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Diffstat (limited to 'drivers/misc/eeprom_93cx6.c')
-rw-r--r-- | drivers/misc/eeprom_93cx6.c | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/drivers/misc/eeprom_93cx6.c b/drivers/misc/eeprom_93cx6.c new file mode 100644 index 000000000000..bfcb43424dcd --- /dev/null +++ b/drivers/misc/eeprom_93cx6.c | |||
@@ -0,0 +1,229 @@ | |||
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 | |||