diff options
-rw-r--r-- | Documentation/misc-devices/ad525x_dpot.txt | 57 | ||||
-rw-r--r-- | drivers/misc/Kconfig | 14 | ||||
-rw-r--r-- | drivers/misc/Makefile | 1 | ||||
-rw-r--r-- | drivers/misc/ad525x_dpot.c | 666 |
4 files changed, 738 insertions, 0 deletions
diff --git a/Documentation/misc-devices/ad525x_dpot.txt b/Documentation/misc-devices/ad525x_dpot.txt new file mode 100644 index 000000000000..0c9413b1cbf3 --- /dev/null +++ b/Documentation/misc-devices/ad525x_dpot.txt | |||
@@ -0,0 +1,57 @@ | |||
1 | --------------------------------- | ||
2 | AD525x Digital Potentiometers | ||
3 | --------------------------------- | ||
4 | |||
5 | The ad525x_dpot driver exports a simple sysfs interface. This allows you to | ||
6 | work with the immediate resistance settings as well as update the saved startup | ||
7 | settings. Access to the factory programmed tolerance is also provided, but | ||
8 | interpretation of this settings is required by the end application according to | ||
9 | the specific part in use. | ||
10 | |||
11 | --------- | ||
12 | Files | ||
13 | --------- | ||
14 | |||
15 | Each dpot device will have a set of eeprom, rdac, and tolerance files. How | ||
16 | many depends on the actual part you have, as will the range of allowed values. | ||
17 | |||
18 | The eeprom files are used to program the startup value of the device. | ||
19 | |||
20 | The rdac files are used to program the immediate value of the device. | ||
21 | |||
22 | The tolerance files are the read-only factory programmed tolerance settings | ||
23 | and may vary greatly on a part-by-part basis. For exact interpretation of | ||
24 | this field, please consult the datasheet for your part. This is presented | ||
25 | as a hex file for easier parsing. | ||
26 | |||
27 | ----------- | ||
28 | Example | ||
29 | ----------- | ||
30 | |||
31 | Locate the device in your sysfs tree. This is probably easiest by going into | ||
32 | the common i2c directory and locating the device by the i2c slave address. | ||
33 | |||
34 | # ls /sys/bus/i2c/devices/ | ||
35 | 0-0022 0-0027 0-002f | ||
36 | |||
37 | So assuming the device in question is on the first i2c bus and has the slave | ||
38 | address of 0x2f, we descend (unrelated sysfs entries have been trimmed). | ||
39 | |||
40 | # ls /sys/bus/i2c/devices/0-002f/ | ||
41 | eeprom0 rdac0 tolerance0 | ||
42 | |||
43 | You can use simple reads/writes to access these files: | ||
44 | |||
45 | # cd /sys/bus/i2c/devices/0-002f/ | ||
46 | |||
47 | # cat eeprom0 | ||
48 | 0 | ||
49 | # echo 10 > eeprom0 | ||
50 | # cat eeprom0 | ||
51 | 10 | ||
52 | |||
53 | # cat rdac0 | ||
54 | 5 | ||
55 | # echo 3 > rdac0 | ||
56 | # cat rdac0 | ||
57 | 3 | ||
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index 2c16ca6501d5..0c7f4c5dd07f 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig | |||
@@ -13,6 +13,20 @@ menuconfig MISC_DEVICES | |||
13 | 13 | ||
14 | if MISC_DEVICES | 14 | if MISC_DEVICES |
15 | 15 | ||
16 | config AD525X_DPOT | ||
17 | tristate "Analog Devices AD525x Digital Potentiometers" | ||
18 | depends on I2C && SYSFS | ||
19 | help | ||
20 | If you say yes here, you get support for the Analog Devices | ||
21 | AD5258, AD5259, AD5251, AD5252, AD5253, AD5254 and AD5255 | ||
22 | digital potentiometer chips. | ||
23 | |||
24 | See Documentation/misc-devices/ad525x_dpot.txt for the | ||
25 | userspace interface. | ||
26 | |||
27 | This driver can also be built as a module. If so, the module | ||
28 | will be called ad525x_dpot. | ||
29 | |||
16 | config ATMEL_PWM | 30 | config ATMEL_PWM |
17 | tristate "Atmel AT32/AT91 PWM support" | 31 | tristate "Atmel AT32/AT91 PWM support" |
