1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Compaq iPAQ h3xxx Atmel microcontroller companion support 4 * 5 * This is an Atmel AT90LS8535 with a special flashed-in firmware that 6 * implements the special protocol used by this driver. 7 * 8 * based on previous kernel 2.4 version by Andrew Christian 9 * Author : Alessandro Gardich <gremlin@gremlin.it> 10 * Author : Dmitry Artamonow <mad_soft@inbox.ru> 11 * Author : Linus Walleij <linus.walleij@linaro.org> 12 */ 13 14 #include <linux/module.h> 15 #include <linux/init.h> 16 #include <linux/interrupt.h> 17 #include <linux/pm.h> 18 #include <linux/delay.h> 19 #include <linux/device.h> 20 #include <linux/platform_device.h> 21 #include <linux/io.h> 22 #include <linux/mfd/core.h> 23 #include <linux/mfd/ipaq-micro.h> 24 #include <linux/string.h> 25 #include <linux/random.h> 26 #include <linux/slab.h> 27 #include <linux/list.h> 28 29 #include <mach/hardware.h> 30 31 static void ipaq_micro_trigger_tx(struct ipaq_micro *micro) 32 { 33 struct ipaq_micro_txdev *tx = µ->tx; 34 struct ipaq_micro_msg *msg = micro->msg; 35 int i, bp; 36 u8 checksum; 37 u32 val; 38 39 bp = 0; 40 tx->buf[bp++] = CHAR_SOF; 41 42 checksum = ((msg->id & 0x0f) << 4) | (msg->tx_len & 0x0f); 43 tx->buf[bp++] = checksum; 44 45 for (i = 0; i < msg->tx_len; i++) { 46 tx->buf[bp++] = msg->tx_data[i]; 47 checksum += msg->tx_data[i]; 48 } 49 50 tx->buf[bp++] = checksum; 51 tx->len = bp; 52 tx->index = 0; 53 54 /* Enable interrupt */ 55 val = readl(micro->base + UTCR3); 56 val |= UTCR3_TIE; 57 writel(val, micro->base + UTCR3); 58 } 59 60 int ipaq_micro_tx_msg(struct ipaq_micro *micro, struct ipaq_micro_msg *msg) 61 { 62 unsigned long flags; 63 64 dev_dbg(micro->dev, "TX msg: %02x, %d bytes\n", msg->id, msg->tx_len); 65 66 spin_lock_irqsave(µ->lock, flags); 67 if (micro->msg) { 68 list_add_tail(&msg->node, µ->queue); 69 spin_unlock_irqrestore(µ->lock, flags); 70 return 0; 71 } 72 micro->msg = msg; 73 ipaq_micro_trigger_tx(micro); 74 spin_unlock_irqrestore(µ->lock, flags); 75 return 0; 76 } 77 EXPORT_SYMBOL(ipaq_micro_tx_msg); 78 79 static void micro_rx_msg(struct ipaq_micro *micro, u8 id, int len, u8 *data) 80 { 81 int i; 82 83 dev_dbg(micro->dev, "RX msg: %02x, %d bytes\n", id, len); 84 85 spin_lock(µ->lock); 86 switch (id) { 87 case MSG_VERSION: 88 case MSG_EEPROM_READ: 89 case MSG_EEPROM_WRITE: 90 case MSG_BACKLIGHT: 91 case MSG_NOTIFY_LED: 92 case MSG_THERMAL_SENSOR: 93 case MSG_BATTERY: 94 /* Handle synchronous messages */ 95 if (micro->msg && micro->msg->id == id) { 96 struct ipaq_micro_msg *msg = micro->msg; 97 98 memcpy(msg->rx_data, data, len); 99 msg->rx_len = len; 100 complete(µ->msg->ack); 101 if (!list_empty(µ->queue)) { 102 micro->msg = list_entry(micro->queue.next, 103 struct ipaq_micro_msg, 104 node); 105 list_del_init(µ->msg->node); 106 ipaq_micro_trigger_tx(micro); 107 } else 108 micro->msg = NULL; 109 dev_dbg(micro->dev, "OK RX message 0x%02x\n", id); 110 } else { 111 dev_err(micro->dev, 112 "out of band RX message 0x%02x\n", id); 113 if (!micro->msg) 114 