1/*
2 * Windfarm PowerMac thermal control. SMU based controls
3 *
4 * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
5 *                    <benh@kernel.crashing.org>
6 *
7 * Released under the term of the GNU GPL v2.
8 */
9
10#include <linux/types.h>
11#include <linux/errno.h>
12#include <linux/kernel.h>
13#include <linux/delay.h>
14#include <linux/slab.h>
15#include <linux/init.h>
16#include <linux/wait.h>
17#include <linux/completion.h>
18#include <asm/prom.h>
19#include <asm/machdep.h>
20#include <asm/io.h>
21#include <asm/sections.h>
22#include <asm/smu.h>
23
24#include "windfarm.h"
25
26#define VERSION "0.4"
27
28#undef DEBUG
29
30#ifdef DEBUG
31#define DBG(args...)	printk(args)
32#else
33#define DBG(args...)	do { } while(0)
34#endif
35
36static int smu_supports_new_fans_ops = 1;
37
38/*
39 * SMU fans control object
40 */
41
42static LIST_HEAD(smu_fans);
43
44struct smu_fan_control {
45	struct list_head	link;
46	int    			fan_type;	/* 0 = rpm, 1 = pwm */
47	u32			reg;		/* index in SMU */
48	s32			value;		/* current value */
49	s32			min, max;	/* min/max values */
50	struct wf_control	ctrl;
51};
52#define to_smu_fan(c) container_of(c, struct smu_fan_control, ctrl)
53
54static int smu_set_fan(int pwm, u8 id, u16 value)
55{
56	struct smu_cmd cmd;
57	u8 buffer[16];
58	DECLARE_COMPLETION_ONSTACK(comp);
59	int rc;
60
61	/* Fill SMU command structure */
62	cmd.cmd = SMU_CMD_FAN_COMMAND;
63
64	/* The SMU has an "old" and a "new" way of setting the fan speed
65	 * Unfortunately, I found no reliable way to know which one works
66	 * on a given machine model. After some investigations it appears
67	 * that MacOS X just tries the new one, and if it fails fallbacks
68	 * to the old ones ... Ugh.
69	 */
70 retry:
71	if (smu_supports_new_fans_ops) {
72		buffer[0] = 0x30;
73		buffer[1] = id;
74		*((u16 *)(&buffer[2])) = value;
75		cmd.data_len = 4;
76	} else {
77		if (id > 7)
78			return -EINVAL;
79		/* Fill argument buffer */
80		memset(buffer, 0, 16);
81		buffer[0] = pwm ? 0x10 : 0x00;
82		buffer[1] = 0x01 << id;
83		*((u16 *)&buffer[2 + id * 2]) = value;
84		cmd.data_len = 14;
85	}
86
87	cmd.reply_len = 16;
88	cmd.data_buf = cmd.reply_buf = buffer;
89	cmd.status = 0;
90	cmd.done = smu_done_complete;
91	cmd.misc = &comp;
92
93	rc = smu_queue_cmd(&cmd);
94	if (rc)
95		return rc;
96	wait_for_completion(&comp);
97
98	/* Handle fallback (see coment above) */
99	if (cmd.status != 0 && smu_supports_new_fans_ops) {
100		printk(KERN_WARNING "windfarm: SMU failed new fan command "
101		       "falling back to old method\n");
102		smu_supports_new_fans_ops = 0;
103		goto retry;
104	}
105
106	return cmd.status;
107}
108
109static void smu_fan_release(struct wf_control *ct)
110{
111	struct smu_fan_control *fct = to_smu_fan(ct);
112
113	kfree(fct);
114}
115
116static int smu_fan_set(struct wf_control *ct, s32 value)
117{
118	struct smu_fan_control *fct = to_smu_fan(ct);
119
120	if (value < fct->min)
121		value = fct->min;
122	if (value > fct->max)
123		value = fct->max;
124	fct->value = value;