18 | depends on AVR32 || ARCH_AT91SAM9263 || ARCH_AT91SAM9RL || ARCH_AT91CAP9 | 32 | depends on AVR32 || ARCH_AT91SAM9263 || ARCH_AT91SAM9RL || ARCH_AT91CAP9 |
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index 906a0edcea40..18c8418a5132 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile | |||
@@ -4,6 +4,7 @@ | |||
4 | 4 | ||
5 | obj-$(CONFIG_IBM_ASM) += ibmasm/ | 5 | obj-$(CONFIG_IBM_ASM) += ibmasm/ |
6 | obj-$(CONFIG_HDPU_FEATURES) += hdpuftrs/ | 6 | obj-$(CONFIG_HDPU_FEATURES) += hdpuftrs/ |
7 | obj-$(CONFIG_AD525X_DPOT) += ad525x_dpot.o | ||
7 | obj-$(CONFIG_ATMEL_PWM) += atmel_pwm.o | 8 | obj-$(CONFIG_ATMEL_PWM) += atmel_pwm.o |
8 | obj-$(CONFIG_ATMEL_SSC) += atmel-ssc.o | 9 | obj-$(CONFIG_ATMEL_SSC) += atmel-ssc.o |
9 | obj-$(CONFIG_ATMEL_TCLIB) += atmel_tclib.o | 10 | obj-$(CONFIG_ATMEL_TCLIB) += atmel_tclib.o |
diff --git a/drivers/misc/ad525x_dpot.c b/drivers/misc/ad525x_dpot.c new file mode 100644 index 000000000000..30a59f2bacd2 --- /dev/null +++ b/drivers/misc/ad525x_dpot.c | |||
@@ -0,0 +1,666 @@ | |||
1 | /* | ||
2 | * ad525x_dpot: Driver for the Analog Devices AD525x digital potentiometers | ||
3 | * Copyright (c) 2009 Analog Devices, Inc. | ||
4 | * Author: Michael Hennerich <hennerich@blackfin.uclinux.org> | ||
5 | * | ||
6 | * DEVID #Wipers #Positions Resistor Options (kOhm) | ||
7 | * AD5258 1 64 1, 10, 50, 100 | ||
8 | * AD5259 1 256 5, 10, 50, 100 | ||
9 | * AD5251 2 64 1, 10, 50, 100 | ||
10 | * AD5252 2 256 1, 10, 50, 100 | ||
11 | * AD5255 3 512 25, 250 | ||
12 | * AD5253 4 64 1, 10, 50, 100 | ||
13 | * AD5254 4 256 1, 10, 50, 100 | ||
14 | * | ||
15 | * See Documentation/misc-devices/ad525x_dpot.txt for more info. | ||
16 | * | ||
17 | * derived from ad5258.c | ||
18 | * Copyright (c) 2009 Cyber Switching, Inc. | ||
19 | * Author: Chris Verges <chrisv@cyberswitching.com> | ||
20 | * | ||
21 | * derived from ad5252.c | ||
22 | * Copyright (c) 2006 Michael Hennerich <hennerich@blackfin.uclinux.org> | ||
23 | * | ||
24 | * Licensed under the GPL-2 or later. | ||
25 | */ | ||
26 | |||
27 | #include <linux/module.h> | ||
28 | #include <linux/device.h> | ||
29 | #include <linux/kernel.h> | ||
30 | #include <linux/init.h> | ||
31 | #include <linux/slab.h> | ||
32 | #include <linux/i2c.h> | ||
33 | #include <linux/delay.h> | ||
34 | |||
35 | #define DRIVER_NAME "ad525x_dpot" | ||
36 | #define DRIVER_VERSION "0.1" | ||
37 | |||
38 | enum dpot_devid { | ||
39 | AD5258_ID, | ||
40 | AD5259_ID, | ||
41 | AD5251_ID, | ||
42 | AD5252_ID, | ||
43 | AD5253_ID, | ||
44 | AD5254_ID, | ||
45 | AD5255_ID, | ||
46 | }; | ||
47 | |||
48 | #define AD5258_MAX_POSITION 64 | ||
49 | #define AD5259_MAX_POSITION 256 | ||
50 | #define AD5251_MAX_POSITION 64 | ||
51 | #define AD5252_MAX_POSITION 256 | ||
52 | #define AD5253_MAX_POSITION 64 | ||
53 | #define AD5254_MAX_POSITION 256 | ||
54 | #define AD5255_MAX_POSITION 512 | ||
55 | |||
56 | #define AD525X_RDAC0 0 | ||
57 | #define AD525X_RDAC1 1 | ||
58 | #define AD525X_RDAC2 2 | ||
59 | #define AD525X_RDAC3 3 | ||
60 | |||
61 | #define AD525X_REG_TOL 0x18 | ||
62 | #define AD525X_TOL_RDAC0 (AD525X_REG_TOL | AD525X_RDAC0) | ||
63 | #define AD525X_TOL_RDAC1 (AD525X_REG_TOL | AD525X_RDAC1) | ||
64 | #define AD525X_TOL_RDAC2 (AD525X_REG_TOL | AD525X_RDAC2) | ||
65 | #define AD525X_TOL_RDAC3 (AD525X_REG_TOL | AD525X_RDAC3) | ||
66 | |||
67 | /* RDAC-to-EEPROM Interface Commands */ | ||
68 | #define AD525X_I2C_RDAC (0x00 << 5) | ||
69 | #define AD525X_I2C_EEPROM (0x01 << 5) | ||
70 | #define AD525X_I2C_CMD (0x80) | ||
71 | |||
72 | #define AD525X_DEC_ALL_6DB (AD525X_I2C_CMD | (0x4 << 3)) | ||
