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authorLinus Torvalds <torvalds@linux-foundation.org>2012-03-20 14:16:20 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2012-03-20 14:16:20 -0400
commit4a52246302f01596f0edf7b4a3e6425e23479192 (patch)
treef384d86722d3ccfc875e3e5e8d8726e993a922ee /drivers/w1/slaves/w1_ds2781.c
parent9f9d2760da8c7f94fae119fac3e13d5a1702f8f0 (diff)
parentadc80ae60eae24a43a357bf5b30fb496f34aa605 (diff)
Merge tag 'driver-core-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core patches for 3.4-rc1 from Greg KH: "Here's the big driver core merge for 3.4-rc1. Lots of various things here, sysfs fixes/tweaks (with the nlink breakage reverted), dynamic debugging updates, w1 drivers, hyperv driver updates, and a variety of other bits and pieces, full information in the shortlog." * tag 'driver-core-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (78 commits) Tools: hv: Support enumeration from all the pools Tools: hv: Fully support the new KVP verbs in the user level daemon Drivers: hv: Support the newly introduced KVP messages in the driver Drivers: hv: Add new message types to enhance KVP regulator: Support driver probe deferral Revert "sysfs: Kill nlink counting." uevent: send events in correct order according to seqnum (v3) driver core: minor comment formatting cleanups driver core: move the deferred probe pointer into the private area drivercore: Add driver probe deferral mechanism DS2781 Maxim Stand-Alone Fuel Gauge battery and w1 slave drivers w1_bq27000: Only one thread can access the bq27000 at a time. w1_bq27000 - remove w1_bq27000_write w1_bq27000: remove unnecessary NULL test. sysfs: Fix memory leak in sysfs_sd_setsecdata(). intel_idle: Revert change of auto_demotion_disable_flags for Nehalem w1: Fix w1_bq27000 driver-core: documentation: fix up Greg's email address powernow-k6: Really enable auto-loading powernow-k7: Fix CPU family number ...
Diffstat (limited to 'drivers/w1/slaves/w1_ds2781.c')
-rw-r--r--drivers/w1/slaves/w1_ds2781.c201
1 files changed, 201 insertions, 0 deletions
diff --git a/drivers/w1/slaves/w1_ds2781.c b/drivers/w1/slaves/w1_ds2781.c
new file mode 100644
index 000000000000..0d0c7985293f
--- /dev/null
+++ b/drivers/w1/slaves/w1_ds2781.c
@@ -0,0 +1,201 @@
1/*
2 * 1-Wire implementation for the ds2781 chip
3 *
4 * Author: Renata Sayakhova <renata@oktetlabs.ru>
5 *
6 * Based on w1-ds2780 driver
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 *
12 */
13
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/device.h>
17#include <linux/types.h>
18#include <linux/platform_device.h>
19#include <linux/mutex.h>
20#include <linux/idr.h>
21
22#include "../w1.h"
23#include "../w1_int.h"
24#include "../w1_family.h"
25#include "w1_ds2781.h"
26
27static int w1_ds2781_do_io(struct device *dev, char *buf, int addr,
28 size_t count, int io)
29{
30 struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
31
32 if (addr > DS2781_DATA_SIZE || addr < 0)
33 return 0;
34
35 count = min_t(int, count, DS2781_DATA_SIZE - addr);
36
37 if (w1_reset_select_slave(sl) == 0) {
38 if (io) {
39 w1_write_8(sl->master, W1_DS2781_WRITE_DATA);
40 w1_write_8(sl->master, addr);
41 w1_write_block(sl->master, buf, count);
42 } else {
43 w1_write_8(sl->master, W1_DS2781_READ_DATA);
44 w1_write_8(sl->master, addr);
45 count = w1_read_block(sl->master, buf, count);
46 }
47 }
48
49 return count;
50}
51
