linux/drivers/macintosh/smu.c
<<
>>
Prefs
   1/*
   2 * PowerMac G5 SMU driver
   3 *
   4 * Copyright 2004 J. Mayer <l_indien@magic.fr>
   5 * Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
   6 *
   7 * Released under the term of the GNU GPL v2.
   8 */
   9
  10/*
  11 * TODO:
  12 *  - maybe add timeout to commands ?
  13 *  - blocking version of time functions
  14 *  - polling version of i2c commands (including timer that works with
  15 *    interrupts off)
  16 *  - maybe avoid some data copies with i2c by directly using the smu cmd
  17 *    buffer and a lower level internal interface
  18 *  - understand SMU -> CPU events and implement reception of them via
  19 *    the userland interface
  20 */
  21
  22#include <linux/types.h>
  23#include <linux/kernel.h>
  24#include <linux/device.h>
  25#include <linux/dmapool.h>
  26#include <linux/bootmem.h>
  27#include <linux/vmalloc.h>
  28#include <linux/highmem.h>
  29#include <linux/jiffies.h>
  30#include <linux/interrupt.h>
  31#include <linux/rtc.h>
  32#include <linux/completion.h>
  33#include <linux/miscdevice.h>
  34#include <linux/delay.h>
  35#include <linux/poll.h>
  36#include <linux/mutex.h>
  37#include <linux/of_device.h>
  38#include <linux/of_platform.h>
  39#include <linux/slab.h>
  40
  41#include <asm/byteorder.h>
  42#include <asm/io.h>
  43#include <asm/prom.h>
  44#include <asm/machdep.h>
  45#include <asm/pmac_feature.h>
  46#include <asm/smu.h>
  47#include <asm/sections.h>
  48#include <asm/abs_addr.h>
  49#include <asm/uaccess.h>
  50
  51#define VERSION "0.7"
  52#define AUTHOR  "(c) 2005 Benjamin Herrenschmidt, IBM Corp."
  53
  54#undef DEBUG_SMU
  55
  56#ifdef DEBUG_SMU
  57#define DPRINTK(fmt, args...) do { printk(KERN_DEBUG fmt , ##args); } while (0)
  58#else
  59#define DPRINTK(fmt, args...) do { } while (0)
  60#endif
  61
  62/*
  63 * This is the command buffer passed to the SMU hardware
  64 */
  65#define SMU_MAX_DATA    254
  66
  67struct smu_cmd_buf {
  68        u8 cmd;
  69        u8 length;
  70        u8 data[SMU_MAX_DATA];
  71};
  72
  73struct smu_device {
  74        spinlock_t              lock;
  75        struct device_node      *of_node;
  76        struct platform_device  *of_dev;
  77        int                     doorbell;       /* doorbell gpio */
  78        u32 __iomem             *db_buf;        /* doorbell buffer */
  79        struct device_node      *db_node;
  80        unsigned int            db_irq;
  81        int                     msg;
  82        struct device_node      *msg_node;
  83        unsigned int            msg_irq;
  84        struct smu_cmd_buf      *cmd_buf;       /* command buffer virtual */
  85        u32                     cmd_buf_abs;    /* command buffer absolute */
  86        struct list_head        cmd_list;
  87        struct smu_cmd          *cmd_cur;       /* pending command */
  88        int                     broken_nap;
  89        struct list_head        cmd_i2c_list;
  90        struct smu_i2c_cmd      *cmd_i2c_cur;   /* pending i2c command */
  91        struct timer_list       i2c_timer;
  92};
  93
  94/*
  95 * I don't think there will ever be more than one SMU, so
  96 * for now, just hard code that
  97 */
  98static DEFINE_MUTEX(smu_mutex);
  99static struct smu_device        *smu;
 100static DEFINE_MUTEX(smu_part_access);
 101static int smu_irq_inited;
 102
 103static void smu_i2c_retry(unsigned long data);
 104
 105/*
 106 * SMU driver low level stuff
 107 */
 108
 109static void smu_start_cmd(void)
 110{
 111        unsigned long faddr, fend;
 112        struct smu_cmd *cmd;
 113
 114        if (list_empty(&smu->cmd_list))
 115                return;
 116
 117        /* Fetch first command in queue */
 118        cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link);
 119        smu->cmd_cur = cmd;
 120        list_del(&cmd->link);
 121
 122        DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd,
 123                cmd->data_len);
 124        DPRINTK("SMU: data buffer: %02x %02x %02x %02x %02x %02x %02x %02x\n",
 125                ((u8 *)cmd->data_buf)[0], ((u8 *)cmd->data_buf)[1],
 126                ((u8 *)cmd->data_buf)[2], ((u8 *)cmd->data_buf)[3],
 127                ((u8 *)cmd->data_buf)[4], ((u8 *)cmd->data_buf)[5],
 128                ((u8 *)cmd->data_buf)[6], ((u8 *)cmd->data_buf)[7]);
 129
 130        /* Fill the SMU command buffer */
 131        smu->cmd_buf->cmd = cmd->cmd;
 132        smu->cmd_buf->length = cmd->data_len;
 133        memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len);
 134
 135        /* Flush command and data to RAM */
 136        faddr = (unsigned long)smu->cmd_buf;
 137        fend = faddr + smu->cmd_buf->length + 2;
 138        flush_inval_dcache_range(faddr, fend);
 139
 140
 141        /* We also disable NAP mode for the duration of the command
 142         * on U3 based machines.
 143         * This is slightly racy as it can be written back to 1 by a sysctl
 144         * but that never happens in practice. There seem to be an issue with
 145         * U3 based machines such as the iMac G5 where napping for the
 146         * whole duration of the command prevents the SMU from fetching it
 147         * from memory. This might be related to the strange i2c based
 148         * mechanism the SMU uses to access memory.
