Roland Stigge | 69690be | 2012-07-13 00:08:34 -0700 | [diff] [blame] | 1 | /* |
| 2 | * NXP LPC32xx SoC Key Scan Interface |
| 3 | * |
| 4 | * Authors: |
| 5 | * Kevin Wells <kevin.wells@nxp.com> |
| 6 | * Roland Stigge <stigge@antcom.de> |
| 7 | * |
| 8 | * Copyright (C) 2010 NXP Semiconductors |
| 9 | * Copyright (C) 2012 Roland Stigge |
| 10 | * |
| 11 | * This program is free software; you can redistribute it and/or modify |
| 12 | * it under the terms of the GNU General Public License as published by |
| 13 | * the Free Software Foundation; either version 2 of the License, or |
| 14 | * (at your option) any later version. |
| 15 | * |
| 16 | * This program is distributed in the hope that it will be useful, |
| 17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 19 | * GNU General Public License for more details. |
| 20 | * |
| 21 | * |
| 22 | * This controller supports square key matrices from 1x1 up to 8x8 |
| 23 | */ |
| 24 | |
| 25 | #include <linux/module.h> |
| 26 | #include <linux/interrupt.h> |
| 27 | #include <linux/slab.h> |
| 28 | #include <linux/irq.h> |
| 29 | #include <linux/pm.h> |
| 30 | #include <linux/platform_device.h> |
| 31 | #include <linux/input.h> |
| 32 | #include <linux/clk.h> |
| 33 | #include <linux/io.h> |
| 34 | #include <linux/of.h> |
| 35 | #include <linux/input/matrix_keypad.h> |
| 36 | |
| 37 | #define DRV_NAME "lpc32xx_keys" |
| 38 | |
| 39 | /* |
| 40 | * Key scanner register offsets |
| 41 | */ |
| 42 | #define LPC32XX_KS_DEB(x) ((x) + 0x00) |
| 43 | #define LPC32XX_KS_STATE_COND(x) ((x) + 0x04) |
| 44 | #define LPC32XX_KS_IRQ(x) ((x) + 0x08) |
| 45 | #define LPC32XX_KS_SCAN_CTL(x) ((x) + 0x0C) |
| 46 | #define LPC32XX_KS_FAST_TST(x) ((x) + 0x10) |
| 47 | #define LPC32XX_KS_MATRIX_DIM(x) ((x) + 0x14) /* 1..8 */ |
| 48 | #define LPC32XX_KS_DATA(x, y) ((x) + 0x40 + ((y) << 2)) |
| 49 | |
| 50 | #define LPC32XX_KSCAN_DEB_NUM_DEB_PASS(n) ((n) & 0xFF) |
| 51 | |
| 52 | #define LPC32XX_KSCAN_SCOND_IN_IDLE 0x0 |
| 53 | #define LPC32XX_KSCAN_SCOND_IN_SCANONCE 0x1 |
| 54 | #define LPC32XX_KSCAN_SCOND_IN_IRQGEN 0x2 |
| 55 | #define LPC32XX_KSCAN_SCOND_IN_SCAN_MATRIX 0x3 |
| 56 | |
| 57 | #define LPC32XX_KSCAN_IRQ_PENDING_CLR 0x1 |
| 58 | |
| 59 | #define LPC32XX_KSCAN_SCTRL_SCAN_DELAY(n) ((n) & 0xFF) |
| 60 | |
| 61 | #define LPC32XX_KSCAN_FTST_FORCESCANONCE 0x1 |
| 62 | #define LPC32XX_KSCAN_FTST_USE32K_CLK 0x2 |
| 63 | |
| 64 | #define LPC32XX_KSCAN_MSEL_SELECT(n) ((n) & 0xF) |
| 65 | |
| 66 | struct lpc32xx_kscan_drv { |
| 67 | struct input_dev *input; |
| 68 | struct clk *clk; |
| 69 | struct resource *iores; |
| 70 | void __iomem *kscan_base; |
| 71 | unsigned int irq; |
| 72 | |
| 73 | u32 matrix_sz; /* Size of matrix in XxY, ie. 3 = 3x3 */ |
| 74 | u32 deb_clks; /* Debounce clocks (based on 32KHz clock) */ |
