linux-stable.git/drivers/i2c, branch v5.4.68

i2c: i801: Fix resume bug

2020-09-23T10:40:44+00:00

commit 66d402e2e9455cf0213c42b97f22a0493372d7cc upstream.

On suspend the original host configuration gets restored. The
resume routine has to undo this, otherwise the SMBus master
may be left in disabled state or in i2c mode.

[JD: Rebased on v5.8, moved the write into i801_setup_hstcfg.]

Signed-off-by: Volker Rümelin 
Signed-off-by: Jean Delvare 
Signed-off-by: Wolfram Sang 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

i2c: mxs: use MXS_DMA_CTRL_WAIT4END instead of DMA_CTRL_ACK

2020-09-23T10:40:43+00:00

[ Upstream commit 6eb158ec0a45dbfd98bc6971c461b7d4d5bf61b3 ]

The driver-specific usage of the DMA_CTRL_ACK flag was replaced with a
custom flag in commit ceeeb99cd821 ("dmaengine: mxs: rename custom flag"),
but i2c-mxs was not updated to use the new flag, completely breaking I2C
transactions using DMA.

Fixes: ceeeb99cd821 ("dmaengine: mxs: rename custom flag")
Signed-off-by: Matthias Schiffer 
Reviewed-by: Fabio Estevam 
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin

i2c: algo: pca: Reapply i2c bus settings after reset

2020-09-23T10:40:38+00:00

[ Upstream commit 0a355aeb24081e4538d4d424cd189f16c0bbd983 ]

If something goes wrong (such as the SCL being stuck low) then we need
to reset the PCA chip. The issue with this is that on reset we lose all
config settings and the chip ends up in a disabled state which results
in a lock up/high CPU usage. We need to re-apply any configuration that
had previously been set and re-enable the chip.

Signed-off-by: Evan Nimmo 
Reviewed-by: Chris Packham 
Reviewed-by: Andy Shevchenko 
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin

i2c: rcar: in slave mode, clear NACK earlier

2020-09-03T09:26:55+00:00

[ Upstream commit 914a7b3563b8fb92f976619bbd0fa3a4a708baae ]

Currently, a NACK in slave mode is set/cleared when SCL is held low by
the IP core right before the bit is about to be pushed out. This is too
late for clearing and then a NACK from the previous byte is still used
for the current one. Now, let's clear the NACK right after we detected
the STOP condition following the NACK.

Fixes: de20d1857dd6 ("i2c: rcar: add slave support")
Signed-off-by: Wolfram Sang 
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin

i2c: core: Don't fail PRP0001 enumeration when no ID table exist

2020-09-03T09:26:55+00:00

[ Upstream commit e3cb82c6d6f6c27ab754e13ae29bdd6b949982e2 ]

When commit c64ffff7a9d1 ("i2c: core: Allow empty id_table in ACPI case
as well") fixed the enumeration of I²C devices on ACPI enabled platforms
when driver has no ID table, it missed the PRP0001 support.

i2c_device_match() and i2c_acpi_match_device() differently match
driver against given device. Use acpi_driver_match_device(), that is used
in the former, in i2c_device_probe() and don't fail PRP0001 enumeration
when no ID table exist.

Fixes: c64ffff7a9d1 ("i2c: core: Allow empty id_table in ACPI case as well")
BugLink: https://stackoverflow.com/q/63519678/2511795
Signed-off-by: Andy Shevchenko 
Reviewed-by: Mika Westerberg 
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin

i2c: iproc: fix race between client unreg and isr

2020-08-21T11:05:38+00:00

[ Upstream commit b1eef236f50ba6afea680da039ef3a2ca9c43d11 ]

When i2c client unregisters, synchronize irq before setting
iproc_i2c->slave to NULL.

