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Pull i2c updates from Wolfram Sang:
"Here is the pull request from the i2c subsystem. It got a little
delayed because I needed to wait for a dependency to be included
(commit b424080a9e08: "reset: Add optional resets and stubs"). Plus,
I had some email problems. All done now, the highlights are:
- drivers can now deprecate their use of i2c classes. That shouldn't
be used on embedded platforms anyhow and was often blindly
copy&pasted. This mechanism gives users time to switch away and
ultimately boot faster once the use of classes for those drivers is
gone for good.
- new drivers for QUP, Cadence, efm32
- tracepoint support for I2C and SMBus
- bigger cleanups for the mv64xxx, nomadik, and designware drivers
And the usual bugfixes, cleanups, feature additions. Most stuff has
been in linux-next for a while. Just some hot fixes and new drivers
were added a bit more recently."
* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (63 commits)
i2c: cadence: fix Kconfig dependency
i2c: Add driver for Cadence I2C controller
i2c: cadence: Document device tree bindings
Documentation: i2c: improve section about flags mangling the protocol
i2c: qup: use proper type fro clk_freq
i2c: qup: off by ones in qup_i2c_probe()
i2c: efm32: fix binding doc
MAINTAINERS: update I2C web resources
i2c: qup: New bus driver for the Qualcomm QUP I2C controller
i2c: qup: Add device tree bindings information
i2c: i2c-xiic: deprecate class based instantiation
i2c: i2c-sirf: deprecate class based instantiation
i2c: i2c-mv64xxx: deprecate class based instantiation
i2c: i2c-designware-platdrv: deprecate class based instantiation
i2c: i2c-davinci: deprecate class based instantiation
i2c: i2c-bcm2835: deprecate class based instantiation
i2c: mv64xxx: Fix reset controller handling
i2c: omap: fix usage of IS_ERR_VALUE with pm_runtime_get_sync
i2c: efm32: new bus driver
i2c: exynos5: remove unnecessary cast of void pointer
...
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If the renamed symbol is defined lib/iomap.c implements ioport_map and
ioport_unmap and currently (nearly) all platforms define the port
accessor functions outb/inb and friend unconditionally. So
HAS_IOPORT_MAP is the better name for this.
Consequently NO_IOPORT is renamed to NO_IOPORT_MAP.
The motivation for this change is to reintroduce a symbol HAS_IOPORT
that signals if outb/int et al are available. I will address that at
least one merge window later though to keep surprises to a minimum and
catch new introductions of (HAS|NO)_IOPORT.
The changes in this commit were done using:
$ git grep -l -E '(NO|HAS)_IOPORT' | xargs perl -p -i -e 's/\b((?:CONFIG_)?(?:NO|HAS)_IOPORT)\b/$1_MAP/'
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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During development, the driver first really needed to depend on
COMMON_CLK only. Later, it was switched to writel_relaxed, but it was
forgotten to update the dependencies, so build errors occured:
config: make ARCH=i386 allyesconfig
All error/warnings:
drivers/i2c/busses/i2c-cadence.c: In function 'cdns_i2c_clear_bus_hold':
>> drivers/i2c/busses/i2c-cadence.c:168:3: error: implicit declaration
>> of function 'writel_relaxed' [-Werror=implicit-function-declaration]
Use a very safe dependency for now.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Add a driver for the Cadence I2C controller. This controller is for
example found in Xilinx Zynq.
Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Harini Katakam <harinik@xilinx.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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It is used with of_property_read_u32(), so it should be u32.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Fixes: 10c5a8425968 ('i2c: qup: New bus driver for the Qualcomm QUP I2C controller')
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These should ">= ARRAY_SIZE()" instead of "> ARRAY_SIZE()".
Fixes: 10c5a8425968 ('i2c: qup: New bus driver for the Qualcomm QUP I2C controller')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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This bus driver supports the QUP i2c hardware controller in the Qualcomm SOCs.
The Qualcomm Universal Peripheral Engine (QUP) is a general purpose data path
engine with input/output FIFOs and an embedded i2c mini-core. The driver
supports FIFO mode (for low bandwidth applications) and block mode (interrupt
generated for each block-size data transfer).
Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Reviewed-by: Andy Gross <agross@codeaurora.org>
Tested-by: Philip Elcan <pelcan@codeaurora.org>
[wsa: removed needless IS_ERR_VALUE]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Warn users that class based instantiation is going away soon in favour
of more robust probing and faster bootup times.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Warn users that class based instantiation is going away soon in favour
of more robust probing and faster bootup times.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: Barry Song <baohua@kernel.org>
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Warn users that class based instantiation is going away soon in favour
of more robust probing and faster bootup times.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Warn users that class based instantiation is going away soon in favour
of more robust probing and faster bootup times.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Warn users that class based instantiation is going away soon in favour
of more robust probing and faster bootup times.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: Sekhar Nori <nsekhar@ti.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>
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Warn users that class based instantiation is going away soon in favour
of more robust probing and faster bootup times.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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The reset framework recently gained optional stubs when CONFIG_RESET_CONTROLLER
is not selected. It also introduced a function reset_get_optional, that is also
dummy-defined whenever the framework isn't enabled, for drivers that needs an
optional reset controller.
Switch to this function, since the mv64xxx driver is in this case. This also
fixes a compilation breakage whenever the reset framework wasn't selected:
drivers/i2c/busses/i2c-mv64xxx.c:771:2: error: implicit declaration of function 'devm_reset_control_get'
While we're at it, remove the redundant test on dev.of_node surrounding the
calls to reset framework functions, since it will either be a valid pointer, an
error pointer in the case where we called reset_get_optional without an of_node
pointer or if it failed, or NULL if we're not loaded through DT.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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we use IS_ERR_VALUE to check for error values of pm_runtime_get_sync,
when the value can only be < 0 in the case of err. Replace the
check with a simpler < 0 check.
This fixes the coccicheck warnings:
linux-2.6/drivers/i2c/busses/i2c-omap.c:1157:5-24:
pm_runtime_get_sync returns < 0 as error. Unecessary IS_ERR_VALUE at
line 1158
linux-2.6/drivers/i2c/busses/i2c-omap.c:1278:7-26:
pm_runtime_get_sync returns < 0 as error. Unecessary IS_ERR_VALUE at
line 1279
drivers/i2c/busses/i2c-omap.c:638:5-24:
pm_runtime_get_sync returns < 0 as error. Unecessary IS_ERR_VALUE at
line 639
Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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This was tested on a EFM32GG-DK3750 devboard that has a temperature
sensor and an eeprom on its i2c bus.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Fixes a build break due to the undeclared use of irq_of_parse_and_map()
and of_iomap(). This build break was apparently introduced while the
driver was unbuildable due to the bug fixed by
62c19c9d29e65086e5ae76df371ed2e6b23f00cd ("i2c: Remove usage of
orphaned symbol OF_I2C"). When 62c19c was added in v3.14-rc7,
the driver was enabled again, breaking the powerpc mpc85xx_defconfig
and mpc85xx_smp_defconfig.
62c19c is marked for stable, so this should go there as well.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
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The symbol is an orphan, don't depend on it anymore.
Signed-off-by: Richard Weinberger <richard@nod.at>
[wsa: enhanced commit message]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fixes: 687b81d083c0 (i2c: move OF helpers into the core)
Cc: stable@kernel.org
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Remove unnecessary cast of void pointer, because 'algo_data' of
'struct i2c_adapter' is a void pointer. Casting the void pointer
is redundant. The conversion from void pointer to any other
pointer type is guaranteed by the C programming language.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Reviewed-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Add CONFIG_PM_SLEEP to suspend/resume functions to fix the following
build warning when CONFIG_PM_SLEEP is not selected. This is because
sleep PM callbacks defined by SIMPLE_DEV_PM_OPS are only used when
the CONFIG_PM_SLEEP is enabled.
warning: 'exynos5_i2c_suspend_noirq' defined but not used [-Wunused-function]
warning: 'exynos5_i2c_resume_noirq' defined but not used [-Wunused-function]
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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When using device-tree and the i2c-gpio driver is called before the
GPIO node has been probed then it needs to correctly defer the probe
instead of returning a permanent error that the gpio numbers are not
valid.
