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1/*
2 * Driver for 93xx46 EEPROMs
3 *
4 * (C) 2011 DENX Software Engineering, Anatolij Gustschin <agust@denx.de>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#include <linux/delay.h>
12#include <linux/device.h>
13#include <linux/kernel.h>
14#include <linux/init.h>
15#include <linux/module.h>
16#include <linux/mutex.h>
17#include <linux/slab.h>
18#include <linux/spi/spi.h>
19#include <linux/sysfs.h>
20#include <linux/eeprom_93xx46.h>
21
22#define OP_START 0x4
23#define OP_WRITE (OP_START | 0x1)
24#define OP_READ (OP_START | 0x2)
25#define ADDR_EWDS 0x00
26#define ADDR_ERAL 0x20
27#define ADDR_EWEN 0x30
28
29struct eeprom_93xx46_dev {
30 struct spi_device *spi;
31 struct eeprom_93xx46_platform_data *pdata;
32 struct bin_attribute bin;
33 struct mutex lock;
34 int addrlen;
35};
36
37static ssize_t
38eeprom_93xx46_bin_read(struct file *filp, struct kobject *kobj,
39 struct bin_attribute *bin_attr,
40 char *buf, loff_t off, size_t count)
41{
42 struct eeprom_93xx46_dev *edev;
43 struct device *dev;
44 struct spi_message m;
45 struct spi_transfer t[2];
46 int bits, ret;
47 u16 cmd_addr;
48
49 dev = container_of(kobj, struct device, kobj);
50 edev = dev_get_drvdata(dev);
51
52 if (unlikely(off >= edev->bin.size))
53 return 0;
54 if ((off + count) > edev->bin.size)
55 count = edev->bin.size - off;
56 if (unlikely(!count))
57 return count;
58
59 cmd_addr = OP_READ << edev->addrlen;
60
61 if (edev->addrlen == 7) {
62 cmd_addr |= off & 0x7f;
63 bits = 10;
64 } else {
65 cmd_addr |= off & 0x3f;
66 bits = 9;
67 }
68
69 dev_dbg(&edev->spi->dev, "read cmd 0x%x, %d Hz\n",
70 cmd_addr, edev->spi->max_speed_hz);
71
72 spi_message_init(&m);
73 memset(t, 0, sizeof(t));
74
75 t[0].tx_buf = (char *)&cmd_addr;
76 t[0].len = 2;
77 t[0].bits_per_word = bits;
78 spi_message_add_tail(&t[0], &m);
79
80 t[1].rx_buf = buf;
81 t[1].len = count;
82 t[1].bits_per_word = 8;
83 spi_message_add_tail(&t[1], &m);
84
85 mutex_lock(&edev->lock);
86
87 if (edev->pdata->prepare)
88 edev->pdata->prepare(edev);
89
90 ret = spi_sync(edev->spi, &m);
91 /* have to wait at least Tcsl ns */
92 ndelay(250);
93 if (ret) {
94 dev_err(&edev->spi->dev, "read %zu bytes at %d: err. %d\n",
95 count, (int)off, ret);
96 }
97
98 if (edev->pdata->finish)
99 edev->pdata->finish(edev);
100
101 mutex_unlock(&edev->lock);
102 return ret ? : count;
103}
104
105static int eeprom_93xx46_ew(struct eeprom_93xx46_dev *edev, int is_on)
106{
107 struct spi_message m;
108 struct spi_transfer t;
109 int bits, ret;
110 u16 cmd_addr;
111
112 cmd_addr = OP_START << edev->addrlen;
113 if (edev->addrlen == 7) {
114 cmd_addr |= (is_on ? ADDR_EWEN : ADDR_EWDS) << 1;
115 bits = 10;
116 } else {
117 cmd_addr |= (is_on ? ADDR_EWEN : ADDR_EWDS);
118 bits = 9;
119 }
120
121 dev_dbg(&edev->spi->dev, "ew cmd 0x%04x\n", cmd_addr);
122
123 spi_message_init(&m);
124 memset(&t, 0, sizeof(t));
125
126 t.tx_buf = &cmd_addr;
127 t.len = 2;
128 t.bits_per_word = bits;
129 spi_message_add_tail(&t, &m);
130
131 mutex_lock(&edev->lock);
132
133 if (edev->pdata->prepare)
