xref: /openbmc/linux/drivers/sbus/char/uctrl.c (revision 842ed298)
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 
25 #define DEBUG 1
26 #ifdef DEBUG
27 #define dprintk(x) printk x
28 #else
29 #define dprintk(x)
30 #endif
31 
32 struct uctrl_regs {
33 	u32 uctrl_intr;
34 	u32 uctrl_data;
35 	u32 uctrl_stat;
36 	u32 uctrl_xxx[5];
37 };
38 
39 struct ts102_regs {
40 	u32 card_a_intr;
41 	u32 card_a_stat;
42 	u32 card_a_ctrl;
43 	u32 card_a_xxx;
44 	u32 card_b_intr;
45 	u32 card_b_stat;
46 	u32 card_b_ctrl;
47 	u32 card_b_xxx;
48 	u32 uctrl_intr;
49 	u32 uctrl_data;
50 	u32 uctrl_stat;
51 	u32 uctrl_xxx;
52 	u32 ts102_xxx[4];
53 };
54 
55 /* Bits for uctrl_intr register */
56 #define UCTRL_INTR_TXE_REQ         0x01    /* transmit FIFO empty int req */
57 #define UCTRL_INTR_TXNF_REQ        0x02    /* transmit FIFO not full int req */
58 #define UCTRL_INTR_RXNE_REQ        0x04    /* receive FIFO not empty int req */
59 #define UCTRL_INTR_RXO_REQ         0x08    /* receive FIFO overflow int req */
60 #define UCTRL_INTR_TXE_MSK         0x10    /* transmit FIFO empty mask */
61 #define UCTRL_INTR_TXNF_MSK        0x20    /* transmit FIFO not full mask */
62 #define UCTRL_INTR_RXNE_MSK        0x40    /* receive FIFO not empty mask */
63 #define UCTRL_INTR_RXO_MSK         0x80    /* receive FIFO overflow mask */
64 
65 /* Bits for uctrl_stat register */
66 #define UCTRL_STAT_TXE_STA         0x01    /* transmit FIFO empty status */
67 #define UCTRL_STAT_TXNF_STA        0x02    /* transmit FIFO not full status */
68 #define UCTRL_STAT_RXNE_STA        0x04    /* receive FIFO not empty status */
69 #define UCTRL_STAT_RXO_STA         0x08    /* receive FIFO overflow status */
70 
71 static DEFINE_MUTEX(uctrl_mutex);
72 static const char *uctrl_extstatus[16] = {
73         "main power available",
74         "internal battery attached",
75         "external battery attached",
76         "external VGA attached",
77         "external keyboard attached",
78         "external mouse attached",
79         "lid down",
80         "internal battery currently charging",
81         "external battery currently charging",
82         "internal battery currently discharging",
83         "external battery currently discharging",
84 };
85 
86 /* Everything required for one transaction with the uctrl */
87 struct uctrl_txn {
88 	u8 opcode;
89 	u8 inbits;
90 	u8 outbits;
91 	u8 *inbuf;
92 	u8 *outbuf;
93 };
94 
95 struct uctrl_status {
96 	u8 current_temp; /* 0x07 */
97 	u8 reset_status; /* 0x0b */
98 	u16 event_status; /* 0x0c */
99 	u16 error_status; /* 0x10 */
100 	u16 external_status; /* 0x11, 0x1b */
101 	u8 internal_charge; /* 0x18 */
102 	u8 external_charge; /* 0x19 */
103 	u16 control_lcd; /* 0x20 */
104 	u8 control_bitport; /* 0x21 */
105 	u8 speaker_volume; /* 0x23 */
106 	u8 control_tft_brightness; /* 0x24 */
107 	u8 control_kbd_repeat_delay; /* 0x28 */
108 	u8 control_kbd_repeat_period; /* 0x29 */
109 	u8 control_screen_contrast; /* 0x2F */
110 };
