drivers/macintosh/windfarm_smu_controls.c

   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
  36 static int smu_supports_new_fans_ops = 1;
  37
  38 /*
  39  * SMU fans control object
  40  */
  41
  42 static LIST_HEAD(smu_fans);
  43
  44 struct 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
  54 static 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
 109 static 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
 116 static 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
 129 static 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
 136 static 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
 142 static 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
 148 static const 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
 157 static 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
 257 static 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
 310 static 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
 322 module_init(smu_controls_init);
 323 module_exit(smu_controls_exit);
 324
 325 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
 326 MODULE_DESCRIPTION("SMU control objects for PowerMacs thermal control");
 327 MODULE_LICENSE("GPL");
 328