xref: /openbmc/linux/drivers/misc/eeprom/at25.c (revision e51d565ff6bb1cedc10568425511badf0633a212)
1*e51d565fSWolfram Sang /*
2*e51d565fSWolfram Sang  * at25.c -- support most SPI EEPROMs, such as Atmel AT25 models
3*e51d565fSWolfram Sang  *
4*e51d565fSWolfram Sang  * Copyright (C) 2006 David Brownell
5*e51d565fSWolfram Sang  *
6*e51d565fSWolfram Sang  * This program is free software; you can redistribute it and/or modify
7*e51d565fSWolfram Sang  * it under the terms of the GNU General Public License as published by
8*e51d565fSWolfram Sang  * the Free Software Foundation; either version 2 of the License, or
9*e51d565fSWolfram Sang  * (at your option) any later version.
10*e51d565fSWolfram Sang  */
11*e51d565fSWolfram Sang 
12*e51d565fSWolfram Sang #include <linux/kernel.h>
13*e51d565fSWolfram Sang #include <linux/init.h>
14*e51d565fSWolfram Sang #include <linux/module.h>
15*e51d565fSWolfram Sang #include <linux/slab.h>
16*e51d565fSWolfram Sang #include <linux/delay.h>
17*e51d565fSWolfram Sang #include <linux/device.h>
18*e51d565fSWolfram Sang #include <linux/sched.h>
19*e51d565fSWolfram Sang 
20*e51d565fSWolfram Sang #include <linux/spi/spi.h>
21*e51d565fSWolfram Sang #include <linux/spi/eeprom.h>
22*e51d565fSWolfram Sang 
23*e51d565fSWolfram Sang 
24*e51d565fSWolfram Sang /*
25*e51d565fSWolfram Sang  * NOTE: this is an *EEPROM* driver.  The vagaries of product naming
26*e51d565fSWolfram Sang  * mean that some AT25 products are EEPROMs, and others are FLASH.
27*e51d565fSWolfram Sang  * Handle FLASH chips with the drivers/mtd/devices/m25p80.c driver,
28*e51d565fSWolfram Sang  * not this one!
29*e51d565fSWolfram Sang  */
30*e51d565fSWolfram Sang 
31*e51d565fSWolfram Sang struct at25_data {
32*e51d565fSWolfram Sang 	struct spi_device	*spi;
33*e51d565fSWolfram Sang 	struct mutex		lock;
34*e51d565fSWolfram Sang 	struct spi_eeprom	chip;
35*e51d565fSWolfram Sang 	struct bin_attribute	bin;
36*e51d565fSWolfram Sang 	unsigned		addrlen;
37*e51d565fSWolfram Sang };
38*e51d565fSWolfram Sang 
39*e51d565fSWolfram Sang #define	AT25_WREN	0x06		/* latch the write enable */
40*e51d565fSWolfram Sang #define	AT25_WRDI	0x04		/* reset the write enable */
41*e51d565fSWolfram Sang #define	AT25_RDSR	0x05		/* read status register */
42*e51d565fSWolfram Sang #define	AT25_WRSR	0x01		/* write status register */
43*e51d565fSWolfram Sang #define	AT25_READ	0x03		/* read byte(s) */
44*e51d565fSWolfram Sang #define	AT25_WRITE	0x02		/* write byte(s)/sector */
45*e51d565fSWolfram Sang 
46*e51d565fSWolfram Sang #define	AT25_SR_nRDY	0x01		/* nRDY = write-in-progress */
47*e51d565fSWolfram Sang #define	AT25_SR_WEN	0x02		/* write enable (latched) */
48*e51d565fSWolfram Sang #define	AT25_SR_BP0	0x04		/* BP for software writeprotect */
49*e51d565fSWolfram Sang #define	AT25_SR_BP1	0x08
50*e51d565fSWolfram Sang #define	AT25_SR_WPEN	0x80		/* writeprotect enable */
51*e51d565fSWolfram Sang 
52*e51d565fSWolfram Sang 
53*e51d565fSWolfram Sang #define EE_MAXADDRLEN	3		/* 24 bit addresses, up to 2 MBytes */
54*e51d565fSWolfram Sang 
55*e51d565fSWolfram Sang /* Specs often allow 5 msec for a page write, sometimes 20 msec;
56*e51d565fSWolfram Sang  * it's important to recover from write timeouts.
