Before splitting the read/write routines into smaller, more
specialized functions, unduplicate some code in advance.

Use a 'for' loop instead of 'do while' when waiting for the previous
write to complete and hide it behind a macro.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

The first step in simplifying the read and write functions is to call
them via function pointers stored in at24_data. When we eventually
split the routines into smaller ones (depending on whether they use
smbus or i2c operations) we'll simply assign them to said pointers
instead of checking the flags at runtime every time we read/write.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Align the arguments in broken lines with the arguments list's opening
brackets and make checkpatch.pl happy by converting 'unsigned' into
'unsigned int'.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

In preparation for splitting at24_eeprom_write() & at24_eeprom_read()
into smaller, specialized routines move at24_read() below, so that it
won't be intertwined with the low-level EEPROM accessors.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

As part of the preparation for introducing support for more chips,
improve the readability of the device table by separating columns
with tabs.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

1. The current QCOM I2C driver code is failing for transfer length
greater than 255. This is happening due to improper segments length
as the I2C DMA segments can be maximum of 256 bytes.

2. The transfer length tlen was being initialized with 0 for 256
bytes, which is being passed for DMA mappings resulting in improper
DMA mapping length.

This patch fixes the above said problems by initializing the block
count with the values calculated in qup_i2c_set_blk_data and calculating
the remaining length for last DMA segment. Also, the block data length
need to be decremented after each transfer. Additionally, this patch
corrects the tlen assignment for DMA mapping.
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

1. Current QCOM I2C driver hangs when sending data to address 0x03-0x07
in some scenarios. The QUP controller generates invalid write in this
case, since these addresses are reserved for different bus formats.

2. Also, the error handling is done by I2C QUP ISR in the case of DMA
mode. The state need to be RESET in case of any error for clearing the
available data in FIFO, which otherwise leaves the BAM DMA controller
in hang state.

This patch fixes the above two issues by clearing the error bits from
I2C and QUP status in ISR in case of I2C error, QUP error and resets
the QUP state to clear the FIFO data.
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

The driver transfer to a message with NOACK always in any size.
If client (eg. EDID segment point message) needs NOACK condition, it can
use I2C_M_IGNORE_NAK flag.
Signed-off-by: Jaedon Shin <jaedon.shin@gmail.com>
Acked-by: Kamal Dasu <kdasu.kdev@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

The BCM7xxx ARM and MIPS based SoCs share a similar I2C hardware block.
Signed-off-by: Jaedon Shin <jaedon.shin@gmail.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

ACPI 5 specification doesn't have property for the I2C bus speed but
I2cSerialBus resource descriptors which define each controller-slave
connection define the maximum speed supported by that connection.

Thus finding the maximum safe speed for the bus is to walk all
I2cSerialBus resources that are associated to I2C controller and use
the speed of slowest connection.

Add function i2c_acpi_find_bus_speed() to the i2c-core that adapter
drivers can call prior registering itself to core.

This implies two-step walk through the I2cSerialBus resources: call to
i2c_acpi_find_bus_speed() does the first scan and finds the safe bus
speed that adapter drivers can set up. Adapter driver registration does
the second scan when i2c-core creates the I2C slaves by calling the
i2c_acpi_register_devices(). In that way the bus speed is set in case
slave device probe gets called during registration and does
communication.

Implement this by reusing the existing ACPI I2C walk routines in the
i2c-core. Extend them so that slowest connection speed is saved during
the walk and I2C slaves are registered only when calling through the
i2c_acpi_register_devices() with the i2c_adapter pointer.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

I2C ACPI enumeration was originally implemented in another module under
drivers/acpi/ but was later moved into i2c-core with added support for
I2C ACPI operation region.