dev_info(micro->dev, "no message queued\n"); 115 else 116 dev_info(micro->dev, "expected message %02x\n", 117 micro->msg->id); 118 } 119 break; 120 case MSG_KEYBOARD: 121 if (micro->key) 122 micro->key(micro->key_data, len, data); 123 else 124 dev_dbg(micro->dev, "key message ignored, no handle\n"); 125 break; 126 case MSG_TOUCHSCREEN: 127 if (micro->ts) 128 micro->ts(micro->ts_data, len, data); 129 else 130 dev_dbg(micro->dev, "touchscreen message ignored, no handle\n"); 131 break; 132 default: 133 dev_err(micro->dev, 134 "unknown msg %d [%d] ", id, len); 135 for (i = 0; i < len; ++i) 136 pr_cont("0x%02x ", data[i]); 137 pr_cont("\n"); 138 } 139 spin_unlock(µ->lock); 140 } 141 142 static void micro_process_char(struct ipaq_micro *micro, u8 ch) 143 { 144 struct ipaq_micro_rxdev *rx = µ->rx; 145 146 switch (rx->state) { 147 case STATE_SOF: /* Looking for SOF */ 148 if (ch == CHAR_SOF) 149 rx->state = STATE_ID; /* Next byte is the id and len */ 150 break; 151 case STATE_ID: /* Looking for id and len byte */ 152 rx->id = (ch & 0xf0) >> 4; 153 rx->len = (ch & 0x0f); 154 rx->index = 0; 155 rx->chksum = ch; 156 rx->state = (rx->len > 0) ? STATE_DATA : STATE_CHKSUM; 157 break; 158 case STATE_DATA: /* Looking for 'len' data bytes */ 159 rx->chksum += ch; 160 rx->buf[rx->index] = ch; 161 if (++rx->index == rx->len) 162 rx->state = STATE_CHKSUM; 163 break; 164 case STATE_CHKSUM: /* Looking for the checksum */ 165 if (ch == rx->chksum) 166 micro_rx_msg(micro, rx->id, rx->len, rx->buf); 167 rx->state = STATE_SOF; 168 break; 169 } 170 } 171 172 static void micro_rx_chars(struct ipaq_micro *micro) 173 { 174 u32 status, ch; 175 176 while ((status = readl(micro->base + UTSR1)) & UTSR1_RNE) { 177 ch = readl(micro->base + UTDR); 178 if (status & UTSR1_PRE) 179 dev_err(micro->dev, "rx: parity error\n"); 180 else if (status & UTSR1_FRE) 181 dev_err(micro->dev, "rx: framing error\n"); 182 else if (status & UTSR1_ROR) 183 dev_err(micro->dev, "rx: overrun error\n"); 184 micro_process_char(micro, ch); 185 } 186 } 187 188 static void ipaq_micro_get_version(struct ipaq_micro *micro) 189 { 190 struct ipaq_micro_msg msg = { 191 .id = MSG_VERSION, 192 }; 193 194 ipaq_micro_tx_msg_sync(micro, &msg); 195 if (msg.rx_len == 4) { 196 memcpy(micro->version, msg.rx_data, 4); 197 micro->version[4] = '\0'; 198 } else if (msg.rx_len == 9) { 199 memcpy(micro->version, msg.rx_data, 4); 200 micro->version[4] = '\0'; 201 /* Bytes 4-7 are "pack", byte 8 is "boot type" */ 202 } else { 203 dev_err(micro->dev, 204 "illegal version message %d bytes\n", msg.rx_len); 205 } 206 } 207 208 static void ipaq_micro_eeprom_read(struct ipaq_micro *micro, 209 u8 address, u8 len, u8 *data) 210 { 211 struct ipaq_micro_msg msg = { 212 .id = MSG_EEPROM_READ, 213 }; 214 u8 i; 215 216 for (i = 0; i < len; i++) { 217 msg.tx_data[0] = address + i; 218 msg.tx_data[1] = 1; 219 msg.tx_len = 2; 220 ipaq_micro_tx_msg_sync(micro, &msg); 221 memcpy(data + (i * 2), msg.rx_data, 2); 222 } 223 } 224 225 static char *ipaq_micro_str(u8 *wchar, u8 len) 226 { 227 char