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