drivers/mfd/ipaq-micro.c

   1 /*
   2  * Compaq iPAQ h3xxx Atmel microcontroller companion support
   3  *
   4  * This is an Atmel AT90LS8535 with a special flashed-in firmware that
   5  * implements the special protocol used by this driver.
   6  *
   7  * based on previous kernel 2.4 version by Andrew Christian
   8  * Author : Alessandro Gardich <gremlin@gremlin.it>
   9  * Author : Dmitry Artamonow <mad_soft@inbox.ru>
  10  * Author : Linus Walleij <linus.walleij@linaro.org>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License version 2 as
  14  * published by the Free Software Foundation.
  15  */
  16
  17 #include <linux/module.h>
  18 #include <linux/init.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/pm.h>
  21 #include <linux/delay.h>
  22 #include <linux/device.h>
  23 #include <linux/platform_device.h>
  24 #include <linux/io.h>
  25 #include <linux/mfd/core.h>
  26 #include <linux/mfd/ipaq-micro.h>
  27 #include <linux/string.h>
  28 #include <linux/random.h>
  29 #include <linux/slab.h>
  30 #include <linux/list.h>
  31
  32 #include <mach/hardware.h>
  33
  34 static void ipaq_micro_trigger_tx(struct ipaq_micro *micro)
  35 {
  36         struct ipaq_micro_txdev *tx = &micro->tx;
  37         struct ipaq_micro_msg *msg = micro->msg;
  38         int i, bp;
  39         u8 checksum;
  40         u32 val;
  41
  42         bp = 0;
  43         tx->buf[bp++] = CHAR_SOF;
  44
  45         checksum = ((msg->id & 0x0f) << 4) | (msg->tx_len & 0x0f);
  46         tx->buf[bp++] = checksum;
  47
  48         for (i = 0; i < msg->tx_len; i++) {
  49                 tx->buf[bp++] = msg->tx_data[i];
  50                 checksum += msg->tx_data[i];
  51         }
  52
  53         tx->buf[bp++] = checksum;
  54         tx->len = bp;
  55         tx->index = 0;
  56         print_hex_dump(KERN_DEBUG, "data: ", DUMP_PREFIX_OFFSET, 16, 1,
  57                        tx->buf, tx->len, true);
  58
  59         /* Enable interrupt */
  60         val = readl(micro->base + UTCR3);
  61         val |= UTCR3_TIE;
  62         writel(val, micro->base + UTCR3);
  63 }
  64
  65 int ipaq_micro_tx_msg(struct ipaq_micro *micro, struct ipaq_micro_msg *msg)
  66 {
  67         unsigned long flags;
  68
  69         dev_dbg(micro->dev, "TX msg: %02x, %d bytes\n", msg->id, msg->tx_len);
  70
  71         spin_lock_irqsave(&micro->lock, flags);
  72         if (micro->msg) {
  73                 list_add_tail(&msg->node, &micro->queue);
  74                 spin_unlock_irqrestore(&micro->lock, flags);
  75                 return 0;
  76         }
  77         micro->msg = msg;
  78         ipaq_micro_trigger_tx(micro);
  79         spin_unlock_irqrestore(&micro->lock, flags);
  80         return 0;
  81 }
  82 EXPORT_SYMBOL(ipaq_micro_tx_msg);
  83
  84 static void micro_rx_msg(struct ipaq_micro *micro, u8 id, int len, u8 *data)
  85 {
  86         int i;
  87
  88         dev_dbg(micro->dev, "RX msg: %02x, %d bytes\n", id, len);
  89
  90         spin_lock(&micro->lock);
  91         switch (id) {
  92         case MSG_VERSION:
  93         case MSG_EEPROM_READ:
  94         case MSG_EEPROM_WRITE:
  95         case MSG_BACKLIGHT:
  96         case MSG_NOTIFY_LED:
  97         case MSG_THERMAL_SENSOR:
  98         case MSG_BATTERY:
  99                 /* Handle synchronous messages */
 100                 if (micro->msg && micro->msg->id == id) {
 101                         struct ipaq_micro_msg *msg = micro->msg;
 102
 103                         memcpy(msg->rx_data, data, len);
 104                         msg->rx_len = len;
