linux-toradex.git/drivers/i2c, branch v4.4.129

i2c: i2c-scmi: add a MS HID

2018-03-24T09:58:41+00:00

[ Upstream commit e058e7a4bc89104540a8a303682248614b5df6f1 ]

Description of the problem:
 - i2c-scmi driver contains only two identifiers "SMBUS01" and "SMBUSIBM";
 - the fist HID (SMBUS01) is clearly defined in "SMBus Control Method
   Interface Specification, version 1.0": "Each device must specify
   'SMBUS01' as its _HID and use a unique _UID value";
 - unfortunately, BIOS vendors (like AMI) seem to ignore this requirement
   and implement "SMB0001" HID instead of "SMBUS01";
 - I speculate that they do this because only "SMB0001" is hard coded in
   Windows SMBus driver produced by Microsoft.

This leads to following situation:
 - SMBus works out of box in Windows but not in Linux;
 - board vendors are forced to add correct "SMBUS01" HID to BIOS to make
   SMBus work in Linux. Moreover the same board vendors complain that
   tools (3-rd party ASL compiler) do not like the "SMBUS01" identifier
   and produce errors.  So they need to constantly patch the compiler for
   each new version of BIOS.

As it is very unlikely that BIOS vendors implement a correct HID in
future, I would propose to consider whether it is possible to work around
the problem by adding MS HID to the Linux i2c-scmi driver.

v2: move the definition of the new HID to the driver itself.

Signed-off-by: Edgar Cherkasov 
Signed-off-by: Michael Brunner 
Acked-by: Viktor Krasnov 
Reviewed-by: Jean Delvare 
Reviewed-by: Mika Westerberg 
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

i2c: remove __init from i2c_register_board_info()

2018-02-25T10:03:48+00:00

commit 5abe9b26847c65a698f38744a52635b287514294 upstream.

As of next-20160607 with allyesconfig we get this linker failure:

  MODPOST vmlinux.o
WARNING: vmlinux.o(.text+0x21bc0d): Section mismatch in reference from
the function intel_scu_devices_create() to the function
.init.text:i2c_register_board_info()

This is caused by the fact that intel_scu_devices_create() calls
i2c_register_board_info() and intel_scu_devices_create() is not
annotated with __init. This typically involves manual code
inspection and if one is certain this is correct we would
just peg intel_scu_devices_create() with a __ref annotation.

In this case this would be wrong though as the
intel_scu_devices_create() call is exported, and used in
the ipc_probe() on drivers/platform/x86/intel_scu_ipc.c.
The issue is that even though builtin_pci_driver(ipc_driver)
is used this just exposes the probe routine, which can occur
at any point in time if this bus supports hotplug. A race
can happen between kernel_init_freeable() that calls the init
calls (in this case registeres the intel_scu_ipc.c driver, and
later free_initmem(), which would free the i2c_register_board_info().
If a probe happens later in boot i2c_register_board_info() would
not be present and we should get a page fault.

Signed-off-by: Luis R. Rodriguez 
[wsa: made function declaration a one-liner]
Signed-off-by: Wolfram Sang 
Signed-off-by: Greg Kroah-Hartman

i2c: riic: fix restart condition

2017-12-16T09:33:53+00:00

[ Upstream commit 2501c1bb054290679baad0ff7f4f07c714251f4c ]

While modifying the driver to use the STOP interrupt, the completion of the
intermediate transfers need to wake the driver back up in order to initiate
the next transfer (restart condition). Otherwise you get never ending
interrupts and only the first transfer sent.

Fixes: 71ccea095ea1 ("i2c: riic: correctly finish transfers")
Reported-by: Simon Horman 
Signed-off-by: Chris Brandt 
Tested-by: Simon Horman 
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

i2c: riic: correctly finish transfers

2017-11-08T09:06:29+00:00

[ Upstream commit 71ccea095ea1d4efd004dab971be6d599e06fc3f ]

This fixes the condition where the controller has not fully completed its
final transfer and leaves the bus and controller in a undesirable state.

At the end of the last transmitted byte, the existing driver would just
signal for a STOP condition to be transmitted then immediately signal
completion. However, the full STOP procedure might not have fully taken
place by the time the runtime PM shuts off the peripheral clock, leaving
the bus in a suspended state.

Alternatively, the STOP condition on the bus may have completed, but when
the next transaction is requested by the upper layer, not all the
necessary register cleanup was finished from the last transfer which made
the driver return BUS BUSY when it really wasn't.

This patch now makes all transmit and receive transactions wait for the
STOP condition to fully complete before signaling a completed transaction.
With this new method, runtime PM no longer seems to be an issue.

