Hans-Christian Egtvedt | 864fe73 | 2009-04-18 18:45:06 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Atmel AT91 and AVR32 continuous touch screen driver for Wolfson WM97xx AC97 |
| 3 | * codecs. |
| 4 | * |
| 5 | * Copyright (C) 2008 - 2009 Atmel Corporation |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify it |
| 8 | * under the terms of the GNU General Public License version 2 as published by |
| 9 | * the Free Software Foundation. |
| 10 | */ |
| 11 | #include <linux/module.h> |
| 12 | #include <linux/moduleparam.h> |
| 13 | #include <linux/kernel.h> |
| 14 | #include <linux/init.h> |
| 15 | #include <linux/delay.h> |
| 16 | #include <linux/irq.h> |
| 17 | #include <linux/interrupt.h> |
| 18 | #include <linux/wm97xx.h> |
| 19 | #include <linux/timer.h> |
| 20 | #include <linux/gpio.h> |
| 21 | #include <linux/io.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 22 | #include <linux/slab.h> |
Hans-Christian Egtvedt | 864fe73 | 2009-04-18 18:45:06 -0700 | [diff] [blame] | 23 | |
| 24 | #define AC97C_ICA 0x10 |
| 25 | #define AC97C_CBRHR 0x30 |
| 26 | #define AC97C_CBSR 0x38 |
| 27 | #define AC97C_CBMR 0x3c |
| 28 | #define AC97C_IER 0x54 |
| 29 | #define AC97C_IDR 0x58 |
| 30 | |
| 31 | #define AC97C_RXRDY (1 << 4) |
| 32 | #define AC97C_OVRUN (1 << 5) |
| 33 | |
| 34 | #define AC97C_CMR_SIZE_20 (0 << 16) |
| 35 | #define AC97C_CMR_SIZE_18 (1 << 16) |
| 36 | #define AC97C_CMR_SIZE_16 (2 << 16) |
| 37 | #define AC97C_CMR_SIZE_10 (3 << 16) |
| 38 | #define AC97C_CMR_CEM_LITTLE (1 << 18) |
| 39 | #define AC97C_CMR_CEM_BIG (0 << 18) |
| 40 | #define AC97C_CMR_CENA (1 << 21) |
| 41 | |
| 42 | #define AC97C_INT_CBEVT (1 << 4) |
| 43 | |
| 44 | #define AC97C_SR_CAEVT (1 << 3) |
| 45 | |
| 46 | #define AC97C_CH_MASK(slot) \ |
| 47 | (0x7 << (3 * (slot - 3))) |
| 48 | #define AC97C_CH_ASSIGN(slot, channel) \ |
| 49 | (AC97C_CHANNEL_##channel << (3 * (slot - 3))) |
| 50 | #define AC97C_CHANNEL_NONE 0x0 |
| 51 | #define AC97C_CHANNEL_B 0x2 |
| 52 | |
| 53 | #define ac97c_writel(chip, reg, val) \ |
| 54 | __raw_writel((val), (chip)->regs + AC97C_##reg) |
| 55 | #define ac97c_readl(chip, reg) \ |
| 56 | __raw_readl((chip)->regs + AC97C_##reg) |
| 57 | |
| 58 | #ifdef CONFIG_CPU_AT32AP700X |
| 59 | #define ATMEL_WM97XX_AC97C_IOMEM (0xfff02800) |
| 60 | #define ATMEL_WM97XX_AC97C_IRQ (29) |
| 61 | #define ATMEL_WM97XX_GPIO_DEFAULT (32+16) /* Pin 16 on port B. */ |
| 62 | #else |
André Goddard Rosa | af901ca | 2009-11-14 13:09:05 -0200 | [diff] [blame] | 63 | #error Unknown CPU, this driver only supports AT32AP700X CPUs. |
Hans-Christian Egtvedt | 864fe73 | 2009-04-18 18:45:06 -0700 | [diff] [blame] | 64 | #endif |
| 65 | |
| 66 | struct continuous { |
| 67 | u16 id; /* codec id */ |
