xref: /openbmc/linux/drivers/sbus/char/uctrl.c (revision 15e3ae36)
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 DEBUG 1
27 #ifdef DEBUG
28 #define dprintk(x) printk x
29 #else
30 #define dprintk(x)
31 #endif
32 
33 struct uctrl_regs {
34 	u32 uctrl_intr;
35 	u32 uctrl_data;
36 	u32 uctrl_stat;
37 	u32 uctrl_xxx[5];
38 };
39 
40 struct ts102_regs {
41 	u32 card_a_intr;
42 	u32 card_a_stat;
43 	u32 card_a_ctrl;
44 	u32 card_a_xxx;
45 	u32 card_b_intr;
46 	u32 card_b_stat;
47 	u32 card_b_ctrl;
48 	u32 card_b_xxx;
49 	u32 uctrl_intr;
50 	u32 uctrl_data;
51 	u32 uctrl_stat;
52 	u32 uctrl_xxx;
53 	u32 ts102_xxx[4];
54 };
55 
56 /* Bits for uctrl_intr register */
57 #define UCTRL_INTR_TXE_REQ         0x01    /* transmit FIFO empty int req */
58 #define UCTRL_INTR_TXNF_REQ        0x02    /* transmit FIFO not full int req */
59 #define UCTRL_INTR_RXNE_REQ        0x04    /* receive FIFO not empty int req */
60 #define UCTRL_INTR_RXO_REQ         0x08    /* receive FIFO overflow int req */
61 #define UCTRL_INTR_TXE_MSK         0x10    /* transmit FIFO empty mask */
62 #define UCTRL_INTR_TXNF_MSK        0x20    /* transmit FIFO not full mask */
63 #define UCTRL_INTR_RXNE_MSK        0x40    /* receive FIFO not empty mask */
64 #define UCTRL_INTR_RXO_MSK         0x80    /* receive FIFO overflow mask */
65 
66 /* Bits for uctrl_stat register */
67 #define UCTRL_STAT_TXE_STA         0x01    /* transmit FIFO empty status */
68 #define UCTRL_STAT_TXNF_STA        0x02    /* transmit FIFO not full status */
69 #define UCTRL_STAT_RXNE_STA        0x04    /* receive FIFO not empty status */
70 #define UCTRL_STAT_RXO_STA         0x08    /* receive FIFO overflow status */
71 
72 static DEFINE_MUTEX(uctrl_mutex);
73 static const char *uctrl_extstatus[16] = {
74         "main power available",
75         "internal battery attached",
76         "external battery attached",
77         "external VGA attached",
78         "external keyboard attached",
79         "external mouse attached",
80         "lid down",
81         "internal battery currently charging",
82         "external battery currently charging",
83         "internal battery currently discharging",
84         "external battery currently discharging",
85 };
86 
87 /* Everything required for one transaction with the uctrl */
88 struct uctrl_txn {
89 	u8 opcode;
90 	u8 inbits;
91 	u8 outbits;
92 	u8 *inbuf;
93 	u8 *outbuf;
94 };
95 
96 struct uctrl_status {
97 	u8 current_temp; /* 0x07 */
98 	u8 reset_status; /* 0x0b */
99 	u16 event_status; /* 0x0c */
100 	u16 error_status; /* 0x10 */
101 	u16 external_status; /* 0x11, 0x1b */
102 	u8 internal_charge; /* 0x18 */
103 	u8 external_charge; /* 0x19 */
104 	u16 control_lcd; /* 0x20 */
105 	u8 control_bitport; /* 0x21 */
106 	u8 speaker_volume; /* 0x23 */
107 	u8 control_tft_brightness; /* 0x24 */
108 	u8 control_kbd_repeat_delay; /* 0x28 */
109 	u8 control_kbd_repeat_period; /* 0x29 */
110 	u8 control_screen_contrast; /* 0x2F */
111 };
112 
