xref: /linux/drivers/macintosh/windfarm_smu_controls.c (revision de25968cc87cc5b76d09de8b4cbddc8f24fcf5f7)
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/system.h>
22 #include <asm/sections.h>
23 #include <asm/smu.h>
24 
25 #include "windfarm.h"
26 
27 #define VERSION "0.3"
28 
29 #undef DEBUG
30 
31 #ifdef DEBUG
32 #define DBG(args...)	printk(args)
33 #else
34 #define DBG(args...)	do { } while(0)
35 #endif
36 
37 /*
38  * SMU fans control object
39  */
40 
41 static LIST_HEAD(smu_fans);
42 
43 struct smu_fan_control {
44 	struct list_head	link;
45 	int    			fan_type;	/* 0 = rpm, 1 = pwm */
46 	u32			reg;		/* index in SMU */
47 	s32			value;		/* current value */
48 	s32			min, max;	/* min/max values */
49 	struct wf_control	ctrl;
50 };
51 #define to_smu_fan(c) container_of(c, struct smu_fan_control, ctrl)
52 
53 static int smu_set_fan(int pwm, u8 id, u16 value)
54 {
55 	struct smu_cmd cmd;
56 	u8 buffer[16];
57 	DECLARE_COMPLETION(comp);
58 	int rc;
59 
60 	/* Fill SMU command structure */
61 	cmd.cmd = SMU_CMD_FAN_COMMAND;
62 	cmd.data_len = 14;
63 	cmd.reply_len = 16;
64 	cmd.data_buf = cmd.reply_buf = buffer;
65 	cmd.status = 0;
66 	cmd.done = smu_done_complete;
67 	cmd.misc = &comp;
68 
69 	/* Fill argument buffer */
70 	memset(buffer, 0, 16);
71 	buffer[0] = pwm ? 0x10 : 0x00;
72 	buffer[1] = 0x01 << id;
73 	*((u16 *)&buffer[2 + id * 2]) = value;
74 
75 	rc = smu_queue_cmd(&cmd);
76 	if (rc)
77 		return rc;
78 	wait_for_completion(&comp);
79 	return cmd.status;
80 }
81 
82 static void smu_fan_release(struct wf_control *ct)
83 {
84 	struct smu_fan_control *fct = to_smu_fan(ct);
85 
86 	kfree(fct);
87 }
88 
89 static int smu_fan_set(struct wf_control *ct, s32 value)
90 {
91 	struct smu_fan_control *fct = to_smu_fan(ct);
92 
93 	if (value < fct->min)
94 		value = fct->min;
95 	if (value > fct->max)
96 		value = fct->max;
97 	fct->value = value;
98 
99 	return smu_set_fan(fct->fan_type, fct->reg, value);
100 }
101 
102 static int smu_fan_get(struct wf_control *ct, s32 *value)
103 {
104 	struct smu_fan_control *fct = to_smu_fan(ct);
105 	*value = fct->value; /* todo: read from SMU */
106 	return 0;
107 }
108 
109 static s32 smu_fan_min(struct wf_control *ct)
110 {
111 	struct smu_fan_control *fct = to_smu_fan(ct);
112 	return fct->min;
113 }
114 
115 static s32 smu_fan_max(struct wf_control *ct)
116 {
117 	struct smu_fan_control *fct = to_smu_fan(ct);
118 	return fct->max;
119 }
120 
121 static struct wf_control_ops smu_fan_ops = {
122 	.set_value	= smu_fan_set,
123 	.get_value	= smu_fan_get,
124 	.get_min	= smu_fan_min,
125 	.get_max	= smu_fan_max,
126 	.release	= smu_fan_release,
127 	.owner		= THIS_MODULE,
128 };
129 
130 static struct smu_fan_control *smu_fan_create(struct device_node *node,
131 					      int pwm_fan)
132 {
133 	struct smu_fan_control *fct;
134 	s32 *v; u32 *reg;
135 	char *l;
136 
137 	fct = kmalloc(sizeof(struct smu_fan_control), GFP_KERNEL);
138 	if (fct == NULL)
139 		return NULL;
140 	fct->ctrl.ops = &smu_fan_ops;
141 	l = (char *)get_property(node, "location", NULL);
142 	if (l == NULL)
143 		goto fail;
144 
145 	fct->fan_type = pwm_fan;
146 	fct->ctrl.type = pwm_fan ? WF_CONTROL_PWM_FAN : WF_CONTROL_RPM_FAN;
147 
148 	/* We use the name & location here the same way we do for SMU sensors,
149 	 * see the comment in windfarm_smu_sensors.c. The locations are a bit
150 	 * less consistent here between the iMac and the desktop models, but
151 	 * that is good enough for our needs for now at least.
