commit fba4adbbf6 upstream.
One I2C bus on my Atom E3845 board has been broken since 4.9.
It has two devices, both declared by ACPI and with built-in drivers.
There are two back-to-back transactions originating from the kernel, one
targeting each device. The first transaction works, the second one locks
up the I2C controller. The controller never recovers.
These kernel logs show up whenever an I2C transaction is attempted after
this failure.
i2c-designware-pci 0000:00:18.3: timeout in disabling adapter
i2c-designware-pci 0000:00:18.3: timeout waiting for bus ready
Waiting for the I2C controller status to indicate that it is enabled
before programming it fixes the issue.
I have tested this patch on 4.14 and 4.15.
Fixes: commit 2702ea7dbe ("i2c: designware: wait for disable/enable only if necessary")
Cc: linux-stable <stable@vger.kernel.org> #4.13+
Signed-off-by: Ben Gardner <gardner.ben@gmail.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Ben Gardner <gardner.ben@gmail.com>
[Jarkko: Backported to v4.9..v4.12 before i2c-designware-core.c was renamed to i2c-designware-master.c]
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 12688dc21f upstream.
This reverts commit 63d0f0a695.
It caused a regression on platforms where I2C controller is synthesized
with dynamic TAR update disabled. Detection code is testing is bit
DW_IC_CON_10BITADDR_MASTER in register DW_IC_CON read-only but fails to
restore original value in case bit is read-write.
Instead of fixing this we revert the commit since it was preparation for
the commit 0317e6c0f1 ("i2c: designware: do not disable adapter after
transfer") which was also reverted.
Reported-by: Shah Nehal-Bakulchandra <Nehal-bakulchandra.Shah@amd.com>
Reported-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Acked-By: Lucas De Marchi <lucas.demarchi@intel.com>
Fixes: 63d0f0a695 ("i2c: designware: detect when dynamic tar update is possible")
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 0317e6c0f1.
Srinivas reported recently touchscreen and touchpad stopped working in
Haswell based machine in Linux 4.9-rc series with timeout errors from
i2c_designware:
[ 16.508013] i2c_designware INT33C3:00: controller timed out
[ 16.508302] i2c_hid i2c-MSFT0001:02: failed to change power setting.
[ 17.532016] i2c_designware INT33C3:00: controller timed out
[ 18.556022] i2c_designware INT33C3:00: controller timed out
[ 18.556315] i2c_hid i2c-ATML1000:00: failed to retrieve report from device.
I managed to reproduce similar errors on another Haswell based machine
where touchscreen initialization fails maybe in every 1/5 - 1/2 boots.
Since root cause for these errors is not clear yet and debugging is
ongoing it's better to revert this commit as we are near to release.
Reported-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
When loading the TX fifo to receive bytes on the I2C bus, we incorrectly
count the number of bytes:
rx_limit = dev->rx_fifo_depth - dw_readl(dev, DW_IC_RXFLR);
while (buf_len > 0 && tx_limit > 0 && rx_limit > 0) {
if (rx_limit - dev->rx_outstanding <= 0)
break;
rx_limit--;
dev->rx_outstanding++;
}
DW_IC_RXFLR indicates how many bytes are available to be read in the
FIFO, dev->rx_fifo_depth is the FIFO size, and dev->rx_outstanding is
the number of bytes that we've requested to be read so far, but which
have not been read.
Firstly, increasing dev->rx_outstanding and decreasing rx_limit and then
comparing them results in each byte consuming "two" bytes in this
tracking, so this is obviously wrong.
Secondly, the number of bytes that _could_ be received into the FIFO at
any time is the number of bytes we have so far requested but not yet
read from the FIFO - in other words dev->rx_outstanding.
So, in order to request enough bytes to fill the RX FIFO, we need to
request dev->rx_fifo_depth - dev->rx_outstanding bytes.
