David Brownell | 0931a4c | 2008-12-22 12:05:27 +0100 | [diff] [blame] | 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/err.h> |
| 17 | #include <linux/gpio.h> |
| 18 | #include <linux/leds.h> |
| 19 | #include <linux/i2c.h> |
| 20 | #include <linux/i2c/dm355evm_msp.h> |
| 21 | |
| 22 | |
| 23 | /* |
| 24 | * The DM355 is a DaVinci chip with video support but no C64+ DSP. Its |
| 25 | * EVM board has an MSP430 programmed with firmware for various board |
| 26 | * support functions. This driver exposes some of them directly, and |
| 27 | * supports other drivers (e.g. RTC, input) for more complex access. |
| 28 | * |
| 29 | * Because this firmware is entirely board-specific, this file embeds |
| 30 | * knowledge that would be passed as platform_data in a generic driver. |
| 31 | * |
| 32 | * This driver was tested with firmware revision A4. |
| 33 | */ |
| 34 | |
| 35 | #if defined(CONFIG_KEYBOARD_DM355EVM) \ |
| 36 | || defined(CONFIG_KEYBOARD_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 | */ |
| 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 | */ |
| 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 | }; |
| 111 | |
| 112 | #define MSP_GPIO_REG(offset) (msp_gpios[(offset)] >> 3) |
| 113 | #define MSP_GPIO_MASK(offset) BIT(msp_gpios[(offset)] & 0x07) |
| 114 | |
| 115 | static int msp_gpio_in(struct gpio_chip *chip, unsigned offset) |
| 116 | { |
| 117 | switch (MSP_GPIO_REG(offset)) { |
| 118 | case DM355EVM_MSP_SWITCH1: |
| 119 | case DM355EVM_MSP_SWITCH2: |
| 120 | case DM355EVM_MSP_SDMMC: |
| 121 | return 0; |
| 122 | default: |
| 123 | return -EINVAL; |
| 124 | } |
| 125 | } |
| 126 | |
| 127 | static u8 msp_led_cache; |
| 128 | |
| 129 | static int msp_gpio_get(struct gpio_chip *chip, unsigned offset) |
| 130 | { |
| 131 | int reg, status; |
| 132 | |
| 133 | reg = MSP_GPIO_REG(offset); |
| 134 | status = dm355evm_msp_read(reg); |
| 135 | if (status < 0) |
| 136 | return status; |
| 137 | if (reg == DM355EVM_MSP_LED) |
| 138 | msp_led_cache = status; |
| 139 | return status & MSP_GPIO_MASK(offset); |
| 140 | } |
| 141 | |
| 142 | static int msp_gpio_out(struct gpio_chip *chip, unsigned offset, int value) |
| 143 | { |
| 144 | int mask, bits; |
| 145 | |
| 146 | /* NOTE: there are some other signals that could be |
| 147 | * packaged as output GPIOs, but they aren't as useful |
| 148 | * as the LEDs ... so for now we don't. |
| 149 | */ |
| 150 | if (MSP_GPIO_REG(offset) != DM355EVM_MSP_LED) |
| 151 | return -EINVAL; |
| 152 | |
| 153 | mask = MSP_GPIO_MASK(offset); |
| 154 | bits = msp_led_cache; |
| 155 | |
| 156 | bits &= ~mask; |
| 157 | if (value) |
| 158 | bits |= mask; |
| 159 | msp_led_cache = bits; |
| 160 | |
| 161 | return dm355evm_msp_write(bits, DM355EVM_MSP_LED); |
| 162 | } |
| 163 | |
| 164 | static void msp_gpio_set(struct gpio_chip *chip, unsigned offset, int value) |
| 165 | { |
| 166 | msp_gpio_out(chip, offset, value); |
| 167 | } |
| 168 | |
| 169 | static struct gpio_chip dm355evm_msp_gpio = { |
| 170 | .label = "dm355evm_msp", |
| 171 | .owner = THIS_MODULE, |
| 172 | .direction_input = msp_gpio_in, |
| 173 | .get = msp_gpio_get, |
| 174 | .direction_output = msp_gpio_out, |
| 175 | .set = msp_gpio_set, |
| 176 | .base = -EINVAL, /* dynamic assignment */ |
| 177 | .ngpio = ARRAY_SIZE(msp_gpios), |
| 178 | .can_sleep = true, |
| 179 | }; |
| 180 | |
| 181 | /*----------------------------------------------------------------------*/ |
| 182 | |
| 183 | static struct device *add_child(struct i2c_client *client, const char *name, |
| 184 | void *pdata, unsigned pdata_len, |
| 185 | bool can_wakeup, int irq) |
| 186 | { |
| 187 | struct platform_device *pdev; |
| 188 | int status; |