 149         */
 150        if (smu->broken_nap)
 151                powersave_nap = 0;
 152
 153        /* This isn't exactly a DMA mapping here, I suspect
 154         * the SMU is actually communicating with us via i2c to the
 155         * northbridge or the CPU to access RAM.
 156         */
 157        writel(smu->cmd_buf_abs, smu->db_buf);
 158
 159        /* Ring the SMU doorbell */
 160        pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4);
 161}
 162
 163
 164static irqreturn_t smu_db_intr(int irq, void *arg)
 165{
 166        unsigned long flags;
 167        struct smu_cmd *cmd;
 168        void (*done)(struct smu_cmd *cmd, void *misc) = NULL;
 169        void *misc = NULL;
 170        u8 gpio;
 171        int rc = 0;
 172
 173        /* SMU completed the command, well, we hope, let's make sure
 174         * of it
 175         */
 176        spin_lock_irqsave(&smu->lock, flags);
 177
 178        gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);
 179        if ((gpio & 7) != 7) {
 180                spin_unlock_irqrestore(&smu->lock, flags);
 181                return IRQ_HANDLED;
 182        }
 183
 184        cmd = smu->cmd_cur;
 185        smu->cmd_cur = NULL;
 186        if (cmd == NULL)
 187                goto bail;
 188
 189        if (rc == 0) {
 190                unsigned long faddr;
 191                int reply_len;
 192                u8 ack;
 193
 194                /* CPU might have brought back the cache line, so we need
 195                 * to flush again before peeking at the SMU response. We
 196                 * flush the entire buffer for now as we haven't read the
 197                 * reply length (it's only 2 cache lines anyway)
 198                 */
 199                faddr = (unsigned long)smu->cmd_buf;
 200                flush_inval_dcache_range(faddr, faddr + 256);
 201
 202                /* Now check ack */
 203                ack = (~cmd->cmd) & 0xff;
 204                if (ack != smu->cmd_buf->cmd) {
 205                        DPRINTK("SMU: incorrect ack, want %x got %x\n",
 206                                ack, smu->cmd_buf->cmd);
 207                        rc = -EIO;
 208                }
 209                reply_len = rc == 0 ? smu->cmd_buf->length : 0;
 210                DPRINTK("SMU: reply len: %d\n", reply_len);
 211                if (reply_len > cmd->reply_len) {
 212                        printk(KERN_WARNING "SMU: reply buffer too small,"
 213                               "got %d bytes for a %d bytes buffer\n",
 214                               reply_len, cmd->reply_len);
 215                        reply_len = cmd->reply_len;
 216                }
 217                cmd->reply_len = reply_len;
 218                if (cmd->reply_buf && reply_len)
 219                        memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len);
 220        }
 221
 222        /* Now complete the command. Write status last in order as we lost
 223         * ownership of the command structure as soon as it's no longer -1
 224         */
 225        done = cmd->done;
 226        misc = cmd->misc;
 227        mb();
 228        cmd->status = rc;
 229
 230        /* Re-enable NAP mode */
 231        if (smu->broken_nap)
 232                powersave_nap = 1;
 233 bail:
 234        /* Start next command if any */
 235        smu_start_cmd();
 236        spin_unlock_irqrestore(&smu->lock, flags);
 237
 238        /* Call command completion handler if any */
 239        if (done)
 240                done(cmd, misc);
 241
 242        /* It's an edge interrupt, nothing to do */
 243        return IRQ_HANDLED;
 244}
 245
 246
 247static irqreturn_t smu_msg_intr(int irq, void *arg)
 248{
 249        /* I don't quite know what to do with this one, we seem to never
 250         * receive it, so I suspect we have to arm it someway in the SMU
 251         * to start getting events that way.
 252         */
 253
 254        printk(KERN_INFO "SMU: message interrupt !\n");
 255
 256        /* It's an edge interrupt, nothing to do */
 257        return IRQ_HANDLED;
 258}
 259
 260
 261/*
 262 * Queued command management.
 263 *
 264 */
 265
 266int smu_queue_cmd(struct smu_cmd *cmd)
 267{
 268        unsigned long flags;
 269
 270        if (smu == NULL)
 271                return -ENODEV;
 272        if (cmd->data_len > SMU_MAX_DATA ||
 273            cmd->reply_len > SMU_MAX_DATA)
 274                return -EINVAL;
 275
 276        cmd->status = 1;
 277        spin_lock_irqsave(&smu->lock, flags);
 278        list_add_tail(&cmd->link, &smu->cmd_list);
 279        if (smu->cmd_cur == NULL)
 280                smu_start_cmd();
 281        spin_unlock_irqrestore(&smu->lock, flags);
 282
 283        /* Workaround for early calls when irq isn't available */
 284        if (!smu_irq_inited || smu->db_irq == NO_IRQ)
 285                smu_spinwait_cmd(cmd);
 286
 287        return 0;
 288}
 289EXPORT_SYMBOL(smu_queue_cmd);
 290
 291
 292int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command,
 293                     unsigned int data_len,
 294                     void (*done)(struct smu_cmd *cmd, void *misc),
 295                     void *misc, ...)
