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 
23 MODULE_AUTHOR("Kristoffer Ericson <kristoffer.ericson@gmail.com>");
24 MODULE_DESCRIPTION("HP Jornada 710/720/728 touchscreen driver");
25 MODULE_LICENSE("GPL v2");
26 
27 struct 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 
34 static 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 
53 static 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 
64 static 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(jornada_ts->gpio)) {
73 		input_report_key(input, BTN_TOUCH, 0);
74 		input_sync(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(jornada_ts->x_data);
83 			y = jornada720_ts_average(jornada_ts->y_data);
84 
85 			input_report_key(input, BTN_TOUCH, 1);
86 			input_report_abs(input, ABS_X, x);
87 			input_report_abs(input, ABS_Y, y);
88 			input_sync(input);
89 		}
90 
91 		jornada_ssp_end();
92 	}
93 
94 	return IRQ_HANDLED;
95 }
96 
97 static 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(&pdev->dev, 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, jornada_ts);
112 
113 	jornada_ts->gpio = devm_gpiod_get(&pdev->dev, "penup", GPIOD_IN);
114 	if (IS_ERR(jornada_ts->gpio))
115 		return PTR_ERR(jornada_ts->gpio);
116 
117 	irq = gpiod_to_irq(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(input_dev, ABS_X, 270, 3900, 0, 0);
131 	input_set_abs_params(input_dev, ABS_Y, 180, 3700, 0, 0);
132 
133 	error = devm_request_irq(&pdev->dev, irq, jornada720_ts_interrupt,
134 				 IRQF_TRIGGER_RISING,
135 				 "HP7XX Touchscreen driver", 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 */
149 MODULE_ALIAS("platform:jornada_ts");
150 
151 static struct platform_driver jornada720_ts_driver = {
152 	.probe		= jornada720_ts_probe,
153 	.driver		= {
154 		.name	= "jornada_ts",
155 	},
156 };
157 module_platform_driver(jornada720_ts_driver);
158