Modifying the code thusly results in us reaching the maximum number of
bytes outstanding each time we queue more "receive" operations, provided
the transfer allows that to happen.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Rather than reporting success for a short transfer due to interrupt
latency, report an error both to the caller, as well as to the kernel
log.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
I2C DesignWare may abort transfer with arbitration lost if I2C slave pulls
SDA down quickly after falling edge of SCL. Reason for this is unknown but
after trial and error it was found this can be avoided by enabling non-zero
SDA RX hold time for the receiver.
By the specification SDA RX hold time extends incoming SDA low to high
transition by n * ic_clk cycles but only when SCL is high. However it
seems to help avoid above faulty arbitration lost error.
Bits 23:16 in IC_SDA_HOLD register define the SDA RX hold time for the
receiver. Be conservative and enable 1 ic_clk cycle long hold time in
case boot firmware hasn't set it up.
Reported-by: Jukka Laitinen <jukka.laitinen@intel.com>
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Jukka Laitinen <jukka.laitinen@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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
...
There are several ways to set the SDA hold time for i2c controller,
including: Device Tree, built-in device properties and ACPI. However,
if the SDA hold time is not specified by above method, we should
read the value, where it is preset by firmware, and save it to
sda_hold_time. This is needed because when i2c controller enters
runtime suspend, the DW_IC_SDA_HOLD value will be reset to chipset
default value. And during runtime resume, i2c_dw_init will be called
to reconfigure i2c controller. If sda_hold_time is zero, the chipset
default hold time will be used, that will be too short for some
platforms. Therefore, to have a better tolerance, the DW_IC_SDA_HOLD
value should be kept by sda_hold_time.
Signed-off-by: Zhuo-hao Lee <zhuo-hao.lee@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Disabling the adapter after each transfer adds additional delays
for each I2C transfer. Even if we don't wait for it to be disabled
anymore, on next transfer we will need to if we have several transfers
in a row.
Now during the transfer init we check if IC_TAR can be changed
dynamically, the status register for no activity and TX buffer being
empty. In this case we don't need to disable it
When a transfer fails the adapter will still be disabled - this is a
conservative approach. When transfers succeed, the adapter is left
enabled and it's configured so to disable interrupts.
Alternating register reads on 2 slaves:
perf stat -r4 chrt -f 10 ./i2c-test /dev/i2c-1 25000 0x40 0x6 0x1e 0x00
Before:
8.638705161 seconds time elapsed ( +- 5.90% )
After:
7.516821591 seconds time elapsed ( +- 0.11% )
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Christian Ruppert <christian.ruppert@alitech.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This adapter can be synthesized with dynamic tar update enabled or disabled.
When enabled it is not necessary to disable the adapter to change the slave
address in some situations, which saves some time per transaction.
There is no direct register to know if this feature is enabled but we can do it
indirectly by writing to the 10BIT_ADDR field in IC_CON: this field is
read only when dynamic tar update is enabled.
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Christian Ruppert <christian.ruppert@alitech.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
These are used in 2 places and will be needed in more.
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Christian Ruppert <christian.ruppert@alitech.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If we aren't going to continue using the controller we can just disable
it instead of waiting for it to complete. The biggest improvement here
is when a I2C transaction is completed and it doesn't block until
the adapter is disabled. When a new transfer is needed we will disable
and wait for its completion.
This way the adapter will continue changing its state in parallel to the
execution of the thread that requested the I2C transaction saving most
of the time 25~250 usec per I2C transaction.
A simple program doing a register read (1 byte write, 1 byte read)
alternating on 2 different slaves repeated 25k times for each and
measurements taken 4 times we get:
perf stat -r4 chrt -f 10 ./i2c-test /dev/i2c-1 25000 0x40 0x6 0x1e 0x00
Before:
30.879317977 seconds time elapsed ( +- 14.83% )
After:
8.638705161 seconds time elapsed ( +- 5.90% )
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Christian Ruppert <christian.ruppert@alitech.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This patch enabled high speed mode. High speed mode can be turn on by
setting the clk_freq to 3400000. High speed HCNT and LCNT are needed
as there is no default value provided.
