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v6.8
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Copyright (C) 2004 - 2006 rt2x00 SourceForge Project
  4 * <http://rt2x00.serialmonkey.com>
  5 *
  6 * Module: eeprom_93cx6
  7 * Abstract: EEPROM reader routines for 93cx6 chipsets.
  8 * Supported chipsets: 93c46 & 93c66.
  9 */
 10
 
 11#include <linux/kernel.h>
 12#include <linux/module.h>
 13#include <linux/delay.h>
 14#include <linux/eeprom_93cx6.h>
 15
 16MODULE_AUTHOR("http://rt2x00.serialmonkey.com");
 17MODULE_VERSION("1.0");
 18MODULE_DESCRIPTION("EEPROM 93cx6 chip driver");
 19MODULE_LICENSE("GPL");
 20
 21static inline void eeprom_93cx6_pulse_high(struct eeprom_93cx6 *eeprom)
 22{
 23	eeprom->reg_data_clock = 1;
 24	eeprom->register_write(eeprom);
 25
 26	/*
 27	 * Add a short delay for the pulse to work.
 28	 * According to the specifications the "maximum minimum"
 29	 * time should be 450ns.
 30	 */
 31	ndelay(450);
 32}
 33
 34static inline void eeprom_93cx6_pulse_low(struct eeprom_93cx6 *eeprom)
 35{
 36	eeprom->reg_data_clock = 0;
 37	eeprom->register_write(eeprom);
 38
 39	/*
 40	 * Add a short delay for the pulse to work.
 41	 * According to the specifications the "maximum minimum"
 42	 * time should be 450ns.
 43	 */
 44	ndelay(450);
 45}
 46
 47static void eeprom_93cx6_startup(struct eeprom_93cx6 *eeprom)
 48{
 49	/*
 50	 * Clear all flags, and enable chip select.
 51	 */
 52	eeprom->register_read(eeprom);
 53	eeprom->reg_data_in = 0;
 54	eeprom->reg_data_out = 0;
 55	eeprom->reg_data_clock = 0;
 56	eeprom->reg_chip_select = 1;
 57	eeprom->drive_data = 1;
 58	eeprom->register_write(eeprom);
 59
 60	/*
 61	 * kick a pulse.
 62	 */
 63	eeprom_93cx6_pulse_high(eeprom);
 64	eeprom_93cx6_pulse_low(eeprom);
 65}
 66
 67static void eeprom_93cx6_cleanup(struct eeprom_93cx6 *eeprom)
 68{
 69	/*
 70	 * Clear chip_select and data_in flags.
 71	 */
 72	eeprom->register_read(eeprom);
 73	eeprom->reg_data_in = 0;
 74	eeprom->reg_chip_select = 0;
 75	eeprom->register_write(eeprom);
 76
 77	/*
 78	 * kick a pulse.
 79	 */
 80	eeprom_93cx6_pulse_high(eeprom);
 81	eeprom_93cx6_pulse_low(eeprom);
 82}
 83
 84static void eeprom_93cx6_write_bits(struct eeprom_93cx6 *eeprom,
 85	const u16 data, const u16 count)
 86{
 87	unsigned int i;
 88
 89	eeprom->register_read(eeprom);
 90
 91	/*
 92	 * Clear data flags.
 93	 */
 94	eeprom->reg_data_in = 0;
 95	eeprom->reg_data_out = 0;
 96	eeprom->drive_data = 1;
 97
 98	/*
 99	 * Start writing all bits.
100	 */
101	for (i = count; i > 0; i--) {
102		/*
103		 * Check if this bit needs to be set.
104		 */
105		eeprom->reg_data_in = !!(data & (1 << (i - 1)));
106
107		/*
108		 * Write the bit to the eeprom register.
109		 */
110		eeprom->register_write(eeprom);
111
112		/*
113		 * Kick a pulse.
114		 */
115		eeprom_93cx6_pulse_high(eeprom);
116		eeprom_93cx6_pulse_low(eeprom);
117	}
118
119	eeprom->reg_data_in = 0;
120	eeprom->register_write(eeprom);
121}
122
123static void eeprom_93cx6_read_bits(struct eeprom_93cx6 *eeprom,
124	u16 *data, const u16 count)
125{
126	unsigned int i;
127	u16 buf = 0;
128
129	eeprom->register_read(eeprom);
130
131	/*
132	 * Clear data flags.
