1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * A driver for the Integrated Circuits ICS932S401
4 * Copyright (C) 2008 IBM
5 *
6 * Author: Darrick J. Wong <darrick.wong@oracle.com>
7 */
8
9#include <linux/module.h>
10#include <linux/jiffies.h>
11#include <linux/i2c.h>
12#include <linux/err.h>
13#include <linux/mutex.h>
14#include <linux/delay.h>
15#include <linux/log2.h>
16#include <linux/slab.h>
17
18/* Addresses to scan */
19static const unsigned short normal_i2c[] = { 0x69, I2C_CLIENT_END };
20
21/* ICS932S401 registers */
22#define ICS932S401_REG_CFG2 0x01
23#define ICS932S401_CFG1_SPREAD 0x01
24#define ICS932S401_REG_CFG7 0x06
25#define ICS932S401_FS_MASK 0x07
26#define ICS932S401_REG_VENDOR_REV 0x07
27#define ICS932S401_VENDOR 1
28#define ICS932S401_VENDOR_MASK 0x0F
29#define ICS932S401_REV 4
30#define ICS932S401_REV_SHIFT 4
31#define ICS932S401_REG_DEVICE 0x09
32#define ICS932S401_DEVICE 11
33#define ICS932S401_REG_CTRL 0x0A
34#define ICS932S401_MN_ENABLED 0x80
35#define ICS932S401_CPU_ALT 0x04
36#define ICS932S401_SRC_ALT 0x08
37#define ICS932S401_REG_CPU_M_CTRL 0x0B
38#define ICS932S401_M_MASK 0x3F
39#define ICS932S401_REG_CPU_N_CTRL 0x0C
40#define ICS932S401_REG_CPU_SPREAD1 0x0D
41#define ICS932S401_REG_CPU_SPREAD2 0x0E
42#define ICS932S401_SPREAD_MASK 0x7FFF
43#define ICS932S401_REG_SRC_M_CTRL 0x0F
44#define ICS932S401_REG_SRC_N_CTRL 0x10
45#define ICS932S401_REG_SRC_SPREAD1 0x11
46#define ICS932S401_REG_SRC_SPREAD2 0x12
47#define ICS932S401_REG_CPU_DIVISOR 0x13
48#define ICS932S401_CPU_DIVISOR_SHIFT 4
49#define ICS932S401_REG_PCISRC_DIVISOR 0x14
50#define ICS932S401_SRC_DIVISOR_MASK 0x0F
51#define ICS932S401_PCI_DIVISOR_SHIFT 4
52
53/* Base clock is 14.318MHz */
54#define BASE_CLOCK 14318
55
56#define NUM_REGS 21
57#define NUM_MIRRORED_REGS 15
58
59static int regs_to_copy[NUM_MIRRORED_REGS] = {
60 ICS932S401_REG_CFG2,
61 ICS932S401_REG_CFG7,
62 ICS932S401_REG_VENDOR_REV,
63 ICS932S401_REG_DEVICE,
64 ICS932S401_REG_CTRL,
65 ICS932S401_REG_CPU_M_CTRL,
66 ICS932S401_REG_CPU_N_CTRL,
67 ICS932S401_REG_CPU_SPREAD1,
68 ICS932S401_REG_CPU_SPREAD2,
69 ICS932S401_REG_SRC_M_CTRL,
70 ICS932S401_REG_SRC_N_CTRL,
71 ICS932S401_REG_SRC_SPREAD1,
72 ICS932S401_REG_SRC_SPREAD2,
73 ICS932S401_REG_CPU_DIVISOR,
74 ICS932S401_REG_PCISRC_DIVISOR,
75};
76
77/* How often do we reread sensors values? (In jiffies) */
78#define SENSOR_REFRESH_INTERVAL (2 * HZ)
79
80/* How often do we reread sensor limit values? (In jiffies) */
81#define LIMIT_REFRESH_INTERVAL (60 * HZ)
82
83struct ics932s401_data {
84 struct attribute_group attrs;
85 struct mutex lock;
86 char sensors_valid;
87 unsigned long sensors_last_updated; /* In jiffies */
88
89 u8 regs[NUM_REGS];
90};
91
92static int ics932s401_probe(struct i2c_client *client);
93static int ics932s401_detect(struct i2c_client *client,
94 struct i2c_board_info *info);
95static void ics932s401_remove(struct i2c_client *client);
96
97static const struct i2c_device_id ics932s401_id[] = {
98 { "ics932s401", 0 },
99 { }
100};
101MODULE_DEVICE_TABLE(i2c, ics932s401_id);
102
103static struct i2c_driver ics932s401_driver = {
104 .class = I2C_CLASS_HWMON,
105 .driver = {
106 .name = "ics932s401",
107 },
108 .probe = ics932s401_probe,
109 .remove = ics932s401_remove,
110 .id_table = ics932s401_id,
111 .detect = ics932s401_detect,
112 .address_list = normal_i2c,
113};
114
115static struct ics932s401_data *ics932s401_update_device(struct device *dev)
116{
117 struct i2c_client *client = to_i2c_client(dev);
118 struct ics932s401_data *data = i2c_get_clientdata(client);
119 unsigned long local_jiffies = jiffies;
120 int i, temp;
121
122 mutex_lock(&data->lock);
123 if (time_before(local_jiffies, data->sensors_last_updated +
124 SENSOR_REFRESH_INTERVAL)
125 && data->sensors_valid)
126 goto out;
127
128 /*
129 * Each register must be read as a word and then right shifted 8 bits.
