No functional changes.
Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Arbitration Lost is an expected situation in a multimaster
environment. I2C controller (IP) correctly detect and report AL.
The only one visible reason for resetting IP in the AL case is
to avoid advisory 1.94 (omap3) and errata i595 (omap4): "I2C:
After an Arbitration is Lost the Module Incorrectly Starts
the Next Transfer".
Errata workaround states: "The MST and STT bits inside I2C_CON
should be set to 1 at the same moment (avoid setting the MST bit
to 1 while STT = 0)." The driver never set MST and STT bits
separately and doesn't create condition for errata. So the reset
is not necessary.
Also corrected return value for AL to -EAGAIN.
Tested on Beagleboard XM C.
Tested on BBB and AM437x Starter Kit by Felipe Balbi.
Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Tested-by: Felipe Balbi <balbi@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
In a multimaster environment, after IP software reset, BB-bit value doesn't
correspond to the current bus state. It may happen what BB-bit will be 0,
while the bus is busy due to another I2C master activity.
Any transfer started when BB=0 and bus is busy wouldn't be completed by IP
and results in controller timeout. More over, in some cases IP could
interrupt another master's transfer and corrupt data on wire.
The commit implement method allowing to prevent IP from entering into
"controller timeout" state and from "data corruption" state.
The one drawback is the need to wait for 10ms before the first transfer.
Tested on Beagleboard XM C.
Tested on BBB and AM437x Starter Kit by Felipe Balbi.
Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Tested-by: Felipe Balbi <balbi@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Delete STAT_AD0 mask as unrelated to current IP (omap1?).
Delete DEBUG conditional around SYSTEST masks group.
Add SYSTEST functional mode masks for SCL and SDA.
Add STAT_BF mask.
Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Tested-by: Felipe Balbi <balbi@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The i2c input clock can change dynamically, e.g. on the RK3066 where
pclk_i2c0 and pclk_i2c1 are connected to the armclk, which changes
rate on cpu frequency scaling.
Until now, we incorrectly called clk_get_rate() while holding the
i2c->lock in rk3x_i2c_xfer() to adapt to clock rate changes.
Thanks to Huang Tao for reporting this issue.
Do it properly now using the clk notifier framework. The callback
logic was taken from i2c-cadence.c.
Also rename all misleading "i2c_rate" variables to "clk_rate", as they
describe the *input* clk rate.
Signed-off-by: Max Schwarz <max.schwarz@online.de>
Tested-by: Doug Anderson <dianders@chromium.org> on RK3288
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Since at91sam9g45 is now DT-only, all DMA capable users of this driver
are using the DT case, and the legacy support can be removed.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
It should be the DMA device, not the platform device.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The SCB is present on IMG SoCs other than the META-based TZ1090,
such as the MIPS-based Pistachio SoC. Relax the Kconfig dependency
so that it can be built on any MIPS or META machine.
Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Acked-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This is a driver for the I2C controller found in Amlogic Meson SoCs.
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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>
Add support for the IMG I2C Serial Control Bus (SCB) found on the
Pistachio and TZ1090 SoCs.
Reviewed-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
[Ezequiel: code cleaning and rebasing]
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The driver tried to access device registers with the (little-endian)
iowrite/ioread functions. While this worked on little-endian machines
(e.g. Microblaze with AXI bus), it made the driver unusable on
big-endian machines (e.g. PPC405 with PLB).
During the probe function, the driver tried to write a 32-bit reset mask
into the reset register. This caused an error interrupt on big-endian
systems, because the device detected an invalid (byte-swapped) reset
mask. The result was an Oops.
The patch implements an endianness detection similar to the one used in
other Xilinx drivers like drivers/spi/spi-xilinx.c. It was tested on a
PPC405/PLB system.
Signed-off-by: Thomas Gessler <Thomas.Gessler@exp2.physik.uni-giessen.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
No user needs magic hex values, makes this debug output. Add DMA info.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Make it possible to transfer i2c message buffers via DMA.