(1) disable_irq()
(2) Mask event enable bits in control reg
(3) Erase slave address (avoid further writes to rx fifo)
(4) Flush tx and rx FIFOs
(5) Clear pending event (interrupt) bits in status reg
(6) enable_irq()
(7) Set client pointer to NULL

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000318

[  371.020421] pc : bcm_iproc_i2c_isr+0x530/0x11f0
[  371.025098] lr : __handle_irq_event_percpu+0x6c/0x170
[  371.030309] sp : ffff800010003e40
[  371.033727] x29: ffff800010003e40 x28: 0000000000000060
[  371.039206] x27: ffff800010ca9de0 x26: ffff800010f895df
[  371.044686] x25: ffff800010f18888 x24: ffff0008f7ff3600
[  371.050165] x23: 0000000000000003 x22: 0000000001600000
[  371.055645] x21: ffff800010f18888 x20: 0000000001600000
[  371.061124] x19: ffff0008f726f080 x18: 0000000000000000
[  371.066603] x17: 0000000000000000 x16: 0000000000000000
[  371.072082] x15: 0000000000000000 x14: 0000000000000000
[  371.077561] x13: 0000000000000000 x12: 0000000000000001
[  371.083040] x11: 0000000000000000 x10: 0000000000000040
[  371.088519] x9 : ffff800010f317c8 x8 : ffff800010f317c0
[  371.093999] x7 : ffff0008f805b3b0 x6 : 0000000000000000
[  371.099478] x5 : ffff0008f7ff36a4 x4 : ffff8008ee43d000
[  371.104957] x3 : 0000000000000000 x2 : ffff8000107d64c0
[  371.110436] x1 : 00000000c00000af x0 : 0000000000000000

[  371.115916] Call trace:
[  371.118439]  bcm_iproc_i2c_isr+0x530/0x11f0
[  371.122754]  __handle_irq_event_percpu+0x6c/0x170
[  371.127606]  handle_irq_event_percpu+0x34/0x88
[  371.132189]  handle_irq_event+0x40/0x120
[  371.136234]  handle_fasteoi_irq+0xcc/0x1a0
[  371.140459]  generic_handle_irq+0x24/0x38
[  371.144594]  __handle_domain_irq+0x60/0xb8
[  371.148820]  gic_handle_irq+0xc0/0x158
[  371.152687]  el1_irq+0xb8/0x140
[  371.155927]  arch_cpu_idle+0x10/0x18
[  371.159615]  do_idle+0x204/0x290
[  371.162943]  cpu_startup_entry+0x24/0x60
[  371.166990]  rest_init+0xb0/0xbc
[  371.170322]  arch_call_rest_init+0xc/0x14
[  371.174458]  start_kernel+0x404/0x430

Fixes: c245d94ed106 ("i2c: iproc: Add multi byte read-write support for slave mode")

Signed-off-by: Dhananjay Phadke 
Reviewed-by: Florian Fainelli 
Acked-by: Ray Jui 
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin

i2c: rcar: avoid race when unregistering slave

2020-08-21T11:05:34+00:00

[ Upstream commit c7c9e914f9a0478fba4dc6f227cfd69cf84a4063 ]

Due to the lockless design of the driver, it is theoretically possible
to access a NULL pointer, if a slave interrupt was running while we were
unregistering the slave. To make this rock solid, disable the interrupt
for a short time while we are clearing the interrupt_enable register.
This patch is purely based on code inspection. The OOPS is super-hard to
trigger because clearing SAR (the address) makes interrupts even more
unlikely to happen as well. While here, reinit SCR to SDBS because this
bit should always be set according to documentation. There is no effect,
though, because the interface is disabled.

Fixes: 7b814d852af6 ("i2c: rcar: avoid race when unregistering slave client")
Signed-off-by: Wolfram Sang 
Reviewed-by: Niklas Söderlund 
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin

i2c: rcar: slave: only send STOP event when we have been addressed

2020-08-21T11:05:34+00:00

[ Upstream commit 314139f9f0abdba61ed9a8463bbcb0bf900ac5a2 ]

When the SSR interrupt is activated, it will detect every STOP condition
on the bus, not only the ones after we have been addressed. So, enable
this interrupt only after we have been addressed, and disable it
otherwise.

Fixes: de20d1857dd6 ("i2c: rcar: add slave support")
Signed-off-by: Wolfram Sang 
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin

i2c: slave: add sanity check when unregistering

2020-08-11T13:33:37+00:00

[ Upstream commit 8808981baf96e1b3dea1f08461e4d958aa0dbde1 ]

Signed-off-by: Wolfram Sang 
Reviewed-by: Alain Volmat 
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin

i2c: slave: improve sanity check when registering

2020-08-11T13:33:37+00:00

[ Upstream commit 1b1be3bf27b62f5abcf85c6f3214bdb9c7526685 ]

Add check for ERR_PTR and simplify code while here.

Signed-off-by: Wolfram Sang 
Reviewed-by: Alain Volmat 
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin