Commit Graph

88 Commits

Author SHA1 Message Date
Phil Reid
ad36a27959 i2c: imx: switch to using gpiod for bus recovery gpios
Change the driver to use the gpio descriptors for the bus recovery
information instead of the deprecated integer interface.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-27 18:39:45 +01:00
Clemens Gruber
eba523b468 i2c: imx: fix misleading bus recovery debug message
The arguments for SDA and SCL were swapped. Fix it.

Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-10-13 21:05:55 +02:00
Wei Jinhua
df0a2fdab0 i2c: imx: use IRQF_SHARED mode to request IRQ
Some SoC share one irq number between I2C controllers.
For example, on the LS2088 board, I2C 1 and I2C 2 share
one irq number. In this case, only one I2C controller
can register successfully, and others will fail.

Signed-off-by: Wei Jinhua <wei.jinhua1@zte.com.cn>
Reviewed-by: Jiang Biao <jiang.biao2@zte.com.cn>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-10-13 21:05:51 +02:00
Michail Georgios Etairidis
6c782a5ea5 i2c: imx: Use correct function to write to register
The i2c-imx driver incorrectly uses readb()/writeb() to read and
write to the appropriate registers when performing a repeated start.
The appropriate imx_i2c_read_reg()/imx_i2c_write_reg() functions
should be used instead. Performing a repeated start results in
a kernel panic. The platform is imx.

Signed-off-by: Michail G Etairidis <m.etairidis@beck-ipc.com>
Fixes: ce1a78840f ("i2c: imx: add DMA support for freescale i2c driver")
Fixes: 054b62d9f2 ("i2c: imx: fix the i2c bus hang issue when do repeat restart")
Acked-by: Fugang Duan <fugang.duan@nxp.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-06-22 10:52:02 +02:00
Bhumika Goyal
92d9d0dfb0 i2c: busses: constify i2c_algorithm structures
Declare i2c_algorithm structures as const as they are only stored in the
algo field of an i2c_adapter structure. This field is of type const, so
i2c_algorithm structures having this property can be made const too.

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> for
Acked-by: Patrice Chotard <patrice.chotard@st.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-02-09 17:06:52 +01:00
Stefan Agner
533169d164 i2c: imx: defer probe if bus recovery GPIOs are not ready
Some SoC might load the GPIO driver after the I2C driver and
using the I2C bus recovery mechanism via GPIOs. In this case
it is crucial to defer probing if the GPIO request functions
do so, otherwise the I2C driver gets loaded without recovery
mechanisms enabled.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Li Yang <leoyang.li@nxp.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2016-10-25 12:15:00 +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
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
Oleksij Rempel
2b899f34e1 i2c: imx: reduce load by using usleep_range instead of udelay
Documentation/timers/timers-howto.txt recommends to use
usleep_range on delays > 10usec. According to my test results
with Neonode zForce touchscreen driver, usleep_range indeed
reduces CPU load.

Stats collected with "./perf record -a -g -F 1000 sleep 10"

i2c-imx with udelay(50):
34.19% 0.00% irq/220-Neonode [kernel.kallsyms] [k] irq_thread
    ---irq_thread
       |--33.75%--irq_thread_fn
       |    |--19.27%--0x7f08a878
       |    |     i2c_master_recv
       |    |     i2c_transfer
       |    |     __i2c_transfer
       |    |     i2c_imx_xfer
       |    |     |--11.71%--i2c_imx_trx_complete
       |    |     |--5.70%--i2c_imx_start <<<<----------------
       |    |     |     |--5.38%--__timer_const_udelay
       |    |     |     |      __timer_delay
       |    |     |     |      --5.07%--read_current_timer

i2c-imx with usleep_range(50,100)
29.08% 0.00% irq/220-Neonode  [kernel.kallsyms] [k] irq_thread
    ---irq_thread
       |--28.89%--irq_thread_fn
       |    |--17.21%--0x7f08a878
       |    |     i2c_master_recv
       |    |     |--17.14%--i2c_transfer
       |    |     |     __i2c_transfer
       |    |     |     i2c_imx_xfer
       |    |     |     |--14.29%--i2c_imx_trx_complete
       |    |     |     |--1.42%--i2c_imx_start <<<<----------
       |    |     |     |      |--0.71%--usleep_range
       |    |     |     |      |--0.53%--i2c_imx_bus_busy

Signed-off-by: Oleksij Rempel <linux@rempel-privat.de>
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Reviewed-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-04-26 23:34:09 +02:00
Dmitriy Baranov
3bf58bb5da i2c: imx: remove extra spaces.
Signed-off-by: Dmitriy Baranov <dbaranov@dev.rtsoft.ru>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-03-03 22:31:13 +01:00
Gao Pan
c552815312 i2c: imx: fix i2c resource leak with dma transfer
In i2c_imx_dma_xfer(), when dmaengine_submit() returns error,
the context goto label err_submit and then return. However, the
memory allocated for txdesc has not been freed yet, which
leads to resource leak.

