1 /*
2 * dm355evm_msp.c - driver for MSP430 firmware on DM355EVM board
3 *
4 * Copyright (C) 2008 David Brownell
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 */
11
12 #include <linux/init.h>
13 #include <linux/mutex.h>
14 #include <linux/platform_device.h>
15 #include <linux/clk.h>
16 #include <linux/module.h>
17 #include <linux/err.h>
18 #include <linux/gpio.h>
19 #include <linux/leds.h>
20 #include <linux/i2c.h>
21 #include <linux/i2c/dm355evm_msp.h>
22
23
24 /*
25 * The DM355 is a DaVinci chip with video support but no C64+ DSP. Its
26 * EVM board has an MSP430 programmed with firmware for various board
27 * support functions. This driver exposes some of them directly, and
28 * supports other drivers (e.g. RTC, input) for more complex access.
29 *
30 * Because this firmware is entirely board-specific, this file embeds
31 * knowledge that would be passed as platform_data in a generic driver.
32 *
33 * This driver was tested with firmware revision A4.
34 */
35
36 #if defined(CONFIG_INPUT_DM355EVM) || defined(CONFIG_INPUT_DM355EVM_MODULE)
37 #define msp_has_keyboard() true
38 #else
39 #define msp_has_keyboard() false
40 #endif
41
42 #if defined(CONFIG_LEDS_GPIO) || defined(CONFIG_LEDS_GPIO_MODULE)
43 #define msp_has_leds() true
44 #else
45 #define msp_has_leds() false
46 #endif
47
48 #if defined(CONFIG_RTC_DRV_DM355EVM) || defined(CONFIG_RTC_DRV_DM355EVM_MODULE)
49 #define msp_has_rtc() true
50 #else
51 #define msp_has_rtc() false
52 #endif
53
54 #if defined(CONFIG_VIDEO_TVP514X) || defined(CONFIG_VIDEO_TVP514X_MODULE)
55 #define msp_has_tvp() true
56 #else
57 #define msp_has_tvp() false
58 #endif
59
60
61 /*----------------------------------------------------------------------*/
62
63 /* REVISIT for paranoia's sake, retry reads/writes on error */
64
65 static struct i2c_client *msp430;
66
67 /**
68 * dm355evm_msp_write - Writes a register in dm355evm_msp
69 * @value: the value to be written
70 * @reg: register address
71 *
72 * Returns result of operation - 0 is success, else negative errno
73 */
dm355evm_msp_write(u8 value,u8 reg)74 int dm355evm_msp_write(u8 value, u8 reg)
75 {
76 return i2c_smbus_write_byte_data(msp430, reg, value);
77 }
78 EXPORT_SYMBOL(dm355evm_msp_write);
79
80 /**
81 * dm355evm_msp_read - Reads a register from dm355evm_msp
82 * @reg: register address
83 *
84 * Returns result of operation - value, or negative errno
85 */
dm355evm_msp_read(u8 reg)86 int dm355evm_msp_read(u8 reg)
87 {
88 return i2c_smbus_read_byte_data(msp430, reg);
89 }
90 EXPORT_SYMBOL(dm355evm_msp_read);
91
92 /*----------------------------------------------------------------------*/
93
94 /*
95 * Many of the msp430 pins are just used as fixed-direction GPIOs.
96 * We could export a few more of them this way, if we wanted.
97 */
98 #define MSP_GPIO(bit,reg) ((DM355EVM_MSP_ ## reg) << 3 | (bit))
99
100 static const u8 msp_gpios[] = {
101 /* eight leds */
102 MSP_GPIO(0, LED), MSP_GPIO(1, LED),
103 MSP_GPIO(2, LED), MSP_GPIO(3, LED),
104 MSP_GPIO(4, LED), MSP_GPIO(5, LED),
105 MSP_GPIO(6, LED), MSP_GPIO(7, LED),
106 /* SW6 and the NTSC/nPAL jumper */
107 MSP_GPIO(0, SWITCH1), MSP_GPIO(1, SWITCH1),
108 MSP_GPIO(2, SWITCH1), MSP_GPIO(3, SWITCH1),
109 MSP_GPIO(4, SWITCH1),
110 /* switches on MMC/SD sockets */
111 /*
112 * Note: EVMDM355_ECP_VA4.pdf suggests that Bit 2 and 4 should be
113 * checked for card detection. However on the EVM bit 1 and 3 gives
114 * this status, for 0 and 1 instance respectively. The pdf also
115 * suggests that Bit 1 and 3 should be checked for write protection.
