According to the i.mx spec, for multimaster mode, if I2C is
enabled when the bus is busy and asserts start, hardware inhibits
the transmission, clears MSTA without signaling a stop, generate
an interrupt, and set I2C_I2SR[IAL] to indicate a failed attempt
to engage the bus, which means arbitration lost. In this case,
we should first test I2C_I2SR[IAL], and clear this bit if it is
set, and then I2C controller default to slave receive mode.

This patch check the IAL bit every time before an I2c transmission.
if IAL is set, clear it and make I2C controller to default mode.
Signed-off-by: NHaibo Chen <haibo.chen@freescale.com>
Acked-by: NFugang Duan <B38611@freescale.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Having a transfer more than 32 bits is not all that unlikely.  Remove
the annotation.

The unlikely in the IRQ handler can't gain us much.  It's not in a
loop, so at most it would save 1 instruction per IRQ, which isn't
much.  In fact on the compiler I tested it produced the exact same
code.  Remove it too.
Suggested-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: NDoug Anderson <dianders@chromium.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Check if the ICMSR register (masked with the ICMIER register) evaluates to 0  in
the driver's interrupt handler and return IRQ_NONE in that case, like many other
drivers do.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

rcar_i2c_prepare_msg() always returns 0, so we can make this function return
*void* and thus remove the result check in rcar_i2c_master_xfer().
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

rcar_i2c_master_xfer() needlessly compares the message pointers (using indirect
addressing) in order to detect the last I2C message, while it's enough to only
compare the message indexes.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Use the platform data to set the clk_freq when there is no DT configuration
available. The clk_freq in turn will determine the I2C speed mode.

In Quark, there is currently no other configuration mechanism other than
board files.
Signed-off-by: NRaymond Tan <raymond.tan@intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: NHock Leong Kweh <hock.leong.kweh@intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Some legacy devices support ony I2C standard mode at 100kHz.
This patch allows to select the standard mode through the DTS
with the use of the existing clock-frequency parameter.

When clock-frequency parameter is not set, the fast mode is selected.
Only when the parameter is set at 100000, the standard mode is selected.
Signed-off-by: NRomain Baeriswyl <romainba@abilis.com>
Reviewed-by: NChristian Ruppert <christian.ruppert@abilis.com>
Acked-by: NAlan Tull <atull@opensource.altera.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

If adapter->dev.parent == NULL there is a NULL pointer dereference in
acpi_i2c_install_space_handler and acpi_i2c_remove_space_handler.

This is present since introduction of this code:
36604751 "i2c: rework kernel config I2C_ACPI" or even
da3c6647 "I2C/ACPI: Clean up I2C ACPI code and Add CONFIG_I2C_ACPI"

The adapter->dev.parent == NULL case is valid for the i2c_stub,
so loading i2c_stub with ACPI_I2C_OPREGION enabled results in an oops.
This is also valid at least for i2c_tiny_usb and i2c_robotfuzz_osif.

Fix by checking whether it is null before calling ACPI_HANDLE.
Signed-off-by: NPeter Huewe <peterhuewe@gmx.de>
Acked-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Commit 5d98e61d ("I2C/ACPI: Add i2c ACPI operation region support")
renamed the i2c-core module. This may cause regressions for
distributions, so put the ACPI code back into the core.
Reported-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Tested-by: NLan Tianyu <tianyu.lan@intel.com>
Tested-by: NMika Westerberg <mika.westerberg@linux.intel.com>

I2C_CLKDIV register descripted in the previous version of
RK3x chip manual is incorrect. Plus 1 is required.

The correct formula:
- T(SCL_HIGH) = T(PCLK) * (CLKDIVH + 1) * 8
- T(SCL_LOW) = T(PCLK) * (CLKDIVL + 1) * 8
- (SCL Divsor) = 8 * ((CLKDIVL + 1) + (CLKDIVH + 1))
- SCL = PCLK / (CLK Divsor)

It will be updated to the latest version of chip manual.
Signed-off-by: NAddy Ke <addy.ke@rock-chips.com>
Reviewed-by: NDoug Anderson <dianders@chromium.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

If I2C_M_RD flag is set SELECT command is sent and afterward READ
command. The patch fixes READ command to return READ failure error
message instead of SELECT failure error message.
Signed-off-by: NJanusz Uzycki <j.uzycki@elproma.com.pl>
Acked-by: NMarek Vasut <marex@denx.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

In block write mode, when encapsulating dma_buffer, first element is
'command', the rest is data buffer, so only copy actual data buffer
starting from block[1] with the size indicating by block[0].
Signed-off-by: NFan Du <fan.du@intel.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

Bits 8-31 of all registers reflect the value of bits 0-7 on reads and should be
0 on writes, according to the manuals. RCAR_IRQ_ACK_{RECV|SEND} macros have all
1's in bits 8-31, thus going against the manuals, so fix them.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Cc: stable@vger.kernel.org
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Currently the i2c-tegra bus driver prepares, enables
and set_rates its clocks separately for each transfer.
This causes locking problems when doing I2C transfers
from clock notifiers; see
http://lists.infradead.org/pipermail/linux-arm-kernel/2014-July/268653.html

This patch moves clk_prepare/unprepare and clk_set_rate calls to
the probe function, leaving only clk_enable/disable to be
done on each transfer. This solves the locking issue.
Signed-off-by: NMikko Perttunen <mperttunen@nvidia.com>
Reviewed-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This reverts commit 150b8be3.

