1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * dm355evm_msp.c - driver for MSP430 firmware on DM355EVM board
4 *
5 * Copyright (C) 2008 David Brownell
6 */
7
8 #include <linux/init.h>
9 #include <linux/mutex.h>
10 #include <linux/platform_device.h>
11 #include <linux/clk.h>
12 #include <linux/module.h>
13 #include <linux/err.h>
14 #include <linux/gpio.h>
15 #include <linux/gpio/machine.h>
16 #include <linux/leds.h>
17 #include <linux/i2c.h>
18 #include <linux/mfd/dm355evm_msp.h>
19
20
21 /*
22 * The DM355 is a DaVinci chip with video support but no C64+ DSP. Its
23 * EVM board has an MSP430 programmed with firmware for various board
24 * support functions. This driver exposes some of them directly, and
25 * supports other drivers (e.g. RTC, input) for more complex access.
26 *
27 * Because this firmware is entirely board-specific, this file embeds
28 * knowledge that would be passed as platform_data in a generic driver.
29 *
30 * This driver was tested with firmware revision A4.
31 */
32
33 #if IS_ENABLED(CONFIG_INPUT_DM355EVM)
34 #define msp_has_keyboard() true
35 #else
36 #define msp_has_keyboard() false
37 #endif
38
39 #if IS_ENABLED(CONFIG_LEDS_GPIO)
40 #define msp_has_leds() true
41 #else
42 #define msp_has_leds() false
43 #endif
44
45 #if IS_ENABLED(CONFIG_RTC_DRV_DM355EVM)
46 #define msp_has_rtc() true
47 #else
48 #define msp_has_rtc() false
49 #endif
50
51 #if IS_ENABLED(CONFIG_VIDEO_TVP514X)
52 #define msp_has_tvp() true
53 #else
54 #define msp_has_tvp() false
55 #endif
56
57
58 /*----------------------------------------------------------------------*/
59
60 /* REVISIT for paranoia's sake, retry reads/writes on error */
61
62 static struct i2c_client *msp430;
63
64 /**
65 * dm355evm_msp_write - Writes a register in dm355evm_msp
66 * @value: the value to be written
67 * @reg: register address
68 *
69 * Returns result of operation - 0 is success, else negative errno
70 */
dm355evm_msp_write(u8 value,u8 reg)71 int dm355evm_msp_write(u8 value, u8 reg)
72 {
73 return i2c_smbus_write_byte_data(msp430, reg, value);
74 }
75 EXPORT_SYMBOL(dm355evm_msp_write);
76
77 /**
78 * dm355evm_msp_read - Reads a register from dm355evm_msp
79 * @reg: register address
80 *
81 * Returns result of operation - value, or negative errno
82 */
dm355evm_msp_read(u8 reg)83 int dm355evm_msp_read(u8 reg)
84 {
85 return i2c_smbus_read_byte_data(msp430, reg);
86 }
87 EXPORT_SYMBOL(dm355evm_msp_read);
88
89 /*----------------------------------------------------------------------*/
90
91 /*
92 * Many of the msp430 pins are just used as fixed-direction GPIOs.
93 * We could export a few more of them this way, if we wanted.
94 */
95 #define MSP_GPIO(bit, reg) ((DM355EVM_MSP_ ## reg) << 3 | (bit))
96
97 static const u8 msp_gpios[] = {
98 /* eight leds */
99 MSP_GPIO(0, LED), MSP_GPIO(1, LED),
100 MSP_GPIO(2, LED), MSP_GPIO(3, LED),
101 MSP_GPIO(4, LED), MSP_GPIO(5, LED),
102 MSP_GPIO(6, LED), MSP_GPIO(7, LED),
103 /* SW6 and the NTSC/nPAL jumper */
104 MSP_GPIO(0, SWITCH1), MSP_GPIO(1, SWITCH1),
105 MSP_GPIO(2, SWITCH1), MSP_GPIO(3, SWITCH1),
106 MSP_GPIO(4, SWITCH1),
107 /* switches on MMC/SD sockets */
108 /*
109 * Note: EVMDM355_ECP_VA4.pdf suggests that Bit 2 and 4 should be
110 * checked for card detection. However on the EVM bit 1 and 3 gives
111 * this status, for 0 and 1 instance respectively. The pdf also
112 * suggests that Bit 1 and 3 should be checked for write protection.