 296{
 297        struct smu_cmd *cmd = &scmd->cmd;
 298        va_list list;
 299        int i;
 300
 301        if (data_len > sizeof(scmd->buffer))
 302                return -EINVAL;
 303
 304        memset(scmd, 0, sizeof(*scmd));
 305        cmd->cmd = command;
 306        cmd->data_len = data_len;
 307        cmd->data_buf = scmd->buffer;
 308        cmd->reply_len = sizeof(scmd->buffer);
 309        cmd->reply_buf = scmd->buffer;
 310        cmd->done = done;
 311        cmd->misc = misc;
 312
 313        va_start(list, misc);
 314        for (i = 0; i < data_len; ++i)
 315                scmd->buffer[i] = (u8)va_arg(list, int);
 316        va_end(list);
 317
 318        return smu_queue_cmd(cmd);
 319}
 320EXPORT_SYMBOL(smu_queue_simple);
 321
 322
 323void smu_poll(void)
 324{
 325        u8 gpio;
 326
 327        if (smu == NULL)
 328                return;
 329
 330        gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell);
 331        if ((gpio & 7) == 7)
 332                smu_db_intr(smu->db_irq, smu);
 333}
 334EXPORT_SYMBOL(smu_poll);
 335
 336
 337void smu_done_complete(struct smu_cmd *cmd, void *misc)
 338{
 339        struct completion *comp = misc;
 340
 341        complete(comp);
 342}
 343EXPORT_SYMBOL(smu_done_complete);
 344
 345
 346void smu_spinwait_cmd(struct smu_cmd *cmd)
 347{
 348        while(cmd->status == 1)
 349                smu_poll();
 350}
 351EXPORT_SYMBOL(smu_spinwait_cmd);
 352
 353
 354/* RTC low level commands */
 355static inline int bcd2hex (int n)
 356{
 357        return (((n & 0xf0) >> 4) * 10) + (n & 0xf);
 358}
 359
 360
 361static inline int hex2bcd (int n)
 362{
 363        return ((n / 10) << 4) + (n % 10);
 364}
 365
 366
 367static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf,
 368                                        struct rtc_time *time)
 369{
 370        cmd_buf->cmd = 0x8e;
 371        cmd_buf->length = 8;
 372        cmd_buf->data[0] = 0x80;
 373        cmd_buf->data[1] = hex2bcd(time->tm_sec);
 374        cmd_buf->data[2] = hex2bcd(time->tm_min);
 375        cmd_buf->data[3] = hex2bcd(time->tm_hour);
 376        cmd_buf->data[4] = time->tm_wday;
 377        cmd_buf->data[5] = hex2bcd(time->tm_mday);
 378        cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1;
 379        cmd_buf->data[7] = hex2bcd(time->tm_year - 100);
 380}
 381
 382
 383int smu_get_rtc_time(struct rtc_time *time, int spinwait)
 384{
 385        struct smu_simple_cmd cmd;
 386        int rc;
 387
 388        if (smu == NULL)
 389                return -ENODEV;
 390
 391        memset(time, 0, sizeof(struct rtc_time));
 392        rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL,
 393                              SMU_CMD_RTC_GET_DATETIME);
 394        if (rc)
 395                return rc;
 396        smu_spinwait_simple(&cmd);
 397
 398        time->tm_sec = bcd2hex(cmd.buffer[0]);
 399        time->tm_min = bcd2hex(cmd.buffer[1]);
 400        time->tm_hour = bcd2hex(cmd.buffer[2]);
 401        time->tm_wday = bcd2hex(cmd.buffer[3]);
 402        time->tm_mday = bcd2hex(cmd.buffer[4]);
 403        time->tm_mon = bcd2hex(cmd.buffer[5]) - 1;
 404        time->tm_year = bcd2hex(cmd.buffer[6]) + 100;
 405
 406        return 0;
 407}
 408
 409
 410int smu_set_rtc_time(struct rtc_time *time, int spinwait)
 411{
 412        struct smu_simple_cmd cmd;
 413        int rc;
 414
 415        if (smu == NULL)
 416                return -ENODEV;
 417
 418        rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL,
 419                              SMU_CMD_RTC_SET_DATETIME,
 420                              hex2bcd(time->tm_sec),
 421                              hex2bcd(time->tm_min),
 422                              hex2bcd(time->tm_hour),
 423                              time->tm_wday,
 424                              hex2bcd(time->tm_mday),
 425                              hex2bcd(time->tm_mon) + 1,
 426                              hex2bcd(time->tm_year - 100));
 427        if (rc)
 428                return rc;
 429        smu_spinwait_simple(&cmd);
 430
 431        return 0;
 432}
 433
 434
 435void smu_shutdown(void)
 436{
 437        struct smu_simple_cmd cmd;
 438
 439        if (smu == NULL)
 440                return;
 441
 442        if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL,
 443                             'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0))
 444                return;
 445        smu_spinwait_simple(&cmd);
 446        for (;;)
 447                ;
 448}
 449
 450
 451void smu_restart(void)
 452{
 453        struct smu_simple_cmd cmd;
 454
 455        if (smu == NULL)
 456                return;
 457
 458        if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL,
 459                             'R', 'E', 'S', 'T', 'A', 'R', 'T', 0))
 460                return;
 461        smu_spinwait_simple(&cmd);
 462        for (;;)
 463                ;
 464}
 465
 466
 467int smu_present(void)
 468{
 469        return smu != NULL;
 470}
 471EXPORT_SYMBOL(smu_present);
 472
 473
 474int __init smu_init (void)
 475{
 476        struct device_node *np;
 477        const u32 *data;
 478        int ret = 0;
 479
 480        np = of_find_node_by_type(NULL, "smu");
 481        if (np == NULL)
 482                return -ENODEV;
 483
 484        printk(KERN_INFO "SMU: Driver %s %s\n", VERSION, AUTHOR);
 485
 486        if (smu_cmdbuf_abs == 0) {
 487                printk(KERN_ERR "SMU: Command buffer not allocated !\n");
 488                ret = -EINVAL;
 489                goto fail_np;
 490        }
 491
 492        smu = alloc_bootmem(sizeof(struct smu_device));
 493
 494        spin_lock_init(&smu->lock);
 495        INIT_LIST_HEAD(&smu->cmd_list);
 496        INIT_LIST_HEAD(&smu->cmd_i2c_list);
 497        smu->of_node = np;
 498        smu->db_irq = NO_IRQ;
 499        smu->msg_irq = NO_IRQ;
 500
 501        /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a
 502         * 32 bits value safely
 503         */
 504        smu->cmd_buf_abs = (u32)smu_cmdbuf_abs;
 505        smu->cmd_buf = (struct smu_cmd_buf *)abs_to_virt(smu_cmdbuf_abs);
 506
 507        smu->db_node = of_find_node_by_name(NULL, "smu-doorbell");
 508        if (smu->db_node == NULL) {
 509                printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n");
 510                ret = -ENXIO;
 511                goto fail_bootmem;
 512        }
 513        data = of_get_property(smu->db_node, "reg", NULL);
 514        if (data == NULL) {
 515                printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n");
 516                ret = -ENXIO;
 517                goto fail_db_node;
 518        }
 519
 520        /* Current setup has one doorbell GPIO that does both doorbell
 521         * and ack. GPIOs are at 0x50, best would be to find that out
 522         * in the device-tree though.
