aboutsummaryrefslogtreecommitdiff
path: root/drivers/macintosh/windfarm_smu_sat.c
blob: 65a8ff3e1f8e8d4e1e73a7a7eda4bb9500fb9c82 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
/*
 * Windfarm PowerMac thermal control.  SMU "satellite" controller sensors.
 *
 * Copyright (C) 2005 Paul Mackerras, IBM Corp. <paulus@samba.org>
 *
 * Released under the terms of the GNU GPL v2.
 */

#include <linux/types.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/wait.h>
#include <linux/i2c.h>
#include <linux/mutex.h>
#include <asm/prom.h>
#include <asm/smu.h>
#include <asm/pmac_low_i2c.h>

#include "windfarm.h"

#define VERSION "0.2"

#define DEBUG

#ifdef DEBUG
#define DBG(args...)	printk(args)
#else
#define DBG(args...)	do { } while(0)
#endif

/* If the cache is older than 800ms we'll refetch it */
#define MAX_AGE		msecs_to_jiffies(800)

struct wf_sat {
	int			nr;
	atomic_t		refcnt;
	struct mutex		mutex;
	unsigned long		last_read; /* jiffies when cache last updated */
	u8			cache[16];
	struct i2c_client	*i2c;
	struct device_node	*node;
};

static struct wf_sat *sats[2];

struct wf_sat_sensor {
	int		index;
	int		index2;		/* used for power sensors */
	int		shift;
	struct wf_sat	*sat;
	struct wf_sensor sens;
};

#define wf_to_sat(c)	container_of(c, struct wf_sat_sensor, sens)

struct smu_sdbp_header *smu_sat_get_sdb_partition(unsigned int sat_id, int id,
						  unsigned int *size)
{
	struct wf_sat *sat;
	int err;
	unsigned int i, len;
	u8 *buf;
	u8 data[4];

	/* TODO: Add the resulting partition to the device-tree */

	if (sat_id > 1 || (sat = sats[sat_id]) == NULL)
		return NULL;

	err = i2c_smbus_write_word_data(sat->i2c, 8, id << 8);
	if (err) {
		printk(KERN_ERR "smu_sat_get_sdb_part wr error %d\n", err);
		return NULL;
	}

	err = i2c_smbus_read_word_data(sat->i2c, 9);
	if (err < 0) {
		printk(KERN_ERR "smu_sat_get_sdb_part rd len error\n");
		return NULL;
	}
	len = err;
	if (len == 0) {
		printk(KERN_ERR "smu_sat_get_sdb_part no partition %x\n", id);
		return NULL;
	}

	len = le16_to_cpu(len);
	len = (len + 3) & ~3;
	buf = kmalloc(len, GFP_KERNEL);
	if (buf == NULL)
		return NULL;

	for (i = 0; i < len; i += 4) {
		err = i2c_smbus_read_i2c_block_data(sat->i2c, 0xa, 4, data);
		if (err < 0) {
			printk(KERN_ERR "smu_sat_get_sdb_part rd err %d\n",
			       err);
			goto fail;
		}
		buf[i] = data[1];
		buf[i+1] = data[0];
		buf[i+2] = data[3];
		buf[i+3] = data[2];
	}
#ifdef DEBUG
	DBG(KERN_DEBUG "sat %d partition %x:", sat_id, id);
	for (i = 0; i < len; ++i)
		DBG(" %x", buf[i]);
	DBG("\n");
#endif

	if (size)
		*size = len;
	return (struct smu_sdbp_header *) buf;

 fail:
	kfree(buf);
	return NULL;
}
EXPORT_SYMBOL_GPL(smu_sat_get_sdb_partition);