 105                         complete(&micro->msg->ack);
 106                         if (!list_empty(&micro->queue)) {
 107                                 micro->msg = list_entry(micro->queue.next,
 108                                                         struct ipaq_micro_msg,
 109                                                         node);
 110                                 list_del_init(&micro->msg->node);
 111                                 ipaq_micro_trigger_tx(micro);
 112                         } else
 113                                 micro->msg = NULL;
 114                         dev_dbg(micro->dev, "OK RX message 0x%02x\n", id);
 115                 } else {
 116                         dev_err(micro->dev,
 117                                 "out of band RX message 0x%02x\n", id);
 118                         if (!micro->msg)
 119                                 dev_info(micro->dev, "no message queued\n");
 120                         else
 121                                 dev_info(micro->dev, "expected message %02x\n",
 122                                          micro->msg->id);
 123                 }
 124                 break;
 125         case MSG_KEYBOARD:
 126                 if (micro->key)
 127                         micro->key(micro->key_data, len, data);
 128                 else
 129                         dev_dbg(micro->dev, "key message ignored, no handle\n");
 130                 break;
 131         case MSG_TOUCHSCREEN:
 132                 if (micro->ts)
 133                         micro->ts(micro->ts_data, len, data);
 134                 else
 135                         dev_dbg(micro->dev, "touchscreen message ignored, no handle\n");
 136                 break;
 137         default:
 138                 dev_err(micro->dev,
 139                         "unknown msg %d [%d] ", id, len);
 140                 for (i = 0; i < len; ++i)
 141                         pr_cont("0x%02x ", data[i]);
 142                 pr_cont("\n");
 143         }
 144         spin_unlock(&micro->lock);
 145 }
 146
 147 static void micro_process_char(struct ipaq_micro *micro, u8 ch)
 148 {
 149         struct ipaq_micro_rxdev *rx = &micro->rx;
 150
 151         switch (rx->state) {
 152         case STATE_SOF: /* Looking for SOF */
 153                 if (ch == CHAR_SOF)
 154                         rx->state = STATE_ID; /* Next byte is the id and len */
 155                 break;
 156         case STATE_ID: /* Looking for id and len byte */
 157                 rx->id = (ch & 0xf0) >> 4;
 158                 rx->len = (ch & 0x0f);
 159                 rx->index = 0;
 160                 rx->chksum = ch;
 161                 rx->state = (rx->len > 0) ? STATE_DATA : STATE_CHKSUM;
 162                 break;
 163         case STATE_DATA: /* Looking for 'len' data bytes */
 164                 rx->chksum += ch;
 165                 rx->buf[rx->index] = ch;
 166                 if (++rx->index == rx->len)
 167                         rx->state = STATE_CHKSUM;
 168                 break;
 169         case STATE_CHKSUM: /* Looking for the checksum */
 170                 if (ch == rx->chksum)
 171                         micro_rx_msg(micro, rx->id, rx->len, rx->buf);
 172                 rx->state = STATE_SOF;
 173                 break;
 174         }
 175 }
 176
 177 static void micro_rx_chars(struct ipaq_micro *micro)
 178 {
 179         u32 status, ch;
 180
 181         while ((status = readl(micro->base + UTSR1)) & UTSR1_RNE) {
 182                 ch = readl(micro->base + UTDR);
 183                 if (status & UTSR1_PRE)
