| 1 | /* |
| 2 | * arch/ubicom32/mach-common/ubicom32input.c |
| 3 | * Ubicom32 Input driver |
| 4 | * |
| 5 | * based on gpio-keys |
| 6 | * |
| 7 | * (C) Copyright 2009, Ubicom, Inc. |
| 8 | * |
| 9 | * This file is part of the Ubicom32 Linux Kernel Port. |
| 10 | * |
| 11 | * The Ubicom32 Linux Kernel Port is free software: you can redistribute |
| 12 | * it and/or modify it under the terms of the GNU General Public License |
| 13 | * as published by the Free Software Foundation, either version 2 of the |
| 14 | * License, or (at your option) any later version. |
| 15 | * |
| 16 | * The Ubicom32 Linux Kernel Port is distributed in the hope that it |
| 17 | * will be useful, but WITHOUT ANY WARRANTY; without even the implied |
| 18 | * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See |
| 19 | * the GNU General Public License for more details. |
| 20 | * |
| 21 | * You should have received a copy of the GNU General Public License |
| 22 | * along with the Ubicom32 Linux Kernel Port. If not, |
| 23 | * see <http://www.gnu.org/licenses/>. |
| 24 | * |
| 25 | * Ubicom32 implementation derived from (with many thanks): |
| 26 | * arch/m68knommu |
| 27 | * arch/blackfin |
| 28 | * arch/parisc |
| 29 | * |
| 30 | * |
| 31 | * TODO: add groups for inputs which can be sampled together (i.e. I2C) |
| 32 | */ |
| 33 | |
| 34 | #include <linux/kernel.h> |
| 35 | #include <linux/module.h> |
| 36 | #include <linux/platform_device.h> |
| 37 | #include <linux/input.h> |
| 38 | #include <linux/input-polldev.h> |
| 39 | #include <linux/delay.h> |
| 40 | #include <linux/gpio.h> |
| 41 | |
| 42 | #include <asm/ubicom32input.h> |
| 43 | |
| 44 | struct ubicom32input_data { |
| 45 | struct ubicom32input_platform_data *pdata; |
| 46 | |
| 47 | struct input_polled_dev *poll_dev; |
| 48 | |
| 49 | /* |
| 50 | * collection of previous states for buttons |
| 51 | */ |
| 52 | u8 prev_state[0]; |
| 53 | }; |
| 54 | |
| 55 | /* |
| 56 | * ubicom32input_poll |
| 57 | */ |
| 58 | static void ubicom32input_poll(struct input_polled_dev *dev) |
| 59 | { |
| 60 | struct ubicom32input_data *ud = |
| 61 | (struct ubicom32input_data *)dev->private; |
| 62 | struct ubicom32input_platform_data *pdata = ud->pdata; |
| 63 | struct input_dev *id = dev->input; |
| 64 | int i; |
| 65 | int sync_needed = 0; |
| 66 | |
| 67 | for (i = 0; i < pdata->nbuttons; i++) { |
| 68 | const struct ubicom32input_button *ub = &pdata->buttons[i]; |
| 69 | int state = 0; |
| 70 | |
| 71 | int val = gpio_get_value(ub->gpio); |
| 72 | |
| 73 | /* |
| 74 | * Check to see if the state changed from the last time we |
| 75 | * looked |
| 76 | */ |
| 77 | if (val == ud->prev_state[i]) { |
| 78 | continue; |
| 79 | } |
| 80 | |
| 81 | /* |
| 82 | * The state has changed, determine if we are "up" or "down" |
| 83 | */ |
| 84 | ud->prev_state[i] = val; |
| 85 | |
| 86 | if ((!val && ub->active_low) || (val && !ub->active_low)) { |
| 87 | state = 1; |
| 88 | } |
| 89 | |
| 90 | input_event(id, ub->type, ub->code, state); |
| 91 | sync_needed = 1; |
| 92 | } |
| 93 | |
| 94 | if (sync_needed) { |
| 95 | input_sync(id); |
| 96 | } |
| 97 | } |
| 98 | |
| 99 | /* |
| 100 | * ubicom32input_probe |
| 101 | */ |
| 102 | static int __devinit ubicom32input_probe(struct platform_device *pdev) |
| 103 | { |
| 104 | int i; |
| 105 | struct ubicom32input_data *ud; |
| 106 | struct input_polled_dev *poll_dev; |
| 107 | struct input_dev *input_dev; |
| 108 | struct ubicom32input_platform_data *pdata; |
| 109 | int ret; |
| 110 | |
| 111 | pdata = pdev->dev.platform_data; |
| 112 | if (!pdata) { |
| 113 | return -EINVAL; |
| 114 | } |
| 115 | |
| 116 | ud = kzalloc(sizeof(struct ubicom32input_data) + |
| 117 | pdata->nbuttons, GFP_KERNEL); |
| 118 | if (!ud) { |
| 119 | return -ENOMEM; |
| 120 | } |
| 121 | ud->pdata = pdata; |
| 122 | |
| 123 | poll_dev = input_allocate_polled_device(); |
| 124 | if (!poll_dev) { |
| 125 | ret = -ENOMEM; |
| 126 | goto fail; |
| 127 | } |
| 128 | |
| 129 | platform_set_drvdata(pdev, ud); |
