aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/w1/w1_ds2433.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/w1/w1_ds2433.c')
-rw-r--r--drivers/w1/w1_ds2433.c329
1 files changed, 0 insertions, 329 deletions
diff --git a/drivers/w1/w1_ds2433.c b/drivers/w1/w1_ds2433.c
deleted file mode 100644
index 1e3d98aac12d..000000000000
--- a/drivers/w1/w1_ds2433.c
+++ /dev/null
@@ -1,329 +0,0 @@
1/*
2 * w1_ds2433.c - w1 family 23 (DS2433) driver
3 *
4 * Copyright (c) 2005 Ben Gardner <bgardner@wabtec.com>
5 *
6 * This source code is licensed under the GNU General Public License,
7 * Version 2. See the file COPYING for more details.
8 */
9
10#include <linux/kernel.h>
11#include <linux/module.h>
12#include <linux/moduleparam.h>
13#include <linux/device.h>
14#include <linux/types.h>
15#include <linux/delay.h>
16#ifdef CONFIG_W1_F23_CRC
17#include <linux/crc16.h>
18
19#define CRC16_INIT 0
20#define CRC16_VALID 0xb001
21
22#endif
23
24#include "w1.h"
25#include "w1_io.h"
26#include "w1_int.h"
27#include "w1_family.h"
28
29MODULE_LICENSE("GPL");
30MODULE_AUTHOR("Ben Gardner <bgardner@wabtec.com>");
31MODULE_DESCRIPTION("w1 family 23 driver for DS2433, 4kb EEPROM");
32
33#define W1_EEPROM_SIZE 512
34#define W1_PAGE_COUNT 16
35#define W1_PAGE_SIZE 32
36#define W1_PAGE_BITS 5
37#define W1_PAGE_MASK 0x1F
38
39#define W1_F23_TIME 300
40
41#define W1_F23_READ_EEPROM 0xF0
42#define W1_F23_WRITE_SCRATCH 0x0F
43#define W1_F23_READ_SCRATCH 0xAA
44#define W1_F23_COPY_SCRATCH 0x55
45
46struct w1_f23_data {
47 u8 memory[W1_EEPROM_SIZE];
48 u32 validcrc;
49};
50
51/**
52 * Check the file size bounds and adjusts count as needed.
53 * This would not be needed if the file size didn't reset to 0 after a write.
54 */
55static inline size_t w1_f23_fix_count(loff_t off, size_t count, size_t size)
56{
57 if (off > size)
58 return 0;
59
60 if ((off + count) > size)
61 return (size - off);
62
63 return count;
64}
65
66#ifdef CONFIG_W1_F23_CRC
67static int w1_f23_refresh_block(struct w1_slave *sl, struct w1_f23_data *data,
68 int block)
69{
70 u8 wrbuf[3];
71 int off = block * W1_PAGE_SIZE;
72
73 if (data->validcrc & (1 << block))
74 return 0;
75
76 if (w1_reset_select_slave(sl)) {
77 data->validcrc = 0;
78 return -EIO;
79 }
80
81 wrbuf[0] = W1_F23_READ_EEPROM;
82 wrbuf[1] = off & 0xff;
83 wrbuf[2] = off >> 8;
84 w1_write_block(sl->master, wrbuf, 3);
85 w1_read_block(sl->master, &data->memory[off], W1_PAGE_SIZE);
86
87 /* cache the block if the CRC is valid */
88 if (crc16(CRC16_INIT, &data->memory[off], W1_PAGE_SIZE) == CRC16_VALID)
89 data->validcrc |= (1 << block);
90
91 return 0;
92}
93#endif /* CONFIG_W1_F23_CRC */
94
95static ssize_t w1_f23_read_bin(struct kobject *kobj, char *buf, loff_t off,
96 size_t count)
97{
98 struct w1_slave *sl = kobj_to_w1_slave(kobj);
99#ifdef CONFIG_W1_F23_CRC
100 struct w1_f23_data *data = sl->family_data;