133	 */
134	eeprom->reg_data_in = 0;
135	eeprom->reg_data_out = 0;
136	eeprom->drive_data = 0;
137
138	/*
139	 * Start reading all bits.
140	 */
141	for (i = count; i > 0; i--) {
142		eeprom_93cx6_pulse_high(eeprom);
143
144		eeprom->register_read(eeprom);
145
146		/*
147		 * Clear data_in flag.
148		 */
149		eeprom->reg_data_in = 0;
150
151		/*
152		 * Read if the bit has been set.
153		 */
154		if (eeprom->reg_data_out)
155			buf |= (1 << (i - 1));
156
157		eeprom_93cx6_pulse_low(eeprom);
158	}
159
160	*data = buf;
161}
162
163/**
164 * eeprom_93cx6_read - Read a word from eeprom
165 * @eeprom: Pointer to eeprom structure
166 * @word: Word index from where we should start reading
167 * @data: target pointer where the information will have to be stored
168 *
169 * This function will read the eeprom data as host-endian word
170 * into the given data pointer.
171 */
172void eeprom_93cx6_read(struct eeprom_93cx6 *eeprom, const u8 word,
173	u16 *data)
174{
175	u16 command;
176
177	/*
178	 * Initialize the eeprom register
179	 */
180	eeprom_93cx6_startup(eeprom);
181
182	/*
183	 * Select the read opcode and the word to be read.
184	 */
185	command = (PCI_EEPROM_READ_OPCODE << eeprom->width) | word;
186	eeprom_93cx6_write_bits(eeprom, command,
187		PCI_EEPROM_WIDTH_OPCODE + eeprom->width);
188
 
 
 
 
 
189	/*
190	 * Read the requested 16 bits.
191	 */
192	eeprom_93cx6_read_bits(eeprom, data, 16);
193
194	/*
195	 * Cleanup eeprom register.
196	 */
197	eeprom_93cx6_cleanup(eeprom);
198}
199EXPORT_SYMBOL_GPL(eeprom_93cx6_read);
200
201/**
202 * eeprom_93cx6_multiread - Read multiple words from eeprom
203 * @eeprom: Pointer to eeprom structure
204 * @word: Word index from where we should start reading
205 * @data: target pointer where the information will have to be stored
206 * @words: Number of words that should be read.
207 *
208 * This function will read all requested words from the eeprom,
209 * this is done by calling eeprom_93cx6_read() multiple times.
210 * But with the additional change that while the eeprom_93cx6_read
211 * will return host ordered bytes, this method will return little
212 * endian words.
213 */
214void eeprom_93cx6_multiread(struct eeprom_93cx6 *eeprom, const u8 word,
215	__le16 *data, const u16 words)
216{
217	unsigned int i;
218	u16 tmp;
219
220	for (i = 0; i < words; i++) {
221		tmp = 0;
222		eeprom_93cx6_read(eeprom, word + i, &tmp);
223		data[i] = cpu_to_le16(tmp);
224	}
225}
226EXPORT_SYMBOL_GPL(eeprom_93cx6_multiread);
227
228/**
229 * eeprom_93cx6_readb - Read a byte from eeprom
230 * @eeprom: Pointer to eeprom structure
231 * @byte: Byte index from where we should start reading
232 * @data: target pointer where the information will have to be stored
233 *
234 * This function will read a byte of the eeprom data
235 * into the given data pointer.
236 */
237void eeprom_93cx6_readb(struct eeprom_93cx6 *eeprom, const u8 byte,
238	u8 *data)
239{
240	u16 command;
241	u16 tmp;
242
243	/*
244	 * Initialize the eeprom register
245	 */
246	eeprom_93cx6_startup(eeprom);
247
248	/*
249	 * Select the read opcode and the byte to be read.
250	 */
251	command = (PCI_EEPROM_READ_OPCODE << (eeprom->width + 1)) | byte;
252	eeprom_93cx6_write_bits(eeprom, command,
253		PCI_EEPROM_WIDTH_OPCODE + eeprom->width + 1);
 
 
 
 
 
254
255	/*
256	 * Read the requested 8 bits.