The I2C core's per-adapter locks can't protect from IRQs, so the driver still
needs a spinlock to protect the register accesses.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Cc: stable@vger.kernel.org # 3.16+
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The driver was not bound checking the received length byte to ensure it was within the
the buffer size that is allocated for SMBus blocks. This resulted in buffer overflows
whenever an invalid length byte was received.
It also failed to ensure the length byte was not zero. If it received zero, it would end up
in an infinite loop as the at91_twi_read_next_byte function returned immediately without
allowing RHR to be read to clear the RXRDY interrupt.

Tested agaisnt a SMBus compliant battery.
Signed-off-by: NMarek Roszko <mark.roszko@gmail.com>
Acked-by: NLudovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

In rk3x SOC, the I2C controller can receive/transmit up to 32 bytes data
in one chunk, so the size of data to be write/read to/from TXDATAx/RXDATAx
must be less than or equal 32 bytes at a time.

Tested on rk3288-pinky board, elan receive 158 bytes data.
Signed-off-by: NAddy Ke <addy.ke@rock-chips.com>
Acked-by: NMax Schwarz <max.schwarz@online.de>
Reviewed-by: NDoug Anderson <dianders@chromium.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

There is a race condition in at91_do_twi_xfer when signals arrive.
If a signal is recieved while waiting for a transfer to complete
wait_for_completion_interruptible_timeout() will return -ERESTARTSYS.
This is not handled correctly resulting in interrupts still being
enabled and a transfer being in flight when we return.

Symptoms include a range of oopses and bus lockups. Oopses can happen
when the transfer completes because the interrupt handler will corrupt
the stack. If a new transfer is started before the interrupt fires
the controller will start a new transfer in the middle of the old one,
resulting in confused slaves and a locked bus.

To avoid this, use wait_for_completion_io_timeout instead so that we
don't have to deal with gracefully shutting down the transfer and
disabling the interrupts.
Signed-off-by: NSimon Lindgren <simon@aqwary.com>
Acked-by: NLudovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

The "clock-frequency" DT property is listed as optional, However,
the current code stores the return value of of_property_read_u32 in
the return code of mv64xxx_of_config, but then forgets to clear it
after setting the default value of "clock-frequency". It is then
passed out to the main probe function, resulting in a probe failure
when "clock-frequency" is missing.

This patch checks and then throws away the return value of
of_property_read_u32, instead of storing it and having to clear it
afterwards.

This issue was discovered after the property was removed from all
sunxi DTs.

Fixes: 4c730a06 ("i2c: mv64xxx: Set bus frequency to 100kHz if clock-frequency is not provided")
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Cc: stable@vger.kernel.org
Acked-by: NAndrew Lunn <andrew@lunn.ch>
Acked-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Sometimes the MNR and MST interrupts happen simultaneously  (stop  automatically
follows NACK, according to the manuals) and in such case the ID_NACK flag  isn't
set since the MST interrupt handling precedes MNR and all interrupts are cleared
and disabled then, so that MNR interrupt is never noticed -- this causes NACK'ed
transfers to be falsely reported as successful. Exchanging MNR and  MST handlers
fixes this issue, however the MNR bit  somehow  gets set again even after  being
explicitly cleared, so I decided to completely suppress handling of all disabled
interrupts (which is a good thing anyway)...
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Cc: stable@vger.kernel.org
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The SMBus host controller is the same as used in Baytrail so add the new
PCI ID to the driver's list of supported IDs.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Commit da3c6647(I2C/ACPI: Clean up I2C ACPI code and Add CONFIG_I2C_ACPI
config) adds a new kernel config I2C_ACPI and make I2C core built in
when the config is selected. This is wrong because distributions
etc generally compile I2C as a module and the commit broken that.
This patch is to rename I2C_ACPI to ACPI_I2C_OPREGION. New config
only controls ACPI I2C operation region code and depends on I2C=y.
Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
[wsa: removed unrelated change for Kconfig]
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Of_node_put supports NULL as its argument, so the initial test is not
necessary.

Suggested by Uwe Kleine-König.

The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression e;
@@

-if (e)
   of_node_put(e);
// </smpl>
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

If slave holds scl, I2C_IPD[7] will be set 1 by controller
for debugging. Driver must ignore it.

