1 /* 2 * SPEAr Keyboard Driver 3 * Based on omap-keypad driver 4 * 5 * Copyright (C) 2010 ST Microelectronics 6 * Rajeev Kumar <rajeevkumar.linux@gmail.com> 7 * 8 * This file is licensed under the terms of the GNU General Public 9 * License version 2. This program is licensed "as is" without any 10 * warranty of any kind, whether express or implied. 11 */ 12 13 #include <linux/clk.h> 14 #include <linux/errno.h> 15 #include <linux/interrupt.h> 16 #include <linux/input.h> 17 #include <linux/io.h> 18 #include <linux/irq.h> 19 #include <linux/kernel.h> 20 #include <linux/module.h> 21 #include <linux/of.h> 22 #include <linux/platform_device.h> 23 #include <linux/pm_wakeup.h> 24 #include <linux/slab.h> 25 #include <linux/types.h> 26 #include <linux/platform_data/keyboard-spear.h> 27 28 /* Keyboard Registers */ 29 #define MODE_CTL_REG 0x00 30 #define STATUS_REG 0x0C 31 #define DATA_REG 0x10 32 #define INTR_MASK 0x54 33 34 /* Register Values */ 35 #define NUM_ROWS 16 36 #define NUM_COLS 16 37 #define MODE_CTL_PCLK_FREQ_SHIFT 9 38 #define MODE_CTL_PCLK_FREQ_MSK 0x7F 39 40 #define MODE_CTL_KEYBOARD (0x2 << 0) 41 #define MODE_CTL_SCAN_RATE_10 (0x0 << 2) 42 #define MODE_CTL_SCAN_RATE_20 (0x1 << 2) 43 #define MODE_CTL_SCAN_RATE_40 (0x2 << 2) 44 #define MODE_CTL_SCAN_RATE_80 (0x3 << 2) 45 #define MODE_CTL_KEYNUM_SHIFT 6 46 #define MODE_CTL_START_SCAN (0x1 << 8) 47 48 #define STATUS_DATA_AVAIL (0x1 << 1) 49 50 #define DATA_ROW_MASK 0xF0 51 #define DATA_COLUMN_MASK 0x0F 52 53 #define ROW_SHIFT 4 54 55 struct spear_kbd { 56 struct input_dev *input; 57 void __iomem *io_base; 58 struct clk *clk; 59 unsigned int irq; 60 unsigned int mode; 61 unsigned int suspended_rate; 62 unsigned short last_key; 63 unsigned short keycodes[NUM_ROWS * NUM_COLS]; 64 bool rep; 65 bool irq_wake_enabled; 66 u32 mode_ctl_reg; 67 }; 68 69 static irqreturn_t spear_kbd_interrupt(int irq, void *dev_id) 70 { 71 struct spear_kbd *kbd = dev_id; 72 struct input_dev *input = kbd->input; 73 unsigned int key; 74 u32 sts, val; 75 76 sts = readl_relaxed(kbd->io_base + STATUS_REG); 77 if (!(sts & STATUS_DATA_AVAIL)) 78 return IRQ_NONE; 79 80 if (kbd->last_key != KEY_RESERVED) { 81 input_report_key(input, kbd->last_key, 0); 82 kbd->last_key = KEY_RESERVED; 83 } 84 85 /* following reads active (row, col) pair */ 86 val = readl_relaxed(kbd->io_base + DATA_REG) & 87 (DATA_ROW_MASK | DATA_COLUMN_MASK); 88 key = kbd->keycodes[val]; 89 90 input_event(input, EV_MSC, MSC_SCAN, val); 91 input_report_key(input, key, 1); 92 input_sync(input); 93 94 kbd->last_key = key; 95 96 /* clear interrupt */ 97 writel_relaxed(0, kbd->io_base + STATUS_REG); 98 99 return IRQ_HANDLED; 100 } 101 102 static int spear_kbd_open(struct input_dev *dev) 103 { 104 struct spear_kbd *kbd = input_get_drvdata(dev); 105 int error; 106 u32 val; 107 108 kbd->last_key = KEY_RESERVED; 109 110 error = clk_enable(kbd->clk); 111 if (error) 112 return error; 113 114 /* keyboard rate to be programmed is input clock (in MHz) - 1 */ 115 val = clk_get_rate(kbd->clk) / 1000000 - 1; 116 val = (val & MODE_CTL_PCLK_FREQ_MSK) << MODE_CTL_PCLK_FREQ_SHIFT; 117 118 /* program keyboard */ 119 val = MODE_CTL_SCAN_RATE_80 | MODE_CTL_KEYBOARD | val | 120 (kbd->mode << MODE_CTL_KEYNUM_SHIFT); 121 writel_relaxed(val, kbd->io_base + MODE_CTL_REG); 122 writel_relaxed(1, kbd->io_base + STATUS_REG); 123 124 /* start key scan */ 125 val = readl_relaxed(kbd->io_base + MODE_CTL_REG); 126 val |= MODE_CTL_START_SCAN; 127 writel_relaxed(val, kbd->io_base + MODE_CTL_REG); 128 129 return 0; 130 } 131 132 static void spear_kbd_close(struct input_dev *dev) 133 { 134 struct spear_kbd *kbd = input_get_drvdata(dev); 135 u32 val; 136 137 /* stop key scan */ 138 val = readl_relaxed(kbd->io_base + MODE_CTL_REG); 139 val &= ~MODE_CTL_START_SCAN; 140 writel_relaxed(val, kbd->io_base + MODE_CTL_REG); 141 142 clk_disable(kbd->clk); 143 144 kbd->last_key = KEY_RESERVED; 145 } 146 147 #ifdef CONFIG_OF 148 static int spear_kbd_parse_dt(struct platform_device *pdev, 149 struct spear_kbd *kbd) 150 { 151 struct device_node *np = pdev->dev.of_node; 152 int error; 153 u32 val, suspended_rate; 154 155 if (!np) { 156 dev_err(&pdev->dev, "Missing DT data\n"); 157 return -EINVAL; 158 } 159 160 if (of_property_read_bool(np, "autorepeat")) 161 kbd->rep = true; 162 163 if (of_property_read_u32(np, "suspended_rate", &suspended_rate)) 164 kbd->suspended_rate = suspended_rate; 165 166 error = of_property_read_u32(np, "st,mode", &val); 167 if (error) { 168 dev_err(&pdev->dev, "DT: Invalid or missing mode\n"); 169 return error; 170 } 171 172 kbd->mode = val; 173 return 0; 174 } 175 #else 176 static inline int spear_kbd_parse_dt(struct platform_device *pdev, 177 struct spear_kbd *kbd) 178 { 179 return -ENOSYS; 180 } 181 #endif 182 183 static int spear_kbd_probe(struct platform_device *pdev) 184 { 185 struct kbd_platform_data *pdata = dev_get_platdata(&pdev->dev); 186 const struct matrix_keymap_data *keymap = pdata ? pdata->keymap : NULL; 187 struct spear_kbd *kbd; 188 struct input_dev *input_dev; 189 struct resource *res; 190 int irq; 191 int error; 192 193 irq = platform_get_irq(pdev, 0); 194 if (irq < 0) 195 return irq; 196 197 kbd = devm_kzalloc(&pdev->dev, sizeof(*kbd), GFP_KERNEL); 198 if (!kbd) { 199 dev_err(&pdev->dev, "not enough memory for driver data\n"); 200 return -ENOMEM; 201 } 202 203 input_dev = devm_input_allocate_device(&pdev->dev); 204 if (!input_dev) { 205 dev_err(&pdev->dev, "unable to allocate input device\n"); 206 return -ENOMEM; 207 } 208 209 kbd->input = input_dev; 210 kbd->irq = irq; 211 212 if (!pdata) { 213 error = spear_kbd_parse_dt(pdev, kbd); 214 if (error) 215 return error; 216 } else { 217 kbd->mode = pdata->mode; 218 kbd->rep = pdata->rep; 219 kbd->suspended_rate = pdata->suspended_rate; 220 } 221 222 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 223 kbd->io_base = devm_ioremap_resource(&pdev->dev, res); 224 if (IS_ERR(kbd->io_base)) 225 return PTR_ERR(kbd->io_base); 226 227 kbd->clk = devm_clk_get(&pdev->dev, NULL); 228 if (IS_ERR(kbd->clk)) 229 return PTR_ERR(kbd->clk); 230 231 input_dev->name = "Spear Keyboard"; 232 input_dev->phys = "keyboard/input0"; 233 input_dev->id.bustype = BUS_HOST; 234 input_dev->id.vendor = 0x0001; 235 input_dev->id.product = 0x0001; 236 input_dev->id.version = 0x0100; 237 input_dev->open = spear_kbd_open; 238 input_dev->close = spear_kbd_close; 239 240 error = matrix_keypad_build_keymap(keymap, NULL, NUM_ROWS, NUM_COLS, 241 kbd->keycodes, input_dev); 242 if (error) { 243 dev_err(&pdev->dev, "Failed to build keymap\n"); 244 return error; 245 } 246 247 if (kbd->rep) 248 __set_bit(EV_REP, input_dev->evbit); 249 input_set_capability(input_dev, EV_MSC, MSC_SCAN); 250 251 input_set_drvdata(input_dev, kbd); 252 253 error = devm_request_irq(&pdev->dev, irq, spear_kbd_interrupt, 0, 254 "keyboard", kbd); 255 if (error) { 256 dev_err(&pdev->dev, "request_irq failed\n"); 257 return error; 258 } 259 260 error = clk_prepare(kbd->clk); 261 if (error) 262 return