Rename these acpi_i2c_ prefixed functions, structures and defines in
i2c-core to i2c_acpi_ in order to have more consistent name space.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Now that we revisited all error messages, we can use pr_fmt for the
remaining pr_* messages to ensure consistent output.
Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Use a warning loglevel instead of info and switch to dev_* for device
info. Also print which client was accessed.
Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Use dev_err instead of pr_err for more details.
Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Fix some whitespace issues while here.
Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Switch to WARN if no adapter name is given, otherwise we won't know who
missed to do that. Add error message if device registration fails.
Update error message for missing algo to match style of the others.
Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Move recovery init to a seperate function to let have
i2c_register_adapter() less lines and to avoid goto and a label.
Refactor string handling there for consistency and to save some bytes.
Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

On error, we should give idr back to the pool in any case.
Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Use devm_* APIs to simplify the code a bit.
This patch also fixes the memory leak when unload the module.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Tested-by: Liviu Dudau <Liviu.Dudau@arm.com>
Acked-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

There is no build dependency for this driver, so enable COMPILE_TEST to get
better build coverage.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Tested-by: Liviu Dudau <Liviu.Dudau@arm.com>
Acked-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Added ACPI support for the I2C controller present on Broadcom's
Vulcan ARM64 processor. ACPI ID used by the controller is BRCM9007.

Changed the xlp9xx_i2c_get_frequency() function to use
device_property_read_u32() API so that the "clock-frequency" value
can be read from _DSD in ACPI mode.
Signed-off-by: Tanmay Jagdale <tanmay.jagdale@broadcom.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

This driver should be buildable with COMPILE_TEST so
add this to the dependency for it.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

There is no code protecting i2c_dev to be freed after it is returned
from i2c_dev_get_by_minor() and using it to access the value which we
already have (minor) isn't safe really.

Avoid using it and get the adapter directly from 'minor'.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

There are more than 7 busses, but only 7 are user visible. Update comment
accordingly.
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

The i801 chip can handle the Host Notify feature since ICH 3 as mentioned
in http://www.intel.com/content/dam/doc/datasheet/82801ca-io-controller-hub-3-datasheet.pdf

Enable the functionality unconditionally and propagate the alert
on each notification.

With a T440s and a Synaptics touchpad that implements Host Notify, the
payload data is always 0x0000, so I am not sure if the device actually
sends the payload or if there is a problem regarding the implementation.
Tested-by: Andrew Duggan <aduggan@synaptics.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

On a CRC error while using hardware-supported PEC, an additional
error bit is set in the auxiliary status register.  If this bit
isn't cleared, all subsequent operations will fail, essentially
hanging the controller.

The fix is simple: check, report, and clear the bit in
i801_check_post().  Also, in case the driver starts with the
hardware in that state, clear it in i801_check_pre() as well.
Signed-off-by: Ellen Wang <ellen@cumulusnetworks.com>
Tested-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

This driver does not do anything special in module init/exit. This patch
eliminates the module init/exit boilerplate code by utilizing the
module_isa_driver macro.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
[wsa: remove two empty lines while here]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

This driver does not do anything special in module init/exit. This patch
eliminates the module init/exit boilerplate code by utilizing the
module_isa_driver macro.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Simply sort header block alphabetically.

While here fix an indentation in one place and update a copyright line for
Intel.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

This patch enables I2C controllers found on Intel Edison board.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

On some platforms, such as Intel Medfield, the I2C slave devices are enumerated
through SFI tables where bus numbering is expected to be defined in the OS.
Make the bus number allocation robust for such platforms.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

I believe i2c-designware-baytrail.c doesn't have strict dependency that
Intel SoC IOSF Sideband support must be always built-in in order to be
able to compile support for Intel Baytrail I2C bus sharing HW semaphore.

Redefine build dependencies so that CONFIG_IOSF_MBI=y is required only
when CONFIG_I2C_DESIGNWARE_PLATFORM is built-in.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: David Box <david.e.box@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

