Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 1 | /* |
| 2 | * w1_ds2433.c - w1 family 23 (DS2433) driver |
| 3 | * |
| 4 | * Copyright (c) 2005 Ben Gardner <bgardner@wabtec.com> |
| 5 | * |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 6 | * This source code is licensed under the GNU General Public License, |
| 7 | * Version 2. See the file COPYING for more details. |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 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> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 16 | #include <linux/slab.h> |
Evgeniy Polyakov | e9d55f9 | 2006-12-06 20:39:27 -0800 | [diff] [blame] | 17 | #ifdef CONFIG_W1_SLAVE_DS2433_CRC |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 18 | #include <linux/crc16.h> |
Evgeniy Polyakov | f24ec7f | 2005-09-12 17:12:43 +0400 | [diff] [blame] | 19 | |
| 20 | #define CRC16_INIT 0 |
| 21 | #define CRC16_VALID 0xb001 |
| 22 | |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 23 | #endif |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 24 | |
Evgeniy Polyakov | bd529cf | 2005-12-06 13:38:28 +0300 | [diff] [blame] | 25 | #include "../w1.h" |
Evgeniy Polyakov | bd529cf | 2005-12-06 13:38:28 +0300 | [diff] [blame] | 26 | #include "../w1_int.h" |
| 27 | #include "../w1_family.h" |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 28 | |
| 29 | MODULE_LICENSE("GPL"); |
| 30 | MODULE_AUTHOR("Ben Gardner <bgardner@wabtec.com>"); |
| 31 | MODULE_DESCRIPTION("w1 family 23 driver for DS2433, 4kb EEPROM"); |
Alexander Stein | 8d7bda5 | 2013-05-26 20:06:50 +0200 | [diff] [blame] | 32 | MODULE_ALIAS("w1-family-" __stringify(W1_EEPROM_DS2433)); |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 33 | |
| 34 | #define W1_EEPROM_SIZE 512 |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 35 | #define W1_PAGE_COUNT 16 |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 36 | #define W1_PAGE_SIZE 32 |
| 37 | #define W1_PAGE_BITS 5 |
| 38 | #define W1_PAGE_MASK 0x1F |
| 39 | |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 40 | #define W1_F23_TIME 300 |
| 41 | |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 42 | #define W1_F23_READ_EEPROM 0xF0 |
| 43 | #define W1_F23_WRITE_SCRATCH 0x0F |
| 44 | #define W1_F23_READ_SCRATCH 0xAA |
| 45 | #define W1_F23_COPY_SCRATCH 0x55 |
| 46 | |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 47 | struct w1_f23_data { |
| 48 | u8 memory[W1_EEPROM_SIZE]; |
| 49 | u32 validcrc; |
| 50 | }; |
| 51 | |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 52 | /** |
| 53 | * Check the file size bounds and adjusts count as needed. |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 54 | * This would not be needed if the file size didn't reset to 0 after a write. |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 55 | */ |
| 56 | static inline size_t w1_f23_fix_count(loff_t off, size_t count, size_t size) |
| 57 | { |
| 58 | if (off > size) |
| 59 | return 0; |
| 60 | |
| 61 | if ((off + count) > size) |
| 62 | return (size - off); |
| 63 | |
| 64 | return count; |
| 65 | } |
| 66 | |
Evgeniy Polyakov | e9d55f9 | 2006-12-06 20:39:27 -0800 | [diff] [blame] | 67 | #ifdef CONFIG_W1_SLAVE_DS2433_CRC |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 68 | static int w1_f23_refresh_block(struct w1_slave *sl, struct w1_f23_data *data, |
| 69 | int block) |
| 70 | { |
| 71 | u8 wrbuf[3]; |
| 72 | int off = block * W1_PAGE_SIZE; |
| 73 | |
| 74 | if (data->validcrc & (1 << block)) |
| 75 | return 0; |
| 76 | |
| 77 | if (w1_reset_select_slave(sl)) { |
| 78 | data->validcrc = 0; |
| 79 | return -EIO; |
| 80 | } |
| 81 | |
