1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Digital I/O driver for Technologic Systems TS-5500 4 * 5 * Copyright (c) 2012 Savoir-faire Linux Inc. 6 * Vivien Didelot <vivien.didelot@savoirfairelinux.com> 7 * 8 * Technologic Systems platforms have pin blocks, exposing several Digital 9 * Input/Output lines (DIO). This driver aims to support single pin blocks. 10 * In that sense, the support is not limited to the TS-5500 blocks. 11 * Actually, the following platforms have DIO support: 12 * 13 * TS-5500: 14 * Documentation: http://wiki.embeddedarm.com/wiki/TS-5500 15 * Blocks: DIO1, DIO2 and LCD port. 16 * 17 * TS-5600: 18 * Documentation: http://wiki.embeddedarm.com/wiki/TS-5600 19 * Blocks: LCD port (identical to TS-5500 LCD). 20 */ 21 22 #include <linux/bitops.h> 23 #include <linux/gpio/driver.h> 24 #include <linux/io.h> 25 #include <linux/module.h> 26 #include <linux/platform_device.h> 27 #include <linux/slab.h> 28 29 /* List of supported Technologic Systems platforms DIO blocks */ 30 enum ts5500_blocks { TS5500_DIO1, TS5500_DIO2, TS5500_LCD, TS5600_LCD }; 31 32 struct ts5500_priv { 33 const struct ts5500_dio *pinout; 34 struct gpio_chip gpio_chip; 35 spinlock_t lock; 36 bool strap; 37 u8 hwirq; 38 }; 39 40 /* 41 * Hex 7D is used to control several blocks (e.g. DIO2 and LCD port). 42 * This flag ensures that the region has been requested by this driver. 43 */ 44 static bool hex7d_reserved; 45 46 /* 47 * This structure is used to describe capabilities of DIO lines, 48 * such as available directions and connected interrupt (if any). 49 */ 50 struct ts5500_dio { 51 const u8 value_addr; 52 const u8 value_mask; 53 const u8 control_addr; 54 const u8 control_mask; 55 const bool no_input; 56 const bool no_output; 57 const u8 irq; 58 }; 59 60 #define TS5500_DIO_IN_OUT(vaddr, vbit, caddr, cbit) \ 61 { \ 62 .value_addr = vaddr, \ 63 .value_mask = BIT(vbit), \ 64 .control_addr = caddr, \ 65 .control_mask = BIT(cbit), \ 66 } 67 68 #define TS5500_DIO_IN(addr, bit) \ 69 { \ 70 .value_addr = addr, \ 71 .value_mask = BIT(bit), \ 72 .no_output = true, \ 73 } 74 75 #define TS5500_DIO_IN_IRQ(addr, bit, _irq) \ 76 { \ 77 .value_addr = addr, \ 78 .value_mask = BIT(bit), \ 79 .no_output = true, \ 80 .irq = _irq, \ 81 } 82 83 #define TS5500_DIO_OUT(addr, bit) \ 84 { \ 85 .value_addr = addr, \ 86 .value_mask = BIT(bit), \ 87 .no_input = true, \ 88 } 89 90 /* 91 * Input/Output DIO lines are programmed in groups of 4. Their values are 92 * available through 4 consecutive bits in a value port, whereas the direction 93 * of these 4 lines is driven by only 1 bit in a control port. 94 */ 95 #define TS5500_DIO_GROUP(vaddr, vbitfrom, caddr, cbit) \ 96 TS5500_DIO_IN_OUT(vaddr, vbitfrom + 0, caddr, cbit), \ 97 TS5500_DIO_IN_OUT(vaddr, vbitfrom + 1, caddr, cbit), \ 98 TS5500_DIO_IN_OUT(vaddr, vbitfrom + 2, caddr, cbit), \ 99 TS5500_DIO_IN_OUT(vaddr, vbitfrom + 3, caddr, cbit) 100 101 /* 102 * TS-5500 DIO1 block 103 * 104 * value control dir hw 105 * addr bit addr bit in out irq name pin offset 106 * 107 * 0x7b 0 0x7a 0 x x DIO1_0 1 0 108 * 0x7b 1 0x7a 0 x x DIO1_1 3 1 109 * 0x7b 2 0x7a 0 x x DIO1_2 5 2 110 * 0x7b 3 0x7a 