This allows applications to set the transfer timeout in 10ms increments via
ioctl I2C_TIMEOUT.
Signed-off-by: Weifeng Voon <weifeng.voon@intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

qup_i2c_issue_read() derives the address from i2c_msg.
This called in the read path when I2C_M_RD flag is set.
Therefore, use the 8 bit address helper function.
Signed-off-by: Naveen Kaje <nkaje@codeaurora.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Among the bus errors reported from the QUP_MASTER_STATUS register
only NACK is considered and transfer gets suspended, while
other errors are ignored. Correct this and suspend the transfer
for other errors as well. This avoids unnecessary 'timeouts' which
happens when waiting for events that would never happen when there
is already an error condition on the bus. Also the error handling
procedure should be the same for both NACK and other bus errors in
case of dma mode. So correct that as well.
Signed-off-by: Sricharan R <sricharan@codeaurora.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

With CONFIG_DEBUG_SG is enabled and when dma mode is used, below dump is seen,

------------[ cut here ]------------
kernel BUG at include/linux/scatterlist.h:140!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.4.0-00459-g9f087b9-dirty #7
Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT)
task: ffffffc036868000 ti: ffffffc036870000 task.ti: ffffffc036870000
PC is at qup_sg_set_buf.isra.13+0x138/0x154
LR is at qup_sg_set_buf.isra.13+0x50/0x154
pc : [<ffffffc0005a0ed8>] lr : [<ffffffc0005a0df0>] pstate: 60000145
sp : ffffffc0368735c0
x29: ffffffc0368735c0 x28: ffffffc036873752
x27: ffffffc035233018 x26: ffffffc000c4e000
x25: 0000000000000000 x24: 0000000000000004
x23: 0000000000000000 x22: ffffffc035233668
x21: ffffff80004e3000 x20: ffffffc0352e0018
x19: 0000004000000000 x18: 0000000000000028
x17: 0000000000000004 x16: ffffffc0017a39c8
x15: 0000000000001cdf x14: ffffffc0019929d8
x13: ffffffc0352e0018 x12: 0000000000000000
x11: 0000000000000001 x10: 0000000000000001
x9 : ffffffc0012b2d70 x8 : ffffff80004e3000
x7 : 0000000000000018 x6 : 0000000030000000
x5 : ffffffc00199f018 x4 : ffffffc035233018
x3 : 0000000000000004 x2 : 00000000c0000000
x1 : 0000000000000003 x0 : 0000000000000000

Process swapper/0 (pid: 1, stack limit = 0xffffffc036870020)
Stack: (0xffffffc0368735c0 to 0xffffffc036874000)

sg_set_bug expects that the buf parameter passed in should be from
lowmem and a valid pageframe. This is not true for pages from
dma_alloc_coherent which can be carveouts, hence the check fails.
Change allocation of sg buffers from dma_coherent memory to kzalloc
to fix the issue. Note that now dma_map/unmap is used to make the
kzalloc'ed buffers coherent before passing it to the dmaengine.
Signed-off-by: Sricharan R <sricharan@codeaurora.org>
Reviewed-by: Andy Gross <andy.gross@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Implement fast mode plus that allows bus speeds of up to 1MHz.
Signed-off-by: David Wu <david.wu@rock-chips.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Caesar Wang <wxt@rock-chips.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

- new method to caculate i2c timings for rk3399:
  There was an timing issue about "repeated start" time at the I2C
  controller of version0, controller appears to drop SDA at .875x (7/8)
  programmed clk high. On version 1 of the controller, the rule(.875x)
  isn't enough to meet tSU;STA
  requirements on 100k's Standard-mode. To resolve this issue,
  sda_update_config, start_setup_config and stop_setup_config for I2C
  timing information are added, new rules are designed to calculate
  the timing information at new v1.
- pclk and function clk are separated at rk3399
Signed-off-by: David Wu <david.wu@rock-chips.com>
Tested-by: Caesar Wang <wxt@rock-chips.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
[wsa: fixed whitespace issue]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

The bus clock and function clock are separated at rk3399,
and others use one clock as the bus clock and function clock.
Signed-off-by: David Wu <david.wu@rock-chips.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

The i2c timing specs are really just constant data. There's no reason
to write code to init them, so move them out to structures. This not
only is a cleaner solution but it will reduce code duplication when we
introduce a new variant of rk3x_i2c_calc_divs() in a future patch.
Signed-off-by: David Wu <david.wu@rock-chips.com>
Suggested-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>