1/* 2 * Touch Screen driver for Renesas MIGO-R Platform 3 * 4 * Copyright (c) 2008 Magnus Damm 5 * Copyright (c) 2007 Ujjwal Pande <ujjwal@kenati.com>, 6 * Kenati Technologies Pvt Ltd. 7 * 8 * This file is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public 10 * License as published by the Free Software Foundation; either 11 * version 2 of the License, or (at your option) any later version. 12 * 13 * This file is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public 19 * License along with this library; if not, write to the Free Software 20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 21 */ 22#include <linux/module.h> 23#include <linux/kernel.h> 24#include <linux/input.h> 25#include <linux/interrupt.h> 26#include <linux/slab.h> 27#include <asm/io.h> 28#include <linux/i2c.h> 29#include <linux/timer.h> 30 31#define EVENT_PENDOWN 1 32#define EVENT_REPEAT 2 33#define EVENT_PENUP 3 34 35struct migor_ts_priv { 36 struct i2c_client *client; 37 struct input_dev *input; 38 struct delayed_work work; 39 int irq; 40}; 41 42static const u_int8_t migor_ts_ena_seq[17] = { 0x33, 0x22, 0x11, 43 0x01, 0x06, 0x07, }; 44static const u_int8_t migor_ts_dis_seq[17] = { }; 45 46static void migor_ts_poscheck(struct work_struct *work) 47{ 48 struct migor_ts_priv *priv = container_of(work, 49 struct migor_ts_priv, 50 work.work); 51 unsigned short xpos, ypos; 52 unsigned char event; 53 u_int8_t buf[16]; 54 55 memset(buf, 0, sizeof(buf)); 56 57 /* Set Index 0 */ 58 buf[0] = 0; 59 if (i2c_master_send(priv->client, buf, 1) != 1) { 60 dev_err(&priv->client->dev, "Unable to write i2c index\n"); 61 goto out; 62 } 63 64 /* Now do Page Read */ 65 if (i2c_master_recv(priv->client, buf, sizeof(buf)) != sizeof(buf)) { 66 dev_err(&priv->client->dev, "Unable to read i2c page\n"); 67 goto out; 68 } 69 70 ypos = ((buf[9] & 0x03) << 8 | buf[8]); 71 xpos = ((buf[11] & 0x03) << 8 | buf[10]); 72 event = buf[12]; 73 74 if (event == EVENT_PENDOWN || event == EVENT_REPEAT) { 75 input_report_key(priv->input, BTN_TOUCH, 1); 76 input_report_abs(priv->input, ABS_X, ypos); /*X-Y swap*/ 77 input_report_abs(priv->input, ABS_Y, xpos); 78 input_sync(priv->input); 79 } else if (event == EVENT_PENUP) { 80 input_report_key(priv->input, BTN_TOUCH, 0); 81 input_sync(priv->input); 82 } 83 out: 84 enable_irq(priv->irq); 85} 86 87static irqreturn_t migor_ts_isr(int irq, void *dev_id) 88{ 89 struct migor_ts_priv *priv = dev_id; 90 91 /* the touch screen controller chip is hooked up to the cpu 92 * using i2c and a single interrupt line. the interrupt line 93 * is pulled low whenever someone taps the screen. to deassert 94 * the interrupt line we need to acknowledge the interrupt by 95 * communicating with the controller over the slow i2c bus. 96 * 97 * we can't acknowledge from interrupt context since the i2c 98 * bus controller may sleep, so we just disable the interrupt 99 * here and handle the acknowledge using delayed work. 100 */ 101 102 disable_irq_nosync(irq); 103 schedule_delayed_work(&priv->work, HZ / 20); 104 105 return IRQ_HANDLED; 106} 107 108 109static int migor_ts_open(struct input_dev *dev) 110{ 111 struct migor_ts_priv *priv = input_get_drvdata(dev); 112 struct i2c_client *client = priv->client; 113 int count; 114 115 /* enable controller */ 116 count = i2c_master_send(client, migor_ts_ena_seq, 117 sizeof(migor_ts_ena_seq)); 118 if (count != sizeof(migor_ts_ena_seq)) { 119 dev_err(&client->dev, "Unable to enable touchscreen.