aboutsummaryrefslogtreecommitdiff
path: root/drivers/mfd/dm355evm_msp.c
blob: 7a55c0071fa8e9840b47420277673120547df191 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
/*
 * dm355evm_msp.c - driver for MSP430 firmware on DM355EVM board
 *
 * Copyright (C) 2008 David Brownell
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/leds.h>
#include <linux/i2c.h>
#include <linux/i2c/dm355evm_msp.h>


/*
 * The DM355 is a DaVinci chip with video support but no C64+ DSP.  Its
 * EVM board has an MSP430 programmed with firmware for various board
 * support functions.  This driver exposes some of them directly, and
 * supports other drivers (e.g. RTC, input) for more complex access.
 *
 * Because this firmware is entirely board-specific, this file embeds
 * knowledge that would be passed as platform_data in a generic driver.
 *
 * This driver was tested with firmware revision A4.
 */

#if defined(CONFIG_INPUT_DM355EVM) || defined(CONFIG_INPUT_DM355EVM_MODULE)
#define msp_has_keyboard()	true
#else
#define msp_has_keyboard()	false
#endif

#if defined(CONFIG_LEDS_GPIO) || defined(CONFIG_LEDS_GPIO_MODULE)
#define msp_has_leds()		true
#else
#define msp_has_leds()		false
#endif

#if defined(CONFIG_RTC_DRV_DM355EVM) || defined(CONFIG_RTC_DRV_DM355EVM_MODULE)
#define msp_has_rtc()		true
#else
#define msp_has_rtc()		false
#endif

#if defined(CONFIG_VIDEO_TVP514X) || defined(CONFIG_VIDEO_TVP514X_MODULE)
#define msp_has_tvp()		true
#else
#define msp_has_tvp()		false
#endif


/*----------------------------------------------------------------------*/

/* REVISIT for paranoia's sake, retry reads/writes on error */

static struct i2c_client *msp430;

/**
 * dm355evm_msp_write - Writes a register in dm355evm_msp
 * @value: the value to be written
 * @reg: register address
 *
 * Returns result of operation - 0 is success, else negative errno
 */
int dm355evm_msp_write(u8 value, u8 reg)
{
	return i2c_smbus_write_byte_data(msp430, reg, value);
}
EXPORT_SYMBOL(dm355evm_msp_write);

/**
 * dm355evm_msp_read - Reads a register from dm355evm_msp
 * @reg: register address
 *
 * Returns result of operation - value, or negative errno
 */
int dm355evm_msp_read(u8 reg)
{
	return i2c_smbus_read_byte_data(msp430, reg);
}
EXPORT_SYMBOL(dm355evm_msp_read);

/*----------------------------------------------------------------------*/

/*
 * Many of the msp430 pins are just used as fixed-direction GPIOs.
 * We could export a few more of them this way, if we wanted.
 */
#define MSP_GPIO(bit,reg)	((DM355EVM_MSP_ ## reg) << 3 | (bit))

static const u8 msp_gpios[] = {
	/* eight leds */
	MSP_GPIO(0, LED), MSP_GPIO(1, LED),
	MSP_GPIO(2, LED), MSP_GPIO(3, LED),
	MSP_GPIO(4, LED), MSP_GPIO(5, LED),
	MSP_GPIO(6, LED), MSP_GPIO(7, LED),
	/* SW6 and the NTSC/nPAL jumper */
	MSP_GPIO(0, SWITCH1), MSP_GPIO(1, SWITCH1),
	MSP_GPIO(2, SWITCH1), MSP_GPIO(3, SWITCH1),
	MSP_GPIO(4, SWITCH1),
	/* switches on MMC/SD sockets */
	/*
	 * Note: EVMDM355_ECP_VA4.pdf suggests that Bit 2 and 4 should be
	 * checked for card detection. However on the EVM bit 1 and 3 gives
	 * this status, for 0 and 1 instance respectively. The pdf also
	 * suggests that Bit 1 and 3 should be checked for write protection.
	 * However on the EVM bit 2 and 4 gives this status,for 0 and 1
	 * instance respectively.
	 */
	MSP_GPIO(2, SDMMC), MSP_GPIO(1, SDMMC),	/* mmc0 WP, nCD */
	MSP_GPIO(4, SDMMC), MSP_GPIO(3, SDMMC),	/* mmc1 WP, nCD */
};

