Commit Graph

2457 Commits

Author SHA1 Message Date
Greg Ungerer
17791650c3 i2c: allow configuration of imx driver for ColdFire architecture
The i2c controller used by Freescales iMX processors is the same
hardware module used on Freescales ColdFire family of processors.

We can use the existing i2c-imx driver on ColdFire family members.
Modify the configuration to allow it to be selected when compiling
for ColdFire targets.

Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-10-25 11:48:57 +02:00
David Wu
399c168ab5 i2c: rk3x: Give the tuning value 0 during rk3x_i2c_v0_calc_timings
We found a bug that i2c transfer sometimes failed on 3066a board with
stabel-4.8, the con register would be updated by uninitialized tuning
value, it made the i2c transfer failed.

So give the tuning value to be zero during rk3x_i2c_v0_calc_timings.

Signed-off-by: David Wu <david.wu@rock-chips.com>
Tested-by: Andy Yan <andy.yan@rock-chips.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2016-10-25 11:11:46 +02:00
Ruqiang Ju
ae824f0024 i2c: hix5hd2: allow build with ARCH_HISI
This driver should be buildable with ARCH_HISI,
because some of other HiSilicon SoCs also use it.

Signed-off-by: Ruqiang Ju <juruqiang@huawei.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-10-25 11:09:16 +02:00
Linus Torvalds
87840a2b7e Merge branch 'i2c/for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "Here is the 4.9 pull request from I2C including:

   - centralized error messages when registering to the core
   - improved lockdep annotations to prevent false positives
   - DT support for muxes, gates, and arbitrators
   - bus speeds can now be obtained from ACPI
   - i2c-octeon got refactored and now supports ThunderX SoCs, too
   - i2c-tegra and i2c-designware got a bigger bunch of updates
   - a couple of standard driver fixes and improvements"

* 'i2c/for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (71 commits)
  i2c: axxia: disable clks in case of failure in probe
  i2c: octeon: thunderx: Limit register access retries
  i2c: uniphier-f: fix misdetection of incomplete STOP condition
  gpio: pca953x: variable 'id' was used twice
  i2c: i801: Add support for Kaby Lake PCH-H
  gpio: pca953x: fix an incorrect lockdep warning
  i2c: add a warning to i2c_adapter_depth()
  lockdep: make MAX_LOCKDEP_SUBCLASSES unconditionally visible
  i2c: export i2c_adapter_depth()
  i2c: rk3x: Fix variable 'min_total_ns' unused warning
  i2c: rk3x: Fix sparse warning
  i2c / ACPI: Do not touch an I2C device if it belongs to another adapter
  i2c: octeon: Fix high-level controller status check
  i2c: octeon: Avoid sending STOP during recovery
  i2c: octeon: Fix set SCL recovery function
  i2c: rcar: add support for r8a7796 (R-Car M3-W)
  i2c: imx: make bus recovery through pinctrl optional
  i2c: meson: add gxbb compatible string
  i2c: uniphier-f: set the adapter to master mode when probing
  i2c: uniphier-f: avoid WARN_ON() of clk_disable() in failure path
  ...
2016-10-07 14:12:21 -07:00
Rafael J. Wysocki
0137a337d7 Merge branches 'acpi-wdat' and 'acpi-ec'
* acpi-wdat:
  watchdog: wdat_wdt: Fix warning for using 0 as NULL
  watchdog: wdat_wdt: fix return value check in wdat_wdt_probe()
  platform/x86: intel_pmc_ipc: Do not create iTCO watchdog when WDAT table exists
  i2c: i801: Do not create iTCO watchdog when WDAT table exists
  mfd: lpc_ich: Do not create iTCO watchdog when WDAT table exists
  ACPI / watchdog: Add support for WDAT hardware watchdog

* acpi-ec:
  ACPI / EC: Fix issues related to boot_ec
  ACPI / EC: Fix a gap that ECDT EC cannot handle EC events
  ACPI / EC: Fix a memory leakage issue in acpi_ec_add()
  ACPI / EC: Cleanup first_ec/boot_ec code
  ACPI / EC: Enable event freeze mode to improve event handling for suspend process
  ACPI / EC: Add PM operations to improve event handling for suspend process
  ACPI / EC: Add PM operations to improve event handling for resume process
  ACPI / EC: Fix an issue that SCI_EVT cannot be detected after event is enabled
  ACPI / EC: Add EC_FLAGS_QUERY_ENABLED to reveal a hidden logic
  ACPI / EC: Add PM operations for suspend/resume noirq stage
2016-10-02 01:40:07 +02:00
Mika Westerberg
1f6dbb022b i2c: i801: Do not create iTCO watchdog when WDAT table exists
ACPI WDAT table is the preferred way to use hardware watchdog over the
native iTCO_wdt. Windows only uses this table for its hardware watchdog
implementation so we should be relatively safe to trust it has been
validated by OEMs

