Ivo van Doorn | 9467d64 | 2007-05-11 15:59:40 -0400 | [diff] [blame^] | 1 | /* |
| 2 | Copyright (C) 2004 - 2006 rt2x00 SourceForge Project |
| 3 | <http://rt2x00.serialmonkey.com> |
| 4 | |
| 5 | This program is free software; you can redistribute it and/or modify |
| 6 | it under the terms of the GNU General Public License as published by |
| 7 | the Free Software Foundation; either version 2 of the License, or |
| 8 | (at your option) any later version. |
| 9 | |
| 10 | This program is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | GNU General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU General Public License |
| 16 | along with this program; if not, write to the |
| 17 | Free Software Foundation, Inc., |
| 18 | 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 19 | */ |
| 20 | |
| 21 | /* |
| 22 | Module: eeprom_93cx6 |
| 23 | Abstract: EEPROM reader routines for 93cx6 chipsets. |
| 24 | Supported chipsets: 93c46 & 93c66. |
| 25 | */ |
| 26 | |
| 27 | #include <linux/kernel.h> |
| 28 | #include <linux/module.h> |
| 29 | #include <linux/version.h> |
| 30 | #include <linux/delay.h> |
| 31 | #include <linux/eeprom_93cx6.h> |
| 32 | |
| 33 | MODULE_AUTHOR("http://rt2x00.serialmonkey.com"); |
| 34 | MODULE_VERSION("1.0"); |
| 35 | MODULE_DESCRIPTION("EEPROM 93cx6 chip driver"); |
| 36 | MODULE_LICENSE("GPL"); |
| 37 | |
| 38 | static inline void eeprom_93cx6_pulse_high(struct eeprom_93cx6 *eeprom) |
| 39 | { |
| 40 | eeprom->reg_data_clock = 1; |
| 41 | eeprom->register_write(eeprom); |
| 42 | udelay(1); |
| 43 | } |
| 44 | |
| 45 | static inline void eeprom_93cx6_pulse_low(struct eeprom_93cx6 *eeprom) |
| 46 | { |
| 47 | eeprom->reg_data_clock = 0; |
| 48 | eeprom->register_write(eeprom); |
| 49 | udelay(1); |
| 50 | } |
| 51 | |
| 52 | static void eeprom_93cx6_startup(struct eeprom_93cx6 *eeprom) |
| 53 | { |
| 54 | /* |
| 55 | * Clear all flags, and enable chip select. |
| 56 | */ |
| 57 | eeprom->register_read(eeprom); |
| 58 | eeprom->reg_data_in = 0; |
| 59 | eeprom->reg_data_out = 0; |
| 60 | eeprom->reg_data_clock = 0; |
| 61 | eeprom->reg_chip_select = 1; |
| 62 | eeprom->register_write(eeprom); |
| 63 | |
| 64 | /* |
| 65 | * kick a pulse. |
| 66 | */ |
| 67 | eeprom_93cx6_pulse_high(eeprom); |
| 68 | eeprom_93cx6_pulse_low(eeprom); |
| 69 | } |
| 70 | |
| 71 | static void eeprom_93cx6_cleanup(struct eeprom_93cx6 *eeprom) |
| 72 | { |
| 73 | /* |
| 74 | * Clear chip_select and data_in flags. |
| 75 | */ |
| 76 | eeprom->register_read(eeprom); |
| 77 | eeprom->reg_data_in = 0; |
| 78 | eeprom->reg_chip_select = 0; |
| 79 | eeprom->register_write(eeprom); |
| 80 | |
| 81 | /* |
| 82 | * kick a pulse. |
| 83 | */ |
| 84 | eeprom_93cx6_pulse_high(eeprom); |
| 85 | eeprom_93cx6_pulse_low(eeprom); |
| 86 | } |
| 87 | |
| 88 | static void eeprom_93cx6_write_bits(struct eeprom_93cx6 *eeprom, |
| 89 | const u16 data, const u16 count) |
| 90 | { |
| 91 | unsigned int i; |
| 92 | |
| 93 | eeprom->register_read(eeprom); |
| 94 | |
| 95 | /* |
| 96 | * Clear data flags. |
| 97 | */ |
| 98 | eeprom->reg_data_in = 0; |
| 99 | eeprom->reg_data_out = 0; |
| 100 | |
| 101 | /* |
| 102 | * Start writing all bits. |
| 103 | */ |
| 104 | for (i = count; i > 0; i--) { |
| 105 | /* |
| 106 | * Check if this bit needs to be set. |
| 107 | */ |
| 108 | eeprom->reg_data_in = !!(data & (1 << (i - 1))); |
| 109 | |
| 110 | /* |
| 111 | * Write the bit to the eeprom register. |
| 112 | */ |
| 113 | eeprom->register_write(eeprom); |
| 114 | |
| 115 | /* |
