1/* 2 * Driver for Motorola PCAP2 touchscreen as found in the EZX phone platform. 3 * 4 * Copyright (C) 2006 Harald Welte <laforge@openezx.org> 5 * Copyright (C) 2009 Daniel Ribeiro <drwyrm@gmail.com> 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 */ 12 13#include <linux/module.h> 14#include <linux/init.h> 15#include <linux/fs.h> 16#include <linux/string.h> 17#include <linux/slab.h> 18#include <linux/pm.h> 19#include <linux/timer.h> 20#include <linux/interrupt.h> 21#include <linux/platform_device.h> 22#include <linux/input.h> 23#include <linux/mfd/ezx-pcap.h> 24 25struct pcap_ts { 26 struct pcap_chip *pcap; 27 struct input_dev *input; 28 struct delayed_work work; 29 u16 x, y; 30 u16 pressure; 31 u8 read_state; 32}; 33 34#define SAMPLE_DELAY 20 /* msecs */ 35 36#define X_AXIS_MIN 0 37#define X_AXIS_MAX 1023 38#define Y_AXIS_MAX X_AXIS_MAX 39#define Y_AXIS_MIN X_AXIS_MIN 40#define PRESSURE_MAX X_AXIS_MAX 41#define PRESSURE_MIN X_AXIS_MIN 42 43static void pcap_ts_read_xy(void *data, u16 res[2]) 44{ 45 struct pcap_ts *pcap_ts = data; 46 47 switch (pcap_ts->read_state) { 48 case PCAP_ADC_TS_M_PRESSURE: 49 /* pressure reading is unreliable */ 50 if (res[0] > PRESSURE_MIN && res[0] < PRESSURE_MAX) 51 pcap_ts->pressure = res[0]; 52 pcap_ts->read_state = PCAP_ADC_TS_M_XY; 53 schedule_delayed_work(&pcap_ts->work, 0); 54 break; 55 case PCAP_ADC_TS_M_XY: 56 pcap_ts->y = res[0]; 57 pcap_ts->x = res[1]; 58 if (pcap_ts->x <= X_AXIS_MIN || pcap_ts->x >= X_AXIS_MAX || 59 pcap_ts->y <= Y_AXIS_MIN || pcap_ts->y >= Y_AXIS_MAX) { 60 /* pen has been released */ 61 input_report_abs(pcap_ts->input, ABS_PRESSURE, 0); 62 input_report_key(pcap_ts->input, BTN_TOUCH, 0); 63 64 pcap_ts->read_state = PCAP_ADC_TS_M_STANDBY; 65 schedule_delayed_work(&pcap_ts->work, 0); 66 } else { 67 /* pen is touching the screen */ 68 input_report_abs(pcap_ts->input, ABS_X, pcap_ts->x); 69 input_report_abs(pcap_ts->input, ABS_Y, pcap_ts->y); 70 input_report_key(pcap_ts->input, BTN_TOUCH, 1); 71 input_report_abs(pcap_ts->input, ABS_PRESSURE, 72 pcap_ts->pressure); 73 74 /* switch back to pressure read mode */ 75 pcap_ts->read_state = PCAP_ADC_TS_M_PRESSURE; 76 schedule_delayed_work(&pcap_ts->work, 77 msecs_to_jiffies(SAMPLE_DELAY)); 78 } 79 input_sync(pcap_ts->input); 80 break; 81 default: 82 dev_warn(&pcap_ts->input->dev, 83 "pcap_ts: Warning, unhandled read_state %d\n", 84 pcap_ts->read_state); 85 break; 86 } 87} 88 89static void pcap_ts_work(struct work_struct *work) 90{ 91 struct delayed_work *dw = container_of(work, struct delayed_work, work); 92 struct pcap_ts *pcap_ts = container_of(dw, struct pcap_ts, work); 93 u8 ch[2]; 94 95 pcap_set_ts_bits(pcap_ts->pcap, 96 pcap_ts->read_state << PCAP_ADC_TS_M_SHIFT); 97 98 if (pcap_ts->read_state == PCAP_ADC_TS_M_STANDBY) 99 return; 100 101 /* start adc conversion */ 102 ch[0] = PCAP_ADC_CH_TS_X1; 103 ch[1] = PCAP_ADC_CH_TS_Y1; 104 pcap_adc_async(pcap_ts->pcap, PCAP_ADC_BANK_1, 0, ch, 105 pcap_ts_read_xy, pcap_ts); 106} 107 108static irqreturn_t pcap_ts_event_touch(int pirq, void *data) 109{ 110 struct pcap_ts *pcap_ts = data; 111 112 if (pcap_ts->read_state == PCAP_ADC_TS_M_STANDBY) { 113 pcap_ts->read_state = PCAP_ADC_TS_M_PRESSURE; 114 schedule_delayed_work(&pcap_ts->work, 0); 115 } 116 return IRQ_HANDLED; 117} 118 119static int pcap_ts_open(struct input_dev *dev) 120{ 121 struct pcap_ts *pcap_ts = input_get_drvdata(dev); 122 123 pcap_ts->read_state = PCAP_ADC_TS_M_STANDBY; 124 schedule_delayed_work(&pcap_ts->work, 0); 125 126 return 0; 127} 128 129static void pcap_ts_close(struct input_dev *dev) 130{ 131 struct pcap_ts *pcap_ts = input_get_drvdata(dev); 132 133 cancel_delayed_work_sync(&pcap_ts->work); 134 