| 68 | u8 code; /* continuous code */ |
| 69 | u8 reads; /* number of coord reads per read cycle */ |
| 70 | u32 speed; /* number of coords per second */ |
| 71 | }; |
| 72 | |
| 73 | #define WM_READS(sp) ((sp / HZ) + 1) |
| 74 | |
| 75 | static const struct continuous cinfo[] = { |
| 76 | {WM9705_ID2, 0, WM_READS(94), 94}, |
| 77 | {WM9705_ID2, 1, WM_READS(188), 188}, |
| 78 | {WM9705_ID2, 2, WM_READS(375), 375}, |
| 79 | {WM9705_ID2, 3, WM_READS(750), 750}, |
| 80 | {WM9712_ID2, 0, WM_READS(94), 94}, |
| 81 | {WM9712_ID2, 1, WM_READS(188), 188}, |
| 82 | {WM9712_ID2, 2, WM_READS(375), 375}, |
| 83 | {WM9712_ID2, 3, WM_READS(750), 750}, |
| 84 | {WM9713_ID2, 0, WM_READS(94), 94}, |
| 85 | {WM9713_ID2, 1, WM_READS(120), 120}, |
| 86 | {WM9713_ID2, 2, WM_READS(154), 154}, |
| 87 | {WM9713_ID2, 3, WM_READS(188), 188}, |
| 88 | }; |
| 89 | |
| 90 | /* Continuous speed index. */ |
| 91 | static int sp_idx; |
| 92 | |
| 93 | /* |
| 94 | * Pen sampling frequency (Hz) in continuous mode. |
| 95 | */ |
| 96 | static int cont_rate = 188; |
| 97 | module_param(cont_rate, int, 0); |
| 98 | MODULE_PARM_DESC(cont_rate, "Sampling rate in continuous mode (Hz)"); |
| 99 | |
| 100 | /* |
| 101 | * Pen down detection. |
| 102 | * |
| 103 | * This driver can either poll or use an interrupt to indicate a pen down |
| 104 | * event. If the irq request fails then it will fall back to polling mode. |
| 105 | */ |
| 106 | static int pen_int = 1; |
| 107 | module_param(pen_int, int, 0); |
| 108 | MODULE_PARM_DESC(pen_int, "Pen down detection (1 = interrupt, 0 = polling)"); |
| 109 | |
| 110 | /* |
| 111 | * Pressure readback. |
| 112 | * |
| 113 | * Set to 1 to read back pen down pressure. |
| 114 | */ |
| 115 | static int pressure; |
| 116 | module_param(pressure, int, 0); |
| 117 | MODULE_PARM_DESC(pressure, "Pressure readback (1 = pressure, 0 = no pressure)"); |
| 118 | |
| 119 | /* |
| 120 | * AC97 touch data slot. |
| 121 | * |
| 122 | * Touch screen readback data ac97 slot. |
| 123 | */ |
| 124 | static int ac97_touch_slot = 5; |
| 125 | module_param(ac97_touch_slot, int, 0); |
| 126 | MODULE_PARM_DESC(ac97_touch_slot, "Touch screen data slot AC97 number"); |
| 127 | |
| 128 | /* |
| 129 | * GPIO line number. |
| 130 | * |
| 131 | * Set to GPIO number where the signal from the WM97xx device is hooked up. |
| 132 | */ |
| 133 | static int atmel_gpio_line = ATMEL_WM97XX_GPIO_DEFAULT; |
| 134 | module_param(atmel_gpio_line, int, 0); |
| 135 | MODULE_PARM_DESC(atmel_gpio_line, "GPIO line number connected to WM97xx"); |
| 136 | |
| 137 | struct atmel_wm97xx { |
| 138 | struct wm97xx *wm; |
| 139 | struct timer_list pen_timer; |
| 140 | void __iomem *regs; |
| 141 | unsigned long ac97c_irq; |
| 142 | unsigned long gpio_pen; |