Signed-off-by: Weifeng Voon <weifeng.voon@intel.com>
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This patch enabled fast mode plus. The fast mode plus and fast speed
share the same HCNT and LCNT register. So, the fast mode plus will only
run when the HCNT and LCNT value is provided. Else, it will run at fast
speed as default.
Signed-off-by: Weifeng Voon <weifeng.voon@intel.com>
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This allows applications to set the transfer timeout in 10ms increments via
ioctl I2C_TIMEOUT.
Signed-off-by: Weifeng Voon <weifeng.voon@intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
There can be unnecessary runtime suspend-resume cycle during
i2c-designware-platdrv probe when it registers the I2C adapter device. This
happens because i2c-designware-platdrv is set to initially active platform
device in its probe function and is a parent of I2C adapter.
In that case power.usage_count of i2c-designware device is zero and
pm_runtime_get()/pm_runtime_put() cycle during probe could put it into
runtime suspend. This happens when the i2c_register_adapter() calls the
device_register():
i2c_register_adapter
device_register
device_add
bus_probe_device
device_initial_probe
__device_attach
if (dev->parent) pm_runtime_get_sync(dev->parent)
...
if (dev->parent) pm_runtime_put(dev->parent)
After that the i2c_register_adapter() continues registering I2C slave
devices. In case slave device probe does I2C transfers the parent will
resume again and thus get a needless runtime suspend/resume cycle during
adapter registration.
Prevent this while retaining the runtime PM status of i2c-designware by
only incrementing/decrementing device power usage count during I2C
adapter registration. That makes sure there won't be spurious runtime PM
status changes and lets the driver core to idle the device after probe
finishes.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The per adapter bus_lock already projects from concurrent calls to the
master_xfer callback. No need to add a driver internal lock.
Also, rephrase a comment to drop mention of this lock.
Reported-by: Rongrong Zou <zourongrong@gmail.com>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This is effectively reapplies the commit b0898fdaff ("i2c: designware-pci: use
IRQF_COND_SUSPEND flag") after the commit d80d134182 ("i2c: designware: Move
common probe code into i2c_dw_probe()"). Original message as follows.
The mentioned flag fixes a warning on Intel Edison board since one of the I2C
controller shares IRQ line with watchdog timer.
Fixes: d80d134182 (i2c: designware: Move common probe code into i2c_dw_probe())
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Pull i2c updates from Wolfram Sang:
"Quite some driver updates:
- piix4 can now handle multiplexed adapters
- brcmstb, xlr, eg20t, designware drivers support more SoCs
- emev2 gained i2c slave support
- img-scb and rcar got bigger refactoring to remove issues
- lots of common driver updates
i2c core changes:
- new quirk flag when an adapter does not support clock stretching,
so clients can be configured to avoid that if possible
- added a helper function to retrieve timing parameters from firmware
(with rcar being the first user)
- "multi-master" DT binding added so drivers can adapt to this
setting (like disabling PM to keep arbitration working)
- RuntimePM for the logical adapter device is now always enabled by
the core to ensure propagation from childs to the parent (the HW
device)
- new macro builtin_i2c_driver to reduce boilerplate"
* 'i2c/for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (70 commits)
i2c: create builtin_i2c_driver to avoid registration boilerplate
i2c: imx: fix i2c resource leak with dma transfer
dt-bindings: i2c: eeprom: add another EEPROM device
dt-bindings: move I2C eeprom descriptions to the proper file
i2c: designware: Do not require clock when SSCN and FFCN are provided
DT: i2c: trivial-devices: Add Epson RX8010 and MPL3115
i2c: s3c2410: remove superfluous runtime PM calls
i2c: always enable RuntimePM for the adapter device
i2c: designware: retry transfer on transient failure
i2c: ibm_iic: rename i2c_timings struct due to clash with generic version
i2c: designware: Add support for AMD Seattle I2C
i2c: imx: Remove unneeded comments
i2c: st: use to_platform_device()
i2c: designware: use to_pci_dev()
i2c: brcmstb: Adding support for CM and DSL SoCs
i2c: mediatek: fix i2c multi transfer issue in high speed mode
i2c: imx: improve code readability
i2c: imx: Improve message log when DMA is not used
i2c: imx: add runtime pm support to improve the performance
i2c: imx: init bus recovery info before adding i2c adapter
...
