diff options
Diffstat (limited to 'drivers/misc/eeprom/eeprom_93cx6.c')
| -rw-r--r-- | drivers/misc/eeprom/eeprom_93cx6.c | 127 |
1 files changed, 104 insertions, 23 deletions
diff --git a/drivers/misc/eeprom/eeprom_93cx6.c b/drivers/misc/eeprom/eeprom_93cx6.c index 15b1780025c..0ff4b02177b 100644 --- a/drivers/misc/eeprom/eeprom_93cx6.c +++ b/drivers/misc/eeprom/eeprom_93cx6.c @@ -1,27 +1,20 @@ /* - Copyright (C) 2004 - 2006 rt2x00 SourceForge Project - <http://rt2x00.serialmonkey.com> - - 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. + * Copyright (C) 2004 - 2006 rt2x00 SourceForge Project + * <http://rt2x00.serialmonkey.com> + * + * 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. + * + * Module: eeprom_93cx6 + * Abstract: EEPROM reader routines for 93cx6 chipsets. + * Supported chipsets: 93c46 & 93c66. */ #include <linux/kernel.h> @@ -70,6 +63,7 @@ static void eeprom_93cx6_startup(struct eeprom_93cx6 *eeprom) eeprom->reg_data_out = 0; eeprom->reg_data_clock = 0; eeprom->reg_chip_select = 1; + eeprom->drive_data = 1; eeprom->register_write(eeprom); /* @@ -108,6 +102,7 @@ static void eeprom_93cx6_write_bits(struct eeprom_93cx6 *eeprom, */ eeprom->reg_data_in = 0; eeprom->reg_data_out = 0; + eeprom->drive_data = 1; /* * Start writing all bits. @@ -147,6 +142,7 @@ static void eeprom_93cx6_read_bits(struct eeprom_93cx6 *eeprom, */ eeprom->reg_data_in = 0; eeprom->reg_data_out = 0; + eeprom->drive_data = 0; /* * Start reading all bits. @@ -238,3 +234,88 @@ void eeprom_93cx6_multiread(struct eeprom_93cx6 *eeprom, const u8 word, } EXPORT_SYMBOL_GPL(eeprom_93cx6_multiread); +/** + * eeprom_93cx6_wren - set the write enable state + * @eeprom: Pointer to eeprom structure + * @enable: true to enable writes, otherwise disable writes + * + * Set the EEPROM write enable state to either allow or deny + * writes depending on the @enable value. + */ +void eeprom_93cx6_wren(struct eeprom_93cx6 *eeprom, bool enable) +{ + u16 command; + + /* start the command */ + eeprom_93cx6_startup(eeprom); + + /* create command to enable/disable */ + + command = enable ? PCI_EEPROM_EWEN_OPCODE : PCI_EEPROM_EWDS_OPCODE; + command <<= (eeprom->width - 2); + + eeprom_93cx6_write_bits(eeprom, command, + PCI_EEPROM_WIDTH_OPCODE + eeprom->width); + + eeprom_93cx6_cleanup(eeprom); +} +EXPORT_SYMBOL_GPL(eeprom_93cx6_wren); + +/** + * eeprom_93cx6_write - write data to the EEPROM + * @eeprom: Pointer to eeprom structure + * @addr: Address to write data to. + * @data: The data to write to address @addr. + * + * Write the @data to the specified @addr in the EEPROM and + * waiting for the device to finish writing. + * + * Note, since we do not expect large number of write operations + * we delay in between parts of the operation to avoid using excessive + * amounts of CPU time busy waiting. + */ +void eeprom_93cx6_write(struct eeprom_93cx6 *eeprom, u8 addr, u16 data) +{ + int timeout = 100; + u16 command; + + /* start the command */ + eeprom_93cx6_startup(eeprom); + + command = PCI_EEPROM_WRITE_OPCODE << eeprom->width; + command |= addr; + + /* send write command */ + eeprom_93cx6_write_bits(eeprom, command, + PCI_EEPROM_WIDTH_OPCODE + eeprom->width); + + /* send data */ + eeprom_93cx6_write_bits(eeprom, data, 16); + + /* get ready to check for busy */ + eeprom->drive_data = 0; + eeprom->reg_chip_select = 1; + eeprom->register_write(eeprom); + + /* wait at-least 250ns to get DO to be the busy signal */ + usleep_range(1000, 2000); + + /* wait for DO to go high to signify finish */ + + while (true) { + eeprom->register_read(eeprom); + + if (eeprom->reg_data_out) + break; + + usleep_range(1000, 2000); + + if (--timeout <= 0) { + printk(KERN_ERR "%s: timeout\n", __func__); + break; + } + } + + eeprom_93cx6_cleanup(eeprom); +} +EXPORT_SYMBOL_GPL(eeprom_93cx6_write); |