| 143 | unsigned long gpio_irq; |
| 144 | unsigned short x; |
| 145 | unsigned short y; |
| 146 | }; |
| 147 | |
| 148 | static irqreturn_t atmel_wm97xx_channel_b_interrupt(int irq, void *dev_id) |
| 149 | { |
| 150 | struct atmel_wm97xx *atmel_wm97xx = dev_id; |
| 151 | struct wm97xx *wm = atmel_wm97xx->wm; |
| 152 | int status = ac97c_readl(atmel_wm97xx, CBSR); |
| 153 | irqreturn_t retval = IRQ_NONE; |
| 154 | |
| 155 | if (status & AC97C_OVRUN) { |
| 156 | dev_dbg(&wm->touch_dev->dev, "AC97C overrun\n"); |
| 157 | ac97c_readl(atmel_wm97xx, CBRHR); |
| 158 | retval = IRQ_HANDLED; |
| 159 | } else if (status & AC97C_RXRDY) { |
| 160 | u16 data; |
| 161 | u16 value; |
| 162 | u16 source; |
| 163 | u16 pen_down; |
| 164 | |
| 165 | data = ac97c_readl(atmel_wm97xx, CBRHR); |
| 166 | value = data & 0x0fff; |
Wolfram Sang | 2456689 | 2011-07-04 19:22:00 -0700 | [diff] [blame] | 167 | source = data & WM97XX_ADCSEL_MASK; |
Hans-Christian Egtvedt | 864fe73 | 2009-04-18 18:45:06 -0700 | [diff] [blame] | 168 | pen_down = (data & WM97XX_PEN_DOWN) >> 8; |
| 169 | |
| 170 | if (source == WM97XX_ADCSEL_X) |
| 171 | atmel_wm97xx->x = value; |
| 172 | if (source == WM97XX_ADCSEL_Y) |
| 173 | atmel_wm97xx->y = value; |
| 174 | |
| 175 | if (!pressure && source == WM97XX_ADCSEL_Y) { |
| 176 | input_report_abs(wm->input_dev, ABS_X, atmel_wm97xx->x); |
| 177 | input_report_abs(wm->input_dev, ABS_Y, atmel_wm97xx->y); |
| 178 | input_report_key(wm->input_dev, BTN_TOUCH, pen_down); |
| 179 | input_sync(wm->input_dev); |
| 180 | } else if (pressure && source == WM97XX_ADCSEL_PRES) { |
| 181 | input_report_abs(wm->input_dev, ABS_X, atmel_wm97xx->x); |
| 182 | input_report_abs(wm->input_dev, ABS_Y, atmel_wm97xx->y); |
| 183 | input_report_abs(wm->input_dev, ABS_PRESSURE, value); |
| 184 | input_report_key(wm->input_dev, BTN_TOUCH, value); |
| 185 | input_sync(wm->input_dev); |
| 186 | } |
| 187 | |
| 188 | retval = IRQ_HANDLED; |
| 189 | } |
| 190 | |
| 191 | return retval; |
| 192 | } |
| 193 | |
| 194 | static void atmel_wm97xx_acc_pen_up(struct wm97xx *wm) |
| 195 | { |
| 196 | struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(wm->touch_dev); |
| 197 | struct input_dev *input_dev = wm->input_dev; |
| 198 | int pen_down = gpio_get_value(atmel_wm97xx->gpio_pen); |
| 199 | |
| 200 | if (pen_down != 0) { |
| 201 | mod_timer(&atmel_wm97xx->pen_timer, |
| 202 | jiffies + msecs_to_jiffies(1)); |
| 203 | } else { |
| 204 | if (pressure) |
| 205 | input_report_abs(input_dev, ABS_PRESSURE, 0); |
| 206 | input_report_key(input_dev, BTN_TOUCH, 0); |
| 207 | input_sync(input_dev); |
| 208 | } |
| 209 | } |
| 210 | |
| 211 | static void atmel_wm97xx_pen_timer(unsigned long data) |
| 212 | { |