0 x x DIO1_3 7 3 111 * 0x7b 4 0x7a 1 x x DIO1_4 9 4 112 * 0x7b 5 0x7a 1 x x DIO1_5 11 5 113 * 0x7b 6 0x7a 1 x x DIO1_6 13 6 114 * 0x7b 7 0x7a 1 x x DIO1_7 15 7 115 * 0x7c 0 0x7a 5 x x DIO1_8 4 8 116 * 0x7c 1 0x7a 5 x x DIO1_9 6 9 117 * 0x7c 2 0x7a 5 x x DIO1_10 8 10 118 * 0x7c 3 0x7a 5 x x DIO1_11 10 11 119 * 0x7c 4 x DIO1_12 12 12 120 * 0x7c 5 x 7 DIO1_13 14 13 121 */ 122 static const struct ts5500_dio ts5500_dio1[] = { 123 TS5500_DIO_GROUP(0x7b, 0, 0x7a, 0), 124 TS5500_DIO_GROUP(0x7b, 4, 0x7a, 1), 125 TS5500_DIO_GROUP(0x7c, 0, 0x7a, 5), 126 TS5500_DIO_IN(0x7c, 4), 127 TS5500_DIO_IN_IRQ(0x7c, 5, 7), 128 }; 129 130 /* 131 * TS-5500 DIO2 block 132 * 133 * value control dir hw 134 * addr bit addr bit in out irq name pin offset 135 * 136 * 0x7e 0 0x7d 0 x x DIO2_0 1 0 137 * 0x7e 1 0x7d 0 x x DIO2_1 3 1 138 * 0x7e 2 0x7d 0 x x DIO2_2 5 2 139 * 0x7e 3 0x7d 0 x x DIO2_3 7 3 140 * 0x7e 4 0x7d 1 x x DIO2_4 9 4 141 * 0x7e 5 0x7d 1 x x DIO2_5 11 5 142 * 0x7e 6 0x7d 1 x x DIO2_6 13 6 143 * 0x7e 7 0x7d 1 x x DIO2_7 15 7 144 * 0x7f 0 0x7d 5 x x DIO2_8 4 8 145 * 0x7f 1 0x7d 5 x x DIO2_9 6 9 146 * 0x7f 2 0x7d 5 x x DIO2_10 8 10 147 * 0x7f 3 0x7d 5 x x DIO2_11 10 11 148 * 0x7f 4 x 6 DIO2_13 14 12 149 */ 150 static const struct ts5500_dio ts5500_dio2[] = { 151 TS5500_DIO_GROUP(0x7e, 0, 0x7d, 0), 152 TS5500_DIO_GROUP(0x7e, 4, 0x7d, 1), 153 TS5500_DIO_GROUP(0x7f, 0, 0x7d, 5), 154 TS5500_DIO_IN_IRQ(0x7f, 4, 6), 155 }; 156 157 /* 158 * TS-5500 LCD port used as DIO block 159 * TS-5600 LCD port is identical 160 * 161 * value control dir hw 162 * addr bit addr bit in out irq name pin offset 163 * 164 * 0x72 0 0x7d 2 x x LCD_0 8 0 165 * 0x72 1 0x7d 2 x x LCD_1 7 1 166 * 0x72 2 0x7d 2 x x LCD_2 10 2 167 * 0x72 3 0x7d 2 x x LCD_3 9 3 168 * 0x72 4 0x7d 3 x x LCD_4 12 4 169 * 0x72 5 0x7d 3 x x LCD_5 11 5 170 * 0x72 6 0x7d 3 x x LCD_6 14 6 171 * 0x72 7 0x7d 3 x x LCD_7 13 7 172 * 0x73 0 x LCD_EN 5 8 173 * 0x73 6 x LCD_WR 6 9 174 * 0x73 7 x 1 LCD_RS 3 10 175 */ 176 static const struct ts5500_dio ts5500_lcd[] = { 177 TS5500_DIO_GROUP(0x72, 0, 0x7d, 2), 178 TS5500_DIO_GROUP(0x72, 4, 0x7d, 3), 179 TS5500_DIO_OUT(0x73, 0), 180 TS5500_DIO_IN(0x73, 6), 181 TS5500_DIO_IN_IRQ(0x73, 7, 1), 182 }; 183 184 static inline void ts5500_set_mask(u8 mask, u8 addr) 185 { 186 u8 val = inb(addr); 187 val |= mask; 188 outb(val, addr); 189 } 190 191 static inline void ts5500_clear_mask(u8 mask, u8 addr) 192 { 193 u8 val = inb(addr); 194 val &= ~mask; 195 outb(val, addr); 196 } 197 198 static int ts5500_gpio_input(struct gpio_chip *chip, unsigned offset) 199 { 200 struct ts5500_priv *priv = gpiochip_get_data(chip); 201 const struct ts5500_dio line = priv->pinout[offset]; 202 unsigned long flags; 203 204 if (line.no_input) 205 return -ENXIO; 206 207 if (line.no_output) 208 return 0; 209 210 spin_lock_irqsave(&priv->lock, flags); 211 ts5500_clear_mask(line.control_mask, line.control_addr); 212 spin_unlock_irqrestore(&priv->lock, flags); 213 214 return 0; 215 } 216 217 static int ts5500_gpio_get(struct gpio_chip *chip, unsigned offset) 218 { 219 struct ts5500_priv *priv = gpiochip_get_data(chip); 220 const struct ts5500_dio line = priv->pinout[offset]; 221 222 return !!