73 | #define AD525X_INC_ALL_6DB (AD525X_I2C_CMD | (0x9 << 3)) | ||
74 | #define AD525X_DEC_ALL (AD525X_I2C_CMD | (0x6 << 3)) | ||
75 | #define AD525X_INC_ALL (AD525X_I2C_CMD | (0xB << 3)) | ||
76 | |||
77 | static s32 ad525x_read(struct i2c_client *client, u8 reg); | ||
78 | static s32 ad525x_write(struct i2c_client *client, u8 reg, u8 value); | ||
79 | |||
80 | /* | ||
81 | * Client data (each client gets its own) | ||
82 | */ | ||
83 | |||
84 | struct dpot_data { | ||
85 | struct mutex update_lock; | ||
86 | unsigned rdac_mask; | ||
87 | unsigned max_pos; | ||
88 | unsigned devid; | ||
89 | }; | ||
90 | |||
91 | /* sysfs functions */ | ||
92 | |||
93 | static ssize_t sysfs_show_reg(struct device *dev, | ||
94 | struct device_attribute *attr, char *buf, u32 reg) | ||
95 | { | ||
96 | struct i2c_client *client = to_i2c_client(dev); | ||
97 | struct dpot_data *data = i2c_get_clientdata(client); | ||
98 | s32 value; | ||
99 | |||
100 | mutex_lock(&data->update_lock); | ||
101 | value = ad525x_read(client, reg); | ||
102 | mutex_unlock(&data->update_lock); | ||
103 | |||
104 | if (value < 0) | ||
105 | return -EINVAL; | ||
106 | /* | ||
107 | * Let someone else deal with converting this ... | ||
108 | * the tolerance is a two-byte value where the MSB | ||
109 | * is a sign + integer value, and the LSB is a | ||
110 | * decimal value. See page 18 of the AD5258 | ||
111 | * datasheet (Rev. A) for more details. | ||
112 | */ | ||
113 | |||
114 | if (reg & AD525X_REG_TOL) | ||
115 | return sprintf(buf, "0x%04x\n", value & 0xFFFF); | ||
116 | else | ||
117 | return sprintf(buf, "%u\n", value & data->rdac_mask); | ||
118 | } | ||
119 | |||
120 | static ssize_t sysfs_set_reg(struct device *dev, | ||
121 | struct device_attribute *attr, | ||
122 | const char *buf, size_t count, u32 reg) | ||
123 | { | ||
124 | struct i2c_client *client = to_i2c_client(dev); | ||
125 | struct dpot_data *data = i2c_get_clientdata(client); | ||
126 | unsigned long value; | ||
127 | int err; | ||
128 | |||
129 | err = strict_strtoul(buf, 10, &value); | ||
130 | if (err) | ||
131 | return err; | ||
132 | |||
133 | if (value > data->rdac_mask) | ||
134 | value = data->rdac_mask; | ||
135 | |||
136 | mutex_lock(&data->update_lock); | ||
137 | ad525x_write(client, reg, value); | ||
138 | if (reg & AD525X_I2C_EEPROM) | ||
139 | msleep(26); /* Sleep while the EEPROM updates */ | ||
140 | mutex_unlock(&data->update_lock); | ||
141 | |||
142 | return count; | ||
143 | } | ||
144 | |||
145 | static ssize_t sysfs_do_cmd(struct device *dev, | ||
146 | struct device_attribute *attr, | ||
147 | const char *buf, size_t count, u32 reg) | ||
148 | { | ||
149 | struct i2c_client *client = to_i2c_client(dev); | ||
150 | struct dpot_data *data = i2c_get_clientdata(client); | ||
151 | |||
152 | mutex_lock(&data->update_lock); | ||
153 | ad525x_write(client, reg, 0); | ||
154 | mutex_unlock(&data->update_lock); | ||
155 | |||
156 | return count; | ||
157 | } | ||
158 | |||
159 | /* ------------------------------------------------------------------------- */ | ||
160 | |||
161 | static ssize_t show_rdac0(struct device *dev, | ||
162 | struct device_attribute *attr, char *buf) | ||
163 | { | ||
164 | return sysfs_show_reg(dev, attr, buf, AD525X_I2C_RDAC | AD525X_RDAC0); | ||
165 | } | ||
166 | |||
167 | static ssize_t set_rdac0(struct device *dev, | ||
168 | struct device_attribute *attr, | ||
169 | const char *buf, size_t count) | ||
170 | { | ||
171 | return sysfs_set_reg(dev, attr, buf, count, | ||
172 | AD525X_I2C_RDAC | AD525X_RDAC0); | ||
173 | } | ||
174 | |||
175 | static DEVICE_ATTR(rdac0, S_IWUSR | S_IRUGO, show_rdac0, set_rdac0); | ||
176 | |||