57*e51d565fSWolfram Sang  */
58*e51d565fSWolfram Sang #define	EE_TIMEOUT	25
59*e51d565fSWolfram Sang 
60*e51d565fSWolfram Sang /*-------------------------------------------------------------------------*/
61*e51d565fSWolfram Sang 
62*e51d565fSWolfram Sang #define	io_limit	PAGE_SIZE	/* bytes */
63*e51d565fSWolfram Sang 
64*e51d565fSWolfram Sang static ssize_t
65*e51d565fSWolfram Sang at25_ee_read(
66*e51d565fSWolfram Sang 	struct at25_data	*at25,
67*e51d565fSWolfram Sang 	char			*buf,
68*e51d565fSWolfram Sang 	unsigned		offset,
69*e51d565fSWolfram Sang 	size_t			count
70*e51d565fSWolfram Sang )
71*e51d565fSWolfram Sang {
72*e51d565fSWolfram Sang 	u8			command[EE_MAXADDRLEN + 1];
73*e51d565fSWolfram Sang 	u8			*cp;
74*e51d565fSWolfram Sang 	ssize_t			status;
75*e51d565fSWolfram Sang 	struct spi_transfer	t[2];
76*e51d565fSWolfram Sang 	struct spi_message	m;
77*e51d565fSWolfram Sang 
78*e51d565fSWolfram Sang 	cp = command;
79*e51d565fSWolfram Sang 	*cp++ = AT25_READ;
80*e51d565fSWolfram Sang 
81*e51d565fSWolfram Sang 	/* 8/16/24-bit address is written MSB first */
82*e51d565fSWolfram Sang 	switch (at25->addrlen) {
83*e51d565fSWolfram Sang 	default:	/* case 3 */
84*e51d565fSWolfram Sang 		*cp++ = offset >> 16;
85*e51d565fSWolfram Sang 	case 2:
86*e51d565fSWolfram Sang 		*cp++ = offset >> 8;
87*e51d565fSWolfram Sang 	case 1:
88*e51d565fSWolfram Sang 	case 0:	/* can't happen: for better codegen */
89*e51d565fSWolfram Sang 		*cp++ = offset >> 0;
90*e51d565fSWolfram Sang 	}
91*e51d565fSWolfram Sang 
92*e51d565fSWolfram Sang 	spi_message_init(&m);
93*e51d565fSWolfram Sang 	memset(t, 0, sizeof t);
94*e51d565fSWolfram Sang 
95*e51d565fSWolfram Sang 	t[0].tx_buf = command;
96*e51d565fSWolfram Sang 	t[0].len = at25->addrlen + 1;
97*e51d565fSWolfram Sang 	spi_message_add_tail(&t[0], &m);
98*e51d565fSWolfram Sang 
99*e51d565fSWolfram Sang 	t[1].rx_buf = buf;
100*e51d565fSWolfram Sang 	t[1].len = count;
101*e51d565fSWolfram Sang 	spi_message_add_tail(&t[1], &m);
102*e51d565fSWolfram Sang 
103*e51d565fSWolfram Sang 	mutex_lock(&at25->lock);
104*e51d565fSWolfram Sang 
105*e51d565fSWolfram Sang 	/* Read it all at once.