257	 */
258	eeprom_93cx6_read_bits(eeprom, &tmp, 8);
259	*data = tmp & 0xff;
260
261	/*
262	 * Cleanup eeprom register.
263	 */
264	eeprom_93cx6_cleanup(eeprom);
265}
266EXPORT_SYMBOL_GPL(eeprom_93cx6_readb);
267
268/**
269 * eeprom_93cx6_multireadb - Read multiple bytes from eeprom
270 * @eeprom: Pointer to eeprom structure
271 * @byte: Index from where we should start reading
272 * @data: target pointer where the information will have to be stored
273 * @bytes: Number of bytes that should be read.
274 *
275 * This function will read all requested bytes from the eeprom,
276 * this is done by calling eeprom_93cx6_readb() multiple times.
277 */
278void eeprom_93cx6_multireadb(struct eeprom_93cx6 *eeprom, const u8 byte,
279	u8 *data, const u16 bytes)
280{
281	unsigned int i;
282
283	for (i = 0; i < bytes; i++)
284		eeprom_93cx6_readb(eeprom, byte + i, &data[i]);
285}
286EXPORT_SYMBOL_GPL(eeprom_93cx6_multireadb);
287
288/**
289 * eeprom_93cx6_wren - set the write enable state
290 * @eeprom: Pointer to eeprom structure
291 * @enable: true to enable writes, otherwise disable writes
292 *
293 * Set the EEPROM write enable state to either allow or deny
294 * writes depending on the @enable value.
295 */
296void eeprom_93cx6_wren(struct eeprom_93cx6 *eeprom, bool enable)
297{
298	u16 command;
299
300	/* start the command */
301	eeprom_93cx6_startup(eeprom);
302
303	/* create command to enable/disable */
304
305	command = enable ? PCI_EEPROM_EWEN_OPCODE : PCI_EEPROM_EWDS_OPCODE;
306	command <<= (eeprom->width - 2);
307
308	eeprom_93cx6_write_bits(eeprom, command,
309				PCI_EEPROM_WIDTH_OPCODE + eeprom->width);
310
311	eeprom_93cx6_cleanup(eeprom);
312}
313EXPORT_SYMBOL_GPL(eeprom_93cx6_wren);
314
315/**
316 * eeprom_93cx6_write - write data to the EEPROM
317 * @eeprom: Pointer to eeprom structure
318 * @addr: Address to write data to.
319 * @data: The data to write to address @addr.
320 *
321 * Write the @data to the specified @addr in the EEPROM and
322 * waiting for the device to finish writing.
323 *
324 * Note, since we do not expect large number of write operations
325 * we delay in between parts of the operation to avoid using excessive
326 * amounts of CPU time busy waiting.
327 */
328void eeprom_93cx6_write(struct eeprom_93cx6 *eeprom, u8 addr, u16 data)
329{
330	int timeout = 100;
331	u16 command;
332
333	/* start the command */
334	eeprom_93cx6_startup(eeprom);
335
336	command = PCI_EEPROM_WRITE_OPCODE << eeprom->width;
337	command |= addr;
338
339	/* send write command */
340	eeprom_93cx6_write_bits(eeprom, command,
341				PCI_EEPROM_WIDTH_OPCODE + eeprom->width);
342
343	/* send data */
344	eeprom_93cx6_write_bits(eeprom, data, 16);
345
346	/* get ready to check for busy */
347	eeprom->drive_data = 0;
348	eeprom->reg_chip_select = 1;
349	eeprom->register_write(eeprom);
350
351	/* wait at-least 250ns to get DO to be the busy signal */
352	usleep_range(1000, 2000);
353
354	/* wait for DO to go high to signify finish */
355
356	while (true) {
357		eeprom->register_read(eeprom);
358
359		if (eeprom->reg_data_out)
360			break;
361
362		usleep_range(1000, 2000);
363
364		if (--timeout <= 0) {
365			printk(KERN_ERR "%s: timeout\n", __func__);
366			break;
367		}
368	}
369
370	eeprom_93cx6_cleanup(eeprom);
371}
372EXPORT_SYMBOL_GPL(eeprom_93cx6_write);
v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Copyright (C) 2004 - 2006 rt2x00 SourceForge Project
  4 * <http://rt2x00.serialmonkey.com>
  5 *
  6 * Module: eeprom_93cx6
  7 * Abstract: EEPROM reader routines for 93cx6 chipsets.