113 enum uctrl_opcode {
114   READ_SERIAL_NUMBER=0x1,
115   READ_ETHERNET_ADDRESS=0x2,
116   READ_HARDWARE_VERSION=0x3,
117   READ_MICROCONTROLLER_VERSION=0x4,
118   READ_MAX_TEMPERATURE=0x5,
119   READ_MIN_TEMPERATURE=0x6,
120   READ_CURRENT_TEMPERATURE=0x7,
121   READ_SYSTEM_VARIANT=0x8,
122   READ_POWERON_CYCLES=0x9,
123   READ_POWERON_SECONDS=0xA,
124   READ_RESET_STATUS=0xB,
125   READ_EVENT_STATUS=0xC,
126   READ_REAL_TIME_CLOCK=0xD,
127   READ_EXTERNAL_VGA_PORT=0xE,
128   READ_MICROCONTROLLER_ROM_CHECKSUM=0xF,
129   READ_ERROR_STATUS=0x10,
130   READ_EXTERNAL_STATUS=0x11,
131   READ_USER_CONFIGURATION_AREA=0x12,
132   READ_MICROCONTROLLER_VOLTAGE=0x13,
133   READ_INTERNAL_BATTERY_VOLTAGE=0x14,
134   READ_DCIN_VOLTAGE=0x15,
135   READ_HORIZONTAL_POINTER_VOLTAGE=0x16,
136   READ_VERTICAL_POINTER_VOLTAGE=0x17,
137   READ_INTERNAL_BATTERY_CHARGE_LEVEL=0x18,
138   READ_EXTERNAL_BATTERY_CHARGE_LEVEL=0x19,
139   READ_REAL_TIME_CLOCK_ALARM=0x1A,
140   READ_EVENT_STATUS_NO_RESET=0x1B,
141   READ_INTERNAL_KEYBOARD_LAYOUT=0x1C,
142   READ_EXTERNAL_KEYBOARD_LAYOUT=0x1D,
143   READ_EEPROM_STATUS=0x1E,
144   CONTROL_LCD=0x20,
145   CONTROL_BITPORT=0x21,
146   SPEAKER_VOLUME=0x23,
147   CONTROL_TFT_BRIGHTNESS=0x24,
148   CONTROL_WATCHDOG=0x25,
149   CONTROL_FACTORY_EEPROM_AREA=0x26,
150   CONTROL_KBD_TIME_UNTIL_REPEAT=0x28,
151   CONTROL_KBD_TIME_BETWEEN_REPEATS=0x29,
152   CONTROL_TIMEZONE=0x2A,
153   CONTROL_MARK_SPACE_RATIO=0x2B,
154   CONTROL_DIAGNOSTIC_MODE=0x2E,
155   CONTROL_SCREEN_CONTRAST=0x2F,
156   RING_BELL=0x30,
157   SET_DIAGNOSTIC_STATUS=0x32,
158   CLEAR_KEY_COMBINATION_TABLE=0x33,
159   PERFORM_SOFTWARE_RESET=0x34,
160   SET_REAL_TIME_CLOCK=0x35,
161   RECALIBRATE_POINTING_STICK=0x36,
162   SET_BELL_FREQUENCY=0x37,
163   SET_INTERNAL_BATTERY_CHARGE_RATE=0x39,
164   SET_EXTERNAL_BATTERY_CHARGE_RATE=0x3A,
165   SET_REAL_TIME_CLOCK_ALARM=0x3B,
166   READ_EEPROM=0x40,
167   WRITE_EEPROM=0x41,
168   WRITE_TO_STATUS_DISPLAY=0x42,
169   DEFINE_SPECIAL_CHARACTER=0x43,
170   DEFINE_KEY_COMBINATION_ENTRY=0x50,
171   DEFINE_STRING_TABLE_ENTRY=0x51,
172   DEFINE_STATUS_SCREEN_DISPLAY=0x52,
173   PERFORM_EMU_COMMANDS=0x64,
174   READ_EMU_REGISTER=0x65,
175   WRITE_EMU_REGISTER=0x66,
176   READ_EMU_RAM=0x67,
177   WRITE_EMU_RAM=0x68,
178   READ_BQ_REGISTER=0x69,
179   WRITE_BQ_REGISTER=0x6A,
180   SET_USER_PASSWORD=0x70,
181   VERIFY_USER_PASSWORD=0x71,
182   GET_SYSTEM_PASSWORD_KEY=0x72,
183   VERIFY_SYSTEM_PASSWORD=0x73,
184   POWER_OFF=0x82,
185   POWER_RESTART=0x83,
186 };
187 
188 static struct uctrl_driver {
189 	struct uctrl_regs __iomem *regs;
190 	int irq;
191 	int pending;
192 	struct uctrl_status status;
193 } *global_driver;
194 
195 static void uctrl_get_event_status(struct uctrl_driver *);
196 static void uctrl_get_external_status(struct uctrl_driver *);
197 
198 static long
199 uctrl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
200 {
201 	switch (cmd) {
202 		default:
203 			return -EINVAL;
204 	}
205 	return 0;
206 }