106*e51d565fSWolfram Sang 	 *
107*e51d565fSWolfram Sang 	 * REVISIT that's potentially a problem with large chips, if
108*e51d565fSWolfram Sang 	 * other devices on the bus need to be accessed regularly or
109*e51d565fSWolfram Sang 	 * this chip is clocked very slowly
110*e51d565fSWolfram Sang 	 */
111*e51d565fSWolfram Sang 	status = spi_sync(at25->spi, &m);
112*e51d565fSWolfram Sang 	dev_dbg(&at25->spi->dev,
113*e51d565fSWolfram Sang 		"read %Zd bytes at %d --> %d\n",
114*e51d565fSWolfram Sang 		count, offset, (int) status);
115*e51d565fSWolfram Sang 
116*e51d565fSWolfram Sang 	mutex_unlock(&at25->lock);
117*e51d565fSWolfram Sang 	return status ? status : count;
118*e51d565fSWolfram Sang }
119*e51d565fSWolfram Sang 
120*e51d565fSWolfram Sang static ssize_t
121*e51d565fSWolfram Sang at25_bin_read(struct kobject *kobj, struct bin_attribute *bin_attr,
122*e51d565fSWolfram Sang 	      char *buf, loff_t off, size_t count)
123*e51d565fSWolfram Sang {
124*e51d565fSWolfram Sang 	struct device		*dev;
125*e51d565fSWolfram Sang 	struct at25_data	*at25;
126*e51d565fSWolfram Sang 
127*e51d565fSWolfram Sang 	dev = container_of(kobj, struct device, kobj);
128*e51d565fSWolfram Sang 	at25 = dev_get_drvdata(dev);
129*e51d565fSWolfram Sang 
130*e51d565fSWolfram Sang 	if (unlikely(off >= at25->bin.size))
131*e51d565fSWolfram Sang 		return 0;
132*e51d565fSWolfram Sang 	if ((off + count) > at25->bin.size)
133*e51d565fSWolfram Sang 		count = at25->bin.size - off;
134*e51d565fSWolfram Sang 	if (unlikely(!count))
135*e51d565fSWolfram Sang 		return count;
136*e51d565fSWolfram Sang 
137*e51d565fSWolfram Sang 	return at25_ee_read(at25, buf, off, count);
138*e51d565fSWolfram Sang }
139*e51d565fSWolfram Sang 
140*e51d565fSWolfram Sang 
141*e51d565fSWolfram Sang static ssize_t
142*e51d565fSWolfram Sang at25_ee_write(struct at25_data *at25, char *buf, loff_t off, size_t count)
143*e51d565fSWolfram Sang {
144*e51d565fSWolfram Sang 	ssize_t			status = 0;
145*e51d565fSWolfram Sang 	unsigned		written = 0;
146*e51d565fSWolfram Sang 	unsigned		buf_size;
147*e51d565fSWolfram Sang 	u8			*bounce;
148*e51d565fSWolfram Sang 
149*e51d565fSWolfram Sang 	/* Temp buffer starts with command and address */
150*e51d565fSWolfram Sang 	buf_size = at25->chip.page_size;
151*e51d565fSWolfram Sang 	if (buf_size > io_limit)
152*e51d565fSWolfram Sang 		buf_size = io_limit;
153*e51d565fSWolfram Sang 	bounce = kmalloc(buf_size + at25->addrlen + 1, GFP_KERNEL);
154*e51d565fSWolfram Sang 	if (!bounce)
155*e51d565fSWolfram Sang 		return -ENOMEM;
156*e51d565fSWolfram Sang 
157*e51d565fSWolfram Sang 	/* For write, rollover is within the page ... so we write at
158*e51d565fSWolfram Sang 	 * most one page, then manually roll over to the next page.
