From: Ivo van Doorn Date: Fri, 11 May 2007 19:59:40 +0000 (-0400) Subject: [PATCH] Add 93cx6 eeprom library X-Git-Tag: v2.6.23-rc1~1201^2~74 X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Ftorvalds%2Flinux-2.6.git;a=commitdiff_plain;h=9467d64b0e88763914c01f71ddf591b166c4f526 [PATCH] Add 93cx6 eeprom library This patch adds a library for reading from 93cx6 eeproms. Signed-off-by: Michael Wu Signed-off-by: John W. Linville --- diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index 616eee9..bd601ef 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -34,6 +34,11 @@ config PHANTOM If you choose to build module, its name will be phantom. If unsure, say N here. +config EEPROM_93CX6 + tristate "EEPROM 93CX6 support" + ---help--- + This is a driver for the EEPROM chipsets 93c46 and 93c66. + The driver supports both read as well as write commands. If unsure, say N. @@ -187,5 +192,4 @@ config THINKPAD_ACPI_BAY If you are not sure, say Y here. - endmenu diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index 8abbf2f..b5ce0e3 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -14,3 +14,4 @@ obj-$(CONFIG_PHANTOM) += phantom.o obj-$(CONFIG_SGI_IOC4) += ioc4.o obj-$(CONFIG_SONY_LAPTOP) += sony-laptop.o obj-$(CONFIG_THINKPAD_ACPI) += thinkpad_acpi.o +obj-$(CONFIG_EEPROM_93CX6) += eeprom_93cx6.o diff --git a/drivers/misc/eeprom_93cx6.c b/drivers/misc/eeprom_93cx6.c new file mode 100644 index 0000000..bfcb434 --- /dev/null +++ b/drivers/misc/eeprom_93cx6.c @@ -0,0 +1,229 @@ +/* + Copyright (C) 2004 - 2006 rt2x00 SourceForge Project + + + 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. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the + Free Software Foundation, Inc., + 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +/* + Module: eeprom_93cx6 + Abstract: EEPROM reader routines for 93cx6 chipsets. + Supported chipsets: 93c46 & 93c66. + */ + +#include +#include +#include +#include +#include + +MODULE_AUTHOR("http://rt2x00.serialmonkey.com"); +MODULE_VERSION("1.0"); +MODULE_DESCRIPTION("EEPROM 93cx6 chip driver"); +MODULE_LICENSE("GPL"); + +static inline void eeprom_93cx6_pulse_high(struct eeprom_93cx6 *eeprom) +{ + eeprom->reg_data_clock = 1; + eeprom->register_write(eeprom); + udelay(1); +} + +static inline void eeprom_93cx6_pulse_low(struct eeprom_93cx6 *eeprom) +{ + eeprom->reg_data_clock = 0; + eeprom->register_write(eeprom); + udelay(1); +} + +static void eeprom_93cx6_startup(struct eeprom_93cx6 *eeprom) +{ + /* + * Clear all flags, and enable chip select. + */ + eeprom->register_read(eeprom); + eeprom->reg_data_in = 0; + eeprom->reg_data_out = 0; + eeprom->reg_data_clock = 0; + eeprom->reg_chip_select = 1; + eeprom->register_write(eeprom); + + /* + * kick a pulse. + */ + eeprom_93cx6_pulse_high(eeprom); + eeprom_93cx6_pulse_low(eeprom); +} + +static void eeprom_93cx6_cleanup(struct eeprom_93cx6 *eeprom) +{ + /* + * Clear chip_select and data_in flags. + */ + eeprom->register_read(eeprom); + eeprom->reg_data_in = 0; + eeprom->reg_chip_select = 0; + eeprom->register_write(eeprom); + + /* + * kick a pulse. + */ + eeprom_93cx6_pulse_high(eeprom); + eeprom_93cx6_pulse_low(eeprom); +} + +static void eeprom_93cx6_write_bits(struct eeprom_93cx6 *eeprom, + const u16 data, const u16 count) +{ + unsigned int i; + + eeprom->register_read(eeprom); + + /* + * Clear data flags. + */ + eeprom->reg_data_in = 0; + eeprom->reg_data_out = 0; + + /* + * Start writing all bits. + */ + for (i = count; i > 0; i--) { + /* + * Check if this bit needs to be set. + */ + eeprom->reg_data_in = !!(data & (1 << (i - 1))); + + /* + * Write the bit to the eeprom register. + */ + eeprom->register_write(eeprom); + + /* + * Kick a pulse. + */ + eeprom_93cx6_pulse_high(eeprom); + eeprom_93cx6_pulse_low(eeprom); + } + + eeprom->reg_data_in = 0; + eeprom->register_write(eeprom); +} + +static void eeprom_93cx6_read_bits(struct eeprom_93cx6 *eeprom, + u16 *data, const u16 count) +{ + unsigned int i; + u16 buf = 0; + + eeprom->register_read(eeprom); + + /* + * Clear data flags. + */ + eeprom->reg_data_in = 0; + eeprom->reg_data_out = 0; + + /* + * Start reading all bits. + */ + for (i = count; i > 0; i--) { + eeprom_93cx6_pulse_high(eeprom); + + eeprom->register_read(eeprom); + + /* + * Clear