| 75 | u32 scan_delay; /* Scan delay (based on 32KHz clock) */ |
| 76 | |
| 77 | unsigned short *keymap; /* Pointer to key map for the scan matrix */ |
| 78 | unsigned int row_shift; |
| 79 | |
| 80 | u8 lastkeystates[8]; |
| 81 | }; |
| 82 | |
| 83 | static void lpc32xx_mod_states(struct lpc32xx_kscan_drv *kscandat, int col) |
| 84 | { |
| 85 | struct input_dev *input = kscandat->input; |
| 86 | unsigned row, changed, scancode, keycode; |
| 87 | u8 key; |
| 88 | |
| 89 | key = readl(LPC32XX_KS_DATA(kscandat->kscan_base, col)); |
| 90 | changed = key ^ kscandat->lastkeystates[col]; |
| 91 | kscandat->lastkeystates[col] = key; |
| 92 | |
| 93 | for (row = 0; changed; row++, changed >>= 1) { |
| 94 | if (changed & 1) { |
| 95 | /* Key state changed, signal an event */ |
| 96 | scancode = MATRIX_SCAN_CODE(row, col, |
| 97 | kscandat->row_shift); |
| 98 | keycode = kscandat->keymap[scancode]; |
| 99 | input_event(input, EV_MSC, MSC_SCAN, scancode); |
| 100 | input_report_key(input, keycode, key & (1 << row)); |
| 101 | } |
| 102 | } |
| 103 | } |
| 104 | |
| 105 | static irqreturn_t lpc32xx_kscan_irq(int irq, void *dev_id) |
| 106 | { |
| 107 | struct lpc32xx_kscan_drv *kscandat = dev_id; |
| 108 | int i; |
| 109 | |
| 110 | for (i = 0; i < kscandat->matrix_sz; i++) |
| 111 | lpc32xx_mod_states(kscandat, i); |
| 112 | |
| 113 | writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base)); |
| 114 | |
| 115 | input_sync(kscandat->input); |
| 116 | |
| 117 | return IRQ_HANDLED; |
| 118 | } |
| 119 | |
| 120 | static int lpc32xx_kscan_open(struct input_dev *dev) |
| 121 | { |
| 122 | struct lpc32xx_kscan_drv *kscandat = input_get_drvdata(dev); |
| 123 | int error; |
| 124 | |
| 125 | error = clk_prepare_enable(kscandat->clk); |
| 126 | if (error) |
| 127 | return error; |
| 128 | |
| 129 | writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base)); |
| 130 | |
| 131 | return 0; |
| 132 | } |
| 133 | |
| 134 | static void lpc32xx_kscan_close(struct input_dev *dev) |
| 135 | { |
| 136 | struct lpc32xx_kscan_drv *kscandat = input_get_drvdata(dev); |
| 137 | |
| 138 | writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base)); |
| 139 | clk_disable_unprepare(kscandat->clk); |
| 140 | } |
| 141 | |
| 142 | static int __devinit lpc32xx_parse_dt(struct device *dev, |
| 143 | struct lpc32xx_kscan_drv *kscandat) |
| 144 | { |
| 145 | struct device_node *np = dev->of_node; |
| 146 | u32 rows = 0, columns = 0; |
| 147 | |
| 148 | of_property_read_u32(np, "keypad,num-rows", &rows); |
| 149 | of_property_read_u32(np, "keypad,num-columns", &columns); |
| 150 | if (!rows || rows != columns) { |
| 151 | dev_err(dev, |
| 152 | "rows and columns must be specified and be equal!\n"); |
| 153 | return -EINVAL; |
| 154 | } |
| 155 | |
| 156 | kscandat->matrix_sz = rows; |
| 157 | kscandat->row_shift = get_count_order(columns); |