error; 263 264 error = input_register_device(input_dev); 265 if (error) { 266 dev_err(&pdev->dev, "Unable to register keyboard device\n"); 267 clk_unprepare(kbd->clk); 268 return error; 269 } 270 271 device_init_wakeup(&pdev->dev, 1); 272 platform_set_drvdata(pdev, kbd); 273 274 return 0; 275 } 276 277 static int spear_kbd_remove(struct platform_device *pdev) 278 { 279 struct spear_kbd *kbd = platform_get_drvdata(pdev); 280 281 input_unregister_device(kbd->input); 282 clk_unprepare(kbd->clk); 283 284 return 0; 285 } 286 287 static int __maybe_unused spear_kbd_suspend(struct device *dev) 288 { 289 struct platform_device *pdev = to_platform_device(dev); 290 struct spear_kbd *kbd = platform_get_drvdata(pdev); 291 struct input_dev *input_dev = kbd->input; 292 unsigned int rate = 0, mode_ctl_reg, val; 293 294 mutex_lock(&input_dev->mutex); 295 296 /* explicitly enable clock as we may program device */ 297 clk_enable(kbd->clk); 298 299 mode_ctl_reg = readl_relaxed(kbd->io_base + MODE_CTL_REG); 300 301 if (device_may_wakeup(&pdev->dev)) { 302 if (!enable_irq_wake(kbd->irq)) 303 kbd->irq_wake_enabled = true; 304 305 /* 306 * reprogram the keyboard operating frequency as on some 307 * platform it may change during system suspended 308 */ 309 if (kbd->suspended_rate) 310 rate = kbd->suspended_rate / 1000000 - 1; 311 else 312 rate = clk_get_rate(kbd->clk) / 1000000 - 1; 313 314 val = mode_ctl_reg & 315 ~(MODE_CTL_PCLK_FREQ_MSK << MODE_CTL_PCLK_FREQ_SHIFT); 316 val |= (rate & MODE_CTL_PCLK_FREQ_MSK) 317 << MODE_CTL_PCLK_FREQ_SHIFT; 318 writel_relaxed(val, kbd->io_base + MODE_CTL_REG); 319 320 } else { 321 if (input_device_enabled(input_dev)) { 322 writel_relaxed(mode_ctl_reg & ~MODE_CTL_START_SCAN, 323 kbd->io_base + MODE_CTL_REG); 324 clk_disable(kbd->clk); 325 } 326 } 327 328 /* store current configuration */ 329 if (input_device_enabled(input_dev)) 330 kbd->mode_ctl_reg = mode_ctl_reg; 331 332 /* restore previous clk state */ 333 clk_disable(kbd->clk); 334 335 mutex_unlock(&input_dev->mutex); 336 337 return 0; 338 } 339 340 static int __maybe_unused spear_kbd_resume(struct device *dev) 341 { 342 struct platform_device *pdev = to_platform_device(dev); 343 struct spear_kbd *kbd = platform_get_drvdata(pdev); 344 struct input_dev *input_dev = kbd->input; 345 346 mutex_lock(&input_dev->mutex); 347 348 if (device_may_wakeup(&pdev->dev)) { 349 if (kbd->irq_wake_enabled) { 350 kbd->irq_wake_enabled = false; 351 disable_irq_wake(kbd->irq); 352 } 353 } else { 354 if (input_device_enabled(input_dev)) 355 clk_enable(kbd->clk); 356 } 357 358 /* restore current configuration */ 359 if (input_device_enabled(input_dev)) 360 writel_relaxed(kbd->mode_ctl_reg, kbd->io_base + MODE_CTL_REG); 361 362 mutex_unlock(&input_dev->mutex); 363 364 return 0; 365 } 366 367 static SIMPLE_DEV_PM_OPS(spear_kbd_pm_ops, spear_kbd_suspend, spear_kbd_resume); 368 369 #ifdef CONFIG_OF 370 static const struct of_device_id spear_kbd_id_table[] = { 371 { .compatible = "st,spear300-kbd" }, 372 {} 373 }; 374 MODULE_DEVICE_TABLE(of, spear_kbd_id_table); 375 #endif 376 377 static struct platform_driver spear_kbd_driver = { 378 .probe = spear_kbd_probe, 379 .remove = spear_kbd_remove, 380 .driver = { 381 .name = "keyboard", 382 .pm = &spear_kbd_pm_ops, 383 .of_match_table = of_match_ptr(spear_kbd_id_table), 384 }, 385 }; 386 module_platform_driver(spear_kbd_driver); 387 388 MODULE_AUTHOR("Rajeev Kumar"); 389 MODULE_DESCRIPTION("SPEAr Keyboard Driver"); 390 MODULE_LICENSE("GPL"); 391