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authorJonathan Herman <hermanjl@cs.unc.edu>2013-01-22 10:38:37 -0500
committerJonathan Herman <hermanjl@cs.unc.edu>2013-01-22 10:38:37 -0500
commitfcc9d2e5a6c89d22b8b773a64fb4ad21ac318446 (patch)
treea57612d1888735a2ec7972891b68c1ac5ec8faea /drivers/input/misc/gpio_axis.c
parent8dea78da5cee153b8af9c07a2745f6c55057fe12 (diff)
Added missing tegra files.HEADmaster
Diffstat (limited to 'drivers/input/misc/gpio_axis.c')
-rw-r--r--drivers/input/misc/gpio_axis.c192
1 files changed, 192 insertions, 0 deletions
diff --git a/drivers/input/misc/gpio_axis.c b/drivers/input/misc/gpio_axis.c
new file mode 100644
index 00000000000..0acf4a576f5
--- /dev/null
+++ b/drivers/input/misc/gpio_axis.c
@@ -0,0 +1,192 @@
1/* drivers/input/misc/gpio_axis.c
2 *
3 * Copyright (C) 2007 Google, Inc.
4 *
5 * This software is licensed under the terms of the GNU General Public
6 * License version 2, as published by the Free Software Foundation, and
7 * may be copied, distributed, and modified under those terms.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 */
15
16#include <linux/kernel.h>
17#include <linux/gpio.h>
18#include <linux/gpio_event.h>
19#include <linux/interrupt.h>
20#include <linux/slab.h>
21
22struct gpio_axis_state {
23 struct gpio_event_input_devs *input_devs;
24 struct gpio_event_axis_info *info;
25 uint32_t pos;
26};
27
28uint16_t gpio_axis_4bit_gray_map_table[] = {
29 [0x0] = 0x0, [0x1] = 0x1, /* 0000 0001 */
30 [0x3] = 0x2, [0x2] = 0x3, /* 0011 0010 */
31 [0x6] = 0x4, [0x7] = 0x5, /* 0110 0111 */
32 [0x5] = 0x6, [0x4] = 0x7, /* 0101 0100 */
33 [0xc] = 0x8, [0xd] = 0x9, /* 1100 1101 */
34 [0xf] = 0xa, [0xe] = 0xb, /* 1111 1110 */
35 [0xa] = 0xc, [0xb] = 0xd, /* 1010 1011 */
36 [0x9] = 0xe, [0x8] = 0xf, /* 1001 1000 */
37};
38uint16_t gpio_axis_4bit_gray_map(struct gpio_event_axis_info *info, uint16_t in)
39{
40 return gpio_axis_4bit_gray_map_table[in];
41}
42
43uint16_t gpio_axis_5bit_singletrack_map_table[] = {
44 [0x10] = 0x00, [0x14] = 0x01, [0x1c] = 0x02, /* 10000 10100 11100 */
45 [0x1e] = 0x03, [0x1a] = 0x04, [0x18] = 0x05, /* 11110 11010 11000 */
46 [0x08] = 0x06, [0x0a] = 0x07, [0x0e] = 0x08, /* 01000 01010 01110 */
47 [0x0f] = 0x09, [0x0d] = 0x0a, [0x0c] = 0x0b, /* 01111 01101 01100 */
48 [0x04] = 0x0c, [0x05] = 0x0d, [0x07] = 0x0e, /* 00100 00101 00111 */
49 [0x17] = 0x0f, [0x16] = 0x10, [0x06] = 0x11, /* 10111 10110 00110 */
50 [0x02] = 0x12, [0x12] = 0x13, [0x13] = 0x14, /* 00010 10010 10011 */
51 [0x1b] = 0x15, [0x0b] = 0x16, [0x03] = 0x17, /* 11011 01011 00011 */
52 [0x01] = 0x18, [0x09] = 0x19, [0x19] = 0x1a, /* 00001 01001 11001 */
53 [0x1d] = 0x1b, [0x15] = 0x1c, [0x11] = 0x1d, /* 11101 10101 10001 */
54};
55uint16_t gpio_axis_5bit_singletrack_map(
56 struct gpio_event_axis_info *info, uint16_t in)
57{
58 return gpio_axis_5bit_singletrack_map_table[in];
59}
60
61static void gpio_event_update_axis(struct gpio_axis_state *as, int report)
62{
63 struct gpio_event_axis_info *ai = as->info;
64 int i;
65 int change;
66 uint16_t state = 0;
67 uint16_t pos;
68 uint16_t old_pos = as->pos;
69 for (i = ai->count - 1; i >= 0; i--)
70 state = (state << 1) | gpio_get_value(ai->gpio[i]);
71 pos = ai->map(ai, state);
72 if (ai->flags & GPIOEAF_PRINT_RAW)
73 pr_info("axis %d-%d raw %x, pos %d -> %d\n",
74 ai->type, ai->code, state, old_pos, pos);