113 * However on the EVM bit 2 and 4 gives this status,for 0 and 1
114 * instance respectively.
115 */
116 MSP_GPIO(2, SDMMC), MSP_GPIO(1, SDMMC), /* mmc0 WP, nCD */
117 MSP_GPIO(4, SDMMC), MSP_GPIO(3, SDMMC), /* mmc1 WP, nCD */
118 };
119
120 static struct gpio_led evm_leds[] = {
121 { .name = "dm355evm::ds14",
122 .default_trigger = "heartbeat", },
123 { .name = "dm355evm::ds15",
124 .default_trigger = "mmc0", },
125 { .name = "dm355evm::ds16",
126 /* could also be a CE-ATA drive */
127 .default_trigger = "mmc1", },
128 { .name = "dm355evm::ds17",
129 .default_trigger = "nand-disk", },
130 { .name = "dm355evm::ds18", },
131 { .name = "dm355evm::ds19", },
132 { .name = "dm355evm::ds20", },
133 { .name = "dm355evm::ds21", },
134 };
135
136 static struct gpio_led_platform_data evm_led_data = {
137 .num_leds = ARRAY_SIZE(evm_leds),
138 .leds = evm_leds,
139 };
140
141 static struct gpiod_lookup_table evm_leds_gpio_table = {
142 .dev_id = "leds-gpio",
143 .table = {
144 /*
145 * These GPIOs are on the dm355evm_msp
146 * GPIO chip at index 0..7
147 */
148 GPIO_LOOKUP_IDX("dm355evm_msp", 0, NULL,
149 0, GPIO_ACTIVE_LOW),
150 GPIO_LOOKUP_IDX("dm355evm_msp", 1, NULL,
151 1, GPIO_ACTIVE_LOW),
152 GPIO_LOOKUP_IDX("dm355evm_msp", 2, NULL,
153 2, GPIO_ACTIVE_LOW),
154 GPIO_LOOKUP_IDX("dm355evm_msp", 3, NULL,
155 3, GPIO_ACTIVE_LOW),
156 GPIO_LOOKUP_IDX("dm355evm_msp", 4, NULL,
157 4, GPIO_ACTIVE_LOW),
158 GPIO_LOOKUP_IDX("dm355evm_msp", 5, NULL,
159 5, GPIO_ACTIVE_LOW),
160 GPIO_LOOKUP_IDX("dm355evm_msp", 6, NULL,
161 6, GPIO_ACTIVE_LOW),
162 GPIO_LOOKUP_IDX("dm355evm_msp", 7, NULL,
163 7, GPIO_ACTIVE_LOW),
164 { },
165 },
166 };
167
168 #define MSP_GPIO_REG(offset) (msp_gpios[(offset)] >> 3)
169 #define MSP_GPIO_MASK(offset) BIT(msp_gpios[(offset)] & 0x07)
170
msp_gpio_in(struct gpio_chip * chip,unsigned offset)171 static int msp_gpio_in(struct gpio_chip *chip, unsigned offset)
172 {
173 switch (MSP_GPIO_REG(offset)) {
174 case DM355EVM_MSP_SWITCH1:
175 case DM355EVM_MSP_SWITCH2:
176 case DM355EVM_MSP_SDMMC:
177 return 0;
178 default:
179 return -EINVAL;
180 }
181 }
182
183 static u8 msp_led_cache;
184
msp_gpio_get(struct gpio_chip * chip,unsigned offset)185 static int msp_gpio_get(struct gpio_chip *chip, unsigned offset)
186 {
187 int reg, status;
188
189 reg = MSP_GPIO_REG(offset);
190 status = dm355evm_msp_read(reg);
191 if (status < 0)
192 return status;
193 if (reg == DM355EVM_MSP_LED)
194 msp_led_cache = status;
195 return !!(status & MSP_GPIO_MASK(offset));
196 }
197
msp_gpio_out(struct gpio_chip * chip,unsigned offset,int value)198 static int msp_gpio_out(struct gpio_chip *chip, unsigned offset, int value)
199 {
200 int mask, bits;
201
202 /* NOTE: there are some other signals that could be
203 * packaged as output GPIOs, but they aren't as useful
204 * as the LEDs ... so for now we don't.
