1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * drivers/input/touchscreen/jornada720_ts.c
4 *
5 * Copyright (C) 2007 Kristoffer Ericson <Kristoffer.Ericson@gmail.com>
6 *
7 * Copyright (C) 2006 Filip Zyzniewski <filip.zyzniewski@tefnet.pl>
8 * based on HP Jornada 56x touchscreen driver by Alex Lange <chicken@handhelds.org>
9 *
10 * HP Jornada 710/720/729 Touchscreen Driver
11 */
12
13#include <linux/gpio/consumer.h>
14#include <linux/platform_device.h>
15#include <linux/input.h>
16#include <linux/interrupt.h>
17#include <linux/module.h>
18#include <linux/slab.h>
19#include <linux/io.h>
20
21#include <mach/jornada720.h>
22
23MODULE_AUTHOR("Kristoffer Ericson <kristoffer.ericson@gmail.com>");
24MODULE_DESCRIPTION("HP Jornada 710/720/728 touchscreen driver");
25MODULE_LICENSE("GPL v2");
26
27struct jornada_ts {
28 struct input_dev *dev;
29 struct gpio_desc *gpio;
30 int x_data[4]; /* X sample values */
31 int y_data[4]; /* Y sample values */
32};
33
34static void jornada720_ts_collect_data(struct jornada_ts *jornada_ts)
35{
36 /* 3 low word X samples */
37 jornada_ts->x_data[0] = jornada_ssp_byte(TXDUMMY);
38 jornada_ts->x_data[1] = jornada_ssp_byte(TXDUMMY);
39 jornada_ts->x_data[2] = jornada_ssp_byte(TXDUMMY);
40
41 /* 3 low word Y samples */
42 jornada_ts->y_data[0] = jornada_ssp_byte(TXDUMMY);
43 jornada_ts->y_data[1] = jornada_ssp_byte(TXDUMMY);
44 jornada_ts->y_data[2] = jornada_ssp_byte(TXDUMMY);
45
46 /* combined x samples bits */
47 jornada_ts->x_data[3] = jornada_ssp_byte(TXDUMMY);
48
49 /* combined y samples bits */
50 jornada_ts->y_data[3] = jornada_ssp_byte(TXDUMMY);
51}
52
53static int jornada720_ts_average(int coords[4])
54{
55 int coord, high_bits = coords[3];
56
57 coord = coords[0] | ((high_bits & 0x03) << 8);
58 coord += coords[1] | ((high_bits & 0x0c) << 6);
59 coord += coords[2] | ((high_bits & 0x30) << 4);
60
61 return coord / 3;
62}
63
64static irqreturn_t jornada720_ts_interrupt(int irq, void *dev_id)
65{
66 struct platform_device *pdev = dev_id;
67 struct jornada_ts *jornada_ts = platform_get_drvdata(pdev);
68 struct input_dev *input = jornada_ts->dev;
69 int x, y;
70
71 /* If gpio is high then report pen up */
72 if (gpiod_get_value(desc: jornada_ts->gpio)) {
73 input_report_key(dev: input, BTN_TOUCH, value: 0);
74 input_sync(dev: input);
75 } else {
76 jornada_ssp_start();
77
78 /* proper reply to request is always TXDUMMY */
79 if (jornada_ssp_inout(GETTOUCHSAMPLES) == TXDUMMY) {
80 jornada720_ts_collect_data(jornada_ts);
81
82 x = jornada720_ts_average(coords: jornada_ts->x_data);
83 y = jornada720_ts_average(coords: jornada_ts->y_data);
84
85 input_report_key(dev: input, BTN_TOUCH, value: 1);
86 input_report_abs(dev: input, ABS_X, value: x);
87 input_report_abs(dev: input, ABS_Y, value: y);
88 input_sync(dev: input);
89 }
90
91 jornada_ssp_end();
92 }
93
94 return IRQ_HANDLED;
95}
96
97static int jornada720_ts_probe(struct platform_device *pdev)
98{
99 struct jornada_ts *jornada_ts;
100 struct input_dev *input_dev;
101 int error, irq;
102
103 jornada_ts = devm_kzalloc(dev: &pdev->dev, size: sizeof(*jornada_ts), GFP_KERNEL);
104 if (!jornada_ts)
105 return -ENOMEM;
106
107 input_dev = devm_input_allocate_device(&pdev->dev);
108 if (!input_dev)
109 return -ENOMEM;
110
111 platform_set_drvdata(pdev, data: jornada_ts);
112
113 jornada_ts->gpio = devm_gpiod_get(dev: &pdev->dev, con_id: "penup", flags: GPIOD_IN);
114 if (IS_ERR(ptr: jornada_ts->gpio))
115 return PTR_ERR(ptr: jornada_ts->gpio);
116
117 irq = gpiod_to_irq(desc: jornada_ts->gpio);
118 if (irq <= 0)
119 return irq < 0 ? irq : -EINVAL;
120
121 jornada_ts->dev = input_dev;
122
123 input_dev->name = "HP Jornada 7xx Touchscreen";
124 input_dev->phys = "jornadats/input0";
125 input_dev->id.bustype = BUS_HOST;
126 input_dev->dev.parent = &pdev->dev;
127
128 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
129 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
130 input_set_abs_params(dev: input_dev, ABS_X, min: 270, max: 3900, fuzz: 0, flat: 0);
131 input_set_abs_params(dev: input_dev, ABS_Y, min: 180, max: 3700, fuzz: 0, flat: 0);
132
133 error = devm_request_irq(dev: &pdev->dev, irq, handler: jornada720_ts_interrupt,
134 IRQF_TRIGGER_RISING,
135 devname: "HP7XX Touchscreen driver", dev_id: pdev);
136 if (error) {
137 dev_err(&pdev->dev, "HP7XX TS : Unable to acquire irq!\n");
138 return error;
139 }
140
141 error = input_register_device(jornada_ts->dev);
142 if (error)
143 return error;
144
145 return 0;
146}
147
148/* work with hotplug and coldplug */
149MODULE_ALIAS("platform:jornada_ts");
150
151static struct platform_driver jornada720_ts_driver = {
152 .probe = jornada720_ts_probe,
153 .driver = {
154 .name = "jornada_ts",
155 },
156};
157module_platform_driver(jornada720_ts_driver);
158

source code of linux/drivers/input/touchscreen/jornada720_ts.c