159*e51d565fSWolfram Sang 	 */
160*e51d565fSWolfram Sang 	bounce[0] = AT25_WRITE;
161*e51d565fSWolfram Sang 	mutex_lock(&at25->lock);
162*e51d565fSWolfram Sang 	do {
163*e51d565fSWolfram Sang 		unsigned long	timeout, retries;
164*e51d565fSWolfram Sang 		unsigned	segment;
165*e51d565fSWolfram Sang 		unsigned	offset = (unsigned) off;
166*e51d565fSWolfram Sang 		u8		*cp = bounce + 1;
167*e51d565fSWolfram Sang 
168*e51d565fSWolfram Sang 		*cp = AT25_WREN;
169*e51d565fSWolfram Sang 		status = spi_write(at25->spi, cp, 1);
170*e51d565fSWolfram Sang 		if (status < 0) {
171*e51d565fSWolfram Sang 			dev_dbg(&at25->spi->dev, "WREN --> %d\n",
172*e51d565fSWolfram Sang 					(int) status);
173*e51d565fSWolfram Sang 			break;
174*e51d565fSWolfram Sang 		}
175*e51d565fSWolfram Sang 
176*e51d565fSWolfram Sang 		/* 8/16/24-bit address is written MSB first */
177*e51d565fSWolfram Sang 		switch (at25->addrlen) {
178*e51d565fSWolfram Sang 		default:	/* case 3 */
179*e51d565fSWolfram Sang 			*cp++ = offset >> 16;
180*e51d565fSWolfram Sang 		case 2:
181*e51d565fSWolfram Sang 			*cp++ = offset >> 8;
182*e51d565fSWolfram Sang 		case 1:
183*e51d565fSWolfram Sang 		case 0:	/* can't happen: for better codegen */
184*e51d565fSWolfram Sang 			*cp++ = offset >> 0;
185*e51d565fSWolfram Sang 		}
186*e51d565fSWolfram Sang 
187*e51d565fSWolfram Sang 		/* Write as much of a page as we can */
188*e51d565fSWolfram Sang 		segment = buf_size - (offset % buf_size);
189*e51d565fSWolfram Sang 		if (segment > count)
190*e51d565fSWolfram Sang 			segment = count;
191*e51d565fSWolfram Sang 		memcpy(cp, buf, segment);
192*e51d565fSWolfram Sang 		status = spi_write(at25->spi, bounce,
193*e51d565fSWolfram Sang 				segment + at25->addrlen + 1);
194*e51d565fSWolfram Sang 		dev_dbg(&at25->spi->dev,
195*e51d565fSWolfram Sang 				"write %u bytes at %u --> %d\n",
196*e51d565fSWolfram Sang 				segment, offset, (int) status);
197*e51d565fSWolfram Sang 		if (status < 0)
198*e51d565fSWolfram Sang 			break;
199*e51d565fSWolfram Sang 
200*e51d565fSWolfram Sang 		/* REVISIT this should detect (or prevent) failed writes
201*e51d565fSWolfram Sang 		 * to readonly sections of the EEPROM...
202*e51d565fSWolfram Sang 		 */
203*e51d565fSWolfram Sang 
204*e51d565fSWolfram Sang 		/* Wait for non-busy status */
205*e51d565fSWolfram Sang 		timeout = jiffies + msecs_to_jiffies(EE_TIMEOUT);
206*e51d565fSWolfram Sang 		retries = 0;
207*e51d565fSWolfram Sang 		do {
208*e51d565fSWolfram Sang 			int	sr;
209*e51d565fSWolfram Sang 
210*e51d565fSWolfram Sang 			sr = spi_w8r8(at25->spi, AT25_RDSR);
211*e51d565fSWolfram Sang 			if (sr < 0 || (sr & AT25_SR_nRDY)) {
212*e51d565fSWolfram Sang 				dev_dbg(&at25->spi->dev,
213*e51d565fSWolfram Sang 					"rdsr --> %d (%02x)\n", sr, sr);
