linux-stable.git/drivers/i2c, branch v5.0.9

i2c: of: Try to find an I2C adapter matching the parent

2019-04-05T20:34:43+00:00

[ Upstream commit e814e688413aabd7b0d75e2a8ed1caa472951dec ]

If an I2C adapter doesn't match the provided device tree node, also try
matching the parent's device tree node. This allows finding an adapter
based on the device node of the parent device that was used to register
it.

This fixes a regression on Tegra124-based Chromebooks (Nyan) where the
eDP controller registers an I2C adapter that is used to read to EDID.
After commit 993a815dcbb2 ("dt-bindings: panel: Add missing .txt
suffix") this stopped working because the I2C adapter could no longer
be found. The approach in this patch fixes the regression without
introducing the issues that the above commit solved.

Fixes: 17ab7806de0c ("drm: don't link DP aux i2c adapter to the hardware device node")
Signed-off-by: Thierry Reding 
Tested-by: Tristan Bastian 
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin

i2c: designware: Do not allow i2c_dw_xfer() calls while suspended

2019-04-05T20:34:32+00:00

[ Upstream commit 2751541555382dfa7661bcfaac3ee0fac49f505d ]

On most Intel Bay- and Cherry-Trail systems the PMIC is connected over I2C
and the PMIC is accessed through various means by the _PS0 and _PS3 ACPI
methods (power on / off methods) of various devices.

This leads to suspend/resume ordering problems where a device may be
resumed and get its _PS0 method executed before the I2C controller is
resumed. On Cherry Trail this leads to errors like these:

     i2c_designware 808622C1:06: controller timed out
     ACPI Error: AE_ERROR, Returned by Handler for [UserDefinedRegion]
     ACPI Error: Method parse/execution failed \_SB.P18W._ON, AE_ERROR
     video LNXVIDEO:00: Failed to change power state to D0

But on Bay Trail this caused I2C reads to seem to succeed, but they end
up returning wrong data, which ends up getting written back by the typical
read-modify-write cycle done to turn on various power-resources.

Debugging the problems caused by this silent data corruption is quite
nasty. This commit adds a check which disallows i2c_dw_xfer() calls to
happen until the controller's resume method has completed.

Which turns the silent data corruption into getting these errors in
dmesg instead:

    i2c_designware 80860F41:04: Error i2c_dw_xfer call while suspended
    ACPI Error: AE_ERROR, Returned by Handler for [UserDefinedRegion]
    ACPI Error: Method parse/execution failed \_SB.PCI0.GFX0._PS0, AE_ERROR

Which is much better.

Note the above errors are an example of issues which this patch will
help to debug, the actual fix requires fixing the suspend order and
this has been fixed by a different commit.

Note the setting / clearing of the suspended flag in the suspend / resume
methods is NOT protected by i2c_lock_bus(). This is intentional as these
methods get called from i2c_dw_xfer() (through pm_runtime_get/put) a nd
i2c_dw_xfer() is called with the i2c_bus_lock held, so otherwise we would
deadlock. This means that there is a theoretical race between a non runtime
suspend and the suspended check in i2c_dw_xfer(), this is not a problem
since normally we should not hit the race and this check is primarily a
debugging tool so hitting the check if there are suspend/resume ordering
problems does not need to be 100% reliable.

Signed-off-by: Hans de Goede 
Reviewed-by: Andy Shevchenko 
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin

i2c: Allow recovery of the initial IRQ by an I2C client device.

2019-04-05T20:34:31+00:00

[ Upstream commit 93b6604c5a669d84e45fe5129294875bf82eb1ff ]

A previous change allowed I2C client devices to discover new IRQs upon
reprobe by clearing the IRQ in i2c_device_remove. However, if an IRQ was
assigned in i2c_new_device, that information is lost.

For example, the touchscreen and trackpad devices on a Dell Inspiron laptop
are I2C devices whose IRQs are defined by ACPI extended IRQ types. The
client device structures are initialized during an ACPI walk. After
removing the i2c_hid device, modprobe fails.

This change caches the initial IRQ value in i2c_new_device and then resets
the client device IRQ to the initial value in i2c_device_remove.

Fixes: 6f108dd70d30 ("i2c: Clear client->irq in i2c_device_remove")
Signed-off-by: Jim Broadus 
Reviewed-by: Benjamin Tissoires 
Reviewed-by: Charles Keepax 
[wsa: this is an easy to backport fix for the regression. We will
refactor the code to handle irq assignments better in general.]
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin

i2c: tegra: update maximum transfer size

2019-03-23T19:11:25+00:00

commit b03ff2a23359d0dd6f0a1516c6a9e9c4760ed230 upstream.

Tegra194 supports maximum 64K bytes per packet including 12 bytes of
packet header irrespective of PIO or DMA mode transfer.

This patch updates Tegra194 max write length to account for packet
header size for transfers.

Cc: stable@vger.kernel.org # 4.20+

Reviewed-by: Dmitry Osipenko 
Signed-off-by: Sowjanya Komatineni 
Signed-off-by: Wolfram Sang 
Signed-off-by: Greg Kroah-Hartman

i2c: tegra: fix maximum transfer size

2019-03-23T19:11:25+00:00

commit f4e3f4ae1d9c9330de355f432b69952e8cef650c upstream.