 184                         dev_err(micro->dev, "rx: parity error\n");
 185                 else if (status & UTSR1_FRE)
 186                         dev_err(micro->dev, "rx: framing error\n");
 187                 else if (status & UTSR1_ROR)
 188                         dev_err(micro->dev, "rx: overrun error\n");
 189                 micro_process_char(micro, ch);
 190         }
 191 }
 192
 193 static void ipaq_micro_get_version(struct ipaq_micro *micro)
 194 {
 195         struct ipaq_micro_msg msg = {
 196                 .id = MSG_VERSION,
 197         };
 198
 199         ipaq_micro_tx_msg_sync(micro, &msg);
 200         if (msg.rx_len == 4) {
 201                 memcpy(micro->version, msg.rx_data, 4);
 202                 micro->version[4] = '\0';
 203         } else if (msg.rx_len == 9) {
 204                 memcpy(micro->version, msg.rx_data, 4);
 205                 micro->version[4] = '\0';
 206                 /* Bytes 4-7 are "pack", byte 8 is "boot type" */
 207         } else {
 208                 dev_err(micro->dev,
 209                         "illegal version message %d bytes\n", msg.rx_len);
 210         }
 211 }
 212
 213 static void ipaq_micro_eeprom_read(struct ipaq_micro *micro,
 214                                    u8 address, u8 len, u8 *data)
 215 {
 216         struct ipaq_micro_msg msg = {
 217                 .id = MSG_EEPROM_READ,
 218         };
 219         u8 i;
 220
 221         for (i = 0; i < len; i++) {
 222                 msg.tx_data[0] = address + i;
 223                 msg.tx_data[1] = 1;
 224                 msg.tx_len = 2;
 225                 ipaq_micro_tx_msg_sync(micro, &msg);
 226                 memcpy(data + (i * 2), msg.rx_data, 2);
 227         }
 228 }
 229
 230 static char *ipaq_micro_str(u8 *wchar, u8 len)
 231 {
 232         char retstr[256];
 233         u8 i;
 234
 235         for (i = 0; i < len / 2; i++)
 236                 retstr[i] = wchar[i * 2];
 237         return kstrdup(retstr, GFP_KERNEL);
 238 }
 239
 240 static u16 ipaq_micro_to_u16(u8 *data)
 241 {
 242         return data[1] << 8 | data[0];
 243 }
 244
 245 static void ipaq_micro_eeprom_dump(struct ipaq_micro *micro)
 246 {
 247         u8 dump[256];
 248         char *str;
 249
 250         ipaq_micro_eeprom_read(micro, 0, 128, dump);
 251         str = ipaq_micro_str(dump, 10);
 252         if (str) {
 253                 dev_info(micro->dev, "HM version %s\n", str);
 254                 kfree(str);
 255         }
 256         str = ipaq_micro_str(dump+10, 40);
 257         if (str) {
 258                 dev_info(micro->dev, "serial number: %s\n", str);
 259                 /* Feed the random pool with this */
 260                 add_device_randomness(str, strlen(str));
 261                 kfree(str);
 262         }
 263         str = ipaq_micro_str(dump+50, 20);
 264         if (str) {
 265                 dev_info(micro->dev, "module ID: %s\n", str);
 266                 kfree(str);
 267         }
 268         str = ipaq_micro_str(dump+70, 10);
 269         if (str) {
 270                 dev_info(micro->dev, "product revision: %s\n", str);
 271                 kfree(str);
 272         }
 273         dev_info(micro->dev, "product ID: %u\n", ipaq_micro_to_u16(dump+80));
 274         dev_info(micro->dev, "frame rate: %u fps\n",
 275                  ipaq_micro_to_u16(dump+82));
 276         dev_info(micro->dev, "page mode: %u\n", ipaq_micro_to_u16(dump+84));
 277         dev_info(micro->dev, "country ID: %u\n", ipaq_micro_to_u16(dump+86));
 278         dev_info(micro->dev, "color display: %s\n",