177 | static ssize_t show_eeprom0(struct device *dev, | ||
178 | struct device_attribute *attr, char *buf) | ||
179 | { | ||
180 | return sysfs_show_reg(dev, attr, buf, AD525X_I2C_EEPROM | AD525X_RDAC0); | ||
181 | } | ||
182 | |||
183 | static ssize_t set_eeprom0(struct device *dev, | ||
184 | struct device_attribute *attr, | ||
185 | const char *buf, size_t count) | ||
186 | { | ||
187 | return sysfs_set_reg(dev, attr, buf, count, | ||
188 | AD525X_I2C_EEPROM | AD525X_RDAC0); | ||
189 | } | ||
190 | |||
191 | static DEVICE_ATTR(eeprom0, S_IWUSR | S_IRUGO, show_eeprom0, set_eeprom0); | ||
192 | |||
193 | static ssize_t show_tolerance0(struct device *dev, | ||
194 | struct device_attribute *attr, char *buf) | ||
195 | { | ||
196 | return sysfs_show_reg(dev, attr, buf, | ||
197 | AD525X_I2C_EEPROM | AD525X_TOL_RDAC0); | ||
198 | } | ||
199 | |||
200 | static DEVICE_ATTR(tolerance0, S_IRUGO, show_tolerance0, NULL); | ||
201 | |||
202 | /* ------------------------------------------------------------------------- */ | ||
203 | |||
204 | static ssize_t show_rdac1(struct device *dev, | ||
205 | struct device_attribute *attr, char *buf) | ||
206 | { | ||
207 | return sysfs_show_reg(dev, attr, buf, AD525X_I2C_RDAC | AD525X_RDAC1); | ||
208 | } | ||
209 | |||
210 | static ssize_t set_rdac1(struct device *dev, | ||
211 | struct device_attribute *attr, | ||
212 | const char *buf, size_t count) | ||
213 | { | ||
214 | return sysfs_set_reg(dev, attr, buf, count, | ||
215 | AD525X_I2C_RDAC | AD525X_RDAC1); | ||
216 | } | ||
217 | |||
218 | static DEVICE_ATTR(rdac1, S_IWUSR | S_IRUGO, show_rdac1, set_rdac1); | ||
219 | |||
220 | static ssize_t show_eeprom1(struct device *dev, | ||
221 | struct device_attribute *attr, char *buf) | ||
222 | { | ||
223 | return sysfs_show_reg(dev, attr, buf, AD525X_I2C_EEPROM | AD525X_RDAC1); | ||
224 | } | ||
225 | |||
226 | static ssize_t set_eeprom1(struct device *dev, | ||
227 | struct device_attribute *attr, | ||
228 | const char *buf, size_t count) | ||
229 | { | ||
230 | return sysfs_set_reg(dev, attr, buf, count, | ||
231 | AD525X_I2C_EEPROM | AD525X_RDAC1); | ||
232 | } | ||
233 | |||
234 | static DEVICE_ATTR(eeprom1, S_IWUSR | S_IRUGO, show_eeprom1, set_eeprom1); | ||
235 | |||
236 | static ssize_t show_tolerance1(struct device *dev, | ||
237 | struct device_attribute *attr, char *buf) | ||
238 | { | ||
239 | return sysfs_show_reg(dev, attr, buf, | ||
240 | AD525X_I2C_EEPROM | AD525X_TOL_RDAC1); | ||
241 | } | ||
242 | |||
243 | static DEVICE_ATTR(tolerance1, S_IRUGO, show_tolerance1, NULL); | ||
244 | |||
245 | /* ------------------------------------------------------------------------- */ | ||
246 | |||
247 | static ssize_t show_rdac2(struct device *dev, | ||
248 | struct device_attribute *attr, char *buf) | ||
249 | { | ||
250 | return sysfs_show_reg(dev, attr, buf, AD525X_I2C_RDAC | AD525X_RDAC2); | ||
251 | } | ||
252 | |||
253 | static ssize_t set_rdac2(struct device *dev, | ||
254 | struct device_attribute *attr, | ||
255 | const char *buf, size_t count) | ||
256 | { | ||
257 | return sysfs_set_reg(dev, attr, buf, count, | ||
258 | AD525X_I2C_RDAC | AD525X_RDAC2); | ||
259 | } | ||
260 | |||
261 | static DEVICE_ATTR(rdac2, S_IWUSR | S_IRUGO, show_rdac2, set_rdac2); | ||
262 | |||
263 | static ssize_t show_eeprom2(struct device *dev, | ||
264 | struct device_attribute *attr, char *buf) | ||
265 | { | ||
266 | return sysfs_show_reg(dev, attr, buf, AD525X_I2C_EEPROM | AD525X_RDAC2); | ||
267 | } | ||
268 | |||
269 | static ssize_t set_eeprom2(struct device *dev, | ||
270 | struct device_attribute *attr, | ||
271 | const char *buf, size_t count) | ||