 523         */
 524        smu->doorbell = *data;
 525        if (smu->doorbell < 0x50)
 526                smu->doorbell += 0x50;
 527
 528        /* Now look for the smu-interrupt GPIO */
 529        do {
 530                smu->msg_node = of_find_node_by_name(NULL, "smu-interrupt");
 531                if (smu->msg_node == NULL)
 532                        break;
 533                data = of_get_property(smu->msg_node, "reg", NULL);
 534                if (data == NULL) {
 535                        of_node_put(smu->msg_node);
 536                        smu->msg_node = NULL;
 537                        break;
 538                }
 539                smu->msg = *data;
 540                if (smu->msg < 0x50)
 541                        smu->msg += 0x50;
 542        } while(0);
 543
 544        /* Doorbell buffer is currently hard-coded, I didn't find a proper
 545         * device-tree entry giving the address. Best would probably to use
 546         * an offset for K2 base though, but let's do it that way for now.
 547         */
 548        smu->db_buf = ioremap(0x8000860c, 0x1000);
 549        if (smu->db_buf == NULL) {
 550                printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n");
 551                ret = -ENXIO;
 552                goto fail_msg_node;
 553        }
 554
 555        /* U3 has an issue with NAP mode when issuing SMU commands */
 556        smu->broken_nap = pmac_get_uninorth_variant() < 4;
 557        if (smu->broken_nap)
 558                printk(KERN_INFO "SMU: using NAP mode workaround\n");
 559
 560        sys_ctrler = SYS_CTRLER_SMU;
 561        return 0;
 562
 563fail_msg_node:
 564        if (smu->msg_node)
 565                of_node_put(smu->msg_node);
 566fail_db_node:
 567        of_node_put(smu->db_node);
 568fail_bootmem:
 569        free_bootmem((unsigned long)smu, sizeof(struct smu_device));
 570        smu = NULL;
 571fail_np:
 572        of_node_put(np);
 573        return ret;
 574}
 575
 576
 577static int smu_late_init(void)
 578{
 579        if (!smu)
 580                return 0;
 581
 582        init_timer(&smu->i2c_timer);
 583        smu->i2c_timer.function = smu_i2c_retry;
 584        smu->i2c_timer.data = (unsigned long)smu;
 585
 586        if (smu->db_node) {
 587                smu->db_irq = irq_of_parse_and_map(smu->db_node, 0);
 588                if (smu->db_irq == NO_IRQ)
 589                        printk(KERN_ERR "smu: failed to map irq for node %s\n",
 590                               smu->db_node->full_name);
 591        }
 592        if (smu->msg_node) {
 593                smu->msg_irq = irq_of_parse_and_map(smu->msg_node, 0);
 594                if (smu->msg_irq == NO_IRQ)
 595                        printk(KERN_ERR "smu: failed to map irq for node %s\n",
 596                               smu->msg_node->full_name);
 597        }
 598
 599        /*
 600         * Try to request the interrupts
 601         */
 602
 603        if (smu->db_irq != NO_IRQ) {
 604                if (request_irq(smu->db_irq, smu_db_intr,
 605                                IRQF_SHARED, "SMU doorbell", smu) < 0) {
 606                        printk(KERN_WARNING "SMU: can't "
 607                               "request interrupt %d\n",
 608                               smu->db_irq);
 609                        smu->db_irq = NO_IRQ;
 610                }
 611        }
 612
 613        if (smu->msg_irq != NO_IRQ) {
 614                if (request_irq(smu->msg_irq, smu_msg_intr,
 615                                IRQF_SHARED, "SMU message", smu) < 0) {
 616                        printk(KERN_WARNING "SMU: can't "
 617                               "request interrupt %d\n",
 618                               smu->msg_irq);
 619                        smu->msg_irq = NO_IRQ;
 620                }
 621        }
 622
 623        smu_irq_inited = 1;
 624        return 0;
 625}
 626/* This has to be before arch_initcall as the low i2c stuff relies on the
 627 * above having been done before we reach arch_initcalls
 628 */
 629core_initcall(smu_late_init);
 630
 631/*
 632 * sysfs visibility
 633 */
 634
 635static void smu_expose_childs(struct work_struct *unused)
 636{
 637        struct device_node *np;
 638
 639        for (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;)
 640                if (of_device_is_compatible(np, "smu-sensors"))
 641                        of_platform_device_create(np, "smu-sensors",
 642                                                  &smu->of_dev->dev);
 643}
 644
 645static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs);
 646
 647static int smu_platform_probe(struct platform_device* dev)
 648{
 649        if (!smu)
 650                return -ENODEV;
 651        smu->of_dev = dev;
 652
 653        /*
 654         * Ok, we are matched, now expose all i2c busses. We have to defer
 655         * that unfortunately or it would deadlock inside the device model
 656         */
 657        schedule_work(&smu_expose_childs_work);
 658
 659        return 0;
 660}
 661
 662static const struct of_device_id smu_platform_match[] =
 663{
 664        {
 665                .type           = "smu",
 666        },
 667        {},
 668};
 669
 670static struct platform_driver smu_of_platform_driver =
 671{
 672        .driver = {
 673                .name = "smu",
 674                .owner = THIS_MODULE,
 675                .of_match_table = smu_platform_match,
 676        },
 677        .probe          = smu_platform_probe,
 678};
 679
 680static int __init smu_init_sysfs(void)
 681{
 682        /*
 683         * For now, we don't power manage machines with an SMU chip,
 684         * I'm a bit too far from figuring out how that works with those
