Commit Graph

43 Commits

Author SHA1 Message Date
Dejin Zheng e42688ed5c i2c: busses: remove duplicate dev_err()
it will print an error message by itself when platform_get_irq()
goes wrong. so don't need dev_err() in here again.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Suggested-by: Markus Elfring <Markus.Elfring@web.de>
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-04-18 23:42:14 +02:00
Dejin Zheng e0442d7621 i2c: busses: convert to devm_platform_ioremap_resource
use devm_platform_ioremap_resource() to simplify code, it
contains platform_get_resource and devm_ioremap_resource.

Reviewed-by: Barry Song <baohua@kernel.org>
Acked-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Robert Richter <rrichter@marvell.com>
Acked-by: Thor Thayer <thor.thayer@linux.intel.com>
Acked-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-04-15 12:09:09 +02:00
Andy Shevchenko 90224e6468 i2c: drivers: Use generic definitions for bus frequencies
Since we have generic definitions for bus frequencies, let's use them.

Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Acked-by: Robert Richter <rrichter@marvell.com>
Reviewed-by: Thor Thayer <thor.thayer@linux.intel.com>
Acked-by: Elie Morisse <syniurge@gmail.com>
Acked-by: Nehal Shah <nehal-bakulchandra.shah@amd.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Vladimir Zapolskiy <vz@mleia.com>
Acked-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Chris Brandt <chris.brandt@renesas.com>
Reviewed-by: Baolin Wang <baolin.wang7@gmail.com>
Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>
Acked-by: Patrice Chotard <patrice.chotard@st.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-03-24 22:36:59 +01:00
Thomas Gleixner d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00
Shawn Lin 17dd94796c i2c: rk3x: Don't print visible virtual mapping MMIO address
Now %p doesn't print visible pointer address unless the user
really want it. According to Documentation/core-api/printk-formats.rst,
%px should be used instead, otherwise we could see:

rk3x-i2c ff110000.i2c: Initialized RK3xxx I2C bus at (____ptrval____)
rk3x-i2c ff130000.i2c: Initialized RK3xxx I2C bus at (____ptrval____)
rk3x-i2c ff3c0000.i2c: Initialized RK3xxx I2C bus at (____ptrval____)
rk3x-i2c ff3d0000.i2c: Initialized RK3xxx I2C bus at (____ptrval____)

But I don't really understand why we need dump it in the first place!
Let's remove the whole pointless log.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-05-24 22:09:05 +02:00
Wolfram Sang 5bacb56b2b i2c: rk3x: add proper kerneldoc header
gcc noticed the kerneldoc was wrongly formatted. Fix it!

drivers/i2c/busses/i2c-rk3x.c:164: warning:
  Cannot understand  * @grf_offset: ...
  on line 164 - I thought it was a doc line

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
2018-01-18 00:34:09 +01:00
Julia Lawall d032a2eb2e i2c: rk3x: account for const type of of_device_id.data
This driver creates a number of const structures that it stores in
the data field of an of_device_id array.

The data field of an of_device_id structure has type const void *, so
there is no need for a const-discarding cast when putting const values
into such a structure.

Furthermore, adding const to the declaration of the location that
receives a const value from such a field ensures that the compiler
will continue to check that the value is not modified.  The
const-discarding cast on the extraction from the data field is thus
no longer needed.

Done using Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-18 00:10:30 +01:00
Andy Yan 0dbb9634e5 i2c: rk3x: add support for rv1108
Support for the i2c controller on rv1108 soc.

Signed-off-by: Andy Yan <andy.yan@rock-chips.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-08-12 16:39:47 +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
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
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
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
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
Wolfram Sang ea734404f3 i2c: don't print error when adding adapter fails
The core will do this for us now.

Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Peter Korsgaard <peter@korsgaard.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Ray Jui <ray.jui@broadcom.com>
Acked-by: Vladimir Zapolskiy <vz@mleia.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-22 08:19:55 +02:00
David Wu a02f3d081a i2c: rk3x: support fast-mode plus for rk3399
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>
2016-06-17 13:55:28 +02:00
David Wu 7e086c3fc2 i2c: rk3x: add i2c support for rk3399 soc
- 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>
2016-06-17 13:55:03 +02:00
David Wu b58fd3be40 i2c: rk3x: Move spec timing data to "static const" structs
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>
2016-06-17 13:39:15 +02:00
David Wu bef358c4fe i2c: rk3x: Change SoC data to not use array
Specifying the i2c SoC data in an array provides very little benefit and
gets unwieldly / confusing as the array grows since the next bit of code
needs to refer to elements in the array by their raw integral index.