152 	 *
153 	 * One problem though is that Apple seem to be inconsistent with case
154 	 * and the kernel doesn't have strcasecmp =P
155 	 */
156 
157 	fct->ctrl.name = NULL;
158 
159 	/* Names used on desktop models */
160 	if (!strcmp(l, "Rear Fan 0") || !strcmp(l, "Rear Fan") ||
161 	    !strcmp(l, "Rear fan 0") || !strcmp(l, "Rear fan"))
162 		fct->ctrl.name = "cpu-rear-fan-0";
163 	else if (!strcmp(l, "Rear Fan 1") || !strcmp(l, "Rear fan 1"))
164 		fct->ctrl.name = "cpu-rear-fan-1";
165 	else if (!strcmp(l, "Front Fan 0") || !strcmp(l, "Front Fan") ||
166 		 !strcmp(l, "Front fan 0") || !strcmp(l, "Front fan"))
167 		fct->ctrl.name = "cpu-front-fan-0";
168 	else if (!strcmp(l, "Front Fan 1") || !strcmp(l, "Front fan 1"))
169 		fct->ctrl.name = "cpu-front-fan-1";
170 	else if (!strcmp(l, "Slots Fan") || !strcmp(l, "Slots fan"))
171 		fct->ctrl.name = "slots-fan";
172 	else if (!strcmp(l, "Drive Bay") || !strcmp(l, "Drive bay"))
173 		fct->ctrl.name = "drive-bay-fan";
174 
175 	/* Names used on iMac models */
176 	if (!strcmp(l, "System Fan") || !strcmp(l, "System fan"))
177 		fct->ctrl.name = "system-fan";
178 	else if (!strcmp(l, "CPU Fan") || !strcmp(l, "CPU fan"))
179 		fct->ctrl.name = "cpu-fan";
180 	else if (!strcmp(l, "Hard Drive") || !strcmp(l, "Hard drive"))
181 		fct->ctrl.name = "drive-bay-fan";
182 
183 	/* Unrecognized fan, bail out */
184 	if (fct->ctrl.name == NULL)
185 		goto fail;
186 
187 	/* Get min & max values*/
188 	v = (s32 *)get_property(node, "min-value", NULL);
189 	if (v == NULL)
190 		goto fail;
191 	fct->min = *v;
192 	v = (s32 *)get_property(node, "max-value", NULL);
193 	if (v == NULL)
194 		goto fail;
195 	fct->max = *v;
196 
197 	/* Get "reg" value */
198 	reg = (u32 *)get_property(node, "reg", NULL);
199 	if (reg == NULL)
200 		goto fail;
201 	fct->reg = *reg;
202 
203 	if (wf_register_control(&fct->ctrl))
204 		goto fail;
205 
206 	return fct;
207  fail:
208 	kfree(fct);
209 	return NULL;
210 }
211 
212 
213 static int __init smu_controls_init(void)
214 {
215 	struct device_node *smu, *fans, *fan;
216 
217 	if (!smu_present())
218 		return -ENODEV;
219 
220 	smu = of_find_node_by_type(NULL, "smu");
221 	if (smu == NULL)
222 		return -ENODEV;
223 
224 	/* Look for RPM fans */
225 	for (fans = NULL; (fans = of_get_next_child(smu, fans)) != NULL;)
226 		if (!strcmp(fans->name, "rpm-fans"))
227 			break;
228 	for (fan = NULL;
229 	     fans && (fan = of_get_next_child(fans, fan)) != NULL;) {
230 		struct smu_fan_control *fct;
231 
232 		fct = smu_fan_create(fan, 0);
233 		if (fct == NULL) {
234 			printk(KERN_WARNING "windfarm: Failed to create SMU "
235 			       "RPM fan %s\n", fan->name);
236 			continue;
237 		}
238 		list_add(&fct->link, &smu_fans);
239 	}
240 	of_node_put(fans);
241 
242 
243 	/* Look for PWM fans */
244 	for (fans = NULL; (fans = of_get_next_child(smu, fans)) != NULL;)
245 		if (!strcmp(fans->name, "pwm-fans"))
246 			break;
247 	for (fan = NULL;
248 	     fans && (fan = of_get_next_child(fans, fan)) != NULL;) {
249 		struct smu_fan_control *fct;
250 
251 		fct = smu_fan_create(fan, 1);
252 		if (fct == NULL) {
253 			printk(KERN_WARNING "windfarm: Failed to create SMU "
254 			       "PWM fan %s\n", fan->name);
255 			continue;
256 		}
257 		list_add(&fct->link, &smu_fans);
258 	}
259 	of_node_put(fans);
260 	of_node_put(smu);
261 
262 	return 0;
263 }
264 
265 static void __exit smu_controls_exit(void)
266 {
267 	struct smu_fan_control *fct;
268 
269 	while (!list_empty(&smu_fans)) {
270 		fct = list_entry(smu_fans.next, struct smu_fan_control, link);
271 		list_del(&fct->link);
272 		wf_unregister_control(&fct->ctrl);
273 	}
274 }
275 
276 
277 module_init(smu_controls_init);
278 module_exit(smu_controls_exit);
279 
280 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
281 MODULE_DESCRIPTION("SMU control objects for PowerMacs thermal control");
282 MODULE_LICENSE("GPL");
283 
284