| 116 | * Kick a pulse. |
| 117 | */ |
| 118 | eeprom_93cx6_pulse_high(eeprom); |
| 119 | eeprom_93cx6_pulse_low(eeprom); |
| 120 | } |
| 121 | |
| 122 | eeprom->reg_data_in = 0; |
| 123 | eeprom->register_write(eeprom); |
| 124 | } |
| 125 | |
| 126 | static void eeprom_93cx6_read_bits(struct eeprom_93cx6 *eeprom, |
| 127 | u16 *data, const u16 count) |
| 128 | { |
| 129 | unsigned int i; |
| 130 | u16 buf = 0; |
| 131 | |
| 132 | eeprom->register_read(eeprom); |
| 133 | |
| 134 | /* |
| 135 | * Clear data flags. |
| 136 | */ |
| 137 | eeprom->reg_data_in = 0; |
| 138 | eeprom->reg_data_out = 0; |
| 139 | |
| 140 | /* |
| 141 | * Start reading all bits. |
| 142 | */ |
| 143 | for (i = count; i > 0; i--) { |
| 144 | eeprom_93cx6_pulse_high(eeprom); |
| 145 | |
| 146 | eeprom->register_read(eeprom); |
| 147 | |
| 148 | /* |
| 149 | * Clear data_in flag. |
| 150 | */ |
| 151 | eeprom->reg_data_in = 0; |
| 152 | |
| 153 | /* |
| 154 | * Read if the bit has been set. |
| 155 | */ |
| 156 | if (eeprom->reg_data_out) |
| 157 | buf |= (1 << (i - 1)); |
| 158 | |
| 159 | eeprom_93cx6_pulse_low(eeprom); |
| 160 | } |
| 161 | |
| 162 | *data = buf; |
| 163 | } |
| 164 | |
| 165 | /** |
| 166 | * eeprom_93cx6_read - Read multiple words from eeprom |
| 167 | * @eeprom: Pointer to eeprom structure |
| 168 | * @word: Word index from where we should start reading |
| 169 | * @data: target pointer where the information will have to be stored |
| 170 | * |
| 171 | * This function will read the eeprom data as host-endian word |
| 172 | * into the given data pointer. |
| 173 | */ |
| 174 | void eeprom_93cx6_read(struct eeprom_93cx6 *eeprom, const u8 word, |
| 175 | u16 *data) |
| 176 | { |
| 177 | u16 command; |
| 178 | |
| 179 | /* |
| 180 | * Initialize the eeprom register |
| 181 | */ |
| 182 | eeprom_93cx6_startup(eeprom); |
| 183 | |
| 184 | /* |
| 185 | * Select the read opcode and the word to be read. |
| 186 | */ |
| 187 | command = (PCI_EEPROM_READ_OPCODE << eeprom->width) | word; |
| 188 | eeprom_93cx6_write_bits(eeprom, command, |
| 189 | PCI_EEPROM_WIDTH_OPCODE + eeprom->width); |
| 190 | |
| 191 | /* |
| 192 | * Read the requested 16 bits. |
| 193 | */ |
| 194 | eeprom_93cx6_read_bits(eeprom, data, 16); |
| 195 | |
| 196 | /* |
| 197 | * Cleanup eeprom register. |
| 198 | */ |
| 199 | eeprom_93cx6_cleanup(eeprom); |
| 200 | } |
| 201 | EXPORT_SYMBOL_GPL(eeprom_93cx6_read); |
| 202 | |
| 203 | /** |
| 204 | * eeprom_93cx6_multiread - Read multiple words from eeprom |
| 205 | * @eeprom: Pointer to eeprom structure |
| 206 | * @word: Word index from where we should start reading |
| 207 | * @data: target pointer where the information will have to be stored |
| 208 | * @words: Number of words that should be read. |
| 209 | * |
| 210 | * This function will read all requested words from the eeprom, |
| 211 | * this is done by calling eeprom_93cx6_read() multiple times. |
| 212 | * But with the additional change that while the eeprom_93cx6_read |
| 213 | * will return host ordered bytes, this method will return little |
| 214 | * endian words. |
| 215 | */ |
| 216 | void eeprom_93cx6_multiread(struct eeprom_93cx6 *eeprom, const u8 word, |
| 217 | __le16 *data, const u16 words) |
| 218 | { |
| 219 | unsigned int i; |
| 220 | u16 tmp; |
| 221 | |
| 222 | for (i = 0; i < words; i++) { |
| 223 | tmp = 0; |
| 224 | eeprom_93cx6_read(eeprom, word + i, &tmp); |
| 225 | data[i] = cpu_to_le16(tmp); |
| 226 | } |
| 227 | } |
| 228 | EXPORT_SYMBOL_GPL(eeprom_93cx6_multiread); |
| 229 | |