134 edev->pdata->prepare(edev);
135
136 ret = spi_sync(edev->spi, &m);
137 /* have to wait at least Tcsl ns */
138 ndelay(250);
139 if (ret)
140 dev_err(&edev->spi->dev, "erase/write %sable error %d\n",
141 is_on ? "en" : "dis", ret);
142
143 if (edev->pdata->finish)
144 edev->pdata->finish(edev);
145
146 mutex_unlock(&edev->lock);
147 return ret;
148}
149
150static ssize_t
151eeprom_93xx46_write_word(struct eeprom_93xx46_dev *edev,
152 const char *buf, unsigned off)
153{
154 struct spi_message m;
155 struct spi_transfer t[2];
156 int bits, data_len, ret;
157 u16 cmd_addr;
158
159 cmd_addr = OP_WRITE << edev->addrlen;
160
161 if (edev->addrlen == 7) {
162 cmd_addr |= off & 0x7f;
163 bits = 10;
164 data_len = 1;
165 } else {
166 cmd_addr |= off & 0x3f;
167 bits = 9;
168 data_len = 2;
169 }
170
171 dev_dbg(&edev->spi->dev, "write cmd 0x%x\n", cmd_addr);
172
173 spi_message_init(&m);
174 memset(t, 0, sizeof(t));
175
176 t[0].tx_buf = (char *)&cmd_addr;
177 t[0].len = 2;
178 t[0].bits_per_word = bits;
179 spi_message_add_tail(&t[0], &m);
180
181 t[1].tx_buf = buf;
182 t[1].len = data_len;
183 t[1].bits_per_word = 8;
184 spi_message_add_tail(&t[1], &m);
185
186 ret = spi_sync(edev->spi, &m);
187 /* have to wait program cycle time Twc ms */
188 mdelay(6);
189 return ret;
190}
191
192static ssize_t
193eeprom_93xx46_bin_write(struct file *filp, struct kobject *kobj,
194 struct bin_attribute *bin_attr,
195 char *buf, loff_t off, size_t count)
196{
197 struct eeprom_93xx46_dev *edev;
198 struct device *dev;
199 int i, ret, step = 1;
200
201 dev = container_of(kobj, struct device, kobj);
202 edev = dev_get_drvdata(dev);
203
204 if (unlikely(off >= edev->bin.size))
205 return 0;
206 if ((off + count) > edev->bin.size)
207 count = edev->bin.size - off;
208 if (unlikely(!count))
209 return count;
210
211 /* only write even number of bytes on 16-bit devices */
212 if (edev->addrlen == 6) {
213 step = 2;
214 count &= ~1;
215 }
216
217 /* erase/write enable */
218 ret = eeprom_93xx46_ew(edev, 1);
219 if (ret)
220 return ret;
221
222 mutex_lock(&edev->lock);
223
224 if (edev->pdata->prepare)
225 edev->pdata->prepare(edev);
226
227 for (i = 0; i < count; i += step) {
228 ret = eeprom_93xx46_write_word(edev, &buf[i], off + i);
229 if (ret) {
230 dev_err(&edev->spi->dev, "write failed at %d: %d\n",
231 (int)off + i, ret);
232 break;
233 }
234 }
235
236 if (edev->pdata->finish)
237 edev->pdata->finish(edev);
238
239 mutex_unlock(&edev->lock);
240
241 /* erase/write disable */
242 eeprom_93xx46_ew(edev, 0);
243 return ret ? : count;
244}
245
246static int eeprom_93xx46_eral(struct eeprom_93xx46_dev *edev)
247{
248 struct eeprom_93xx46_platform_data *pd = edev->pdata;
249 struct spi_message m;
250 struct spi_transfer t;
251 int bits, ret;
252 u16 cmd_addr;
253
254 cmd_addr = OP_START << edev->addrlen;
255 if (edev->addrlen == 7) {
256 cmd_addr |= ADDR_ERAL << 1;
257 bits = 10;
258 } else {
259 cmd_addr |= ADDR_ERAL;
260 bits = 9;
261 }
262
263 spi_message_init(&m);
264 memset(&t, 0, sizeof(t));
265
266 t.tx_buf = &cmd_addr;
267 t.len = 2;
268 t.bits_per_word = bits;