| 189 | |
| 190 | pdev = platform_device_alloc(name, -1); |
| 191 | if (!pdev) { |
| 192 | dev_dbg(&client->dev, "can't alloc dev\n"); |
| 193 | status = -ENOMEM; |
| 194 | goto err; |
| 195 | } |
| 196 | |
| 197 | device_init_wakeup(&pdev->dev, can_wakeup); |
| 198 | pdev->dev.parent = &client->dev; |
| 199 | |
| 200 | if (pdata) { |
| 201 | status = platform_device_add_data(pdev, pdata, pdata_len); |
| 202 | if (status < 0) { |
| 203 | dev_dbg(&pdev->dev, "can't add platform_data\n"); |
| 204 | goto err; |
| 205 | } |
| 206 | } |
| 207 | |
| 208 | if (irq) { |
| 209 | struct resource r = { |
| 210 | .start = irq, |
| 211 | .flags = IORESOURCE_IRQ, |
| 212 | }; |
| 213 | |
| 214 | status = platform_device_add_resources(pdev, &r, 1); |
| 215 | if (status < 0) { |
| 216 | dev_dbg(&pdev->dev, "can't add irq\n"); |
| 217 | goto err; |
| 218 | } |
| 219 | } |
| 220 | |
| 221 | status = platform_device_add(pdev); |
| 222 | |
| 223 | err: |
| 224 | if (status < 0) { |
| 225 | platform_device_put(pdev); |
| 226 | dev_err(&client->dev, "can't add %s dev\n", name); |
| 227 | return ERR_PTR(status); |
| 228 | } |
| 229 | return &pdev->dev; |
| 230 | } |
| 231 | |
| 232 | static int add_children(struct i2c_client *client) |
| 233 | { |
| 234 | static const struct { |
| 235 | int offset; |
| 236 | char *label; |
| 237 | } config_inputs[] = { |
| 238 | /* 8 == right after the LEDs */ |
| 239 | { 8 + 0, "sw6_1", }, |
| 240 | { 8 + 1, "sw6_2", }, |
| 241 | { 8 + 2, "sw6_3", }, |
| 242 | { 8 + 3, "sw6_4", }, |
| 243 | { 8 + 4, "NTSC/nPAL", }, |
| 244 | }; |
| 245 | |
| 246 | struct device *child; |
| 247 | int status; |
| 248 | int i; |
| 249 | |
| 250 | /* GPIO-ish stuff */ |
| 251 | dm355evm_msp_gpio.dev = &client->dev; |
| 252 | status = gpiochip_add(&dm355evm_msp_gpio); |
| 253 | if (status < 0) |
| 254 | return status; |
| 255 | |
| 256 | /* LED output */ |
| 257 | if (msp_has_leds()) { |
| 258 | #define GPIO_LED(l) .name = l, .active_low = true |
| 259 | static struct gpio_led evm_leds[] = { |
| 260 | { GPIO_LED("dm355evm::ds14"), |
| 261 | .default_trigger = "heartbeat", }, |
| 262 | { GPIO_LED("dm355evm::ds15"), |
| 263 | .default_trigger = "mmc0", }, |
| 264 | { GPIO_LED("dm355evm::ds16"), |
| 265 | /* could also be a CE-ATA drive */ |
| 266 | .default_trigger = "mmc1", }, |
| 267 | { GPIO_LED("dm355evm::ds17"), |
| 268 | .default_trigger = "nand-disk", }, |
| 269 | { GPIO_LED("dm355evm::ds18"), }, |
| 270 | { GPIO_LED("dm355evm::ds19"), }, |
| 271 | { GPIO_LED("dm355evm::ds20"), }, |
| 272 | { GPIO_LED("dm355evm::ds21"), }, |
| 273 | }; |
| 274 | #undef GPIO_LED |
| 275 | |
| 276 | struct gpio_led_platform_data evm_led_data = { |
| 277 | .num_leds = ARRAY_SIZE(evm_leds), |
| 278 | .leds = evm_leds, |
| 279 | }; |
| 280 | |
| 281 | for (i = 0; i < ARRAY_SIZE(evm_leds); i++) |
| 282 | evm_leds[i].gpio = i + dm355evm_msp_gpio.base; |
| 283 | |
| 284 | /* NOTE: these are the only fully programmable LEDs |
| 285 | * on the board, since GPIO-61/ds22 (and many signals |
| 286 | * going to DC7) must be used for AEMIF address lines |
| 287 | * unless the top 1 GB of NAND is unused... |
| 288 | */ |
| 289 | child = add_child(client, "leds-gpio", |
| 290 | &evm_led_data, sizeof(evm_led_data), |
| 291 | false, 0); |
| 292 | if (IS_ERR(child)) |
| 293 | return PTR_ERR(child); |
| 294 | } |
| 295 | |
| 296 | /* configuration inputs */ |
| 297 | for (i = 0; i < ARRAY_SIZE(config_inputs); i++) { |
| 298 | int gpio = dm355evm_msp_gpio.base + config_inputs[i].offset; |
| 299 | |
| 300 | gpio_request(gpio, config_inputs[i].label); |
| 301 | gpio_direction_input(gpio); |
| 302 | |
| 303 | /* make it easy for userspace to see these */ |