207 
208 static int
209 uctrl_open(struct inode *inode, struct file *file)
210 {
211 	mutex_lock(&uctrl_mutex);
212 	uctrl_get_event_status(global_driver);
213 	uctrl_get_external_status(global_driver);
214 	mutex_unlock(&uctrl_mutex);
215 	return 0;
216 }
217 
218 static irqreturn_t uctrl_interrupt(int irq, void *dev_id)
219 {
220 	return IRQ_HANDLED;
221 }
222 
223 static const struct file_operations uctrl_fops = {
224 	.owner =	THIS_MODULE,
225 	.llseek =	no_llseek,
226 	.unlocked_ioctl =	uctrl_ioctl,
227 	.open =		uctrl_open,
228 };
229 
230 static struct miscdevice uctrl_dev = {
231 	UCTRL_MINOR,
232 	"uctrl",
233 	&uctrl_fops
234 };
235 
236 /* Wait for space to write, then write to it */
237 #define WRITEUCTLDATA(value) \
238 { \
239   unsigned int i; \
240   for (i = 0; i < 10000; i++) { \
241       if (UCTRL_STAT_TXNF_STA & sbus_readl(&driver->regs->uctrl_stat)) \
242       break; \
243   } \
244   dprintk(("write data 0x%02x\n", value)); \
245   sbus_writel(value, &driver->regs->uctrl_data); \
246 }
247 
248 /* Wait for something to read, read it, then clear the bit */
249 #define READUCTLDATA(value) \
250 { \
251   unsigned int i; \
252   value = 0; \
253   for (i = 0; i < 10000; i++) { \
254       if ((UCTRL_STAT_RXNE_STA & sbus_readl(&driver->regs->uctrl_stat)) == 0) \
255       break; \
256     udelay(1); \
257   } \
258   value = sbus_readl(&driver->regs->uctrl_data); \
259   dprintk(("read data 0x%02x\n", value)); \
260   sbus_writel(UCTRL_STAT_RXNE_STA, &driver->regs->uctrl_stat); \
261 }
262 
263 static void uctrl_do_txn(struct uctrl_driver *driver, struct uctrl_txn *txn)
264 {
265 	int stat, incnt, outcnt, bytecnt, intr;
266 	u32 byte;
267 
268 	stat = sbus_readl(&driver->regs->uctrl_stat);
269 	intr = sbus_readl(&driver->regs->uctrl_intr);
270 	sbus_writel(stat, &driver->regs->uctrl_stat);
271 
272 	dprintk(("interrupt stat 0x%x int 0x%x\n", stat, intr));
273 
274 	incnt = txn->inbits;
275 	outcnt = txn->outbits;
276 	byte = (txn->opcode << 8);
277 	WRITEUCTLDATA(byte);
278 
279 	bytecnt = 0;
280 	while (incnt > 0) {
281 		byte = (txn->inbuf[bytecnt] << 8);
282 		WRITEUCTLDATA(byte);
283 		incnt--;
284 		bytecnt++;
285 	}
286 
287 	/* Get the ack */
288 	READUCTLDATA(byte);
289 	dprintk(("ack was %x\n", (byte >> 8)));
290 
291 	bytecnt = 0;
292 	while (outcnt > 0) {
293 		READUCTLDATA(byte);
294 		txn->outbuf[bytecnt] = (byte >> 8);
295 		dprintk(("set byte to %02x\n", byte));
296 		outcnt--;
297 		bytecnt++;
298 	}
299 }
300 
301 static void uctrl_get_event_status(struct uctrl_driver *driver)
302 {
303 	struct uctrl_txn txn;
304 	u8 outbits[2];
305 
306 	txn.opcode = READ_EVENT_STATUS;
307 	txn.inbits = 0;
308 	txn.outbits = 2;
309 	txn.inbuf = NULL;
310 	txn.outbuf = outbits;
311 
312 	uctrl_do_txn(driver, &txn);
313 
314 	dprintk(("bytes %x %x\n", (outbits[0] & 0xff), (outbits[1] & 0xff)));
315 	driver->status.event_status =
316 		((outbits[0] & 0xff) << 8) | (outbits[1] & 0xff);