 685         * new chipsets, but that will come back and bite us
 686         */
 687        platform_driver_register(&smu_of_platform_driver);
 688        return 0;
 689}
 690
 691device_initcall(smu_init_sysfs);
 692
 693struct platform_device *smu_get_ofdev(void)
 694{
 695        if (!smu)
 696                return NULL;
 697        return smu->of_dev;
 698}
 699
 700EXPORT_SYMBOL_GPL(smu_get_ofdev);
 701
 702/*
 703 * i2c interface
 704 */
 705
 706static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail)
 707{
 708        void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done;
 709        void *misc = cmd->misc;
 710        unsigned long flags;
 711
 712        /* Check for read case */
 713        if (!fail && cmd->read) {
 714                if (cmd->pdata[0] < 1)
 715                        fail = 1;
 716                else
 717                        memcpy(cmd->info.data, &cmd->pdata[1],
 718                               cmd->info.datalen);
 719        }
 720
 721        DPRINTK("SMU: completing, success: %d\n", !fail);
 722
 723        /* Update status and mark no pending i2c command with lock
 724         * held so nobody comes in while we dequeue an eventual
 725         * pending next i2c command
 726         */
 727        spin_lock_irqsave(&smu->lock, flags);
 728        smu->cmd_i2c_cur = NULL;
 729        wmb();
 730        cmd->status = fail ? -EIO : 0;
 731
 732        /* Is there another i2c command waiting ? */
 733        if (!list_empty(&smu->cmd_i2c_list)) {
 734                struct smu_i2c_cmd *newcmd;
 735
 736                /* Fetch it, new current, remove from list */
 737                newcmd = list_entry(smu->cmd_i2c_list.next,
 738                                    struct smu_i2c_cmd, link);
 739                smu->cmd_i2c_cur = newcmd;
 740                list_del(&cmd->link);
 741
 742                /* Queue with low level smu */
 743                list_add_tail(&cmd->scmd.link, &smu->cmd_list);
 744                if (smu->cmd_cur == NULL)
 745                        smu_start_cmd();
 746        }
 747        spin_unlock_irqrestore(&smu->lock, flags);
 748
 749        /* Call command completion handler if any */
 750        if (done)
 751                done(cmd, misc);
 752
 753}
 754
 755
 756static void smu_i2c_retry(unsigned long data)
 757{
 758        struct smu_i2c_cmd      *cmd = smu->cmd_i2c_cur;
 759
 760        DPRINTK("SMU: i2c failure, requeuing...\n");
 761
 762        /* requeue command simply by resetting reply_len */
 763        cmd->pdata[0] = 0xff;
 764        cmd->scmd.reply_len = sizeof(cmd->pdata);
 765        smu_queue_cmd(&cmd->scmd);
 766}
 767
 768
 769static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc)
 770{
 771        struct smu_i2c_cmd      *cmd = misc;
 772        int                     fail = 0;
 773
 774        DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n",
 775                cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len);
 776
 777        /* Check for possible status */
 778        if (scmd->status < 0)
 779                fail = 1;
 780        else if (cmd->read) {
 781                if (cmd->stage == 0)
 782                        fail = cmd->pdata[0] != 0;
 783                else
 784                        fail = cmd->pdata[0] >= 0x80;
 785        } else {
 786                fail = cmd->pdata[0] != 0;
 787        }
 788
 789        /* Handle failures by requeuing command, after 5ms interval
 790         */
 791        if (fail && --cmd->retries > 0) {
 792                DPRINTK("SMU: i2c failure, starting timer...\n");
 793                BUG_ON(cmd != smu->cmd_i2c_cur);
 794                if (!smu_irq_inited) {
 795                        mdelay(5);
 796                        smu_i2c_retry(0);
 797                        return;
 798                }
 799                mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5));
 800                return;
 801        }
 802
 803        /* If failure or stage 1, command is complete */
 804        if (fail || cmd->stage != 0) {
 805                smu_i2c_complete_command(cmd, fail);
 806                return;
 807        }
 808
 809        DPRINTK("SMU: going to stage 1\n");
 810
 811        /* Ok, initial command complete, now poll status */
 812        scmd->reply_buf = cmd->pdata;
 813        scmd->reply_len = sizeof(cmd->pdata);
 814        scmd->data_buf = cmd->pdata;
 815        scmd->data_len = 1;
 816        cmd->pdata[0] = 0;
 817        cmd->stage = 1;
 818        cmd->retries = 20;
 819        smu_queue_cmd(scmd);
 820}
 821
 822
 823int smu_queue_i2c(struct smu_i2c_cmd *cmd)
 824{
 825        unsigned long flags;
 826
 827        if (smu == NULL)
 828                return -ENODEV;
 829
 830        /* Fill most fields of scmd */
 831        cmd->scmd.cmd = SMU_CMD_I2C_COMMAND;
 832        cmd->scmd.done = smu_i2c_low_completion;
 833        cmd->scmd.misc = cmd;
 834        cmd->scmd.reply_buf = cmd->pdata;
 835        cmd->scmd.reply_len = sizeof(cmd->pdata);
 836        cmd->scmd.data_buf = (u8 *)(char *)&cmd->info;
 837        cmd->scmd.status = 1;
 838        cmd->stage = 0;
 839        cmd->pdata[0] = 0xff;
 840        cmd->retries = 20;
 841        cmd->status = 1;
 842
 843        /* Check transfer type, sanitize some "info" fields
 844         * based on transfer type and do more checking
 845         */
 846        cmd->info.caddr = cmd->info.devaddr;
 847        cmd->read = cmd->info.devaddr & 0x01;
 848        switch(cmd->info.type) {
 849        case SMU_I2C_TRANSFER_SIMPLE:
 850                memset(&cmd->info.sublen, 0, 4);
 851                break;
