input/touchscreen/hp680_ts_input.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 #include <linux/input.h>
0003 #include <linux/module.h>
0004 #include <linux/init.h>
0005 #include <linux/interrupt.h>
0006 #include <asm/io.h>
0007 #include <asm/delay.h>
0008 #include <asm/adc.h>
0009 #include <mach/hp6xx.h>
0010
0011 #define MODNAME "hp680_ts_input"
0012
0013 #define HP680_TS_ABS_X_MIN  40
0014 #define HP680_TS_ABS_X_MAX  950
0015 #define HP680_TS_ABS_Y_MIN  80
0016 #define HP680_TS_ABS_Y_MAX  910
0017
0018 #define PHDR    0xa400012e
0019 #define SCPDR   0xa4000136
0020
0021 static void do_softint(struct work_struct *work);
0022
0023 static struct input_dev *hp680_ts_dev;
0024 static DECLARE_DELAYED_WORK(work, do_softint);
0025
0026 static void do_softint(struct work_struct *work)
0027 {
0028     int absx = 0, absy = 0;
0029     u8 scpdr;
0030     int touched = 0;
0031
0032     if (__raw_readb(PHDR) & PHDR_TS_PEN_DOWN) {
0033         scpdr = __raw_readb(SCPDR);
0034         scpdr |= SCPDR_TS_SCAN_ENABLE;
0035         scpdr &= ~SCPDR_TS_SCAN_Y;
0036         __raw_writeb(scpdr, SCPDR);
0037         udelay(30);
0038
0039         absy = adc_single(ADC_CHANNEL_TS_Y);
0040
0041         scpdr = __raw_readb(SCPDR);
0042         scpdr |= SCPDR_TS_SCAN_Y;
0043         scpdr &= ~SCPDR_TS_SCAN_X;
0044         __raw_writeb(scpdr, SCPDR);
0045         udelay(30);
0046
0047         absx = adc_single(ADC_CHANNEL_TS_X);
0048
0049         scpdr = __raw_readb(SCPDR);
0050         scpdr |= SCPDR_TS_SCAN_X;
0051         scpdr &= ~SCPDR_TS_SCAN_ENABLE;
0052         __raw_writeb(scpdr, SCPDR);
0053         udelay(100);
0054         touched = __raw_readb(PHDR) & PHDR_TS_PEN_DOWN;
0055     }
0056
0057     if (touched) {
0058         input_report_key(hp680_ts_dev, BTN_TOUCH, 1);
0059         input_report_abs(hp680_ts_dev, ABS_X, absx);
0060         input_report_abs(hp680_ts_dev, ABS_Y, absy);
0061     } else {
0062         input_report_key(hp680_ts_dev, BTN_TOUCH, 0);
0063     }
0064
0065     input_sync(hp680_ts_dev);
0066     enable_irq(HP680_TS_IRQ);
0067 }
0068
0069 static irqreturn_t hp680_ts_interrupt(int irq, void *dev)
0070 {
0071     disable_irq_nosync(irq);
0072     schedule_delayed_work(&work, HZ / 20);
0073
0074     return IRQ_HANDLED;
0075 }
0076
0077 static int __init hp680_ts_init(void)
0078 {
0079     int err;
0080
0081     hp680_ts_dev = input_allocate_device();
0082     if (!hp680_ts_dev)
0083         return -ENOMEM;
0084
0085     hp680_ts_dev->evbit[0] = BIT_MASK(EV_ABS) | BIT_MASK(EV_KEY);
0086     hp680_ts_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
0087
0088     input_set_abs_params(hp680_ts_dev, ABS_X,
0089         HP680_TS_ABS_X_MIN, HP680_TS_ABS_X_MAX, 0, 0);
0090     input_set_abs_params(hp680_ts_dev, ABS_Y,
0091         HP680_TS_ABS_Y_MIN, HP680_TS_ABS_Y_MAX, 0, 0);
0092
0093     hp680_ts_dev->name = "HP Jornada touchscreen";
0094     hp680_ts_dev->phys = "hp680_ts/input0";
0095
0096     if (request_irq(HP680_TS_IRQ, hp680_ts_interrupt,
0097             0, MODNAME, NULL) < 0) {
0098         printk(KERN_ERR "hp680_touchscreen.c: Can't allocate irq %d\n",
0099                HP680_TS_IRQ);
0100         err = -EBUSY;
0101         goto fail1;
0102     }
0103
0104     err = input_register_device(hp680_ts_dev);
0105     if (err)
0106         goto fail2;
0107
0108     return 0;
0109
0110  fail2: free_irq(HP680_TS_IRQ, NULL);
0111     cancel_delayed_work_sync(&work);
0112  fail1: input_free_device(hp680_ts_dev);
0113     return err;
0114 }
0115
0116 static void __exit hp680_ts_exit(void)
0117 {
0118     free_irq(HP680_TS_IRQ, NULL);
0119     cancel_delayed_work_sync(&work);
0120     input_unregister_device(hp680_ts_dev);
0121 }
0122
0123 module_init(hp680_ts_init);
0124 module_exit(hp680_ts_exit);
0125
0126 MODULE_AUTHOR("Andriy Skulysh, askulysh@image.kiev.ua");
0127 MODULE_DESCRIPTION("HP Jornada 680 touchscreen driver");
0128 MODULE_LICENSE("GPL");