xref: /openbmc/linux/drivers/sbus/char/uctrl.c (revision a44e4f3a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* uctrl.c: TS102 Microcontroller interface on Tadpole Sparcbook 3
3  *
4  * Copyright 1999 Derrick J Brashear (shadow@dementia.org)
5  * Copyright 2008 David S. Miller (davem@davemloft.net)
6  */
7 
8 #include <linux/module.h>
9 #include <linux/errno.h>
10 #include <linux/delay.h>
11 #include <linux/interrupt.h>
12 #include <linux/slab.h>
13 #include <linux/mutex.h>
14 #include <linux/ioport.h>
15 #include <linux/miscdevice.h>
16 #include <linux/mm.h>
17 #include <linux/of.h>
18 #include <linux/of_device.h>
19 
20 #include <asm/openprom.h>
21 #include <asm/oplib.h>
22 #include <asm/irq.h>
23 #include <asm/io.h>
24 #include <asm/pgtable.h>
25 
26 #define UCTRL_MINOR	174
27 
28 #define DEBUG 1
29 #ifdef DEBUG
30 #define dprintk(x) printk x
31 #else
32 #define dprintk(x)
33 #endif
34 
35 struct uctrl_regs {
36 	u32 uctrl_intr;
37 	u32 uctrl_data;
38 	u32 uctrl_stat;
39 	u32 uctrl_xxx[5];
40 };
41 
42 struct ts102_regs {
43 	u32 card_a_intr;
44 	u32 card_a_stat;
45 	u32 card_a_ctrl;
46 	u32 card_a_xxx;
47 	u32 card_b_intr;
48 	u32 card_b_stat;
49 	u32 card_b_ctrl;
50 	u32 card_b_xxx;
51 	u32 uctrl_intr;
52 	u32 uctrl_data;
53 	u32 uctrl_stat;
54 	u32 uctrl_xxx;
55 	u32 ts102_xxx[4];
56 };
57 
58 /* Bits for uctrl_intr register */
59 #define UCTRL_INTR_TXE_REQ         0x01    /* transmit FIFO empty int req */
60 #define UCTRL_INTR_TXNF_REQ        0x02    /* transmit FIFO not full int req */
61 #define UCTRL_INTR_RXNE_REQ        0x04    /* receive FIFO not empty int req */
62 #define UCTRL_INTR_RXO_REQ         0x08    /* receive FIFO overflow int req */
63 #define UCTRL_INTR_TXE_MSK         0x10    /* transmit FIFO empty mask */
64 #define UCTRL_INTR_TXNF_MSK        0x20    /* transmit FIFO not full mask */
65 #define UCTRL_INTR_RXNE_MSK        0x40    /* receive FIFO not empty mask */
66 #define UCTRL_INTR_RXO_MSK         0x80    /* receive FIFO overflow mask */
67 
68 /* Bits for uctrl_stat register */
69 #define UCTRL_STAT_TXE_STA         0x01    /* transmit FIFO empty status */
70 #define UCTRL_STAT_TXNF_STA        0x02    /* transmit FIFO not full status */
71 #define UCTRL_STAT_RXNE_STA        0x04    /* receive FIFO not empty status */
72 #define UCTRL_STAT_RXO_STA         0x08    /* receive FIFO overflow status */
73 
74 static DEFINE_MUTEX(uctrl_mutex);
75 static const char *uctrl_extstatus[16] = {
76         "main power available",
77         "internal battery attached",
78         "external battery attached",
79         "external VGA attached",
80         "external keyboard attached",
81         "external mouse attached",
82         "lid down",
83         "internal battery currently charging",
84         "external battery currently charging",
85         "internal battery currently discharging",
86         "external battery currently discharging",
87 };
88 
89 /* Everything required for one transaction with the uctrl */
90 struct uctrl_txn {
91 	u8 opcode;
92 	u8 inbits;
93 	u8 outbits;
94 	u8 *inbuf;
95 	u8 *outbuf;
96 };
97 
98 struct uctrl_status {
99 	u8 current_temp; /* 0x07 */