Start/Stop/Sending_Slave_Address is still handled using the old state
machine, it is sending the actual data that is done via DMA. This is
least intrusive and allows us to work with the message buffers directly
instead of preparing a custom buffer which involves copying the data
around.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
[wsa: fixed an uninitialized var problem]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Improves readability and reduces chances of duplicates.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Amend the at91 i2c pin controller to set the state of the pins to:
- "default" on resume.
- "sleep" on suspend().
This should make it possible to optimize energy usage for the pins
both for the suspend/resume cycle
Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This patch enforces correct I2C error returned codes from Freescale's
MPC i2c bus driver, allowing for proper user-space/kernel error
handling.
Signed-off-by: Danielle Costantino <danielle.costantino@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Don't log the host status register value in i801_isr(), it has very
little value and fills up the log when debugging is enabled.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
There is a control bit in the PCI configuration space which disables
interrupts. If this bit is set, the driver should not try to make use
of interrupts, it won't receive any.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The i2c-i801 driver can work without interrupts, so there is no reason
to make a request_irq failure fatal. Instead we can simply fallback
to polling.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Some systems have been reported to have trouble with interrupts. Use
wait_event_timeout() instead of wait_event() so we don't get stuck in
that case, and log the problem.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
As show in I2C specification:
- Standard-mode: the minimum HIGH period of the scl clock is 4.0us
the minimum LOW period of the scl clock is 4.7us
- Fast-mode: the minimum HIGH period of the scl clock is 0.6us
the minimum LOW period of the scl clock is 1.3us
I have measured i2c SCL waveforms in fast-mode by oscilloscope
on rk3288-pinky board. the LOW period of the scl clock is 1.3us.
It is so critical that we must adjust LOW division to increase
the LOW period of the scl clock.
Thanks Doug for the suggestion about division formulas.
Signed-off-by: Addy Ke <addy.ke@rock-chips.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Max Schwarz <max.schwarz@online.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
When a signal is caught while the i2c-davinci bus driver is
transferring, the driver just "abandons" the transfer and leaves the
controller to fend for itself. The next I2C transaction will find the
controller in an undefined state and often results in a stream of
"initiating i2c bus recovery" messages until the controller arrives in a
defined state. This behaviour also sends out "half" or possibly even
mixed messages to I2C client devices which may put them in an undesired
state as well. So, let's get simply uninterruptible.
Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Drivers should put the device into low power states proactively whenever the
device is not in use. Thus implement support for runtime PM and use the
autosuspend feature to make sure that we can still perform well in case we see
lots of i2c traffic within short period of time.
Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add support for r8a73a4 (R-Mobile APE6) and sh73a0 (SH-Mobile AG5).
On these SoCs, the operating clock runs faster that on previous SoCs,
and the internal SCL clock counter gets incremented every 2 clocks of
the operating clock, just like on R-Car Gen2.
Cfr. the "/2" in the calculation of ICCL/ICCH in section "I2C Bus
Interface (IIC)", subsection "Transfer Rate" of the datasheets.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
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>
iowait is for blkio [1]. I2C shouldn't use it.
[1] https://lkml.org/lkml/2014/11/3/317
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: stable@kernel.org
Pull i2c updates from Wolfram Sang:
"Highlights from the I2C subsystem for 3.18:
- new drivers for Axxia AM55xx, and Hisilicon hix5hd2 SoC.