214*e51d565fSWolfram Sang 				/* at HZ=100, this is sloooow */
215*e51d565fSWolfram Sang 				msleep(1);
216*e51d565fSWolfram Sang 				continue;
217*e51d565fSWolfram Sang 			}
218*e51d565fSWolfram Sang 			if (!(sr & AT25_SR_nRDY))
219*e51d565fSWolfram Sang 				break;
220*e51d565fSWolfram Sang 		} while (retries++ < 3 || time_before_eq(jiffies, timeout));
221*e51d565fSWolfram Sang 
222*e51d565fSWolfram Sang 		if (time_after(jiffies, timeout)) {
223*e51d565fSWolfram Sang 			dev_err(&at25->spi->dev,
224*e51d565fSWolfram Sang 				"write %d bytes offset %d, "
225*e51d565fSWolfram Sang 				"timeout after %u msecs\n",
226*e51d565fSWolfram Sang 				segment, offset,
227*e51d565fSWolfram Sang 				jiffies_to_msecs(jiffies -
228*e51d565fSWolfram Sang 					(timeout - EE_TIMEOUT)));
229*e51d565fSWolfram Sang 			status = -ETIMEDOUT;
230*e51d565fSWolfram Sang 			break;
231*e51d565fSWolfram Sang 		}
232*e51d565fSWolfram Sang 
233*e51d565fSWolfram Sang 		off += segment;
234*e51d565fSWolfram Sang 		buf += segment;
235*e51d565fSWolfram Sang 		count -= segment;
236*e51d565fSWolfram Sang 		written += segment;
237*e51d565fSWolfram Sang 
238*e51d565fSWolfram Sang 	} while (count > 0);
239*e51d565fSWolfram Sang 
240*e51d565fSWolfram Sang 	mutex_unlock(&at25->lock);
241*e51d565fSWolfram Sang 
242*e51d565fSWolfram Sang 	kfree(bounce);
243*e51d565fSWolfram Sang 	return written ? written : status;
244*e51d565fSWolfram Sang }
245*e51d565fSWolfram Sang 
246*e51d565fSWolfram Sang static ssize_t
247*e51d565fSWolfram Sang at25_bin_write(struct kobject *kobj, struct bin_attribute *bin_attr,
248*e51d565fSWolfram Sang 	       char *buf, loff_t off, size_t count)
249*e51d565fSWolfram Sang {
250*e51d565fSWolfram Sang 	struct device		*dev;
251*e51d565fSWolfram Sang 	struct at25_data	*at25;
252*e51d565fSWolfram Sang 
253*e51d565fSWolfram Sang 	dev = container_of(kobj, struct device, kobj);
254*e51d565fSWolfram Sang 	at25 = dev_get_drvdata(dev);
255*e51d565fSWolfram Sang 
256*e51d565fSWolfram Sang 	if (unlikely(off >= at25->bin.size))
257*e51d565fSWolfram Sang 		return -EFBIG;
258*e51d565fSWolfram Sang 	if ((off + count) > at25->bin.size)
259*e51d565fSWolfram Sang 		count = at25->bin.size - off;
260*e51d565fSWolfram Sang 	if (unlikely(!count))
261*e51d565fSWolfram Sang 		return count;
262*e51d565fSWolfram Sang 
263*e51d565fSWolfram Sang 	return at25_ee_write(at25, buf, off, count);
264*e51d565fSWolfram Sang }
265*e51d565fSWolfram Sang 
266*e51d565fSWolfram Sang /*-------------------------------------------------------------------------*/
267*e51d565fSWolfram Sang 
268*e51d565fSWolfram Sang static int at25_probe(struct spi_device *spi)
269*e51d565fSWolfram Sang {
270*e51d565fSWolfram Sang 	struct at25_data	*at25 = NULL;
