Wang Xin 9a9e295e7c eeprom: at24: fix unexpected timeout under high load ... Within at24_loop_until_timeout the timestamp used for timeout checking is recorded after the I2C transfer and sleep_range(). Under high CPU load either the execution time for I2C transfer or sleep_range() could actually be larger than the timeout value. Worst case the I2C transfer is only tried once because the loop will exit due to the timeout although the EEPROM is now ready. To fix this issue the timestamp is recorded at the beginning of each iteration. That is, before I2C transfer and sleep. Then the timeout is actually checked against the timestamp of the previous iteration. This makes sure that even if the timeout is reached, there is still one more chance to try the I2C transfer in case the EEPROM is ready. Example: If you have a system which combines high CPU load with repeated EEPROM writes you will run into the following scenario. - System makes a successful regmap_bulk_write() to EEPROM. - System wants to perform another write to EEPROM but EEPROM is still busy with the last write. - Because of high CPU load the usleep_range() will sleep more than 25 ms (at24_write_timeout). - Within the over-long sleeping the EEPROM finished the previous write operation and is ready again. - at24_loop_until_timeout() will detect timeout and won't try to write. Signed-off-by: Wang Xin <xin.wang7@cn.bosch.com> Signed-off-by: Mark Jonas <mark.jonas@de.bosch.com> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>		2018-10-02 16:58:21 +02:00
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altera-stapl
c2port
cardreader
cb710	cb710: Convert to new IDA API	2018-08-21 23:54:18 -04:00
cxl
echo
eeprom	eeprom: at24: fix unexpected timeout under high load	2018-10-02 16:58:21 +02:00
genwqe
ibmasm
lis3lv02d
lkdtm
mei	mei: bus: need to unlink client before freeing	2018-09-12 09:14:24 +02:00
mic	mm, oom: distinguish blockable mode for mmu notifiers	2018-08-22 10:52:44 -07:00
ocxl
sgi-gru	mm, oom: distinguish blockable mode for mmu notifiers	2018-08-22 10:52:44 -07:00
sgi-xp
ti-st
vmw_vmci
ad525x_dpot-i2c.c
ad525x_dpot-spi.c
ad525x_dpot.c
ad525x_dpot.h
apds990x.c
apds9802als.c
aspeed-lpc-ctrl.c
aspeed-lpc-snoop.c
atmel_tclib.c
atmel-ssc.c
bh1770glc.c
cs5535-mfgpt.c
ds1682.c
dummy-irq.c
enclosure.c
fsa9480.c
hmc6352.c	misc: hmc6352: fix potential Spectre v1	2018-09-12 09:31:00 +02:00
hpilo.c
hpilo.h
ibmvmc.c	misc: ibmvsm: Fix wrong assignment of return code	2018-09-12 09:31:00 +02:00
ibmvmc.h
ics932s401.c
ioc4.c
isl29003.c
isl29020.c
Kconfig
kgdbts.c
lattice-ecp3-config.c
Makefile
pch_phub.c
pci_endpoint_test.c
phantom.c
pti.c
qcom-coincell.c
spear13xx_pcie_gadget.c
sram-exec.c
sram.c
sram.h
tifm_7xx1.c
tifm_core.c
tsl2550.c
vexpress-syscfg.c
vmw_balloon.c