LXR linux/drivers/macintosh/windfarm_smu

   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 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
 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