111 
112 enum uctrl_opcode {
113   READ_SERIAL_NUMBER=0x1,
114   READ_ETHERNET_ADDRESS=0x2,
115   READ_HARDWARE_VERSION=0x3,
116   READ_MICROCONTROLLER_VERSION=0x4,
117   READ_MAX_TEMPERATURE=0x5,
118   READ_MIN_TEMPERATURE=0x6,
119   READ_CURRENT_TEMPERATURE=0x7,
120   READ_SYSTEM_VARIANT=0x8,
121   READ_POWERON_CYCLES=0x9,
122   READ_POWERON_SECONDS=0xA,
123   READ_RESET_STATUS=0xB,
124   READ_EVENT_STATUS=0xC,
125   READ_REAL_TIME_CLOCK=0xD,
126   READ_EXTERNAL_VGA_PORT=0xE,
127   READ_MICROCONTROLLER_ROM_CHECKSUM=0xF,
128   READ_ERROR_STATUS=0x10,
129   READ_EXTERNAL_STATUS=0x11,
130   READ_USER_CONFIGURATION_AREA=0x12,
131   READ_MICROCONTROLLER_VOLTAGE=0x13,
132   READ_INTERNAL_BATTERY_VOLTAGE=0x14,
133   READ_DCIN_VOLTAGE=0x15,
134   READ_HORIZONTAL_POINTER_VOLTAGE=0x16,
135   READ_VERTICAL_POINTER_VOLTAGE=0x17,
136   READ_INTERNAL_BATTERY_CHARGE_LEVEL=0x18,
137   READ_EXTERNAL_BATTERY_CHARGE_LEVEL=0x19,
138   READ_REAL_TIME_CLOCK_ALARM=0x1A,
139   READ_EVENT_STATUS_NO_RESET=0x1B,
140   READ_INTERNAL_KEYBOARD_LAYOUT=0x1C,
141   READ_EXTERNAL_KEYBOARD_LAYOUT=0x1D,
142   READ_EEPROM_STATUS=0x1E,
143   CONTROL_LCD=0x20,
144   CONTROL_BITPORT=0x21,
145   SPEAKER_VOLUME=0x23,
146   CONTROL_TFT_BRIGHTNESS=0x24,
147   CONTROL_WATCHDOG=0x25,
148   CONTROL_FACTORY_EEPROM_AREA=0x26,
149   CONTROL_KBD_TIME_UNTIL_REPEAT=0x28,
150   CONTROL_KBD_TIME_BETWEEN_REPEATS=0x29,
151   CONTROL_TIMEZONE=0x2A,
152   CONTROL_MARK_SPACE_RATIO=0x2B,
153   CONTROL_DIAGNOSTIC_MODE=0x2E,
154   CONTROL_SCREEN_CONTRAST=0x2F,
155   RING_BELL=0x30,
156   SET_DIAGNOSTIC_STATUS=0x32,
157   CLEAR_KEY_COMBINATION_TABLE=0x33,
158   PERFORM_SOFTWARE_RESET=0x34,
159   SET_REAL_TIME_CLOCK=0x35,
160   RECALIBRATE_POINTING_STICK=0x36,
161   SET_BELL_FREQUENCY=0x37,
162   SET_INTERNAL_BATTERY_CHARGE_RATE=0x39,
163   SET_EXTERNAL_BATTERY_CHARGE_RATE=0x3A,
164   SET_REAL_TIME_CLOCK_ALARM=0x3B,
165   READ_EEPROM=0x40,
166   WRITE_EEPROM=0x41,
167   WRITE_TO_STATUS_DISPLAY=0x42,
168   DEFINE_SPECIAL_CHARACTER=0x43,
169   DEFINE_KEY_COMBINATION_ENTRY=0x50,
170   DEFINE_STRING_TABLE_ENTRY=0x51,
171   DEFINE_STATUS_SCREEN_DISPLAY=0x52,
172   PERFORM_EMU_COMMANDS=0x64,
173   READ_EMU_REGISTER=0x65,
174   WRITE_EMU_REGISTER=0x66,
175   READ_EMU_RAM=0x67,
176   WRITE_EMU_RAM=0x68,
177   READ_BQ_REGISTER=0x69,
178   WRITE_BQ_REGISTER=0x6A,
179   SET_USER_PASSWORD=0x70,
180   VERIFY_USER_PASSWORD=0x71,
181   GET_SYSTEM_PASSWORD_KEY=0x72,
182   VERIFY_SYSTEM_PASSWORD=0x73,
183   POWER_OFF=0x82,
184   POWER_RESTART=0x83,
185 };
186 
187 static struct uctrl_driver {
188 	struct uctrl_regs __iomem *regs;
189 	int irq;
190 	int pending;
191 	struct uctrl_status status;
192 } *global_driver;
193 
194 static void uctrl_get_event_status(struct uctrl_driver *);
195 static void uctrl_get_external_status(struct uctrl_driver *);
196 
197 static long
198 uctrl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
199 {
200 	switch (cmd) {
201 		default:
202 			return -EINVAL;
203 	}
204 	return 0;
