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path: root/drivers/misc/eeprom/eeprom_93cx6.c
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2024-10-11misc: eeprom: eeprom_93cx6: Switch to BIT() macroParker Newman
Use the BIT() macro rather than (1 << (i - 1)). Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Parker Newman <pnewman@connecttech.com> Link: https://lore.kernel.org/r/f40d21d284816a62003975e237a58b489d77c7d4.1727880931.git.pnewman@connecttech.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-10-11misc: eeprom: eeprom_93cx6: Add quirk for extra read clock cycleParker Newman
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>
2020-06-29misc: eeprom: eeprom_93cx6: Repair function arg descriptionsLee Jones
Copy-paste issue. Looks like the kerneldoc style descriptions for these functions were taken from existing functions with slightly different argument names. Fixes the following W=1 warnings: drivers/misc/eeprom/eeprom_93cx6.c:239: warning: Function parameter or member 'byte' not described in 'eeprom_93cx6_readb' drivers/misc/eeprom/eeprom_93cx6.c:239: warning: Excess function parameter 'word' description in 'eeprom_93cx6_readb' drivers/misc/eeprom/eeprom_93cx6.c:280: warning: Function parameter or member 'bytes' not described in 'eeprom_93cx6_multireadb' drivers/misc/eeprom/eeprom_93cx6.c:280: warning: Excess function parameter 'words' description in 'eeprom_93cx6_multireadb' Cc: Wolfram Sang <wsa@kernel.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Lee Jones <lee.jones@linaro.org> Link: https://lore.kernel.org/r/20200626130525.389469-7-lee.jones@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157Thomas Gleixner
Based on 3 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version [author] [graeme] [gregory] [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema] [hk] [hemahk]@[ti] [com] this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1105 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-25eeprom-93cx6: Add (read-only) support for 8-bit modeOndrej Zary
Add read-only support for EEPROMs configured in 8-bit mode (ORG pin connected to GND). This will be used by wd719x driver. Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Christoph Hellwig <hch@lst.de>
2011-11-26eeprom_93cx6: Add write supportBen Dooks
Add support for writing data to EEPROM. Signed-off-by: Ben Dooks <ben@simtec.co.uk> Cc: Wolfram Sang <w.sang@pengutronix.de> Cc: Jean Delvare <khali@linux-fr.org> Cc: Linux Kernel <linux-kernel@vger.kernel.org> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-26eeprom_93cx6: Add data direction control.Ben Dooks
Some devices need to know if the data is to be output or read, so add a data direction into the eeprom structure to tell the driver whether the data line should be driven. The user in this case is the Micrel KS8851 which has a direction control for the EEPROM data line and thus needs to know whether to drive it (writing) or to tristate it for receiving. Signed-off-by: Ben Dooks <ben@simtec.co.uk> Cc: Wolfram Sang <w.sang@pengutronix.de> Cc: Jean Delvare <khali@linux-fr.org> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-14EEPROM: 93cx6: Header file cleanupArce, Abraham
Change eeprom_93cx6.c header file to format as in conventions Signed-off-by: Abraham Arce <x0066660@ti.com> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-01-26eeprom: Move 93cx6 eeprom driver to /drivers/misc/eepromWolfram Sang
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Jean Delvare <khali@linux-fr.org>