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/slab.h> 24 #include <linux/types.h> 25 #include <linux/platform_data/keyboard-spear.h> 26 27 /* Keyboard Registers */ 28 #define MODE_CTL_REG 0x00 29 #define STATUS_REG 0x0C 30 #define DATA_REG 0x10 31 #define INTR_MASK 0x54 32 33 /* Register Values */ 34 #define NUM_ROWS 16 35 #define NUM_COLS 16 36 #define MODE_CTL_PCLK_FREQ_SHIFT 9 37 #define MODE_CTL_PCLK_FREQ_MSK 0x7F 38 39 #define MODE_CTL_KEYBOARD (0x2 << 0) 40 #define MODE_CTL_SCAN_RATE_10 (0x0 << 2) 41 #define MODE_CTL_SCAN_RATE_20 (0x1 << 2) 42 #define MODE_CTL_SCAN_RATE_40 (0x2 << 2) 43 #define MODE_CTL_SCAN_RATE_80 (0x3 << 2) 44 #define MODE_CTL_KEYNUM_SHIFT 6 45 #define MODE_CTL_START_SCAN (0x1 << 8) 46 47 #define STATUS_DATA_AVAIL (0x1 << 1) 48 49 #define DATA_ROW_MASK 0xF0 50 #define DATA_COLUMN_MASK 0x0F 51 52 #define ROW_SHIFT 4 53 54 struct spear_kbd { 55 struct input_dev *input; 56 void __iomem *io_base; 57 struct clk *clk; 58 unsigned int irq; 59 unsigned int mode; 60 unsigned int suspended_rate; 61 unsigned short last_key; 62 unsigned short keycodes[NUM_ROWS * NUM_COLS]; 63 bool rep; 64 bool irq_wake_enabled; 65 u32 mode_ctl_reg; 66 }; 67 68 static irqreturn_t spear_kbd_interrupt(int irq, void *dev_id) 69 { 70 struct spear_kbd *kbd = dev_id; 71 struct input_dev *input = kbd->input; 72 unsigned int key; 73 u32 sts, val; 74 75 sts = readl_relaxed(kbd->io_base + STATUS_REG); 76 if (!(sts & STATUS_DATA_AVAIL)) 77 return IRQ_NONE; 78 79 if (kbd->last_key != KEY_RESERVED) { 80 input_report_key(input, kbd->last_key, 0); 81 kbd->last_key = KEY_RESERVED; 82 } 83 84 /* following reads active (row, col) pair */ 85 val = readl_relaxed(kbd->io_base + DATA_REG) & 86 (DATA_ROW_MASK | DATA_COLUMN_MASK); 87 key = kbd->keycodes[val]; 88 89 input_event(input, EV_MSC, MSC_SCAN, val); 90 input_report_key(input, key, 1); 91 input_sync(input); 92 93 kbd->last_key = key; 94 95 /* clear interrupt */ 96 writel_relaxed(0, kbd->io_base + STATUS_REG); 97 98 return IRQ_HANDLED; 99 } 100 101 static int spear_kbd_open(struct input_dev *dev) 102 { 103 struct spear_kbd *kbd = input_get_drvdata(dev); 104 int error; 105 u32 val; 106 107 kbd->last_key = KEY_RESERVED; 108 109 error = clk_enable(kbd->clk); 110 if (error) 111 return error; 112 113 /* keyboard rate to be programmed is input clock (in MHz) - 1 */ 114 val = clk_get_rate(kbd->clk) / 1000000 - 1; 115 val = (val & MODE_CTL_PCLK_FREQ_MSK) << MODE_CTL_PCLK_FREQ_SHIFT; 116 117 /* program keyboard */ 118 val = MODE_CTL_SCAN_RATE_80 | MODE_CTL_KEYBOARD | val | 119 (kbd->mode << MODE_CTL_KEYNUM_SHIFT); 120 writel_relaxed(val, kbd->io_base + MODE_CTL_REG); 121 writel_relaxed(1, kbd->io_base + STATUS_REG); 122 123 /* start key scan */ 124 val = readl_relaxed(kbd->io_base + MODE_CTL_REG); 125 val |= MODE_CTL_START_SCAN; 126 writel_relaxed(val, kbd->io_base + MODE_CTL_REG); 127 128 return 0; 129 } 130 131 static void spear_kbd_close(struct input_dev *dev) 132 { 133 struct spear_kbd *kbd = input_get_drvdata(dev); 134 u32 val; 135 136 /* stop key scan */ 137 val = readl_relaxed(kbd->io_base + MODE_CTL_REG); 138 val &= ~MODE_CTL_START_SCAN; 139 writel_relaxed(val, kbd->io_base + MODE_CTL_REG); 140 141 clk_disable(kbd->clk); 142 143 kbd->last_key = KEY_RESERVED; 144 } 145 146 #ifdef CONFIG_OF 147 static int spear_kbd_parse_dt(struct platform_device *pdev, 148 struct spear_kbd *kbd) 149 { 150 struct device_node *np = pdev->dev.of_node; 151 int error; 152 u32 val, suspended_rate; 153 154 if (!np) { 155 dev_err(&pdev->dev, "Missing DT data\n"); 156 return -EINVAL; 157 } 158 159 if (of_property_read_bool(np, "autorepeat")) 160 kbd->rep = true; 161 162 if (of_property_read_u32(np, "suspended_rate", &suspended_rate)) 163 kbd->suspended_rate = suspended_rate; 164 165 error = of_property_read_u32(np, "st,mode", &val); 166 if (error) { 167 dev_err(&pdev->dev, "DT: Invalid or missing mode\n"); 168 return error; 169 } 170 171 kbd->mode = val; 172 return 0; 173 } 174 #else 175 static inline int spear_kbd_parse_dt(struct platform_device *pdev, 176 struct spear_kbd *kbd) 177 { 178 return -ENOSYS; 179 } 180 #endif 181 182 static int spear_kbd_probe(struct platform_device *pdev) 183 { 184 struct kbd_platform_data *pdata = dev_get_platdata(&pdev->dev); 185 const struct matrix_keymap_data *keymap = pdata ? pdata->keymap : NULL; 186 struct spear_kbd *kbd; 187 struct input_dev *input_dev; 188 int irq; 189 int error; 190 191 irq = platform_get_irq(pdev, 0); 192 if (irq < 0) 193 return irq; 194 195 kbd = devm_kzalloc(&pdev->dev, sizeof(*kbd), GFP_KERNEL); 196 if (!kbd) { 197 dev_err(&pdev->dev, "not enough memory for driver data\n"); 198 return -ENOMEM; 199 } 200 201 input_dev = devm_input_allocate_device(&pdev->dev); 202 if (!input_dev) { 203 dev_err(&pdev->dev, "unable to allocate input device\n"); 204 return -ENOMEM; 205 } 206 207 kbd->input = input_dev; 208 kbd->irq = irq; 209 210 if (!pdata) { 211 error = spear_kbd_parse_dt(pdev, kbd); 212 if (error) 213 return error; 214 } else { 215 kbd->mode = pdata->mode; 216 kbd->rep = pdata->rep; 217 kbd->suspended_rate = pdata->suspended_rate; 218 } 219 220 kbd->io_base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); 221 if (IS_ERR(kbd->io_base)) 222 return PTR_ERR(kbd->io_base); 223 224 kbd->clk = devm_clk_get_prepared(&pdev->dev, NULL); 225 if (IS_ERR(kbd->clk)) 226 return PTR_ERR(kbd->clk); 227 228 input_dev->name = "Spear Keyboard"; 229 input_dev->phys = "keyboard/input0"; 230 input_dev->id.bustype = BUS_HOST; 231 input_dev->id.vendor = 0x0001; 232 input_dev->id.product = 0x0001; 233 input_dev->id.version = 0x0100; 234 input_dev->open = spear_kbd_open; 235 input_dev->close = spear_kbd_close; 236 237 error = matrix_keypad_build_keymap(keymap, NULL, NUM_ROWS, NUM_COLS, 238 kbd->keycodes, input_dev); 239 if (error) { 240 dev_err(&pdev->dev, "Failed to build keymap\n"); 241 return error; 242 } 243 244 if (kbd->rep) 245 __set_bit(EV_REP, input_dev->evbit); 246 input_set_capability(input_dev, EV_MSC, MSC_SCAN); 247 248 input_set_drvdata(input_dev, kbd); 249 250 error = devm_request_irq(&pdev->dev, irq, spear_kbd_interrupt, 0, 251 "keyboard", kbd); 252 if (error) { 253 dev_err(&pdev->dev, "request_irq failed\n"); 254 return error; 255 } 256 