data_in flag. + */ + eeprom->reg_data_in = 0; + + /* + * Read if the bit has been set. + */ + if (eeprom->reg_data_out) + buf |= (1 << (i - 1)); + + eeprom_93cx6_pulse_low(eeprom); + } + + *data = buf; +} + +/** + * eeprom_93cx6_read - Read multiple words from eeprom + * @eeprom: Pointer to eeprom structure + * @word: Word index from where we should start reading + * @data: target pointer where the information will have to be stored + * + * This function will read the eeprom data as host-endian word + * into the given data pointer. + */ +void eeprom_93cx6_read(struct eeprom_93cx6 *eeprom, const u8 word, + u16 *data) +{ + u16 command; + + /* + * Initialize the eeprom register + */ + eeprom_93cx6_startup(eeprom); + + /* + * Select the read opcode and the word to be read. + */ + command = (PCI_EEPROM_READ_OPCODE << eeprom->width) | word; + eeprom_93cx6_write_bits(eeprom, command, + PCI_EEPROM_WIDTH_OPCODE + eeprom->width); + + /* + * Read the requested 16 bits. + */ + eeprom_93cx6_read_bits(eeprom, data, 16); + + /* + * Cleanup eeprom register. + */ + eeprom_93cx6_cleanup(eeprom); +} +EXPORT_SYMBOL_GPL(eeprom_93cx6_read); + +/** + * eeprom_93cx6_multiread - Read multiple words from eeprom + * @eeprom: Pointer to eeprom structure + * @word: Word index from where we should start reading + * @data: target pointer where the information will have to be stored + * @words: Number of words that should be read. + * + * This function will read all requested words from the eeprom, + * this is done by calling eeprom_93cx6_read() multiple times. + * But with the additional change that while the eeprom_93cx6_read + * will return host ordered bytes, this method will return little + * endian words. + */ +void eeprom_93cx6_multiread(struct eeprom_93cx6 *eeprom, const u8 word, + __le16 *data, const u16 words) +{ + unsigned int i; + u16 tmp; + + for (i = 0; i < words; i++) { + tmp = 0; + eeprom_93cx6_read(eeprom, word + i, &tmp); + data[i] = cpu_to_le16(tmp); + } +} +EXPORT_SYMBOL_GPL(eeprom_93cx6_multiread); + diff --git a/include/linux/eeprom_93cx6.h b/include/linux/eeprom_93cx6.h new file mode 100644 index 0000000..d774b77 --- /dev/null +++ b/include/linux/eeprom_93cx6.h @@ -0,0 +1,72 @@ +/* + Copyright (C) 2004 - 2006 rt2x00 SourceForge Project + + + 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. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the + Free Software Foundation, Inc., + 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +/* + Module: eeprom_93cx6 + Abstract: EEPROM reader datastructures for 93cx6 chipsets. + Supported chipsets: 93c46 & 93c66. + */ + +/* + * EEPROM operation defines. + */ +#define PCI_EEPROM_WIDTH_93C46 6 +#define PCI_EEPROM_WIDTH_93C66 8 +#define PCI_EEPROM_WIDTH_OPCODE 3 +#define PCI_EEPROM_WRITE_OPCODE 0x05 +#define PCI_EEPROM_READ_OPCODE 0x06 +#define PCI_EEPROM_EWDS_OPCODE 0x10 +#define PCI_EEPROM_EWEN_OPCODE 0x13 + +/** + * struct eeprom_93cx6 - control structure for setting the commands + * for reading the eeprom data. + * @data: private pointer for the driver. + * @register_read(struct eeprom_93cx6 *eeprom): handler to + * read the eeprom register, this function should set all reg_* fields. + * @register_write(struct eeprom_93cx6 *eeprom): handler to + * write to the eeprom register by using all reg_* fields. + * @width: eeprom width, should be one of the PCI_EEPROM_WIDTH_* defines + * @reg_data_in: register field to indicate data input + * @reg_data_out: register field to indicate data output + * @reg_data_clock: register field to set the data clock + * @reg_chip_select: register field to set the chip select + * + * This structure is used for the communication between the driver + * and the eeprom_93cx6 handlers for reading the eeprom. + */ +struct eeprom_93cx6 { + void *data; + + void (*register_read)(struct eeprom_93cx6 *eeprom); + void (*register_write)(struct eeprom_93cx6 *eeprom); + + int width; + + char reg_data_in; + char reg_data_out; + char reg_data_clock; + char reg_chip_select; +}; + +extern void eeprom_93cx6_read(struct eeprom_93cx6 *eeprom, + const u8 word, u16 *data); +extern void eeprom_93cx6_multiread(struct eeprom_93cx6 *eeprom, + const u8 word, __le16 *data, const u16 words);