| 82 | wrbuf[0] = W1_F23_READ_EEPROM; |
| 83 | wrbuf[1] = off & 0xff; |
| 84 | wrbuf[2] = off >> 8; |
| 85 | w1_write_block(sl->master, wrbuf, 3); |
| 86 | w1_read_block(sl->master, &data->memory[off], W1_PAGE_SIZE); |
| 87 | |
| 88 | /* cache the block if the CRC is valid */ |
| 89 | if (crc16(CRC16_INIT, &data->memory[off], W1_PAGE_SIZE) == CRC16_VALID) |
| 90 | data->validcrc |= (1 << block); |
| 91 | |
| 92 | return 0; |
| 93 | } |
Evgeniy Polyakov | e9d55f9 | 2006-12-06 20:39:27 -0800 | [diff] [blame] | 94 | #endif /* CONFIG_W1_SLAVE_DS2433_CRC */ |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 95 | |
Greg Kroah-Hartman | 38f4098 | 2013-08-21 15:45:01 -0700 | [diff] [blame] | 96 | static ssize_t eeprom_read(struct file *filp, struct kobject *kobj, |
| 97 | struct bin_attribute *bin_attr, char *buf, |
| 98 | loff_t off, size_t count) |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 99 | { |
| 100 | struct w1_slave *sl = kobj_to_w1_slave(kobj); |
Evgeniy Polyakov | e9d55f9 | 2006-12-06 20:39:27 -0800 | [diff] [blame] | 101 | #ifdef CONFIG_W1_SLAVE_DS2433_CRC |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 102 | struct w1_f23_data *data = sl->family_data; |
| 103 | int i, min_page, max_page; |
| 104 | #else |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 105 | u8 wrbuf[3]; |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 106 | #endif |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 107 | |
| 108 | if ((count = w1_f23_fix_count(off, count, W1_EEPROM_SIZE)) == 0) |
| 109 | return 0; |
| 110 | |
NeilBrown | b02f8be | 2012-05-18 15:59:52 +1000 | [diff] [blame] | 111 | mutex_lock(&sl->master->bus_mutex); |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 112 | |
Evgeniy Polyakov | e9d55f9 | 2006-12-06 20:39:27 -0800 | [diff] [blame] | 113 | #ifdef CONFIG_W1_SLAVE_DS2433_CRC |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 114 | |
| 115 | min_page = (off >> W1_PAGE_BITS); |
| 116 | max_page = (off + count - 1) >> W1_PAGE_BITS; |
| 117 | for (i = min_page; i <= max_page; i++) { |
| 118 | if (w1_f23_refresh_block(sl, data, i)) { |
| 119 | count = -EIO; |
| 120 | goto out_up; |
| 121 | } |
| 122 | } |
| 123 | memcpy(buf, &data->memory[off], count); |
| 124 | |
Evgeniy Polyakov | e9d55f9 | 2006-12-06 20:39:27 -0800 | [diff] [blame] | 125 | #else /* CONFIG_W1_SLAVE_DS2433_CRC */ |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 126 | |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 127 | /* read directly from the EEPROM */ |
| 128 | if (w1_reset_select_slave(sl)) { |
| 129 | count = -EIO; |
| 130 | goto out_up; |
| 131 | } |
| 132 | |
| 133 | wrbuf[0] = W1_F23_READ_EEPROM; |
| 134 | wrbuf[1] = off & 0xff; |
| 135 | wrbuf[2] = off >> 8; |
| 136 | w1_write_block(sl->master, wrbuf, 3); |
| 137 | w1_read_block(sl->master, buf, count); |
| 138 | |
Evgeniy Polyakov | e9d55f9 | 2006-12-06 20:39:27 -0800 | [diff] [blame] | 139 | #endif /* CONFIG_W1_SLAVE_DS2433_CRC */ |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 140 | |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 141 | out_up: |
NeilBrown | b02f8be | 2012-05-18 15:59:52 +1000 | [diff] [blame] | 142 | mutex_unlock(&sl->master->bus_mutex); |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 143 | |
| 144 | return count; |
| 145 | } |
| 146 | |
| 147 | /** |
| 148 | * Writes to the scratchpad and reads it back for verification. |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 149 | * Then copies the scratchpad to EEPROM. |
| 150 | * The data must be on one page. |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 151 | * The master must be locked. |