101 int i, min_page, max_page;
102#else
103 u8 wrbuf[3];
104#endif
105
106 if ((count = w1_f23_fix_count(off, count, W1_EEPROM_SIZE)) == 0)
107 return 0;
108
109 atomic_inc(&sl->refcnt);
110 if (down_interruptible(&sl->master->mutex)) {
111 count = 0;
112 goto out_dec;
113 }
114
115#ifdef CONFIG_W1_F23_CRC
116
117 min_page = (off >> W1_PAGE_BITS);
118 max_page = (off + count - 1) >> W1_PAGE_BITS;
119 for (i = min_page; i <= max_page; i++) {
120 if (w1_f23_refresh_block(sl, data, i)) {
121 count = -EIO;
122 goto out_up;
123 }
124 }
125 memcpy(buf, &data->memory[off], count);
126
127#else /* CONFIG_W1_F23_CRC */
128
129 /* read directly from the EEPROM */
130 if (w1_reset_select_slave(sl)) {
131 count = -EIO;
132 goto out_up;
133 }
134
135 wrbuf[0] = W1_F23_READ_EEPROM;
136 wrbuf[1] = off & 0xff;
137 wrbuf[2] = off >> 8;
138 w1_write_block(sl->master, wrbuf, 3);
139 w1_read_block(sl->master, buf, count);
140
141#endif /* CONFIG_W1_F23_CRC */
142
143out_up:
144 up(&sl->master->mutex);
145out_dec:
146 atomic_dec(&sl->refcnt);
147
148 return count;
149}
150
151/**
152 * Writes to the scratchpad and reads it back for verification.
153 * Then copies the scratchpad to EEPROM.
154 * The data must be on one page.
155 * The master must be locked.
156 *
157 * @param sl The slave structure
158 * @param addr Address for the write
159 * @param len length must be <= (W1_PAGE_SIZE - (addr & W1_PAGE_MASK))
160 * @param data The data to write
161 * @return 0=Success -1=failure
162 */
163static int w1_f23_write(struct w1_slave *sl, int addr, int len, const u8 *data)
164{
165 u8 wrbuf[4];
166 u8 rdbuf[W1_PAGE_SIZE + 3];
167 u8 es = (addr + len - 1) & 0x1f;
168
169 /* Write the data to the scratchpad */
170 if (w1_reset_select_slave(sl))
171 return -1;
172
173 wrbuf[0] = W1_F23_WRITE_SCRATCH;
174 wrbuf[1] = addr & 0xff;
175 wrbuf[2] = addr >> 8;
176
177 w1_write_block(sl->master, wrbuf, 3);
178 w1_write_block(sl->master, data, len);
179
180 /* Read the scratchpad and verify */
181 if (w1_reset_select_slave(sl))
182 return -1;
183
184 w1_write_8(sl->master, W1_F23_READ_SCRATCH);
185 w1_read_block(sl->master, rdbuf, len + 3);
186
187 /* Compare what was read against the data written */
188 if ((rdbuf[0] != wrbuf[1]) || (rdbuf[1] != wrbuf[2]) ||
189 (rdbuf[2] != es) || (memcmp(data, &rdbuf[3], len) != 0))
190 return -1;
191
192 /* Copy the scratchpad to EEPROM */
193 if (w1_reset_select_slave(sl))
194 return -1;
195
196 wrbuf[0] = W1_F23_COPY_SCRATCH;
197 wrbuf[3] = es;
198 w1_write_block(sl->master, wrbuf, 4);
199
200 /* Sleep for 5 ms to wait for the write to complete */
201 msleep(5);
202
203 /* Reset the bus to wake up the EEPROM (this may not be needed) */
204 w1_reset_bus(sl->master);
205
206 return 0;
207}
208
209static ssize_t w1_f23_write_bin(struct kobject *kobj, char *buf, loff_t off,
210 size_t count)
211{