205 }
206 
207 static int
208 uctrl_open(struct inode *inode, struct file *file)
209 {
210 	mutex_lock(&uctrl_mutex);
211 	uctrl_get_event_status(global_driver);
212 	uctrl_get_external_status(global_driver);
213 	mutex_unlock(&uctrl_mutex);
214 	return 0;
215 }
216 
217 static irqreturn_t uctrl_interrupt(int irq, void *dev_id)
218 {
219 	return IRQ_HANDLED;
220 }
221 
222 static const struct file_operations uctrl_fops = {
223 	.owner =	THIS_MODULE,
224 	.llseek =	no_llseek,
225 	.unlocked_ioctl =	uctrl_ioctl,
226 	.open =		uctrl_open,
227 };
228 
229 static struct miscdevice uctrl_dev = {
230 	UCTRL_MINOR,
231 	"uctrl",
232 	&uctrl_fops
233 };
234 
235 /* Wait for space to write, then write to it */
236 #define WRITEUCTLDATA(value) \
237 { \
238   unsigned int i; \
239   for (i = 0; i < 10000; i++) { \
240       if (UCTRL_STAT_TXNF_STA & sbus_readl(&driver->regs->uctrl_stat)) \
241       break; \
242   } \
243   dprintk(("write data 0x%02x\n", value)); \
244   sbus_writel(value, &driver->regs->uctrl_data); \
245 }
246 
247 /* Wait for something to read, read it, then clear the bit */
248 #define READUCTLDATA(value) \
249 { \
250   unsigned int i; \
251   value = 0; \
252   for (i = 0; i < 10000; i++) { \
253       if ((UCTRL_STAT_RXNE_STA & sbus_readl(&driver->regs->uctrl_stat)) == 0) \
254       break; \
255     udelay(1); \
256   } \
257   value = sbus_readl(&driver->regs->uctrl_data); \
258   dprintk(("read data 0x%02x\n", value)); \
259   sbus_writel(UCTRL_STAT_RXNE_STA, &driver->regs->uctrl_stat); \
260 }
261 
262 static void uctrl_do_txn(struct uctrl_driver *driver, struct uctrl_txn *txn)
263 {
264 	int stat, incnt, outcnt, bytecnt, intr;
265 	u32 byte;
266 
267 	stat = sbus_readl(&driver->regs->uctrl_stat);
268 	intr = sbus_readl(&driver->regs->uctrl_intr);
269 	sbus_writel(stat, &driver->regs->uctrl_stat);
270 
271 	dprintk(("interrupt stat 0x%x int 0x%x\n", stat, intr));
272 
273 	incnt = txn->inbits;
274 	outcnt = txn->outbits;
275 	byte = (txn->opcode << 8);
276 	WRITEUCTLDATA(byte);
277 
278 	bytecnt = 0;
279 	while (incnt > 0) {
280 		byte = (txn->inbuf[bytecnt] << 8);
281 		WRITEUCTLDATA(byte);
282 		incnt--;
283 		bytecnt++;
284 	}
285 
286 	/* Get the ack */
287 	READUCTLDATA(byte);
288 	dprintk(("ack was %x\n", (byte >> 8)));
289 
290 	bytecnt = 0;
291 	while (outcnt > 0) {
292 		READUCTLDATA(byte);
293 		txn->outbuf[bytecnt] = (byte >> 8);
294 		dprintk(("set byte to %02x\n", byte));
295 		outcnt--;
296 		bytecnt++;
297 	}
298 }
299 
300 static void uctrl_get_event_status(struct uctrl_driver *driver)
301 {
302 	struct uctrl_txn txn;
303 	u8 outbits[2];
304 
305 	txn.opcode = READ_EVENT_STATUS;
306 	txn.inbits = 0;
307 	txn.outbits = 2;
308 	txn.inbuf = NULL;
309 	txn.outbuf = outbits;
310 
311 	uctrl_do_txn(driver, &txn);
312 
313 	dprintk(("bytes %x %x\n", (outbits[0] & 0xff), (outbits[1] & 0xff)));
314 	driver->status.event_status =
315 		((outbits[0] & 0xff) << 8) | (outbits[1] & 0xff);