| 158 | |
| 159 | of_property_read_u32(np, "nxp,debounce-delay-ms", &kscandat->deb_clks); |
| 160 | of_property_read_u32(np, "nxp,scan-delay-ms", &kscandat->scan_delay); |
| 161 | if (!kscandat->deb_clks || !kscandat->scan_delay) { |
| 162 | dev_err(dev, "debounce or scan delay not specified\n"); |
| 163 | return -EINVAL; |
| 164 | } |
| 165 | |
| 166 | return 0; |
| 167 | } |
| 168 | |
| 169 | static int __devinit lpc32xx_kscan_probe(struct platform_device *pdev) |
| 170 | { |
| 171 | struct lpc32xx_kscan_drv *kscandat; |
| 172 | struct input_dev *input; |
| 173 | struct resource *res; |
| 174 | size_t keymap_size; |
| 175 | int error; |
| 176 | int irq; |
| 177 | |
| 178 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| 179 | if (!res) { |
| 180 | dev_err(&pdev->dev, "failed to get platform I/O memory\n"); |
| 181 | return -EINVAL; |
| 182 | } |
| 183 | |
| 184 | irq = platform_get_irq(pdev, 0); |
| 185 | if (irq < 0 || irq >= NR_IRQS) { |
| 186 | dev_err(&pdev->dev, "failed to get platform irq\n"); |
| 187 | return -EINVAL; |
| 188 | } |
| 189 | |
| 190 | kscandat = kzalloc(sizeof(struct lpc32xx_kscan_drv), GFP_KERNEL); |
| 191 | if (!kscandat) { |
| 192 | dev_err(&pdev->dev, "failed to allocate memory\n"); |
| 193 | return -ENOMEM; |
| 194 | } |
| 195 | |
| 196 | error = lpc32xx_parse_dt(&pdev->dev, kscandat); |
| 197 | if (error) { |
| 198 | dev_err(&pdev->dev, "failed to parse device tree\n"); |
| 199 | goto err_free_mem; |
| 200 | } |
| 201 | |
| 202 | keymap_size = sizeof(kscandat->keymap[0]) * |
| 203 | (kscandat->matrix_sz << kscandat->row_shift); |
| 204 | kscandat->keymap = kzalloc(keymap_size, GFP_KERNEL); |
| 205 | if (!kscandat->keymap) { |
| 206 | dev_err(&pdev->dev, "could not allocate memory for keymap\n"); |
| 207 | error = -ENOMEM; |
| 208 | goto err_free_mem; |
| 209 | } |
| 210 | |
| 211 | kscandat->input = input = input_allocate_device(); |
| 212 | if (!input) { |
| 213 | dev_err(&pdev->dev, "failed to allocate input device\n"); |
| 214 | error = -ENOMEM; |
| 215 | goto err_free_keymap; |
| 216 | } |
| 217 | |
| 218 | /* Setup key input */ |
| 219 | input->name = pdev->name; |
| 220 | input->phys = "lpc32xx/input0"; |
| 221 | input->id.vendor = 0x0001; |
| 222 | input->id.product = 0x0001; |
| 223 | input->id.version = 0x0100; |
| 224 | input->open = lpc32xx_kscan_open; |
| 225 | input->close = lpc32xx_kscan_close; |
| 226 | input->dev.parent = &pdev->dev; |
| 227 | |
| 228 | input_set_capability(input, EV_MSC, MSC_SCAN); |
| 229 | |
| 230 | error = matrix_keypad_build_keymap(NULL, NULL, |
| 231 | kscandat->matrix_sz, |
| 232 | kscandat->matrix_sz, |
| 233 | kscandat->keymap, kscandat->input); |
| 234 | if (error) { |
| 235 | dev_err(&pdev->dev, "failed to build keymap\n"); |
| 236 | goto err_free_input; |
| 237 | } |
| 238 | |