116 * However on the EVM bit 2 and 4 gives this status,for 0 and 1
117 * instance respectively.
118 */
119 MSP_GPIO(2, SDMMC), MSP_GPIO(1, SDMMC), /* mmc0 WP, nCD */
120 MSP_GPIO(4, SDMMC), MSP_GPIO(3, SDMMC), /* mmc1 WP, nCD */
121 };
122
123 #define MSP_GPIO_REG(offset) (msp_gpios[(offset)] >> 3)
124 #define MSP_GPIO_MASK(offset) BIT(msp_gpios[(offset)] & 0x07)
125
msp_gpio_in(struct gpio_chip * chip,unsigned offset)126 static int msp_gpio_in(struct gpio_chip *chip, unsigned offset)
127 {
128 switch (MSP_GPIO_REG(offset)) {
129 case DM355EVM_MSP_SWITCH1:
130 case DM355EVM_MSP_SWITCH2:
131 case DM355EVM_MSP_SDMMC:
132 return 0;
133 default:
134 return -EINVAL;
135 }
136 }
137
138 static u8 msp_led_cache;
139
msp_gpio_get(struct gpio_chip * chip,unsigned offset)140 static int msp_gpio_get(struct gpio_chip *chip, unsigned offset)
141 {
142 int reg, status;
143
144 reg = MSP_GPIO_REG(offset);
145 status = dm355evm_msp_read(reg);
146 if (status < 0)
147 return status;
148 if (reg == DM355EVM_MSP_LED)
149 msp_led_cache = status;
150 return status & MSP_GPIO_MASK(offset);
151 }
152
msp_gpio_out(struct gpio_chip * chip,unsigned offset,int value)153 static int msp_gpio_out(struct gpio_chip *chip, unsigned offset, int value)
154 {
155 int mask, bits;
156
157 /* NOTE: there are some other signals that could be
158 * packaged as output GPIOs, but they aren't as useful
159 * as the LEDs ... so for now we don't.
160 */
161 if (MSP_GPIO_REG(offset) != DM355EVM_MSP_LED)
162 return -EINVAL;
163
164 mask = MSP_GPIO_MASK(offset);
165 bits = msp_led_cache;
166
167 bits &= ~mask;
168 if (value)
169 bits |= mask;
170 msp_led_cache = bits;
171
172 return dm355evm_msp_write(bits, DM355EVM_MSP_LED);
173 }
174
msp_gpio_set(struct gpio_chip * chip,unsigned offset,int value)175 static void msp_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
176 {
177 msp_gpio_out(chip, offset, value);
178 }
179
180 static struct gpio_chip dm355evm_msp_gpio = {
181 .label = "dm355evm_msp",
182 .owner = THIS_MODULE,
183 .direction_input = msp_gpio_in,
184 .get = msp_gpio_get,
185 .direction_output = msp_gpio_out,
186 .set = msp_gpio_set,
187 .base = -EINVAL, /* dynamic assignment */
188 .ngpio = ARRAY_SIZE(msp_gpios),
189 .can_sleep = true,
190 };
191
192 /*----------------------------------------------------------------------*/
193
add_child(struct i2c_client * client,const char * name,void * pdata,unsigned pdata_len,bool can_wakeup,int irq)194 static struct device *add_child(struct i2c_client *client, const char *name,
195 void *pdata, unsigned pdata_len,
196 bool can_wakeup, int irq)
197 {