| 130 | |
| 131 | ud->poll_dev = poll_dev; |
| 132 | poll_dev->private = ud; |
| 133 | poll_dev->poll = ubicom32input_poll; |
| 134 | |
| 135 | /* |
| 136 | * Set the poll interval requested, default to 50 msec |
| 137 | */ |
| 138 | if (pdata->poll_interval) { |
| 139 | poll_dev->poll_interval = pdata->poll_interval; |
| 140 | } else { |
| 141 | poll_dev->poll_interval = 50; |
| 142 | } |
| 143 | |
| 144 | /* |
| 145 | * Setup the input device |
| 146 | */ |
| 147 | input_dev = poll_dev->input; |
| 148 | input_dev->name = pdata->name ? pdata->name : "Ubicom32 Input"; |
| 149 | input_dev->phys = "ubicom32input/input0"; |
| 150 | input_dev->dev.parent = &pdev->dev; |
| 151 | input_dev->id.bustype = BUS_HOST; |
| 152 | |
| 153 | /* |
| 154 | * Reserve the GPIOs |
| 155 | */ |
| 156 | for (i = 0; i < pdata->nbuttons; i++) { |
| 157 | const struct ubicom32input_button *ub = &pdata->buttons[i]; |
| 158 | |
| 159 | ret = gpio_request(ub->gpio, |
| 160 | ub->desc ? ub->desc : "ubicom32input"); |
| 161 | if (ret < 0) { |
| 162 | pr_err("ubicom32input: failed to request " |
| 163 | "GPIO %d ret=%d\n", ub->gpio, ret); |
| 164 | goto fail2; |
| 165 | } |
| 166 | |
| 167 | ret = gpio_direction_input(ub->gpio); |
| 168 | if (ret < 0) { |
| 169 | pr_err("ubicom32input: failed to set " |
| 170 | "GPIO %d to input ret=%d\n", ub->gpio, ret); |
| 171 | goto fail2; |
| 172 | } |
| 173 | |
| 174 | /* |
| 175 | * Set the previous state to the non-active stae |
| 176 | */ |
| 177 | ud->prev_state[i] = ub->active_low; |
| 178 | |
| 179 | input_set_capability(input_dev, |
| 180 | ub->type ? ub->type : EV_KEY, ub->code); |
| 181 | } |
| 182 | |
| 183 | /* |
| 184 | * Register |
| 185 | */ |
| 186 | ret = input_register_polled_device(ud->poll_dev); |
| 187 | if (ret) { |
| 188 | goto fail2; |
| 189 | } |
| 190 | |
| 191 | return 0; |
| 192 | |
| 193 | fail2: |
| 194 | /* |
| 195 | * release the GPIOs we have already requested. |
| 196 | */ |
| 197 | while (--i >= 0) { |
| 198 | gpio_free(pdata->buttons[i].gpio); |
| 199 | } |
| 200 | |
| 201 | fail: |
| 202 | printk(KERN_ERR "Ubicom32Input: Failed to register driver %d", ret); |
| 203 | platform_set_drvdata(pdev, NULL); |
| 204 | input_free_polled_device(poll_dev); |
| 205 | kfree(ud); |
| 206 | return ret; |
| 207 | } |
| 208 | |
| 209 | /* |
| 210 | * ubicom32input_remove |
| 211 | */ |
| 212 | static int __devexit ubicom32input_remove(struct platform_device *dev) |
| 213 | { |
| 214 | struct ubicom32input_data *ud = |
| 215 | (struct ubicom32input_data *)platform_get_drvdata(dev); |
| 216 | int i; |
| 217 | |
| 218 | /* |
| 219 | * Free the GPIOs |
| 220 | */ |
| 221 | for (i = 0; i < ud->pdata->nbuttons; i++) { |
| 222 | gpio_free(ud->pdata->buttons[i].gpio); |
| 223 | } |
| 224 | |
| 225 | platform_set_drvdata(dev, NULL); |
| 226 | input_unregister_polled_device(ud->poll_dev); |
| 227 | input_free_polled_device(ud->poll_dev); |
| 228 | |
| 229 | kfree(ud); |
| 230 | |
| 231 | return 0; |
| 232 | } |
| 233 | |
| 234 | static struct platform_driver ubicom32input_driver = { |
| 235 | .driver = { |
| 236 | .name = "ubicom32input", |
| 237 | .owner = THIS_MODULE, |
| 238 | }, |
| 239 | .probe = ubicom32input_probe, |
| 240 | .remove = __devexit_p(ubicom32input_remove), |
| 241 | }; |
| 242 | |
| 243 | /* |
| 244 | * ubicom32input_init |
| 245 | */ |
| 246 | static int __devinit ubicom32input_init(void) |
| 247 | { |
| 248 | return platform_driver_register(&ubicom32input_driver); |
| 249 | } |
| 250 | |
| 251 | /* |
| 252 | * ubicom32input_exit |
| 253 | */ |
| 254 | static void __exit ubicom32input_exit(void) |
| 255 | { |
| 256 | platform_driver_unregister(&ubicom32input_driver); |
| 257 | } |
| 258 | |
| 259 | module_init(ubicom32input_init); |
| 260 | module_exit(ubicom32input_exit); |
| 261 | |
| 262 | MODULE_AUTHOR("Pat Tjin <pattjin@ubicom.com>"); |
| 263 | MODULE_DESCRIPTION("Ubicom32 Input Driver"); |
| 264 | MODULE_LICENSE("GPL"); |
| 265 | MODULE_ALIAS("platform:ubicom32-input"); |
| 266 | |