Fixes: 310c18a41450 ("i2c: riic: add driver")
Signed-off-by: Chris Brandt 
Reviewed-by: Wolfram Sang 
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

i2c: ismt: Separate I2C block read from SMBus block read

2017-10-27T08:23:16+00:00

commit c6ebcedbab7ca78984959386012a17b21183e1a3 upstream.

Commit b6c159a9cb69 ("i2c: ismt: Don't duplicate the receive length for
block reads") broke I2C block reads. It aimed to fix normal SMBus block
read, but changed the correct behavior of I2C block read in the process.

According to Documentation/i2c/smbus-protocol, one vital difference
between normal SMBus block read and I2C block read is that there is no
byte count prefixed in the data sent on the wire:

 SMBus Block Read:  i2c_smbus_read_block_data()
 S Addr Wr [A] Comm [A]
            S Addr Rd [A] [Count] A [Data] A [Data] A ... A [Data] NA P

 I2C Block Read:  i2c_smbus_read_i2c_block_data()
 S Addr Wr [A] Comm [A]
            S Addr Rd [A] [Data] A [Data] A ... A [Data] NA P

Therefore the two transaction types need to be processed differently in
the driver by copying of the dma_buffer as done previously for the
I2C_SMBUS_I2C_BLOCK_DATA case.

Fixes: b6c159a9cb69 ("i2c: ismt: Don't duplicate the receive length for block reads")
Signed-off-by: Pontus Andersson 
Tested-by: Stephen Douthit 
Signed-off-by: Wolfram Sang 
Signed-off-by: Greg Kroah-Hartman

i2c: at91: ensure state is restored after suspending

2017-10-21T15:09:06+00:00

[ Upstream commit e3ccc921b7d8fd1fcd10a00720e09823d8078666 ]

When going to suspend, the I2C registers may be lost because the power to
VDDcore is cut. Restore them when resuming.

Signed-off-by: Alexandre Belloni 
Acked-by: Ludovic Desroches 
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

i2c: meson: fix wrong variable usage in meson_i2c_put_data

2017-10-08T08:14:20+00:00

[ Upstream commit 3b0277f198ac928f323c42e180680d2f79aa980d ]

Most likely a copy & paste error.

Signed-off-by: Heiner Kallweit 
Acked-by: Jerome Brunet 
Signed-off-by: Wolfram Sang 
Fixes: 30021e3707a7 ("i2c: add support for Amlogic Meson I2C controller")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

i2c: ismt: Return EMSGSIZE for block reads with bogus length

2017-09-07T06:34:09+00:00

commit ba201c4f5ebe13d7819081756378777d8153f23e upstream.

Compare the number of bytes actually seen on the wire to the byte
count field returned by the slave device.

Previously we just overwrote the byte count returned by the slave
with the real byte count and let the caller figure out if the
message was sane.

Signed-off-by: Stephen Douthit 
Tested-by: Dan Priamo 
Acked-by: Neil Horman 
Signed-off-by: Wolfram Sang 
Signed-off-by: Greg Kroah-Hartman

i2c: ismt: Don't duplicate the receive length for block reads

2017-09-07T06:34:08+00:00

commit b6c159a9cb69c2cf0bf59d4e12c3a2da77e4d994 upstream.

According to Table 15-14 of the C2000 EDS (Intel doc #510524) the
rx data pointed to by the descriptor dptr contains the byte count.

desc->rxbytes reports all bytes read on the wire, including the
"byte count" byte.  So if a device sends 4 bytes in response to a
block read, on the wire and in the DMA buffer we see:

count data1 data2 data3 data4
 0x04  0xde  0xad  0xbe  0xef

That's what we want to return in data->block to the next level.

Instead we were actually prefixing that with desc->rxbytes:

bad
count count data1 data2 data3 data4
 0x05  0x04  0xde  0xad  0xbe  0xef

This was discovered while developing a BMC solution relying on the
ipmi_ssif.c driver which was trying to interpret the bogus length
field as part of the IPMI response.

Signed-off-by: Stephen Douthit 
Tested-by: Dan Priamo 
Acked-by: Neil Horman 
Signed-off-by: Wolfram Sang 
Signed-off-by: Greg Kroah-Hartman

i2c: jz4780: drop superfluous init

2017-09-02T05:06:50+00:00

commit 27bfeb5a0619554d9734fb39e14f0e80fa7c342c upstream.

David reported that the length for memset was incorrect (element sizes
were not taken into account). Then I saw that we are clearing kzalloced
memory, so we can simply drop this code.

Reported-by: David Binderman 
Reviewed-by: Axel Lin 
Signed-off-by: Wolfram Sang 
Signed-off-by: Greg Kroah-Hartman