(inb(line.value_addr) & line.value_mask); 223 } 224 225 static int ts5500_gpio_output(struct gpio_chip *chip, unsigned offset, int val) 226 { 227 struct ts5500_priv *priv = gpiochip_get_data(chip); 228 const struct ts5500_dio line = priv->pinout[offset]; 229 unsigned long flags; 230 231 if (line.no_output) 232 return -ENXIO; 233 234 spin_lock_irqsave(&priv->lock, flags); 235 if (!line.no_input) 236 ts5500_set_mask(line.control_mask, line.control_addr); 237 238 if (val) 239 ts5500_set_mask(line.value_mask, line.value_addr); 240 else 241 ts5500_clear_mask(line.value_mask, line.value_addr); 242 spin_unlock_irqrestore(&priv->lock, flags); 243 244 return 0; 245 } 246 247 static void ts5500_gpio_set(struct gpio_chip *chip, unsigned offset, int val) 248 { 249 struct ts5500_priv *priv = gpiochip_get_data(chip); 250 const struct ts5500_dio line = priv->pinout[offset]; 251 unsigned long flags; 252 253 spin_lock_irqsave(&priv->lock, flags); 254 if (val) 255 ts5500_set_mask(line.value_mask, line.value_addr); 256 else 257 ts5500_clear_mask(line.value_mask, line.value_addr); 258 spin_unlock_irqrestore(&priv->lock, flags); 259 } 260 261 static int ts5500_gpio_to_irq(struct gpio_chip *chip, unsigned offset) 262 { 263 struct ts5500_priv *priv = gpiochip_get_data(chip); 264 const struct ts5500_dio *block = priv->pinout; 265 const struct ts5500_dio line = block[offset]; 266 267 /* Only one pin is connected to an interrupt */ 268 if (line.irq) 269 return line.irq; 270 271 /* As this pin is input-only, we may strap it to another in/out pin */ 272 if (priv->strap) 273 return priv->hwirq; 274 275 return -ENXIO; 276 } 277 278 static int ts5500_enable_irq(struct ts5500_priv *priv) 279 { 280 int ret = 0; 281 unsigned long flags; 282 283 spin_lock_irqsave(&priv->lock, flags); 284 if (priv->hwirq == 7) 285 ts5500_set_mask(BIT(7), 0x7a); /* DIO1_13 on IRQ7 */ 286 else if (priv->hwirq == 6) 287 ts5500_set_mask(BIT(7), 0x7d); /* DIO2_13 on IRQ6 */ 288 else if (priv->hwirq == 1) 289 ts5500_set_mask(BIT(6), 0x7d); /* LCD_RS on IRQ1 */ 290 else 291 ret = -EINVAL; 292 spin_unlock_irqrestore(&priv->lock, flags); 293 294 return ret; 295 } 296 297 static void ts5500_disable_irq(struct ts5500_priv *priv) 298 { 299 unsigned long flags; 300 301 spin_lock_irqsave(&priv->lock, flags); 302 if (priv->hwirq == 7) 303 ts5500_clear_mask(BIT(7), 0x7a); /* DIO1_13 on IRQ7 */ 304 else if (priv->hwirq == 6) 305 ts5500_clear_mask(BIT(7), 0x7d); /* DIO2_13 on IRQ6 */ 306 else if (priv->hwirq == 1) 307 ts5500_clear_mask(BIT(6), 0x7d); /* LCD_RS on IRQ1 */ 308 else 309 dev_err(priv->gpio_chip.parent, "invalid hwirq %d\n", 310 priv->hwirq); 311 spin_unlock_irqrestore(&priv->lock, flags); 312 } 313 314 static int ts5500_dio_probe(struct platform_device *pdev) 315 { 316 enum ts5500_blocks block = platform_get_device_id(pdev)->driver_data; 317 struct device *dev = &pdev->dev; 318 const char *name = dev_name(dev); 319 struct ts5500_priv *priv; 320 unsigned long flags; 321 int ret; 322 323 ret = platform_get_irq(pdev, 0); 324 if (ret < 0) 325 return ret; 326 327 priv = devm_kzalloc(dev, sizeof(struct ts5500_priv), GFP_KERNEL); 328 