269 spi_message_add_tail(&t, &m);
270
271 mutex_lock(&edev->lock);
272
273 if (edev->pdata->prepare)
274 edev->pdata->prepare(edev);
275
276 ret = spi_sync(edev->spi, &m);
277 if (ret)
278 dev_err(&edev->spi->dev, "erase error %d\n", ret);
279 /* have to wait erase cycle time Tec ms */
280 mdelay(6);
281
282 if (pd->finish)
283 pd->finish(edev);
284
285 mutex_unlock(&edev->lock);
286 return ret;
287}
288
289static ssize_t eeprom_93xx46_store_erase(struct device *dev,
290 struct device_attribute *attr,
291 const char *buf, size_t count)
292{
293 struct eeprom_93xx46_dev *edev = dev_get_drvdata(dev);
294 int erase = 0, ret;
295
296 sscanf(buf, "%d", &erase);
297 if (erase) {
298 ret = eeprom_93xx46_ew(edev, 1);
299 if (ret)
300 return ret;
301 ret = eeprom_93xx46_eral(edev);
302 if (ret)
303 return ret;
304 ret = eeprom_93xx46_ew(edev, 0);
305 if (ret)
306 return ret;
307 }
308 return count;
309}
310static DEVICE_ATTR(erase, S_IWUSR, NULL, eeprom_93xx46_store_erase);
311
312static int __devinit eeprom_93xx46_probe(struct spi_device *spi)
313{
314 struct eeprom_93xx46_platform_data *pd;
315 struct eeprom_93xx46_dev *edev;
316 int err;
317
318 pd = spi->dev.platform_data;
319 if (!pd) {
320 dev_err(&spi->dev, "missing platform data\n");
321 return -ENODEV;
322 }
323
324 edev = kzalloc(sizeof(*edev), GFP_KERNEL);
325 if (!edev)
326 return -ENOMEM;
327
328 if (pd->flags & EE_ADDR8)
329 edev->addrlen = 7;
330 else if (pd->flags & EE_ADDR16)
331 edev->addrlen = 6;
332 else {
333 dev_err(&spi->dev, "unspecified address type\n");
334 err = -EINVAL;
335 goto fail;
336 }
337
338 mutex_init(&edev->lock);
339
340 edev->spi = spi_dev_get(spi);
341 edev->pdata = pd;
342
343 sysfs_bin_attr_init(&edev->bin);
344 edev->bin.attr.name = "eeprom";
345 edev->bin.attr.mode = S_IRUSR;
346 edev->bin.read = eeprom_93xx46_bin_read;
347 edev->bin.size = 128;
348 if (!(pd->flags & EE_READONLY)) {
349 edev->bin.write = eeprom_93xx46_bin_write;
350 edev->bin.attr.mode |= S_IWUSR;
351 }
352
353 err = sysfs_create_bin_file(&spi->dev.kobj, &edev->bin);
354 if (err)
355 goto fail;
356
357 dev_info(&spi->dev, "%d-bit eeprom %s\n",
358 (pd->flags & EE_ADDR8) ? 8 : 16,
359 (pd->flags & EE_READONLY) ? "(readonly)" : "");
360
361 if (!(pd->flags & EE_READONLY)) {
362 if (device_create_file(&spi->dev, &dev_attr_erase))
363 dev_err(&spi->dev, "can't create erase interface\n");
364 }
365
366 dev_set_drvdata(&spi->dev, edev);
367 return 0;
368fail:
369 kfree(edev);
370 return err;
371}
372
373static int __devexit eeprom_93xx46_remove(struct spi_device *spi)
374{
375 struct eeprom_93xx46_dev *edev = dev_get_drvdata(&spi->dev);
376
377 if (!(edev->pdata->flags & EE_READONLY))
378 device_remove_file(&spi->dev, &dev_attr_erase);
379
380 sysfs_remove_bin_file(&spi->dev.kobj, &edev->bin);
381 dev_set_drvdata(&spi->dev, NULL);
382 kfree(edev);
383 return 0;
384}
385
386static struct spi_driver eeprom_93xx46_driver = {
387 .driver = {
388 .name = "93xx46",
389 .owner = THIS_MODULE,
390 },
391 .probe = eeprom_93xx46_probe,
392 .remove = __devexit_p(eeprom_93xx46_remove),
393};