- designware driver gained AMD support, exynos gained exynos7 support
The rest is usual driver stuff. Hopefully no lowlights this time"
* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: i801: Add Device IDs for Intel Sunrise Point PCH
i2c: hix5hd2: add i2c controller driver
i2c-imx: Disable the clock on probe failure
i2c: designware: Add support for AMD I2C controller
i2c: designware: Rework probe() to get clock a bit later
i2c: designware: Default to fast mode in case of ACPI
i2c: axxia: Add I2C driver for AXM55xx
i2c: exynos: add support for HSI2C module on Exynos7
i2c: mxs: detect No Slave Ack on SELECT in PIO mode
i2c: cros_ec: Remove EC_I2C_FLAG_10BIT
i2c: cros-ec-tunnel: Add of match table
i2c: rcar: remove sign-compare flaw
i2c: ismt: Use minimum descriptor size
i2c: imx: Add arbitration lost check
i2c: rk3x: Remove unlikely() annotations
i2c: rcar: check for no IRQ in rcar_i2c_irq()
i2c: rcar: make rcar_i2c_prepare_msg() *void*
i2c: rcar: simplify check for last message
i2c: designware: add support of platform data to set I2C mode
i2c: designware: add support of I2C standard mode
This patch adds the I2C/SMBus Device IDs for the Intel Sunrise Point PCH.
Signed-off-by: James Ralston <james.d.ralston@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
I2C drivers for hix5hd2 soc series, including following chipset
Hi3716CV200, Hi3719CV100, Hi3718CV100, Hi3719MV100, Hi3718MV100.
Signed-off-by: Wei Yan <sledge.yanwei@huawei.com>
Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
[wsa: folded dt docs into this patch]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
- DT clean-ups in da9055-core, max14577, rn5t618, arizona, hi6421, stmpe, twl4030
- Export symbols for use in modules in max14577
- Plenty of static code analysis/Coccinelle fixes throughout the SS
- Regmap clean-ups in arizona, wm5102, wm5110, da9052, tps65217, rk808
- Remove unused/duplicate code in da9052, 88pm860x, ti_ssp, lpc_sch, arizona
- Bug fixes in ti_am335x_tscadc, da9052, ti_am335x_tscadc, rtsx_pcr
- IRQ fixups in arizona, stmpe, max14577
- Regulator related changes in axp20x
- Pass DMA coherency information from parent => child in MFD core
- Rename DT document files for consistency
- Add ACPI support to the MFD core
- Add Andreas Werner to MAINTAINERS for MEN F21BMC
New drivers/supported devices:
- New driver for MEN 14F021P00 Board Management Controller
- New driver for Ricoh RN5T618 PMIC
- New driver for Rockchip RK808
- New driver for HiSilicon Hi6421 PMIC
- New driver for Qualcomm SPMI PMICs
- Add support for Intel Braswell in lpc_ich
- Add support for Intel 9 Series PCH in lpc_ich
- Add support for Intel Quark ILB in lpc_sch
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Merge tag 'mfd-for-linus-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd
Pull MFD updates from Lee Jones:
"Changes to existing drivers:
- DT clean-ups in da9055-core, max14577, rn5t618, arizona, hi6421, stmpe, twl4030
- Export symbols for use in modules in max14577
- Plenty of static code analysis/Coccinelle fixes throughout the SS
- Regmap clean-ups in arizona, wm5102, wm5110, da9052, tps65217, rk808
- Remove unused/duplicate code in da9052, 88pm860x, ti_ssp, lpc_sch, arizona
- Bug fixes in ti_am335x_tscadc, da9052, ti_am335x_tscadc, rtsx_pcr
- IRQ fixups in arizona, stmpe, max14577
- Regulator related changes in axp20x
- Pass DMA coherency information from parent => child in MFD core
- Rename DT document files for consistency
- Add ACPI support to the MFD core
- Add Andreas Werner to MAINTAINERS for MEN F21BMC
New drivers/supported devices:
- New driver for MEN 14F021P00 Board Management Controller
- New driver for Ricoh RN5T618 PMIC
- New driver for Rockchip RK808
- New driver for HiSilicon Hi6421 PMIC
- New driver for Qualcomm SPMI PMICs
- Add support for Intel Braswell in lpc_ich
- Add support for Intel 9 Series PCH in lpc_ich
- Add support for Intel Quark ILB in lpc_sch"
[ Delayed to after the poweer/reset pull due to Kconfig problems with
recursive Kconfig select/depends-on chains. - Linus ]
* tag 'mfd-for-linus-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd: (79 commits)
mfd: cros_ec: wait for completion of commands that return IN_PROGRESS
i2c: i2c-cros-ec-tunnel: Set retries to 3
mfd: cros_ec: move locking into cros_ec_cmd_xfer
mfd: cros_ec: stop calling ->cmd_xfer() directly
mfd: cros_ec: Delay for 50ms when we see EC_CMD_REBOOT_EC
