Probe deferral is a normal operating condition in the probe function,
so don't spam the log with an error in this case.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Pull i2c updates from Wolfram Sang:
- the core has now a lockless variant of i2c_smbus_xfer. Some open
coded versions of this got removed in drivers. This also enables
proper SCCB support in regmap.
- locking got a more precise naming. i2c_{un}lock_adapter() had to go,
and we know use i2c_lock_bus() consistently with flags like
I2C_LOCK_ROOT_ADAPTER and I2C_LOCK_SEGMENT to avoid ambiguity.
- the gpio fault injector got a new delicate testcase
- the bus recovery procedure got fixed to handle the new testcase
correctly
- a new quirk flag for controllers not able to handle zero length
messages together with driver updates to use it
- new drivers: FSI bus attached I2C masters, GENI I2C controller, Owl
family S900
- and a good set of driver improvements and bugfixes
* 'i2c/for-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (77 commits)
i2c: rcar: implement STOP and REP_START according to docs
i2c: rcar: refactor private flags
i2c: core: ACPI: Make acpi_gsb_i2c_read_bytes() check i2c_transfer return value
i2c: core: ACPI: Properly set status byte to 0 for multi-byte writes
dt-bindings: i2c: rcar: Add r8a774a1 support
dt-bindings: i2c: sh_mobile: Add r8a774a1 support
i2c: imx: Simplify stopped state tracking
i2c: imx: Fix race condition in dma read
i2c: pasemi: remove hardcoded bus numbers on smbus
i2c: designware: Add SPDX license tag
i2c: designware: Convert to use struct i2c_timings
i2c: core: Parse SDA hold time from firmware
i2c: designware-pcidrv: Mark expected switch fall-through
i2c: amd8111: Mark expected switch fall-through
i2c: sh_mobile: use core to detect 'no zero length read' quirk
i2c: xlr: use core to detect 'no zero length' quirk
i2c: rcar: use core to detect 'no zero length' quirk
i2c: stu300: use core to detect 'no zero length' quirk
i2c: pmcmsp: use core to detect 'no zero length' quirk
i2c: mxs: use core to detect 'no zero length' quirk
...
Always update the stopped state when busy status have been checked.
This is identical to what was done before, with the exception of error
handling.
Without this change, some errors cause the stopped state to be left in
incorrect state in i2c_imx_stop(), i2c_imx_dma_read(), i2c_imx_read() and
i2c_imx_xfer().
Signed-off-by: Esben Haabendal <eha@deif.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This fixes a race condition, where the DMAEN bit ends up being set after
I2C slave has transmitted a byte following the dummy read. When that
happens, an interrupt is generated instead, and no DMA request is generated
to kickstart the DMA read, and a timeout happens after DMA_TIMEOUT (1 sec).
Fixed by setting the DMAEN bit before the dummy read.
Signed-off-by: Esben Haabendal <eha@deif.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
I2C is open drain, so request the GPIO accordingly, even if pinmux did
set it up correctly for in-kernel users in this case.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Make sure to call reinit_completion() before dma is started to avoid race
condition where reinit_completion() is called after complete() and before
wait_for_completion_timeout().
Signed-off-by: Esben Haabendal <eha@deif.com>
Fixes: ce1a78840f ("i2c: imx: add DMA support for freescale i2c driver")
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
Because it looks neater.
For diolan, this allows factoring out some code that is now common
between if and else.
For eg20t, pch_i2c_writebytes is always called with a write in
msgs->flags, and pch_i2c_readbytes with a read.
For imx, i2c_imx_dma_write and i2c_imx_write are always called with a
write in msgs->flags, and i2c_imx_read with a read.
For qup, qup_i2c_write_tx_fifo_v1 is always called with a write in
qup->msg->flags.
For stu300, also restructure debug output for resends, since that
code as a result is only handling debug output.
Reviewed-by: Guenter Roeck <linux@roeck-us.net> [diolan]
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> [efm32 and imx]
Acked-by: Linus Walleij <linus.walleij@linaro.org> [stu300]
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This is unsafe, as the runtime PM callbacks are called from the PM
workqueue, so this may deadlock when handling an i2c attached clock,
which may already hold the clk_prepare mutex from another context.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Instead of repeatedly calling clk_get_rate for each transfer, register
a clock notifier to update the cached divider value each time the clock
rate actually changes.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
<linux/of_gpio.h> is not used in this file, by
<linux/gpio/consumer.h> is.
Someone is just lucky with their implicit includes.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
When converting to GPIOD, the GPIO directions of SCL/SDA have been
swapped. Fix it!
Fixes: ad36a27959 ("i2c: imx: switch to using gpiod for bus recovery gpios")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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>
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>
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>
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>
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>
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
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>
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>
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>
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>
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>
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>
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>
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
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>
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>
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>
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>
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>
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>
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>
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
...
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>