212 struct w1_slave *sl = kobj_to_w1_slave(kobj);
213 int addr, len, idx;
214
215 if ((count = w1_f23_fix_count(off, count, W1_EEPROM_SIZE)) == 0)
216 return 0;
217
218#ifdef CONFIG_W1_F23_CRC
219 /* can only write full blocks in cached mode */
220 if ((off & W1_PAGE_MASK) || (count & W1_PAGE_MASK)) {
221 dev_err(&sl->dev, "invalid offset/count off=%d cnt=%zd\n",
222 (int)off, count);
223 return -EINVAL;
224 }
225
226 /* make sure the block CRCs are valid */
227 for (idx = 0; idx < count; idx += W1_PAGE_SIZE) {
228 if (crc16(CRC16_INIT, &buf[idx], W1_PAGE_SIZE) != CRC16_VALID) {
229 dev_err(&sl->dev, "bad CRC at offset %d\n", (int)off);
230 return -EINVAL;
231 }
232 }
233#endif /* CONFIG_W1_F23_CRC */
234
235 atomic_inc(&sl->refcnt);
236 if (down_interruptible(&sl->master->mutex)) {
237 count = 0;
238 goto out_dec;
239 }
240
241 /* Can only write data to one page at a time */
242 idx = 0;
243 while (idx < count) {
244 addr = off + idx;
245 len = W1_PAGE_SIZE - (addr & W1_PAGE_MASK);
246 if (len > (count - idx))
247 len = count - idx;
248
249 if (w1_f23_write(sl, addr, len, &buf[idx]) < 0) {
250 count = -EIO;
251 goto out_up;
252 }
253 idx += len;
254 }
255
256out_up:
257 up(&sl->master->mutex);
258out_dec:
259 atomic_dec(&sl->refcnt);
260
261 return count;
262}
263
264static struct bin_attribute w1_f23_bin_attr = {
265 .attr = {
266 .name = "eeprom",
267 .mode = S_IRUGO | S_IWUSR,
268 .owner = THIS_MODULE,
269 },
270 .size = W1_EEPROM_SIZE,
271 .read = w1_f23_read_bin,
272 .write = w1_f23_write_bin,
273};
274
275static int w1_f23_add_slave(struct w1_slave *sl)
276{
277 int err;
278#ifdef CONFIG_W1_F23_CRC
279 struct w1_f23_data *data;
280
281 data = kmalloc(sizeof(struct w1_f23_data), GFP_KERNEL);
282 if (!data)
283 return -ENOMEM;
284 memset(data, 0, sizeof(struct w1_f23_data));
285 sl->family_data = data;
286
287#endif /* CONFIG_W1_F23_CRC */
288
289 err = sysfs_create_bin_file(&sl->dev.kobj, &w1_f23_bin_attr);
290
291#ifdef CONFIG_W1_F23_CRC
292 if (err)
293 kfree(data);
294#endif /* CONFIG_W1_F23_CRC */
295
296 return err;
297}
298
299static void w1_f23_remove_slave(struct w1_slave *sl)
300{
301#ifdef CONFIG_W1_F23_CRC
302 kfree(sl->family_data);
303 sl->family_data = NULL;
304#endif /* CONFIG_W1_F23_CRC */
305 sysfs_remove_bin_file(&sl->dev.kobj, &w1_f23_bin_attr);
306}
307
308static struct w1_family_ops w1_f23_fops = {
309 .add_slave = w1_f23_add_slave,
310 .remove_slave = w1_f23_remove_slave,
311};
312
313static struct w1_family w1_family_23 = {
314 .fid = W1_EEPROM_DS2433,
315 .fops = &w1_f23_fops,
316};
317
318static int __init w1_f23_init(void)
319{
320 return w1_register_family(&w1_family_23);
321}
322
323static void __exit w1_f23_fini(void)
324{
325 w1_unregister_family(&w1_family_23);
326}
327
328module_init(w1_f23_init);
329module_exit(w1_f23_fini);
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-23 10:01:53 -0500