316 	dprintk(("ev is %x\n", driver->status.event_status));
317 }
318 
319 static void uctrl_get_external_status(struct uctrl_driver *driver)
320 {
321 	struct uctrl_txn txn;
322 	u8 outbits[2];
323 	int i, v;
324 
325 	txn.opcode = READ_EXTERNAL_STATUS;
326 	txn.inbits = 0;
327 	txn.outbits = 2;
328 	txn.inbuf = NULL;
329 	txn.outbuf = outbits;
330 
331 	uctrl_do_txn(driver, &txn);
332 
333 	dprintk(("bytes %x %x\n", (outbits[0] & 0xff), (outbits[1] & 0xff)));
334 	driver->status.external_status =
335 		((outbits[0] * 256) + (outbits[1]));
336 	dprintk(("ex is %x\n", driver->status.external_status));
337 	v = driver->status.external_status;
338 	for (i = 0; v != 0; i++, v >>= 1) {
339 		if (v & 1) {
340 			dprintk(("%s%s", " ", uctrl_extstatus[i]));
341 		}
342 	}
343 	dprintk(("\n"));
344 
345 }
346 
347 static int uctrl_probe(struct platform_device *op)
348 {
349 	struct uctrl_driver *p;
350 	int err = -ENOMEM;
351 
352 	p = kzalloc(sizeof(*p), GFP_KERNEL);
353 	if (!p) {
354 		printk(KERN_ERR "uctrl: Unable to allocate device struct.\n");
355 		goto out;
356 	}
357 
358 	p->regs = of_ioremap(&op->resource[0], 0,
359 			     resource_size(&op->resource[0]),
360 			     "uctrl");
361 	if (!p->regs) {
362 		printk(KERN_ERR "uctrl: Unable to map registers.\n");
363 		goto out_free;
364 	}
365 
366 	p->irq = op->archdata.irqs[0];
367 	err = request_irq(p->irq, uctrl_interrupt, 0, "uctrl", p);
368 	if (err) {
369 		printk(KERN_ERR "uctrl: Unable to register irq.\n");
370 		goto out_iounmap;
371 	}
372 
373 	err = misc_register(&uctrl_dev);
374 	if (err) {
375 		printk(KERN_ERR "uctrl: Unable to register misc device.\n");
376 		goto out_free_irq;
377 	}
378 
379 	sbus_writel(UCTRL_INTR_RXNE_REQ|UCTRL_INTR_RXNE_MSK, &p->regs->uctrl_intr);
380 	printk(KERN_INFO "%pOF: uctrl regs[0x%p] (irq %d)\n",
381 	       op->dev.of_node, p->regs, p->irq);
382 	uctrl_get_event_status(p);
383 	uctrl_get_external_status(p);
384 
385 	dev_set_drvdata(&op->dev, p);
386 	global_driver = p;
387 
388 out:
389 	return err;
390 
391 out_free_irq:
392 	free_irq(p->irq, p);
393 
394 out_iounmap:
395 	of_iounmap(&op->resource[0], p->regs, resource_size(&op->resource[0]));
396 
397 out_free:
398 	kfree(p);
399 	goto out;
400 }
401 
402 static int uctrl_remove(struct platform_device *op)
403 {
404 	struct uctrl_driver *p = dev_get_drvdata(&op->dev);
405 
406 	if (p) {
407 		misc_deregister(&uctrl_dev);
408 		free_irq(p->irq, p);
409 		of_iounmap(&op->resource[0], p->regs, resource_size(&op->resource[0]));
410 		kfree(p);
411 	}
412 	return 0;
413 }
414 
415 static const struct of_device_id uctrl_match[] = {
416 	{
417 		.name = "uctrl",
418 	},
419 	{},
420 };
421 MODULE_DEVICE_TABLE(of, uctrl_match);
422 
423 static struct platform_driver uctrl_driver = {
424 	.driver = {
425 		.name = "uctrl",
426 		.of_match_table = uctrl_match,
427 	},
428 	.probe		= uctrl_probe,
429 	.remove		= uctrl_remove,
430 };
431 
432 
433 module_platform_driver(uctrl_driver);
434 
435 MODULE_LICENSE("GPL");
436