125
126	return smu_set_fan(fct->fan_type, fct->reg, value);
127}
128
129static int smu_fan_get(struct wf_control *ct, s32 *value)
130{
131	struct smu_fan_control *fct = to_smu_fan(ct);
132	*value = fct->value; /* todo: read from SMU */
133	return 0;
134}
135
136static s32 smu_fan_min(struct wf_control *ct)
137{
138	struct smu_fan_control *fct = to_smu_fan(ct);
139	return fct->min;
140}
141
142static s32 smu_fan_max(struct wf_control *ct)
143{
144	struct smu_fan_control *fct = to_smu_fan(ct);
145	return fct->max;
146}
147
148static struct wf_control_ops smu_fan_ops = {
149	.set_value	= smu_fan_set,
150	.get_value	= smu_fan_get,
151	.get_min	= smu_fan_min,
152	.get_max	= smu_fan_max,
153	.release	= smu_fan_release,
154	.owner		= THIS_MODULE,
155};
156
157static struct smu_fan_control *smu_fan_create(struct device_node *node,
158					      int pwm_fan)
159{
160	struct smu_fan_control *fct;
161	const s32 *v;
162	const u32 *reg;
163	const char *l;
164
165	fct = kmalloc(sizeof(struct smu_fan_control), GFP_KERNEL);
166	if (fct == NULL)
167		return NULL;
168	fct->ctrl.ops = &smu_fan_ops;
169	l = of_get_property(node, "location", NULL);
170	if (l == NULL)
171		goto fail;
172
173	fct->fan_type = pwm_fan;
174	fct->ctrl.type = pwm_fan ? WF_CONTROL_PWM_FAN : WF_CONTROL_RPM_FAN;
175
176	/* We use the name & location here the same way we do for SMU sensors,
177	 * see the comment in windfarm_smu_sensors.c. The locations are a bit
178	 * less consistent here between the iMac and the desktop models, but
179	 * that is good enough for our needs for now at least.
180	 *
181	 * One problem though is that Apple seem to be inconsistent with case
182	 * and the kernel doesn't have strcasecmp =P
183	 */
184
185	fct->ctrl.name = NULL;
186
187	/* Names used on desktop models */
188	if (!strcmp(l, "Rear Fan 0") || !strcmp(l, "Rear Fan") ||
189	    !strcmp(l, "Rear fan 0") || !strcmp(l, "Rear fan") ||
190	    !strcmp(l, "CPU A EXHAUST"))
191		fct->ctrl.name = "cpu-rear-fan-0";
192	else if (!strcmp(l, "Rear Fan 1") || !strcmp(l, "Rear fan 1") ||
193		 !strcmp(l, "CPU B EXHAUST"))
194		fct->ctrl.name = "cpu-rear-fan-1";
195	else if (!strcmp(l, "Front Fan 0") || !strcmp(l, "Front Fan") ||
196		 !strcmp(l, "Front fan 0") || !strcmp(l, "Front fan") ||
197		 !strcmp(l, "CPU A INTAKE"))
198		fct->ctrl.name = "cpu-front-fan-0";
199	else if (!strcmp(l, "Front Fan 1") || !strcmp(l, "Front fan 1") ||
200		 !strcmp(l, "CPU B INTAKE"))
201		fct->ctrl.name = "cpu-front-fan-1";
202	else if (!strcmp(l, "CPU A PUMP"))
203		fct->ctrl.name = "cpu-pump-0";
204	else if (!strcmp(l, "CPU B PUMP"))
205		fct->ctrl.name = "cpu-pump-1";
206	else if (!strcmp(l, "Slots Fan") || !strcmp(l, "Slots fan") ||
207		 !strcmp(l, "EXPANSION SLOTS INTAKE"))
208		fct->ctrl.name = "slots-fan";
209	else if (!strcmp(l, "Drive Bay") || !strcmp(l, "Drive bay") ||
210		 !strcmp(l, "DRIVE BAY A INTAKE"))
211		fct->ctrl.name = "drive-bay-fan";
212	else if (!strcmp(l, "BACKSIDE"))
213		fct->ctrl.name = "backside-fan";
214
215	/* Names used on iMac models */