#define MSP_GPIO_REG(offset)	(msp_gpios[(offset)] >> 3)
#define MSP_GPIO_MASK(offset)	BIT(msp_gpios[(offset)] & 0x07)

static int msp_gpio_in(struct gpio_chip *chip, unsigned offset)
{
	switch (MSP_GPIO_REG(offset)) {
	case DM355EVM_MSP_SWITCH1:
	case DM355EVM_MSP_SWITCH2:
	case DM355EVM_MSP_SDMMC:
		return 0;
	default:
		return -EINVAL;
	}
}

static u8 msp_led_cache;

static int msp_gpio_get(struct gpio_chip *chip, unsigned offset)
{
	int reg, status;

	reg = MSP_GPIO_REG(offset);
	status = dm355evm_msp_read(reg);
	if (status < 0)
		return status;
	if (reg == DM355EVM_MSP_LED)
		msp_led_cache = status;
	return status & MSP_GPIO_MASK(offset);
}

static int msp_gpio_out(struct gpio_chip *chip, unsigned offset, int value)
{
	int mask, bits;

	/* NOTE:  there are some other signals that could be
	 * packaged as output GPIOs, but they aren't as useful
	 * as the LEDs ... so for now we don't.
	 */
	if (MSP_GPIO_REG(offset) != DM355EVM_MSP_LED)
		return -EINVAL;

	mask = MSP_GPIO_MASK(offset);
	bits = msp_led_cache;

	bits &= ~mask;
	if (value)
		bits |= mask;
	msp_led_cache = bits;

	return dm355evm_msp_write(bits, DM355EVM_MSP_LED);
}

static void msp_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
	msp_gpio_out(chip, offset, value);
}

static struct gpio_chip dm355evm_msp_gpio = {
	.label			= "dm355evm_msp",
	.owner			= THIS_MODULE,
	.direction_input	= msp_gpio_in,
	.get			= msp_gpio_get,
	.direction_output	= msp_gpio_out,
	.set			= msp_gpio_set,
	.base			= -EINVAL,		/* dynamic assignment */
	.ngpio			= ARRAY_SIZE(msp_gpios),
	.can_sleep		= true,
};

/*----------------------------------------------------------------------*/

static struct device *add_child(struct i2c_client *client, const char *name,
		void *pdata, unsigned pdata_len,
		bool can_wakeup, int irq)
{
	struct platform_device	*pdev;
	int			status;

	pdev = platform_device_alloc(name, -1);
	if (!pdev) {
		dev_dbg(&client->dev, "can't alloc dev\n");
		status = -ENOMEM;
		goto err;
	}

	device_init_wakeup(&pdev->dev, can_wakeup);
	pdev->dev.parent = &client->dev;

	if (pdata) {
		status = platform_device_add_data(pdev, pdata, pdata_len);
		if (status < 0) {
			dev_dbg(&pdev->dev, "can't add platform_data\n");
			goto err;
		}
	}

	if (irq) {
		struct resource r = {
			.start = irq,
			.flags = IORESOURCE_IRQ,
		};

		status = platform_device_add_resources(pdev, &r, 1);
		if (status < 0) {
			dev_dbg(&pdev->dev, "can't add irq\n");
			goto err;
		}
	}

	status = platform_device_add(pdev);

err:
	if (status < 0) {
		platform_device_put(pdev);
		dev_err(&client->dev, "can't add %s dev\n", name);
		return ERR_PTR(status);
	}
	return &pdev->dev;
}

static int add_children(struct i2c_client *client)
{
	static const struct {
		int offset;
		char *label;
	} config_inputs[] = {
		/* 8 == right after the LEDs */
		{ 8 + 0, "sw6_1", },
		{ 8 + 1, "sw6_2", },
		{ 8 + 2, "sw6_3", },
		{ 8 + 3, "sw6_4", },
		{ 8 + 4, "NTSC/nPAL", },
	};

	struct device	*child;
	int		status;
	int		i;

	/* GPIO-ish stuff */
	dm355evm_msp_gpio.dev = &client->dev;
	status = gpiochip_add(&dm355evm_msp_gpio);
	if (status < 0)
		return status;

	/* LED output */
	if (msp_has_leds()) {
#define GPIO_LED(l)	.name = l, .active_low = true
		static struct gpio_led evm_leds[] = {
			{ GPIO_LED("dm355evm::ds14"),
				.default_trigger = "heartbeat", },
			{ GPIO_LED("dm355evm::ds15"),
				.default_trigger = "mmc0", },
			{ GPIO_LED("dm355evm::ds16"),
				/* could also be a CE-ATA drive */
				.default_trigger = "mmc1", },
			{ GPIO_LED("dm355evm::ds17"),
				.default_trigger = "nand-disk", },
			{ GPIO_LED("dm355evm::ds18"), },
			{ GPIO_LED("dm355evm::ds19"), },
			{ GPIO_LED("dm355evm::ds20"), },
			{ GPIO_LED("dm355evm::ds21"), },
		};
#undef GPIO_LED

		struct gpio_led_platform_data evm_led_data = {
			.num_leds	= ARRAY_SIZE(evm_leds),
			.leds		= evm_leds,
		};

		for (i = 0; i < ARRAY_SIZE(evm_leds); i++)
			evm_leds[i].gpio = i + dm355evm_msp_gpio.base;