Signed-off-by: Gao Pan <b54642@freescale.com>
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-10 10:10:28 +01:00
Fabio Estevam
995e68a5ee i2c: imx: Remove unneeded comments
These multi-lines comments do not follow the standard kernel coding
style. In fact, they are not useful comments, so get rid of them.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-04 20:23:33 +01:00
Gao Pan
e8e712916c i2c: imx: improve code readability
Replace of_get_named_gpio_flags with of_get_named_gpio because
the latter has less parameters, which improves code readability.

Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Gao Pan <b54642@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-03 19:17:29 +01:00
Fabio Estevam
5b66153989 i2c: imx: Improve message log when DMA is not used
When DMA cannot be used, it is better to state that the I2C controller
will operate in PIO mode.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-03 19:11:09 +01:00
Gao Pan
588eb93ea4 i2c: imx: add runtime pm support to improve the performance
In our former i2c driver, i2c clk is enabled and disabled in
xfer function, which contributes to power saving. However,
the clk enable process brings a busy wait delay until the core
is stable. As a result, the performance is sacrificed.

To weigh the power consumption and i2c bus performance, runtime
pm is the good solution for it. The clk is enabled when a i2c
transfer starts, and disabled after a specifically defined delay.

If CONFIG_PM is disabled the net result of this patch is that the
clock is never disabled.

Without the patch the test case (many eeprom reads) executes with approx:
real 1m7.735s
user 0m0.488s
sys 0m20.040s

With the patch the same test case (many eeprom reads) executes with approx:
real 0m54.241s
user 0m0.440s
sys 0m5.920s

Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Gao Pan <b54642@freescale.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
[wsa: sorted includes]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-03 19:08:09 +01:00
Gao Pan
a5f650182b i2c: imx: init bus recovery info before adding i2c adapter
During driver probe, i2c_imx_init_recovery_info() must come before
i2c_add_numbered_adapter(), because the get/set_scl() functions
are assigned in i2c_register_adapter() under the conditon that bus
recover_info are initialized. Otherwise, get/set_scl() function
pointers never get assigned.

In such case, when i2c_generic_gpio_recovery() is used for bus recovery,
there will be kernel crash because bri->set_scl is NULL.

The solution to this bug is moving i2c_imx_init_recovery_info() before
i2c_register_adapter().

Signed-off-by: Gao Pan <b54642@freescale.com>
Signed-off-by: Fugang Duan <B38611@freescale.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2016-01-03 19:06:50 +01:00
Hou Zhiqiang
8bb6fd585d i2c: imx: fix a compiling error
drivers/i2c/busses/i2c-imx.c:978:2: error: implicit declaration of
function ‘pinctrl_select_state’ [-Werror=implicit-function-declaration]
  pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_gpio);
  ^

Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-11-20 15:58:22 +01:00
Fabio Estevam
4c0657ae43 i2c: imx: Use -ENXIO as error in the NACK case
According to Documentation/i2c/fault-codes the response to a bus NACK
should be -ENXIO, so fix the error code.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-23 22:25:33 +02:00
Gao Pan
1c4b6c3bcf i2c: imx: implement bus recovery
Implement bus recovery methods for i2c-imx so we can recover from
situations where SCL/SDA are stuck low.

Once i2c bus SCL/SDA are stuck low during transfer, config the i2c
pinctrl to gpio mode by calling pinctrl sleep set function, and then
use GPIO to emulate the i2c protocol to send nine dummy clock to recover
i2c device. After recovery, set i2c pinctrl to default group setting.

Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Gao Pan <b54642@freescale.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-23 21:55:50 +02:00
Krzysztof Kozlowski
e9a02a3d89 i2c: constify platform_device_id
The platform_device_id is not modified by these drivers and core uses it
as const.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-05-12 18:27:48 +02:00
Nicholas Mc Guire
1ac63fef05 i2c: imx: match return type of wait_for_completion_timeout
return type of wait_for_completion_timeout is unsigned long not int.
An appropriate variable of type unsigned long is introduced and the
assignments fixed up.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-15 10:50:28 +01:00
Philipp Zabel
4e355f5128 i2c: imx: whitespace and checkpatch cleanup
This patch fixes up some whitespace issues and addresses a few
checkpatch warnings.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-22 16:34:39 +01:00
Philipp Zabel
90ebd0eb06 i2c: imx: remove unused return value assignments
The ret variable is set and never used in the error path of i2c_imx_dma_request.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-14 15:18:51 +01:00
Nicholas Mc Guire
cb9eaba4c5 i2c: imx: fix handling of wait_for_completion_timeout result
wait_for_completion_timeout does not return negative values so
"result" handling here should be simplified to cover the actually
possible cases only.

Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-13 16:21:07 +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
Wolfram Sang
f508493367 i2c: imx: simplify i2c_imx_dma_write() a little
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Yao Yuan <yao.yuan@freescale.com>
2014-11-19 15:16:19 +01:00
Yao Yuan
ce1a78840f i2c: imx: add DMA support for freescale i2c driver
Add dma support for i2c. This function depend on DMA driver.
You can turn on it by write both the dmas and dma-name properties in dts node.
DMA is optional, even DMA request unsuccessfully, i2c can also work well.

Signed-off-by: Yuan Yao <yao.yuan@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-18 16:01:27 +01:00
Yao Yuan
2fbed5119d i2c: imx: Sort include headers alphabetically
If the inlcude headers aren't sorted alphabetically, then the
logical choice is to append new ones, however that creates a
lot of potential for conflicts or duplicates because every change
will then add new includes in the same location.

Signed-off-by: Yuan Yao <yao.yuan@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-18 15:52:52 +01:00
Fabio Estevam
d4ffeecb3b i2c: imx+mxs: Use the preferred form for passing a size of a struct
According to Documentation/CodingStyle - Chapter 14:

"The preferred form for passing a size of a struct is the following:

	p = kmalloc(sizeof(*p), ...);

The alternative form where struct name is spelled out hurts readability and
introduces an opportunity for a bug when the pointer variable type is changed
but the corresponding sizeof that is passed to a memory allocator is not."

So do it as recommeded.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-10 09:34:54 +01:00
Wolfram Sang
ca1f8da9ac i2c: remove FSF address
We have a central copy of the GPL for that. Some addresses were already
outdated.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2014-11-07 18:35:33 +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
Fabio Estevam
a4ce47f108 i2c-imx: Disable the clock on probe failure
In the case of errors during probe, we should disable i2c_imx->clk.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-10-06 19:59:55 +02:00
Haibo Chen
639a26cf07 i2c: imx: Add arbitration lost check
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: Haibo Chen <haibo.chen@freescale.com>
Acked-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-09-29 22:41:18 +02:00
Xiubo Li
64bdfbfc76 i2c: imx: Fix format warning for dev_dbg
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: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-08-06 20:58:50 +02:00
Jingoo Han
46797a2adb i2c: remove unnecessary OOM messages
The site-specific OOM messages are unnecessary, because they
duplicate the MM subsystem generic OOM message. For example,
k.alloc and v.alloc failures use dump_stack().

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Felipe Balbi <balbi@ti.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-02 19:24:33 +02:00
Fugang Duan
9b2a6da33c i2c: imx: update i2c clock divider for each transaction
Since IMX serial SOCs support low bus freq mode, some clocks freq
may change to save power. I2C needs to check the clock source and
update the divider.

For example:
i.MX6SL I2C clk is from IPG_PERCLK which is sourced from IPG_CLK.
Under normal operation, IPG_CLK is 66MHz, ipg_perclk is at 22MHz.
In low bus freq mode, IPG_CLK is at 12MHz and IPG_PERCLK is down
to 4MHz. So the I2C driver must update the divider register for
each transaction when the current IPG_PERCLK is not equal to the
clock of previous transaction.

Signed-off-by: Fugang Duan  <B38611@freescale.com>
[wsa: removed an outdated comment and simplified debug output]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-02 19:18:33 +02:00
Fugang Duan
054b62d9f2 i2c: imx: fix the i2c bus hang issue when do repeat restart
Test i2c device Maxim max44009, datasheet is located at:
http://www.maximintegrated.com/datasheet/index.mvp/id/7175

The max44009 support repeat operation like:
read -> repeat restart -> read/write

The current i2c imx host controller driver don't support this
operation that causes i2c bus hang due to "MTX" is cleared in
.i2c_imx_read(). If "read" is the last message there have no problem,
so the current driver supports all SMbus operation like:
write -> repeat restart -> read/write

IMX i2c controller for master receiver has some limitation:
- If it is the last byte for one operation, it must generate STOP
  signal before read I2DR to prevent controller from generating another
  clock cycle.
- If it is the last byte in the read, and then do repeat restart, it must
  set "MTX" before read I2DR to prevent controller from generating another
  extra clock cycle.