  8 * Supported chipsets: 93c46 & 93c66.
  9 */
 10
 11#include <linux/bits.h>
 12#include <linux/kernel.h>
 13#include <linux/module.h>
 14#include <linux/delay.h>
 15#include <linux/eeprom_93cx6.h>
 16
 17MODULE_AUTHOR("http://rt2x00.serialmonkey.com");
 18MODULE_VERSION("1.0");
 19MODULE_DESCRIPTION("EEPROM 93cx6 chip driver");
 20MODULE_LICENSE("GPL");
 21
 22static inline void eeprom_93cx6_pulse_high(struct eeprom_93cx6 *eeprom)
 23{
 24	eeprom->reg_data_clock = 1;
 25	eeprom->register_write(eeprom);
 26
 27	/*
 28	 * Add a short delay for the pulse to work.
 29	 * According to the specifications the "maximum minimum"
 30	 * time should be 450ns.
 31	 */
 32	ndelay(450);
 33}
 34
 35static inline void eeprom_93cx6_pulse_low(struct eeprom_93cx6 *eeprom)
 36{
 37	eeprom->reg_data_clock = 0;
 38	eeprom->register_write(eeprom);
 39
 40	/*
 41	 * Add a short delay for the pulse to work.
 42	 * According to the specifications the "maximum minimum"
 43	 * time should be 450ns.
 44	 */
 45	ndelay(450);
 46}
 47
 48static void eeprom_93cx6_startup(struct eeprom_93cx6 *eeprom)
 49{
 50	/*
 51	 * Clear all flags, and enable chip select.
 52	 */
 53	eeprom->register_read(eeprom);
 54	eeprom->reg_data_in = 0;
 55	eeprom->reg_data_out = 0;
 56	eeprom->reg_data_clock = 0;
 57	eeprom->reg_chip_select = 1;
 58	eeprom->drive_data = 1;
 59	eeprom->register_write(eeprom);
 60
 61	/*
 62	 * kick a pulse.
 63	 */
 64	eeprom_93cx6_pulse_high(eeprom);
 65	eeprom_93cx6_pulse_low(eeprom);
 66}
 67
 68static void eeprom_93cx6_cleanup(struct eeprom_93cx6 *eeprom)
 69{
 70	/*
 71	 * Clear chip_select and data_in flags.
 72	 */
 73	eeprom->register_read(eeprom);
 74	eeprom->reg_data_in = 0;
 75	eeprom->reg_chip_select = 0;
 76	eeprom->register_write(eeprom);
 77
 78	/*
 79	 * kick a pulse.
 80	 */
 81	eeprom_93cx6_pulse_high(eeprom);
 82	eeprom_93cx6_pulse_low(eeprom);
 83}
 84
 85static void eeprom_93cx6_write_bits(struct eeprom_93cx6 *eeprom,
 86	const u16 data, const u16 count)
 87{
 88	unsigned int i;
 89
 90	eeprom->register_read(eeprom);
 91
 92	/*
 93	 * Clear data flags.
 94	 */
 95	eeprom->reg_data_in = 0;
 96	eeprom->reg_data_out = 0;
 97	eeprom->drive_data = 1;
 98
 99	/*
100	 * Start writing all bits.
101	 */
102	for (i = count; i > 0; i--) {
103		/*
104		 * Check if this bit needs to be set.
105		 */
106		eeprom->reg_data_in = !!(data & BIT(i - 1));
107
108		/*
109		 * Write the bit to the eeprom register.
110		 */
111		eeprom->register_write(eeprom);
112
113		/*
114		 * Kick a pulse.
115		 */
116		eeprom_93cx6_pulse_high(eeprom);
117		eeprom_93cx6_pulse_low(eeprom);
118	}
119
120	eeprom->reg_data_in = 0;
121	eeprom->register_write(eeprom);
122}
123
124static void eeprom_93cx6_read_bits(struct eeprom_93cx6 *eeprom,
125	u16 *data, const u16 count)
126{
127	unsigned int i;
128	u16 buf = 0;
129
130	eeprom->register_read(eeprom);
131
132	/*
133	 * Clear data flags.