271*e51d565fSWolfram Sang 	const struct spi_eeprom *chip;
272*e51d565fSWolfram Sang 	int			err;
273*e51d565fSWolfram Sang 	int			sr;
274*e51d565fSWolfram Sang 	int			addrlen;
275*e51d565fSWolfram Sang 
276*e51d565fSWolfram Sang 	/* Chip description */
277*e51d565fSWolfram Sang 	chip = spi->dev.platform_data;
278*e51d565fSWolfram Sang 	if (!chip) {
279*e51d565fSWolfram Sang 		dev_dbg(&spi->dev, "no chip description\n");
280*e51d565fSWolfram Sang 		err = -ENODEV;
281*e51d565fSWolfram Sang 		goto fail;
282*e51d565fSWolfram Sang 	}
283*e51d565fSWolfram Sang 
284*e51d565fSWolfram Sang 	/* For now we only support 8/16/24 bit addressing */
285*e51d565fSWolfram Sang 	if (chip->flags & EE_ADDR1)
286*e51d565fSWolfram Sang 		addrlen = 1;
287*e51d565fSWolfram Sang 	else if (chip->flags & EE_ADDR2)
288*e51d565fSWolfram Sang 		addrlen = 2;
289*e51d565fSWolfram Sang 	else if (chip->flags & EE_ADDR3)
290*e51d565fSWolfram Sang 		addrlen = 3;
291*e51d565fSWolfram Sang 	else {
292*e51d565fSWolfram Sang 		dev_dbg(&spi->dev, "unsupported address type\n");
293*e51d565fSWolfram Sang 		err = -EINVAL;
294*e51d565fSWolfram Sang 		goto fail;
295*e51d565fSWolfram Sang 	}
296*e51d565fSWolfram Sang 
297*e51d565fSWolfram Sang 	/* Ping the chip ... the status register is pretty portable,
298*e51d565fSWolfram Sang 	 * unlike probing manufacturer IDs.  We do expect that system
299*e51d565fSWolfram Sang 	 * firmware didn't write it in the past few milliseconds!
300*e51d565fSWolfram Sang 	 */
301*e51d565fSWolfram Sang 	sr = spi_w8r8(spi, AT25_RDSR);
302*e51d565fSWolfram Sang 	if (sr < 0 || sr & AT25_SR_nRDY) {
303*e51d565fSWolfram Sang 		dev_dbg(&spi->dev, "rdsr --> %d (%02x)\n", sr, sr);
304*e51d565fSWolfram Sang 		err = -ENXIO;
305*e51d565fSWolfram Sang 		goto fail;
306*e51d565fSWolfram Sang 	}
307*e51d565fSWolfram Sang 
308*e51d565fSWolfram Sang 	if (!(at25 = kzalloc(sizeof *at25, GFP_KERNEL))) {
309*e51d565fSWolfram Sang 		err = -ENOMEM;
310*e51d565fSWolfram Sang 		goto fail;
311*e51d565fSWolfram Sang 	}
312*e51d565fSWolfram Sang 
313*e51d565fSWolfram Sang 	mutex_init(&at25->lock);
314*e51d565fSWolfram Sang 	at25->chip = *chip;
315*e51d565fSWolfram Sang 	at25->spi = spi_dev_get(spi);
316*e51d565fSWolfram Sang 	dev_set_drvdata(&spi->dev, at25);
317*e51d565fSWolfram Sang 	at25->addrlen = addrlen;
318*e51d565fSWolfram Sang 
319*e51d565fSWolfram Sang 	/* Export the EEPROM bytes through sysfs, since that's convenient.
320*e51d565fSWolfram Sang 	 * Default to root-only access to the data; EEPROMs often hold data
321*e51d565fSWolfram Sang 	 * that's sensitive for read and/or write, like ethernet addresses,
322*e51d565fSWolfram Sang 	 * security codes, board-specific manufacturing calibrations, etc.
