xref: /openbmc/linux/drivers/staging/nvec/nvec.c (revision f686e9af)
1 // #define DEBUG
2 
3 /* ToDo list (incomplete, unorderd)
4 	- convert mouse, keyboard, and power to platform devices
5 */
6 
7 #include <asm/io.h>
8 #include <asm/irq.h>
9 #include <linux/completion.h>
10 #include <linux/interrupt.h>
11 #include <linux/irq.h>
12 #include <linux/slab.h>
13 #include <linux/gpio.h>
14 #include <linux/serio.h>
15 #include <linux/delay.h>
16 #include <linux/input.h>
17 #include <linux/workqueue.h>
18 #include <linux/clk.h>
19 #include <mach/iomap.h>
20 #include <mach/clk.h>
21 #include <linux/semaphore.h>
22 #include <linux/list.h>
23 #include <linux/notifier.h>
24 #include <linux/platform_device.h>
25 #include <linux/mfd/core.h>
26 #include "nvec.h"
27 
28 static unsigned char EC_DISABLE_EVENT_REPORTING[] =	{'\x04','\x00','\x00'};
29 static unsigned char EC_ENABLE_EVENT_REPORTING[] =	{'\x04','\x00','\x01'};
30 static unsigned char EC_GET_FIRMWARE_VERSION[] =	{'\x07','\x15'};
31 
32 static struct nvec_chip *nvec_power_handle;
33 
34 static struct mfd_cell nvec_devices[] = {
35 	{
36 		.name	= "nvec-kbd",
37 		.id	= 1,
38 	},
39 	{
40 		.name	= "nvec-mouse",
41 		.id	= 1,
42 	},
43 	{
44 		.name	= "nvec-power",
45 		.id	= 1,
46 	},
47 	{
48 		.name	= "nvec-power",
49 		.id	= 2,
50 	},
51 };
52 
53 int nvec_register_notifier(struct nvec_chip *nvec, struct notifier_block *nb,
54 				unsigned int events)
55 {
56 	return atomic_notifier_chain_register(&nvec->notifier_list, nb);
57 }
58 EXPORT_SYMBOL_GPL(nvec_register_notifier);
59 
60 static int nvec_status_notifier(struct notifier_block *nb, unsigned long event_type,
61 				void *data)
62 {
63 	unsigned char *msg = (unsigned char *)data;
64 	int i;
65 
66 	if(event_type != NVEC_CNTL)
67 		return NOTIFY_DONE;
68 
69 	printk("unhandled msg type %ld, payload: ", event_type);
70 	for (i = 0; i < msg[1]; i++)
71 		printk("%0x ", msg[i+2]);
72 	printk("\n");
73 
74 	return NOTIFY_OK;
75 }
76 
77 void nvec_write_async(struct nvec_chip *nvec, unsigned char *data, short size)
78 {
79 	struct nvec_msg *msg = kzalloc(sizeof(struct nvec_msg), GFP_NOWAIT);
80 
81 	msg->data = kzalloc(size, GFP_NOWAIT);
82 	msg->data[0] = size;
83 	memcpy(msg->data + 1, data, size);
84 	msg->size = size + 1;
85 	msg->pos = 0;
86 	INIT_LIST_HEAD(&msg->node);
87 
88 	list_add_tail(&msg->node, &nvec->tx_data);
89 
90 	gpio_set_value(nvec->gpio, 0);
91 }
92 EXPORT_SYMBOL(nvec_write_async);
93 
94 static void nvec_request_master(struct work_struct *work)
95 {
96 	struct nvec_chip *nvec = container_of(work, struct nvec_chip, tx_work);
97 
98 	if(!list_empty(&nvec->tx_data)) {
99 		gpio_set_value(nvec->gpio, 0);
100 	}
101 }
102 
103 static int parse_msg(struct nvec_chip *nvec, struct nvec_msg *msg)
104 {
105 	int i;
106 
107 	if((msg->data[0] & 1<<7) == 0 && msg->data[3]) {