394
395static int __init eeprom_93xx46_init(void)
396{
397 return spi_register_driver(&eeprom_93xx46_driver);
398}
399module_init(eeprom_93xx46_init);
400
401static void __exit eeprom_93xx46_exit(void)
402{
403 spi_unregister_driver(&eeprom_93xx46_driver);
404}
405module_exit(eeprom_93xx46_exit);
406
407MODULE_LICENSE("GPL");
408MODULE_DESCRIPTION("Driver for 93xx46 EEPROMs");
409MODULE_AUTHOR("Anatolij Gustschin <agust@denx.de>");
410MODULE_ALIAS("spi:93xx46");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Driver for 93xx46 EEPROMs
4 *
5 * (C) 2011 DENX Software Engineering, Anatolij Gustschin <agust@denx.de>
6 */
7
8#include <linux/delay.h>
9#include <linux/device.h>
10#include <linux/gpio/consumer.h>
11#include <linux/kernel.h>
12#include <linux/log2.h>
13#include <linux/module.h>
14#include <linux/mutex.h>
15#include <linux/of.h>
16#include <linux/of_device.h>
17#include <linux/slab.h>
18#include <linux/spi/spi.h>
19#include <linux/nvmem-provider.h>
20#include <linux/eeprom_93xx46.h>
21
22#define OP_START 0x4
23#define OP_WRITE (OP_START | 0x1)
24#define OP_READ (OP_START | 0x2)
25#define ADDR_EWDS 0x00
26#define ADDR_ERAL 0x20
27#define ADDR_EWEN 0x30
28
29struct eeprom_93xx46_devtype_data {
30 unsigned int quirks;
31 unsigned char flags;
32};
33
34static const struct eeprom_93xx46_devtype_data at93c46_data = {
35 .flags = EE_SIZE1K,
36};
37
38static const struct eeprom_93xx46_devtype_data at93c56_data = {
39 .flags = EE_SIZE2K,
40};
41
42static const struct eeprom_93xx46_devtype_data at93c66_data = {
43 .flags = EE_SIZE4K,
44};
45
46static const struct eeprom_93xx46_devtype_data atmel_at93c46d_data = {
47 .flags = EE_SIZE1K,
48 .quirks = EEPROM_93XX46_QUIRK_SINGLE_WORD_READ |
49 EEPROM_93XX46_QUIRK_INSTRUCTION_LENGTH,
50};
51
52static const struct eeprom_93xx46_devtype_data microchip_93lc46b_data = {
53 .flags = EE_SIZE1K,
54 .quirks = EEPROM_93XX46_QUIRK_EXTRA_READ_CYCLE,
55};
56
57struct eeprom_93xx46_dev {
58 struct spi_device *spi;
59 struct eeprom_93xx46_platform_data *pdata;
60 struct mutex lock;
61 struct nvmem_config nvmem_config;
62 struct nvmem_device *nvmem;
63 int addrlen;
64 int size;
65};
66
67static inline bool has_quirk_single_word_read(struct eeprom_93xx46_dev *edev)
68{
69 return edev->pdata->quirks & EEPROM_93XX46_QUIRK_SINGLE_WORD_READ;
70}
71
72static inline bool has_quirk_instruction_length(struct eeprom_93xx46_dev *edev)
73{
74 return edev->pdata->quirks & EEPROM_93XX46_QUIRK_INSTRUCTION_LENGTH;
75}
76
77static inline bool has_quirk_extra_read_cycle(struct eeprom_93xx46_dev *edev)
78{
79 return edev->pdata->quirks & EEPROM_93XX46_QUIRK_EXTRA_READ_CYCLE;
80}
81
82static int eeprom_93xx46_read(void *priv, unsigned int off,
83 void *val, size_t count)
84{
85 struct eeprom_93xx46_dev *edev = priv;
86 char *buf = val;
87 int err = 0;
88 int bits;
89
90 if (unlikely(off >= edev->size))
91 return 0;
92 if ((off + count) > edev->size)
93 count = edev->size - off;
94 if (unlikely(!count))
95 return count;
96
97 mutex_lock(&edev->lock);
98
99 if (edev->pdata->prepare)
100 edev->pdata->prepare(edev);
101