retstr[256]; 228 u8 i; 229 230 for (i = 0; i < len / 2; i++) 231 retstr[i] = wchar[i * 2]; 232 return kstrdup(retstr, GFP_KERNEL); 233 } 234 235 static u16 ipaq_micro_to_u16(u8 *data) 236 { 237 return data[1] << 8 | data[0]; 238 } 239 240 static void __init ipaq_micro_eeprom_dump(struct ipaq_micro *micro) 241 { 242 u8 dump[256]; 243 char *str; 244 245 ipaq_micro_eeprom_read(micro, 0, 128, dump); 246 str = ipaq_micro_str(dump, 10); 247 if (str) { 248 dev_info(micro->dev, "HW version %s\n", str); 249 kfree(str); 250 } 251 str = ipaq_micro_str(dump+10, 40); 252 if (str) { 253 dev_info(micro->dev, "serial number: %s\n", str); 254 /* Feed the random pool with this */ 255 add_device_randomness(str, strlen(str)); 256 kfree(str); 257 } 258 str = ipaq_micro_str(dump+50, 20); 259 if (str) { 260 dev_info(micro->dev, "module ID: %s\n", str); 261 kfree(str); 262 } 263 str = ipaq_micro_str(dump+70, 10); 264 if (str) { 265 dev_info(micro->dev, "product revision: %s\n", str); 266 kfree(str); 267 } 268 dev_info(micro->dev, "product ID: %u\n", ipaq_micro_to_u16(dump+80)); 269 dev_info(micro->dev, "frame rate: %u fps\n", 270 ipaq_micro_to_u16(dump+82)); 271 dev_info(micro->dev, "page mode: %u\n", ipaq_micro_to_u16(dump+84)); 272 dev_info(micro->dev, "country ID: %u\n", ipaq_micro_to_u16(dump+86)); 273 dev_info(micro->dev, "color display: %s\n", 274 ipaq_micro_to_u16(dump+88) ? "yes" : "no"); 275 dev_info(micro->dev, "ROM size: %u MiB\n", ipaq_micro_to_u16(dump+90)); 276 dev_info(micro->dev, "RAM size: %u KiB\n", ipaq_micro_to_u16(dump+92)); 277 dev_info(micro->dev, "screen: %u x %u\n", 278 ipaq_micro_to_u16(dump+94), ipaq_micro_to_u16(dump+96)); 279 } 280 281 static void micro_tx_chars(struct ipaq_micro *micro) 282 { 283 struct ipaq_micro_txdev *tx = µ->tx; 284 u32 val; 285 286 while ((tx->index < tx->len) && 287 (readl(micro->base + UTSR1) & UTSR1_TNF)) { 288 writel(tx->buf[tx->index], micro->base + UTDR); 289 tx->index++; 290 } 291 292 /* Stop interrupts */ 293 val = readl(micro->base + UTCR3); 294 val &= ~UTCR3_TIE; 295 writel(val, micro->base + UTCR3); 296 } 297 298 static void micro_reset_comm(struct ipaq_micro *micro) 299 { 300 struct ipaq_micro_rxdev *rx = µ->rx; 301 u32 val; 302 303 if (micro->msg) 304 complete(µ->msg->ack); 305 306 /* Initialize Serial channel protocol frame */ 307 rx->state = STATE_SOF; /* Reset the state machine */ 308 309 /* Set up interrupts */ 310 writel(0x01, micro->sdlc + 0x0); /* Select UART mode */ 311 312 /* Clean up CR3 */ 313 writel(0x0, micro->base + UTCR3); 314 315 /* Format: 8N1 */ 316 writel(UTCR0_8BitData | UTCR0_1StpBit, micro->base + UTCR0); 317 318 /* Baud rate: 115200 */ 319 writel(0x0, micro->base + UTCR1); 320 writel(0x1, micro->base + UTCR2); 321 322 /* Clear SR0 */ 323 writel(0xff, micro->base + UTSR0); 324 325 /* Enable RX int, disable TX int */ 326 writel(UTCR3_TXE | UTCR3_RXE | UTCR3_RIE, micro->base + UTCR3); 327 val = readl(micro->base + UTCR3); 328 val &= ~UTCR3_TIE; 329 writel(val, micro->base + UTCR3); 330 } 331 332 static irqreturn_t micro_serial_isr(int