This fixes the following error:
/i2c@2: invalid GPIO pins, sda=-517/scl=-517
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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The SMBUS tracepoints can be enabled thusly:
echo 1 >/sys/kernel/debug/tracing/events/i2c/enable
and will dump messages that can be viewed in /sys/kernel/debug/tracing/trace
that look like:
... smbus_read: i2c-0 a=051 f=0000 c=fa BYTE_DATA
... smbus_reply: i2c-0 a=051 f=0000 c=fa BYTE_DATA l=1 [39]
... smbus_result: i2c-0 a=051 f=0000 c=fa BYTE_DATA rd res=0
formatted as:
i2c-<adapter-nr>
a=<addr>
f=<flags>
c=<command>
<protocol-name>
<rd|wr>
res=<result>
l=<data-len>
[<data-block>]
The adapters to be traced can be selected by something like:
echo adapter_nr==1 >/sys/kernel/debug/tracing/events/i2c/filter
Note that this shares the same filter and enablement as i2c.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Add tracepoints into the I2C message transfer function to retrieve the message
sent or received. The following config options must be turned on to make use
of the facility:
CONFIG_FTRACE
CONFIG_ENABLE_DEFAULT_TRACERS
The I2C tracepoint can be enabled thusly:
echo 1 >/sys/kernel/debug/tracing/events/i2c/enable
and will dump messages that can be viewed in /sys/kernel/debug/tracing/trace
that look like:
... i2c_write: i2c-5 #0 a=044 f=0000 l=2 [02-14]
... i2c_read: i2c-5 #1 a=044 f=0001 l=4
... i2c_reply: i2c-5 #1 a=044 f=0001 l=4 [33-00-00-00]
... i2c_result: i2c-5 n=2 ret=2
formatted as:
i2c-<adapter-nr>
#<message-array-index>
a=<addr>
f=<flags>
l=<datalen>
n=<message-array-size>
ret=<result>
[<data>]
The operation is done between the i2c_write/i2c_read lines and the i2c_reply
and i2c_result lines so that if the hardware hangs, the trace buffer can be
consulted to determine the problematic operation.
The adapters to be traced can be selected by something like:
echo adapter_nr==1 >/sys/kernel/debug/tracing/events/i2c/filter
These changes are based on code from Steven Rostedt.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
[wsa: adapted path for 'enable' in the commit msg]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Don't use DEFINE_PCI_DEVICE_TABLE macro, because this macro
is not preferred.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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There is a rather odd feature of the exynos i2c controller that if it
is left enabled, it can lock itself up with the clk line held low.
This makes the bus unusable.
Unfortunately, the s3c24xx_i2c_set_master() function does not notice
this, and reports a timeout. From then on the bus cannot be used until
the AP is rebooted.
The problem happens when any sort of interrupt occurs (e.g. due to a
bus transition) when we are not in the middle of a transaction. We
have seen many instances of this when U-Boot leaves the bus apparently
happy, but Linux cannot access it.
The current code is therefore pretty fragile.
This fixes things by leaving the bus disabled unless we are actually
in a transaction. We enable the bus at the start of the transaction and
disable it at the end. That way we won't get interrupts and will not
lock up the bus.
It might be possible to clear pending interrupts on start-up, but this
seems to be a more robust solution. We can't service interrupts when
we are not in a transaction, and anyway would rather not lock up the
bus while we try.
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Warn users that class based instantiation is going away soon in favour
of more robust probing and faster bootup times.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
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This adds the ability to set "clock-frequency" in the device tree for the at91
i2cbus following the naming of other i2c bus implementations. If the property
is not set,the clock frequency will default to the previously used define
of 100KHz.
Signed-off-by: Marek Roszko <mark.roszko@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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On Intel BayTrail, there was case whereby the resulting fast mode
bus speed becomes slower (~20% slower compared to expected speed)
if using the HCNT/LCNT calculated in the core layer. Thus, this
patch is added to allow pci glue layer to pass in optimal
HCNT/LCNT/SDA hold time values to core layer since the core
layer supports cofigurable HCNT/LCNT/SDA hold time values now.
Signed-off-by: Chew, Chiau Ee <chiau.ee.chew@intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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This patch fixes the error returned to the i2c_transfer function
to -EAGAIN in case of arbitratin lost, so that the retry mechanism
can be used.
Signed-off-by: Maxime Coquelin <maxime.coquelin@st.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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We now have a central place to put this code to.
Tested-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Calling the state machine with a definite state which is only used in
this context is superfluous. Do it directly.
Tested-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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For start and restart, we are doing the same thing. Let's consolidate
that.