108 		dev_err(nvec->dev, "ec responded %02x %02x %02x %02x\n", msg->data[0],
109 			msg->data[1], msg->data[2], msg->data[3]);
110 		return -EINVAL;
111 	}
112 
113 	if ((msg->data[0] >> 7 ) == 1 && (msg->data[0] & 0x0f) == 5)
114 	{
115 		dev_warn(nvec->dev, "ec system event ");
116 		for (i=0; i < msg->data[1]; i++)
117 			dev_warn(nvec->dev, "%02x ", msg->data[2+i]);
118 		dev_warn(nvec->dev, "\n");
119 	}
120 
121 	atomic_notifier_call_chain(&nvec->notifier_list, msg->data[0] & 0x8f, msg->data);
122 
123 	return 0;
124 }
125 
126 static struct nvec_msg *nvec_write_sync(struct nvec_chip *nvec, unsigned char *data, short size)
127 {
128 	down(&nvec->sync_write_mutex);
129 
130 	nvec->sync_write_pending = (data[1] << 8) + data[0];
131 	nvec_write_async(nvec, data, size);
132 
133 	dev_dbg(nvec->dev, "nvec_sync_write: 0x%04x\n", nvec->sync_write_pending);
134 	wait_for_completion(&nvec->sync_write);
135 	dev_dbg(nvec->dev, "nvec_sync_write: pong!\n");
136 
137 	up(&nvec->sync_write_mutex);
138 
139 	return nvec->last_sync_msg;
140 }
141 
142 /* RX worker */
143 static void nvec_dispatch(struct work_struct *work)
144 {
145 	struct nvec_chip *nvec = container_of(work, struct nvec_chip, rx_work);
146 	struct nvec_msg *msg;
147 
148 	while(!list_empty(&nvec->rx_data))
149 	{
150 		msg = list_first_entry(&nvec->rx_data, struct nvec_msg, node);
151 		list_del_init(&msg->node);
152 
153 		if(nvec->sync_write_pending == (msg->data[2] << 8) + msg->data[0])
154 		{
155 			dev_dbg(nvec->dev, "sync write completed!\n");
156 			nvec->sync_write_pending = 0;
157 			nvec->last_sync_msg = msg;
158 			complete(&nvec->sync_write);
159 		} else {
160 			parse_msg(nvec, msg);
161 			if((!msg) || (!msg->data))
162 				dev_warn(nvec->dev, "attempt access zero pointer\n");
163 			else {
164 				kfree(msg->data);
165 				kfree(msg);
166 			}
167 		}
168 	}
169 }
170 
171 static irqreturn_t nvec_interrupt(int irq, void *dev)
172 {
173 	unsigned long status;
174 	unsigned long received;
175 	unsigned char to_send;
176 	struct nvec_msg *msg;
177 	struct nvec_chip *nvec = (struct nvec_chip *)dev;
178 	void __iomem *base = nvec->base;
179 
180 	status = readl(base + I2C_SL_STATUS);
181 
182 	if(!(status & I2C_SL_IRQ))
183 	{
184 		dev_warn(nvec->dev, "nvec Spurious IRQ\n");
185 		//Yup, handled. ahum.
186 		goto handled;
187 	}
188 	if(status & END_TRANS && !(status & RCVD))
189 	{
190 		//Reenable IRQ only when even has been sent
191 		//printk("Write sequence ended !\n");
192                 //parse_msg(nvec);
193 		nvec->state = NVEC_WAIT;
194 		if(nvec->rx->size > 1)
195 		{
196 			list_add_tail(&nvec->rx->node, &nvec->rx_data);
197 			schedule_work(&nvec->rx_work);
198 		} else {
199 			kfree(nvec->rx->data);
200 			kfree(nvec->rx);
201 		}
202 		return IRQ_HANDLED;
203 	} else if(status & RNW)
204 	{
205 		// Work around for AP20 New Slave Hw Bug. Give 1us extra.
