1// SPDX-License-Identifier: GPL-2.0
2//
3// Driver for the Winmate FM07 front-panel keys
4//
5// Author: Daniel Beer <daniel.beer@tirotech.co.nz>
6
7#include <linux/init.h>
8#include <linux/module.h>
9#include <linux/input.h>
10#include <linux/ioport.h>
11#include <linux/platform_device.h>
12#include <linux/dmi.h>
13#include <linux/io.h>
14
15#define DRV_NAME	"winmate-fm07keys"
16
17#define PORT_CMD	0x6c
18#define PORT_DATA	0x68
19
20#define EC_ADDR_KEYS	0x3b
21#define EC_CMD_READ	0x80
22
23#define BASE_KEY	KEY_F13
24#define NUM_KEYS	5
25
26/* Typically we're done in fewer than 10 iterations */
27#define LOOP_TIMEOUT	1000
28
29static void fm07keys_poll(struct input_dev *input)
30{
31	uint8_t k;
32	int i;
33
34	/* Flush output buffer */
35	i = 0;
36	while (inb(PORT_CMD) & 0x01) {
37		if (++i >= LOOP_TIMEOUT)
38			goto timeout;
39		inb(PORT_DATA);
40	}
41
42	/* Send request and wait for write completion */
43	outb(EC_CMD_READ, PORT_CMD);
44	i = 0;
45	while (inb(PORT_CMD) & 0x02)
46		if (++i >= LOOP_TIMEOUT)
47			goto timeout;
48
49	outb(EC_ADDR_KEYS, PORT_DATA);
50	i = 0;
51	while (inb(PORT_CMD) & 0x02)
52		if (++i >= LOOP_TIMEOUT)
53			goto timeout;
54
55	/* Wait for data ready */
56	i = 0;
57	while (!(inb(PORT_CMD) & 0x01))
58		if (++i >= LOOP_TIMEOUT)
59			goto timeout;
60	k = inb(PORT_DATA);
61
62	/* Notify of new key states */
63	for (i = 0; i < NUM_KEYS; i++) {
64		input_report_key(input, BASE_KEY + i, (~k) & 1);
65		k >>= 1;
66	}
67
68	input_sync(input);
69	return;
70
71timeout:
72	dev_warn_ratelimited(&input->dev, "timeout polling IO memory\n");
73}
74
75static int fm07keys_probe(struct platform_device *pdev)
76{
77	struct device *dev = &pdev->dev;
78	struct input_dev *input;
79	int ret;
80	int i;
81
82	input = devm_input_allocate_device(dev);
83	if (!input) {
84		dev_err(dev, "no memory for input device\n");
85		return -ENOMEM;
86	}
87
88	if (!devm_request_region(dev, PORT_CMD, 1, "Winmate FM07 EC"))
89		return -EBUSY;
90	if (!devm_request_region(dev, PORT_DATA, 1, "Winmate FM07 EC"))
91		return -EBUSY;
92
93	input->name = "Winmate FM07 front-panel keys";
94	input->phys = DRV_NAME "/input0";
95
96	input->id.bustype = BUS_HOST;
97	input->id.vendor = 0x0001;
98	input->id.product = 0x0001;
99	input->id.version = 0x0100;
100
101	__set_bit(EV_KEY, input->evbit);
102
103	for (i = 0; i < NUM_KEYS; i++)
104		__set_bit(BASE_KEY + i, input->keybit);
105
106	ret = input_setup_polling(input, fm07keys_poll);
107	if (ret) {
108		dev_err(dev, "unable to set up polling, err=%d\n", ret);
109		return ret;
110	}
111
112	/* These are silicone buttons. They can't be pressed in rapid
113	 * succession too quickly, and 50 Hz seems to be an adequate
114	 * sampling rate without missing any events when tested.
115	 */
116	input_set_poll_interval(input, 20);
117
118	ret = input_register_device(input);
119	if (ret) {
120		dev_err(dev, "unable to register polled device, err=%d\n",
121			ret);
122		return ret;
123	}
124
125	input_sync(input);
126	return 0;
127}
128
129static struct platform_driver fm07keys_driver = {
130	.probe		= fm07keys_probe,
131	.driver		= {
132		.name	= DRV_NAME
133	},
134};
135
136static struct platform_device *dev;
137
138static const struct dmi_system_id fm07keys_dmi_table[] __initconst = {
139	{
140		/* FM07 and FM07P */
141		.matches = {
142			DMI_MATCH(DMI_SYS_VENDOR, "Winmate Inc."),
143			DMI_MATCH(DMI_PRODUCT_NAME, "IP30"),
144		},
145	},
146	{ }
147};
148
149MODULE_DEVICE_TABLE(dmi, fm07keys_dmi_table);
150
151static int __init fm07keys_init(void)
152{
153	int ret;
154
155	if (!dmi_check_system(fm07keys_dmi_table))
156		return -ENODEV;
157
158	ret = platform_driver_register(&fm07keys_driver);
159	if (ret) {
160		pr_err("fm07keys: failed to register driver, err=%d\n", ret);
161		return ret;
162	}
163
164	dev = platform_device_register_simple(DRV_NAME, PLATFORM_DEVID_NONE, NULL, 0);
165	if (IS_ERR(dev)) {
166		ret = PTR_ERR(dev);
167		pr_err("fm07keys: failed to allocate device, err = %d\n", ret);
168		goto fail_register;
169	}
170
171	return 0;
172
173fail_register:
174	platform_driver_unregister(&fm07keys_driver);
175	return ret;
176}
177
178static void __exit fm07keys_exit(void)
179{
180	platform_driver_unregister(&fm07keys_driver);
181	platform_device_unregister(dev);
182}
183
184module_init(fm07keys_init);
185module_exit(fm07keys_exit);
186
187MODULE_AUTHOR("Daniel Beer <daniel.beer@tirotech.co.nz>");
188MODULE_DESCRIPTION("Winmate FM07 front-panel keys driver");
189MODULE_LICENSE("GPL");
190