Let's just create a single 'static const' structure for each SoC so that
we can refer to these structures by ID.

Signed-off-by: David Wu <david.wu@rock-chips.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
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>
2016-06-17 13:39:15 +02:00
David Wu 69eda367ac i2c: rk3x: Remove redundant rk3x_i2c_clean_ipd()
rk3x_i2c_setup() gets called directly before rk3x_i2c_start(),
and the last thing in setup was to clean the IPD, so no reason
to do it at the beginning of start.

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>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-06-17 13:39:15 +02:00
David Wu e26747bf53 i2c: rk3x: use struct "rk3x_i2c_calced_timings"
The "div_high" and "div_low" values are always used together.
Group them into a structure to make it easier to pass them
both around. This structure also provides a place for future
calculated timings.

Signed-off-by: David Wu <david.wu@rock-chips.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-06-17 13:39:15 +02:00
David Wu 0a6ad2f95f i2c: rk3x: add documentation to fields in "struct rk3x_i2c"
Add kernel-doc documentation for the elements of the previously
undocumented struct rk3x_i2c.

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>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-06-17 13:39:15 +02:00
Linus Torvalds 78975f23cb Merge branch 'i2c/for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:

 - Peter Rosin did some major rework on the locking of i2c muxes by
   seperating parent-locked muxes and mux-locked muxes.

   This avoids deadlocks/workarounds when the mux itself needs i2c
   commands for muxing.  And as a side-effect, other workarounds in the
   media layer could be eliminated.  Also, Peter stepped up as the i2c
   mux maintainer and will keep an eye on these changes.

 - major updates to the octeon driver

 - add a helper to the core to generate the address+rw_bit octal and
   make drivers use it

 - quite a bunch of driver updates

* 'i2c/for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (84 commits)
  i2c: rcar: add DMA support
  i2c: st: Implement bus clear
  i2c: only check scl functions when using generic recovery
  i2c: algo-bit: declare i2c_bit_quirk_no_clk_stretch as static
  i2c: tegra: disable clock before returning error
  [media] rtl2832: regmap is aware of lockdep, drop local locking hack
  [media] rtl2832_sdr: get rid of empty regmap wrappers
  [media] rtl2832: change the i2c gate to be mux-locked
  [media] si2168: change the i2c gate to be mux-locked
  iio: imu: inv_mpu6050: change the i2c gate to be mux-locked
  i2c: mux: document i2c muxes and elaborate on parent-/mux-locked muxes
  i2c: mux: relax locking of the top i2c adapter during mux-locked muxing
  i2c: muxes always lock the parent adapter
  i2c: allow adapter drivers to override the adapter locking
  i2c: uniphier: add "\n" at the end of error log
  i2c: mv64xxx: remove CONFIG_HAVE_CLK conditionals
  i2c: mv64xxx: use clk_{prepare_enable,disable_unprepare}
  i2c: mv64xxx: handle probe deferral for the clock
  i2c: mv64xxx: enable the driver on ARCH_MVEBU
  i2c: octeon: Add workaround for broken irqs on CN3860
  ...
2016-05-19 17:48:12 -07:00
David Wu 1ab92956d4 i2c: rk3x: switch to i2c generic dt parsing
Switch to the new generic functions: i2c_parse_fw_timings().

Signed-off-by: David Wu <david.wu@rock-chips.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-04-14 20:37:46 +02:00
Yakir Yang b0b6d123f5 i2c: rk3x: add support for rk3228
Enable the I2C core for this SoC.

Signed-off-by: Yakir Yang <ykk@rock-chips.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-04-12 23:34:44 +02:00
Wolfram Sang 9abd29e7c1 i2c: rk3x: populate correct variable for sda_falling_time
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Cc: stable@kernel.org
2015-11-30 14:27:41 +01:00
Luis de Bethencourt 598cf1611b i2c: rk3x: Fix module autoload for OF platform driver
This platform driver has a OF device ID table but the OF module
alias information is not created so module autoloading won't work.

Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-20 18:15:03 +02:00
Doug Anderson 4489750fa5 i2c: rk3x: Increase wait timeout to 1 second
Although unlikely, it is remotely possible for an i2c command to need
more than 200ms complete. Unlike smbus, i2c devices can clock stretch
for an unspecified amount of time. The longest time I've seen
specified for a device is 144ms (bq27541 battery gas), but one could
imagine a device taking a bit slower. 1 second "ought to be enough for
anyone."

The above is not the only justifcation for going above 200ms for a
timeout, though.  It turns out that if you've got a large number of
printks going out to a serial console, interrupts on a CPU can be
disabled for hundreds of milliseconds. That's not a great situation to
be in to start with (maybe we should put a cap in vprintk_emit()) but
it's pretty annoying to start seeing unexplained i2c timeouts.

Note that to understand why we can timeout when printk has interrupts
disabled, you need to understand that on current Linux ARM kernels
interrupts are routed to a single CPU in a multicore system. Thus,
you can get:

1. CPU1 is running rk3x_i2c_xfer()
2. CPU0 calls vprintk_emit(), which disables all IRQs on CPU0.
3. I2C interrupt is ready but is set to only run on CPU0, where IRQs
   are disabled.
4. CPU1 timeout expires. I2C interrupt is still ready, but CPU0 is
   still sitting in the same vprintk_emit()
5. CPU1 sees that no interrupt happened in 200ms, so timeout.

A normal system shouldn't see i2c timeouts anyway, so increasing the
timeout should help people debugging without hurting other people
excessively.

Signed-off-by: Doug Anderson <dianders@chromium.org>
Tested-by: Caesar Wang <wxt@rock-chips.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-05-12 15:15:17 +02:00
Dmitry Torokhov c6cbfb91b8 i2c: rk3x: report number of messages transmitted
master_xfer() method should return number of i2c messages transferred,
but on Rockchip we were usually returning just 1, which caused trouble
with users that actually check number of transferred messages vs.
checking for negative error codes.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2015-04-23 19:35:28 +02:00
Doug Anderson 387f0de6c3 i2c: rk3x: Account for repeated start time requirement
On Rockchip I2C the controller drops SDA low slightly too soon to meet
the "repeated start" requirements.

>From my own experimentation over a number of rates:
 - controller appears to drop SDA at .875x (7/8) programmed clk high.
 - controller appears to keep SCL high for 2x programmed clk high.

The first rule isn't enough to meet tSU;STA requirements in
Standard-mode on the system I tested on.  The second rule is probably
enough to meet tHD;STA requirements in nearly all cases (especially
after accounting for the first), but it doesn't hurt to account for it
anyway just in case.

Even though the repeated start requirement only need to be accounted
for during a small part of the transfer, we'll adjust the timings for
the whole transfer to meet it.  I believe that adjusting the timings
in just the right place to switch things up for repeated start would
require several extra interrupts and that doesn't seem terribly worth
it.

With this change and worst case rise/fall times, I see 100kHz i2c
going to ~85kHz.  With slightly optimized rise/fall (800ns / 50ns) I
see i2c going to ~89kHz.  Fast-mode isn't affected much because
tSU;STA is shorter relative to tHD;STA there.

As part of this change we needed to account for the SDA falling time.
The specification indicates that this should be the same, but we'll
follow Designware's lead and add a binding.  Note that we deviate from
Designware and assign the default SDA falling time to be the same as
the SCL falling time, which is incredibly likely.

Signed-off-by: Doug Anderson <dianders@chromium.org>
[wsa: rebased to i2c/for-next]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-13 16:21:05 +01:00
addy ke 1330e29105 i2c: rk3x: fix bug that cause measured high_ns doesn't meet I2C specification
The number of clock cycles to be written into the CLKDIV register
that determines the I2C clk high phase includes the rise time.
So to meet the timing requirements defined in the I2C specification
which defines the minimal time SCL has to be high, the rise time
has to taken into account. The same applies to the low phase with
falling time.