 852        case SMU_I2C_TRANSFER_COMBINED:
 853                cmd->info.devaddr &= 0xfe;
 854        case SMU_I2C_TRANSFER_STDSUB:
 855                if (cmd->info.sublen > 3)
 856                        return -EINVAL;
 857                break;
 858        default:
 859                return -EINVAL;
 860        }
 861
 862        /* Finish setting up command based on transfer direction
 863         */
 864        if (cmd->read) {
 865                if (cmd->info.datalen > SMU_I2C_READ_MAX)
 866                        return -EINVAL;
 867                memset(cmd->info.data, 0xff, cmd->info.datalen);
 868                cmd->scmd.data_len = 9;
 869        } else {
 870                if (cmd->info.datalen > SMU_I2C_WRITE_MAX)
 871                        return -EINVAL;
 872                cmd->scmd.data_len = 9 + cmd->info.datalen;
 873        }
 874
 875        DPRINTK("SMU: i2c enqueuing command\n");
 876        DPRINTK("SMU:   %s, len=%d bus=%x addr=%x sub0=%x type=%x\n",
 877                cmd->read ? "read" : "write", cmd->info.datalen,
 878                cmd->info.bus, cmd->info.caddr,
 879                cmd->info.subaddr[0], cmd->info.type);
 880
 881
 882        /* Enqueue command in i2c list, and if empty, enqueue also in
 883         * main command list
 884         */
 885        spin_lock_irqsave(&smu->lock, flags);
 886        if (smu->cmd_i2c_cur == NULL) {
 887                smu->cmd_i2c_cur = cmd;
 888                list_add_tail(&cmd->scmd.link, &smu->cmd_list);
 889                if (smu->cmd_cur == NULL)
 890                        smu_start_cmd();
 891        } else
 892                list_add_tail(&cmd->link, &smu->cmd_i2c_list);
 893        spin_unlock_irqrestore(&smu->lock, flags);
 894
 895        return 0;
 896}
 897
 898/*
 899 * Handling of "partitions"
 900 */
 901
 902static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len)
 903{
 904        DECLARE_COMPLETION_ONSTACK(comp);
 905        unsigned int chunk;
 906        struct smu_cmd cmd;
 907        int rc;
 908        u8 params[8];
 909
 910        /* We currently use a chunk size of 0xe. We could check the
 911         * SMU firmware version and use bigger sizes though
 912         */
 913        chunk = 0xe;
 914
 915        while (len) {
 916                unsigned int clen = min(len, chunk);
 917
 918                cmd.cmd = SMU_CMD_MISC_ee_COMMAND;
 919                cmd.data_len = 7;
 920                cmd.data_buf = params;
 921                cmd.reply_len = chunk;
 922                cmd.reply_buf = dest;
 923                cmd.done = smu_done_complete;
 924                cmd.misc = &comp;
 925                params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC;
 926                params[1] = 0x4;
 927                *((u32 *)&params[2]) = addr;
 928                params[6] = clen;
 929
 930                rc = smu_queue_cmd(&cmd);
 931                if (rc)
 932                        return rc;
 933                wait_for_completion(&comp);
 934                if (cmd.status != 0)
 935                        return rc;
 936                if (cmd.reply_len != clen) {
 937                        printk(KERN_DEBUG "SMU: short read in "
 938                               "smu_read_datablock, got: %d, want: %d\n",
 939                               cmd.reply_len, clen);
 940                        return -EIO;
 941                }
 942                len -= clen;
 943                addr += clen;
 944                dest += clen;
 945        }
 946        return 0;
 947}
 948
 949static struct smu_sdbp_header *smu_create_sdb_partition(int id)
 950{
 951        DECLARE_COMPLETION_ONSTACK(comp);
 952        struct smu_simple_cmd cmd;
 953        unsigned int addr, len, tlen;
 954        struct smu_sdbp_header *hdr;
 955        struct property *prop;
 956
 957        /* First query the partition info */
 958        DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq);
 959        smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2,
 960                         smu_done_complete, &comp,
 961                         SMU_CMD_PARTITION_LATEST, id);
 962        wait_for_completion(&comp);
 963        DPRINTK("SMU: done, status: %d, reply_len: %d\n",
 964                cmd.cmd.status, cmd.cmd.reply_len);
 965
 966        /* Partition doesn't exist (or other error) */
 967        if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6)
 968                return NULL;
 969
 970        /* Fetch address and length from reply */
 971        addr = *((u16 *)cmd.buffer);
 972        len = cmd.buffer[3] << 2;
 973        /* Calucluate total length to allocate, including the 17 bytes
 974         * for "sdb-partition-XX" that we append at the end of the buffer
 975         */
 976        tlen = sizeof(struct property) + len + 18;
 977
 978        prop = kzalloc(tlen, GFP_KERNEL);
 979        if (prop == NULL)
 980                return NULL;
 981        hdr = (struct smu_sdbp_header *)(prop + 1);
 982        prop->name = ((char *)prop) + tlen - 18;
 983        sprintf(prop->name, "sdb-partition-%02x", id);
 984        prop->length = len;
 985        prop->value = hdr;
 986        prop->next = NULL;
 987
 988        /* Read the datablock */
 989        if (smu_read_datablock((u8 *)hdr, addr, len)) {
 990                printk(KERN_DEBUG "SMU: datablock read failed while reading "
 991                       "partition %02x !\n", id);
 992                goto failure;
 993        }
 994
 995        /* Got it, check a few things and create the property */
 996        if (hdr->id != id) {
 997                printk(KERN_DEBUG "SMU: Reading partition %02x and got "
 998                       "%02x !\n", id, hdr->id);