| 213 | atmel_wm97xx_acc_pen_up((struct wm97xx *)data); |
| 214 | } |
| 215 | |
| 216 | static int atmel_wm97xx_acc_startup(struct wm97xx *wm) |
| 217 | { |
| 218 | struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(wm->touch_dev); |
| 219 | int idx = 0; |
| 220 | |
| 221 | if (wm->ac97 == NULL) |
| 222 | return -ENODEV; |
| 223 | |
| 224 | for (idx = 0; idx < ARRAY_SIZE(cinfo); idx++) { |
| 225 | if (wm->id != cinfo[idx].id) |
| 226 | continue; |
| 227 | |
| 228 | sp_idx = idx; |
| 229 | |
| 230 | if (cont_rate <= cinfo[idx].speed) |
| 231 | break; |
| 232 | } |
| 233 | |
| 234 | wm->acc_rate = cinfo[sp_idx].code; |
| 235 | wm->acc_slot = ac97_touch_slot; |
| 236 | dev_info(&wm->touch_dev->dev, "atmel accelerated touchscreen driver, " |
| 237 | "%d samples/sec\n", cinfo[sp_idx].speed); |
| 238 | |
| 239 | if (pen_int) { |
| 240 | unsigned long reg; |
| 241 | |
| 242 | wm->pen_irq = atmel_wm97xx->gpio_irq; |
| 243 | |
| 244 | switch (wm->id) { |
| 245 | case WM9712_ID2: /* Fall through. */ |
| 246 | case WM9713_ID2: |
| 247 | /* |
| 248 | * Use GPIO 13 (PEN_DOWN) to assert GPIO line 3 |
| 249 | * (PENDOWN). |
| 250 | */ |
| 251 | wm97xx_config_gpio(wm, WM97XX_GPIO_13, WM97XX_GPIO_IN, |
| 252 | WM97XX_GPIO_POL_HIGH, |
| 253 | WM97XX_GPIO_STICKY, |
| 254 | WM97XX_GPIO_WAKE); |
| 255 | wm97xx_config_gpio(wm, WM97XX_GPIO_3, WM97XX_GPIO_OUT, |
| 256 | WM97XX_GPIO_POL_HIGH, |
| 257 | WM97XX_GPIO_NOTSTICKY, |
| 258 | WM97XX_GPIO_NOWAKE); |
| 259 | case WM9705_ID2: /* Fall through. */ |
| 260 | /* |
| 261 | * Enable touch data slot in AC97 controller channel B. |
| 262 | */ |
| 263 | reg = ac97c_readl(atmel_wm97xx, ICA); |
| 264 | reg &= ~AC97C_CH_MASK(wm->acc_slot); |
| 265 | reg |= AC97C_CH_ASSIGN(wm->acc_slot, B); |
| 266 | ac97c_writel(atmel_wm97xx, ICA, reg); |
| 267 | |
| 268 | /* |
| 269 | * Enable channel and interrupt for RXRDY and OVERRUN. |
| 270 | */ |
| 271 | ac97c_writel(atmel_wm97xx, CBMR, AC97C_CMR_CENA |
| 272 | | AC97C_CMR_CEM_BIG |
| 273 | | AC97C_CMR_SIZE_16 |
| 274 | | AC97C_OVRUN |
| 275 | | AC97C_RXRDY); |
| 276 | /* Dummy read to empty RXRHR. */ |
| 277 | ac97c_readl(atmel_wm97xx, CBRHR); |
| 278 | /* |
| 279 | * Enable interrupt for channel B in the AC97 |
| 280 | * controller. |
| 281 | */ |
| 282 | ac97c_writel(atmel_wm97xx, IER, AC97C_INT_CBEVT); |
| 283 | break; |
| 284 | default: |
| 285 | dev_err(&wm->touch_dev->dev, "pen down irq not " |
| 286 | "supported on this device\n"); |
| 287 | pen_int = 0; |
| 288 | break; |
| 289 | } |
| 290 | } |
| 291 | |
| 292 | return 0; |
| 293 | } |
| 294 | |
| 295 | static void atmel_wm97xx_acc_shutdown(struct wm97xx *wm) |
| 296 | { |
| 297 | if (pen_int) { |
| 298 | struct atmel_wm97xx *atmel_wm97xx = |