[    5.752391] rk3x-i2c ff160000.i2c: unexpected irq in WRITE: 0x80
[    5.939027] rk3x-i2c ff160000.i2c: timeout, ipd: 0x80, state: 4
Signed-off-by: NAddy Ke <addy.ke@rock-chips.com>
Reviewed-by: NHeiko Stuebner <heiko@sntech.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

Fixes the following by using %pR:

drivers/i2c/busses/i2c-imx.c: In function i2c_imx_probe()
drivers/i2c/busses/i2c-imx.c:689:2: warning: format 0x%x expects argument
of type unsigned int, but argument 4 has type resource_size_t [-Wformat=]
  dev_dbg(&i2c_imx->adapter.dev, "device resources from 0x%x to 0x%x\n",
  ^
...
Signed-off-by: NXiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This fixes a error handling scenario where clocks were not being disabled
when QUP_OUTPUT_BLOCK_SIZE returns a size greater than the size of blk_sizes
array. So this patch adds a statement to jump to the fail lable to release the
clocks.
Signed-off-by: NPramod Gurav <pramod.gurav@smartplayin.com>
Acked-by: NIvan T. Ivanov <iivanov@mm-sol.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

All Exynos5 platforms have HSI2C controllers and are needed by
various IPs connected to the boards based on these SoCs. Thus
select this by default for Exynos5 platforms.
Signed-off-by: NSachin Kamat <sachin.kamat@samsung.com>
Acked-by: NKukjin Kim <kgene.kim@samsung.com>
Reviewed-by: NDoug Anderson <dianders@chromium.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This may appear as PCI or ACPI depending upon the firmware so we
have to list both. All share the same ACPI identifier but not
the same PCI identifier.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Commit a0682a31 ("i2c: gpio: Use devm_gpio_request()") left unused
code behind, clean it up.

Fixes: a0682a31 ("i2c: gpio: Use devm_gpio_request()")
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

pca954x may be power lost during suspend, so after resume we also suffer
the issue fixed by commit cd823db8,

 "pca954x power-on default is channel 0 connected. If multiple pca954x
 muxes are connected to the same physical I2C bus, the parent bus will
 see channel 0 devices behind both muxes by default."

What's more, when resume bootloader may also operate the mux, so the
the channel connected after that may not be the one driver thought.

We fix this problem by putting the mux to disconnected state and
clearing last_chan in the resume hook.
Signed-off-by: NJisheng Zhang <jszhang@marvell.com>
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The i2c timing values specified in the driver are the minimun values
defined in the I2C specifications. The I2C specification does not
specify any default or maximum values.

Some I2C devices are out of spec, such as the HDMI link of the Toshiba
19AV600 TV, and might not work properly with minimum values.

This patch adds a 10% margin on all the timings in both Normal and Fast modes.

Trial and error method have been used to find the minimum margin necessary to
have the out-of-spec device working, and a security margin has been added.
Signed-off-by: NMaxime Coquelin <maxime.coquelin@st.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

dma_{un}map_* uses 'enum dma_data_direction' not 'enum dma_transfer_direction'.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Acked-by: NLudovic Desroches <ludovic.desroches@atmel.com>
Cc: stable@kernel.org

When building multi_v7_defconfig with CONFIG_ARM_LPAE=y the following warning
is seen:

drivers/i2c/busses/i2c-st.c:818:2: warning: format '%x' expects argument of type
'unsigned int', but argument 4 has type 'resource_size_t' [-Wformat=]

Use %pa to print 'resource_size_t' type to fix the warning.
Reported-by: NOlof's autobuilder <build@lixom.net>
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Acked-by: NMaxime Coquelin <maxime.coquelin@st.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

When the wake-up is triggered by the PMIC RTC, the RTC driver is trying
to read the PMIC interrupt status over I2C and fails because the I2C
controller is not resumed yet.
Let's resume the I2C controller earlier in the _noirq phase
(as other hardwares are doing), so we can properly get the wake-up
condition.

[tomasz: Also fixes certain issues on Exynos4-based boards.]
Signed-off-by: NVincent Palatin <vpalatin@chromium.org>
Signed-off-by: NDoug Anderson <dianders@chromium.org>
Reviewed-by: NJavier Martinez Canillas <javier.martinez@collabora.co.uk>
Acked-by: NTomasz Figa <t.figa@samsung.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This patch adds helper functions to configure clock parents and rates
as specified through 'assigned-clock-parents', 'assigned-clock-rates'
DT properties for a clock provider or clock consumer device.
The helpers are now being called by the bus code for the platform, I2C
and SPI busses, before the driver probing and also in the clock core
after registration of a clock provider.
Signed-off-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Acked-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NMike Turquette <mturquette@linaro.org>

I2C block transfers can have a size up to 32 bytes. If starting close
to the end of the address space, there may not be enough room to write
that many bytes (on I2C block writes) or not enough bytes to be read
(on I2C block reads.) In that case, we must shorten the transfer so
that it does not exceed the address space.
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Reviewed-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Signed-off-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

A long name broke the alignment, shift the columns a bit to fix it and
make the table look nice again. While we're here, switch to the
standard comment style to make checkpatch happy, and use tabs instead
of spaces for column alignment.
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Some chips implement banked register ranges. This allows implementing
more registers than the limited 8-bit address space originally allows.
In order to access a register on these chips, you must first select
the proper bank. Add support for this mechanism to the i2c-stub driver
so that such chips can be emulated. All the bank settings are passed
as module parameters.
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Tested-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This makes initialization, cleanup and look-up easier.
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Reviewed-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>