 279                  ipaq_micro_to_u16(dump+88) ? "yes" : "no");
 280         dev_info(micro->dev, "ROM size: %u MiB\n", ipaq_micro_to_u16(dump+90));
 281         dev_info(micro->dev, "RAM size: %u KiB\n", ipaq_micro_to_u16(dump+92));
 282         dev_info(micro->dev, "screen: %u x %u\n",
 283                  ipaq_micro_to_u16(dump+94), ipaq_micro_to_u16(dump+96));
 284         print_hex_dump(KERN_DEBUG, "eeprom: ", DUMP_PREFIX_OFFSET, 16, 1,
 285                        dump, 256, true);
 286
 287 }
 288
 289 static void micro_tx_chars(struct ipaq_micro *micro)
 290 {
 291         struct ipaq_micro_txdev *tx = &micro->tx;
 292         u32 val;
 293
 294         while ((tx->index < tx->len) &&
 295                (readl(micro->base + UTSR1) & UTSR1_TNF)) {
 296                 writel(tx->buf[tx->index], micro->base + UTDR);
 297                 tx->index++;
 298         }
 299
 300         /* Stop interrupts */
 301         val = readl(micro->base + UTCR3);
 302         val &= ~UTCR3_TIE;
 303         writel(val, micro->base + UTCR3);
 304 }
 305
 306 static void micro_reset_comm(struct ipaq_micro *micro)
 307 {
 308         struct ipaq_micro_rxdev *rx = &micro->rx;
 309         u32 val;
 310
 311         if (micro->msg)
 312                 complete(&micro->msg->ack);
 313
 314         /* Initialize Serial channel protocol frame */
 315         rx->state = STATE_SOF;  /* Reset the state machine */
 316
 317         /* Set up interrupts */
 318         writel(0x01, micro->sdlc + 0x0); /* Select UART mode */
 319
 320         /* Clean up CR3 */
 321         writel(0x0, micro->base + UTCR3);
 322
 323         /* Format: 8N1 */
 324         writel(UTCR0_8BitData | UTCR0_1StpBit, micro->base + UTCR0);
 325
 326         /* Baud rate: 115200 */
 327         writel(0x0, micro->base + UTCR1);
 328         writel(0x1, micro->base + UTCR2);
 329
 330         /* Clear SR0 */
 331         writel(0xff, micro->base + UTSR0);
 332
 333         /* Enable RX int, disable TX int */
 334         writel(UTCR3_TXE | UTCR3_RXE | UTCR3_RIE, micro->base + UTCR3);
 335         val = readl(micro->base + UTCR3);
 336         val &= ~UTCR3_TIE;
 337         writel(val, micro->base + UTCR3);
 338 }
 339
 340 static irqreturn_t micro_serial_isr(int irq, void *dev_id)
 341 {
 342         struct ipaq_micro *micro = dev_id;
 343         struct ipaq_micro_txdev *tx = &micro->tx;
 344         u32 status;
 345
 346         status = readl(micro->base + UTSR0);
 347         do {
 348                 if (status & (UTSR0_RID | UTSR0_RFS)) {
 349                         if (status & UTSR0_RID)
 350                                 /* Clear the Receiver IDLE bit */
 351                                 writel(UTSR0_RID, micro->base + UTSR0);
 352                         micro_rx_chars(micro);
 353                 }
 354
 355                 /* Clear break bits */
 356                 if (status & (UTSR0_RBB | UTSR0_REB))
 357                         writel(status & (UTSR0_RBB | UTSR0_REB),
 358                                micro->base + UTSR0);
 359
 360                 if (status & UTSR0_TFS)
 361                         micro_tx_chars(micro);
 362
 363                 status = readl(micro->base + UTSR0);
 364
 365         } while (((tx->index < tx->len) && (status & UTSR0_TFS)) ||
 366                  (status & (UTSR0_RFS | UTSR0_RID)));
 367
 368         return IRQ_HANDLED;
 369 }
 370
 371 static const struct mfd_cell micro_cells[] = {
 372         { .name = "ipaq-micro-backlight", },
 373         { .name = "ipaq-micro-battery", },
 374         { .name = "ipaq-micro-keys", },
 375         { .name = "ipaq-micro-ts", },
