1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
|
// SPDX-License-Identifier: GPL-2.0
/*
* Raspberry Pi firmware based touchscreen driver
*
* Copyright (C) 2015, 2017 Raspberry Pi
* Copyright (C) 2018 Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
*/
#include <linux/io.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/bitops.h>
#include <linux/dma-mapping.h>
#include <linux/platform_device.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/input/touchscreen.h>
#include <soc/bcm2835/raspberrypi-firmware.h>
#define RPI_TS_DEFAULT_WIDTH 800
#define RPI_TS_DEFAULT_HEIGHT 480
#define RPI_TS_MAX_SUPPORTED_POINTS 10
#define RPI_TS_FTS_TOUCH_DOWN 0
#define RPI_TS_FTS_TOUCH_CONTACT 2
#define RPI_TS_POLL_INTERVAL 17 /* 60fps */
#define RPI_TS_NPOINTS_REG_INVALIDATE 99
struct rpi_ts {
struct platform_device *pdev;
struct input_dev *input;
struct touchscreen_properties prop;
void __iomem *fw_regs_va;
dma_addr_t fw_regs_phys;
int known_ids;
};
struct rpi_ts_regs {
u8 device_mode;
u8 gesture_id;
u8 num_points;
struct rpi_ts_touch {
u8 xh;
u8 xl;
u8 yh;
u8 yl;
u8 pressure; /* Not supported */
u8 area; /* Not supported */
} point[RPI_TS_MAX_SUPPORTED_POINTS];
};
static void rpi_ts_poll(struct input_dev *input)
{
struct rpi_ts *ts = input_get_drvdata(input);
struct rpi_ts_regs regs;
int modified_ids = 0;
long released_ids;
int event_type;
int touchid;
int x, y;
int i;
memcpy_fromio(®s, ts->fw_regs_va, sizeof(regs));
/*
* We poll the memory based register copy of the touchscreen chip using
* the number of points register to know whether the copy has been
* updated (we write 99 to the memory copy, the GPU will write between
* 0 - 10 points)
*/
iowrite8(RPI_TS_NPOINTS_REG_INVALIDATE,
ts->fw_regs_va + offsetof(struct rpi_ts_regs, num_points));
if (regs.num_points == RPI_TS_NPOINTS_REG_INVALIDATE ||
(regs.num_points == 0 && ts->known_ids == 0))
return;
for (i = 0; i < regs.num_points; i++) {
x = (((int)regs.point[i].xh & 0xf) << 8) + regs.point[i].xl;
y = (((int)regs.point[i].yh & 0xf) << 8) + regs.point[i].yl;
touchid = (regs.point[i].yh >> 4) & 0xf;
event_type = (regs.point[i].xh >> 6) & 0x03;
modified_ids |= BIT(touchid);
if (event_type == RPI_TS_FTS_TOUCH_DOWN ||
event_type == RPI_TS_FTS_TOUCH_CONTACT) {
input_mt_slot(input, touchid);
input_mt_report_slot_state(input, MT_TOOL_FINGER, 1);
touchscreen_report_pos(input, &ts->prop, x, y, true);
}
}
released_ids = ts->known_ids & ~modified_ids;
for_each_set_bit(i, &released_ids, RPI_TS_MAX_SUPPORTED_POINTS) {
input_mt_slot(input, i);
input_mt_report_slot_inactive(input);
modified_ids &= ~(BIT(i));
}
ts->known_ids = modified_ids;
input_mt_sync_frame(input);
input_sync(input);
}
static void rpi_ts_dma_cleanup(void *data)
{
struct rpi_ts *ts = data;
struct device *dev = &ts->pdev->dev;
dma_free_coherent(dev, PAGE_SIZE, ts->fw_regs_va, ts->fw_regs_phys);
}
static int rpi_ts_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct input_dev *input;
struct device_node *fw_node;
struct rpi_firmware *fw;
struct rpi_ts *ts;
u32 touchbuf;
int error;
fw_node = of_get_parent(np);
if (!fw_node) {
dev_err(dev, "Missing firmware node\n");
return -ENOENT;
}
fw = rpi_firmware_get(fw_node);
of_node_put(fw_node);
if (!fw)
return -EPROBE_DEFER;
ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
if (!ts)
return -ENOMEM;
ts->pdev = pdev;
ts->fw_regs_va = dma_alloc_coherent(dev, PAGE_SIZE, &ts->fw_regs_phys,
GFP_KERNEL);
if (!ts->fw_regs_va) {
dev_err(dev, "failed to dma_alloc_coherent\n");
return -ENOMEM;
}
error = devm_add_action_or_reset(dev, rpi_ts_dma_cleanup, ts);
if (error) {
dev_err(dev, "failed to devm_add_action_or_reset, %d\n", error);
return error;
}
touchbuf = (u32)ts->fw_regs_phys;
error = rpi_firmware_property(fw, RPI_FIRMWARE_FRAMEBUFFER_SET_TOUCHBUF,
&touchbuf, sizeof(touchbuf));
if (error || touchbuf != 0) {
dev_warn(dev, "Failed to set touchbuf, %d\n", error);
return error;
}
input = devm_input_allocate_device(dev);
if (!input) {
dev_err(dev, "Failed to allocate input device\n");
return -ENOMEM;
}
ts->input = input;
input_set_drvdata(input, ts);
input->name = "raspberrypi-ts";
input->id.bustype = BUS_HOST;
input_set_abs_params(input, ABS_MT_POSITION_X, 0,
RPI_TS_DEFAULT_WIDTH, 0, 0);
input_set_abs_params(input, ABS_MT_POSITION_Y, 0,
RPI_TS_DEFAULT_HEIGHT, 0, 0);
touchscreen_parse_properties(input, true, &ts->prop);
error = input_mt_init_slots(input, RPI_TS_MAX_SUPPORTED_POINTS,
INPUT_MT_DIRECT);
if (error) {
dev_err(dev, "could not init mt slots, %d\n", error);
return error;
}
error = input_setup_polling(input, rpi_ts_poll);
if (error) {
dev_err(dev, "could not set up polling mode, %d\n", error);
return error;
}
input_set_poll_interval(input, RPI_TS_POLL_INTERVAL);
error = input_register_device(input);
if (error) {
dev_err(dev, "could not register input device, %d\n", error);
return error;
}
return 0;
}
static const struct of_device_id rpi_ts_match[] = {
{ .compatible = "raspberrypi,firmware-ts", },
{},
};
MODULE_DEVICE_TABLE(of, rpi_ts_match);
static struct platform_driver rpi_ts_driver = {
.driver = {
.name = "raspberrypi-ts",
.of_match_table = rpi_ts_match,
},
.probe = rpi_ts_probe,
};
module_platform_driver(rpi_ts_driver);
MODULE_AUTHOR("Gordon Hollingworth");
MODULE_AUTHOR("Nicolas Saenz Julienne <nsaenzjulienne@suse.de>");
MODULE_DESCRIPTION("Raspberry Pi firmware based touchscreen driver");
MODULE_LICENSE("GPL v2");
|
