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