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
ipaq_micro_trigger_tx(struct ipaq_micro * micro)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
ipaq_micro_tx_msg(struct ipaq_micro * micro,struct ipaq_micro_msg * msg)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
micro_rx_msg(struct ipaq_micro * micro,u8 id,int len,u8 * data)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
micro_process_char(struct ipaq_micro * micro,u8 ch)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
micro_rx_chars(struct ipaq_micro * micro)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
ipaq_micro_get_version(struct ipaq_micro * micro)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
ipaq_micro_eeprom_read(struct ipaq_micro * micro,u8 address,u8 len,u8 * data)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
ipaq_micro_str(u8 * wchar,u8 len)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
ipaq_micro_to_u16(u8 * data)235 static u16 ipaq_micro_to_u16(u8 *data)
236 {
237 return data[1] << 8 | data[0];
238 }
239
ipaq_micro_eeprom_dump(struct ipaq_micro * micro)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
micro_tx_chars(struct ipaq_micro * micro)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
micro_reset_comm(struct ipaq_micro * micro)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
micro_serial_isr(int irq,void * dev_id)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
micro_resume(struct device * dev)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
micro_probe(struct platform_device * pdev)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 res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
400 if (!res)
401 return -EINVAL;
402
403 micro->sdlc = devm_ioremap_resource(&pdev->dev, res);
404 if (IS_ERR(micro->sdlc))
405 return PTR_ERR(micro->sdlc);
406
407 micro_reset_comm(micro);
408
409 irq = platform_get_irq(pdev, 0);
410 if (!irq)
411 return -EINVAL;
412 ret = devm_request_irq(&pdev->dev, irq, micro_serial_isr,
413 IRQF_SHARED, "ipaq-micro",
414 micro);
415 if (ret) {
416 dev_err(&pdev->dev, "unable to grab serial port IRQ\n");
417 return ret;
418 } else
419 dev_info(&pdev->dev, "grabbed serial port IRQ\n");
420
421 spin_lock_init(µ->lock);
422 INIT_LIST_HEAD(µ->queue);
423 platform_set_drvdata(pdev, micro);
424
425 ret = mfd_add_devices(&pdev->dev, pdev->id, micro_cells,
426 ARRAY_SIZE(micro_cells), NULL, 0, NULL);
427 if (ret) {
428 dev_err(&pdev->dev, "error adding MFD cells");
429 return ret;
430 }
431
432 /* Check version */
433 ipaq_micro_get_version(micro);
434 dev_info(&pdev->dev, "Atmel micro ASIC version %s\n", micro->version);
435 ipaq_micro_eeprom_dump(micro);
436
437 return 0;
438 }
439
440 static const struct dev_pm_ops micro_dev_pm_ops = {
441 SET_SYSTEM_SLEEP_PM_OPS(NULL, micro_resume)
442 };
443
444 static struct platform_driver micro_device_driver = {
445 .driver = {
446 .name = "ipaq-h3xxx-micro",
447 .pm = µ_dev_pm_ops,
448 .suppress_bind_attrs = true,
449 },
450 };
451 builtin_platform_driver_probe(micro_device_driver, micro_probe);
452