272 | { | ||
273 | return sysfs_set_reg(dev, attr, buf, count, | ||
274 | AD525X_I2C_EEPROM | AD525X_RDAC2); | ||
275 | } | ||
276 | |||
277 | static DEVICE_ATTR(eeprom2, S_IWUSR | S_IRUGO, show_eeprom2, set_eeprom2); | ||
278 | |||
279 | static ssize_t show_tolerance2(struct device *dev, | ||
280 | struct device_attribute *attr, char *buf) | ||
281 | { | ||
282 | return sysfs_show_reg(dev, attr, buf, | ||
283 | AD525X_I2C_EEPROM | AD525X_TOL_RDAC2); | ||
284 | } | ||
285 | |||
286 | static DEVICE_ATTR(tolerance2, S_IRUGO, show_tolerance2, NULL); | ||
287 | |||
288 | /* ------------------------------------------------------------------------- */ | ||
289 | |||
290 | static ssize_t show_rdac3(struct device *dev, | ||
291 | struct device_attribute *attr, char *buf) | ||
292 | { | ||
293 | return sysfs_show_reg(dev, attr, buf, AD525X_I2C_RDAC | AD525X_RDAC3); | ||
294 | } | ||
295 | |||
296 | static ssize_t set_rdac3(struct device *dev, | ||
297 | struct device_attribute *attr, | ||
298 | const char *buf, size_t count) | ||
299 | { | ||
300 | return sysfs_set_reg(dev, attr, buf, count, | ||
301 | AD525X_I2C_RDAC | AD525X_RDAC3); | ||
302 | } | ||
303 | |||
304 | static DEVICE_ATTR(rdac3, S_IWUSR | S_IRUGO, show_rdac3, set_rdac3); | ||
305 | |||
306 | static ssize_t show_eeprom3(struct device *dev, | ||
307 | struct device_attribute *attr, char *buf) | ||
308 | { | ||
309 | return sysfs_show_reg(dev, attr, buf, AD525X_I2C_EEPROM | AD525X_RDAC3); | ||
310 | } | ||
311 | |||
312 | static ssize_t set_eeprom3(struct device *dev, | ||
313 | struct device_attribute *attr, | ||
314 | const char *buf, size_t count) | ||
315 | { | ||
316 | return sysfs_set_reg(dev, attr, buf, count, | ||
317 | AD525X_I2C_EEPROM | AD525X_RDAC3); | ||
318 | } | ||
319 | |||
320 | static DEVICE_ATTR(eeprom3, S_IWUSR | S_IRUGO, show_eeprom3, set_eeprom3); | ||
321 | |||
322 | static ssize_t show_tolerance3(struct device *dev, | ||
323 | struct device_attribute *attr, char *buf) | ||
324 | { | ||
325 | return sysfs_show_reg(dev, attr, buf, | ||
326 | AD525X_I2C_EEPROM | AD525X_TOL_RDAC3); | ||
327 | } | ||
328 | |||
329 | static DEVICE_ATTR(tolerance3, S_IRUGO, show_tolerance3, NULL); | ||
330 | |||
331 | static struct attribute *ad525x_attributes_wipers[4][4] = { | ||
332 | { | ||
333 | &dev_attr_rdac0.attr, | ||
334 | &dev_attr_eeprom0.attr, | ||
335 | &dev_attr_tolerance0.attr, | ||
336 | NULL | ||
337 | }, { | ||
338 | &dev_attr_rdac1.attr, | ||
339 | &dev_attr_eeprom1.attr, | ||
340 | &dev_attr_tolerance1.attr, | ||
341 | NULL | ||
342 | }, { | ||
343 | &dev_attr_rdac2.attr, | ||
344 | &dev_attr_eeprom2.attr, | ||
345 | &dev_attr_tolerance2.attr, | ||
346 | NULL | ||
347 | }, { | ||
348 | &dev_attr_rdac3.attr, | ||
349 | &dev_attr_eeprom3.attr, | ||
350 | &dev_attr_tolerance3.attr, | ||
351 | NULL | ||
352 | } | ||
353 | }; | ||
354 | |||
355 | static const struct attribute_group ad525x_group_wipers[] = { | ||
356 | {.attrs = ad525x_attributes_wipers[AD525X_RDAC0]}, | ||
357 | {.attrs = ad525x_attributes_wipers[AD525X_RDAC1]}, | ||
358 | {.attrs = ad525x_attributes_wipers[AD525X_RDAC2]}, | ||
359 | {.attrs = ad525x_attributes_wipers[AD525X_RDAC3]}, | ||
360 | }; | ||
361 | |||
362 | /* ------------------------------------------------------------------------- */ | ||
363 | |||
364 | static ssize_t set_inc_all(struct device *dev, | ||
365 | struct device_attribute *attr, | ||
366 | const char *buf, size_t count) | ||
367 | { | ||
368 | return sysfs_do_cmd(dev, attr, buf, count, AD525X_INC_ALL); | ||
369 | } | ||
370 | |||
371 | static DEVICE_ATTR(inc_all, S_IWUSR, NULL, set_inc_all); | ||
372 | |||