52int w1_ds2781_io(struct device *dev, char *buf, int addr, size_t count,
53 int io)
54{
55 struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
56 int ret;
57
58 if (!dev)
59 return -ENODEV;
60
61 mutex_lock(&sl->master->mutex);
62
63 ret = w1_ds2781_do_io(dev, buf, addr, count, io);
64
65 mutex_unlock(&sl->master->mutex);
66
67 return ret;
68}
69EXPORT_SYMBOL(w1_ds2781_io);
70
71int w1_ds2781_io_nolock(struct device *dev, char *buf, int addr, size_t count,
72 int io)
73{
74 int ret;
75
76 if (!dev)
77 return -ENODEV;
78
79 ret = w1_ds2781_do_io(dev, buf, addr, count, io);
80
81 return ret;
82}
83EXPORT_SYMBOL(w1_ds2781_io_nolock);
84
85int w1_ds2781_eeprom_cmd(struct device *dev, int addr, int cmd)
86{
87 struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
88
89 if (!dev)
90 return -EINVAL;
91
92 mutex_lock(&sl->master->mutex);
93
94 if (w1_reset_select_slave(sl) == 0) {
95 w1_write_8(sl->master, cmd);
96 w1_write_8(sl->master, addr);
97 }
98
99 mutex_unlock(&sl->master->mutex);
100 return 0;
101}
102EXPORT_SYMBOL(w1_ds2781_eeprom_cmd);
103
104static ssize_t w1_ds2781_read_bin(struct file *filp,
105 struct kobject *kobj,
106 struct bin_attribute *bin_attr,
107 char *buf, loff_t off, size_t count)
108{
109 struct device *dev = container_of(kobj, struct device, kobj);
110 return w1_ds2781_io(dev, buf, off, count, 0);
111}
112
113static struct bin_attribute w1_ds2781_bin_attr = {
114 .attr = {
115 .name = "w1_slave",
116 .mode = S_IRUGO,
117 },
118 .size = DS2781_DATA_SIZE,
119 .read = w1_ds2781_read_bin,
120};
121
122static DEFINE_IDA(bat_ida);
123
124static int w1_ds2781_add_slave(struct w1_slave *sl)
125{
126 int ret;
127 int id;
128 struct platform_device *pdev;
129
130 id = ida_simple_get(&bat_ida, 0, 0, GFP_KERNEL);
131 if (id < 0) {
132 ret = id;
133 goto noid;
134 }
135
136 pdev = platform_device_alloc("ds2781-battery", id);
137 if (!pdev) {
138 ret = -ENOMEM;
139 goto pdev_alloc_failed;
140 }
141 pdev->dev.parent = &sl->dev;
142
143 ret = platform_device_add(pdev);
144 if (ret)
145 goto pdev_add_failed;
146
147 ret = sysfs_create_bin_file(&sl->dev.kobj, &w1_ds2781_bin_attr);
148 if (ret)
149 goto bin_attr_failed;
150
151 dev_set_drvdata(&sl->dev, pdev);
152
153 return 0;
154
155bin_attr_failed:
156pdev_add_failed:
157 platform_device_unregister(pdev);
158pdev_alloc_failed:
159 ida_simple_remove(&bat_ida, id);
160noid:
161 return ret;
162}
163
164static void w1_ds2781_remove_slave(struct w1_slave *sl)
165{
166 struct platform_device *pdev = dev_get_drvdata(&sl->dev);
167 int id = pdev->id;
168
169 platform_device_unregister(pdev);
170 ida_simple_remove(&bat_ida, id);
171 sysfs_remove_bin_file(&sl->dev.kobj, &w1_ds2781_bin_attr);
172}
173
174static struct w1_family_ops w1_ds2781_fops = {
175 .add_slave = w1_ds2781_add_slave,
176 .remove_slave = w1_ds2781_remove_slave,
177};
178
179static struct w1_family w1_ds2781_family = {
180 .fid = W1_FAMILY_DS2781,
181 .fops = &w1_ds2781_fops,
182};
183
184static int __init w1_ds2781_init(void)
185{
186 ida_init(&bat_ida);
187 return w1_register_family(&w1_ds2781_family);
188}
189
190static void __exit w1_ds2781_exit(void)
191{
192 w1_unregister_family(&w1_ds2781_family);
193 ida_destroy(&bat_ida);
194}
195
196module_init(w1_ds2781_init);
197module_exit(w1_ds2781_exit);
198
199MODULE_LICENSE("GPL");
200MODULE_AUTHOR("Renata Sayakhova <renata@oktetlabs.ru>");
201MODULE_DESCRIPTION("1-wire Driver for Maxim/Dallas DS2781 Stand-Alone Fuel Gauge IC");