 999                goto failure;
1000        }
1001        if (prom_add_property(smu->of_node, prop)) {
1002                printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x "
1003                       "property !\n", id);
1004                goto failure;
1005        }
1006
1007        return hdr;
1008 failure:
1009        kfree(prop);
1010        return NULL;
1011}
1012
1013/* Note: Only allowed to return error code in pointers (using ERR_PTR)
1014 * when interruptible is 1
1015 */
1016const struct smu_sdbp_header *__smu_get_sdb_partition(int id,
1017                unsigned int *size, int interruptible)
1018{
1019        char pname[32];
1020        const struct smu_sdbp_header *part;
1021
1022        if (!smu)
1023                return NULL;
1024
1025        sprintf(pname, "sdb-partition-%02x", id);
1026
1027        DPRINTK("smu_get_sdb_partition(%02x)\n", id);
1028
1029        if (interruptible) {
1030                int rc;
1031                rc = mutex_lock_interruptible(&smu_part_access);
1032                if (rc)
1033                        return ERR_PTR(rc);
1034        } else
1035                mutex_lock(&smu_part_access);
1036
1037        part = of_get_property(smu->of_node, pname, size);
1038        if (part == NULL) {
1039                DPRINTK("trying to extract from SMU ...\n");
1040                part = smu_create_sdb_partition(id);
1041                if (part != NULL && size)
1042                        *size = part->len << 2;
1043        }
1044        mutex_unlock(&smu_part_access);
1045        return part;
1046}
1047
1048const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size)
1049{
1050        return __smu_get_sdb_partition(id, size, 0);
1051}
1052EXPORT_SYMBOL(smu_get_sdb_partition);
1053
1054
1055/*
1056 * Userland driver interface
1057 */
1058
1059
1060static LIST_HEAD(smu_clist);
1061static DEFINE_SPINLOCK(smu_clist_lock);
1062
1063enum smu_file_mode {
1064        smu_file_commands,
1065        smu_file_events,
1066        smu_file_closing
1067};
1068
1069struct smu_private
1070{
1071        struct list_head        list;
1072        enum smu_file_mode      mode;
1073        int                     busy;
1074        struct smu_cmd          cmd;
1075        spinlock_t              lock;
1076        wait_queue_head_t       wait;
1077        u8                      buffer[SMU_MAX_DATA];
1078};
1079
1080
1081static int smu_open(struct inode *inode, struct file *file)
1082{
1083        struct smu_private *pp;
1084        unsigned long flags;
1085
1086        pp = kzalloc(sizeof(struct smu_private), GFP_KERNEL);
1087        if (pp == 0)
1088                return -ENOMEM;
1089        spin_lock_init(&pp->lock);
1090        pp->mode = smu_file_commands;
1091        init_waitqueue_head(&pp->wait);
1092
1093        mutex_lock(&smu_mutex);
1094        spin_lock_irqsave(&smu_clist_lock, flags);
1095        list_add(&pp->list, &smu_clist);
1096        spin_unlock_irqrestore(&smu_clist_lock, flags);
1097        file->private_data = pp;
1098        mutex_unlock(&smu_mutex);
1099
1100        return 0;
1101}
1102
1103
1104static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc)
1105{
1106        struct smu_private *pp = misc;
1107
1108        wake_up_all(&pp->wait);
1109}
1110
1111
1112static ssize_t smu_write(struct file *file, const char __user *buf,
1113                         size_t count, loff_t *ppos)
1114{
1115        struct smu_private *pp = file->private_data;
1116        unsigned long flags;
1117        struct smu_user_cmd_hdr hdr;
1118        int rc = 0;
1119
1120        if (pp->busy)
1121                return -EBUSY;
1122        else if (copy_from_user(&hdr, buf, sizeof(hdr)))
1123                return -EFAULT;
1124        else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) {
1125                pp->mode = smu_file_events;
1126                return 0;
1127        } else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) {
1128                const struct smu_sdbp_header *part;
1129                part = __smu_get_sdb_partition(hdr.cmd, NULL, 1);
1130                if (part == NULL)
1131                        return -EINVAL;
1132                else if (IS_ERR(part))
1133                        return PTR_ERR(part);
1134                return 0;
1135        } else if (hdr.cmdtype != SMU_CMDTYPE_SMU)
1136                return -EINVAL;
1137        else if (pp->mode != smu_file_commands)
1138                return -EBADFD;
1139        else if (hdr.data_len > SMU_MAX_DATA)
1140                return -EINVAL;
1141
1142        spin_lock_irqsave(&pp->lock, flags);
1143        if (pp->busy) {
1144                spin_unlock_irqrestore(&pp->lock, flags);
1145                return -EBUSY;
1146        }
1147        pp->busy = 1;
1148        pp->cmd.status = 1;
1149        spin_unlock_irqrestore(&pp->lock, flags);
1150
1151        if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) {
1152                pp->busy = 0;
1153                return -EFAULT;
1154        }
1155
1156        pp->cmd.cmd = hdr.cmd;
1157        pp->cmd.data_len = hdr.data_len;
1158        pp->cmd.reply_len = SMU_MAX_DATA;
1159        pp->cmd.data_buf = pp->buffer;
1160        pp->cmd.reply_buf = pp->buffer;
1161        pp->cmd.done = smu_user_cmd_done;
1162        pp->cmd.misc = pp;
1163        rc = smu_queue_cmd(&pp->cmd);
1164        if (rc < 0)
1165                return rc;
1166        return count;
1167}
1168
1169
1170static ssize_t smu_read_command(struct file *file, struct smu_private *pp,
1171                                char __user *buf, size_t count)
1172{
1173        DECLARE_WAITQUEUE(wait, current);
1174        struct smu_user_reply_hdr hdr;