135 pcap_ts->read_state = PCAP_ADC_TS_M_NONTS; 136 pcap_set_ts_bits(pcap_ts->pcap, 137 pcap_ts->read_state << PCAP_ADC_TS_M_SHIFT); 138} 139 140static int __devinit pcap_ts_probe(struct platform_device *pdev) 141{ 142 struct input_dev *input_dev; 143 struct pcap_ts *pcap_ts; 144 int err = -ENOMEM; 145 146 pcap_ts = kzalloc(sizeof(*pcap_ts), GFP_KERNEL); 147 if (!pcap_ts) 148 return err; 149 150 pcap_ts->pcap = dev_get_drvdata(pdev->dev.parent); 151 platform_set_drvdata(pdev, pcap_ts); 152 153 input_dev = input_allocate_device(); 154 if (!input_dev) 155 goto fail; 156 157 INIT_DELAYED_WORK(&pcap_ts->work, pcap_ts_work); 158 159 pcap_ts->read_state = PCAP_ADC_TS_M_NONTS; 160 pcap_set_ts_bits(pcap_ts->pcap, 161 pcap_ts->read_state << PCAP_ADC_TS_M_SHIFT); 162 163 pcap_ts->input = input_dev; 164 input_set_drvdata(input_dev, pcap_ts); 165 166 input_dev->name = "pcap-touchscreen"; 167 input_dev->phys = "pcap_ts/input0"; 168 input_dev->id.bustype = BUS_HOST; 169 input_dev->id.vendor = 0x0001; 170 input_dev->id.product = 0x0002; 171 input_dev->id.version = 0x0100; 172 input_dev->dev.parent = &pdev->dev; 173 input_dev->open = pcap_ts_open; 174 input_dev->close = pcap_ts_close; 175 176 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); 177 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); 178 input_set_abs_params(input_dev, ABS_X, X_AXIS_MIN, X_AXIS_MAX, 0, 0); 179 input_set_abs_params(input_dev, ABS_Y, Y_AXIS_MIN, Y_AXIS_MAX, 0, 0); 180 input_set_abs_params(input_dev, ABS_PRESSURE, PRESSURE_MIN, 181 PRESSURE_MAX, 0, 0); 182 183 err = input_register_device(pcap_ts->input); 184 if (err) 185 goto fail_allocate; 186 187 err = request_irq(pcap_to_irq(pcap_ts->pcap, PCAP_IRQ_TS), 188 pcap_ts_event_touch, 0, "Touch Screen", pcap_ts); 189 if (err) 190 goto fail_register; 191 192 return 0; 193 194fail_register: 195 input_unregister_device(input_dev); 196 goto fail; 197fail_allocate: 198 input_free_device(input_dev); 199fail: 200 kfree(pcap_ts); 201 202 return err; 203} 204 205static int __devexit pcap_ts_remove(struct platform_device *pdev) 206{ 207 struct pcap_ts *pcap_ts = platform_get_drvdata(pdev); 208 209 free_irq(pcap_to_irq(pcap_ts->pcap, PCAP_IRQ_TS), pcap_ts); 210 cancel_delayed_work_sync(&pcap_ts->work); 211 212 input_unregister_device(pcap_ts->input); 213 214 kfree(pcap_ts); 215 216 return 0; 217} 218 219#ifdef CONFIG_PM 220static int pcap_ts_suspend(struct device *dev) 221{ 222 struct pcap_ts *pcap_ts = dev_get_drvdata(dev); 223 224 pcap_set_ts_bits(pcap_ts->pcap, PCAP_ADC_TS_REF_LOWPWR); 225 return 0; 226} 227 228static int pcap_ts_resume(struct device *dev) 229{ 230 struct pcap_ts *pcap_ts = dev_get_drvdata(dev); 231 232 pcap_set_ts_bits(pcap_ts->pcap, 233 pcap_ts->read_state << PCAP_ADC_TS_M_SHIFT); 234 return 0; 235} 236 237static const struct dev_pm_ops pcap_ts_pm_ops = { 238 .suspend = pcap_ts_suspend, 239 .resume = pcap_ts_resume, 240}; 241#define PCAP_TS_PM_OPS (&pcap_ts_pm_ops) 242#else 243#define PCAP_TS_PM_OPS NULL 244#endif 245 246static struct platform_driver pcap_ts_driver = { 247 .probe = pcap_ts_probe, 248 .remove = __devexit_p(pcap_ts_remove), 249 .driver = { 250 .name = "pcap-ts", 251 .owner = THIS_MODULE, 252 .pm = PCAP_TS_PM_OPS, 253 }, 254}; 255 256static int __init pcap_ts_init(void) 257{ 258 return platform_driver_register(&pcap_ts_driver); 259} 260 261static void __exit pcap_ts_exit(void) 262{ 263 platform_driver_unregister(&pcap_ts_driver); 264} 265 266module_init(pcap_ts_init); 267module_exit(pcap_ts_exit); 268 269MODULE_DESCRIPTION("Motorola PCAP2 touchscreen driver"); 270MODULE_AUTHOR("Daniel Ribeiro / Harald Welte"); 271MODULE_LICENSE("GPL"); 272MODULE_ALIAS("platform:pcap_ts"); 273