 376         { .name = "ipaq-micro-leds", },
 377 };
 378
 379 static int micro_resume(struct device *dev)
 380 {
 381         struct ipaq_micro *micro = dev_get_drvdata(dev);
 382
 383         micro_reset_comm(micro);
 384         mdelay(10);
 385
 386         return 0;
 387 }
 388
 389 static int micro_probe(struct platform_device *pdev)
 390 {
 391         struct ipaq_micro *micro;
 392         struct resource *res;
 393         int ret;
 394         int irq;
 395
 396         micro = devm_kzalloc(&pdev->dev, sizeof(*micro), GFP_KERNEL);
 397         if (!micro)
 398                 return -ENOMEM;
 399
 400         micro->dev = &pdev->dev;
 401
 402         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 403         if (!res)
 404                 return -EINVAL;
 405
 406         micro->base = devm_ioremap_resource(&pdev->dev, res);
 407         if (IS_ERR(micro->base))
 408                 return PTR_ERR(micro->base);
 409
 410         res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 411         if (!res)
 412                 return -EINVAL;
 413
 414         micro->sdlc = devm_ioremap_resource(&pdev->dev, res);
 415         if (IS_ERR(micro->sdlc))
 416                 return PTR_ERR(micro->sdlc);
 417
 418         micro_reset_comm(micro);
 419
 420         irq = platform_get_irq(pdev, 0);
 421         if (!irq)
 422                 return -EINVAL;
 423         ret = devm_request_irq(&pdev->dev, irq, micro_serial_isr,
 424                                IRQF_SHARED, "ipaq-micro",
 425                                micro);
 426         if (ret) {
 427                 dev_err(&pdev->dev, "unable to grab serial port IRQ\n");
 428                 return ret;
 429         } else
 430                 dev_info(&pdev->dev, "grabbed serial port IRQ\n");
 431
 432         spin_lock_init(&micro->lock);
 433         INIT_LIST_HEAD(&micro->queue);
 434         platform_set_drvdata(pdev, micro);
 435
 436         ret = mfd_add_devices(&pdev->dev, pdev->id, micro_cells,
 437                               ARRAY_SIZE(micro_cells), NULL, 0, NULL);
 438         if (ret) {
 439                 dev_err(&pdev->dev, "error adding MFD cells");
 440                 return ret;
 441         }
 442
 443         /* Check version */
 444         ipaq_micro_get_version(micro);
 445         dev_info(&pdev->dev, "Atmel micro ASIC version %s\n", micro->version);
 446         ipaq_micro_eeprom_dump(micro);
 447
 448         return 0;
 449 }
 450
 451 static int micro_remove(struct platform_device *pdev)
 452 {
 453         struct ipaq_micro *micro = platform_get_drvdata(pdev);
 454         u32 val;
 455
 456         mfd_remove_devices(&pdev->dev);
 457
 458         val = readl(micro->base + UTCR3);
 459         val &= ~(UTCR3_RXE | UTCR3_RIE); /* disable receive interrupt */
 460         val &= ~(UTCR3_TXE | UTCR3_TIE); /* disable transmit interrupt */
 461         writel(val, micro->base + UTCR3);
 462
 463         return 0;
 464 }
 465
 466 static const struct dev_pm_ops micro_dev_pm_ops = {
 467         SET_SYSTEM_SLEEP_PM_OPS(NULL, micro_resume)
 468 };
 469
 470 static struct platform_driver micro_device_driver = {
 471         .driver   = {
 472                 .name   = "ipaq-h3xxx-micro",
 473                 .pm     = &micro_dev_pm_ops,
 474         },
 475         .probe    = micro_probe,
 476         .remove   = micro_remove,
 477         /* .shutdown = micro_suspend, // FIXME */
 478 };
 479 module_platform_driver(micro_device_driver);
 480
 481 MODULE_LICENSE("GPL");
 482 MODULE_DESCRIPTION("driver for iPAQ Atmel micro core and backlight");