198 struct platform_device *pdev;
199 int status;
200
201 pdev = platform_device_alloc(name, -1);
202 if (!pdev) {
203 dev_dbg(&client->dev, "can't alloc dev\n");
204 status = -ENOMEM;
205 goto err;
206 }
207
208 device_init_wakeup(&pdev->dev, can_wakeup);
209 pdev->dev.parent = &client->dev;
210
211 if (pdata) {
212 status = platform_device_add_data(pdev, pdata, pdata_len);
213 if (status < 0) {
214 dev_dbg(&pdev->dev, "can't add platform_data\n");
215 goto err;
216 }
217 }
218
219 if (irq) {
220 struct resource r = {
221 .start = irq,
222 .flags = IORESOURCE_IRQ,
223 };
224
225 status = platform_device_add_resources(pdev, &r, 1);
226 if (status < 0) {
227 dev_dbg(&pdev->dev, "can't add irq\n");
228 goto err;
229 }
230 }
231
232 status = platform_device_add(pdev);
233
234 err:
235 if (status < 0) {
236 platform_device_put(pdev);
237 dev_err(&client->dev, "can't add %s dev\n", name);
238 return ERR_PTR(status);
239 }
240 return &pdev->dev;
241 }
242
add_children(struct i2c_client * client)243 static int add_children(struct i2c_client *client)
244 {
245 static const struct {
246 int offset;
247 char *label;
248 } config_inputs[] = {
249 /* 8 == right after the LEDs */
250 { 8 + 0, "sw6_1", },
251 { 8 + 1, "sw6_2", },
252 { 8 + 2, "sw6_3", },
253 { 8 + 3, "sw6_4", },
254 { 8 + 4, "NTSC/nPAL", },
255 };
256
257 struct device *child;
258 int status;
259 int i;
260
261 /* GPIO-ish stuff */
262 dm355evm_msp_gpio.dev = &client->dev;
263 status = gpiochip_add(&dm355evm_msp_gpio);
264 if (status < 0)
265 return status;
266
267 /* LED output */
268 if (msp_has_leds()) {
269 #define GPIO_LED(l) .name = l, .active_low = true
270 static struct gpio_led evm_leds[] = {
271 { GPIO_LED("dm355evm::ds14"),
272 .default_trigger = "heartbeat", },
273 { GPIO_LED("dm355evm::ds15"),
274 .default_trigger = "mmc0", },
275 { GPIO_LED("dm355evm::ds16"),
276 /* could also be a CE-ATA drive */
277 .default_trigger = "mmc1", },
278 { GPIO_LED("dm355evm::ds17"),
279 .default_trigger = "nand-disk", },
280 { GPIO_LED("dm355evm::ds18"), },
281 { GPIO_LED("dm355evm::ds19"), },
282 { GPIO_LED("dm355evm::ds20"), },
283 { GPIO_LED("dm355evm::ds21"), },
284 };
285 #undef GPIO_LED
286
287 struct gpio_led_platform_data evm_led_data = {
288 .num_leds = ARRAY_SIZE(evm_leds),
289 .leds = evm_leds,
290 };
291
292 for (i = 0; i < ARRAY_SIZE(evm_leds); i++)
293 evm_leds[i].gpio = i + dm355evm_msp_gpio.base;
294
295 /* NOTE: these are the only fully programmable LEDs
296 * on the board, since GPIO-61/ds22 (and many signals
297 * going to DC7) must be used for AEMIF address lines
298 * unless the top 1 GB of NAND is unused...