100 	u8 reset_status; /* 0x0b */
101 	u16 event_status; /* 0x0c */
102 	u16 error_status; /* 0x10 */
103 	u16 external_status; /* 0x11, 0x1b */
104 	u8 internal_charge; /* 0x18 */
105 	u8 external_charge; /* 0x19 */
106 	u16 control_lcd; /* 0x20 */
107 	u8 control_bitport; /* 0x21 */
108 	u8 speaker_volume; /* 0x23 */
109 	u8 control_tft_brightness; /* 0x24 */
110 	u8 control_kbd_repeat_delay; /* 0x28 */
111 	u8 control_kbd_repeat_period; /* 0x29 */
112 	u8 control_screen_contrast; /* 0x2F */
113 };
114 
115 enum uctrl_opcode {
116   READ_SERIAL_NUMBER=0x1,
117   READ_ETHERNET_ADDRESS=0x2,
118   READ_HARDWARE_VERSION=0x3,
119   READ_MICROCONTROLLER_VERSION=0x4,
120   READ_MAX_TEMPERATURE=0x5,
121   READ_MIN_TEMPERATURE=0x6,
122   READ_CURRENT_TEMPERATURE=0x7,
123   READ_SYSTEM_VARIANT=0x8,
124   READ_POWERON_CYCLES=0x9,
125   READ_POWERON_SECONDS=0xA,
126   READ_RESET_STATUS=0xB,
127   READ_EVENT_STATUS=0xC,
128   READ_REAL_TIME_CLOCK=0xD,
129   READ_EXTERNAL_VGA_PORT=0xE,
130   READ_MICROCONTROLLER_ROM_CHECKSUM=0xF,
131   READ_ERROR_STATUS=0x10,
132   READ_EXTERNAL_STATUS=0x11,
133   READ_USER_CONFIGURATION_AREA=0x12,
134   READ_MICROCONTROLLER_VOLTAGE=0x13,
135   READ_INTERNAL_BATTERY_VOLTAGE=0x14,
136   READ_DCIN_VOLTAGE=0x15,
137   READ_HORIZONTAL_POINTER_VOLTAGE=0x16,
138   READ_VERTICAL_POINTER_VOLTAGE=0x17,
139   READ_INTERNAL_BATTERY_CHARGE_LEVEL=0x18,
140   READ_EXTERNAL_BATTERY_CHARGE_LEVEL=0x19,
141   READ_REAL_TIME_CLOCK_ALARM=0x1A,
142   READ_EVENT_STATUS_NO_RESET=0x1B,
143   READ_INTERNAL_KEYBOARD_LAYOUT=0x1C,
144   READ_EXTERNAL_KEYBOARD_LAYOUT=0x1D,
145   READ_EEPROM_STATUS=0x1E,
146   CONTROL_LCD=0x20,
147   CONTROL_BITPORT=0x21,
148   SPEAKER_VOLUME=0x23,
149   CONTROL_TFT_BRIGHTNESS=0x24,
150   CONTROL_WATCHDOG=0x25,
151   CONTROL_FACTORY_EEPROM_AREA=0x26,
152   CONTROL_KBD_TIME_UNTIL_REPEAT=0x28,
153   CONTROL_KBD_TIME_BETWEEN_REPEATS=0x29,
154   CONTROL_TIMEZONE=0x2A,
155   CONTROL_MARK_SPACE_RATIO=0x2B,
156   CONTROL_DIAGNOSTIC_MODE=0x2E,
157   CONTROL_SCREEN_CONTRAST=0x2F,
158   RING_BELL=0x30,
159   SET_DIAGNOSTIC_STATUS=0x32,
160   CLEAR_KEY_COMBINATION_TABLE=0x33,
161   PERFORM_SOFTWARE_RESET=0x34,
162   SET_REAL_TIME_CLOCK=0x35,
163   RECALIBRATE_POINTING_STICK=0x36,
164   SET_BELL_FREQUENCY=0x37,
165   SET_INTERNAL_BATTERY_CHARGE_RATE=0x39,
166   SET_EXTERNAL_BATTERY_CHARGE_RATE=0x3A,
167   SET_REAL_TIME_CLOCK_ALARM=0x3B,
168   READ_EEPROM=0x40,
169   WRITE_EEPROM=0x41,
170   WRITE_TO_STATUS_DISPLAY=0x42,
171   DEFINE_SPECIAL_CHARACTER=0x43,
172   DEFINE_KEY_COMBINATION_ENTRY=0x50,
173   DEFINE_STRING_TABLE_ENTRY=0x51,
174   DEFINE_STATUS_SCREEN_DISPLAY=0x52,
175   PERFORM_EMU_COMMANDS=0x64,
176   READ_EMU_REGISTER=0x65,
177   WRITE_EMU_REGISTER=0x66,
178   READ_EMU_RAM=0x67,
179   WRITE_EMU_RAM=0x68,
180   READ_BQ_REGISTER=0x69,
181   WRITE_BQ_REGISTER=0x6A,
182   SET_USER_PASSWORD=0x70,
183   VERIFY_USER_PASSWORD=0x71,
184   GET_SYSTEM_PASSWORD_KEY=0x72,
185   VERIFY_SYSTEM_PASSWORD=0x73,
186   POWER_OFF=0x82,
187   POWER_RESTART=0x83,
188 };
189 
190 static struct uctrl_driver {
191 	struct uctrl_regs __iomem *regs;
192 	int irq;
193 	int pending;
194 	struct uctrl_status status;
