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 dev_err(&pdev->dev, "not able to get irq for the device\n"); 196 return irq; 197 } 198 199 kbd = devm_kzalloc(&pdev->dev, sizeof(*kbd), GFP_KERNEL); 200 if (!kbd) { 201 dev_err(&pdev->dev, "not enough memory for driver data\n"); 202 return -ENOMEM; 203 } 204 205 input_dev = devm_input_allocate_device(&pdev->dev); 206 if (!input_dev) { 207 dev_err(&pdev->dev, "unable to allocate input device\n"); 208 return -ENOMEM; 209 } 210 211 kbd->input = input_dev; 212 kbd->irq = irq; 213 214 if (!pdata) { 215 error = spear_kbd_parse_dt(pdev, kbd); 216 if (error) 217 return error; 218 } else { 219 kbd->mode = pdata->mode; 220 kbd->rep = pdata->rep; 221 kbd->suspended_rate = pdata->suspended_rate; 222 } 223 224 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 225 kbd->io_base = devm_ioremap_resource(&pdev->dev, res); 226 if (IS_ERR(kbd->io_base)) 227 return PTR_ERR(kbd->io_base); 228 229 kbd->clk = devm_clk_get(&pdev->dev, NULL); 230 if (IS_ERR(kbd->clk)) 231 return PTR_ERR(kbd->clk); 232 233 input_dev->name = "Spear Keyboard"; 234 input_dev->phys = "keyboard/input0"; 235 input_dev->id.bustype = BUS_HOST; 236 input_dev->id.vendor = 0x0001; 237 input_dev->id.product = 0x0001; 238 input_dev->id.version = 0x0100; 239 input_dev->open = spear_kbd_open; 240 input_dev->close = spear_kbd_close; 241 242 error = matrix_keypad_build_keymap(keymap, NULL, NUM_ROWS, NUM_COLS, 243 kbd->keycodes, input_dev); 244 if (error) { 245 dev_err(&pdev->dev, "Failed to build keymap\n"); 246 return error; 247 } 248 249 if (kbd->rep) 250 __set_bit(EV_REP, input_dev->evbit); 251 input_set_capability(input_dev, EV_MSC, MSC_SCAN); 252 253 input_set_drvdata(input_dev, kbd); 254 255 error = devm_request_irq(&pdev->dev, irq, spear_kbd_interrupt, 0, 256 "keyboard", kbd); 257 if (error) { 258 dev_err(&pdev->dev, "request_irq failed\n"); 259 return error; 260 } 261 262 error = clk_prepare(kbd->clk); 263 if (error) 264 return error; 265 266 error = input_register_device(input_dev); 267 if (error) { 268 dev_err(&pdev->dev, "Unable to register keyboard device\n"); 269 clk_unprepare(kbd->clk); 270 return error; 271 } 272 273 device_init_wakeup(&pdev->dev, 1); 274 platform_set_drvdata(pdev, kbd); 275 276 return 0; 277 } 278 279 static int spear_kbd_remove(struct platform_device *pdev) 280 { 281 struct spear_kbd *kbd = platform_get_drvdata(pdev); 282 283 input_unregister_device(kbd->input); 284 clk_unprepare(kbd->clk); 285 286 return 0; 287 } 288 289 static int __maybe_unused spear_kbd_suspend(struct device *dev) 290 { 291 struct platform_device *pdev = to_platform_device(dev); 292 struct spear_kbd *kbd = platform_get_drvdata(pdev); 293 struct input_dev *input_dev = kbd->input; 294 unsigned int rate = 0, mode_ctl_reg, val; 295 296 mutex_lock(&input_dev->mutex); 297 298 /* explicitly enable clock as we may program device */ 299 clk_enable(kbd->clk); 300 301 mode_ctl_reg = readl_relaxed(kbd->io_base + MODE_CTL_REG); 302 303 if (device_may_wakeup(&pdev->dev)) { 304 if (!enable_irq_wake(kbd->irq)) 305 kbd->irq_wake_enabled = true; 306 307 /* 308 * reprogram the keyboard operating frequency as on some 309 * platform it may change during system suspended 310 */ 311 if (kbd->suspended_rate) 312 rate = kbd->suspended_rate / 1000000 - 1; 313 else 314 rate = clk_get_rate(kbd->clk) / 1000000 - 1; 315 316 val = mode_ctl_reg & 317 ~(MODE_CTL_PCLK_FREQ_MSK << MODE_CTL_PCLK_FREQ_SHIFT); 318 val |= (rate & MODE_CTL_PCLK_FREQ_MSK) 319 << MODE_CTL_PCLK_FREQ_SHIFT; 320 writel_relaxed(val, kbd->io_base + MODE_CTL_REG); 321 322 } else { 323 if (input_dev->users) { 324 writel_relaxed(mode_ctl_reg & ~MODE_CTL_START_SCAN, 325 kbd->io_base + MODE_CTL_REG); 326 clk_disable(kbd->clk); 327 } 328 } 329 330 /* store current configuration */ 331 if (input_dev->users) 332 kbd->mode_ctl_reg = mode_ctl_reg; 333 334 /* restore previous clk state */ 335 clk_disable(kbd->clk); 336 337 mutex_unlock(&input_dev->mutex); 338 339 return 0; 340 } 341 342 static int __maybe_unused spear_kbd_resume(struct device *dev) 343 { 344 struct platform_device *pdev = to_platform_device(dev); 345 struct spear_kbd *kbd = platform_get_drvdata(pdev); 346 struct input_dev *input_dev = kbd->input; 347 348 mutex_lock(&input_dev->mutex); 349 350 if (device_may_wakeup(&pdev->dev)) { 351 if (kbd->irq_wake_enabled) { 352 kbd->irq_wake_enabled = false; 353 disable_irq_wake(kbd->irq); 354 } 355 } else { 356 if (input_dev->users) 357 clk_enable(kbd->clk); 358 } 359 360 /* restore current configuration */ 361 if (input_dev->users) 362 writel_relaxed(kbd->mode_ctl_reg, kbd->io_base + MODE_CTL_REG); 363 364 mutex_unlock(&input_dev->mutex); 365 366 return 0; 367 } 368 369 static SIMPLE_DEV_PM_OPS(spear_kbd_pm_ops, spear_kbd_suspend, spear_kbd_resume); 370 371 #ifdef CONFIG_OF 372 static const struct of_device_id spear_kbd_id_table[] = { 373 { .compatible = "st,spear300-kbd" }, 374 {} 375 }; 376 MODULE_DEVICE_TABLE(of, spear_kbd_id_table); 377 #endif 378 379 static struct platform_driver spear_kbd_driver = { 380 .probe = spear_kbd_probe, 381 .remove = spear_kbd_remove, 382 .driver = { 383 .name = "keyboard", 384 .pm = &spear_kbd_pm_ops, 385 .of_match_table = of_match_ptr(spear_kbd_id_table), 386 }, 387 }; 388 module_platform_driver(spear_kbd_driver); 389 390 MODULE_AUTHOR("Rajeev Kumar"); 391 MODULE_DESCRIPTION("SPEAr Keyboard Driver"); 392 MODULE_LICENSE("GPL"); 393