| 299 | platform_get_drvdata(wm->touch_dev); |
| 300 | unsigned long ica; |
| 301 | |
| 302 | switch (wm->id & 0xffff) { |
| 303 | case WM9705_ID2: /* Fall through. */ |
| 304 | case WM9712_ID2: /* Fall through. */ |
| 305 | case WM9713_ID2: |
| 306 | /* Disable slot and turn off channel B interrupts. */ |
| 307 | ica = ac97c_readl(atmel_wm97xx, ICA); |
| 308 | ica &= ~AC97C_CH_MASK(wm->acc_slot); |
| 309 | ac97c_writel(atmel_wm97xx, ICA, ica); |
| 310 | ac97c_writel(atmel_wm97xx, IDR, AC97C_INT_CBEVT); |
| 311 | ac97c_writel(atmel_wm97xx, CBMR, 0); |
| 312 | wm->pen_irq = 0; |
| 313 | break; |
| 314 | default: |
| 315 | dev_err(&wm->touch_dev->dev, "unknown codec\n"); |
| 316 | break; |
| 317 | } |
| 318 | } |
| 319 | } |
| 320 | |
| 321 | static void atmel_wm97xx_irq_enable(struct wm97xx *wm, int enable) |
| 322 | { |
| 323 | /* Intentionally left empty. */ |
| 324 | } |
| 325 | |
| 326 | static struct wm97xx_mach_ops atmel_mach_ops = { |
| 327 | .acc_enabled = 1, |
| 328 | .acc_pen_up = atmel_wm97xx_acc_pen_up, |
| 329 | .acc_startup = atmel_wm97xx_acc_startup, |
| 330 | .acc_shutdown = atmel_wm97xx_acc_shutdown, |
| 331 | .irq_enable = atmel_wm97xx_irq_enable, |
| 332 | .irq_gpio = WM97XX_GPIO_3, |
| 333 | }; |
| 334 | |
| 335 | static int __init atmel_wm97xx_probe(struct platform_device *pdev) |
| 336 | { |
| 337 | struct wm97xx *wm = platform_get_drvdata(pdev); |
| 338 | struct atmel_wm97xx *atmel_wm97xx; |
| 339 | int ret; |
| 340 | |
| 341 | atmel_wm97xx = kzalloc(sizeof(struct atmel_wm97xx), GFP_KERNEL); |
| 342 | if (!atmel_wm97xx) { |
| 343 | dev_dbg(&pdev->dev, "out of memory\n"); |
| 344 | return -ENOMEM; |
| 345 | } |
| 346 | |
| 347 | atmel_wm97xx->wm = wm; |
| 348 | atmel_wm97xx->regs = (void *)ATMEL_WM97XX_AC97C_IOMEM; |
| 349 | atmel_wm97xx->ac97c_irq = ATMEL_WM97XX_AC97C_IRQ; |
| 350 | atmel_wm97xx->gpio_pen = atmel_gpio_line; |
| 351 | atmel_wm97xx->gpio_irq = gpio_to_irq(atmel_wm97xx->gpio_pen); |
| 352 | |
| 353 | setup_timer(&atmel_wm97xx->pen_timer, atmel_wm97xx_pen_timer, |
| 354 | (unsigned long)wm); |
| 355 | |
| 356 | ret = request_irq(atmel_wm97xx->ac97c_irq, |
| 357 | atmel_wm97xx_channel_b_interrupt, |
| 358 | IRQF_SHARED, "atmel-wm97xx-ch-b", atmel_wm97xx); |
| 359 | if (ret) { |
| 360 | dev_dbg(&pdev->dev, "could not request ac97c irq\n"); |
| 361 | goto err; |
| 362 | } |
| 363 | |
| 364 | platform_set_drvdata(pdev, atmel_wm97xx); |
| 365 | |
| 366 | ret = wm97xx_register_mach_ops(wm, &atmel_mach_ops); |
| 367 | if (ret) |
| 368 | goto err_irq; |
| 369 | |
| 370 | return ret; |
| 371 | |
| 372 | err_irq: |
| 373 | free_irq(atmel_wm97xx->ac97c_irq, atmel_wm97xx); |
| 374 | err: |
| 375 | platform_set_drvdata(pdev, NULL); |
| 376 | kfree(atmel_wm97xx); |
| 377 | return ret; |
