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Parker Newman 6557047017 misc: eeprom: eeprom_93cx6: Add quirk for extra read clock cycle 
[ Upstream commit 7738a7ab9d ]

Add a quirk similar to eeprom_93xx46 to add an extra clock cycle before
reading data from the EEPROM.

The 93Cx6 family of EEPROMs output a "dummy 0 bit" between the writing
of the op-code/address from the host to the EEPROM and the reading of
the actual data from the EEPROM.

More info can be found on page 6 of the AT93C46 datasheet (linked below).
Similar notes are found in other 93xx6 datasheets.

In summary the read operation for a 93Cx6 EEPROM is:
Write to EEPROM:	110[A5-A0]	(9 bits)
Read from EEPROM:	0[D15-D0]	(17 bits)

Where:
	110 is the start bit and READ OpCode
	[A5-A0] is the address to read from
	0 is a "dummy bit" preceding the actual data
	[D15-D0] is the actual data.

Looking at the READ timing diagrams in the 93Cx6 datasheets the dummy
bit should be clocked out on the last address bit clock cycle meaning it
should be discarded naturally.

However, depending on the hardware configuration sometimes this dummy
bit is not discarded. This is the case with Exar PCI UARTs which require
an extra clock cycle between sending the address and reading the data.

Datasheet: https://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-5193-SEEPROM-AT93C46D-Datasheet.pdf
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Parker Newman <pnewman@connecttech.com>
Link: https://lore.kernel.org/r/0f23973efefccd2544705a0480b4ad4c2353e407.1727880931.git.pnewman@connecttech.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
History 2024-12-14 20:04:09 +01:00
..
altera-stapl move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
bcm-vk move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
c2port c2port: replace deprecated strncpy with strscpy 2023-10-05 13:34:05 +02:00
cardreader misc: rtsx: list supported models in Kconfig help 2024-10-18 13:40:17 +02:00
cb710 cb710: avoid NULL pointer subtraction 2021-10-05 15:50:05 +02:00
cxl cxl: Constify struct kobj_type 2024-09-11 16:02:50 +02:00
echo char: Replace HTTP links with HTTPS ones 2020-07-23 09:44:15 +02:00
eeprom misc: eeprom: eeprom_93cx6: Add quirk for extra read clock cycle 2024-12-14 20:04:09 +01:00
genwqe mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER 2024-01-08 15:27:15 -08:00
ibmasm ibmasm: convert to new timestamp accessors 2023-10-18 13:26:16 +02:00
keba misc: keba: Fix sysfs group creation 2024-09-03 12:37:29 +02:00
lis3lv02d [tree-wide] finally take no_llseek out 2024-09-27 08:18:43 -07:00
lkdtm Compiler Attributes: disable __counted_by for clang < 19.1.3 2024-12-05 14:02:45 +01:00
mchp_pci1xxxx misc: microchip: pci1xxxx: add support for NVMEM_DEVID_AUTO for OTP device 2024-10-13 18:17:57 +02:00
mei mei: use kvmalloc for read buffer 2024-10-29 04:01:40 +01:00
ocxl ocxl: Remove the unused declarations in headr file 2024-09-11 16:03:20 +02:00
pvpanic Linux 6.9-rc7 2024-05-08 19:21:51 +01:00
sgi-gru misc: sgi-gru: Don't disable preemption in GRU driver 2024-10-09 12:47:01 -07:00
sgi-xp sysctl-6.7-rc1 2023-11-01 20:51:41 -10:00
ti-st misc: ti-st: st_kim: use 'time_left' variable with wait_for_completion_interruptible_timeout() 2024-07-03 16:40:18 +02:00
uacce uacce: make uacce_class constant 2023-10-27 08:51:00 +02:00
vmw_vmci VMCI: Fix use-after-free when removing resource in vmci_resource_remove() 2024-09-03 13:16:42 +02:00
ad525x_dpot-i2c.c misc: Switch i2c drivers back to use .probe() 2023-05-29 15:04:52 +01:00
ad525x_dpot-spi.c spi: make remove callback a void function 2022-02-09 13:00:45 +00:00
ad525x_dpot.c misc: ad525x_dpot: Make ad_dpot_remove() return void 2021-10-13 14:35:37 +02:00
ad525x_dpot.h misc: ad525x_dpot: Make ad_dpot_remove() return void 2021-10-13 14:35:37 +02:00
apds990x.c misc: apds990x: Fix missing pm_runtime_disable() 2024-12-05 14:02:36 +01:00
apds9802als.c misc: Drop explicit initialization of struct i2c_device_id::driver_data to 0 2024-07-03 16:41:00 +02:00
atmel-ssc.c misc: atmel-ssc: Convert to platform remove callback returning void 2024-03-05 14:28:51 +00:00
bh1770glc.c misc: Drop explicit initialization of struct i2c_device_id::driver_data to 0 2024-07-03 16:41:00 +02:00