if (!priv) 329 return -ENOMEM; 330 331 platform_set_drvdata(pdev, priv); 332 priv->hwirq = ret; 333 spin_lock_init(&priv->lock); 334 335 priv->gpio_chip.owner = THIS_MODULE; 336 priv->gpio_chip.label = name; 337 priv->gpio_chip.parent = dev; 338 priv->gpio_chip.direction_input = ts5500_gpio_input; 339 priv->gpio_chip.direction_output = ts5500_gpio_output; 340 priv->gpio_chip.get = ts5500_gpio_get; 341 priv->gpio_chip.set = ts5500_gpio_set; 342 priv->gpio_chip.to_irq = ts5500_gpio_to_irq; 343 priv->gpio_chip.base = -1; 344 345 switch (block) { 346 case TS5500_DIO1: 347 priv->pinout = ts5500_dio1; 348 priv->gpio_chip.ngpio = ARRAY_SIZE(ts5500_dio1); 349 350 if (!devm_request_region(dev, 0x7a, 3, name)) { 351 dev_err(dev, "failed to request %s ports\n", name); 352 return -EBUSY; 353 } 354 break; 355 case TS5500_DIO2: 356 priv->pinout = ts5500_dio2; 357 priv->gpio_chip.ngpio = ARRAY_SIZE(ts5500_dio2); 358 359 if (!devm_request_region(dev, 0x7e, 2, name)) { 360 dev_err(dev, "failed to request %s ports\n", name); 361 return -EBUSY; 362 } 363 364 if (hex7d_reserved) 365 break; 366 367 if (!devm_request_region(dev, 0x7d, 1, name)) { 368 dev_err(dev, "failed to request %s 7D\n", name); 369 return -EBUSY; 370 } 371 372 hex7d_reserved = true; 373 break; 374 case TS5500_LCD: 375 case TS5600_LCD: 376 priv->pinout = ts5500_lcd; 377 priv->gpio_chip.ngpio = ARRAY_SIZE(ts5500_lcd); 378 379 if (!devm_request_region(dev, 0x72, 2, name)) { 380 dev_err(dev, "failed to request %s ports\n", name); 381 return -EBUSY; 382 } 383 384 if (!hex7d_reserved) { 385 if (!devm_request_region(dev, 0x7d, 1, name)) { 386 dev_err(dev, "failed to request %s 7D\n", name); 387 return -EBUSY; 388 } 389 390 hex7d_reserved = true; 391 } 392 393 /* Ensure usage of LCD port as DIO */ 394 spin_lock_irqsave(&priv->lock, flags); 395 ts5500_clear_mask(BIT(4), 0x7d); 396 spin_unlock_irqrestore(&priv->lock, flags); 397 break; 398 } 399 400 ret = devm_gpiochip_add_data(dev, &priv->gpio_chip, priv); 401 if (ret) { 402 dev_err(dev, "failed to register the gpio chip\n"); 403 return ret; 404 } 405 406 ret = ts5500_enable_irq(priv); 407 if (ret) { 408 dev_err(dev, "invalid interrupt %d\n", priv->hwirq); 409 return ret; 410 } 411 412 return 0; 413 } 414 415 static int ts5500_dio_remove(struct platform_device *pdev) 416 { 417 struct ts5500_priv *priv = platform_get_drvdata(pdev); 418 419 ts5500_disable_irq(priv); 420 421 return 0; 422 } 423 424 static const struct platform_device_id ts5500_dio_ids[] = { 425 { "ts5500-dio1", TS5500_DIO1 }, 426 { "ts5500-dio2", TS5500_DIO2 }, 427 { "ts5500-dio-lcd", TS5500_LCD }, 428 { "ts5600-dio-lcd", TS5600_LCD }, 429 { } 430 }; 431 MODULE_DEVICE_TABLE(platform, ts5500_dio_ids); 432 433 static struct platform_driver ts5500_dio_driver = { 434 .driver = { 435 .name = "ts5500-dio", 436 }, 437 .probe = ts5500_dio_probe, 438 .remove = ts5500_dio_remove, 439 .id_table = ts5500_dio_ids, 440 }; 441 442 module_platform_driver(ts5500_dio_driver); 443 444 MODULE_LICENSE("GPL"); 445 MODULE_AUTHOR("Savoir-faire Linux Inc. <kernel@savoirfairelinux.com>"); 446 MODULE_DESCRIPTION("Technologic Systems TS-5500 Digital I/O driver"); 447