We found that after commit 9c46929e79
("ARM: implement THREAD_INFO_IN_TASK for uniprocessor systems"), the
PCF85063 RTC driver stopped working on i.MX28 due to regmap_bulk_read()
reading bogus data into a stack buffer. This is caused by the i2c-mxs
driver using DMA transfers even for messages without the I2C_M_DMA_SAFE
flag, and the aforementioned commit enabling vmapped stacks.
As the MXS I2C controller requires DMA for reads of >4 bytes, DMA can't be
disabled, so the issue is fixed by using i2c_get_dma_safe_msg_buf() to
create a bounce buffer when needed.
Fixes: 9c46929e79 ("ARM: implement THREAD_INFO_IN_TASK for uniprocessor systems")
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
During boot of I2SE Duckbill the kernel log contains a
confusing error:
Failed to request dma
This is caused by i2c-mxs tries to request a not yet available DMA
channel (-EPROBE_DEFER). So suppress this message by using
dev_err_probe().
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Follow the advice of the below link and prefer 'strscpy'. Conversion is
easy because no driver used the return value and has been done with a
simple sed invocation.
Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Change the of_device_get_match_data() cast to (uintptr_t)
to silence the following clang warning:
drivers/i2c/busses/i2c-mxs.c:802:18: warning: cast to smaller integer type 'enum mxs_i2c_devtype' from 'const void *' [-Wvoid-pointer-to-enum-cast]
Reported-by: kernel test robot <lkp@intel.com>
Fixes: c32abd8b56 ("i2c: mxs: Remove unneeded platform_device_id")
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
dmaengine_terminate_all() is deprecated in favor of explicitly saying if
it should be sync or async. Here, we want dmaengine_terminate_sync()
because there is no other synchronization code in the driver to handle
an async case.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
The i2c-mxs driver only runs on DT-platform and there is no
need to use the platform_device_id structure to pass the driver
data.
Get rid of it to make the code simpler.
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
The driver-specific usage of the DMA_CTRL_ACK flag was replaced with a
custom flag in commit ceeeb99cd8 ("dmaengine: mxs: rename custom flag"),
but i2c-mxs was not updated to use the new flag, completely breaking I2C
transactions using DMA.
Fixes: ceeeb99cd8 ("dmaengine: mxs: rename custom flag")
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
dma_request_slave_channel() is a wrapper on top of dma_request_chan()
eating up the error code.
By using dma_request_chan() directly the driver can support deferred
probing against DMA.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Use the new helper devm_platform_ioremap_resource() which wraps the
platform_get_resource() and devm_ioremap_resource() together, to
simplify the code.
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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>
Assign true or false to boolean variables instead of an integer value.
This issue was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Instead of printing errors after mxs_i2c_pio_wait_xfer_end returns with
an error code just print a debug message.
NAKs and timeouts can occur in this situation normally, so do not treat
them as errors.
Signed-off-by: Michael Thalmeier <michael.thalmeier@hale.at>
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>
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>
My Pengutronix address is not valid anymore, redirect people to the Pengutronix
kernel team.
Reported-by: Harald Geyer <harald@ccbib.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Robert Schwebel <r.schwebel@pengutronix.de>
Return type of wait_for_completion_timeout is unsigned long not int.
An appropriately named unsigned long is added and the assignment fixed up.
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
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
...
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>
i2cdetect scanned i2c bus slow because the i2c-mxs driver ignored the
NO_SLAVE_ACK bit during busy-waiting loop. Thanks to the patch, the
speedup happens.
Signed-off-by: Janusz Uzycki <j.uzycki@elproma.com.pl>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If I2C_M_RD flag is set SELECT command is sent and afterward READ
command. The patch fixes READ command to return READ failure error
message instead of SELECT failure error message.
Signed-off-by: Janusz Uzycki <j.uzycki@elproma.com.pl>
Acked-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Use devm_ioremap_resource() in order to make the code simpler,
and remove redundant return value check of platform_get_resource()
because the value is checked by devm_ioremap_resource().
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Pull i2c changes from Wolfram Sang:
- new drivers for exynos5, bcm kona, and st micro
- bigger overhauls for drivers mxs and rcar
- typical driver bugfixes, cleanups, improvements
- got rid of the superfluous 'driver' member in i2c_client struct This
touches a few drivers in other subsystems. All acked.
* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (38 commits)
i2c: bcm-kona: fix error return code in bcm_kona_i2c_probe()
i2c: i2c-eg20t: do not print error message in syslog if no ACK received
i2c: bcm-kona: Introduce Broadcom I2C Driver
i2c: cbus-gpio: Fix device tree binding
i2c: wmt: add missing clk_disable_unprepare() on error
i2c: designware: add new ACPI IDs
i2c: i801: Add Device IDs for Intel Wildcat Point-LP PCH
i2c: exynos5: Remove incorrect clk_disable_unprepare
i2c: i2c-st: Add ST I2C controller
i2c: exynos5: add High Speed I2C controller driver
i2c: rcar: fixup rcar type naming
i2c: scmi: remove some bogus NULL checks
i2c: sh_mobile & rcar: Enable the driver on all ARM platforms
i2c: sh_mobile: Convert to clk_prepare/unprepare
i2c: mux: gpio: use reg value for i2c_add_mux_adapter
i2c: mux: gpio: use gpio_set_value_cansleep()
i2c: Include linux/of.h header
i2c: mxs: Fix PIO mode on i.MX23
i2c: mxs: Rework the PIO mode operation
i2c: mxs: distinguish i.MX23 and i.MX28 based I2C controller
...
Use this new function to make code more comprehensible, since we are
reinitialzing the completion, not initializing.
[akpm@linux-foundation.org: linux-next resyncs]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org> (personally at LCE13)
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The i.MX23 I2C controller is also capable of PIO, but needs a little harder
push to behave. The controller needs to be reset after every PIO/DMA operation
for some reason, otherwise in rare cases, the controller can hang or emit
bytes onto the bus.
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Analyze and rework the PIO mode operation. The PIO mode operation
was unreliable on MX28, by analyzing the bus with LA, the checks
for when data were available or were to be sent were wrong.
The PIO WRITE has to be completely reworked as it multiple problems.
The MX23 datasheet helped here, see comments in the code for details.
The problems boil down to:
- RUN bit in CTRL0 must be set after DATA register was written
- The PIO transfer must be 4 bytes long tops, otherwise use
clock stretching.
Both of these fixes are implemented.
The PIO READ operation can only be done for up to four bytes as
we are unable to read out the data from the DATA register fast
enough.
This patch also tries to document the investigation within the
code.
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
It seems the PIO mode does not work, or at least not like it works
on a i.MX28. Each short transfer needs about one second (without an
error message) but does not send anything on the I2C lines.
Signed-off-by: Juergen Beisert <jbe@pengutronix.de>
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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>
The timing calculation is rather bogus and gives extremely wrong
results for higher frequencies (on an i.MX28). E.g. instead of 400 kHz
I measured 770 kHz.
Implement a calculation that adheres to the I2C spec and gives exact
results for I2C frequencies from 12.56 kHz to 960 kHz.
Also the bus_free and leadin parameters are programmed according to
the I2C spec for standard and fast mode.
This was tested on a Ka-Ro TX28 module with a DS1339, TSC2007, PCA9554
and SGTL5000 client.
Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Acked-by: Marek Vasut <marex@denx.de>
[wsa: patch fixes whitespace issue, too]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
stmp_reset_block() 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>
Acked-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Recently we have been seing some reports about PIO mode not working properly.
- http://www.spinics.net/lists/linux-i2c/msg11985.html
- http://marc.info/?l=linux-i2c&m=137235593101385&w=2
- https://lkml.org/lkml/2013/6/24/430
Let's use DMA mode even for small transfers.
Without this patch, i2c reads the incorrect sgtl5000 version on a mx28evk when
touchscreen is enabled:
[ 5.856270] sgtl5000 0-000a: Device with ID register 0 is not a sgtl5000
[ 9.877307] sgtl5000 0-000a: ASoC: failed to probe CODEC -19
[ 9.883528] mxs-sgtl5000 sound.12: ASoC: failed to instantiate card -19
[ 9.892955] mxs-sgtl5000 sound.12: snd_soc_register_card failed (-19)
Cc: <stable@vger.kernel.org>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Marek Vasut <marex@denx.de>
[wsa: we have a proper solution for -next, so this non intrusive
solution is OK for now]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Since commit ab78029 (drivers/pinctrl: grab default handles from device core),
we can rely on device core for handling pinctrl.