		/* NOTE:  these are the only fully programmable LEDs
		 * on the board, since GPIO-61/ds22 (and many signals
		 * going to DC7) must be used for AEMIF address lines
		 * unless the top 1 GB of NAND is unused...
		 */
		child = add_child(client, "leds-gpio",
				&evm_led_data, sizeof(evm_led_data),
				false, 0);
		if (IS_ERR(child))
			return PTR_ERR(child);
	}

	/* configuration inputs */
	for (i = 0; i < ARRAY_SIZE(config_inputs); i++) {
		int gpio = dm355evm_msp_gpio.base + config_inputs[i].offset;

		gpio_request_one(gpio, GPIOF_IN, config_inputs[i].label);

		/* make it easy for userspace to see these */
		gpio_export(gpio, false);
	}

	/* MMC/SD inputs -- right after the last config input */
	if (dev_get_platdata(&client->dev)) {
		void (*mmcsd_setup)(unsigned) = dev_get_platdata(&client->dev);

		mmcsd_setup(dm355evm_msp_gpio.base + 8 + 5);
	}

	/* RTC is a 32 bit counter, no alarm */
	if (msp_has_rtc()) {
		child = add_child(client, "rtc-dm355evm",
				NULL, 0, false, 0);
		if (IS_ERR(child))
			return PTR_ERR(child);
	}

	/* input from buttons and IR remote (uses the IRQ) */
	if (msp_has_keyboard()) {
		child = add_child(client, "dm355evm_keys",
				NULL, 0, true, client->irq);
		if (IS_ERR(child))
			return PTR_ERR(child);
	}

	return 0;
}

/*----------------------------------------------------------------------*/

static void dm355evm_command(unsigned command)
{
	int status;

	status = dm355evm_msp_write(command, DM355EVM_MSP_COMMAND);
	if (status < 0)
		dev_err(&msp430->dev, "command %d failure %d\n",
				command, status);
}

static void dm355evm_power_off(void)
{
	dm355evm_command(MSP_COMMAND_POWEROFF);
}

static int dm355evm_msp_remove(struct i2c_client *client)
{
	pm_power_off = NULL;
	msp430 = NULL;
	return 0;
}

static int
dm355evm_msp_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
	int		status;
	const char	*video = msp_has_tvp() ? "TVP5146" : "imager";

	if (msp430)
		return -EBUSY;
	msp430 = client;

	/* display revision status; doubles as sanity check */
	status = dm355evm_msp_read(DM355EVM_MSP_FIRMREV);
	if (status < 0)
		goto fail;
	dev_info(&client->dev, "firmware v.%02X, %s as video-in\n",
			status, video);

	/* mux video input:  either tvp5146 or some external imager */
	status = dm355evm_msp_write(msp_has_tvp() ? 0 : MSP_VIDEO_IMAGER,
			DM355EVM_MSP_VIDEO_IN);
	if (status < 0)
		dev_warn(&client->dev, "error %d muxing %s as video-in\n",
			status, video);

	/* init LED cache, and turn off the LEDs */
	msp_led_cache = 0xff;
	dm355evm_msp_write(msp_led_cache, DM355EVM_MSP_LED);

	/* export capabilities we support */
	status = add_children(client);
	if (status < 0)
		goto fail;

	/* PM hookup */
	pm_power_off = dm355evm_power_off;

	return 0;

fail:
	/* FIXME remove children ... */
	dm355evm_msp_remove(client);
	return status;
}

static const struct i2c_device_id dm355evm_msp_ids[] = {
	{ "dm355evm_msp", 0 },
	{ /* end of list */ },
};
MODULE_DEVICE_TABLE(i2c, dm355evm_msp_ids);

static struct i2c_driver dm355evm_msp_driver = {
	.driver.name	= "dm355evm_msp",
	.id_table	= dm355evm_msp_ids,
	.probe		= dm355evm_msp_probe,
	.remove		= dm355evm_msp_remove,
};

static int __init dm355evm_msp_init(void)
{
	return i2c_add_driver(&dm355evm_msp_driver);
}
subsys_initcall(dm355evm_msp_init);

static void __exit dm355evm_msp_exit(void)
{
	i2c_del_driver(&dm355evm_msp_driver);
}
module_exit(dm355evm_msp_exit);

MODULE_DESCRIPTION("Interface to MSP430 firmware on DM355EVM");
MODULE_LICENSE("GPL");