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authorEvgeniy Polyakov <johnpol@2ka.mipt.ru>2005-08-11 09:27:50 -0400
committerGreg Kroah-Hartman <gregkh@suse.de>2005-09-08 17:41:27 -0400
commit80895392c83e54653540e72e7d40573aac7ee690 (patch)
tree3fb57983caf779f0648baebf18672f232a3c8c58 /drivers/w1
parent7c8f5703de91ade517d4fd6c3cc8e08dbba2b739 (diff)
[PATCH] w1: Added DS2433 driver.
Work by Ben Gardner <bgardner@wabtec.com>. Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/w1')
-rw-r--r--drivers/w1/Kconfig7
-rw-r--r--drivers/w1/Makefile1
-rw-r--r--drivers/w1/w1_ds2433.c222
3 files changed, 230 insertions, 0 deletions
diff --git a/drivers/w1/Kconfig b/drivers/w1/Kconfig
index 711b90903e7b..1d5d0872eb4d 100644
--- a/drivers/w1/Kconfig
+++ b/drivers/w1/Kconfig
@@ -54,4 +54,11 @@ config W1_SMEM
54 Say Y here if you want to connect 1-wire 54 Say Y here if you want to connect 1-wire
55 simple 64bit memory rom(ds2401/ds2411/ds1990*) to you wire. 55 simple 64bit memory rom(ds2401/ds2411/ds1990*) to you wire.
56 56
57config W1_DS2433
58 tristate "4kb EEPROM family support (DS2433)"
59 depends on W1
60 help
61 Say Y here if you want to use a 1-wire
62 4kb EEPROM family device (DS2433).
63
57endmenu 64endmenu
diff --git a/drivers/w1/Makefile b/drivers/w1/Makefile
index 80725c348e70..d894a9896b18 100644
--- a/drivers/w1/Makefile
+++ b/drivers/w1/Makefile
@@ -18,3 +18,4 @@ ds9490r-objs := dscore.o
18 18
19obj-$(CONFIG_W1_DS9490_BRIDGE) += ds_w1_bridge.o 19obj-$(CONFIG_W1_DS9490_BRIDGE) += ds_w1_bridge.o
20 20
21obj-$(CONFIG_W1_DS2433) += w1_ds2433.o
diff --git a/drivers/w1/w1_ds2433.c b/drivers/w1/w1_ds2433.c
new file mode 100644
index 000000000000..9ec9163a0a9b
--- /dev/null
+++ b/drivers/w1/w1_ds2433.c
@@ -0,0 +1,222 @@
1/*
2 * w1_ds2433.c - w1 family 23 (DS2433) driver
3 *
4 * Copyright (c) 2005 Ben Gardner <bgardner@wabtec.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the smems of the GNU General Public License as published by
8 * the Free Software Foundation; version 2 of the License.
9 */
10
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/moduleparam.h>
14#include <linux/device.h>
15#include <linux/types.h>
16#include <linux/delay.h>
17
18#include "w1.h"
19#include "w1_io.h"
20#include "w1_int.h"
21#include "w1_family.h"
22
23MODULE_LICENSE("GPL");
24MODULE_AUTHOR("Ben Gardner <bgardner@wabtec.com>");
25MODULE_DESCRIPTION("w1 family 23 driver for DS2433, 4kb EEPROM");
26
27#define W1_EEPROM_SIZE 512
28#define W1_PAGE_SIZE 32
29#define W1_PAGE_BITS 5
30#define W1_PAGE_MASK 0x1F
31
32#define W1_F23_READ_EEPROM 0xF0
33#define W1_F23_WRITE_SCRATCH 0x0F
34#define W1_F23_READ_SCRATCH 0xAA
35#define W1_F23_COPY_SCRATCH 0x55
36
37/**
38 * Check the file size bounds and adjusts count as needed.
39 * This may not be needed if the sysfs layer checks bounds.
40 */
41static inline size_t w1_f23_fix_count(loff_t off, size_t count, size_t size)
42{
43 if (off > size)
44 return 0;
45
46 if ((off + count) > size)
47 return (size - off);
48
49 return count;
50}
51
52static ssize_t w1_f23_read_bin(struct kobject *kobj, char *buf, loff_t off, size_t count)
53{
54 struct w1_slave *sl = kobj_to_w1_slave(kobj);
55 u8 wrbuf[3];
56
57 if ((count = w1_f23_fix_count(off, count, W1_EEPROM_SIZE)) == 0)
58 return 0;
59
60 atomic_inc(&sl->refcnt);
61 if (down_interruptible(&sl->master->mutex)) {
62 count = 0;
63 goto out_dec;
64 }
65
66 /* read directly from the EEPROM */
67 if (w1_reset_select_slave(sl)) {
68 count = -EIO;
69 goto out_up;
70 }
71
72 wrbuf[0] = W1_F23_READ_EEPROM;
73 wrbuf[1] = off & 0xff;
74 wrbuf[2] = off >> 8;
75 w1_write_block(sl->master, wrbuf, 3);
76 w1_read_block(sl->master, buf, count);
77
78out_up:
79 up(&sl->master->mutex);
80out_dec:
81 atomic_dec(&sl->refcnt);
82
83 return count;
84}
85
86/**
87 * Writes to the scratchpad and reads it back for verification.