134	 */
135	eeprom->reg_data_in = 0;
136	eeprom->reg_data_out = 0;
137	eeprom->drive_data = 0;
138
139	/*
140	 * Start reading all bits.
141	 */
142	for (i = count; i > 0; i--) {
143		eeprom_93cx6_pulse_high(eeprom);
144
145		eeprom->register_read(eeprom);
146
147		/*
148		 * Clear data_in flag.
149		 */
150		eeprom->reg_data_in = 0;
151
152		/*
153		 * Read if the bit has been set.
154		 */
155		if (eeprom->reg_data_out)
156			buf |= BIT(i - 1);
157
158		eeprom_93cx6_pulse_low(eeprom);
159	}
160
161	*data = buf;
162}
163
164/**
165 * eeprom_93cx6_read - Read a word from eeprom
166 * @eeprom: Pointer to eeprom structure
167 * @word: Word index from where we should start reading
168 * @data: target pointer where the information will have to be stored
169 *
170 * This function will read the eeprom data as host-endian word
171 * into the given data pointer.
172 */
173void eeprom_93cx6_read(struct eeprom_93cx6 *eeprom, const u8 word,
174	u16 *data)
175{
176	u16 command;
177
178	/*
179	 * Initialize the eeprom register
180	 */
181	eeprom_93cx6_startup(eeprom);
182
183	/*
184	 * Select the read opcode and the word to be read.
185	 */
186	command = (PCI_EEPROM_READ_OPCODE << eeprom->width) | word;
187	eeprom_93cx6_write_bits(eeprom, command,
188		PCI_EEPROM_WIDTH_OPCODE + eeprom->width);
189
190	if (has_quirk_extra_read_cycle(eeprom)) {
191		eeprom_93cx6_pulse_high(eeprom);
192		eeprom_93cx6_pulse_low(eeprom);
193	}
194
195	/*
196	 * Read the requested 16 bits.
197	 */
198	eeprom_93cx6_read_bits(eeprom, data, 16);
199
200	/*
201	 * Cleanup eeprom register.
202	 */
203	eeprom_93cx6_cleanup(eeprom);
204}
205EXPORT_SYMBOL_GPL(eeprom_93cx6_read);
206
207/**
208 * eeprom_93cx6_multiread - Read multiple words from eeprom
209 * @eeprom: Pointer to eeprom structure
210 * @word: Word index from where we should start reading
211 * @data: target pointer where the information will have to be stored
212 * @words: Number of words that should be read.
213 *
214 * This function will read all requested words from the eeprom,
215 * this is done by calling eeprom_93cx6_read() multiple times.
216 * But with the additional change that while the eeprom_93cx6_read
217 * will return host ordered bytes, this method will return little
218 * endian words.
219 */
220void eeprom_93cx6_multiread(struct eeprom_93cx6 *eeprom, const u8 word,
221	__le16 *data, const u16 words)
222{
223	unsigned int i;
224	u16 tmp;
225
226	for (i = 0; i < words; i++) {
227		tmp = 0;
228		eeprom_93cx6_read(eeprom, word + i, &tmp);
229		data[i] = cpu_to_le16(tmp);
230	}
231}
232EXPORT_SYMBOL_GPL(eeprom_93cx6_multiread);
233
234/**
235 * eeprom_93cx6_readb - Read a byte from eeprom
236 * @eeprom: Pointer to eeprom structure
237 * @byte: Byte index from where we should start reading
238 * @data: target pointer where the information will have to be stored
239 *
240 * This function will read a byte of the eeprom data
241 * into the given data pointer.
242 */
243void eeprom_93cx6_readb(struct eeprom_93cx6 *eeprom, const u8 byte,
244	u8 *data)
245{
246	u16 command;
247	u16 tmp;
248
249	/*
250	 * Initialize the eeprom register
251	 */
252	eeprom_93cx6_startup(eeprom);
253
254	/*
255	 * Select the read opcode and the byte to be read.
256	 */
257	command = (PCI_EEPROM_READ_OPCODE << (eeprom->width + 1)) | byte;
258	eeprom_93cx6_write_bits(eeprom, command,
259		PCI_EEPROM_WIDTH_OPCODE + eeprom->width + 1);
260
261	if (has_quirk_extra_read_cycle(eeprom)) {
262		eeprom_93cx6_pulse_high(eeprom);
263		eeprom_93cx6_pulse_low(eeprom);
264	}
265
266	/*
267	 * Read the requested 8 bits.