The patch is to fix the issue.

Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-02 19:18:18 +02:00
Kaushal Butala
8e8782c715 i2c: imx: add SMBus block read support
The smbus block read is not currently supported for imx i2c devices.
This patchset adds the support to imx i2c bus so that blocks of data
can be read using SMbus block reads.(using i2c_smbus_read_block_data()
function from the i2c_core.c.). Tested with 3.10.9 kernel.

Reviewed-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Kaushal Butala <kaushalkernelmailinglist@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-05-22 10:09:21 +02:00
Wolfram Sang
a8763f33c5 i2c: imx: propagate irq error code in probe
smatch rightfully says:
drivers/i2c/busses/i2c-imx.c:610 i2c_imx_probe() info: why not propagate 'irq' from platform_get_irq() instead of (-2)?

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-01-03 17:40:38 +01:00
Fabio Estevam
e5bf216a94 i2c: imx: Check the return value from clk_prepare_enable()
clk_prepare_enable() may fail, so let's check its return value and propagate it
in the case of error.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-12-12 22:48:22 +01:00
Wolfram Sang
3611431ce7 i2c: i2c-imx: replace platform_driver_probe to support deferred probing
Subsystems like pinctrl and gpio rightfully make use of deferred probing at
core level. Now, deferred drivers won't be retried if they don't have a .probe
function specified in the driver struct. Fix this driver to have that, so the
devices it supports won't get lost in a deferred probe.

Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-10-10 10:22:29 +02:00
Wolfram Sang
687b81d083 i2c: move OF helpers into the core
I2C of helpers used to live in of_i2c.c but experience (from SPI) shows
that it is much cleaner to have this in the core. This also removes a
circular dependency between the helpers and the core, and so we can
finally register child nodes in the core instead of doing this manually
in each driver. So, fix the drivers and documentation, too.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-23 10:22:20 +02:00
Jingoo Han
6d4028c644 i2c: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-19 19:46:30 +02:00
Jingchang Lu
ad90efae1b i2c: imx: Add Vybrid VF610 I2C controller support
Add Freescale Vybrid VF610 I2C controller support to
imx I2C driver framework.

Signed-off-by: Jason Jin <Jason.jin@freescale.com>
Signed-off-by: Jingchang Lu <b35083@freescale.com>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-15 16:14:50 +02:00
Jingchang Lu
4b775022f6 i2c: imx: add struct to hold more configurable quirks
This add struct imx_i2c_hwdata to hold more quirks data
which may vary between SoCs, thus the driver can operate
on more differences to support more SoCs.

Signed-off-by: Jingchang Lu <b35083@freescale.com>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-15 16:14:19 +02:00
Jingchang Lu
171408c211 i2c: imx: add INT flag and IEN bit operatation codes
This add bits operation macro that differ between SoCs.
Interrupt flags clear operation in I2SR differ between SoCs:
write zero to clear(w0c) INT flag on i.MX,
but write one to clear(w1c) INT flag on Vybrid.
I2C module enable operation in I2CR also differ between SoCs:
set I2CR_IEN bit enable the module on i.MX,
but clear I2CR_IEN bit enable the module on Vybrid.

Signed-off-by: Jingchang Lu <b35083@freescale.com>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-15 16:13:48 +02:00
Jingchang Lu
8cc7331ff3 i2c: imx: change register offset representation
the I2C register offset may different between SoCs,
to provid support for all these chips, split the
register offset into a fixed base address and a
variable shift value, then the full register offset
will be calculated by
reg_off = ( reg_base_addr << reg_shift)

Signed-off-by: Jingchang Lu <b35083@freescale.com>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-15 16:13:17 +02:00
Jingchang Lu
1d5ef2a83e i2c: imx: wrap registers read/write to inline function
wrap the readb(), writeb() into inline function calls.
It would make the driver more clearer to support platform
with different register offset.

Signed-off-by: Jingchang Lu <b35083@freescale.com>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-15 16:12:47 +02:00
Jingchang Lu
0fc1347a7f i2c: imx: don't change platform device id_entry directly
The id_entry field should be changed by platform driver core,
driver should prevent changing it derectly. Use local variable
to save and extract platform_device_id info of the dts devices
instead.

Signed-off-by: Jingchang Lu <b35083@freescale.com>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-15 16:12:14 +02:00
Jingchang Lu
46f2832b9f i2c: imx: enable clk before write to registers
The module clk should be enabled before write to
its register in probe(), and the clk can be disabled
after.

Signed-off-by: Jingchang Lu <b35083@freescale.com>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-15 16:11:41 +02:00