The current driver uses input clock source frequency to calculate
values for [SS|FS]_[HC|LC] registers. However, when booting ACPI, we do not
currently have a good way to provide the frequency information.
Instead, we can leverage the SSCN and FFCN ACPI methods, which can be used
to directly provide these values. So, the clock information should
no longer be required during probing.
However, since clk can be invalid, additional checks must be done where
we are making use of it.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Tested-by: Loc Ho <lho@apm.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Set the i2c_adapter retries field to a sensible value. This allows the i2c core
to retry master_xfer() when it returns -EAGAIN. Currently the i2c-designware
driver returns -EAGAIN only on Tx arbitration failure (DW_IC_TX_ARB_LOST).
Reported-by: Rolland Chau <zourongrong@gmail.com>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Because of some hardware limitation, AMD I2C controller can't
trigger pending interrupt if interrupt status has been changed
after clearing interrupt status bits. Then, I2C will lost
interrupt and IO timeout.
According to hardware design, this patch implements a workaround
to disable i2c controller interrupt and re-enable i2c interrupt
before exiting ISR.
To reduce the performance impacts on other vendors, use unlikely
function to check flag in ISR.
Signed-off-by: Xiangliang Yu <Xiangliang.Yu@amd.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
There is some code duplication in i2c-designware-platdrv and
i2c-designware-pcidrv probe functions. What is even worse that duplication
requires i2c_dw_xfer(), i2c_dw_func() and i2c_dw_isr() i2c-designware-core
functions to be exported.
Therefore move common code into new i2c_dw_probe() and make functions above
local to i2c-designware-core.
While merging the code patch does following functional changes:
- I2C Adapter name will be "Synopsys DesignWare I2C adapter". Previously it
was used for platform and ACPI devices but PCI device used
"i2c-designware-pci".
- Using device name for interrupt name. Previous it was platform device name,
ACPI device name or "i2c-designware-pci".
- Error code from devm_request_irq() and i2c_add_numbered_adapter() will be
printed in case of error.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
dw_readl() and dw_writel() are not used outside of i2c-designware-core and
they are not exported so make them static and remove their forward
declaration.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
i2c_dw_is_enabled() became unused by the commit be58eda775
("i2c: designware-pci: Cleanup driver power management") and
i2c_dw_enable() by the commit 3a48d1c08f ("i2c: prevent spurious
interrupt on Designware controllers").
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
There is no need to clear interrupts in i2c_dw_pci_probe() since only place
where interrupts are unmasked is i2c_dw_xfer_init() and there interrupts
are always cleared after commit 2a2d95e9d6 ("i2c: designware: always
clear interrupts before enabling them").
This allows to cleanup the code and replace i2c_dw_clear_int() in
i2c_dw_xfer_init() by direct register read as there are no other callers.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Printing adapter name is irrelevant from this debug print and makes output
needlessly long. Having already device and functions names printed here is
enough for debugging.
While at it remove extra space from "enabled= 0x" and use "%#x" for
printing "0x" prefixed hexadecimal values.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
[wsa: made it a oneliner]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
return type of wait_for_completion_timeout is unsigned long not int, rather
than introducing a new variable the wait_for_completion_timeout is moved
into the if condition as the return value is only used to detect timeout.
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Do SCL timing parameter calculation conditionally depending are custom
parameters provided since calculated values will get instantly overwritten
by provided parameters.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Adds support for acquiring and releasing a hardware bus lock in the i2c
designware core transfer function. This is needed for i2c bus controllers
that are shared with but not controlled by the kernel.
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
readl/writel is too expensive especially on Cortex A9 w/ outer L2 cache.