| 304 | gpio_export(gpio, false); |
| 305 | } |
| 306 | |
| 307 | /* RTC is a 32 bit counter, no alarm */ |
| 308 | if (msp_has_rtc()) { |
| 309 | child = add_child(client, "rtc-dm355evm", |
| 310 | NULL, 0, false, 0); |
| 311 | if (IS_ERR(child)) |
| 312 | return PTR_ERR(child); |
| 313 | } |
| 314 | |
| 315 | /* input from buttons and IR remote (uses the IRQ) */ |
| 316 | if (msp_has_keyboard()) { |
| 317 | child = add_child(client, "dm355evm_keys", |
| 318 | NULL, 0, true, client->irq); |
| 319 | if (IS_ERR(child)) |
| 320 | return PTR_ERR(child); |
| 321 | } |
| 322 | |
| 323 | return 0; |
| 324 | } |
| 325 | |
| 326 | /*----------------------------------------------------------------------*/ |
| 327 | |
| 328 | static void dm355evm_command(unsigned command) |
| 329 | { |
| 330 | int status; |
| 331 | |
| 332 | status = dm355evm_msp_write(command, DM355EVM_MSP_COMMAND); |
| 333 | if (status < 0) |
| 334 | dev_err(&msp430->dev, "command %d failure %d\n", |
| 335 | command, status); |
| 336 | } |
| 337 | |
| 338 | static void dm355evm_power_off(void) |
| 339 | { |
| 340 | dm355evm_command(MSP_COMMAND_POWEROFF); |
| 341 | } |
| 342 | |
| 343 | static int dm355evm_msp_remove(struct i2c_client *client) |
| 344 | { |
| 345 | pm_power_off = NULL; |
| 346 | msp430 = NULL; |
| 347 | return 0; |
| 348 | } |
| 349 | |
| 350 | static int |
| 351 | dm355evm_msp_probe(struct i2c_client *client, const struct i2c_device_id *id) |
| 352 | { |
| 353 | int status; |
| 354 | const char *video = msp_has_tvp() ? "TVP5146" : "imager"; |
| 355 | |
| 356 | if (msp430) |
| 357 | return -EBUSY; |
| 358 | msp430 = client; |
| 359 | |
| 360 | /* display revision status; doubles as sanity check */ |
| 361 | status = dm355evm_msp_read(DM355EVM_MSP_FIRMREV); |
| 362 | if (status < 0) |
| 363 | goto fail; |
| 364 | dev_info(&client->dev, "firmware v.%02X, %s as video-in\n", |
| 365 | status, video); |
| 366 | |
| 367 | /* mux video input: either tvp5146 or some external imager */ |
| 368 | status = dm355evm_msp_write(msp_has_tvp() ? 0 : MSP_VIDEO_IMAGER, |
| 369 | DM355EVM_MSP_VIDEO_IN); |
| 370 | if (status < 0) |
| 371 | dev_warn(&client->dev, "error %d muxing %s as video-in\n", |
| 372 | status, video); |
| 373 | |
| 374 | /* init LED cache, and turn off the LEDs */ |
| 375 | msp_led_cache = 0xff; |
| 376 | dm355evm_msp_write(msp_led_cache, DM355EVM_MSP_LED); |
| 377 | |
| 378 | /* export capabilities we support */ |
| 379 | status = add_children(client); |
| 380 | if (status < 0) |
| 381 | goto fail; |
| 382 | |
| 383 | /* PM hookup */ |
| 384 | pm_power_off = dm355evm_power_off; |
| 385 | |
| 386 | return 0; |
| 387 | |
| 388 | fail: |
| 389 | /* FIXME remove children ... */ |
| 390 | dm355evm_msp_remove(client); |
| 391 | return status; |
| 392 | } |
| 393 | |
| 394 | static const struct i2c_device_id dm355evm_msp_ids[] = { |
| 395 | { "dm355evm_msp", 0 }, |
| 396 | { /* end of list */ }, |
| 397 | }; |
| 398 | MODULE_DEVICE_TABLE(i2c, dm355evm_msp_ids); |
| 399 | |
| 400 | static struct i2c_driver dm355evm_msp_driver = { |
| 401 | .driver.name = "dm355evm_msp", |
| 402 | .id_table = dm355evm_msp_ids, |
| 403 | .probe = dm355evm_msp_probe, |
| 404 | .remove = dm355evm_msp_remove, |
| 405 | }; |
| 406 | |
| 407 | static int __init dm355evm_msp_init(void) |
| 408 | { |
| 409 | return i2c_add_driver(&dm355evm_msp_driver); |
| 410 | } |
| 411 | subsys_initcall(dm355evm_msp_init); |
| 412 | |
| 413 | static void __exit dm355evm_msp_exit(void) |
| 414 | { |
| 415 | i2c_del_driver(&dm355evm_msp_driver); |
| 416 | } |
| 417 | module_exit(dm355evm_msp_exit); |
| 418 | |
| 419 | MODULE_DESCRIPTION("Interface to MSP430 firmware on DM355EVM"); |
| 420 | MODULE_LICENSE("GPL"); |