In my test on RK3288-Pink2 board, which is not an upstream board yet,
if external pull-up resistor is 4.7K, rise_ns is about 700ns.
So the measured high_ns is about 3900ns, which is less than 4000ns
(the minimum high_ns in I2C specification for Standard-mode).

To fix this bug min_low_ns should include fall time and min_high_ns
should include rise time.

This patch merged the patch from chromium project which can get the
rise and fall times for signals from the device tree. This allows us
to more accurately calculate timings. see:
https://chromium-review.googlesource.com/#/c/232774/

Signed-off-by: Addy Ke <addy.ke@rock-chips.com>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Tested-by: Doug Anderson <dianders@chromium.org>
[wsa: fixed a typo in the docs]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-13 16:21:04 +01:00
Linus Torvalds e6b5be2be4 Driver core patches for 3.19-rc1
Here's the set of driver core patches for 3.19-rc1.
 
 They are dominated by the removal of the .owner field in platform
 drivers.  They touch a lot of files, but they are "simple" changes, just
 removing a line in a structure.
 
 Other than that, a few minor driver core and debugfs changes.  There are
 some ath9k patches coming in through this tree that have been acked by
 the wireless maintainers as they relied on the debugfs changes.
 
 Everything has been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core update from Greg KH:
 "Here's the set of driver core patches for 3.19-rc1.

  They are dominated by the removal of the .owner field in platform
  drivers.  They touch a lot of files, but they are "simple" changes,
  just removing a line in a structure.

  Other than that, a few minor driver core and debugfs changes.  There
  are some ath9k patches coming in through this tree that have been
  acked by the wireless maintainers as they relied on the debugfs
  changes.

  Everything has been in linux-next for a while"

* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
  Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
  fs: debugfs: add forward declaration for struct device type
  firmware class: Deletion of an unnecessary check before the function call "vunmap"
  firmware loader: fix hung task warning dump
  devcoredump: provide a one-way disable function
  device: Add dev_<level>_once variants
  ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
  ath: use seq_file api for ath9k debugfs files
  debugfs: add helper function to create device related seq_file
  drivers/base: cacheinfo: remove noisy error boot message
  Revert "core: platform: add warning if driver has no owner"
  drivers: base: support cpu cache information interface to userspace via sysfs
  drivers: base: add cpu_device_create to support per-cpu devices
  topology: replace custom attribute macros with standard DEVICE_ATTR*
  cpumask: factor out show_cpumap into separate helper function
  driver core: Fix unbalanced device reference in drivers_probe
  driver core: fix race with userland in device_add()
  sysfs/kernfs: make read requests on pre-alloc files use the buffer.
  sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
  fs: sysfs: return EGBIG on write if offset is larger than file size
  ...
2014-12-14 16:10:09 -08:00
Max Schwarz 249051f499 i2c: rk3x: handle dynamic clock rate changes correctly
The i2c input clock can change dynamically, e.g. on the RK3066 where
pclk_i2c0 and pclk_i2c1 are connected to the armclk, which changes
rate on cpu frequency scaling.

Until now, we incorrectly called clk_get_rate() while holding the
i2c->lock in rk3x_i2c_xfer() to adapt to clock rate changes.
Thanks to Huang Tao for reporting this issue.

Do it properly now using the clk notifier framework. The callback
logic was taken from i2c-cadence.c.

Also rename all misleading "i2c_rate" variables to "clk_rate", as they
describe the *input* clk rate.

Signed-off-by: Max Schwarz <max.schwarz@online.de>
Tested-by: Doug Anderson <dianders@chromium.org> on RK3288
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-23 17:27:46 +01:00
addy ke 0285f8f5fd i2c: rk3x: adjust the LOW divison based on characteristics of SCL
As show in I2C specification:
- Standard-mode: the minimum HIGH period of the scl clock is 4.0us
                 the minimum LOW period of the scl clock is 4.7us
- Fast-mode: the minimum HIGH period of the scl clock is 0.6us
             the minimum LOW period of the scl clock is 1.3us

I have measured i2c SCL waveforms in fast-mode by oscilloscope
on rk3288-pinky board. the LOW period of the scl clock is 1.3us.
It is so critical that we must adjust LOW division to increase
the LOW period of the scl clock.

