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/pm.h> 27 #include <linux/slab.h> 28 #include <asm/io.h> 29 #include <linux/i2c.h> 30 #include <linux/timer.h> 31 32 #define EVENT_PENDOWN 1 33 #define EVENT_REPEAT 2 34 #define EVENT_PENUP 3 35 36 struct migor_ts_priv { 37 struct i2c_client *client; 38 struct input_dev *input; 39 int irq; 40 }; 41 42 static const u_int8_t migor_ts_ena_seq[17] = { 0x33, 0x22, 0x11, 43 0x01, 0x06, 0x07, }; 44 static const u_int8_t migor_ts_dis_seq[17] = { }; 45 46 static irqreturn_t migor_ts_isr(int irq, void *dev_id) 47 { 48 struct migor_ts_priv *priv = dev_id; 49 unsigned short xpos, ypos; 50 unsigned char event; 51 u_int8_t buf[16]; 52 53 /* 54 * The touch screen controller chip is hooked up to the CPU 55 * using I2C and a single interrupt line. The interrupt line 56 * is pulled low whenever someone taps the screen. To deassert 57 * the interrupt line we need to acknowledge the interrupt by 58 * communicating with the controller over the slow i2c bus. 59 * 60 * Since I2C bus controller may sleep we are using threaded 61 * IRQ here. 62 */ 63 64 memset(buf, 0, sizeof(buf)); 65 66 /* Set Index 0 */ 67 buf[0] = 0; 68 if (i2c_master_send(priv->client, buf, 1) != 1) { 69 dev_err(&priv->client->dev, "Unable to write i2c index\n"); 70 goto out; 71 } 72 73 /* Now do Page Read */ 74 if (i2c_master_recv(priv->client, buf, sizeof(buf)) != sizeof(buf)) { 75 dev_err(&priv->client->dev, "Unable to read i2c page\n"); 76 goto out; 77 } 78 79 ypos = ((buf[9] & 0x03) << 8 | buf[8]); 80 xpos = ((buf[11] & 0x03) << 8 | buf[10]); 81 event = buf[12]; 82 83 switch (event) { 84 case EVENT_PENDOWN: 85 case EVENT_REPEAT: 86 input_report_key(priv->input, BTN_TOUCH, 1); 87 input_report_abs(priv->input, ABS_X, ypos); /*X-Y swap*/ 88 input_report_abs(priv->input, ABS_Y, xpos); 89 input_sync(priv->input); 90 break; 91 92 case EVENT_PENUP: 93 input_report_key(priv->input, BTN_TOUCH, 0); 94 input_sync(priv->input); 95 break; 96 } 97 98 out: 99 return IRQ_HANDLED; 100 } 101 102 static int migor_ts_open(struct input_dev *dev) 103 { 104 struct migor_ts_priv *priv = input_get_drvdata(dev); 105 struct i2c_client *client = priv->client; 106 int count; 107 108 /* enable controller */ 109 count = i2c_master_send(client, migor_ts_ena_seq, 110 sizeof(migor_ts_ena_seq)); 111 if (count != sizeof(migor_ts_ena_seq)) { 112 dev_err(&client->dev, "Unable to enable touchscreen.\n"); 113 return -ENXIO; 114 } 115 116 return 0; 117 } 118 119 static void migor_ts_close(struct input_dev *dev) 120 { 121 struct migor_ts_priv *priv = input_get_drvdata(dev); 122 struct i2c_client *client = priv->client; 123 124 disable_irq(priv->irq); 125 126 /* disable controller */ 127 i2c_master_send(client, migor_ts_dis_seq, sizeof(migor_ts_dis_seq)); 128 129 enable_irq(priv->irq); 130 } 131 132 static int migor_ts_probe(struct i2c_client *client, 133 const struct i2c_device_id *idp) 134 { 135 struct migor_ts_priv *priv; 136 struct input_dev *input; 137 int error; 138 139 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 140 input = input_allocate_device(); 141 if (!priv || !input) { 142 dev_err(&client->dev, "failed to allocate memory\n"); 143 error = -ENOMEM; 144 goto err_free_mem; 145 } 146 147 priv->client = client; 148 priv->input = input; 149 priv->irq = client->irq; 150 151 input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); 152 153 __set_bit(BTN_TOUCH, input->keybit); 154 155 input_set_abs_params(input, ABS_X, 95, 955, 0, 0); 156 input_set_abs_params(input, ABS_Y, 85, 935, 0, 0); 157 158 input->name = client->name; 159 input->id.bustype = BUS_I2C; 160 input->dev.parent = &client->dev; 161 162 input->open = migor_ts_open; 163 input->close = migor_ts_close; 164 165 input_set_drvdata(input, priv); 166 167 error = request_threaded_irq(priv->irq, NULL, migor_ts_isr, 168 IRQF_TRIGGER_LOW | IRQF_ONESHOT, 169 client->name, priv); 170 if (error) { 171 dev_err(&client->dev, "Unable to request touchscreen IRQ.\n"); 172 goto err_free_mem; 173 } 174 175 error = input_register_device(input); 176 if (error) 177 goto err_free_irq; 178 179 i2c_set_clientdata(client, priv); 180 device_init_wakeup(&client->dev, 1); 181 182 return 0; 183 184 err_free_irq: 185 free_irq(priv->irq, priv); 186 err_free_mem: 187 input_free_device(input); 188 kfree(priv); 189 return error; 190 } 191 192 static int migor_ts_remove(struct i2c_client *client) 193 { 194 struct migor_ts_priv *priv = i2c_get_clientdata(client); 195 196 free_irq(priv->irq, priv); 197 input_unregister_device(priv->input); 198 kfree(priv); 199 200 dev_set_drvdata(&client->dev, NULL); 201 202 return 0; 203 } 204 205 static int __maybe_unused migor_ts_suspend(struct device *dev) 206 { 207 struct i2c_client *client = to_i2c_client(dev); 208 struct migor_ts_priv *priv = i2c_get_clientdata(client); 209 210 if (device_may_wakeup(&client->dev)) 211 enable_irq_wake(priv->irq); 212 213 return 0; 214 } 215 216 static int __maybe_unused migor_ts_resume(struct device *dev) 217 { 218 struct i2c_client *client = to_i2c_client(dev); 219 struct migor_ts_priv *priv = i2c_get_clientdata(client); 220 221 if (device_may_wakeup(&client->dev)) 222 disable_irq_wake(priv->irq); 223 224 return 0; 225 } 226 227 static SIMPLE_DEV_PM_OPS(migor_ts_pm, migor_ts_suspend, migor_ts_resume); 228 229 static const struct i2c_device_id migor_ts_id[] = { 230 { "migor_ts", 0 }, 231 { } 232 }; 233 MODULE_DEVICE_TABLE(i2c, migor_ts_id); 234 235 static struct i2c_driver migor_ts_driver = { 236 .driver = { 237 .name = "migor_ts", 238 .pm = &migor_ts_pm, 239 }, 240 .probe = migor_ts_probe, 241 .remove = migor_ts_remove, 242 .id_table = migor_ts_id, 243 }; 244 245 module_i2c_driver(migor_ts_driver); 246 247 MODULE_DESCRIPTION("MigoR Touchscreen driver"); 248 MODULE_AUTHOR("Magnus Damm <damm@opensource.se>"); 249 MODULE_LICENSE("GPL"); 250