| 378 | } |
| 379 | |
| 380 | static int __exit atmel_wm97xx_remove(struct platform_device *pdev) |
| 381 | { |
| 382 | struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(pdev); |
| 383 | struct wm97xx *wm = atmel_wm97xx->wm; |
| 384 | |
| 385 | ac97c_writel(atmel_wm97xx, IDR, AC97C_INT_CBEVT); |
| 386 | free_irq(atmel_wm97xx->ac97c_irq, atmel_wm97xx); |
| 387 | del_timer_sync(&atmel_wm97xx->pen_timer); |
| 388 | wm97xx_unregister_mach_ops(wm); |
| 389 | platform_set_drvdata(pdev, NULL); |
| 390 | kfree(atmel_wm97xx); |
| 391 | |
| 392 | return 0; |
| 393 | } |
| 394 | |
| 395 | #ifdef CONFIG_PM |
| 396 | static int atmel_wm97xx_suspend(struct platform_device *pdev, pm_message_t msg) |
| 397 | { |
| 398 | struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(pdev); |
| 399 | |
| 400 | ac97c_writel(atmel_wm97xx, IDR, AC97C_INT_CBEVT); |
| 401 | disable_irq(atmel_wm97xx->gpio_irq); |
| 402 | del_timer_sync(&atmel_wm97xx->pen_timer); |
| 403 | |
| 404 | return 0; |
| 405 | } |
| 406 | |
| 407 | static int atmel_wm97xx_resume(struct platform_device *pdev) |
| 408 | { |
| 409 | struct atmel_wm97xx *atmel_wm97xx = platform_get_drvdata(pdev); |
| 410 | struct wm97xx *wm = atmel_wm97xx->wm; |
| 411 | |
| 412 | if (wm->input_dev->users) { |
| 413 | enable_irq(atmel_wm97xx->gpio_irq); |
| 414 | ac97c_writel(atmel_wm97xx, IER, AC97C_INT_CBEVT); |
| 415 | } |
| 416 | |
| 417 | return 0; |
| 418 | } |
| 419 | #else |
| 420 | #define atmel_wm97xx_suspend NULL |
| 421 | #define atmel_wm97xx_resume NULL |
| 422 | #endif |
| 423 | |
| 424 | static struct platform_driver atmel_wm97xx_driver = { |
| 425 | .remove = __exit_p(atmel_wm97xx_remove), |
| 426 | .driver = { |
| 427 | .name = "wm97xx-touch", |
| 428 | }, |
| 429 | .suspend = atmel_wm97xx_suspend, |
| 430 | .resume = atmel_wm97xx_resume, |
| 431 | }; |
Dmitry Torokhov | d3d2580 | 2012-01-10 15:08:01 -0800 | [diff] [blame] | 432 | |
| 433 | static int __init atmel_wm97xx_init(void) |
| 434 | { |
| 435 | return platform_driver_probe(&atmel_wm97xx_driver, atmel_wm97xx_probe); |
| 436 | } |
| 437 | module_init(atmel_wm97xx_init); |
| 438 | |
| 439 | static void __exit atmel_wm97xx_exit(void) |
| 440 | { |
| 441 | platform_driver_unregister(&atmel_wm97xx_driver); |
| 442 | } |
| 443 | module_exit(atmel_wm97xx_exit); |
Hans-Christian Egtvedt | 864fe73 | 2009-04-18 18:45:06 -0700 | [diff] [blame] | 444 | |
Hans-Christian Egtvedt | 7c40952 | 2011-06-29 00:13:26 -0700 | [diff] [blame] | 445 | MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>"); |
Hans-Christian Egtvedt | 864fe73 | 2009-04-18 18:45:06 -0700 | [diff] [blame] | 446 | MODULE_DESCRIPTION("wm97xx continuous touch driver for Atmel AT91 and AVR32"); |
| 447 | MODULE_LICENSE("GPL"); |