317 	dprintk(("ev is %x\n", driver->status.event_status));
318 }
319 
320 static void uctrl_get_external_status(struct uctrl_driver *driver)
321 {
322 	struct uctrl_txn txn;
323 	u8 outbits[2];
324 	int i, v;
325 
326 	txn.opcode = READ_EXTERNAL_STATUS;
327 	txn.inbits = 0;
328 	txn.outbits = 2;
329 	txn.inbuf = NULL;
330 	txn.outbuf = outbits;
331 
332 	uctrl_do_txn(driver, &txn);
333 
334 	dprintk(("bytes %x %x\n", (outbits[0] & 0xff), (outbits[1] & 0xff)));
335 	driver->status.external_status =
336 		((outbits[0] * 256) + (outbits[1]));
337 	dprintk(("ex is %x\n", driver->status.external_status));
338 	v = driver->status.external_status;
339 	for (i = 0; v != 0; i++, v >>= 1) {
340 		if (v & 1) {
341 			dprintk(("%s%s", " ", uctrl_extstatus[i]));
342 		}
343 	}
344 	dprintk(("\n"));
345 
346 }
347 
348 static int uctrl_probe(struct platform_device *op)
349 {
350 	struct uctrl_driver *p;
351 	int err = -ENOMEM;
352 
353 	p = kzalloc(sizeof(*p), GFP_KERNEL);
354 	if (!p) {
355 		printk(KERN_ERR "uctrl: Unable to allocate device struct.\n");
356 		goto out;
357 	}
358 
359 	p->regs = of_ioremap(&op->resource[0], 0,
360 			     resource_size(&op->resource[0]),
361 			     "uctrl");
362 	if (!p->regs) {
363 		printk(KERN_ERR "uctrl: Unable to map registers.\n");
364 		goto out_free;
365 	}
366 
367 	p->irq = op->archdata.irqs[0];
368 	err = request_irq(p->irq, uctrl_interrupt, 0, "uctrl", p);
369 	if (err) {
370 		printk(KERN_ERR "uctrl: Unable to register irq.\n");
371 		goto out_iounmap;
372 	}
373 
374 	err = misc_register(&uctrl_dev);
375 	if (err) {
376 		printk(KERN_ERR "uctrl: Unable to register misc device.\n");
377 		goto out_free_irq;
378 	}
379 
380 	sbus_writel(UCTRL_INTR_RXNE_REQ|UCTRL_INTR_RXNE_MSK, &p->regs->uctrl_intr);
381 	printk(KERN_INFO "%pOF: uctrl regs[0x%p] (irq %d)\n",
382 	       op->dev.of_node, p->regs, p->irq);
383 	uctrl_get_event_status(p);
384 	uctrl_get_external_status(p);
385 
386 	dev_set_drvdata(&op->dev, p);
387 	global_driver = p;
388 
389 out:
390 	return err;
391 
392 out_free_irq:
393 	free_irq(p->irq, p);
394 
395 out_iounmap:
396 	of_iounmap(&op->resource[0], p->regs, resource_size(&op->resource[0]));
397 
398 out_free:
399 	kfree(p);
400 	goto out;
401 }
402 
403 static int uctrl_remove(struct platform_device *op)
404 {
405 	struct uctrl_driver *p = dev_get_drvdata(&op->dev);
406 
407 	if (p) {
408 		misc_deregister(&uctrl_dev);
409 		free_irq(p->irq, p);
410 		of_iounmap(&op->resource[0], p->regs, resource_size(&op->resource[0]));
411 		kfree(p);
412 	}
413 	return 0;
414 }
415 
416 static const struct of_device_id uctrl_match[] = {
417 	{
418 		.name = "uctrl",
419 	},
420 	{},
421 };
422 MODULE_DEVICE_TABLE(of, uctrl_match);
423 
424 static struct platform_driver uctrl_driver = {
425 	.driver = {
426 		.name = "uctrl",
427 		.of_match_table = uctrl_match,
428 	},
429 	.probe		= uctrl_probe,
430 	.remove		= uctrl_remove,
431 };
432 
433 
434 module_platform_driver(uctrl_driver);
435 
436 MODULE_LICENSE("GPL");
437