75 if (report && pos != old_pos) {
76 if (ai->type == EV_REL) {
77 change = (ai->decoded_size + pos - old_pos) %
78 ai->decoded_size;
79 if (change > ai->decoded_size / 2)
80 change -= ai->decoded_size;
81 if (change == ai->decoded_size / 2) {
82 if (ai->flags & GPIOEAF_PRINT_EVENT)
83 pr_info("axis %d-%d unknown direction, "
84 "pos %d -> %d\n", ai->type,
85 ai->code, old_pos, pos);
86 change = 0; /* no closest direction */
87 }
88 if (ai->flags & GPIOEAF_PRINT_EVENT)
89 pr_info("axis %d-%d change %d\n",
90 ai->type, ai->code, change);
91 input_report_rel(as->input_devs->dev[ai->dev],
92 ai->code, change);
93 } else {
94 if (ai->flags & GPIOEAF_PRINT_EVENT)
95 pr_info("axis %d-%d now %d\n",
96 ai->type, ai->code, pos);
97 input_event(as->input_devs->dev[ai->dev],
98 ai->type, ai->code, pos);
99 }
100 input_sync(as->input_devs->dev[ai->dev]);
101 }
102 as->pos = pos;
103}
104
105static irqreturn_t gpio_axis_irq_handler(int irq, void *dev_id)
106{
107 struct gpio_axis_state *as = dev_id;
108 gpio_event_update_axis(as, 1);
109 return IRQ_HANDLED;
110}
111
112int gpio_event_axis_func(struct gpio_event_input_devs *input_devs,
113 struct gpio_event_info *info, void **data, int func)
114{
115 int ret;
116 int i;
117 int irq;
118 struct gpio_event_axis_info *ai;
119 struct gpio_axis_state *as;
120
121 ai = container_of(info, struct gpio_event_axis_info, info);
122 if (func == GPIO_EVENT_FUNC_SUSPEND) {
123 for (i = 0; i < ai->count; i++)
124 disable_irq(gpio_to_irq(ai->gpio[i]));
125 return 0;
126 }
127 if (func == GPIO_EVENT_FUNC_RESUME) {
128 for (i = 0; i < ai->count; i++)
129 enable_irq(gpio_to_irq(ai->gpio[i]));
130 return 0;
131 }
132
133 if (func == GPIO_EVENT_FUNC_INIT) {
134 *data = as = kmalloc(sizeof(*as), GFP_KERNEL);
135 if (as == NULL) {
136 ret = -ENOMEM;
137 goto err_alloc_axis_state_failed;
138 }
139 as->input_devs = input_devs;
140 as->info = ai;
141 if (ai->dev >= input_devs->count) {
142 pr_err("gpio_event_axis: bad device index %d >= %d "
143 "for %d:%d\n", ai->dev, input_devs->count,
144 ai->type, ai->code);
145 ret = -EINVAL;
146 goto err_bad_device_index;
147 }
148
149 input_set_capability(input_devs->dev[ai->dev],
150 ai->type, ai->code);
151 if (ai->type == EV_ABS) {
152 input_set_abs_params(input_devs->dev[ai->dev], ai->code,
153 0, ai->decoded_size - 1, 0, 0);
154 }
155 for (i = 0; i < ai->count; i++) {
156 ret = gpio_request(ai->gpio[i], "gpio_event_axis");
157 if (ret < 0)
158 goto err_request_gpio_failed;
159 ret = gpio_direction_input(ai->gpio[i]);
160 if (ret < 0)
161 goto err_gpio_direction_input_failed;
162 ret = irq = gpio_to_irq(ai->gpio[i]);
163 if (ret < 0)
164 goto err_get_irq_num_failed;
165 ret = request_irq(irq, gpio_axis_irq_handler,
166 IRQF_TRIGGER_RISING |
167 IRQF_TRIGGER_FALLING,
168 "gpio_event_axis", as);
169 if (ret < 0)
170 goto err_request_irq_failed;
171 }
172 gpio_event_update_axis(as, 0);
173 return 0;
174 }
175
176 ret = 0;
177 as = *data;
178 for (i = ai->count - 1; i >= 0; i--) {
179 free_irq(gpio_to_irq(ai->gpio[i]), as);
180err_request_irq_failed:
181err_get_irq_num_failed:
182err_gpio_direction_input_failed:
183 gpio_free(ai->gpio[i]);
184err_request_gpio_failed:
185 ;
186 }
187err_bad_device_index:
188 kfree(as);
189 *data = NULL;
190err_alloc_axis_state_failed:
191 return ret;
192}
generated by cgit v1.2.2 (git 2.25.0) at 2026-01-02 05:36:06 -0500