cs5535-mfgpt.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206 2019-05-30 11:29:53 -07:00
ds1682.c misc: Drop explicit initialization of struct i2c_device_id::driver_data to 0 2024-07-03 16:41:00 +02:00
dummy-irq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
dw-xdata-pcie.c dw-xdata: Remove usage of the deprecated ida_simple_*() API 2023-12-31 11:09:26 +00:00
enclosure.c drivers: remove struct module * setting from struct class 2023-03-17 15:16:27 +01:00
fastrpc.c Merge 6.11-rc7 into char-misc-next 2024-09-09 08:36:23 +02:00
gehc-achc.c misc: gehc-achc: Follow renaming of SPI "master" to "controller" 2024-02-08 11:54:43 +00:00
hi6421v600-irq.c misc: hi6421-spmi-pmic: Remove unused of_gpio.h 2024-03-05 14:28:41 +00:00
hisi_hikey_usb.c misc: hisi_hikey_usb: Convert to platform remove callback returning void 2024-03-05 14:28:52 +00:00
hmc6352.c misc: Drop explicit initialization of struct i2c_device_id::driver_data to 0 2024-07-03 16:41:00 +02:00
hpilo.c misc: hpilo: rename device creation loop variable 2024-01-30 16:19:43 -08:00
hpilo.h misc: hpilo: map iLO shared memory by PCI revision id 2021-06-04 15:28:23 +02:00
ibmvmc.c Char/Misc and other driver changes for 6.7-rc1 2023-11-03 14:51:08 -10:00
ibmvmc.h misc: Use the correct style for SPDX License Identifier 2019-10-10 15:34:40 +02:00
ics932s401.c misc: Drop explicit initialization of struct i2c_device_id::driver_data to 0 2024-07-03 16:41:00 +02:00
isl29003.c misc: Drop explicit initialization of struct i2c_device_id::driver_data to 0 2024-07-03 16:41:00 +02:00
isl29020.c misc: Drop explicit initialization of struct i2c_device_id::driver_data to 0 2024-07-03 16:41:00 +02:00
Kconfig rpmb: add Replay Protected Memory Block (RPMB) subsystem 2024-08-26 13:16:20 +02:00
kgdbts.c kgdbts: fix hw_access_break_test 2024-08-13 11:27:38 +02:00
lattice-ecp3-config.c move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
Makefile rpmb: add Replay Protected Memory Block (RPMB) subsystem 2024-08-26 13:16:20 +02:00
mrvl_cn10k_dpi.c misc: mrvl-cn10k-dpi: add Octeon CN10K DPI administrative driver 2024-07-10 14:58:29 +02:00
nsm.c misc: nsm: drop owner assignment 2024-05-22 08:31:17 -04:00
ntsync.c [tree-wide] finally take no_llseek out 2024-09-27 08:18:43 -07:00
open-dice.c misc: open-dice: add missing MODULE_DESCRIPTION() macro 2024-06-04 17:40:20 +02:00
pch_phub.c misc: pch_phub: Remove superfluous descriptions to non-existent args 'offset_address' 2020-07-01 15:05:37 +02:00
pci_endpoint_test.c misc: pci_endpoint_test: Remove unused pci_endpoint_test_bar_{readl,writel} functions 2024-07-09 17:58:54 -05:00
phantom.c [tree-wide] finally take no_llseek out 2024-09-27 08:18:43 -07:00
qcom-coincell.c misc: Explicitly include correct DT includes 2023-08-04 15:39:04 +02:00
rpmb-core.c rpmb: fix error path in rpmb_dev_register() 2024-09-04 15:04:57 +02:00
smpro-errmon.c misc: smpro-errmon: Remove the unneeded include <linux/i2c.h> 2023-05-31 19:00:10 +01:00
smpro-misc.c misc: smpro-misc: Add Ampere's Altra SMpro misc driver 2022-11-10 19:03:03 +01:00
sram-exec.c mm: Introduce set_memory_rox() 2022-12-15 10:37:26 -08:00
sram.c misc: sram: Convert to platform remove callback returning void 2024-03-05 14:28:52 +00:00
sram.h misc: sram: Improve and simplify clk handling 2023-03-09 17:31:53 +01:00
tifm_7xx1.c misc: tifm: use 'time_left' variable with wait_for_completion_timeout() 2024-07-03 16:40:18 +02:00
tifm_core.c driver core: have match() callback in struct bus_type take a const * 2024-07-03 15:16:54 +02:00
tps6594-esm.c Merge 6.5-rc6 into char-misc-next 2023-08-13 22:14:51 +02:00
tps6594-pfsm.c misc: tps6594-pfsm: Add TI TPS65224 PMIC PFSM 2024-05-03 10:07:07 +01:00
tsl2550.c misc: tsl2550: replace simple_strtoul to kstrtoul 2024-09-03 12:34:31 +02:00
vcpu_stall_detector.c misc: Register a PPI for the vcpu stall detection virtual device 2024-07-04 12:31:22 +02:00
vmw_balloon.c vmw_balloon: dynamically allocate the vmw-balloon shrinker 2023-10-04 10:32:25 -07:00
xilinx_sdfec.c misc: xilinx_sdfec: Convert to platform remove callback returning void 2024-03-05 14:28:52 +00:00
xilinx_tmr_inject.c fault-inject: improve build for CONFIG_FAULT_INJECTION=n 2024-09-01 20:43:33 -07:00
xilinx_tmr_manager.c misc: Explicitly include correct DT includes 2023-08-04 15:39:04 +02:00