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 
29 static 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 
71 timeout:
72 	dev_warn_ratelimited(&input->dev, "timeout polling IO memory\n");
73 }
74 
75 static 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 
129 static struct platform_driver fm07keys_driver = {
130 	.probe		= fm07keys_probe,
131 	.driver		= {
132 		.name	= DRV_NAME
133 	},
134 };
135 
136 static struct platform_device *dev;
137 
138 static 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 
149 MODULE_DEVICE_TABLE(dmi, fm07keys_dmi_table);
150 
151 static 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, -1, 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 
173 fail_register:
174 	platform_driver_unregister(&fm07keys_driver);
175 	return ret;
176 }
177 
178 static void __exit fm07keys_exit(void)
179 {
180 	platform_driver_unregister(&fm07keys_driver);
181 	platform_device_unregister(dev);
182 }
183 
184 module_init(fm07keys_init);
185 module_exit(fm07keys_exit);
186 
187 MODULE_AUTHOR("Daniel Beer <daniel.beer@tirotech.co.nz>");
188 MODULE_DESCRIPTION("Winmate FM07 front-panel keys driver");
189 MODULE_LICENSE("GPL");
190