| 239 | input_set_drvdata(kscandat->input, kscandat); |
| 240 | |
| 241 | kscandat->iores = request_mem_region(res->start, resource_size(res), |
| 242 | pdev->name); |
| 243 | if (!kscandat->iores) { |
| 244 | dev_err(&pdev->dev, "failed to request I/O memory\n"); |
| 245 | error = -EBUSY; |
| 246 | goto err_free_input; |
| 247 | } |
| 248 | |
| 249 | kscandat->kscan_base = ioremap(kscandat->iores->start, |
| 250 | resource_size(kscandat->iores)); |
| 251 | if (!kscandat->kscan_base) { |
| 252 | dev_err(&pdev->dev, "failed to remap I/O memory\n"); |
| 253 | error = -EBUSY; |
| 254 | goto err_release_memregion; |
| 255 | } |
| 256 | |
| 257 | /* Get the key scanner clock */ |
| 258 | kscandat->clk = clk_get(&pdev->dev, NULL); |
| 259 | if (IS_ERR(kscandat->clk)) { |
| 260 | dev_err(&pdev->dev, "failed to get clock\n"); |
| 261 | error = PTR_ERR(kscandat->clk); |
| 262 | goto err_unmap; |
| 263 | } |
| 264 | |
| 265 | /* Configure the key scanner */ |
| 266 | error = clk_prepare_enable(kscandat->clk); |
| 267 | if (error) |
| 268 | goto err_clk_put; |
| 269 | |
| 270 | writel(kscandat->deb_clks, LPC32XX_KS_DEB(kscandat->kscan_base)); |
| 271 | writel(kscandat->scan_delay, LPC32XX_KS_SCAN_CTL(kscandat->kscan_base)); |
| 272 | writel(LPC32XX_KSCAN_FTST_USE32K_CLK, |
| 273 | LPC32XX_KS_FAST_TST(kscandat->kscan_base)); |
| 274 | writel(kscandat->matrix_sz, |
| 275 | LPC32XX_KS_MATRIX_DIM(kscandat->kscan_base)); |
| 276 | writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base)); |
| 277 | clk_disable_unprepare(kscandat->clk); |
| 278 | |
| 279 | error = request_irq(irq, lpc32xx_kscan_irq, 0, pdev->name, kscandat); |
| 280 | if (error) { |
| 281 | dev_err(&pdev->dev, "failed to request irq\n"); |
| 282 | goto err_clk_put; |
| 283 | } |
| 284 | |
| 285 | error = input_register_device(kscandat->input); |
| 286 | if (error) { |
| 287 | dev_err(&pdev->dev, "failed to register input device\n"); |
| 288 | goto err_free_irq; |
| 289 | } |
| 290 | |
| 291 | platform_set_drvdata(pdev, kscandat); |
| 292 | return 0; |
| 293 | |
| 294 | err_free_irq: |
| 295 | free_irq(irq, kscandat); |
| 296 | err_clk_put: |
| 297 | clk_put(kscandat->clk); |
| 298 | err_unmap: |
| 299 | iounmap(kscandat->kscan_base); |
| 300 | err_release_memregion: |
| 301 | release_mem_region(kscandat->iores->start, |
| 302 | resource_size(kscandat->iores)); |
| 303 | err_free_input: |
| 304 | input_free_device(kscandat->input); |
| 305 | err_free_keymap: |
| 306 | kfree(kscandat->keymap); |
| 307 | err_free_mem: |
| 308 | kfree(kscandat); |
| 309 | |
| 310 | return error; |
| 311 | } |
| 312 | |
| 313 | static int __devexit lpc32xx_kscan_remove(struct platform_device *pdev) |
| 314 | { |
| 315 | struct lpc32xx_kscan_drv *kscandat = platform_get_drvdata(pdev); |
| 316 | |
| 317 | free_irq(platform_get_irq(pdev, 0), kscandat); |