216	if (!strcmp(l, "System Fan") || !strcmp(l, "System fan"))
217		fct->ctrl.name = "system-fan";
218	else if (!strcmp(l, "CPU Fan") || !strcmp(l, "CPU fan"))
219		fct->ctrl.name = "cpu-fan";
220	else if (!strcmp(l, "Hard Drive") || !strcmp(l, "Hard drive"))
221		fct->ctrl.name = "drive-bay-fan";
222	else if (!strcmp(l, "HDD Fan")) /* seen on iMac G5 iSight */
223		fct->ctrl.name = "hard-drive-fan";
224	else if (!strcmp(l, "ODD Fan")) /* same */
225		fct->ctrl.name = "optical-drive-fan";
226
227	/* Unrecognized fan, bail out */
228	if (fct->ctrl.name == NULL)
229		goto fail;
230
231	/* Get min & max values*/
232	v = of_get_property(node, "min-value", NULL);
233	if (v == NULL)
234		goto fail;
235	fct->min = *v;
236	v = of_get_property(node, "max-value", NULL);
237	if (v == NULL)
238		goto fail;
239	fct->max = *v;
240
241	/* Get "reg" value */
242	reg = of_get_property(node, "reg", NULL);
243	if (reg == NULL)
244		goto fail;
245	fct->reg = *reg;
246
247	if (wf_register_control(&fct->ctrl))
248		goto fail;
249
250	return fct;
251 fail:
252	kfree(fct);
253	return NULL;
254}
255
256
257static int __init smu_controls_init(void)
258{
259	struct device_node *smu, *fans, *fan;
260
261	if (!smu_present())
262		return -ENODEV;
263
264	smu = of_find_node_by_type(NULL, "smu");
265	if (smu == NULL)
266		return -ENODEV;
267
268	/* Look for RPM fans */
269	for (fans = NULL; (fans = of_get_next_child(smu, fans)) != NULL;)
270		if (!strcmp(fans->name, "rpm-fans") ||
271		    of_device_is_compatible(fans, "smu-rpm-fans"))
272			break;
273	for (fan = NULL;
274	     fans && (fan = of_get_next_child(fans, fan)) != NULL;) {
275		struct smu_fan_control *fct;
276
277		fct = smu_fan_create(fan, 0);
278		if (fct == NULL) {
279			printk(KERN_WARNING "windfarm: Failed to create SMU "
280			       "RPM fan %s\n", fan->name);
281			continue;
282		}
283		list_add(&fct->link, &smu_fans);
284	}
285	of_node_put(fans);
286
287
288	/* Look for PWM fans */
289	for (fans = NULL; (fans = of_get_next_child(smu, fans)) != NULL;)
290		if (!strcmp(fans->name, "pwm-fans"))
291			break;
292	for (fan = NULL;
293	     fans && (fan = of_get_next_child(fans, fan)) != NULL;) {
294		struct smu_fan_control *fct;
295
296		fct = smu_fan_create(fan, 1);
297		if (fct == NULL) {
298			printk(KERN_WARNING "windfarm: Failed to create SMU "
299			       "PWM fan %s\n", fan->name);
300			continue;
301		}
302		list_add(&fct->link, &smu_fans);
303	}
304	of_node_put(fans);
305	of_node_put(smu);
306
307	return 0;
308}
309
310static void __exit smu_controls_exit(void)
311{
312	struct smu_fan_control *fct;
313
314	while (!list_empty(&smu_fans)) {
315		fct = list_entry(smu_fans.next, struct smu_fan_control, link);
316		list_del(&fct->link);
317		wf_unregister_control(&fct->ctrl);
318	}
319}
320
321
322module_init(smu_controls_init);
323module_exit(smu_controls_exit);
324
325MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
326MODULE_DESCRIPTION("SMU control objects for PowerMacs thermal control");
327MODULE_LICENSE("GPL");
328
329