206 		// nvec/smbus/nvec_i2c_transport.c in NV`s crap for reference
207 		if(status & RCVD)
208 			udelay(3);
209 
210 		if(status & RCVD)
211 		{
212 			nvec->state = NVEC_WRITE;
213 			//Master wants something from us. New communication
214 //			dev_dbg(nvec->dev, "New read comm!\n");
215 		} else {
216 			//Master wants something from us from a communication we've already started
217 //			dev_dbg(nvec->dev, "Read comm cont !\n");
218 		}
219 		//if(msg_pos<msg_size) {
220 		if(list_empty(&nvec->tx_data))
221 		{
222 			dev_err(nvec->dev, "nvec empty tx - sending no-op\n");
223 			to_send = 0x8a;
224 			nvec_write_async(nvec, "\x07\x02", 2);
225 //			to_send = 0x01;
226 		} else {
227 			msg = list_first_entry(&nvec->tx_data, struct nvec_msg, node);
228 			if(msg->pos < msg->size) {
229 				to_send = msg->data[msg->pos];
230 				msg->pos++;
231 			} else {
232 				dev_err(nvec->dev, "nvec crap! %d\n", msg->size);
233 				to_send = 0x01;
234 			}
235 
236 			if(msg->pos >= msg->size)
237 			{
238 				list_del_init(&msg->node);
239 				kfree(msg->data);
240 				kfree(msg);
241 				schedule_work(&nvec->tx_work);
242 				nvec->state = NVEC_WAIT;
243 			}
244 		}
245 		writel(to_send, base + I2C_SL_RCVD);
246 
247 		gpio_set_value(nvec->gpio, 1);
248 
249 		dev_dbg(nvec->dev, "nvec sent %x\n", to_send);
250 
251 		goto handled;
252 	} else {
253 		received = readl(base + I2C_SL_RCVD);
254 		//Workaround?
255 		if(status & RCVD) {
256 			writel(0, base + I2C_SL_RCVD);
257 			goto handled;
258 		}
259 
260 		if (nvec->state == NVEC_WAIT)
261 		{
262 			nvec->state = NVEC_READ;
263 			msg = kzalloc(sizeof(struct nvec_msg), GFP_NOWAIT);
264 			msg->data = kzalloc(32, GFP_NOWAIT);
265 			INIT_LIST_HEAD(&msg->node);
266 			nvec->rx = msg;
267 		} else
268 			msg = nvec->rx;
269 
270 		BUG_ON(msg->pos > 32);
271 
272 		msg->data[msg->pos] = received;
273 		msg->pos++;
274 		msg->size = msg->pos;
275 		dev_dbg(nvec->dev, "Got %02lx from Master (pos: %d)!\n", received, msg->pos);
276 	}
277 handled:
278 	return IRQ_HANDLED;
279 }
280 
281 static void tegra_init_i2c_slave(struct nvec_chip *nvec)
282 {
283 	u32 val;
284 
285 	clk_enable(nvec->i2c_clk);
286 
287 	tegra_periph_reset_assert(nvec->i2c_clk);
288 	udelay(2);
289 	tegra_periph_reset_deassert(nvec->i2c_clk);
290 
291 	writel(nvec->i2c_addr>>1, nvec->base + I2C_SL_ADDR1);
292 	writel(0, nvec->base + I2C_SL_ADDR2);
293 
294 	writel(0x1E, nvec->base + I2C_SL_DELAY_COUNT);
295 	val = I2C_CNFG_NEW_MASTER_SFM | I2C_CNFG_PACKET_MODE_EN |
296 		(0x2 << I2C_CNFG_DEBOUNCE_CNT_SHIFT);
297 	writel(val, nvec->base + I2C_CNFG);
298 	writel(I2C_SL_NEWL, nvec->base + I2C_SL_CNFG);
299 
300 	clk_disable(nvec->i2c_clk);
301 }
302 
303 static void nvec_power_off(void)