Prevent iTCO watchdog creation if we detect that there is ACPI WDAT table.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-28 23:08:08 +02:00
Alexey Khoroshilov
662786a542 i2c: axxia: disable clks in case of failure in probe
axxia_i2c_probe() does not disable clock in case of failure
in i2c_add_adapter(). Also it ignores returned value from
clk_prepare_enable().

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-24 11:26:55 +02:00
Jan Glauber
70121f7f37 i2c: octeon: thunderx: Limit register access retries
Do not infinitely retry register readq and writeq operations
in order to not lock up the CPU in case the TWSI gets stuck.

Return -ETIMEDOUT in case of a failed data read. For all other
cases just return so subsequent operations will fail.

Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-24 11:22:24 +02:00
Masahiro Yamada
fcbd4bddb3 i2c: uniphier-f: fix misdetection of incomplete STOP condition
Currently, the status register FI2C_SR is checked immediately after
a STOP condition is issued in case of the deferred STOP condition.
It takes typically 5-10 usec until the corresponding bits in the
register are set, so the error check for "stop condition was not
completed" is very likely to be false positive.

Add wait code to relax the status register check.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-24 11:19:15 +02:00
Andy Shevchenko
31158763ef i2c: i801: Add support for Kaby Lake PCH-H
Intel Kaby Lake PCH-H has the same legacy SMBus host controller than Intel
Sunrisepoint PCH. It also has same iTCO watchdog on the bus.

Add Kaby Lake PCH-H PCI ID to the list of supported devices.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-24 10:57:56 +02:00
Sudeep Holla
331dcf421c i2c: qup: skip qup_i2c_suspend if the device is already runtime suspended
If the i2c device is already runtime suspended, if qup_i2c_suspend is
executed during suspend-to-idle or suspend-to-ram it will result in the
following splat:

WARNING: CPU: 3 PID: 1593 at drivers/clk/clk.c:476 clk_core_unprepare+0x80/0x90
Modules linked in:

CPU: 3 PID: 1593 Comm: bash Tainted: G        W       4.8.0-rc3 #14
Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT)
PC is at clk_core_unprepare+0x80/0x90
LR is at clk_unprepare+0x28/0x40
pc : [<ffff0000086eecf0>] lr : [<ffff0000086f0c58>] pstate: 60000145
Call trace:
 clk_core_unprepare+0x80/0x90
 qup_i2c_disable_clocks+0x2c/0x68
 qup_i2c_suspend+0x10/0x20
 platform_pm_suspend+0x24/0x68
 ...

This patch fixes the issue by executing qup_i2c_pm_suspend_runtime
conditionally in qup_i2c_suspend.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Reviewed-by: Andy Gross <andy.gross@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2016-09-22 20:11:14 +02:00
David Wu
72cf8c565c i2c: rk3x: Fix variable 'min_total_ns' unused warning
This patch fixs the following warning:
drivers/i2c/busses/i2c-rk3x.c: In function 'rk3x_i2c_v1_calc_timings':
drivers/i2c/busses/i2c-rk3x.c:745:41: warning: variable 'min_total_ns' set but not used [-Wunused-but-set-variable]

Reported-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: David Wu <david.wu@rock-chips.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-22 19:51:38 +02:00
David Wu
a8a7d09e73 i2c: rk3x: Fix sparse warning
This patch fixes the following sparse warning:
drivers/i2c/busses/i2c-rk3x.c:888:17: warning: cast truncates bits from constant value (ffffffffff00 becomes ffffff00)

Reported-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: David Wu <david.wu@rock-chips.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-22 19:50:15 +02:00
Jan Glauber
38caa925ee i2c: octeon: Fix high-level controller status check
In case the high-level controller (HLC) is used the status code is
reported at a different location. Check that location after HLC
write operations if the ready bit is not set and return an appropriate
error code instead of always returning -EAGAIN.

Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-21 23:04:42 +02:00
Dmitry Bazhenov
de919ff6a0 i2c: octeon: Avoid sending STOP during recovery
Due to a bug in the ThunderX I2C hardware sending STOP during
a recovery attempt could lock up the hardware. To work around
this problem do not send STOP at the beginning of the recovery
but use the override registers to bring the TWSI including
the high-level controller out of the bad state.

Signed-off-by: Dmitry Bazhenov <dmitry.bazhenov@auriga.com>
Signed-off-by: Jan Glauber <jglauber@cavium.com>
[Changed commit message]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-21 23:04:35 +02:00
Dmitry Bazhenov
e7051556b6 i2c: octeon: Fix set SCL recovery function
The set SCL recovery function unconditionally pulls the SCL line low.
Only pull SCL line low according to val parameter.

Signed-off-by: Dmitry Bazhenov <dmitry.bazhenov@auriga.com>
Signed-off-by: Jan Glauber <jglauber@cavium.com>
[Changed commit message]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-21 22:58:25 +02:00
Yadi.hu
371a015344 i2c-eg20t: fix race between i2c init and interrupt enable
the eg20t driver call request_irq() function before the pch_base_address,
base address of i2c controller's register, is assigned an effective value.

there is one possible scenario that an interrupt which isn't inside eg20t
arrives immediately after request_irq() is executed when i2c controller
shares an interrupt number with others. since the interrupt handler
pch_i2c_handler() has already active as shared action, it will be called
and read its own register to determine if this interrupt is from itself.

At that moment, since base address of i2c registers is not remapped
in kernel space yet,so the INT handler will access an illegal address
and then a error occurs.

Signed-off-by: Yadi.hu <yadi.hu@windriver.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2016-09-21 18:07:51 +02:00
Ulrich Hecht
c13f743aee i2c: rcar: add support for r8a7796 (R-Car M3-W)
Same as r8a7795.

Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-16 19:46:10 +02:00
Yang Li
fd8961c5ba i2c: imx: make bus recovery through pinctrl optional
Since commit 1c4b6c3bcf ("i2c: imx: implement bus recovery") the
driver starts to use gpio/pinctrl to support optional bus recovery
feature.  But pinctrl is not always usable.  There are platforms such
as ls1021a and ls1043a that don't support pinctrl, and it could just
be broken due to old/broken device tree.  The patch makes it really
optional that the probe function won't bailout on pinctrl problems
instead it just disables bus recovery and prints out notification when
there is problem with pinctrl.  Since pinctrl is only used by bus
recovery in this driver, move pinctrl initialization into bus recovery
init function to prevent confusion.

Signed-off-by: Li Yang <leoyang.li@nxp.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-15 21:44:18 +02:00
Neil Armstrong
d1050caea4 i2c: meson: add gxbb compatible string
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Acked-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-15 21:37:16 +02:00
Doug Anderson
cbfff439c5 i2c: rk3x: Restore clock settings at resume time
Depending on a number of factors including:
- Which exact Rockchip SoC we're working with
- How deep we suspend
- Which i2c port we're on

We might lose the state of the i2c registers at suspend time.
Specifically we've found that on rk3399 the i2c ports that are not in
the PMU power domain lose their state with the current suspend depth
configured by ARM Tursted Firmware.

Note that there are very few actual i2c registers that aren't configured
per transfer anyway so all we actually need to re-configure are the
clock config registers.  We'll just add a call to rk3x_i2c_adapt_div()
at resume time and be done with it.

NOTE: On rk3399 on ports whose power was lost, I put printouts in at
resume time.  I saw things like:
  before: con=0x00010300, div=0x00060006
  after:  con=0x00010200, div=0x00180025

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: David Wu <david.wu@rock-chips.com>
Tested-by: David Wu <david.wu@rock-chips.com>
[wsa: removed duplicate const]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-08 22:50:33 +02:00
Masahiro Yamada
0b1c7716fd i2c: uniphier-f: set the adapter to master mode when probing
Currently, the adapter is set to the master mode at the first use.
Since then, it is kept in the slave mode, so unexpected glitch
signals on the I2C lines may cause the adapter into insane state.
Setting it to the master mode along with initialization solves the
problem.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reported-by: Akio Noda <noda.akio@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-08 22:41:31 +02:00
Masahiro Yamada
405188e86a i2c: uniphier-f: avoid WARN_ON() of clk_disable() in failure path
If clk_prepare_enable() fails, clk_disable_unprepare() is called in
the failure path, where the enable_count is still zero, so it hits
WARN_ON(core->enable_count == 0) in the clk_core_disable().