373 | static ssize_t set_dec_all(struct device *dev, | ||
374 | struct device_attribute *attr, | ||
375 | const char *buf, size_t count) | ||
376 | { | ||
377 | return sysfs_do_cmd(dev, attr, buf, count, AD525X_DEC_ALL); | ||
378 | } | ||
379 | |||
380 | static DEVICE_ATTR(dec_all, S_IWUSR, NULL, set_dec_all); | ||
381 | |||
382 | static ssize_t set_inc_all_6db(struct device *dev, | ||
383 | struct device_attribute *attr, | ||
384 | const char *buf, size_t count) | ||
385 | { | ||
386 | return sysfs_do_cmd(dev, attr, buf, count, AD525X_INC_ALL_6DB); | ||
387 | } | ||
388 | |||
389 | static DEVICE_ATTR(inc_all_6db, S_IWUSR, NULL, set_inc_all_6db); | ||
390 | |||
391 | static ssize_t set_dec_all_6db(struct device *dev, | ||
392 | struct device_attribute *attr, | ||
393 | const char *buf, size_t count) | ||
394 | { | ||
395 | return sysfs_do_cmd(dev, attr, buf, count, AD525X_DEC_ALL_6DB); | ||
396 | } | ||
397 | |||
398 | static DEVICE_ATTR(dec_all_6db, S_IWUSR, NULL, set_dec_all_6db); | ||
399 | |||
400 | static struct attribute *ad525x_attributes_commands[] = { | ||
401 | &dev_attr_inc_all.attr, | ||
402 | &dev_attr_dec_all.attr, | ||
403 | &dev_attr_inc_all_6db.attr, | ||
404 | &dev_attr_dec_all_6db.attr, | ||
405 | NULL | ||
406 | }; | ||
407 | |||
408 | static const struct attribute_group ad525x_group_commands = { | ||
409 | .attrs = ad525x_attributes_commands, | ||
410 | }; | ||
411 | |||
412 | /* ------------------------------------------------------------------------- */ | ||
413 | |||
414 | /* i2c device functions */ | ||
415 | |||
416 | /** | ||
417 | * ad525x_read - return the value contained in the specified register | ||
418 | * on the AD5258 device. | ||
419 | * @client: value returned from i2c_new_device() | ||
420 | * @reg: the register to read | ||
421 | * | ||
422 | * If the tolerance register is specified, 2 bytes are returned. | ||
423 | * Otherwise, 1 byte is returned. A negative value indicates an error | ||
424 | * occurred while reading the register. | ||
425 | */ | ||
426 | static s32 ad525x_read(struct i2c_client *client, u8 reg) | ||
427 | { | ||
428 | struct dpot_data *data = i2c_get_clientdata(client); | ||
429 | |||
430 | if ((reg & AD525X_REG_TOL) || (data->max_pos > 256)) | ||
431 | return i2c_smbus_read_word_data(client, (reg & 0xF8) | | ||
432 | ((reg & 0x7) << 1)); | ||
433 | else | ||
434 | return i2c_smbus_read_byte_data(client, reg); | ||
435 | } | ||
436 | |||
437 | /** | ||
438 | * ad525x_write - store the given value in the specified register on | ||
439 | * the AD5258 device. | ||
440 | * @client: value returned from i2c_new_device() | ||
441 | * @reg: the register to write | ||
442 | * @value: the byte to store in the register | ||
443 | * | ||
444 | * For certain instructions that do not require a data byte, "NULL" | ||
445 | * should be specified for the "value" parameter. These instructions | ||
446 | * include NOP, RESTORE_FROM_EEPROM, and STORE_TO_EEPROM. | ||
447 | * | ||
448 | * A negative return value indicates an error occurred while reading | ||
449 | * the register. | ||
450 | */ | ||
451 | static s32 ad525x_write(struct i2c_client *client, u8 reg, u8 value) | ||
452 | { | ||
453 | struct dpot_data *data = i2c_get_clientdata(client); | ||
454 | |||
455 | /* Only write the instruction byte for certain commands */ | ||
456 | if (reg & AD525X_I2C_CMD) | ||
457 | return i2c_smbus_write_byte(client, reg); | ||
458 | |||
459 | if (data->max_pos > 256) | ||
460 | return i2c_smbus_write_word_data(client, (reg & 0xF8) | | ||
461 | ((reg & 0x7) << 1), value); | ||
462 | else | ||
463 | /* All other registers require instruction + data bytes */ | ||