130 * Not really sure why this is; setting the "byte count programming"
131 * register to 1 does not fix this problem.
132 */
133 for (i = 0; i < NUM_MIRRORED_REGS; i++) {
134 temp = i2c_smbus_read_word_data(client, command: regs_to_copy[i]);
135 if (temp < 0)
136 temp = 0;
137 data->regs[regs_to_copy[i]] = temp >> 8;
138 }
139
140 data->sensors_last_updated = local_jiffies;
141 data->sensors_valid = 1;
142
143out:
144 mutex_unlock(lock: &data->lock);
145 return data;
146}
147
148static ssize_t show_spread_enabled(struct device *dev,
149 struct device_attribute *devattr,
150 char *buf)
151{
152 struct ics932s401_data *data = ics932s401_update_device(dev);
153
154 if (data->regs[ICS932S401_REG_CFG2] & ICS932S401_CFG1_SPREAD)
155 return sprintf(buf, fmt: "1\n");
156
157 return sprintf(buf, fmt: "0\n");
158}
159
160/* bit to cpu khz map */
161static const int fs_speeds[] = {
162 266666,
163 133333,
164 200000,
165 166666,
166 333333,
167 100000,
168 400000,
169 0,
170};
171
172/* clock divisor map */
173static const int divisors[] = {2, 3, 5, 15, 4, 6, 10, 30, 8, 12, 20, 60, 16,
174 24, 40, 120};
175
176/* Calculate CPU frequency from the M/N registers. */
177static int calculate_cpu_freq(struct ics932s401_data *data)
178{
179 int m, n, freq;
180
181 m = data->regs[ICS932S401_REG_CPU_M_CTRL] & ICS932S401_M_MASK;
182 n = data->regs[ICS932S401_REG_CPU_N_CTRL];
183
184 /* Pull in bits 8 & 9 from the M register */
185 n |= ((int)data->regs[ICS932S401_REG_CPU_M_CTRL] & 0x80) << 1;
186 n |= ((int)data->regs[ICS932S401_REG_CPU_M_CTRL] & 0x40) << 3;
187
188 freq = BASE_CLOCK * (n + 8) / (m + 2);
189 freq /= divisors[data->regs[ICS932S401_REG_CPU_DIVISOR] >>
190 ICS932S401_CPU_DIVISOR_SHIFT];
191
192 return freq;
193}
194
195static ssize_t show_cpu_clock(struct device *dev,
196 struct device_attribute *devattr,
197 char *buf)
198{
199 struct ics932s401_data *data = ics932s401_update_device(dev);
200
201 return sprintf(buf, fmt: "%d\n", calculate_cpu_freq(data));
202}
203
204static ssize_t show_cpu_clock_sel(struct device *dev,
205 struct device_attribute *devattr,
206 char *buf)
207{
208 struct ics932s401_data *data = ics932s401_update_device(dev);
209 int freq;
210
211 if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_MN_ENABLED)
212 freq = calculate_cpu_freq(data);
213 else {
214 /* Freq is neatly wrapped up for us */
215 int fid = data->regs[ICS932S401_REG_CFG7] & ICS932S401_FS_MASK;
216
217 freq = fs_speeds[fid];
218 if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_CPU_ALT) {
219 switch (freq) {
220 case 166666:
221 freq = 160000;
222 break;
223 case 333333:
224 freq = 320000;
225 break;
226 }
227 }
228 }
229
230 return sprintf(buf, fmt: "%d\n", freq);
231}
232
233/* Calculate SRC frequency from the M/N registers. */
234static int calculate_src_freq(struct ics932s401_data *data)
235{
236 int m, n, freq;
237
238 m = data->regs[ICS932S401_REG_SRC_M_CTRL] & ICS932S401_M_MASK;
239 n = data->regs[ICS932S401_REG_SRC_N_CTRL];
240
241 /* Pull in bits 8 & 9 from the M register */
242 n |= ((int)data->regs[ICS932S401_REG_SRC_M_CTRL] & 0x80) << 1;
243 n |= ((int)data->regs[ICS932S401_REG_SRC_M_CTRL] & 0x40) << 3;
244
245 freq = BASE_CLOCK * (n + 8) / (m + 2);
246 freq /= divisors[data->regs[ICS932S401_REG_PCISRC_DIVISOR] &
247 ICS932S401_SRC_DIVISOR_MASK];
248
249 return freq;
250}
251
252static ssize_t show_src_clock(struct device *dev,
253 struct device_attribute *devattr,