To fix this, make the clock setting more linear in the probe function
so that it can exploit "goto err" in case of error.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-08 22:41:02 +02:00
Masahiro Yamada
4c91307ce9 i2c: uniphier: avoid WARN_ON() of clk_disable() in failure path
If clk_prepare_enable() fails, clk_disable_unprepare() is called in
the failure path, where the enable_count is still zero, so it hits
WARN_ON(core->enable_count == 0) in the clk_core_disable().

To fix this, make the clock setting more linear in the probe function
so that it can exploit "goto err" in case of error.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-08 22:40:32 +02:00
Jon Hunter
fbf8090b72 i2c: tegra: Fix assignment of boolean variables
Fix the following warnings reported by coccinelle for the Tegra I2C
driver.

drivers/i2c/busses/i2c-tegra.c:513:2-23: WARNING: Assignment of bool to 0/1
drivers/i2c/busses/i2c-tegra.c:539:3-24: WARNING: Assignment of bool to 0/1

Reported-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-08 22:36:18 +02:00
Shardar Shariff Md
77821b4678 i2c: tegra: proper handling of error cases
To summarize the issue observed in error cases:

SW Flow: For i2c message transfer, packet header and data payload is
posted and then required error/packet completion interrupts are enabled
later.

HW flow: HW process the packet just after packet header is posted, if
ARB lost/NACK error occurs (SW will not handle immediately when error
happens as error interrupts are not enabled at this point). HW assumes
error is acknowledged and clears current data in FIFO, But SW here posts
the remaining data payload which still stays in FIFO as stale data
(data without packet header).

Now once the interrupts are enabled, SW handles ARB lost/NACK error by
clearing the ARB lost/NACK interrupt. Now HW assumes that SW attended
the error and will parse/process stale data (data without packet header)
present in FIFO which causes invalid NACK errors.

Fix: Enable the error interrupts before posting the packet into FIFO
which make sure HW to not clear the fifo. Also disable the packet mode
before acknowledging errors (ARB lost/NACK error) to not process any
stale data. As error interrupts are enabled before posting the packet
header use spinlock to avoid preempting.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-08 22:34:58 +02:00
Shardar Shariff Md
2bc445e225 i2c: tegra: use atomic poll function during configuration
Use readl_poll_timeout_atomic() function as *wait_for_config_load()
function can be called from interrupt context.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-08 22:34:23 +02:00
Shardar Shariff Md
89120d66fc i2c: tegra: add separate function for config_load programing
Define separate function for configuration load register handling
to make it use by different functions later.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-08 22:33:51 +02:00
Shardar Shariff Md
2148c01cce i2c: tegra: If fifo flush fails return error
During i2c controller initialization, when fifo flush fails return error
instead of returning the error during exit.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-08 22:33:19 +02:00
Shardar Shariff Md
685143a159 i2c: tegra: use readl_poll_timeout after config_load reg programmed
After CONFIG_LOAD register is programmed instead of explicitly waiting
for timeout, use readl_poll_timeout() to check for register value to get
updated or wait till timeout.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-08 22:32:46 +02:00
Geert Uytterhoeven
17f80487f6 i2c: shmobile: Use ARCH_SHMOBILE instead of SUPERH
"i2c-sh_mobile" is used on sh7343, sh7366, sh7722, sh7723, and sh7724
only. As all of the above select ARCH_SHMOBILE, restrict its driver
dependencies from SUPERH to ARCH_SHMOBILE.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-08 22:24:13 +02:00
Geert Uytterhoeven
e0603c8dd2 i2c: Spelling s/acknowedge/acknowledge/
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-08 22:22:20 +02:00
Zhuo-hao Lee
664d58bf4d i2c: designware: save the preset value of DW_IC_SDA_HOLD
There are several ways to set the SDA hold time for i2c controller,
including: Device Tree, built-in device properties and ACPI. However,
if the SDA hold time is not specified by above method, we should
read the value, where it is preset by firmware, and save it to
sda_hold_time. This is needed because when i2c controller enters
runtime suspend, the DW_IC_SDA_HOLD value will be reset to chipset
default value. And during runtime resume, i2c_dw_init will be called
to reconfigure i2c controller. If sda_hold_time is zero, the chipset
default hold time will be used, that will be too short for some
platforms. Therefore, to have a better tolerance, the DW_IC_SDA_HOLD
value should be kept by sda_hold_time.