irq, void *dev_id) 333 { 334 struct ipaq_micro *micro = dev_id; 335 struct ipaq_micro_txdev *tx = µ->tx; 336 u32 status; 337 338 status = readl(micro->base + UTSR0); 339 do { 340 if (status & (UTSR0_RID | UTSR0_RFS)) { 341 if (status & UTSR0_RID) 342 /* Clear the Receiver IDLE bit */ 343 writel(UTSR0_RID, micro->base + UTSR0); 344 micro_rx_chars(micro); 345 } 346 347 /* Clear break bits */ 348 if (status & (UTSR0_RBB | UTSR0_REB)) 349 writel(status & (UTSR0_RBB | UTSR0_REB), 350 micro->base + UTSR0); 351 352 if (status & UTSR0_TFS) 353 micro_tx_chars(micro); 354 355 status = readl(micro->base + UTSR0); 356 357 } while (((tx->index < tx->len) && (status & UTSR0_TFS)) || 358 (status & (UTSR0_RFS | UTSR0_RID))); 359 360 return IRQ_HANDLED; 361 } 362 363 static const struct mfd_cell micro_cells[] = { 364 { .name = "ipaq-micro-backlight", }, 365 { .name = "ipaq-micro-battery", }, 366 { .name = "ipaq-micro-keys", }, 367 { .name = "ipaq-micro-ts", }, 368 { .name = "ipaq-micro-leds", }, 369 }; 370 371 static int __maybe_unused micro_resume(struct device *dev) 372 { 373 struct ipaq_micro *micro = dev_get_drvdata(dev); 374 375 micro_reset_comm(micro); 376 mdelay(10); 377 378 return 0; 379 } 380 381 static int __init micro_probe(struct platform_device *pdev) 382 { 383 struct ipaq_micro *micro; 384 struct resource *res; 385 int ret; 386 int irq; 387 388 micro = devm_kzalloc(&pdev->dev, sizeof(*micro), GFP_KERNEL); 389 if (!micro) 390 return -ENOMEM; 391 392 micro->dev = &pdev->dev; 393 394 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 395 micro->base = devm_ioremap_resource(&pdev->dev, res); 396 if (IS_ERR(micro->base)) 397 return PTR_ERR(micro->base); 398 399 micro->sdlc = devm_platform_ioremap_resource(pdev, 1); 400 if (IS_ERR(micro->sdlc)) 401 return PTR_ERR(micro->sdlc); 402 403 micro_reset_comm(micro); 404 405 irq = platform_get_irq(pdev, 0); 406 if (irq < 0) 407 return -EINVAL; 408 ret = devm_request_irq(&pdev->dev, irq, micro_serial_isr, 409 IRQF_SHARED, "ipaq-micro", 410 micro); 411 if (ret) { 412 dev_err(&pdev->dev, "unable to grab serial port IRQ\n"); 413 return ret; 414 } else 415 dev_info(&pdev->dev, "grabbed serial port IRQ\n"); 416 417 spin_lock_init(µ->lock); 418 INIT_LIST_HEAD(µ->queue); 419 platform_set_drvdata(pdev, micro); 420 421 ret = mfd_add_devices(&pdev->dev, pdev->id, micro_cells, 422 ARRAY_SIZE(micro_cells), NULL, 0, NULL); 423 if (ret) { 424 dev_err(&pdev->dev, "error adding MFD cells"); 425 return ret; 426 } 427 428 /* Check version */ 429 ipaq_micro_get_version(micro); 430 dev_info(&pdev->dev, "Atmel micro ASIC version %s\n", micro->version); 431 ipaq_micro_eeprom_dump(micro); 432 433 return 0; 434 } 435 436 static const struct dev_pm_ops micro_dev_pm_ops = { 437 SET_SYSTEM_SLEEP_PM_OPS(NULL, micro_resume) 438 }; 439 440 static struct platform_driver micro_device_driver = { 441 .driver = { 442 .name = "ipaq-h3xxx-micro", 443 .pm = µ_dev_pm_ops, 444 .suppress_bind_attrs = true, 445 }, 446 }; 447 builtin_platform_driver_probe(micro_device_driver, micro_probe); 448