Tegra186 and prior supports maximum 4K bytes per packet transfer
including 12 bytes of packet header.

This patch fixes max write length limit to account packet header
size for transfers.

Cc: stable@vger.kernel.org # 4.4+

Reviewed-by: Dmitry Osipenko 
Signed-off-by: Sowjanya Komatineni 
Signed-off-by: Wolfram Sang 
Signed-off-by: Greg Kroah-Hartman

i2c: bcm2835: Clear current buffer pointers and counts after a transfer

2019-02-15T08:45:05+00:00

The driver's interrupt handler checks whether a message is currently
being handled with the curr_msg pointer. When it is NULL, the interrupt
is considered to be unexpected. Similarly, the i2c_start_transfer
routine checks for the remaining number of messages to handle in
num_msgs.

However, these values are never cleared and always keep the message and
number relevant to the latest transfer (which might be done already and
the underlying message memory might have been freed).

When an unexpected interrupt hits with the DONE bit set, the isr will
then try to access the flags field of the curr_msg structure, leading
to a fatal page fault.

The msg_buf and msg_buf_remaining fields are also never cleared at the
end of the transfer, which can lead to similar pitfalls.

Fix these issues by introducing a cleanup function and always calling
it after a transfer is finished.

Fixes: e2474541032d ("i2c: bcm2835: Fix hang for writing messages larger than 16 bytes")
Signed-off-by: Paul Kocialkowski 
Acked-by: Stefan Wahren 
Signed-off-by: Wolfram Sang

i2c: cadence: Fix the hold bit setting

2019-02-15T08:42:17+00:00

In case the hold bit is not needed we are carrying the old values.
Fix the same by resetting the bit when not needed.

Fixes the sporadic i2c bus lockups on National Instruments
Zynq-based devices.

Fixes: df8eb5691c48 ("i2c: Add driver for Cadence I2C controller")
Reported-by: Kyle Roeschley 
Acked-by: Michal Simek 
Signed-off-by: Shubhrajyoti Datta 
Tested-by: Kyle Roeschley 
Signed-off-by: Wolfram Sang

i2c: omap: Use noirq system sleep pm ops to idle device for suspend

2019-02-05T12:13:20+00:00

We currently get the following error with pixcir_ts driver during a
suspend resume cycle:

omap_i2c 4802a000.i2c: controller timed out
pixcir_ts 1-005c: pixcir_int_enable: can't read reg 0x34 : -110
pixcir_ts 1-005c: Failed to disable interrupt generation: -110
pixcir_ts 1-005c: Failed to stop
dpm_run_callback(): pixcir_i2c_ts_resume+0x0/0x98
[pixcir_i2c_ts] returns -110
PM: Device 1-005c failed to resume: error -110

And at least am437x based devices with pixcir_ts will fail to resume
to a touchscreen that is configured as the wakeup-source in device
tree for these devices.

This is because pixcir_ts tries to reconfigure it's registers for
noirq suspend which fails. This also leaves i2c-omap in enabled state
for suspend.

Let's fix the pixcir_ts issue and make sure i2c-omap is suspended by
adding SET_NOIRQ_SYSTEM_SLEEP_PM_OPS.

Let's also get rid of some ifdefs while at it and replace them with
__maybe_unused as SET_RUNTIME_PM_OPS and SET_NOIRQ_SYSTEM_SLEEP_PM_OPS
already deal with the various PM Kconfig options.

Reported-by: Keerthy 
Signed-off-by: Tony Lindgren 
Acked-by: Vignesh R 
Signed-off-by: Wolfram Sang

i2c: tegra: Fix Maximum transfer size

2019-01-10T23:15:04+00:00

Tegra194 supports maximum 64K Bytes transfer per packet.
Tegra186 and prior supports maximum 4K Bytes transfer per packet.

This patch fixes this payload difference between Tegra194 and prior
Tegra chipsets using separate i2c_adapter_quirks.

Signed-off-by: Sowjanya Komatineni 
Acked-by: Thierry Reding 
Signed-off-by: Wolfram Sang

i2c: dev: prevent adapter retries and timeout being set as minus value

2019-01-10T23:14:55+00:00

If adapter->retries is set to a minus value from user space via ioctl,
it will make __i2c_transfer and __i2c_smbus_xfer skip the calling to
adapter->algo->master_xfer and adapter->algo->smbus_xfer that is
registered by the underlying bus drivers, and return value 0 to all the
callers. The bus driver will never be accessed anymore by all users,
besides, the users may still get successful return value without any
error or information log print out.

If adapter->timeout is set to minus value from user space via ioctl,
it will make the retrying loop in __i2c_transfer and __i2c_smbus_xfer
always break after the the first try, due to the time_after always
returns true.

Signed-off-by: Yi Zeng 
[wsa: minor grammar updates to commit message]
Signed-off-by: Wolfram Sang 
Cc: stable@kernel.org