102 /* The opcode in front of the address is three bits. */
103 bits = edev->addrlen + 3;
104
105 while (count) {
106 struct spi_message m;
107 struct spi_transfer t[2] = { { 0 } };
108 u16 cmd_addr = OP_READ << edev->addrlen;
109 size_t nbytes = count;
110
111 if (edev->pdata->flags & EE_ADDR8) {
112 cmd_addr |= off;
113 if (has_quirk_single_word_read(edev))
114 nbytes = 1;
115 } else {
116 cmd_addr |= (off >> 1);
117 if (has_quirk_single_word_read(edev))
118 nbytes = 2;
119 }
120
121 dev_dbg(&edev->spi->dev, "read cmd 0x%x, %d Hz\n",
122 cmd_addr, edev->spi->max_speed_hz);
123
124 if (has_quirk_extra_read_cycle(edev)) {
125 cmd_addr <<= 1;
126 bits += 1;
127 }
128
129 spi_message_init(&m);
130
131 t[0].tx_buf = (char *)&cmd_addr;
132 t[0].len = 2;
133 t[0].bits_per_word = bits;
134 spi_message_add_tail(&t[0], &m);
135
136 t[1].rx_buf = buf;
137 t[1].len = count;
138 t[1].bits_per_word = 8;
139 spi_message_add_tail(&t[1], &m);
140
141 err = spi_sync(edev->spi, &m);
142 /* have to wait at least Tcsl ns */
143 ndelay(250);
144
145 if (err) {
146 dev_err(&edev->spi->dev, "read %zu bytes at %d: err. %d\n",
147 nbytes, (int)off, err);
148 break;
149 }
150
151 buf += nbytes;
152 off += nbytes;
153 count -= nbytes;
154 }
155
156 if (edev->pdata->finish)
157 edev->pdata->finish(edev);
158
159 mutex_unlock(&edev->lock);
160
161 return err;
162}
163
164static int eeprom_93xx46_ew(struct eeprom_93xx46_dev *edev, int is_on)
165{
166 struct spi_message m;
167 struct spi_transfer t;
168 int bits, ret;
169 u16 cmd_addr;
170
171 /* The opcode in front of the address is three bits. */
172 bits = edev->addrlen + 3;
173
174 cmd_addr = OP_START << edev->addrlen;
175 if (edev->pdata->flags & EE_ADDR8)
176 cmd_addr |= (is_on ? ADDR_EWEN : ADDR_EWDS) << 1;
177 else
178 cmd_addr |= (is_on ? ADDR_EWEN : ADDR_EWDS);
179
180 if (has_quirk_instruction_length(edev)) {
181 cmd_addr <<= 2;
182 bits += 2;
183 }
184
185 dev_dbg(&edev->spi->dev, "ew%s cmd 0x%04x, %d bits\n",
186 is_on ? "en" : "ds", cmd_addr, bits);
187
188 spi_message_init(&m);
189 memset(&t, 0, sizeof(t));
190
191 t.tx_buf = &cmd_addr;
192 t.len = 2;
193 t.bits_per_word = bits;
194 spi_message_add_tail(&t, &m);
195
196 mutex_lock(&edev->lock);
197
198 if (edev->pdata->prepare)
199 edev->pdata->prepare(edev);
200
201 ret = spi_sync(edev->spi, &m);
202 /* have to wait at least Tcsl ns */
203 ndelay(250);
204 if (ret)
205 dev_err(&edev->spi->dev, "erase/write %sable error %d\n",
206 is_on ? "en" : "dis", ret);
207
208 if (edev->pdata->finish)
209 edev->pdata->finish(edev);
210
211 mutex_unlock(&edev->lock);
212 return ret;
213}
214
215static ssize_t
216eeprom_93xx46_write_word(struct eeprom_93xx46_dev *edev,
217 const char *buf, unsigned off)
218{
219 struct spi_message m;
220 struct spi_transfer t[2];
221 int bits, data_len, ret;
222 u16 cmd_addr;
223
224 if (unlikely(off >= edev->size))
225 return -EINVAL;
226
227 /* The opcode in front of the address is three bits. */
228 bits = edev->addrlen + 3;
229
230 cmd_addr = OP_WRITE << edev->addrlen;
231
232 if (edev->pdata->flags & EE_ADDR8) {
233 cmd_addr |= off;