/* refresh the cache */
static int wf_sat_read_cache(struct wf_sat *sat)
{
	int err;

	err = i2c_smbus_read_i2c_block_data(sat->i2c, 0x3f, 16, sat->cache);
	if (err < 0)
		return err;
	sat->last_read = jiffies;
#ifdef LOTSA_DEBUG
	{
		int i;
		DBG(KERN_DEBUG "wf_sat_get: data is");
		for (i = 0; i < 16; ++i)
			DBG(" %.2x", sat->cache[i]);
		DBG("\n");
	}
#endif
	return 0;
}

static int wf_sat_get(struct wf_sensor *sr, s32 *value)
{
	struct wf_sat_sensor *sens = wf_to_sat(sr);
	struct wf_sat *sat = sens->sat;
	int i, err;
	s32 val;

	if (sat->i2c == NULL)
		return -ENODEV;

	mutex_lock(&sat->mutex);
	if (time_after(jiffies, (sat->last_read + MAX_AGE))) {
		err = wf_sat_read_cache(sat);
		if (err)
			goto fail;
	}

	i = sens->index * 2;
	val = ((sat->cache[i] << 8) + sat->cache[i+1]) << sens->shift;
	if (sens->index2 >= 0) {
		i = sens->index2 * 2;
		/* 4.12 * 8.8 -> 12.20; shift right 4 to get 16.16 */
		val = (val * ((sat->cache[i] << 8) + sat->cache[i+1])) >> 4;
	}

	*value = val;
	err = 0;

 fail:
	mutex_unlock(&sat->mutex);
	return err;
}

static void wf_sat_release(struct wf_sensor *sr)
{
	struct wf_sat_sensor *sens = wf_to_sat(sr);
	struct wf_sat *sat = sens->sat;

	if (atomic_dec_and_test(&sat->refcnt)) {
		if (sat->nr >= 0)
			sats[sat->nr] = NULL;
		kfree(sat);
	}
	kfree(sens);
}

static struct wf_sensor_ops wf_sat_ops = {
	.get_value	= wf_sat_get,
	.release	= wf_sat_release,
	.owner		= THIS_MODULE,
};

static struct i2c_driver wf_sat_driver;

static void wf_sat_create(struct i2c_adapter *adapter, struct device_node *dev)
{
	struct i2c_board_info info;
	struct i2c_client *client;
	const u32 *reg;
	u8 addr;

	reg = of_get_property(dev, "reg", NULL);
	if (reg == NULL)
		return;
	addr = *reg;
	DBG(KERN_DEBUG "wf_sat: creating sat at address %x\n", addr);

	memset(&info, 0, sizeof(struct i2c_board_info));
	info.addr = (addr >> 1) & 0x7f;
	info.platform_data = dev;
	strlcpy(info.type, "wf_sat", I2C_NAME_SIZE);

	client = i2c_new_device(adapter, &info);
	if (client == NULL) {
		printk(KERN_ERR "windfarm: failed to attach smu-sat to i2c\n");
		return;
	}

	/*
	 * Let i2c-core delete that device on driver removal.
	 * This is safe because i2c-core holds the core_lock mutex for us.
	 */
	list_add_tail(&client->detected, &wf_sat_driver.clients);
}

static int wf_sat_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	struct device_node *dev = client->dev.platform_data;
	struct wf_sat *sat;
	struct wf_sat_sensor *sens;
	const u32 *reg;
	const char *loc, *type;
	u8 chip, core;
	struct device_node *child;
	int shift, cpu, index;
	char *name;
	int vsens[2], isens[2];

	sat = kzalloc(sizeof(struct wf_sat), GFP_KERNEL);
	if (sat == NULL)
		return -ENOMEM;
	sat->nr = -1;
	sat->node = of_node_get(dev);
	atomic_set(&sat->refcnt, 0);
	mutex_init(&sat->mutex);
	sat->i2c = client;
	i2c_set_clientdata(client, sat);

	vsens[0] = vsens[1] = -1;
	isens[0] = isens[1] = -1;
	child = NULL;
	while ((child = of_get_next_child(dev, child)) != NULL) {
		reg = of_get_property(child, "reg", NULL);
		type = of_get_property(child, "device_type", NULL);
		loc = of_get_property(child, "location", NULL);
		if (reg == NULL || loc == NULL)
			continue;

		/* the cooked sensors are between 0x30 and 0x37 */
		if (*reg < 0x30 || *reg > 0x37)
			continue;
		index = *reg - 0x30;