257 error = input_register_device(input_dev); 258 if (error) { 259 dev_err(&pdev->dev, "Unable to register keyboard device\n"); 260 return error; 261 } 262 263 device_init_wakeup(&pdev->dev, 1); 264 platform_set_drvdata(pdev, kbd); 265 266 return 0; 267 } 268 269 static int spear_kbd_suspend(struct device *dev) 270 { 271 struct platform_device *pdev = to_platform_device(dev); 272 struct spear_kbd *kbd = platform_get_drvdata(pdev); 273 struct input_dev *input_dev = kbd->input; 274 unsigned int rate = 0, mode_ctl_reg, val; 275 276 guard(mutex)(&input_dev->mutex); 277 278 /* explicitly enable clock as we may program device */ 279 clk_enable(kbd->clk); 280 281 mode_ctl_reg = readl_relaxed(kbd->io_base + MODE_CTL_REG); 282 283 if (device_may_wakeup(&pdev->dev)) { 284 if (!enable_irq_wake(kbd->irq)) 285 kbd->irq_wake_enabled = true; 286 287 /* 288 * reprogram the keyboard operating frequency as on some 289 * platform it may change during system suspended 290 */ 291 if (kbd->suspended_rate) 292 rate = kbd->suspended_rate / 1000000 - 1; 293 else 294 rate = clk_get_rate(kbd->clk) / 1000000 - 1; 295 296 val = mode_ctl_reg & 297 ~(MODE_CTL_PCLK_FREQ_MSK << MODE_CTL_PCLK_FREQ_SHIFT); 298 val |= (rate & MODE_CTL_PCLK_FREQ_MSK) 299 << MODE_CTL_PCLK_FREQ_SHIFT; 300 writel_relaxed(val, kbd->io_base + MODE_CTL_REG); 301 302 } else { 303 if (input_device_enabled(input_dev)) { 304 writel_relaxed(mode_ctl_reg & ~MODE_CTL_START_SCAN, 305 kbd->io_base + MODE_CTL_REG); 306 clk_disable(kbd->clk); 307 } 308 } 309 310 /* store current configuration */ 311 if (input_device_enabled(input_dev)) 312 kbd->mode_ctl_reg = mode_ctl_reg; 313 314 /* restore previous clk state */ 315 clk_disable(kbd->clk); 316 317 return 0; 318 } 319 320 static int spear_kbd_resume(struct device *dev) 321 { 322 struct platform_device *pdev = to_platform_device(dev); 323 struct spear_kbd *kbd = platform_get_drvdata(pdev); 324 struct input_dev *input_dev = kbd->input; 325 326 guard(mutex)(&input_dev->mutex); 327 328 if (device_may_wakeup(&pdev->dev)) { 329 if (kbd->irq_wake_enabled) { 330 kbd->irq_wake_enabled = false; 331 disable_irq_wake(kbd->irq); 332 } 333 } else { 334 if (input_device_enabled(input_dev)) 335 clk_enable(kbd->clk); 336 } 337 338 /* restore current configuration */ 339 if (input_device_enabled(input_dev)) 340 writel_relaxed(kbd->mode_ctl_reg, kbd->io_base + MODE_CTL_REG); 341 342 return 0; 343 } 344 345 static DEFINE_SIMPLE_DEV_PM_OPS(spear_kbd_pm_ops, 346 spear_kbd_suspend, spear_kbd_resume); 347 348 #ifdef CONFIG_OF 349 static const struct of_device_id spear_kbd_id_table[] = { 350 { .compatible = "st,spear300-kbd" }, 351 {} 352 }; 353 MODULE_DEVICE_TABLE(of, spear_kbd_id_table); 354 #endif 355 356 static struct platform_driver spear_kbd_driver = { 357 .probe = spear_kbd_probe, 358 .driver = { 359 .name = "keyboard", 360 .pm = pm_sleep_ptr(&spear_kbd_pm_ops), 361 .of_match_table = of_match_ptr(spear_kbd_id_table), 362 }, 363 }; 364 module_platform_driver(spear_kbd_driver); 365 366 MODULE_AUTHOR("Rajeev Kumar"); 367 MODULE_DESCRIPTION("SPEAr Keyboard Driver"); 368 MODULE_LICENSE("GPL"); 369