88 * The master must be locked.
89 *
90 * @param sl The slave structure
91 * @param addr Address for the write
92 * @param len length must be <= (W1_PAGE_SIZE - (addr & W1_PAGE_MASK))
93 * @param data The data to write
94 * @return 0=Success -1=failure
95 */
96static int w1_f23_write(struct w1_slave *sl, int addr, int len, const u8 *data)
97{
98 u8 wrbuf[4];
99 u8 rdbuf[W1_PAGE_SIZE + 3];
100 u8 es = (addr + len - 1) & 0x1f;
101
102 /* Write the data to the scratchpad */
103 if (w1_reset_select_slave(sl))
104 return -1;
105
106 wrbuf[0] = W1_F23_WRITE_SCRATCH;
107 wrbuf[1] = addr & 0xff;
108 wrbuf[2] = addr >> 8;
109
110 w1_write_block(sl->master, wrbuf, 3);
111 w1_write_block(sl->master, data, len);
112
113 /* Read the scratchpad and verify */
114 if (w1_reset_select_slave(sl))
115 return -1;
116
117 w1_write_8(sl->master, W1_F23_READ_SCRATCH);
118 w1_read_block(sl->master, rdbuf, len + 3);
119
120 /* Compare what was read against the data written */
121 if ((rdbuf[0] != wrbuf[1]) || (rdbuf[1] != wrbuf[2]) ||
122 (rdbuf[2] != es) || (memcmp(data, &rdbuf[3], len) != 0))
123 return -1;
124
125 /* Copy the scratchpad to EEPROM */
126 if (w1_reset_select_slave(sl))
127 return -1;
128
129 wrbuf[0] = W1_F23_COPY_SCRATCH;
130 wrbuf[3] = es;
131 w1_write_block(sl->master, wrbuf, 4);
132
133 /* Sleep for 5 ms to wait for the write to complete */
134 msleep(5);
135
136 /* Reset the bus to wake up the EEPROM (this may not be needed) */
137 w1_reset_bus(sl->master);
138
139 return 0;
140}
141
142static ssize_t w1_f23_write_bin(struct kobject *kobj, char *buf, loff_t off,
143 size_t count)
144{
145 struct w1_slave *sl = kobj_to_w1_slave(kobj);
146 int addr, len, idx;
147
148 if ((count = w1_f23_fix_count(off, count, W1_EEPROM_SIZE)) == 0)
149 return 0;
150
151 atomic_inc(&sl->refcnt);
152 if (down_interruptible(&sl->master->mutex)) {
153 count = 0;
154 goto out_dec;
155 }
156
157 /* Can only write data to one page at a time */
158 idx = 0;
159 while (idx < count) {
160 addr = off + idx;
161 len = W1_PAGE_SIZE - (addr & W1_PAGE_MASK);
162 if (len > (count - idx))
163 len = count - idx;
164
165 if (w1_f23_write(sl, addr, len, &buf[idx]) < 0) {
166 count = -EIO;
167 goto out_up;
168 }
169 idx += len;
170 }
171
172out_up:
173 up(&sl->master->mutex);
174out_dec:
175 atomic_dec(&sl->refcnt);
176
177 return count;
178}
179
180static struct bin_attribute w1_f23_bin_attr = {
181 .attr = {
182 .name = "eeprom",
183 .mode = S_IRUGO | S_IWUSR,
184 .owner = THIS_MODULE,
185 },
186 .size = W1_EEPROM_SIZE,
187 .read = w1_f23_read_bin,
188 .write = w1_f23_write_bin,
189};
190
191static int w1_f23_add_slave(struct w1_slave *sl)
192{
193 return sysfs_create_bin_file(&sl->dev.kobj, &w1_f23_bin_attr);
194}
195
196static void w1_f23_remove_slave(struct w1_slave *sl)
197{
198 sysfs_remove_bin_file(&sl->dev.kobj, &w1_f23_bin_attr);
199}
200
201static struct w1_family_ops w1_f23_fops = {
202 .add_slave = w1_f23_add_slave,
203 .remove_slave = w1_f23_remove_slave,
204};
205
206static struct w1_family w1_family_23 = {
207 .fid = W1_EEPROM_DS2433,
208 .fops = &w1_f23_fops,
209};
210
211static int __init w1_f23_init(void)
212{
213 return w1_register_family(&w1_family_23);
214}
215
216static void __exit w1_f23_fini(void)
217{
218 w1_unregister_family(&w1_family_23);
219}
220
221module_init(w1_f23_init);
222module_exit(w1_f23_fini);