205 */
206 if (MSP_GPIO_REG(offset) != DM355EVM_MSP_LED)
207 return -EINVAL;
208
209 mask = MSP_GPIO_MASK(offset);
210 bits = msp_led_cache;
211
212 bits &= ~mask;
213 if (value)
214 bits |= mask;
215 msp_led_cache = bits;
216
217 return dm355evm_msp_write(bits, DM355EVM_MSP_LED);
218 }
219
msp_gpio_set(struct gpio_chip * chip,unsigned offset,int value)220 static void msp_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
221 {
222 msp_gpio_out(chip, offset, value);
223 }
224
225 static struct gpio_chip dm355evm_msp_gpio = {
226 .label = "dm355evm_msp",
227 .owner = THIS_MODULE,
228 .direction_input = msp_gpio_in,
229 .get = msp_gpio_get,
230 .direction_output = msp_gpio_out,
231 .set = msp_gpio_set,
232 .base = -EINVAL, /* dynamic assignment */
233 .ngpio = ARRAY_SIZE(msp_gpios),
234 .can_sleep = true,
235 };
236
237 /*----------------------------------------------------------------------*/
238
add_child(struct i2c_client * client,const char * name,void * pdata,unsigned pdata_len,bool can_wakeup,int irq)239 static struct device *add_child(struct i2c_client *client, const char *name,
240 void *pdata, unsigned pdata_len,
241 bool can_wakeup, int irq)
242 {
243 struct platform_device *pdev;
244 int status;
245
246 pdev = platform_device_alloc(name, -1);
247 if (!pdev)
248 return ERR_PTR(-ENOMEM);
249
250 device_init_wakeup(&pdev->dev, can_wakeup);
251 pdev->dev.parent = &client->dev;
252
253 if (pdata) {
254 status = platform_device_add_data(pdev, pdata, pdata_len);
255 if (status < 0) {
256 dev_dbg(&pdev->dev, "can't add platform_data\n");
257 goto put_device;
258 }
259 }
260
261 if (irq) {
262 struct resource r = {
263 .start = irq,
264 .flags = IORESOURCE_IRQ,
265 };
266
267 status = platform_device_add_resources(pdev, &r, 1);
268 if (status < 0) {
269 dev_dbg(&pdev->dev, "can't add irq\n");
270 goto put_device;
271 }
272 }
273
274 status = platform_device_add(pdev);
275 if (status)
276 goto put_device;
277
278 return &pdev->dev;
279
280 put_device:
281 platform_device_put(pdev);
282 dev_err(&client->dev, "failed to add device %s\n", name);
283 return ERR_PTR(status);
284 }
285
add_children(struct i2c_client * client)286 static int add_children(struct i2c_client *client)
287 {
288 static const struct {
289 int offset;
290 char *label;
291 } config_inputs[] = {
292 /* 8 == right after the LEDs */
293 { 8 + 0, "sw6_1", },
294 { 8 + 1, "sw6_2", },
295 { 8 + 2, "sw6_3", },
296 { 8 + 3, "sw6_4", },
297 { 8 + 4, "NTSC/nPAL", },
298 };
299
300 struct device *child;
301 int status;
302 int i;
303
304 /* GPIO-ish stuff */
305 dm355evm_msp_gpio.parent = &client->dev;
306 status = gpiochip_add_data(&dm355evm_msp_gpio, NULL);
307 if (status < 0)
308 return status;
309
310 /* LED output */
311 if (msp_has_leds()) {
312 gpiod_add_lookup_table(&evm_leds_gpio_table);
313 /* NOTE: these are the only fully programmable LEDs
314 * on the board, since GPIO-61/ds22 (and many signals
315 * going to DC7) must be used for AEMIF address lines
316 * unless the top 1 GB of NAND is unused...