195 } *global_driver;
196 
197 static void uctrl_get_event_status(struct uctrl_driver *);
198 static void uctrl_get_external_status(struct uctrl_driver *);
199 
200 static long
201 uctrl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
202 {
203 	switch (cmd) {
204 		default:
205 			return -EINVAL;
206 	}
207 	return 0;
208 }
209 
210 static int
211 uctrl_open(struct inode *inode, struct file *file)
212 {
213 	mutex_lock(&uctrl_mutex);
214 	uctrl_get_event_status(global_driver);
215 	uctrl_get_external_status(global_driver);
216 	mutex_unlock(&uctrl_mutex);
217 	return 0;
218 }
219 
220 static irqreturn_t uctrl_interrupt(int irq, void *dev_id)
221 {
222 	return IRQ_HANDLED;
223 }
224 
225 static const struct file_operations uctrl_fops = {
226 	.owner =	THIS_MODULE,
227 	.llseek =	no_llseek,
228 	.unlocked_ioctl =	uctrl_ioctl,
229 	.open =		uctrl_open,
230 };
231 
232 static struct miscdevice uctrl_dev = {
233 	UCTRL_MINOR,
234 	"uctrl",
235 	&uctrl_fops
236 };
237 
238 /* Wait for space to write, then write to it */
239 #define WRITEUCTLDATA(value) \
240 { \
241   unsigned int i; \
242   for (i = 0; i < 10000; i++) { \
243       if (UCTRL_STAT_TXNF_STA & sbus_readl(&driver->regs->uctrl_stat)) \
244       break; \
245   } \
246   dprintk(("write data 0x%02x\n", value)); \
247   sbus_writel(value, &driver->regs->uctrl_data); \
248 }
249 
250 /* Wait for something to read, read it, then clear the bit */
251 #define READUCTLDATA(value) \
252 { \
253   unsigned int i; \
254   value = 0; \
255   for (i = 0; i < 10000; i++) { \
256       if ((UCTRL_STAT_RXNE_STA & sbus_readl(&driver->regs->uctrl_stat)) == 0) \
257       break; \
258     udelay(1); \
259   } \
260   value = sbus_readl(&driver->regs->uctrl_data); \
261   dprintk(("read data 0x%02x\n", value)); \
262   sbus_writel(UCTRL_STAT_RXNE_STA, &driver->regs->uctrl_stat); \
263 }
264 
265 static void uctrl_do_txn(struct uctrl_driver *driver, struct uctrl_txn *txn)
266 {
267 	int stat, incnt, outcnt, bytecnt, intr;
268 	u32 byte;
269 
270 	stat = sbus_readl(&driver->regs->uctrl_stat);
271 	intr = sbus_readl(&driver->regs->uctrl_intr);
272 	sbus_writel(stat, &driver->regs->uctrl_stat);
273 
274 	dprintk(("interrupt stat 0x%x int 0x%x\n", stat, intr));
275 
276 	incnt = txn->inbits;
277 	outcnt = txn->outbits;
278 	byte = (txn->opcode << 8);
279 	WRITEUCTLDATA(byte);
280 
281 	bytecnt = 0;
282 	while (incnt > 0) {
283 		byte = (txn->inbuf[bytecnt] << 8);
284 		WRITEUCTLDATA(byte);
285 		incnt--;
286 		bytecnt++;
287 	}
288 
289 	/* Get the ack */
290 	READUCTLDATA(byte);
291 	dprintk(("ack was %x\n", (byte >> 8)));
292 
293 	bytecnt = 0;
294 	while (outcnt > 0) {
295 		READUCTLDATA(byte);
296 		txn->outbuf[bytecnt] = (byte >> 8);
297 		dprintk(("set byte to %02x\n", byte));
298 		outcnt--;
299 		bytecnt++;
300 	}
301 }
302 
303 static void uctrl_get_event_status(struct uctrl_driver *driver)
304 {
305 	struct uctrl_txn txn;
306 	u8 outbits[2];
307 
308 	txn.opcode = READ_EVENT_STATUS;
309 	txn.inbits = 0;
310 	txn.outbits = 2;
311 	txn.inbuf = NULL;
312 	txn.outbuf = outbits;
313 
314 	uctrl_do_txn(driver, &txn);
315 