464 | return i2c_smbus_write_byte_data(client, reg, value); | ||
465 | } | ||
466 | |||
467 | static int ad525x_probe(struct i2c_client *client, | ||
468 | const struct i2c_device_id *id) | ||
469 | { | ||
470 | struct device *dev = &client->dev; | ||
471 | struct dpot_data *data; | ||
472 | int err = 0; | ||
473 | |||
474 | dev_dbg(dev, "%s\n", __func__); | ||
475 | |||
476 | if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE)) { | ||
477 | dev_err(dev, "missing I2C functionality for this driver\n"); | ||
478 | goto exit; | ||
479 | } | ||
480 | |||
481 | data = kzalloc(sizeof(struct dpot_data), GFP_KERNEL); | ||
482 | if (!data) { | ||
483 | err = -ENOMEM; | ||
484 | goto exit; | ||
485 | } | ||
486 | |||
487 | i2c_set_clientdata(client, data); | ||
488 | mutex_init(&data->update_lock); | ||
489 | |||
490 | switch (id->driver_data) { | ||
491 | case AD5258_ID: | ||
492 | data->max_pos = AD5258_MAX_POSITION; | ||
493 | err = sysfs_create_group(&dev->kobj, | ||
494 | &ad525x_group_wipers[AD525X_RDAC0]); | ||
495 | break; | ||
496 | case AD5259_ID: | ||
497 | data->max_pos = AD5259_MAX_POSITION; | ||
498 | err = sysfs_create_group(&dev->kobj, | ||
499 | &ad525x_group_wipers[AD525X_RDAC0]); | ||
500 | break; | ||
501 | case AD5251_ID: | ||
502 | data->max_pos = AD5251_MAX_POSITION; | ||
503 | err = sysfs_create_group(&dev->kobj, | ||
504 | &ad525x_group_wipers[AD525X_RDAC1]); | ||
505 | err |= sysfs_create_group(&dev->kobj, | ||
506 | &ad525x_group_wipers[AD525X_RDAC3]); | ||
507 | err |= sysfs_create_group(&dev->kobj, &ad525x_group_commands); | ||
508 | break; | ||
509 | case AD5252_ID: | ||
510 | data->max_pos = AD5252_MAX_POSITION; | ||
511 | err = sysfs_create_group(&dev->kobj, | ||
512 | &ad525x_group_wipers[AD525X_RDAC1]); | ||
513 | err |= sysfs_create_group(&dev->kobj, | ||
514 | &ad525x_group_wipers[AD525X_RDAC3]); | ||
515 | err |= sysfs_create_group(&dev->kobj, &ad525x_group_commands); | ||
516 | break; | ||
517 | case AD5253_ID: | ||
518 | data->max_pos = AD5253_MAX_POSITION; | ||
519 | err = sysfs_create_group(&dev->kobj, | ||
520 | &ad525x_group_wipers[AD525X_RDAC0]); | ||
521 | err |= sysfs_create_group(&dev->kobj, | ||
522 | &ad525x_group_wipers[AD525X_RDAC1]); | ||
523 | err |= sysfs_create_group(&dev->kobj, | ||
524 | &ad525x_group_wipers[AD525X_RDAC2]); | ||
525 | err |= sysfs_create_group(&dev->kobj, | ||
526 | &ad525x_group_wipers[AD525X_RDAC3]); | ||
527 | err |= sysfs_create_group(&dev->kobj, &ad525x_group_commands); | ||
528 | break; | ||
529 | case AD5254_ID: | ||
530 | data->max_pos = AD5254_MAX_POSITION; | ||
531 | err = sysfs_create_group(&dev->kobj, | ||
532 | &ad525x_group_wipers[AD525X_RDAC0]); | ||
533 | err |= sysfs_create_group(&dev->kobj, | ||
534 | &ad525x_group_wipers[AD525X_RDAC1]); | ||
535 | err |= sysfs_create_group(&dev->kobj, | ||
536 | &ad525x_group_wipers[AD525X_RDAC2]); | ||
537 | err |= sysfs_create_group(&dev->kobj, | ||
538 | &ad525x_group_wipers[AD525X_RDAC3]); | ||
539 | err |= sysfs_create_group(&dev->kobj, &ad525x_group_commands); | ||
540 | break; | ||
541 | case AD5255_ID: | ||
542 | data->max_pos = AD5255_MAX_POSITION; | ||
543 | err = sysfs_create_group(&dev->kobj, | ||
544 | &ad525x_group_wipers[AD525X_RDAC0]); | ||
545 | err |= sysfs_create_group(&dev->kobj, | ||
546 | &ad525x_group_wipers[AD525X_RDAC1]); | ||
547 | err |= sysfs_create_group(&dev->kobj, | ||
548 | &ad525x_group_wipers[AD525X_RDAC2]); | ||
549 | err |= sysfs_create_group(&dev->kobj, &ad525x_group_commands); | ||
550 | break; | ||
551 | default: | ||
552 | err = -ENODEV; | ||
553 | goto exit_free; | ||
554 | } | ||
555 | |||
556 | if (err) { | ||