| 152 | * |
| 153 | * @param sl The slave structure |
| 154 | * @param addr Address for the write |
| 155 | * @param len length must be <= (W1_PAGE_SIZE - (addr & W1_PAGE_MASK)) |
| 156 | * @param data The data to write |
| 157 | * @return 0=Success -1=failure |
| 158 | */ |
| 159 | static int w1_f23_write(struct w1_slave *sl, int addr, int len, const u8 *data) |
| 160 | { |
Ben Gardner | dca1714 | 2009-02-27 14:02:58 -0800 | [diff] [blame] | 161 | #ifdef CONFIG_W1_SLAVE_DS2433_CRC |
| 162 | struct w1_f23_data *f23 = sl->family_data; |
| 163 | #endif |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 164 | u8 wrbuf[4]; |
| 165 | u8 rdbuf[W1_PAGE_SIZE + 3]; |
| 166 | u8 es = (addr + len - 1) & 0x1f; |
| 167 | |
| 168 | /* Write the data to the scratchpad */ |
| 169 | if (w1_reset_select_slave(sl)) |
| 170 | return -1; |
| 171 | |
| 172 | wrbuf[0] = W1_F23_WRITE_SCRATCH; |
| 173 | wrbuf[1] = addr & 0xff; |
| 174 | wrbuf[2] = addr >> 8; |
| 175 | |
| 176 | w1_write_block(sl->master, wrbuf, 3); |
| 177 | w1_write_block(sl->master, data, len); |
| 178 | |
| 179 | /* Read the scratchpad and verify */ |
| 180 | if (w1_reset_select_slave(sl)) |
| 181 | return -1; |
| 182 | |
| 183 | w1_write_8(sl->master, W1_F23_READ_SCRATCH); |
| 184 | w1_read_block(sl->master, rdbuf, len + 3); |
| 185 | |
| 186 | /* Compare what was read against the data written */ |
| 187 | if ((rdbuf[0] != wrbuf[1]) || (rdbuf[1] != wrbuf[2]) || |
| 188 | (rdbuf[2] != es) || (memcmp(data, &rdbuf[3], len) != 0)) |
| 189 | return -1; |
| 190 | |
| 191 | /* Copy the scratchpad to EEPROM */ |
| 192 | if (w1_reset_select_slave(sl)) |
| 193 | return -1; |
| 194 | |
| 195 | wrbuf[0] = W1_F23_COPY_SCRATCH; |
| 196 | wrbuf[3] = es; |
| 197 | w1_write_block(sl->master, wrbuf, 4); |
| 198 | |
| 199 | /* Sleep for 5 ms to wait for the write to complete */ |
| 200 | msleep(5); |
| 201 | |
| 202 | /* Reset the bus to wake up the EEPROM (this may not be needed) */ |
| 203 | w1_reset_bus(sl->master); |
Ben Gardner | dca1714 | 2009-02-27 14:02:58 -0800 | [diff] [blame] | 204 | #ifdef CONFIG_W1_SLAVE_DS2433_CRC |
| 205 | f23->validcrc &= ~(1 << (addr >> W1_PAGE_BITS)); |
| 206 | #endif |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 207 | return 0; |
| 208 | } |
| 209 | |
Greg Kroah-Hartman | 38f4098 | 2013-08-21 15:45:01 -0700 | [diff] [blame] | 210 | static ssize_t eeprom_write(struct file *filp, struct kobject *kobj, |
| 211 | struct bin_attribute *bin_attr, char *buf, |
| 212 | loff_t off, size_t count) |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 213 | { |
| 214 | struct w1_slave *sl = kobj_to_w1_slave(kobj); |
| 215 | int addr, len, idx; |
| 216 | |
| 217 | if ((count = w1_f23_fix_count(off, count, W1_EEPROM_SIZE)) == 0) |
| 218 | return 0; |
| 219 | |
Evgeniy Polyakov | e9d55f9 | 2006-12-06 20:39:27 -0800 | [diff] [blame] | 220 | #ifdef CONFIG_W1_SLAVE_DS2433_CRC |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 221 | /* can only write full blocks in cached mode */ |
| 222 | if ((off & W1_PAGE_MASK) || (count & W1_PAGE_MASK)) { |
Evgeniy Polyakov | f24ec7f | 2005-09-12 17:12:43 +0400 | [diff] [blame] | 223 | dev_err(&sl->dev, "invalid offset/count off=%d cnt=%zd\n", |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 224 | (int)off, count); |
| 225 | return -EINVAL; |
| 226 | } |
| 227 | |
| 228 | /* make sure the block CRCs are valid */ |
| 229 | for (idx = 0; idx < count; idx += W1_PAGE_SIZE) { |
| 230 | if (crc16(CRC16_INIT, &buf[idx], W1_PAGE_SIZE) != CRC16_VALID) { |
| 231 | dev_err(&sl->dev, "bad CRC at offset %d\n", (int)off); |
| 232 | return -EINVAL; |
| 233 | } |
| 234 | } |