Signed-off-by: Zhuo-hao Lee <zhuo-hao.lee@intel.com>
Reviewed-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>
2016-09-08 22:14:36 +02:00
Jon Hunter
718917b987 i2c: tegra: Add pinctrl support
On Tegra124/132 the pins for I2C6 are shared with the Display Port AUX
(DPAUX) channel and on Tegra210 the pins for I2C4 and I2C6 are shared
with DPAUX1 and DPAUX0, respectively. The multiplexing of the pins is
handled by a register in the DPAUX and so the Tegra DPAUX driver has
been updated to register a pinctrl device for managing these pins.

The pins for these particular I2C devices are bound to the I2C device
prior to probing. However, these I2C devices are in a different power
partition to the DPAUX devices that own the pins. Hence, it is desirable
to place the pins in the 'idle' state and allow the DPAUX power
partition to switch off, when these I2C devices is not in use.
Therefore, add calls to place the I2C pins in the 'default' and 'idle'
states when the I2C device is runtime resumed and suspended,
respectively.

Please note that the pinctrl functions that set the state of the pins
check to see if the devices has pins associated and will return zero
if they do not. Therefore, it is safe to call these pinctrl functions
even for I2C devices that do not have any pins associated.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-30 22:01:12 +02:00
Jon Hunter
1f50ad2c86 i2c: tegra: Add runtime power-management support
Update the Tegra I2C driver to use runtime PM and move the code in the
tegra_i2c_clock_enable/disable() functions to the PM runtime resume and
suspend callbacks, respectively.

Note that given that CONFIG_PM is not mandatory for Tegra, if CONFIG_PM
is not enabled and so runtime PM is not enabled, ensure that the I2C
clocks are turned on during probe and kept on by calling the resume
callback directly.

In the function tegra_i2c_init(), the variable 'err' does not need to be
initialised to zero in tegra_i2c_init() because it is initialised when
pm_runtime_get_sync() is called. Furthermore, to ensure we only return 0
from tegra_i2c_init(), it is necessary to re-initialise 'err' to 0 after
a successful call to pm_runtime_get_sync() because it can return a
positive value on success. However, alternatively re-initialise 'err' by
using the return value of the function tegra_i2c_flush_fifos() because
it can only be 0 or -ETIMEDOUT.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-30 22:00:40 +02:00
Jon Hunter
f4c2d89bd4 i2c: tegra: Simplify I2C resume
The I2C adapter is unlocked regardless of whether the tegra_i2c_init()
called during the resume is successful or not. However, if the
tegra_i2c_init() is not successful, then ->is_suspended is not set to
false. Simplify the resume code by only setting ->is_suspended to false
if tegra_i2c_init() is successful and return the error code from
tegra_i2c_init().

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-30 22:00:08 +02:00
Jon Hunter
0da9ab89ab i2c: tegra: Use device name for adapter name
All Tegra I2C devices have the name "Tegra I2C adapter" which is not
very useful when viewing the I2C adapter names via the sysfs. Therefore,
use the device name, which is unique for each I2C device, instead.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-30 21:59:37 +02:00
Jon Hunter
a9e32cd816 i2c: tegra: Remove non device-tree support
Tegra has only supported device-tree for platform/board configuration
for quite some time now and so simplify the Tegra I2C driver by dropping
code for non device-tree platforms/boards.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-30 21:59:06 +02:00
Jon Hunter
e8e999cbe7 i2c: tegra: Add missing new line characters
Add missing new line characters for the various error messages.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-30 21:58:35 +02:00
Jon Hunter
f5076685b3 i2c: tegra: Fix missing blank lines after declarations
Checkpatch warns about missing blank lines after declarations in the
Tegra I2C driver and so fix these.

Note that the initialisation of 'val' to zero in tegra_dvc_init() is
unnecessary and so remove this.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-30 21:58:03 +02:00
Jon Hunter
2929be29e0 i2c: tegra: Use BIT macro
Checkpatch warns about spacing around the '<<' operator in the Tegra I2C
driver and so fix these by converting the bit definitions that are using
this operator to use the BIT macro.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-30 21:57:32 +02:00
Jon Hunter
c7ae44e8aa i2c: tegra: Fix lines over 80 characters
Checkpatch warns about some lines over 80 characters in the Tegra I2C
driver and so fix these.

While we are at it, prefix the second instance of "STOP condition" in
the comment with a "the".