304 {
305 	nvec_write_async(nvec_power_handle, EC_DISABLE_EVENT_REPORTING, 3);
306 	nvec_write_async(nvec_power_handle, "\x04\x01", 2);
307 }
308 
309 static int __devinit tegra_nvec_probe(struct platform_device *pdev)
310 {
311 	int err, ret;
312 	struct clk *i2c_clk;
313 	struct nvec_platform_data *pdata = pdev->dev.platform_data;
314 	struct nvec_chip *nvec;
315 	struct nvec_msg *msg;
316 	struct resource *res;
317 	struct resource *iomem;
318 	void __iomem *base;
319 
320 	nvec = kzalloc(sizeof(struct nvec_chip), GFP_KERNEL);
321 	if(nvec == NULL) {
322 		dev_err(&pdev->dev, "failed to reserve memory\n");
323 		return -ENOMEM;
324 	}
325 	platform_set_drvdata(pdev, nvec);
326 	nvec->dev = &pdev->dev;
327 	nvec->gpio = pdata->gpio;
328 	nvec->i2c_addr = pdata->i2c_addr;
329 
330 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
331 	if (!res) {
332 		dev_err(&pdev->dev, "no mem resource?\n");
333 		return -ENODEV;
334 	}
335 
336 	iomem = request_mem_region(res->start, resource_size(res), pdev->name);
337 	if (!iomem) {
338 		dev_err(&pdev->dev, "I2C region already claimed\n");
339 		return -EBUSY;
340 	}
341 
342 	base = ioremap(iomem->start, resource_size(iomem));
343 	if (!base) {
344 		dev_err(&pdev->dev, "Can't ioremap I2C region\n");
345 		return -ENOMEM;
346 	}
347 
348 	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
349 	if (!res) {
350 		dev_err(&pdev->dev, "no irq resource?\n");
351 		ret = -ENODEV;
352 		goto err_iounmap;
353 	}
354 
355 	i2c_clk = clk_get_sys("tegra-i2c.2", NULL);
356 	if (IS_ERR(i2c_clk)) {
357 		dev_err(nvec->dev, "failed to get controller clock\n");
358 		goto err_iounmap;
359 	}
360 
361 	clk_enable(i2c_clk);
362 	clk_set_rate(i2c_clk, 8*80000);
363 
364 	nvec->base = base;
365 	nvec->irq = res->start;
366 	nvec->i2c_clk = i2c_clk;
367 
368 	/* Set the gpio to low when we've got something to say */
369 	err = gpio_request(nvec->gpio, "nvec gpio");
370 	if(err < 0)
371 		dev_err(nvec->dev, "couldn't request gpio\n");
372 
373 	ATOMIC_INIT_NOTIFIER_HEAD(&nvec->notifier_list);
374 
375 	init_completion(&nvec->sync_write);
376 	sema_init(&nvec->sync_write_mutex, 1);
377 	INIT_LIST_HEAD(&nvec->tx_data);
378 	INIT_LIST_HEAD(&nvec->rx_data);
379 	INIT_WORK(&nvec->rx_work, nvec_dispatch);
380 	INIT_WORK(&nvec->tx_work, nvec_request_master);
381 
382 	err = request_irq(nvec->irq, nvec_interrupt, 0, "nvec", nvec);
383 	if (err) {
384 		dev_err(nvec->dev, "couldn't request irq\n");
385 		goto failed;
386 	}
387 
388 	tegra_init_i2c_slave(nvec);
389 
390 	gpio_direction_output(nvec->gpio, 1);
391 	gpio_set_value(nvec->gpio, 1);
392 
393 	/* enable event reporting */
394 	nvec_write_async(nvec, EC_ENABLE_EVENT_REPORTING,
395 				sizeof(EC_ENABLE_EVENT_REPORTING));
