linux/drivers/i2c
Robert Hancock 4ca8ca873d i2c: cadence: Change large transfer count reset logic to be unconditional
Problems were observed on the Xilinx ZynqMP platform with large I2C reads.
When a read of 277 bytes was performed, the controller NAKed the transfer
after only 252 bytes were transferred and returned an ENXIO error on the
transfer.

There is some code in cdns_i2c_master_isr to handle this case by resetting
the transfer count in the controller before it reaches 0, to allow larger
transfers to work, but it was conditional on the CDNS_I2C_BROKEN_HOLD_BIT
quirk being set on the controller, and ZynqMP uses the r1p14 version of
the core where this quirk is not being set. The requirement to do this to
support larger reads seems like an inherently required workaround due to
the core only having an 8-bit transfer size register, so it does not
appear that this should be conditional on the broken HOLD bit quirk which
is used elsewhere in the driver.

Remove the dependency on the CDNS_I2C_BROKEN_HOLD_BIT for this transfer
size reset logic to fix this problem.

Fixes: 63cab195bf ("i2c: removed work arounds in i2c driver for Zynq Ultrascale+ MPSoC")
Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Reviewed-by: Shubhrajyoti Datta <Shubhrajyoti.datta@amd.com>
Acked-by: Michal Simek <michal.simek@amd.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-07-16 14:44:12 +02:00
..
algos i2c: algo: bit: use new macro to specifiy capabilities 2021-01-22 09:59:21 +01:00
busses i2c: cadence: Change large transfer count reset logic to be unconditional 2022-07-16 14:44:12 +02:00
muxes i2c: mux: demux-pinctrl: do not deactivate a master that is not active 2022-03-20 00:49:43 +01:00
i2c-boardinfo.c i2c: Remove support for dangling device properties 2021-04-10 21:43:02 +02:00
i2c-core-acpi.c i2c: ACPI: Replace acpi_bus_get_device() 2022-02-07 17:00:08 +01:00
i2c-core-base.c i2c: core: Use generic_handle_irq_safe() in i2c_handle_smbus_host_notify(). 2022-03-01 15:58:41 +01:00
i2c-core-of.c i2c: use my kernel.org address from now on 2020-05-05 16:29:09 +02:00
i2c-core-slave.c i2c: add tracepoints for I2C slave events 2022-03-20 00:11:05 +01:00
i2c-core-smbus.c i2c: smbus: Check for parent device before dereference 2022-02-19 12:37:20 +01:00
i2c-core.h i2c: don't expose function which is only used internally 2022-02-15 09:58:57 +01:00
i2c-dev.c i2c: dev: Force case user pointers in compat_i2cdev_ioctl() 2022-04-15 23:30:59 +02:00
i2c-mux.c i2c: mux: add sysfs header 2019-06-22 07:32:33 +02:00
i2c-slave-eeprom.c i2c: busses: Use fallthrough pseudo-keyword 2020-07-23 22:04:08 +02:00
i2c-slave-testunit.c i2c: testunit: add support for block process calls 2021-02-12 11:11:04 +01:00
i2c-smbus.c i2c: smbus: Use device_*() functions instead of of_*() 2022-01-28 21:56:34 +01:00
i2c-stub.c i2c: stub: remove definition of DEBUG 2021-01-17 13:00:10 +01:00
Kconfig i2c: add slave testunit driver 2020-09-21 11:02:17 +02:00
Makefile i2c: add slave testunit driver 2020-09-21 11:02:17 +02:00