So remove devm_pinctrl_get_select_default() from the driver.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
These are mostly new device tree bindings for existing drivers, as well
as changes to the device tree source files to add support for those
devices, and a couple of new boards, most notably Samsung's Exynos5
based Chromebook.
The changes depend on earlier platform specific updates and touch
the usual platforms: omap, exynos, tegra, mxs, mvebu and davinci.
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Merge tag 'dt-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC device tree updates (part 2) from Arnd Bergmann:
"These are mostly new device tree bindings for existing drivers, as
well as changes to the device tree source files to add support for
those devices, and a couple of new boards, most notably Samsung's
Exynos5 based Chromebook.
The changes depend on earlier platform specific updates and touch the
usual platforms: omap, exynos, tegra, mxs, mvebu and davinci."
* tag 'dt-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (169 commits)
ARM: exynos: dts: cros5250: add EC device
ARM: dts: Add sbs-battery for exynos5250-snow
ARM: dts: Add i2c-arbitrator bus for exynos5250-snow
ARM: dts: add mshc controller node for Exynos4x12 SoCs
ARM: dts: Add chip-id controller node on Exynos4/5 SoC
ARM: EXYNOS: Create virtual I/O mapping for Chip-ID controller using device tree
ARM: davinci: da850-evm: add SPI flash support
ARM: davinci: da850: override SPI DT node device name
ARM: davinci: da850: add SPI1 DT node
spi/davinci: add DT binding documentation
spi/davinci: no wildcards in DT compatible property
ARM: dts: mvebu: Convert mvebu device tree files to 64 bits
ARM: dts: mvebu: introduce internal-regs node
ARM: dts: mvebu: Convert all the mvebu files to use the range property
ARM: dts: mvebu: move all peripherals inside soc
ARM: dts: mvebu: fix cpus section indentation
ARM: davinci: da850: add EHRPWM & ECAP DT node
ARM/dts: OMAP3: fix pinctrl-single configuration
ARM: dts: Add OMAP3430 SDP NOR flash memory binding
ARM: dts: Add NOR flash bindings for OMAP2420 H4
...
In PIO mode we can end up with the same errors as in DMA mode, but as IRQs
are disabled there we have to check for them manually after each command.
Also don't use the big controller reset hammer when receiving a NAK from a
slave. It's sufficient to tell the controller to continue at a clean state.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Tested-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit fixes the three following races in PIO code:
- The CTRL0 register is racy in itself, when programming transfer state and
run bit in the same cycle the hardware sometimes ends up using the state
from the last transfer. Fix this by programming state in one cycle, make
sure the write is flushed down APBX bus by reading back the reg and only
then trigger the run bit.
- Only clear the DMAREQ bit in DEBUG0 after the read/write to the data reg
happened. Otherwise we are racing with the hardware about who touches
the data reg first.
- When checking for completion of a transfer it's not sufficient to check
if the data engine finished, but also a check for i2c bus idle is needed.
In PIO mode we are really fast to program the next transfer after a finished
one, so the controller possibly tries to start a new transfer while the
clkgen engine is still busy writing the NAK/STOP from the last transfer to
the bus.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
With the generic DMA device tree helper supported by mxs-dma driver,
client devices only need to call dma_request_slave_channel() for
requesting a DMA channel from dmaengine.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
i2c_del_adapter() always returns 0. So all checks testing whether it will be
non zero will always evaluate to false and the conditional code is dead code.
This patch updates all callers of i2c_del_mux_adapter() to ignore the return
value and assume that it will always succeed (which it will). In a subsequent
patch the return type of i2c_del_adapter() will be made void.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Ben Hutchings <bhutchings@solarflare.com>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
There is simply no reason to be manually setting the private driver
data to NULL in the remove/fail to probe cases. This is just extra
cruft code that can be removed.
A few notes:
* Nothing relies on drvdata being set to NULL.
* The __device_release_driver() function eventually calls
dev_set_drvdata(dev, NULL) anyway, so there's no need to do it
twice.
* I verified that there were no cases where xxx_get_drvdata() was
being called in these drivers and checking for / relying on the NULL
return value.