Thanks Doug for the suggestion about division formulas.

Signed-off-by: Addy Ke <addy.ke@rock-chips.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Max Schwarz <max.schwarz@online.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-10 15:56:26 +01:00
Wolfram Sang 1ecc4335eb i2c: busses: drop owner assignment from platform_drivers
A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-10-20 16:20:37 +02:00
Linus Torvalds 278f1d0730 Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "Highlights from the I2C subsystem for 3.18:

   - new drivers for Axxia AM55xx, and Hisilicon hix5hd2 SoC.

   - designware driver gained AMD support, exynos gained exynos7 support

  The rest is usual driver stuff.  Hopefully no lowlights this time"

* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: i801: Add Device IDs for Intel Sunrise Point PCH
  i2c: hix5hd2: add i2c controller driver
  i2c-imx: Disable the clock on probe failure
  i2c: designware: Add support for AMD I2C controller
  i2c: designware: Rework probe() to get clock a bit later
  i2c: designware: Default to fast mode in case of ACPI
  i2c: axxia: Add I2C driver for AXM55xx
  i2c: exynos: add support for HSI2C module on Exynos7
  i2c: mxs: detect No Slave Ack on SELECT in PIO mode
  i2c: cros_ec: Remove EC_I2C_FLAG_10BIT
  i2c: cros-ec-tunnel: Add of match table
  i2c: rcar: remove sign-compare flaw
  i2c: ismt: Use minimum descriptor size
  i2c: imx: Add arbitration lost check
  i2c: rk3x: Remove unlikely() annotations
  i2c: rcar: check for no IRQ in rcar_i2c_irq()
  i2c: rcar: make rcar_i2c_prepare_msg() *void*
  i2c: rcar: simplify check for last message
  i2c: designware: add support of platform data to set I2C mode
  i2c: designware: add support of I2C standard mode
2014-10-19 12:50:44 -07:00
Alexandru M Stan cf27020d2f i2c: rk3x: fix 0 length write transfers
i2cdetect -q was broken (everything was a false positive, and no transfers were
actually being sent over i2c). The way it works is by sending a 0 length write
request and checking for NACK. This patch fixes the 0 length writes and actually
sends them.

Reported-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Alexandru M Stan <amstan@chromium.org>
Tested-by: Doug Anderson <dianders@chromium.org>
Tested-by: Max Schwarz <max.schwarz@online.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2014-10-03 03:18:53 +02:00
Doug Anderson 29209338b2 i2c: rk3x: Remove unlikely() annotations
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: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-09-29 22:41:18 +02:00
addy ke b4a7bd7a38 i2c: rk3x: fix divisor calculation for SCL frequency
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: Addy Ke <addy.ke@rock-chips.com>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2014-09-20 18:35:10 +02:00
addy ke 5da4309f9e i2c: rk3x: fix bug that cause transfer fails in master receive mode
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: Addy Ke <addy.ke@rock-chips.com>
Acked-by: Max Schwarz <max.schwarz@online.de>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2014-09-02 14:29:28 +02:00
addy ke 9c5f7cad3a i2c: rk3x: fix interrupt handling issue
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: Addy Ke <addy.ke@rock-chips.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2014-08-08 18:33:57 +02:00
Dan Carpenter c51bd6acf5 i2c: rk3x: add NULL entry to the end of_device_id array
drivers/i2c/busses/i2c-rk3x.c:610:69-70: rk3x_i2c_match is not NULL terminated at line 610

Make sure of_device_id tables are NULL terminated
Generated by: /kbuild/src/linux/scripts/coccinelle/misc/of_table.cocci

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-12 23:56:37 +02:00
Max Schwarz c41aa3ce93 i2c: rk3x: add driver for Rockchip RK3xxx SoC I2C adapter
Driver for the native I2C adapter found in Rockchip RK3xxx SoCs.

Configuration is only possible through devicetree. The driver is
interrupt driven and supports the I2C_M_IGNORE_NAK mangling bit.

Signed-off-by: Max Schwarz <max.schwarz@online.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-12 00:23:56 +02:00