268	 */
269	eeprom_93cx6_read_bits(eeprom, &tmp, 8);
270	*data = tmp & 0xff;
271
272	/*
273	 * Cleanup eeprom register.
274	 */
275	eeprom_93cx6_cleanup(eeprom);
276}
277EXPORT_SYMBOL_GPL(eeprom_93cx6_readb);
278
279/**
280 * eeprom_93cx6_multireadb - Read multiple bytes from eeprom
281 * @eeprom: Pointer to eeprom structure
282 * @byte: Index from where we should start reading
283 * @data: target pointer where the information will have to be stored
284 * @bytes: Number of bytes that should be read.
285 *
286 * This function will read all requested bytes from the eeprom,
287 * this is done by calling eeprom_93cx6_readb() multiple times.
288 */
289void eeprom_93cx6_multireadb(struct eeprom_93cx6 *eeprom, const u8 byte,
290	u8 *data, const u16 bytes)
291{
292	unsigned int i;
293
294	for (i = 0; i < bytes; i++)
295		eeprom_93cx6_readb(eeprom, byte + i, &data[i]);
296}
297EXPORT_SYMBOL_GPL(eeprom_93cx6_multireadb);
298
299/**
300 * eeprom_93cx6_wren - set the write enable state
301 * @eeprom: Pointer to eeprom structure
302 * @enable: true to enable writes, otherwise disable writes
303 *
304 * Set the EEPROM write enable state to either allow or deny
305 * writes depending on the @enable value.
306 */
307void eeprom_93cx6_wren(struct eeprom_93cx6 *eeprom, bool enable)
308{
309	u16 command;
310
311	/* start the command */
312	eeprom_93cx6_startup(eeprom);
313
314	/* create command to enable/disable */
315
316	command = enable ? PCI_EEPROM_EWEN_OPCODE : PCI_EEPROM_EWDS_OPCODE;
317	command <<= (eeprom->width - 2);
318
319	eeprom_93cx6_write_bits(eeprom, command,
320				PCI_EEPROM_WIDTH_OPCODE + eeprom->width);
321
322	eeprom_93cx6_cleanup(eeprom);
323}
324EXPORT_SYMBOL_GPL(eeprom_93cx6_wren);
325
326/**
327 * eeprom_93cx6_write - write data to the EEPROM
328 * @eeprom: Pointer to eeprom structure
329 * @addr: Address to write data to.
330 * @data: The data to write to address @addr.
331 *
332 * Write the @data to the specified @addr in the EEPROM and
333 * waiting for the device to finish writing.
334 *
335 * Note, since we do not expect large number of write operations
336 * we delay in between parts of the operation to avoid using excessive
337 * amounts of CPU time busy waiting.
338 */
339void eeprom_93cx6_write(struct eeprom_93cx6 *eeprom, u8 addr, u16 data)
340{
341	int timeout = 100;
342	u16 command;
343
344	/* start the command */
345	eeprom_93cx6_startup(eeprom);
346
347	command = PCI_EEPROM_WRITE_OPCODE << eeprom->width;
348	command |= addr;
349
350	/* send write command */
351	eeprom_93cx6_write_bits(eeprom, command,
352				PCI_EEPROM_WIDTH_OPCODE + eeprom->width);
353
354	/* send data */
355	eeprom_93cx6_write_bits(eeprom, data, 16);
356
357	/* get ready to check for busy */
358	eeprom->drive_data = 0;
359	eeprom->reg_chip_select = 1;
360	eeprom->register_write(eeprom);
361
362	/* wait at-least 250ns to get DO to be the busy signal */
363	usleep_range(1000, 2000);
364
365	/* wait for DO to go high to signify finish */
366
367	while (true) {
368		eeprom->register_read(eeprom);
369
370		if (eeprom->reg_data_out)
371			break;
372
373		usleep_range(1000, 2000);
374
375		if (--timeout <= 0) {
376			printk(KERN_ERR "%s: timeout\n", __func__);
377			break;
378		}
379	}
380
381	eeprom_93cx6_cleanup(eeprom);
382}
383EXPORT_SYMBOL_GPL(eeprom_93cx6_write);