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-30 21:57:00 +02:00
Lucas De Marchi
0317e6c0f1 i2c: designware: do not disable adapter after transfer
Disabling the adapter after each transfer adds additional delays
for each I2C transfer. Even if we don't wait for it to be disabled
anymore, on next transfer we will need to if we have several transfers
in a row.

Now during the transfer init we check if IC_TAR can be changed
dynamically, the status register for no activity and TX buffer being
empty. In this case we don't need to disable it

When a transfer fails the adapter will still be disabled - this is a
conservative approach. When transfers succeed, the adapter is left
enabled and it's configured so to disable interrupts.

Alternating register reads on 2 slaves:
perf stat -r4 chrt -f 10 ./i2c-test /dev/i2c-1 25000 0x40 0x6 0x1e 0x00

Before:
	8.638705161 seconds time elapsed                  ( +-  5.90% )
After:
	7.516821591 seconds time elapsed                  ( +-  0.11% )

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Christian Ruppert <christian.ruppert@alitech.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-26 00:42:16 +02:00
Lucas De Marchi
63d0f0a695 i2c: designware: detect when dynamic tar update is possible
This adapter can be synthesized with dynamic tar update enabled or disabled.
When enabled it is not necessary to disable the adapter to change the slave
address in some situations, which saves some time per transaction.

There is no direct register to know if this feature is enabled but we can do it
indirectly by writing to the 10BIT_ADDR field in IC_CON: this field is
read only when dynamic tar update is enabled.

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Christian Ruppert <christian.ruppert@alitech.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-26 00:42:15 +02:00
Lucas De Marchi
8c5660bb29 i2c: designware: add common functions for locking
These are used in 2 places and will be needed in more.

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Christian Ruppert <christian.ruppert@alitech.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-26 00:42:14 +02:00
José Roberto de Souza
2702ea7dbe i2c: designware: wait for disable/enable only if necessary
If we aren't going to continue using the controller we can just disable
it instead of waiting for it to complete. The biggest improvement here
is when a I2C transaction is completed and it doesn't block until
the adapter is disabled. When a new transfer is needed we will disable
and wait for its completion.

This way the adapter will continue changing its state in parallel to the
execution of the thread that requested the I2C transaction saving most
of the time 25~250 usec per I2C transaction.

A simple program doing a register read (1 byte write, 1 byte read)
alternating on 2 different slaves repeated 25k times for each and
measurements taken 4 times we get:

perf stat -r4 chrt -f 10 ./i2c-test /dev/i2c-1 25000 0x40 0x6 0x1e 0x00

Before:
	30.879317977 seconds time elapsed                 ( +- 14.83% )
After:
	8.638705161 seconds time elapsed                  ( +-  5.90% )

Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Christian Ruppert <christian.ruppert@alitech.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-26 00:42:12 +02:00
Jarkko Nikula
10f8e7fb37 i2c: designware: Find bus speed from ACPI
Fast mode is the default speed of i2c-designware which can be overridden
by platform data or by "clock-frequency" device property. Even though
the ACPI 5.1 can pass device properties via _DSD method, shipping systems
define the connection speed between I2C host and each slave in their
I2cSerialBus resources. Which means speed is not defined per bus but per
slave.

As there is now support in i2c-core to find the bus speed from ACPI use
that to set up the bus speed prior registering the I2C adapter.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-26 00:42:11 +02:00
Weifeng Voon
b6e67145f1 i2c: designware: Enable high speed mode
This patch enabled high speed mode. High speed mode can be turn on by
setting the clk_freq to 3400000. High speed HCNT and LCNT are needed
as there is no default value provided.

Signed-off-by: Weifeng Voon <weifeng.voon@intel.com>
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-26 00:42:07 +02:00
Weifeng Voon
548e6695d1 i2c: designware: set the common config before the if else
DW_IC_CON_MASTER, DW_IC_CON_SLAVE_DISABLE and DW_IC_CON_RESTART_EN are
common config that need to be set for i2c designware master. So, configure
it first without having to repeat inside the if else.

Signed-off-by: Weifeng Voon <weifeng.voon@intel.com>
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-26 00:42:06 +02:00
Weifeng Voon
d608c3d9ac i2c: designware: Enable fast mode plus
This patch enabled fast mode plus. The fast mode plus and fast speed
share the same HCNT and LCNT register. So, the fast mode plus will only
run when the HCNT and LCNT value is provided. Else, it will run at fast
speed as default.

Signed-off-by: Weifeng Voon <weifeng.voon@intel.com>
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-26 00:42:05 +02:00