254 char *buf)
255{
256 struct ics932s401_data *data = ics932s401_update_device(dev);
257
258 return sprintf(buf, fmt: "%d\n", calculate_src_freq(data));
259}
260
261static ssize_t show_src_clock_sel(struct device *dev,
262 struct device_attribute *devattr,
263 char *buf)
264{
265 struct ics932s401_data *data = ics932s401_update_device(dev);
266 int freq;
267
268 if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_MN_ENABLED)
269 freq = calculate_src_freq(data);
270 else
271 /* Freq is neatly wrapped up for us */
272 if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_CPU_ALT &&
273 data->regs[ICS932S401_REG_CTRL] & ICS932S401_SRC_ALT)
274 freq = 96000;
275 else
276 freq = 100000;
277
278 return sprintf(buf, fmt: "%d\n", freq);
279}
280
281/* Calculate PCI frequency from the SRC M/N registers. */
282static int calculate_pci_freq(struct ics932s401_data *data)
283{
284 int m, n, freq;
285
286 m = data->regs[ICS932S401_REG_SRC_M_CTRL] & ICS932S401_M_MASK;
287 n = data->regs[ICS932S401_REG_SRC_N_CTRL];
288
289 /* Pull in bits 8 & 9 from the M register */
290 n |= ((int)data->regs[ICS932S401_REG_SRC_M_CTRL] & 0x80) << 1;
291 n |= ((int)data->regs[ICS932S401_REG_SRC_M_CTRL] & 0x40) << 3;
292
293 freq = BASE_CLOCK * (n + 8) / (m + 2);
294 freq /= divisors[data->regs[ICS932S401_REG_PCISRC_DIVISOR] >>
295 ICS932S401_PCI_DIVISOR_SHIFT];
296
297 return freq;
298}
299
300static ssize_t show_pci_clock(struct device *dev,
301 struct device_attribute *devattr,
302 char *buf)
303{
304 struct ics932s401_data *data = ics932s401_update_device(dev);
305
306 return sprintf(buf, fmt: "%d\n", calculate_pci_freq(data));
307}
308
309static ssize_t show_pci_clock_sel(struct device *dev,
310 struct device_attribute *devattr,
311 char *buf)
312{
313 struct ics932s401_data *data = ics932s401_update_device(dev);
314 int freq;
315
316 if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_MN_ENABLED)
317 freq = calculate_pci_freq(data);
318 else
319 freq = 33333;
320
321 return sprintf(buf, fmt: "%d\n", freq);
322}
323
324static ssize_t show_value(struct device *dev,
325 struct device_attribute *devattr,
326 char *buf);
327
328static ssize_t show_spread(struct device *dev,
329 struct device_attribute *devattr,
330 char *buf);
331
332static DEVICE_ATTR(spread_enabled, S_IRUGO, show_spread_enabled, NULL);
333static DEVICE_ATTR(cpu_clock_selection, S_IRUGO, show_cpu_clock_sel, NULL);
334static DEVICE_ATTR(cpu_clock, S_IRUGO, show_cpu_clock, NULL);
335static DEVICE_ATTR(src_clock_selection, S_IRUGO, show_src_clock_sel, NULL);
336static DEVICE_ATTR(src_clock, S_IRUGO, show_src_clock, NULL);
337static DEVICE_ATTR(pci_clock_selection, S_IRUGO, show_pci_clock_sel, NULL);
338static DEVICE_ATTR(pci_clock, S_IRUGO, show_pci_clock, NULL);
339static DEVICE_ATTR(usb_clock, S_IRUGO, show_value, NULL);
340static DEVICE_ATTR(ref_clock, S_IRUGO, show_value, NULL);
341static DEVICE_ATTR(cpu_spread, S_IRUGO, show_spread, NULL);
342static DEVICE_ATTR(src_spread, S_IRUGO, show_spread, NULL);
343
344static struct attribute *ics932s401_attr[] = {
345 &dev_attr_spread_enabled.attr,
346 &dev_attr_cpu_clock_selection.attr,
347 &dev_attr_cpu_clock.attr,
348 &dev_attr_src_clock_selection.attr,
349 &dev_attr_src_clock.attr,
350 &dev_attr_pci_clock_selection.attr,
351 &dev_attr_pci_clock.attr,
352 &dev_attr_usb_clock.attr,
353 &dev_attr_ref_clock.attr,
354 &dev_attr_cpu_spread.attr,