316 	dprintk(("bytes %x %x\n", (outbits[0] & 0xff), (outbits[1] & 0xff)));
317 	driver->status.event_status =
318 		((outbits[0] & 0xff) << 8) | (outbits[1] & 0xff);
319 	dprintk(("ev is %x\n", driver->status.event_status));
320 }
321 
322 static void uctrl_get_external_status(struct uctrl_driver *driver)
323 {
324 	struct uctrl_txn txn;
325 	u8 outbits[2];
326 	int i, v;
327 
328 	txn.opcode = READ_EXTERNAL_STATUS;
329 	txn.inbits = 0;
330 	txn.outbits = 2;
331 	txn.inbuf = NULL;
332 	txn.outbuf = outbits;
333 
334 	uctrl_do_txn(driver, &txn);
335 
336 	dprintk(("bytes %x %x\n", (outbits[0] & 0xff), (outbits[1] & 0xff)));
337 	driver->status.external_status =
338 		((outbits[0] * 256) + (outbits[1]));
339 	dprintk(("ex is %x\n", driver->status.external_status));
340 	v = driver->status.external_status;
341 	for (i = 0; v != 0; i++, v >>= 1) {
342 		if (v & 1) {
343 			dprintk(("%s%s", " ", uctrl_extstatus[i]));
344 		}
345 	}
346 	dprintk(("\n"));
347 
348 }
349 
350 static int uctrl_probe(struct platform_device *op)
351 {
352 	struct uctrl_driver *p;
353 	int err = -ENOMEM;
354 
355 	p = kzalloc(sizeof(*p), GFP_KERNEL);
356 	if (!p) {
357 		printk(KERN_ERR "uctrl: Unable to allocate device struct.\n");
358 		goto out;
359 	}
360 
361 	p->regs = of_ioremap(&op->resource[0], 0,
362 			     resource_size(&op->resource[0]),
363 			     "uctrl");
364 	if (!p->regs) {
365 		printk(KERN_ERR "uctrl: Unable to map registers.\n");
366 		goto out_free;
367 	}
368 
369 	p->irq = op->archdata.irqs[0];
370 	err = request_irq(p->irq, uctrl_interrupt, 0, "uctrl", p);
371 	if (err) {
372 		printk(KERN_ERR "uctrl: Unable to register irq.\n");
373 		goto out_iounmap;
374 	}
375 
376 	err = misc_register(&uctrl_dev);
377 	if (err) {
378 		printk(KERN_ERR "uctrl: Unable to register misc device.\n");
379 		goto out_free_irq;
380 	}
381 
382 	sbus_writel(UCTRL_INTR_RXNE_REQ|UCTRL_INTR_RXNE_MSK, &p->regs->uctrl_intr);
383 	printk(KERN_INFO "%pOF: uctrl regs[0x%p] (irq %d)\n",
384 	       op->dev.of_node, p->regs, p->irq);
385 	uctrl_get_event_status(p);
386 	uctrl_get_external_status(p);
387 
388 	dev_set_drvdata(&op->dev, p);
389 	global_driver = p;
390 
391 out:
392 	return err;
393 
394 out_free_irq:
395 	free_irq(p->irq, p);
396 
397 out_iounmap:
398 	of_iounmap(&op->resource[0], p->regs, resource_size(&op->resource[0]));
399 
400 out_free:
401 	kfree(p);
402 	goto out;
403 }
404 
405 static int uctrl_remove(struct platform_device *op)
406 {
407 	struct uctrl_driver *p = dev_get_drvdata(&op->dev);
408 
409 	if (p) {
410 		misc_deregister(&uctrl_dev);
411 		free_irq(p->irq, p);
412 		of_iounmap(&op->resource[0], p->regs, resource_size(&op->resource[0]));
413 		kfree(p);
414 	}
415 	return 0;
416 }
417 
418 static const struct of_device_id uctrl_match[] = {
419 	{
420 		.name = "uctrl",
421 	},
422 	{},
423 };
424 MODULE_DEVICE_TABLE(of, uctrl_match);
425 
426 static struct platform_driver uctrl_driver = {
427 	.driver = {
428 		.name = "uctrl",
429 		.of_match_table = uctrl_match,
430 	},
431 	.probe		= uctrl_probe,
432 	.remove		= uctrl_remove,
433 };
434 
435 
436 module_platform_driver(uctrl_driver);
437 
438 MODULE_LICENSE("GPL");
439