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