linux/drivers/i2c
Ondrej Jirman 02fe0fbd8a i2c: rk3x: Handle a spurious start completion interrupt flag
In a typical read transfer, start completion flag is being set after
read finishes (notice ipd bit 4 being set):

trasnfer poll=0
i2c start
rk3x-i2c fdd40000.i2c: IRQ: state 1, ipd: 10
i2c read
rk3x-i2c fdd40000.i2c: IRQ: state 2, ipd: 1b
i2c stop
rk3x-i2c fdd40000.i2c: IRQ: state 4, ipd: 33

This causes I2C transfer being aborted in polled mode from a stop completion
handler:

trasnfer poll=1
i2c start
rk3x-i2c fdd40000.i2c: IRQ: state 1, ipd: 10
i2c read
rk3x-i2c fdd40000.i2c: IRQ: state 2, ipd: 0
rk3x-i2c fdd40000.i2c: IRQ: state 2, ipd: 1b
i2c stop
rk3x-i2c fdd40000.i2c: IRQ: state 4, ipd: 13
i2c stop
rk3x-i2c fdd40000.i2c: unexpected irq in STOP: 0x10

Clearing the START flag after read fixes the issue without any obvious
side effects.

This issue was dicovered on RK3566 when adding support for powering
off the RK817 PMIC.

Signed-off-by: Ondrej Jirman <megous@megous.com>
Reviewed-by: John Keeping <john@metanate.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2021-11-30 22:38:15 +01:00
..
algos i2c: algo: bit: use new macro to specifiy capabilities 2021-01-22 09:59:21 +01:00
busses i2c: rk3x: Handle a spurious start completion interrupt flag 2021-11-30 22:38:15 +01:00
muxes i2c: muxes: i2c-arb-gpio-challenge: Demote non-conformant kernel-doc headers 2021-05-27 21:29:03 +02:00
i2c-boardinfo.c i2c: Remove support for dangling device properties 2021-04-10 21:43:02 +02:00
i2c-core-acpi.c More ACPI updates for 5.16-rc1 2021-11-10 11:52:40 -08:00
i2c-core-base.c i2c: Allow an ACPI driver to manage the device's power state during probe 2021-11-03 19:03:55 +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: slave: add sanity check when unregistering 2020-07-28 18:37:17 +02:00
i2c-core-smbus.c i2c: core-smbus: Expose PEC calculate function for generic use 2021-06-25 17:09:34 +02:00
i2c-core.h i2c: acpi: Remove dead code, i.e. i2c_acpi_match_device() 2020-08-25 09:22:09 +02:00
i2c-dev.c Merge branch 'i2c/for-mergewindow' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2021-08-31 14:34:01 -07:00
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: add core function handling SMBus host-notify 2020-09-09 10:38:28 +02:00
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