the
gpio descriptors to specific the required gpios.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Phil Reid <preid@electromag.com.au>
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Change the driver to use the gpio descriptors for the bus recovery
information instead of the deprecated integer interface.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Phil Reid <preid@electromag.com.au>
Reviewed-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Change the driver to use the gpio descriptors for the bus recovery
information instead of the deprecated integer interface.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

This patch contains much input from Phil Reid and has been tested
on Intel/Altera Cyclone V SOC Hardware with Altera GPIO's for the
SCL and SDA GPIO's.
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Tim Sander <tim@krieglstein.org>
Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

For consistency with the rest of the file rename function and parameter to
be consistent with the reset of the common file.
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Move the i2c_dw_plat_prepare_clk funciton to common file in preparation
for its use also by the master driver.
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Currently the i2c gpio recovery code uses gpio integer interface
instead of the gpiod. This change switch the core code to use
the gpiod while still retaining compatibility with the gpio integer
interface. This will allow individual driver to be updated and tested
individual to switch to using the gpiod interface.
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Using the macro IS_ENABLED to check the option CONFIG_I2C=(y|m) makes
the code nicer.  No functional change.
Signed-off-by: Stefan Lengfeld <contact@stefanchrist.eu>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

According to data sheet SCL timing parameters and DW_IC_CON SPEED mode
bits are not used when operating in slave mode.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Luis Oliveira <lolivei@synopsys.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Pull ARM fixes from Russell King:

 - LPAE fixes for kernel-readonly regions

 - Fix for get_user_pages_fast on LPAE systems

 - avoid tying decompressor to a particular platform if DEBUG_LL is
   enabled

 - BUG if we attempt to return to userspace but the to-be-restored PSR
   value keeps us in privileged mode (defeating an issue that ftracetest
   found)

* 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: BUG if jumping to usermode address in kernel mode
  ARM: 8722/1: mm: make STRICT_KERNEL_RWX effective for LPAE
  ARM: 8721/1: mm: dump: check hardware RO bit for LPAE
  ARM: make decompressor debug output user selectable
  ARM: fix get_user_pages_fast

Pull irq fixes from Thomas Glexiner:

 - unbreak the irq trigger type check for legacy platforms

 - a handful fixes for ARM GIC v3/4 interrupt controllers

 - a few trivial fixes all over the place

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/matrix: Make - vs ?: Precedence explicit
  irqchip/imgpdc: Use resource_size function on resource object
  irqchip/qcom: Fix u32 comparison with value less than zero
  irqchip/exiu: Fix return value check in exiu_init()
  irqchip/gic-v3-its: Remove artificial dependency on PCI
  irqchip/gic-v4: Add forward definition of struct irq_domain_ops
  irqchip/gic-v3: pr_err() strings should end with newlines
  irqchip/s3c24xx: pr_err() strings should end with newlines
  irqchip/gic-v3: Fix ppi-partitions lookup
  irqchip/gic-v4: Clear IRQ_DISABLE_UNLAZY again if mapping fails
  genirq: Track whether the trigger type has been set

Pull misc x86 fixes from Ingo Molnar:
 - topology enumeration fixes
 - KASAN fix
 - two entry fixes (not yet the big series related to KASLR)
 - remove obsolete code
 - instruction decoder fix
 - better /dev/mem sanity checks, hopefully working better this time
 - pkeys fixes
 - two ACPI fixes
 - 5-level paging related fixes
 - UMIP fixes that should make application visible faults more debuggable
 - boot fix for weird virtualization environment

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  x86/decoder: Add new TEST instruction pattern
  x86/PCI: Remove unused HyperTransport interrupt support
  x86/umip: Fix insn_get_code_seg_params()'s return value
  x86/boot/KASLR: Remove unused variable
  x86/entry/64: Add missing irqflags tracing to native_load_gs_index()
  x86/mm/kasan: Don't use vmemmap_populate() to initialize shadow
  x86/entry/64: Fix entry_SYSCALL_64_after_hwframe() IRQ tracing
  x86/pkeys/selftests: Fix protection keys write() warning
  x86/pkeys/selftests: Rename 'si_pkey' to 'siginfo_pkey'
  x86/mpx/selftests: Fix up weird arrays
  x86/pkeys: Update documentation about availability
  x86/umip: Print a warning into the syslog if UMIP-protected instructions are used
  x86/smpboot: Fix __max_logical_packages estimate
  x86/topology: Avoid wasting 128k for package id array
  perf/x86/intel/uncore: Cache logical pkg id in uncore driver
  x86/acpi: Reduce code duplication in mp_override_legacy_irq()
  x86/acpi: Handle SCI interrupts above legacy space gracefully
  x86/boot: Fix boot failure when SMP MP-table is based at 0
  x86/mm: Limit mmap() of /dev/mem to valid physical addresses
  x86/selftests: Add test for mapping placement for 5-level paging
  ...

Pull scheduler fixes from Ingo Molnar:
 "Misc fixes: a documentation fix, a Sparse warning fix and a debugging
  fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/debug: Fix task state recording/printout
  sched/deadline: Don't use dubious signed bitfields
  sched/deadline: Fix the description of runtime accounting in the documentation

Pull perf fixes from Ingo Molnar:
 "Misc fixes: two PMU driver fixes and a memory leak fix"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Fix memory leak triggered by perf --namespace
  perf/x86/intel/uncore: Add event constraint for BDX PCU
  perf/x86/intel: Hide TSX events when RTM is not supported

Pull static key fix from Ingo Molnar:
 "Fix a boot warning related to bad init ordering of the static keys
  self-test"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  jump_label: Invoke jump_label_test() via early_initcall()

Pull objtool fixes from Ingo Molnar:
 "A handful of objtool fixes, most of them related to making the UAPI
  header-syncing warnings easier to read and easier to act upon"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tools/headers: Sync objtool UAPI header
  objtool: Fix cross-build
  objtool: Move kernel headers/code sync check to a script
  objtool: Move synced files to their original relative locations
  objtool: Make unreachable annotation inline asms explicitly volatile
  objtool: Add a comment for the unreachable annotation macros

Detect if we are returning to usermode via the normal kernel exit paths
but the saved PSR value indicates that we are in kernel mode.  This
could occur due to corrupted stack state, which has been observed with
"ftracetest".

This ensures that we catch the problem case before we get to user code.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>