\n"); 120 return -ENXIO; 121 } 122 123 return 0; 124} 125 126static void migor_ts_close(struct input_dev *dev) 127{ 128 struct migor_ts_priv *priv = input_get_drvdata(dev); 129 struct i2c_client *client = priv->client; 130 131 disable_irq(priv->irq); 132 133 /* cancel pending work and wait for migor_ts_poscheck() to finish */ 134 if (cancel_delayed_work_sync(&priv->work)) { 135 /* 136 * if migor_ts_poscheck was canceled we need to enable IRQ 137 * here to balance disable done in migor_ts_isr. 138 */ 139 enable_irq(priv->irq); 140 } 141 142 /* disable controller */ 143 i2c_master_send(client, migor_ts_dis_seq, sizeof(migor_ts_dis_seq)); 144 145 enable_irq(priv->irq); 146} 147 148static int migor_ts_probe(struct i2c_client *client, 149 const struct i2c_device_id *idp) 150{ 151 struct migor_ts_priv *priv; 152 struct input_dev *input; 153 int error; 154 155 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 156 if (!priv) { 157 dev_err(&client->dev, "failed to allocate driver data\n"); 158 error = -ENOMEM; 159 goto err0; 160 } 161 162 dev_set_drvdata(&client->dev, priv); 163 164 input = input_allocate_device(); 165 if (!input) { 166 dev_err(&client->dev, "Failed to allocate input device.\n"); 167 error = -ENOMEM; 168 goto err1; 169 } 170 171 input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); 172 input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); 173 174 input_set_abs_params(input, ABS_X, 95, 955, 0, 0); 175 input_set_abs_params(input, ABS_Y, 85, 935, 0, 0); 176 177 input->name = client->name; 178 input->id.bustype = BUS_I2C; 179 input->dev.parent = &client->dev; 180 181 input->open = migor_ts_open; 182 input->close = migor_ts_close; 183 184 input_set_drvdata(input, priv); 185 186 priv->client = client; 187 priv->input = input; 188 INIT_DELAYED_WORK(&priv->work, migor_ts_poscheck); 189 priv->irq = client->irq; 190 191 error = input_register_device(input); 192 if (error) 193 goto err1; 194 195 error = request_irq(priv->irq, migor_ts_isr, IRQF_TRIGGER_LOW, 196 client->name, priv); 197 if (error) { 198 dev_err(&client->dev, "Unable to request touchscreen IRQ.\n"); 199 goto err2; 200 } 201 202 device_init_wakeup(&client->dev, 1); 203 return 0; 204 205 err2: 206 input_unregister_device(input); 207 input = NULL; /* so we dont try to free it below */ 208 err1: 209 input_free_device(input); 210 kfree(priv); 211 err0: 212 dev_set_drvdata(&client->dev, NULL); 213 return error; 214} 215 216static int migor_ts_remove(struct i2c_client *client) 217{ 218 struct migor_ts_priv *priv = dev_get_drvdata(&client->dev); 219 220 free_irq(priv->irq, priv); 221 input_unregister_device(priv->input); 222 kfree(priv); 223 224 dev_set_drvdata(&client->dev, NULL); 225 226 return 0; 227} 228 229static int migor_ts_suspend(struct i2c_client *client, pm_message_t mesg) 230{ 231 struct migor_ts_priv *priv = dev_get_drvdata(&client->dev); 232 233 if (device_may_wakeup(&client->dev)) 234 enable_irq_wake(priv->irq); 235 236 return 0; 237} 238 239static int migor_ts_resume(struct i2c_client *client) 240{ 241 struct migor_ts_priv *priv = dev_get_drvdata(&client->dev); 242 243 if (device_may_wakeup(&client->dev)) 244 disable_irq_wake(priv->irq); 245 246 return 0; 247} 248 249static const struct i2c_device_id migor_ts_id[] = { 250 { "migor_ts", 0 }, 251 { } 252}; 253MODULE_DEVICE_TABLE(i2c, migor_ts); 254 255static struct i2c_driver migor_ts_driver = { 256 .driver = { 257 .name = "migor_ts", 258 }, 259 .probe = migor_ts_probe, 260 .remove = migor_ts_remove, 261 .suspend = migor_ts_suspend, 262 .resume = migor_ts_resume, 263 .id_table = migor_ts_id, 264}; 265 266static int __init migor_ts_init(void) 267{ 268 return i2c_add_driver(&migor_ts_driver); 269} 270 271static void __exit migor_ts_exit(void) 272{ 273 i2c_del_driver(&migor_ts_driver); 274} 275 276MODULE_DESCRIPTION("MigoR Touchscreen driver"); 277MODULE_AUTHOR("Magnus Damm <damm@opensource.se>"); 278MODULE_LICENSE("GPL"); 279 280module_init(migor_ts_init); 281module_exit(migor_ts_exit); 282