linux/drivers/macintosh/windfarm_smu_controls.c
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   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
  37static int smu_supports_new_fans_ops = 1;
  38
  39/*
  40 * SMU fans control object
  41 */
  42
  43static LIST_HEAD(smu_fans);
  44
  45struct 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
  55static 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
 110static 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
 117static 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
 130static 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
 137static 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
 143static 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
 149static 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
 158static 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
 256static 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
 309static 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
 321module_init(smu_controls_init);
 322module_exit(smu_controls_exit);
 323
 324MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
 325MODULE_DESCRIPTION("SMU control objects for PowerMacs thermal control");
 326MODULE_LICENSE("GPL");
 327
 328