Evgeniy Polyakov | e9d55f9 | 2006-12-06 20:39:27 -0800 | [diff] [blame] | 235 | #endif /* CONFIG_W1_SLAVE_DS2433_CRC */ |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 236 | |
NeilBrown | b02f8be | 2012-05-18 15:59:52 +1000 | [diff] [blame] | 237 | mutex_lock(&sl->master->bus_mutex); |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 238 | |
| 239 | /* Can only write data to one page at a time */ |
| 240 | idx = 0; |
| 241 | while (idx < count) { |
| 242 | addr = off + idx; |
| 243 | len = W1_PAGE_SIZE - (addr & W1_PAGE_MASK); |
| 244 | if (len > (count - idx)) |
| 245 | len = count - idx; |
| 246 | |
| 247 | if (w1_f23_write(sl, addr, len, &buf[idx]) < 0) { |
| 248 | count = -EIO; |
| 249 | goto out_up; |
| 250 | } |
| 251 | idx += len; |
| 252 | } |
| 253 | |
| 254 | out_up: |
NeilBrown | b02f8be | 2012-05-18 15:59:52 +1000 | [diff] [blame] | 255 | mutex_unlock(&sl->master->bus_mutex); |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 256 | |
| 257 | return count; |
| 258 | } |
| 259 | |
Greg Kroah-Hartman | 38f4098 | 2013-08-21 15:45:01 -0700 | [diff] [blame] | 260 | static BIN_ATTR_RW(eeprom, W1_EEPROM_SIZE); |
| 261 | |
| 262 | static struct bin_attribute *w1_f23_bin_attributes[] = { |
| 263 | &bin_attr_eeprom, |
| 264 | NULL, |
| 265 | }; |
| 266 | |
| 267 | static const struct attribute_group w1_f23_group = { |
| 268 | .bin_attrs = w1_f23_bin_attributes, |
| 269 | }; |
| 270 | |
| 271 | static const struct attribute_group *w1_f23_groups[] = { |
| 272 | &w1_f23_group, |
| 273 | NULL, |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 274 | }; |
| 275 | |
| 276 | static int w1_f23_add_slave(struct w1_slave *sl) |
| 277 | { |
Evgeniy Polyakov | e9d55f9 | 2006-12-06 20:39:27 -0800 | [diff] [blame] | 278 | #ifdef CONFIG_W1_SLAVE_DS2433_CRC |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 279 | struct w1_f23_data *data; |
| 280 | |
Yoann Padioleau | dd00cc4 | 2007-07-19 01:49:03 -0700 | [diff] [blame] | 281 | data = kzalloc(sizeof(struct w1_f23_data), GFP_KERNEL); |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 282 | if (!data) |
| 283 | return -ENOMEM; |
Evgeniy Polyakov | 0a25e4d | 2005-08-17 15:24:37 +0400 | [diff] [blame] | 284 | sl->family_data = data; |
| 285 | |
Evgeniy Polyakov | e9d55f9 | 2006-12-06 20:39:27 -0800 | [diff] [blame] | 286 | #endif /* CONFIG_W1_SLAVE_DS2433_CRC */ |
Greg Kroah-Hartman | 38f4098 | 2013-08-21 15:45:01 -0700 | [diff] [blame] | 287 | return 0; |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 288 | } |
| 289 | |
| 290 | static void w1_f23_remove_slave(struct w1_slave *sl) |
| 291 | { |
Evgeniy Polyakov | e9d55f9 | 2006-12-06 20:39:27 -0800 | [diff] [blame] | 292 | #ifdef CONFIG_W1_SLAVE_DS2433_CRC |
Jesper Juhl | 6044ec8 | 2005-11-07 01:01:32 -0800 | [diff] [blame] | 293 | kfree(sl->family_data); |
| 294 | sl->family_data = NULL; |
Evgeniy Polyakov | e9d55f9 | 2006-12-06 20:39:27 -0800 | [diff] [blame] | 295 | #endif /* CONFIG_W1_SLAVE_DS2433_CRC */ |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 296 | } |
| 297 | |
| 298 | static struct w1_family_ops w1_f23_fops = { |
| 299 | .add_slave = w1_f23_add_slave, |
| 300 | .remove_slave = w1_f23_remove_slave, |
Greg Kroah-Hartman | 38f4098 | 2013-08-21 15:45:01 -0700 | [diff] [blame] | 301 | .groups = w1_f23_groups, |
Evgeniy Polyakov | 8089539 | 2005-08-11 17:27:50 +0400 | [diff] [blame] | 302 | }; |
| 303 | |
| 304 | static struct w1_family w1_family_23 = { |
| 305 | .fid = W1_EEPROM_DS2433, |
| 306 | .fops = &w1_f23_fops, |
| 307 | }; |
Andrew F. Davis | 939fc83 | 2016-08-02 14:07:09 -0700 | [diff] [blame] | 308 | module_w1_family(w1_family_23); |