396 
397 	nvec->nvec_status_notifier.notifier_call = nvec_status_notifier;
398 	nvec_register_notifier(nvec, &nvec->nvec_status_notifier, 0);
399 
400 	nvec_power_handle = nvec;
401 	pm_power_off = nvec_power_off;
402 
403 	/* Get Firmware Version */
404 	msg = nvec_write_sync(nvec, EC_GET_FIRMWARE_VERSION,
405 		sizeof(EC_GET_FIRMWARE_VERSION));
406 
407 	dev_warn(nvec->dev, "ec firmware version %02x.%02x.%02x / %02x\n",
408 			msg->data[4], msg->data[5], msg->data[6], msg->data[7]);
409 
410 	kfree(msg->data);
411 	kfree(msg);
412 
413 	ret = mfd_add_devices(nvec->dev, -1, nvec_devices,
414 			ARRAY_SIZE(nvec_devices), base, 0);
415 	if(ret)
416 		dev_err(nvec->dev, "error adding subdevices\n");
417 
418 	/* unmute speakers? */
419 	nvec_write_async(nvec, "\x0d\x10\x59\x94", 4);
420 
421 	/* enable lid switch event */
422 	nvec_write_async(nvec, "\x01\x01\x01\x00\x00\x02\x00", 7);
423 
424 	/* enable power button event */
425 	nvec_write_async(nvec, "\x01\x01\x01\x00\x00\x80\x00", 7);
426 
427 	return 0;
428 
429 err_iounmap:
430 	iounmap(base);
431 failed:
432 	kfree(nvec);
433 	return -ENOMEM;
434 }
435 
436 static int __devexit tegra_nvec_remove(struct platform_device *pdev)
437 {
438 	struct nvec_chip *nvec = platform_get_drvdata(pdev);
439 
440 	nvec_write_async(nvec, EC_DISABLE_EVENT_REPORTING, 3);
441 	mfd_remove_devices(nvec->dev);
442 	free_irq(nvec->irq, &nvec_interrupt);
443 	iounmap(nvec->base);
444 	gpio_free(nvec->gpio);
445 	kfree(nvec);
446 
447 	return 0;
448 }
449 
450 #ifdef CONFIG_PM
451 
452 static int tegra_nvec_suspend(struct platform_device *pdev, pm_message_t state)
453 {
454 	struct nvec_chip *nvec = platform_get_drvdata(pdev);
455 
456 	dev_dbg(nvec->dev, "suspending\n");
457 	nvec_write_async(nvec, EC_DISABLE_EVENT_REPORTING, 3);
458 	nvec_write_async(nvec, "\x04\x02", 2);
459 
460 	return 0;
461 }
462 
463 static int tegra_nvec_resume(struct platform_device *pdev) {
464 
465 	struct nvec_chip *nvec = platform_get_drvdata(pdev);
466 
467 	dev_dbg(nvec->dev, "resuming\n");
468 	tegra_init_i2c_slave(nvec);
469 	nvec_write_async(nvec, EC_ENABLE_EVENT_REPORTING, 3);
470 
471 	return 0;
472 }
473 
474 #else
475 #define tegra_nvec_suspend NULL
476 #define tegra_nvec_resume NULL
477 #endif
478 
479 static struct platform_driver nvec_device_driver =
480 {
481 	.probe = tegra_nvec_probe,
482 	.remove = __devexit_p(tegra_nvec_remove),
483 	.suspend = tegra_nvec_suspend,
484 	.resume = tegra_nvec_resume,
485 	.driver = {
486 		.name = "nvec",
487 		.owner = THIS_MODULE,
488 	}
489 };
490 
491 static int __init tegra_nvec_init(void)
492 {
493 	return platform_driver_register(&nvec_device_driver);
494 }
495 
496 module_init(tegra_nvec_init);
497 MODULE_ALIAS("platform:nvec");
498