drivers/platform/x86/winmate-fm07-keys.c

   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, 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
 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");