234 data_len = 1;
235 } else {
236 cmd_addr |= (off >> 1);
237 data_len = 2;
238 }
239
240 dev_dbg(&edev->spi->dev, "write cmd 0x%x\n", cmd_addr);
241
242 spi_message_init(&m);
243 memset(t, 0, sizeof(t));
244
245 t[0].tx_buf = (char *)&cmd_addr;
246 t[0].len = 2;
247 t[0].bits_per_word = bits;
248 spi_message_add_tail(&t[0], &m);
249
250 t[1].tx_buf = buf;
251 t[1].len = data_len;
252 t[1].bits_per_word = 8;
253 spi_message_add_tail(&t[1], &m);
254
255 ret = spi_sync(edev->spi, &m);
256 /* have to wait program cycle time Twc ms */
257 mdelay(6);
258 return ret;
259}
260
261static int eeprom_93xx46_write(void *priv, unsigned int off,
262 void *val, size_t count)
263{
264 struct eeprom_93xx46_dev *edev = priv;
265 char *buf = val;
266 int i, ret, step = 1;
267
268 if (unlikely(off >= edev->size))
269 return -EFBIG;
270 if ((off + count) > edev->size)
271 count = edev->size - off;
272 if (unlikely(!count))
273 return count;
274
275 /* only write even number of bytes on 16-bit devices */
276 if (edev->pdata->flags & EE_ADDR16) {
277 step = 2;
278 count &= ~1;
279 }
280
281 /* erase/write enable */
282 ret = eeprom_93xx46_ew(edev, 1);
283 if (ret)
284 return ret;
285
286 mutex_lock(&edev->lock);
287
288 if (edev->pdata->prepare)
289 edev->pdata->prepare(edev);
290
291 for (i = 0; i < count; i += step) {
292 ret = eeprom_93xx46_write_word(edev, &buf[i], off + i);
293 if (ret) {
294 dev_err(&edev->spi->dev, "write failed at %d: %d\n",
295 (int)off + i, ret);
296 break;
297 }
298 }
299
300 if (edev->pdata->finish)
301 edev->pdata->finish(edev);
302
303 mutex_unlock(&edev->lock);
304
305 /* erase/write disable */
306 eeprom_93xx46_ew(edev, 0);
307 return ret;
308}
309
310static int eeprom_93xx46_eral(struct eeprom_93xx46_dev *edev)
311{
312 struct eeprom_93xx46_platform_data *pd = edev->pdata;
313 struct spi_message m;
314 struct spi_transfer t;
315 int bits, ret;
316 u16 cmd_addr;
317
318 /* The opcode in front of the address is three bits. */
319 bits = edev->addrlen + 3;
320
321 cmd_addr = OP_START << edev->addrlen;
322 if (edev->pdata->flags & EE_ADDR8)
323 cmd_addr |= ADDR_ERAL << 1;
324 else
325 cmd_addr |= ADDR_ERAL;
326
327 if (has_quirk_instruction_length(edev)) {
328 cmd_addr <<= 2;
329 bits += 2;
330 }
331
332 dev_dbg(&edev->spi->dev, "eral cmd 0x%04x, %d bits\n", cmd_addr, bits);
333
334 spi_message_init(&m);
335 memset(&t, 0, sizeof(t));
336
337 t.tx_buf = &cmd_addr;
338 t.len = 2;
339 t.bits_per_word = bits;
340 spi_message_add_tail(&t, &m);
341
342 mutex_lock(&edev->lock);
343
344 if (edev->pdata->prepare)
345 edev->pdata->prepare(edev);
346
347 ret = spi_sync(edev->spi, &m);
348 if (ret)
349 dev_err(&edev->spi->dev, "erase error %d\n", ret);
350 /* have to wait erase cycle time Tec ms */
351 mdelay(6);
352
353 if (pd->finish)
354 pd->finish(edev);
355
356 mutex_unlock(&edev->lock);
357 return ret;
358}
359
360static ssize_t eeprom_93xx46_store_erase(struct device *dev,
361 struct device_attribute *attr,
362 const char *buf, size_t count)
363{
364 struct eeprom_93xx46_dev *edev = dev_get_drvdata(dev);
365 int erase = 0, ret;