		/* expect location to be CPU [AB][01] ... */
		if (strncmp(loc, "CPU ", 4) != 0)
			continue;
		chip = loc[4] - 'A';
		core = loc[5] - '0';
		if (chip > 1 || core > 1) {
			printk(KERN_ERR "wf_sat_create: don't understand "
			       "location %s for %s\n", loc, child->full_name);
			continue;
		}
		cpu = 2 * chip + core;
		if (sat->nr < 0)
			sat->nr = chip;
		else if (sat->nr != chip) {
			printk(KERN_ERR "wf_sat_create: can't cope with "
			       "multiple CPU chips on one SAT (%s)\n", loc);
			continue;
		}

		if (strcmp(type, "voltage-sensor") == 0) {
			name = "cpu-voltage";
			shift = 4;
			vsens[core] = index;
		} else if (strcmp(type, "current-sensor") == 0) {
			name = "cpu-current";
			shift = 8;
			isens[core] = index;
		} else if (strcmp(type, "temp-sensor") == 0) {
			name = "cpu-temp";
			shift = 10;
		} else
			continue;	/* hmmm shouldn't happen */

		/* the +16 is enough for "cpu-voltage-n" */
		sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL);
		if (sens == NULL) {
			printk(KERN_ERR "wf_sat_create: couldn't create "
			       "%s sensor %d (no memory)\n", name, cpu);
			continue;
		}
		sens->index = index;
		sens->index2 = -1;
		sens->shift = shift;
		sens->sat = sat;
		atomic_inc(&sat->refcnt);
		sens->sens.ops = &wf_sat_ops;
		sens->sens.name = (char *) (sens + 1);
		snprintf(sens->sens.name, 16, "%s-%d", name, cpu);

		if (wf_register_sensor(&sens->sens)) {
			atomic_dec(&sat->refcnt);
			kfree(sens);
		}
	}

	/* make the power sensors */
	for (core = 0; core < 2; ++core) {
		if (vsens[core] < 0 || isens[core] < 0)
			continue;
		cpu = 2 * sat->nr + core;
		sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL);
		if (sens == NULL) {
			printk(KERN_ERR "wf_sat_create: couldn't create power "
			       "sensor %d (no memory)\n", cpu);
			continue;
		}
		sens->index = vsens[core];
		sens->index2 = isens[core];
		sens->shift = 0;
		sens->sat = sat;
		atomic_inc(&sat->refcnt);
		sens->sens.ops = &wf_sat_ops;
		sens->sens.name = (char *) (sens + 1);
		snprintf(sens->sens.name, 16, "cpu-power-%d", cpu);

		if (wf_register_sensor(&sens->sens)) {
			atomic_dec(&sat->refcnt);
			kfree(sens);
		}
	}

	if (sat->nr >= 0)
		sats[sat->nr] = sat;

	return 0;
}

static int wf_sat_attach(struct i2c_adapter *adapter)
{
	struct device_node *busnode, *dev = NULL;
	struct pmac_i2c_bus *bus;

	bus = pmac_i2c_adapter_to_bus(adapter);
	if (bus == NULL)
		return -ENODEV;
	busnode = pmac_i2c_get_bus_node(bus);

	while ((dev = of_get_next_child(busnode, dev)) != NULL)
		if (of_device_is_compatible(dev, "smu-sat"))
			wf_sat_create(adapter, dev);
	return 0;
}

static int wf_sat_remove(struct i2c_client *client)
{
	struct wf_sat *sat = i2c_get_clientdata(client);

	/* XXX TODO */

	sat->i2c = NULL;
	return 0;
}

static const struct i2c_device_id wf_sat_id[] = {
	{ "wf_sat", 0 },
	{ }
};

static struct i2c_driver wf_sat_driver = {
	.driver = {
		.name		= "wf_smu_sat",
	},
	.attach_adapter	= wf_sat_attach,
	.probe		= wf_sat_probe,
	.remove		= wf_sat_remove,
	.id_table	= wf_sat_id,
};

static int __init sat_sensors_init(void)
{
	return i2c_add_driver(&wf_sat_driver);
}

#if 0	/* uncomment when module_exit() below is uncommented */
static void __exit sat_sensors_exit(void)
{
	i2c_del_driver(&wf_sat_driver);
}
#endif

module_init(sat_sensors_init);
/*module_exit(sat_sensors_exit); Uncomment when cleanup is implemented */

MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
MODULE_DESCRIPTION("SMU satellite sensors for PowerMac thermal control");
MODULE_LICENSE("GPL");