MAINTAINERS: Adds Andreas Werner to maintainers list for MEN F21BMC
mfd: arizona: Correct mask to allow setting micbias external cap
mfd: Add ACPI support
Revert "mfd: wm5102: Manually apply register patch"
mfd: ti_am335x_tscadc: Update logic in CTRL register for 5-wire TS
mfd: dt-bindings: atmel-gpbr: Rename doc file to conform to naming convention
mfd: dt-bindings: qcom-pm8xxx: Rename doc file to conform to naming convention
mfd: Inherit coherent_dma_mask from parent device
mfd: Document DT bindings for Qualcomm SPMI PMICs
mfd: Add support for Qualcomm SPMI PMICs
mfd: dt-bindings: pm8xxx: Add new compatible string
mfd: axp209x: Drop the parent supplies field
mfd: twl4030-power: Use 'ti,system-power-controller' as alternative way to support system power off
mfd: dt-bindings: twl4030-power: Use the standard property to mark power control
mfd: syscon: Add Atmel GPBR DT bindings documention
...
Since the i2c bus can get wedged on the EC sometimes, set the number of retries
to 3. Since we un-wedge the bus immediately after the wedge happens, this is the
correct fix since only one transfer will fail.
Signed-off-by: Derek Basehore <dbasehore@chromium.org>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Instead of having users of the ChromeOS EC call the interface-specific
cmd_xfer() callback directly, introduce a central cros_ec_cmd_xfer()
to use instead. This will allow us to put all the locking and retry
logic in one place instead of duplicating it across the different
drivers.
Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
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>
Add support for AMD version of the DW I2C host controller. The device is
enumerated from ACPI namespace with ACPI ID AMD0010. Because the core
driver needs an input source clock, and this is not an Intel LPSS device
where clocks are provided through drivers/acpi/acpi_lpss.c, we register the
clock ourselves if the clock rate is given in ->driver_data
Signed-off-by: Carl Peng <carlpeng008@gmail.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
In order to be able to create missing clock for AMD (and in future possibly
others) we move getting clock for the device a bit later. Also make ACPI/DT
configuration in the same place depending on from where the device was
enumerated from.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
There is no way in ACPI to tell in which speed the host controller is
supposed to run, so we default to fast mode (400KHz). Since this has been
the default all the time there should be no functional changes with this
change.
This is the first step required to refactor the driver probe so that we can
supply source clock from ACPI part of the driver to the core.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add I2C bus driver for the controller found in the LSI Axxia family SoCs. The
driver implements 10-bit addressing and SMBus transfer modes via emulation
(including SMBus block data read).
Signed-off-by: Anders Berg <anders.berg@avagotech.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The HSI2C module on Exynos7 differs in the transfer status
bits. Transfer status bits were moved to INT_ENABLE and
INT_STATUS registers
This patch adds support for the HSI2C module on Exynos7.
1. Implementes a "hw" field in the variant struct to distinguish
the hardware.
2. Updates the dt-new compatible in dt-binding documenation
Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@samsung.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>
The runtime pm calls need to be done before populating the children via the
i2c_add_adapter call. If this is not done, a child can run into issues trying
to do i2c read/writes due to the pm_runtime_sync failing.
Signed-off-by: Andy Gross <agross@codeaurora.org>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Acked-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
i2cdetect -q was broken (everything was a false positive, and no transfers were
actually being sent over i2c). The way it works is by sending a 0 length write
request and checking for NACK. This patch fixes the 0 length writes and actually
sends them.
Reported-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Alexandru M Stan <amstan@chromium.org>
Tested-by: Doug Anderson <dianders@chromium.org>
Tested-by: Max Schwarz <max.schwarz@online.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
Alexander Kochetkov