323*e51d565fSWolfram Sang 	 */
324*e51d565fSWolfram Sang 	at25->bin.attr.name = "eeprom";
325*e51d565fSWolfram Sang 	at25->bin.attr.mode = S_IRUSR;
326*e51d565fSWolfram Sang 	at25->bin.read = at25_bin_read;
327*e51d565fSWolfram Sang 
328*e51d565fSWolfram Sang 	at25->bin.size = at25->chip.byte_len;
329*e51d565fSWolfram Sang 	if (!(chip->flags & EE_READONLY)) {
330*e51d565fSWolfram Sang 		at25->bin.write = at25_bin_write;
331*e51d565fSWolfram Sang 		at25->bin.attr.mode |= S_IWUSR;
332*e51d565fSWolfram Sang 	}
333*e51d565fSWolfram Sang 
334*e51d565fSWolfram Sang 	err = sysfs_create_bin_file(&spi->dev.kobj, &at25->bin);
335*e51d565fSWolfram Sang 	if (err)
336*e51d565fSWolfram Sang 		goto fail;
337*e51d565fSWolfram Sang 
338*e51d565fSWolfram Sang 	dev_info(&spi->dev, "%Zd %s %s eeprom%s, pagesize %u\n",
339*e51d565fSWolfram Sang 		(at25->bin.size < 1024)
340*e51d565fSWolfram Sang 			? at25->bin.size
341*e51d565fSWolfram Sang 			: (at25->bin.size / 1024),
342*e51d565fSWolfram Sang 		(at25->bin.size < 1024) ? "Byte" : "KByte",
343*e51d565fSWolfram Sang 		at25->chip.name,
344*e51d565fSWolfram Sang 		(chip->flags & EE_READONLY) ? " (readonly)" : "",
345*e51d565fSWolfram Sang 		at25->chip.page_size);
346*e51d565fSWolfram Sang 	return 0;
347*e51d565fSWolfram Sang fail:
348*e51d565fSWolfram Sang 	dev_dbg(&spi->dev, "probe err %d\n", err);
349*e51d565fSWolfram Sang 	kfree(at25);
350*e51d565fSWolfram Sang 	return err;
351*e51d565fSWolfram Sang }
352*e51d565fSWolfram Sang 
353*e51d565fSWolfram Sang static int __devexit at25_remove(struct spi_device *spi)
354*e51d565fSWolfram Sang {
355*e51d565fSWolfram Sang 	struct at25_data	*at25;
356*e51d565fSWolfram Sang 
357*e51d565fSWolfram Sang 	at25 = dev_get_drvdata(&spi->dev);
358*e51d565fSWolfram Sang 	sysfs_remove_bin_file(&spi->dev.kobj, &at25->bin);
359*e51d565fSWolfram Sang 	kfree(at25);
360*e51d565fSWolfram Sang 	return 0;
361*e51d565fSWolfram Sang }
362*e51d565fSWolfram Sang 
363*e51d565fSWolfram Sang /*-------------------------------------------------------------------------*/
364*e51d565fSWolfram Sang 
365*e51d565fSWolfram Sang static struct spi_driver at25_driver = {
366*e51d565fSWolfram Sang 	.driver = {
367*e51d565fSWolfram Sang 		.name		= "at25",
368*e51d565fSWolfram Sang 		.owner		= THIS_MODULE,
369*e51d565fSWolfram Sang 	},
370*e51d565fSWolfram Sang 	.probe		= at25_probe,
371*e51d565fSWolfram Sang 	.remove		= __devexit_p(at25_remove),
372*e51d565fSWolfram Sang };
373*e51d565fSWolfram Sang 
374*e51d565fSWolfram Sang static int __init at25_init(void)
375*e51d565fSWolfram Sang {
376*e51d565fSWolfram Sang 	return spi_register_driver(&at25_driver);
377*e51d565fSWolfram Sang }
378*e51d565fSWolfram Sang module_init(at25_init);
379*e51d565fSWolfram Sang 
380*e51d565fSWolfram Sang static void __exit at25_exit(void)
381*e51d565fSWolfram Sang {
382*e51d565fSWolfram Sang 	spi_unregister_driver(&at25_driver);
383*e51d565fSWolfram Sang }
384*e51d565fSWolfram Sang module_exit(at25_exit);
385*e51d565fSWolfram Sang 
386*e51d565fSWolfram Sang MODULE_DESCRIPTION("Driver for most SPI EEPROMs");
387*e51d565fSWolfram Sang MODULE_AUTHOR("David Brownell");
388*e51d565fSWolfram Sang MODULE_LICENSE("GPL");
389*e51d565fSWolfram Sang 
390