This could be cleaned up kernel-wide but for now just take the baby
step and remove from the i2c subsystem.
Reported-by: Wolfram Sang <wsa@the-dreams.de>
Reported-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
This patch drops the i2c timing tables from this driver and instead
derives the timing based from the requested clock sleep. The timing
tables were completely wrong anyway when observed on a scope.
This new algorithm is also only derived by using a scope, but it seems
to produce much more accurate result.
Signed-off-by: Marek Vasut <marex@denx.de>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
[wsa: changed messages from dev_err to dev_warn]
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
Add support for the PIO mode and mixed PIO/DMA mode support. The mixed
PIO/DMA is the default mode of operation. This shall leverage overhead
that the driver creates due to setting up DMA descriptors even for very
short transfers.
The current boundary between PIO/DMA 8 bytes, transfers shorter than 8
bytes are transfered by PIO, longer transfers use DMA. The performance
of write transfers remains unchanged, while there is a minor improvement
of read performance. Reading 16KB EEPROM with DMA-only operations gives
a read speed of 39.5KB/s, while with then new mixed-mode the speed is
blazing 40.6KB/s.
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
cmd_err is used to handle error code, so it should not be unsigned.
This fixes the following warning when building with W=1 option:
drivers/i2c/busses/i2c-mxs.c: In function 'mxs_i2c_xfer_msg':
drivers/i2c/busses/i2c-mxs.c:331:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: stable@kernel.org
The init_completion() call does reinit not only the variable carrying
the flag that the completion finished, but also initialized the
waitqueue associated with the completion. On the contrary, the
INIT_COMPLETION() call only reinits the flag.
In case there was anything still stuck in the waitqueue, subsequent call
to init_completion() would be able to create possible race condition. This
patch uses the proper function and moves init_completion() into .probe() call
of the driver, to be issued only once.
Note that such scenario is impossible, since two threads can never enter the
mxs_i2c_xfer_msg(), since whole this section is protected by mutex in I2C core.
This by no means allows this issue to exit though.
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
CONFIG_HOTPLUG is going away as an option. As result the __dev*
markings will be going away.
Remove use of __devinit, __devexit_p, __devinitdata, __devinitconst,
and __devexit.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com> (for ocores and mux-gpio)
Acked-by: Havard Skinnemoen <hskinnemoen@gmail.com> (for i2c-gpio)
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> (for puf3)
Acked-by: Barry Song <baohua.song@csr.com> (for sirf)
Reviewed-by: Jean Delvare <khali@linux-fr.org>
[wsa: Fixed "foo* bar" flaws while we are here]
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
There is no reason to disable the I2C SMBus quick mode on this
IP block. Enable it. This essentially fixes the problem with the
"i2c-detect" command for probing the bus.
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Properly terminate the DMA transfer in case the DMA PIO transfer
or setup fails for any reason.
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
This I2C master can do DMA and PIOQUEUE (PIO with FIFO). Originally,
only PIOQUEUE was supported and it had issues, then DMA support was added
this cycle. The original intention was to keep PIOQUEUE since it has
less overhead what is nice for small transfers. However, runtime
switching between PIOQEUE and DMA depending on the transfer size never
worked despite a lot of trying. Since PIOQUEUE mode itself was flaky
(polling at places where interrupts failed to work) and the
implementation also imposed a size limit for transfers, it is best to
remove the support, so users don't fall over its limitations. It also
makes the driver a lot cleaner and more robust. If somebody really wants
less overhead, plain PIO mode could still be implemented with the
addidtional advantage that this mode is also available on MX23, too.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Reviewed-by: Marek Vasut <marex@denx.de>
Matthias Schiffer
Stefan Wahren
Wolfram Sang
Fabio Estevam
Andy Shevchenko
Peter Ujfalusi
Anson Huang
Fabio Estevam
Peter Rosin
Gustavo A. R. Silva
Michael Thalmeier
Wolfram Sang
Krzysztof Kozlowski
Wolfram Sang
Nicholas Mc Guire
Linus Torvalds
Fabio Estevam
Janusz Użycki
Jingoo Han
Marek Vasut
Juergen Beisert
Lothar Waßmann
Lucas Stach
Shawn Guo
Lars-Peter Clausen
Doug Anderson
Bill Pemberton
Wolfram Sang