366
367 sscanf(buf, "%d", &erase);
368 if (erase) {
369 ret = eeprom_93xx46_ew(edev, 1);
370 if (ret)
371 return ret;
372 ret = eeprom_93xx46_eral(edev);
373 if (ret)
374 return ret;
375 ret = eeprom_93xx46_ew(edev, 0);
376 if (ret)
377 return ret;
378 }
379 return count;
380}
381static DEVICE_ATTR(erase, S_IWUSR, NULL, eeprom_93xx46_store_erase);
382
383static void select_assert(void *context)
384{
385 struct eeprom_93xx46_dev *edev = context;
386
387 gpiod_set_value_cansleep(edev->pdata->select, 1);
388}
389
390static void select_deassert(void *context)
391{
392 struct eeprom_93xx46_dev *edev = context;
393
394 gpiod_set_value_cansleep(edev->pdata->select, 0);
395}
396
397static const struct of_device_id eeprom_93xx46_of_table[] = {
398 { .compatible = "eeprom-93xx46", .data = &at93c46_data, },
399 { .compatible = "atmel,at93c46", .data = &at93c46_data, },
400 { .compatible = "atmel,at93c46d", .data = &atmel_at93c46d_data, },
401 { .compatible = "atmel,at93c56", .data = &at93c56_data, },
402 { .compatible = "atmel,at93c66", .data = &at93c66_data, },
403 { .compatible = "microchip,93lc46b", .data = µchip_93lc46b_data, },
404 {}
405};
406MODULE_DEVICE_TABLE(of, eeprom_93xx46_of_table);
407
408static const struct spi_device_id eeprom_93xx46_spi_ids[] = {
409 { .name = "eeprom-93xx46",
410 .driver_data = (kernel_ulong_t)&at93c46_data, },
411 { .name = "at93c46",
412 .driver_data = (kernel_ulong_t)&at93c46_data, },
413 { .name = "at93c46d",
414 .driver_data = (kernel_ulong_t)&atmel_at93c46d_data, },
415 { .name = "at93c56",
416 .driver_data = (kernel_ulong_t)&at93c56_data, },
417 { .name = "at93c66",
418 .driver_data = (kernel_ulong_t)&at93c66_data, },
419 { .name = "93lc46b",
420 .driver_data = (kernel_ulong_t)µchip_93lc46b_data, },
421 {}
422};
423MODULE_DEVICE_TABLE(spi, eeprom_93xx46_spi_ids);
424
425static int eeprom_93xx46_probe_dt(struct spi_device *spi)
426{
427 const struct of_device_id *of_id =
428 of_match_device(eeprom_93xx46_of_table, &spi->dev);
429 struct device_node *np = spi->dev.of_node;
430 struct eeprom_93xx46_platform_data *pd;
431 u32 tmp;
432 int ret;
433
434 pd = devm_kzalloc(&spi->dev, sizeof(*pd), GFP_KERNEL);
435 if (!pd)
436 return -ENOMEM;
437
438 ret = of_property_read_u32(np, "data-size", &tmp);
439 if (ret < 0) {
440 dev_err(&spi->dev, "data-size property not found\n");
441 return ret;
442 }
443
444 if (tmp == 8) {
445 pd->flags |= EE_ADDR8;
446 } else if (tmp == 16) {
447 pd->flags |= EE_ADDR16;
448 } else {
449 dev_err(&spi->dev, "invalid data-size (%d)\n", tmp);
450 return -EINVAL;
451 }
452
453 if (of_property_read_bool(np, "read-only"))
454 pd->flags |= EE_READONLY;
455
456 pd->select = devm_gpiod_get_optional(&spi->dev, "select",
457 GPIOD_OUT_LOW);
458 if (IS_ERR(pd->select))
459 return PTR_ERR(pd->select);
460
461 pd->prepare = select_assert;
462 pd->finish = select_deassert;
463 gpiod_direction_output(pd->select, 0);
464
465 if (of_id->data) {
466 const struct eeprom_93xx46_devtype_data *data = of_id->data;
467
468 pd->quirks = data->quirks;
469 pd->flags |= data->flags;
470 }
471