This introduces i2c read/write delays on Marvell BG2/BG2Q SoCs when there
are heavy L2 cache maintenance operations at the same time.
The driver does not perform DMA, so it's safe to use the relaxed version.
From another side, the relaxed io accessor macros are available on all
architectures now, so we can use the relaxed versions instead.
Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If the Designware core is configured with IC_EMPTYFIFO_HOLD_MASTER_EN
set to zero, allowing the TX FIFO to become empty causes a STOP
condition to be generated on the I2C bus. If the transmit FIFO
threshold is set too high, an erroneous STOP condition can be
generated on long transfers - particularly where the interrupt
latency is extended.
Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com>
Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
There have been "i2c_designware 80860F41:00: controller timed out" errors
on a number of Baytrail platforms. The issue is caused by incorrect value in
Interrupt Mask Register (DW_IC_INTR_MASK) when i2c core is being enabled.
This causes call to __i2c_dw_enable() to immediately start the transfer which
leads to timeout. There are 3 failure modes observed:
1. Failure in S0 to S3 resume path
The default value after reset for DW_IC_INTR_MASK is 0x8ff. When we start
the first transaction after resuming from system sleep, TX_EMPTY interrupt
is already unmasked because of the hardware default.
2. Failure in normal operational path
This failure happens rarely and is hard to reproduce. Debug trace showed that
DW_IC_INTR_MASK had value of 0x254 when failure occurred, which meant
TX_EMPTY was unmasked.
3. Failure in S3 to S0 suspend path
This failure also happens rarely and is hard to reproduce. Adding debug trace
that read DW_IC_INTR_MASK made this failure not reproducible. But from ISR
call trace we could conclude TX_EMPTY was unmasked when problem occurred.
The patch masks all interrupts before the controller is enabled to resolve the
faulty DW_IC_INTR_MASK conditions.
Signed-off-by: Wenkai Du <wenkai.du@intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[wsa: improved the comment and removed typo in commit msg]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
This patch allows to set independantly SCL and SDA falling times.
The tLOW period is computed by taking into account the SCL falling time.
The tHIGH period is computed by taking into account the SDA falling time.
For instance in case the margin on tLOW is considered too small, it can
be increased by increasing the SCL falling time which is by default set
at 300ns.
The same applies for tHIGH period with the help of SDA falling time.
Signed-off-by: Romain Baeriswyl <romainba@abilis.com>
Reviewed-by: Christian Ruppert <christian.ruppert@abilis.com>
Acked-by: Shinya Kuribayashi <skuribay@pobox.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Since 93abe8e4 (clk: add non CONFIG_HAVE_CLK routines) code using clk.h
like this platform driver need not depend on HAVE_CLK. Also, remove a
redundant clk.h include from core driver.
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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>
According to Designware I2C spec, if I2C_DYNAMIC_TAR_UPDATE is set to 1,
the 10-bit addressing mode is controlled by IC_10BITADDR_MASTER bit of
IC_TAR register instead of IC_CON register. The IC_10BITADDR_MASTER
in IC_CON register becomes read-only copy. Since I2C_DYNAMIC_TAR_UPDATE
value can't be detected from hardware register, so we will always set the
IC_10BITADDR_MASTER bit in both IC_CON and IC_TAR register whenever 10-bit
addresing mode is requested by user application.
Signed-off-by: Chew, Chiau Ee <chiau.ee.chew@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The DesignWare I2C controller has high count (HCNT) and low count (LCNT)
registers for each of the I2C speed modes (standard and fast). These
registers are programmed based on the input clock speed in the driver.
The current code calculates these values based on the input clock speed and
tries hard to meet the I2C bus timing requirements. This could result
non-optimal values with regarding to the bus speed. For example on Intel
BayTrail we get bus speed of 315.41kHz which is ~20% slower than we would
expect (400kHz) in fast mode (even though the timing requirements are met).