| 318 | clk_put(kscandat->clk); |
| 319 | iounmap(kscandat->kscan_base); |
| 320 | release_mem_region(kscandat->iores->start, |
| 321 | resource_size(kscandat->iores)); |
| 322 | input_unregister_device(kscandat->input); |
| 323 | kfree(kscandat->keymap); |
| 324 | kfree(kscandat); |
| 325 | |
| 326 | return 0; |
| 327 | } |
| 328 | |
| 329 | #ifdef CONFIG_PM_SLEEP |
| 330 | static int lpc32xx_kscan_suspend(struct device *dev) |
| 331 | { |
| 332 | struct platform_device *pdev = to_platform_device(dev); |
| 333 | struct lpc32xx_kscan_drv *kscandat = platform_get_drvdata(pdev); |
| 334 | struct input_dev *input = kscandat->input; |
| 335 | |
| 336 | mutex_lock(&input->mutex); |
| 337 | |
| 338 | if (input->users) { |
| 339 | /* Clear IRQ and disable clock */ |
| 340 | writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base)); |
| 341 | clk_disable_unprepare(kscandat->clk); |
| 342 | } |
| 343 | |
| 344 | mutex_unlock(&input->mutex); |
| 345 | return 0; |
| 346 | } |
| 347 | |
| 348 | static int lpc32xx_kscan_resume(struct device *dev) |
| 349 | { |
| 350 | struct platform_device *pdev = to_platform_device(dev); |
| 351 | struct lpc32xx_kscan_drv *kscandat = platform_get_drvdata(pdev); |
| 352 | struct input_dev *input = kscandat->input; |
| 353 | int retval = 0; |
| 354 | |
| 355 | mutex_lock(&input->mutex); |
| 356 | |
| 357 | if (input->users) { |
| 358 | /* Enable clock and clear IRQ */ |
| 359 | retval = clk_prepare_enable(kscandat->clk); |
| 360 | if (retval == 0) |
| 361 | writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base)); |
| 362 | } |
| 363 | |
| 364 | mutex_unlock(&input->mutex); |
| 365 | return retval; |
| 366 | } |
| 367 | #endif |
| 368 | |
| 369 | static SIMPLE_DEV_PM_OPS(lpc32xx_kscan_pm_ops, lpc32xx_kscan_suspend, |
| 370 | lpc32xx_kscan_resume); |
| 371 | |
| 372 | static const struct of_device_id lpc32xx_kscan_match[] = { |
| 373 | { .compatible = "nxp,lpc3220-key" }, |
| 374 | {}, |
| 375 | }; |
| 376 | MODULE_DEVICE_TABLE(of, lpc32xx_kscan_match); |
| 377 | |
| 378 | static struct platform_driver lpc32xx_kscan_driver = { |
| 379 | .probe = lpc32xx_kscan_probe, |
Bill Pemberton | 1cb0aa8 | 2012-11-23 21:27:39 -0800 | [diff] [blame^] | 380 | .remove = lpc32xx_kscan_remove, |
Roland Stigge | 69690be | 2012-07-13 00:08:34 -0700 | [diff] [blame] | 381 | .driver = { |
| 382 | .name = DRV_NAME, |
| 383 | .owner = THIS_MODULE, |
| 384 | .pm = &lpc32xx_kscan_pm_ops, |
| 385 | .of_match_table = of_match_ptr(lpc32xx_kscan_match), |
| 386 | } |
| 387 | }; |
| 388 | |
| 389 | module_platform_driver(lpc32xx_kscan_driver); |
| 390 | |
| 391 | MODULE_LICENSE("GPL"); |
| 392 | MODULE_AUTHOR("Kevin Wells <kevin.wells@nxp.com>"); |
| 393 | MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>"); |
| 394 | MODULE_DESCRIPTION("Key scanner driver for LPC32XX devices"); |