Tested-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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All the I2C controllers on Intel BayTrail LPSS subsystem able
to support 10-bit addressing mode functionality.
Signed-off-by: Chew, Chiau Ee <chiau.ee.chew@intel.com>
Signed-off-by: Ong, Boon Leong <boon.leong.ong@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Use devm_ioremap_resource() in order to make the code simpler,
and remove redundant return value check of platform_get_resource()
because the value is checked by devm_ioremap_resource().
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Use devm_ioremap_resource() in order to make the code simpler,
and remove redundant return value check of platform_get_resource()
because the value is checked by devm_ioremap_resource().
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Add Device ID of Intel BayTrail SMBus Controller.
Signed-off-by: Chew, Kean ho <kean.ho.chew@intel.com>
Signed-off-by: Chew, Chiau Ee <chiau.ee.chew@intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Intel Baytrail I2C controllers can be enumerated from PCI as well as from
ACPI. In order to support this add the Baytrail PCI IDs to the driver.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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The PCI part of the DesignWare I2C driver does a lot of things that are not
required anymore. For example drivers aren't supposed to handle PCI state
transitions themselves. This is all provided by the PCI bus core already.
In addition to that there is no point scheduling RPM suspend on driver's
idle hook but instead we can use RPM autosuspend for this (which is enabled
in the driver already).
As a bonus, this patch also fixes following compile warning which is
emitted when the driver was compiled without CONFIG_PM_RUNTIME set:
drivers/i2c/busses/i2c-designware-pcidrv.c:245:12: warning: ‘i2c_dw_pci_runtime_idle’ defined but not used [-Wunused-function]
Reported-by: xinhui.pan <xinhuix.pan@intel.com>
Reported-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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This patch allows to set independantly SCL and SDA falling times.
The tLOW period is computed by taking into account the SCL falling time.
The tHIGH period is computed by taking into account the SDA falling time.
For instance in case the margin on tLOW is considered too small, it can
be increased by increasing the SCL falling time which is by default set
at 300ns.
The same applies for tHIGH period with the help of SDA falling time.
Signed-off-by: Romain Baeriswyl <romainba@abilis.com>
Reviewed-by: Christian Ruppert <christian.ruppert@abilis.com>
Acked-by: Shinya Kuribayashi <skuribay@pobox.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Put necessary SSYNC code into blackfin twi arch header. The generic TWI
driver should not contain any architecture specific code.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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The ADI TWI peripheral is not binding to the Blackfin processor only.
The bits macros and structs should be put in the generic include header.
And update head file path in drivers accordingly.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Commit 370136bc67c3 ("i2c: mv64xxx: Add reset deassert call")
introduced:
drivers/video/Kconfig:42:error: recursive dependency detected!
ARCH_SUNXI selects RESET_CONTROLLER anyhow.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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The Allwinner A31 I2C controller is almost identical to the one used in the
other Allwinner SoCs, except for the fact that it needs to clear the interrupt
by setting the INT_FLAGS bit in the control register, instead of clearing it.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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The Allwinner A31 SoC using that IP has a reset controller maintaining
it reset unless told otherwise.
Add some optional reset support to the driver.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Warn users that class based instantiation is going away soon in favour
of more robust probing and faster bootup times.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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Warn users that class based instantiation is going away soon in favour
of more robust probing and faster bootup times.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Stephen Warren <swarren@nvidia.com>
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Warn users that class based instantiation is going away soon in favour
of more robust probing and faster bootup times.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
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Warn users that class based instantiation is going away soon in favour
of more robust probing and faster bootup times.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
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Warn users that class based instantiation is going away soon in favour
of more robust probing and faster bootup times.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
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Warn users that class based instantiation is going away soon in favour
of more robust probing and faster bootup times.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Sonic Zhang <sonic.zhang@analog.com>
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Linus Torvalds
Uwe Kleine-König
Wolfram Sang
Soren Brinkmann
Dan Carpenter
Bjorn Andersson
Maxime Ripard
Nishanth Menon
Scott Wood
Richard Weinberger
Jingoo Han
Ben Dooks
David Howells
Simon Glass
Marek Roszko
Chew, Chiau Ee
Maxime COQUELIN
Chew, Kean ho
Mika Westerberg
Romain Baeriswyl
Sonic Zhang