472 spi->dev.platform_data = pd;
473
474 return 0;
475}
476
477static int eeprom_93xx46_probe(struct spi_device *spi)
478{
479 struct eeprom_93xx46_platform_data *pd;
480 struct eeprom_93xx46_dev *edev;
481 int err;
482
483 if (spi->dev.of_node) {
484 err = eeprom_93xx46_probe_dt(spi);
485 if (err < 0)
486 return err;
487 }
488
489 pd = spi->dev.platform_data;
490 if (!pd) {
491 dev_err(&spi->dev, "missing platform data\n");
492 return -ENODEV;
493 }
494
495 edev = devm_kzalloc(&spi->dev, sizeof(*edev), GFP_KERNEL);
496 if (!edev)
497 return -ENOMEM;
498
499 if (pd->flags & EE_SIZE1K)
500 edev->size = 128;
501 else if (pd->flags & EE_SIZE2K)
502 edev->size = 256;
503 else if (pd->flags & EE_SIZE4K)
504 edev->size = 512;
505 else {
506 dev_err(&spi->dev, "unspecified size\n");
507 return -EINVAL;
508 }
509
510 if (pd->flags & EE_ADDR8)
511 edev->addrlen = ilog2(edev->size);
512 else if (pd->flags & EE_ADDR16)
513 edev->addrlen = ilog2(edev->size) - 1;
514 else {
515 dev_err(&spi->dev, "unspecified address type\n");
516 return -EINVAL;
517 }
518
519 mutex_init(&edev->lock);
520
521 edev->spi = spi;
522 edev->pdata = pd;
523
524 edev->nvmem_config.type = NVMEM_TYPE_EEPROM;
525 edev->nvmem_config.name = dev_name(&spi->dev);
526 edev->nvmem_config.dev = &spi->dev;
527 edev->nvmem_config.read_only = pd->flags & EE_READONLY;
528 edev->nvmem_config.root_only = true;
529 edev->nvmem_config.owner = THIS_MODULE;
530 edev->nvmem_config.compat = true;
531 edev->nvmem_config.base_dev = &spi->dev;
532 edev->nvmem_config.reg_read = eeprom_93xx46_read;
533 edev->nvmem_config.reg_write = eeprom_93xx46_write;
534 edev->nvmem_config.priv = edev;
535 edev->nvmem_config.stride = 4;
536 edev->nvmem_config.word_size = 1;
537 edev->nvmem_config.size = edev->size;
538
539 edev->nvmem = devm_nvmem_register(&spi->dev, &edev->nvmem_config);
540 if (IS_ERR(edev->nvmem))
541 return PTR_ERR(edev->nvmem);
542
543 dev_info(&spi->dev, "%d-bit eeprom containing %d bytes %s\n",
544 (pd->flags & EE_ADDR8) ? 8 : 16,
545 edev->size,
546 (pd->flags & EE_READONLY) ? "(readonly)" : "");
547
548 if (!(pd->flags & EE_READONLY)) {
549 if (device_create_file(&spi->dev, &dev_attr_erase))
550 dev_err(&spi->dev, "can't create erase interface\n");
551 }
552
553 spi_set_drvdata(spi, edev);
554 return 0;
555}
556
557static void eeprom_93xx46_remove(struct spi_device *spi)
558{
559 struct eeprom_93xx46_dev *edev = spi_get_drvdata(spi);
560
561 if (!(edev->pdata->flags & EE_READONLY))
562 device_remove_file(&spi->dev, &dev_attr_erase);
563}
564
565static struct spi_driver eeprom_93xx46_driver = {
566 .driver = {
567 .name = "93xx46",
568 .of_match_table = of_match_ptr(eeprom_93xx46_of_table),
569 },
570 .probe = eeprom_93xx46_probe,
571 .remove = eeprom_93xx46_remove,
572 .id_table = eeprom_93xx46_spi_ids,
573};
574
575module_spi_driver(eeprom_93xx46_driver);
576
577MODULE_LICENSE("GPL");
578MODULE_DESCRIPTION("Driver for 93xx46 EEPROMs");
579MODULE_AUTHOR("Anatolij Gustschin <agust@denx.de>");
580MODULE_ALIAS("spi:93xx46");
581MODULE_ALIAS("spi:eeprom-93xx46");
582MODULE_ALIAS("spi:93lc46b");