355 &dev_attr_src_spread.attr,
356 NULL
357};
358
359static ssize_t show_value(struct device *dev,
360 struct device_attribute *devattr,
361 char *buf)
362{
363 int x;
364
365 if (devattr == &dev_attr_usb_clock)
366 x = 48000;
367 else if (devattr == &dev_attr_ref_clock)
368 x = BASE_CLOCK;
369 else
370 BUG();
371
372 return sprintf(buf, fmt: "%d\n", x);
373}
374
375static ssize_t show_spread(struct device *dev,
376 struct device_attribute *devattr,
377 char *buf)
378{
379 struct ics932s401_data *data = ics932s401_update_device(dev);
380 int reg;
381 unsigned long val;
382
383 if (!(data->regs[ICS932S401_REG_CFG2] & ICS932S401_CFG1_SPREAD))
384 return sprintf(buf, fmt: "0%%\n");
385
386 if (devattr == &dev_attr_src_spread)
387 reg = ICS932S401_REG_SRC_SPREAD1;
388 else if (devattr == &dev_attr_cpu_spread)
389 reg = ICS932S401_REG_CPU_SPREAD1;
390 else
391 BUG();
392
393 val = data->regs[reg] | (data->regs[reg + 1] << 8);
394 val &= ICS932S401_SPREAD_MASK;
395
396 /* Scale 0..2^14 to -0.5. */
397 val = 500000 * val / 16384;
398 return sprintf(buf, fmt: "-0.%lu%%\n", val);
399}
400
401/* Return 0 if detection is successful, -ENODEV otherwise */
402static int ics932s401_detect(struct i2c_client *client,
403 struct i2c_board_info *info)
404{
405 struct i2c_adapter *adapter = client->adapter;
406 int vendor, device, revision;
407
408 if (!i2c_check_functionality(adap: adapter, I2C_FUNC_SMBUS_BYTE_DATA))
409 return -ENODEV;
410
411 vendor = i2c_smbus_read_word_data(client, ICS932S401_REG_VENDOR_REV);
412 vendor >>= 8;
413 revision = vendor >> ICS932S401_REV_SHIFT;
414 vendor &= ICS932S401_VENDOR_MASK;
415 if (vendor != ICS932S401_VENDOR)
416 return -ENODEV;
417
418 device = i2c_smbus_read_word_data(client, ICS932S401_REG_DEVICE);
419 device >>= 8;
420 if (device != ICS932S401_DEVICE)
421 return -ENODEV;
422
423 if (revision != ICS932S401_REV)
424 dev_info(&adapter->dev, "Unknown revision %d\n", revision);
425
426 strscpy(p: info->type, q: "ics932s401", I2C_NAME_SIZE);
427
428 return 0;
429}
430
431static int ics932s401_probe(struct i2c_client *client)
432{
433 struct ics932s401_data *data;
434 int err;
435
436 data = kzalloc(size: sizeof(struct ics932s401_data), GFP_KERNEL);
437 if (!data) {
438 err = -ENOMEM;
439 goto exit;
440 }
441
442 i2c_set_clientdata(client, data);
443 mutex_init(&data->lock);
444
445 dev_info(&client->dev, "%s chip found\n", client->name);
446
447 /* Register sysfs hooks */
448 data->attrs.attrs = ics932s401_attr;
449 err = sysfs_create_group(kobj: &client->dev.kobj, grp: &data->attrs);
450 if (err)
451 goto exit_free;
452
453 return 0;
454
455exit_free:
456 kfree(objp: data);
457exit:
458 return err;
459}
460
461static void ics932s401_remove(struct i2c_client *client)
462{
463 struct ics932s401_data *data = i2c_get_clientdata(client);
464
465 sysfs_remove_group(kobj: &client->dev.kobj, grp: &data->attrs);
466 kfree(objp: data);
467}
468
469module_i2c_driver(ics932s401_driver);
470
471MODULE_AUTHOR("Darrick J. Wong <darrick.wong@oracle.com>");
472MODULE_DESCRIPTION("ICS932S401 driver");
473MODULE_LICENSE("GPL");
474
475/* IBM IntelliStation Z30 */
476MODULE_ALIAS("dmi:bvnIBM:*:rn9228:*");
477MODULE_ALIAS("dmi:bvnIBM:*:rn9232:*");
478
479/* IBM x3650/x3550 */
480MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3650*");
481MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3550*");
482

source code of linux/drivers/misc/ics932s401.c