1175        unsigned long flags;
1176        int size, rc = 0;
1177
1178        if (!pp->busy)
1179                return 0;
1180        if (count < sizeof(struct smu_user_reply_hdr))
1181                return -EOVERFLOW;
1182        spin_lock_irqsave(&pp->lock, flags);
1183        if (pp->cmd.status == 1) {
1184                if (file->f_flags & O_NONBLOCK) {
1185                        spin_unlock_irqrestore(&pp->lock, flags);
1186                        return -EAGAIN;
1187                }
1188                add_wait_queue(&pp->wait, &wait);
1189                for (;;) {
1190                        set_current_state(TASK_INTERRUPTIBLE);
1191                        rc = 0;
1192                        if (pp->cmd.status != 1)
1193                                break;
1194                        rc = -ERESTARTSYS;
1195                        if (signal_pending(current))
1196                                break;
1197                        spin_unlock_irqrestore(&pp->lock, flags);
1198                        schedule();
1199                        spin_lock_irqsave(&pp->lock, flags);
1200                }
1201                set_current_state(TASK_RUNNING);
1202                remove_wait_queue(&pp->wait, &wait);
1203        }
1204        spin_unlock_irqrestore(&pp->lock, flags);
1205        if (rc)
1206                return rc;
1207        if (pp->cmd.status != 0)
1208                pp->cmd.reply_len = 0;
1209        size = sizeof(hdr) + pp->cmd.reply_len;
1210        if (count < size)
1211                size = count;
1212        rc = size;
1213        hdr.status = pp->cmd.status;
1214        hdr.reply_len = pp->cmd.reply_len;
1215        if (copy_to_user(buf, &hdr, sizeof(hdr)))
1216                return -EFAULT;
1217        size -= sizeof(hdr);
1218        if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size))
1219                return -EFAULT;
1220        pp->busy = 0;
1221
1222        return rc;
1223}
1224
1225
1226static ssize_t smu_read_events(struct file *file, struct smu_private *pp,
1227                               char __user *buf, size_t count)
1228{
1229        /* Not implemented */
1230        msleep_interruptible(1000);
1231        return 0;
1232}
1233
1234
1235static ssize_t smu_read(struct file *file, char __user *buf,
1236                        size_t count, loff_t *ppos)
1237{
1238        struct smu_private *pp = file->private_data;
1239
1240        if (pp->mode == smu_file_commands)
1241                return smu_read_command(file, pp, buf, count);
1242        if (pp->mode == smu_file_events)
1243                return smu_read_events(file, pp, buf, count);
1244
1245        return -EBADFD;
1246}
1247
1248static unsigned int smu_fpoll(struct file *file, poll_table *wait)
1249{
1250        struct smu_private *pp = file->private_data;
1251        unsigned int mask = 0;
1252        unsigned long flags;
1253
1254        if (pp == 0)
1255                return 0;
1256
1257        if (pp->mode == smu_file_commands) {
1258                poll_wait(file, &pp->wait, wait);
1259
1260                spin_lock_irqsave(&pp->lock, flags);
1261                if (pp->busy && pp->cmd.status != 1)
1262                        mask |= POLLIN;
1263                spin_unlock_irqrestore(&pp->lock, flags);
1264        } if (pp->mode == smu_file_events) {
1265                /* Not yet implemented */
1266        }
1267        return mask;
1268}
1269
1270static int smu_release(struct inode *inode, struct file *file)
1271{
1272        struct smu_private *pp = file->private_data;
1273        unsigned long flags;
1274        unsigned int busy;
1275
1276        if (pp == 0)
1277                return 0;
1278
1279        file->private_data = NULL;
1280
1281        /* Mark file as closing to avoid races with new request */
1282        spin_lock_irqsave(&pp->lock, flags);
1283        pp->mode = smu_file_closing;
1284        busy = pp->busy;
1285
1286        /* Wait for any pending request to complete */
1287        if (busy && pp->cmd.status == 1) {
1288                DECLARE_WAITQUEUE(wait, current);
1289
1290                add_wait_queue(&pp->wait, &wait);
1291                for (;;) {
1292                        set_current_state(TASK_UNINTERRUPTIBLE);
1293                        if (pp->cmd.status != 1)
1294                                break;
1295                        spin_unlock_irqrestore(&pp->lock, flags);
1296                        schedule();
1297                        spin_lock_irqsave(&pp->lock, flags);
1298                }
1299                set_current_state(TASK_RUNNING);
1300                remove_wait_queue(&pp->wait, &wait);
1301        }
1302        spin_unlock_irqrestore(&pp->lock, flags);
1303
1304        spin_lock_irqsave(&smu_clist_lock, flags);
1305        list_del(&pp->list);
1306        spin_unlock_irqrestore(&smu_clist_lock, flags);
1307        kfree(pp);
1308
1309        return 0;
1310}
1311
1312
1313static const struct file_operations smu_device_fops = {
1314        .llseek         = no_llseek,
1315        .read           = smu_read,
1316        .write          = smu_write,
1317        .poll           = smu_fpoll,
1318        .open           = smu_open,
1319        .release        = smu_release,
1320};
1321
1322static struct miscdevice pmu_device = {
1323        MISC_DYNAMIC_MINOR, "smu", &smu_device_fops
1324};
1325
1326static int smu_device_init(void)
1327{
1328        if (!smu)
1329                return -ENODEV;
1330        if (misc_register(&pmu_device) < 0)
1331                printk(KERN_ERR "via-pmu: cannot register misc device.\n");
1332        return 0;
1333}
1334device_initcall(smu_device_init);
1335
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.