This patch makes it possible for the platform code to pass more optimal
HCNT/LCNT values to the core driver if they are known beforehand. If these
are not set we use the calculated and more conservative values.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Shinya Kuribayashi <skuribay@pobox.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If both IC_EMPTYFIFO_HOLD_MASTER_EN and IC_RESTART_EN are set to 1, the
Designware I2C controller doesn't generate RESTART unless user specifically
requests it by setting RESTART bit in IC_DATA_CMD register.
Since IC_EMPTYFIFO_HOLD_MASTER_EN setting can't be detected from hardware
register, we must always manually set the restart bit between messages.
Signed-off-by: Chew, Chiau Ee <chiau.ee.chew@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This patch makes the SDA hold time configurable through device tree.
Signed-off-by: Christian Ruppert <christian.ruppert@abilis.com>
Signed-off-by: Pierrick Hascoet <pierrick.hascoet@abilis.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com> for arch/arc bits
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The designware block is not always properly disabled in the case of
transfer errors. Interrupts from aborted transfers might be handled
after the data structures for the following transfer are initialised but
before the hardware is set up. This can corrupt the data structures to
the point that the system is stuck in an infinite interrupt loop (where
FIFOs are never emptied because dev->msg_read_idx == dev->msgs_num).
This patch cleanly disables the designware-i2c hardware at the end of
every transfer, be it successful or not.
Signed-off-by: Christian Ruppert <christian.ruppert@abilis.com>
[wsa: extended the comment]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If a process receives signal while it is waiting for I2C transfer to
complete, an error is returned to the caller and the transfer is aborted.
This can cause the driver to fail subsequent transfers. Also according to
commit d295a86eab (i2c: mv64xxx: work around signals causing I2C
transactions to be aborted) I2C drivers aren't supposed to abort
transactions on signals.
To prevent this switch to use wait_for_completion_timeout() instead of
wait_for_completion_interruptible_timeout() in the designware I2C driver.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Christian Ruppert <christian.ruppert@abilis.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If the I2C bus is put to a low power state by an ACPI method it might pull
the SDA line low (as its power is removed). Once the bus is put to full
power state again, the SDA line is pulled back to high. This transition
looks like a STOP condition from the controller point-of-view which sets
STOP detected bit in its status register causing the driver to fail
subsequent transfers.
Fix this by always clearing all interrupts before we start a transfer.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
i2c_dw_xfer_msg() pushes a number of bytes to transmit/receive
to/from the bus into the TX FIFO.
For master-rx transactions, the maximum amount of data that can be
received is calculated depending solely on TX and RX FIFO load.
This is racy - TX FIFO may contain master-rx data yet to be
processed, which will eventually land into the RX FIFO. This
data is not taken into account and the function may request more
data than the controller is actually capable of storing.
This patch ensures the driver takes into account the outstanding
master-rx data in TX FIFO to prevent RX FIFO overrun.
Signed-off-by: Josef Ahmad <josef.ahmad@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
Using autosuspend helps to reduce the resume latency in situations where
another I2C message is going to be started soon. For example with HID over
I2C touch panels we get several messages in a short period of time while
the touch panel is in use.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This is not an atomic context so there is no need to use mdelay() but
instead use usleep_range().
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The correct way to disable or enable the controller is to wait until the
DW_IC_ENABLE_STATUS register bit matches the bit we program into DW_IC_ENABLE
register. This procedure is described in the DesignWare I2C databook.
By doing this we can be sure that the controller is in correct state once
the function returns.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If IC_EMPTYFIFO_HOLD_MASTER_EN is set to one, the DesignWare I2C controller
doesn't generate STOP on the bus when the FIFO is empty. This violates the
rules of Linux I2C stack as it requires that the STOP is issued once the
i2c_transfer() is finished.
However, there is no way to detect this from the hardware registers, so we
must make sure that the STOP bit is always set once the last byte of the
last message is transferred.
This patch is based on the work of Dirk Brandewie.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
The driver can also be built as a module so add MODULE_LICENSE for it. In
addition add MODULE_DESCRIPTION as well.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