299 */
300 child = add_child(client, "leds-gpio",
301 &evm_led_data, sizeof(evm_led_data),
302 false, 0);
303 if (IS_ERR(child))
304 return PTR_ERR(child);
305 }
306
307 /* configuration inputs */
308 for (i = 0; i < ARRAY_SIZE(config_inputs); i++) {
309 int gpio = dm355evm_msp_gpio.base + config_inputs[i].offset;
310
311 gpio_request_one(gpio, GPIOF_IN, config_inputs[i].label);
312
313 /* make it easy for userspace to see these */
314 gpio_export(gpio, false);
315 }
316
317 /* MMC/SD inputs -- right after the last config input */
318 if (client->dev.platform_data) {
319 void (*mmcsd_setup)(unsigned) = client->dev.platform_data;
320
321 mmcsd_setup(dm355evm_msp_gpio.base + 8 + 5);
322 }
323
324 /* RTC is a 32 bit counter, no alarm */
325 if (msp_has_rtc()) {
326 child = add_child(client, "rtc-dm355evm",
327 NULL, 0, false, 0);
328 if (IS_ERR(child))
329 return PTR_ERR(child);
330 }
331
332 /* input from buttons and IR remote (uses the IRQ) */
333 if (msp_has_keyboard()) {
334 child = add_child(client, "dm355evm_keys",
335 NULL, 0, true, client->irq);
336 if (IS_ERR(child))
337 return PTR_ERR(child);
338 }
339
340 return 0;
341 }
342
343 /*----------------------------------------------------------------------*/
344
dm355evm_command(unsigned command)345 static void dm355evm_command(unsigned command)
346 {
347 int status;
348
349 status = dm355evm_msp_write(command, DM355EVM_MSP_COMMAND);
350 if (status < 0)
351 dev_err(&msp430->dev, "command %d failure %d\n",
352 command, status);
353 }
354
dm355evm_power_off(void)355 static void dm355evm_power_off(void)
356 {
357 dm355evm_command(MSP_COMMAND_POWEROFF);
358 }
359
dm355evm_msp_remove(struct i2c_client * client)360 static int dm355evm_msp_remove(struct i2c_client *client)
361 {
362 pm_power_off = NULL;
363 msp430 = NULL;
364 return 0;
365 }
366
367 static int
dm355evm_msp_probe(struct i2c_client * client,const struct i2c_device_id * id)368 dm355evm_msp_probe(struct i2c_client *client, const struct i2c_device_id *id)
369 {
370 int status;
371 const char *video = msp_has_tvp() ? "TVP5146" : "imager";
372
373 if (msp430)
374 return -EBUSY;
375 msp430 = client;
376
377 /* display revision status; doubles as sanity check */
378 status = dm355evm_msp_read(DM355EVM_MSP_FIRMREV);
379 if (status < 0)
380 goto fail;
381 dev_info(&client->dev, "firmware v.%02X, %s as video-in\n",
382 status, video);
383
384 /* mux video input: either tvp5146 or some external imager */
385 status = dm355evm_msp_write(msp_has_tvp() ? 0 : MSP_VIDEO_IMAGER,
386 DM355EVM_MSP_VIDEO_IN);
387 if (status < 0)
388 dev_warn(&client->dev, "error %d muxing %s as video-in\n",
389 status, video);
390
391 /* init LED cache, and turn off the LEDs */
392 msp_led_cache = 0xff;
393 dm355evm_msp_write(msp_led_cache, DM355EVM_MSP_LED);
394
395 /* export capabilities we support */
396 status = add_children(client);
397 if (status < 0)
398 goto fail;
399
400 /* PM hookup */
401 pm_power_off = dm355evm_power_off;
402
403 return 0;
404
405 fail:
406 /* FIXME remove children ... */
407 dm355evm_msp_remove(client);
408 return status;
409 }
410
411 static const struct i2c_device_id dm355evm_msp_ids[] = {
412 { "dm355evm_msp", 0 },
413 { /* end of list */ },
414 };
415 MODULE_DEVICE_TABLE(i2c, dm355evm_msp_ids);
416
417 static struct i2c_driver dm355evm_msp_driver = {
418 .driver.name = "dm355evm_msp",
419 .id_table = dm355evm_msp_ids,
420 .probe = dm355evm_msp_probe,
421 .remove = dm355evm_msp_remove,
422 };
423
dm355evm_msp_init(void)424 static int __init dm355evm_msp_init(void)
425 {
426 return i2c_add_driver(&dm355evm_msp_driver);
427 }
428 subsys_initcall(dm355evm_msp_init);
429
dm355evm_msp_exit(void)430 static void __exit dm355evm_msp_exit(void)
431 {
432 i2c_del_driver(&dm355evm_msp_driver);
433 }
434 module_exit(dm355evm_msp_exit);
435
436 MODULE_DESCRIPTION("Interface to MSP430 firmware on DM355EVM");
437 MODULE_LICENSE("GPL");
438