317 */
318 child = add_child(client, "leds-gpio",
319 &evm_led_data, sizeof(evm_led_data),
320 false, 0);
321 if (IS_ERR(child))
322 return PTR_ERR(child);
323 }
324
325 /* configuration inputs */
326 for (i = 0; i < ARRAY_SIZE(config_inputs); i++) {
327 int gpio = dm355evm_msp_gpio.base + config_inputs[i].offset;
328
329 gpio_request_one(gpio, GPIOF_IN, config_inputs[i].label);
330
331 /* make it easy for userspace to see these */
332 gpio_export(gpio, false);
333 }
334
335 /* MMC/SD inputs -- right after the last config input */
336 if (dev_get_platdata(&client->dev)) {
337 void (*mmcsd_setup)(unsigned) = dev_get_platdata(&client->dev);
338
339 mmcsd_setup(dm355evm_msp_gpio.base + 8 + 5);
340 }
341
342 /* RTC is a 32 bit counter, no alarm */
343 if (msp_has_rtc()) {
344 child = add_child(client, "rtc-dm355evm",
345 NULL, 0, false, 0);
346 if (IS_ERR(child))
347 return PTR_ERR(child);
348 }
349
350 /* input from buttons and IR remote (uses the IRQ) */
351 if (msp_has_keyboard()) {
352 child = add_child(client, "dm355evm_keys",
353 NULL, 0, true, client->irq);
354 if (IS_ERR(child))
355 return PTR_ERR(child);
356 }
357
358 return 0;
359 }
360
361 /*----------------------------------------------------------------------*/
362
dm355evm_command(unsigned command)363 static void dm355evm_command(unsigned command)
364 {
365 int status;
366
367 status = dm355evm_msp_write(command, DM355EVM_MSP_COMMAND);
368 if (status < 0)
369 dev_err(&msp430->dev, "command %d failure %d\n",
370 command, status);
371 }
372
dm355evm_power_off(void)373 static void dm355evm_power_off(void)
374 {
375 dm355evm_command(MSP_COMMAND_POWEROFF);
376 }
377
dm355evm_msp_remove(struct i2c_client * client)378 static int dm355evm_msp_remove(struct i2c_client *client)
379 {
380 pm_power_off = NULL;
381 msp430 = NULL;
382 return 0;
383 }
384
385 static int
dm355evm_msp_probe(struct i2c_client * client,const struct i2c_device_id * id)386 dm355evm_msp_probe(struct i2c_client *client, const struct i2c_device_id *id)
387 {
388 int status;
389 const char *video = msp_has_tvp() ? "TVP5146" : "imager";
390
391 if (msp430)
392 return -EBUSY;
393 msp430 = client;
394
395 /* display revision status; doubles as sanity check */
396 status = dm355evm_msp_read(DM355EVM_MSP_FIRMREV);
397 if (status < 0)
398 goto fail;
399 dev_info(&client->dev, "firmware v.%02X, %s as video-in\n",
400 status, video);
401
402 /* mux video input: either tvp5146 or some external imager */
403 status = dm355evm_msp_write(msp_has_tvp() ? 0 : MSP_VIDEO_IMAGER,
404 DM355EVM_MSP_VIDEO_IN);
405 if (status < 0)
406 dev_warn(&client->dev, "error %d muxing %s as video-in\n",
407 status, video);
408
409 /* init LED cache, and turn off the LEDs */
410 msp_led_cache = 0xff;
411 dm355evm_msp_write(msp_led_cache, DM355EVM_MSP_LED);
412
413 /* export capabilities we support */
414 status = add_children(client);
415 if (status < 0)
416 goto fail;
417
418 /* PM hookup */
419 pm_power_off = dm355evm_power_off;
420
421 return 0;
422
423 fail:
424 /* FIXME remove children ... */
425 dm355evm_msp_remove(client);
426 return status;
427 }
428
429 static const struct i2c_device_id dm355evm_msp_ids[] = {
430 { "dm355evm_msp", 0 },
431 { /* end of list */ },
432 };
433 MODULE_DEVICE_TABLE(i2c, dm355evm_msp_ids);
434
435 static struct i2c_driver dm355evm_msp_driver = {
436 .driver.name = "dm355evm_msp",
437 .id_table = dm355evm_msp_ids,
438 .probe = dm355evm_msp_probe,
439 .remove = dm355evm_msp_remove,
440 };
441
dm355evm_msp_init(void)442 static int __init dm355evm_msp_init(void)
443 {
444 return i2c_add_driver(&dm355evm_msp_driver);
445 }
446 subsys_initcall(dm355evm_msp_init);
447
dm355evm_msp_exit(void)448 static void __exit dm355evm_msp_exit(void)
449 {
450 i2c_del_driver(&dm355evm_msp_driver);
451 }
452 module_exit(dm355evm_msp_exit);
453
454 MODULE_DESCRIPTION("Interface to MSP430 firmware on DM355EVM");
455 MODULE_LICENSE("GPL");
456