557 | dev_err(dev, "failed to register sysfs hooks\n"); | ||
558 | goto exit_free; | ||
559 | } | ||
560 | |||
561 | data->devid = id->driver_data; | ||
562 | data->rdac_mask = data->max_pos - 1; | ||
563 | |||
564 | dev_info(dev, "%s %d-Position Digital Potentiometer registered\n", | ||
565 | id->name, data->max_pos); | ||
566 | |||
567 | return 0; | ||
568 | |||
569 | exit_free: | ||
570 | kfree(data); | ||
571 | i2c_set_clientdata(client, NULL); | ||
572 | exit: | ||
573 | dev_err(dev, "failed to create client\n"); | ||
574 | return err; | ||
575 | } | ||
576 | |||
577 | static int __devexit ad525x_remove(struct i2c_client *client) | ||
578 | { | ||
579 | struct dpot_data *data = i2c_get_clientdata(client); | ||
580 | struct device *dev = &client->dev; | ||
581 | |||
582 | switch (data->devid) { | ||
583 | case AD5258_ID: | ||
584 | case AD5259_ID: | ||
585 | sysfs_remove_group(&dev->kobj, | ||
586 | &ad525x_group_wipers[AD525X_RDAC0]); | ||
587 | break; | ||
588 | case AD5251_ID: | ||
589 | case AD5252_ID: | ||
590 | sysfs_remove_group(&dev->kobj, | ||
591 | &ad525x_group_wipers[AD525X_RDAC1]); | ||
592 | sysfs_remove_group(&dev->kobj, | ||
593 | &ad525x_group_wipers[AD525X_RDAC3]); | ||
594 | sysfs_remove_group(&dev->kobj, &ad525x_group_commands); | ||
595 | break; | ||
596 | case AD5253_ID: | ||
597 | case AD5254_ID: | ||
598 | sysfs_remove_group(&dev->kobj, | ||
599 | &ad525x_group_wipers[AD525X_RDAC0]); | ||
600 | sysfs_remove_group(&dev->kobj, | ||
601 | &ad525x_group_wipers[AD525X_RDAC1]); | ||
602 | sysfs_remove_group(&dev->kobj, | ||
603 | &ad525x_group_wipers[AD525X_RDAC2]); | ||
604 | sysfs_remove_group(&dev->kobj, | ||
605 | &ad525x_group_wipers[AD525X_RDAC3]); | ||
606 | sysfs_remove_group(&dev->kobj, &ad525x_group_commands); | ||
607 | break; | ||
608 | case AD5255_ID: | ||
609 | sysfs_remove_group(&dev->kobj, | ||
610 | &ad525x_group_wipers[AD525X_RDAC0]); | ||
611 | sysfs_remove_group(&dev->kobj, | ||
612 | &ad525x_group_wipers[AD525X_RDAC1]); | ||
613 | sysfs_remove_group(&dev->kobj, | ||
614 | &ad525x_group_wipers[AD525X_RDAC2]); | ||
615 | sysfs_remove_group(&dev->kobj, &ad525x_group_commands); | ||
616 | break; | ||
617 | } | ||
618 | |||
619 | i2c_set_clientdata(client, NULL); | ||
620 | kfree(data); | ||
621 | |||
622 | return 0; | ||
623 | } | ||
624 | |||
625 | static const struct i2c_device_id ad525x_idtable[] = { | ||
626 | {"ad5258", AD5258_ID}, | ||
627 | {"ad5259", AD5259_ID}, | ||
628 | {"ad5251", AD5251_ID}, | ||
629 | {"ad5252", AD5252_ID}, | ||
630 | {"ad5253", AD5253_ID}, | ||
631 | {"ad5254", AD5254_ID}, | ||
632 | {"ad5255", AD5255_ID}, | ||
633 | {} | ||
634 | }; | ||
635 | |||
636 | MODULE_DEVICE_TABLE(i2c, ad525x_idtable); | ||
637 | |||
638 | static struct i2c_driver ad525x_driver = { | ||
639 | .driver = { | ||
640 | .owner = THIS_MODULE, | ||
641 | .name = DRIVER_NAME, | ||
642 | }, | ||
643 | .id_table = ad525x_idtable, | ||
644 | .probe = ad525x_probe, | ||
645 | .remove = __devexit_p(ad525x_remove), | ||
646 | }; | ||
647 | |||
648 | static int __init ad525x_init(void) | ||
649 | { | ||
650 | return i2c_add_driver(&ad525x_driver); | ||
651 | } | ||
652 | |||
653 | module_init(ad525x_init); | ||
654 | |||
655 | static void __exit ad525x_exit(void) | ||
656 | { | ||
657 | i2c_del_driver(&ad525x_driver); | ||
658 | } | ||
659 | |||
660 | module_exit(ad525x_exit); | ||
661 | |||
662 | MODULE_AUTHOR("Chris Verges <chrisv@cyberswitching.com>, " | ||
663 | "Michael Hennerich <hennerich@blackfin.uclinux.org>, "); | ||
664 | MODULE_DESCRIPTION("AD5258/9 digital potentiometer driver"); | ||
665 | MODULE_LICENSE("GPL"); | ||
666 | MODULE_VERSION(DRIVER_VERSION); | ||