linux-stable/drivers/i2c
Stephen Douthit b6c159a9cb i2c: ismt: Don't duplicate the receive length for block reads
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 <stephend@adiengineering.com>
Tested-by: Dan Priamo <danp@adiengineering.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2017-08-29 22:12:30 +02:00
..
algos i2c: algo-bit: add support for I2C_M_STOP 2017-06-23 20:45:43 +02:00
busses i2c: ismt: Don't duplicate the receive length for block reads 2017-08-29 22:12:30 +02:00
muxes i2c: mux: pinctrl: mention correct module name in Kconfig help text 2017-07-17 06:24:37 +02:00
i2c-boardinfo.c i2c: allow attaching IRQ resources to i2c_board_info 2017-04-01 09:36:19 -07:00
i2c-core-acpi.c i2c: core: Allow empty id_table in ACPI case as well 2017-07-31 15:50:33 +02:00
i2c-core-base.c i2c: core: Make comment about I2C table requirement to reflect the code 2017-08-14 21:33:46 +02:00
i2c-core-of.c i2c: break out OF support into separate file 2017-05-31 21:01:04 +02:00
i2c-core-slave.c i2c: break out slave support into separate file 2017-05-31 21:01:03 +02:00
i2c-core-smbus.c i2c: break out smbus support into separate file 2017-05-31 21:01:03 +02:00
i2c-core.h i2c: core: Allow empty id_table in ACPI case as well 2017-07-31 15:50:33 +02:00
i2c-dev.c i2c: fix kernel memory disclosure in dev interface 2017-01-12 20:06:10 +01:00
i2c-mux.c i2c: mux: only print failure message on error 2017-05-15 18:49:11 +02:00
i2c-slave-eeprom.c
i2c-smbus.c i2c: use an IRQ to report Host Notify events, not alert 2016-11-24 16:22:06 +01:00
i2c-stub.c i2c: stub: fix build warning regression 2017-06-15 23:22:11 +02:00
Kconfig Merge branch 'i2c/for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2016-12-15 12:56:35 -08:00
Makefile i2c: break out ACPI support into separate file 2017-05-31 21:01:04 +02:00