drivers/tty/serial/8250/8250_fintek.c

   1 /*
   2  *  Probe for F81216A LPC to 4 UART
   3  *
   4  *  Based on drivers/tty/serial/8250_pnp.c, by Russell King, et al
   5  *
   6  *  Copyright (C) 2014 Ricardo Ribalda, Qtechnology A/S
   7  *
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License.
  12  */
  13 #include <linux/module.h>
  14 #include <linux/pci.h>
  15 #include <linux/pnp.h>
  16 #include <linux/kernel.h>
  17 #include <linux/serial_core.h>
  18 #include  "8250.h"
  19
  20 #define ADDR_PORT 0
  21 #define DATA_PORT 1
  22 #define EXIT_KEY 0xAA
  23 #define CHIP_ID1  0x20
  24 #define CHIP_ID2  0x21
  25 #define CHIP_ID_0 0x1602
  26 #define CHIP_ID_1 0x0501
  27 #define VENDOR_ID1 0x23
  28 #define VENDOR_ID1_VAL 0x19
  29 #define VENDOR_ID2 0x24
  30 #define VENDOR_ID2_VAL 0x34
  31 #define IO_ADDR1 0x61
  32 #define IO_ADDR2 0x60
  33 #define LDN 0x7
  34
  35 #define RS485  0xF0
  36 #define RTS_INVERT BIT(5)
  37 #define RS485_URA BIT(4)
  38 #define RXW4C_IRA BIT(3)
  39 #define TXW4C_IRA BIT(2)
  40
  41 #define DRIVER_NAME "8250_fintek"
  42
  43 struct fintek_8250 {
  44         u16 base_port;
  45         u8 index;
  46         u8 key;
  47         long line;
  48 };
  49
  50 static int fintek_8250_enter_key(u16 base_port, u8 key)
  51 {
  52
  53         if (!request_muxed_region(base_port, 2, DRIVER_NAME))
  54                 return -EBUSY;
  55
  56         outb(key, base_port + ADDR_PORT);
  57         outb(key, base_port + ADDR_PORT);
  58         return 0;
  59 }
  60
  61 static void fintek_8250_exit_key(u16 base_port)
  62 {
  63
  64         outb(EXIT_KEY, base_port + ADDR_PORT);
  65         release_region(base_port + ADDR_PORT, 2);
  66 }
  67
  68 static int fintek_8250_check_id(u16 base_port)
  69 {
  70         u16 chip;
  71
  72         outb(VENDOR_ID1, base_port + ADDR_PORT);
  73         if (inb(base_port + DATA_PORT) != VENDOR_ID1_VAL)
  74                 return -ENODEV;
  75
  76         outb(VENDOR_ID2, base_port + ADDR_PORT);
  77         if (inb(base_port + DATA_PORT) != VENDOR_ID2_VAL)
  78                 return -ENODEV;
  79
  80         outb(CHIP_ID1, base_port + ADDR_PORT);
  81         chip = inb(base_port + DATA_PORT);
  82         outb(CHIP_ID2, base_port + ADDR_PORT);
  83         chip |= inb(base_port + DATA_PORT) << 8;
  84
  85         if (chip != CHIP_ID_0 && chip != CHIP_ID_1)
  86                 return -ENODEV;
  87
  88         return 0;
  89 }
  90
  91 static int fintek_8250_rs485_config(struct uart_port *port,
  92                               struct serial_rs485 *rs485)
  93 {
  94         uint8_t config = 0;
  95         struct fintek_8250 *pdata = port->private_data;
  96
  97         if (!pdata)
  98                 return -EINVAL;
  99
 100         if (rs485->flags & SER_RS485_ENABLED)
 101                 memset(rs485->padding, 0, sizeof(rs485->padding));
 102         else
 103                 memset(rs485, 0, sizeof(*rs485));
 104
 105         rs485->flags &= SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND |
 106                         SER_RS485_RTS_AFTER_SEND;
 107
 108         if (rs485->delay_rts_before_send) {
 109                 rs485->delay_rts_before_send = 1;
 110                 config |= TXW4C_IRA;
 111         }
 112
 113         if (rs485->delay_rts_after_send) {
 114                 rs485->delay_rts_after_send = 1;
 115                 config |= RXW4C_IRA;
 116         }
 117
 118         if ((!!(rs485->flags & SER_RS485_RTS_ON_SEND)) ==
 119                         (!!(rs485->flags & SER_RS485_RTS_AFTER_SEND)))
 120                 rs485->flags &= SER_RS485_ENABLED;
 121         else
 122                 config |= RS485_URA;
 123
 124         if (rs485->flags & SER_RS485_RTS_ON_SEND)
 125                 config |= RTS_INVERT;
 126
 127         if (fintek_8250_enter_key(pdata->base_port, pdata->key))
 128                 return -EBUSY;
 129
 130         outb(LDN, pdata->base_port + ADDR_PORT);
 131         outb(pdata->index, pdata->base_port + DATA_PORT);
 132         outb(RS485, pdata->base_port + ADDR_PORT);
 133         outb(config, pdata->base_port + DATA_PORT);
 134         fintek_8250_exit_key(pdata->base_port);
 135
 136         port->rs485 = *rs485;
 137
 138         return 0;
 139 }
 140
 141 static int fintek_8250_base_port(u16 io_address, u8 *key, u8 *index)
 142 {
 143         static const u16 addr[] = {0x4e, 0x2e};
 144         static const u8 keys[] = {0x77, 0xa0, 0x87, 0x67};
 145         int i, j, k;
 146
 147         for (i = 0; i < ARRAY_SIZE(addr); i++) {
 148                 for (j = 0; j < ARRAY_SIZE(keys); j++) {
 149
 150                         if (fintek_8250_enter_key(addr[i], keys[j]))
 151                                 continue;
 152                         if (fintek_8250_check_id(addr[i])) {
 153                                 fintek_8250_exit_key(addr[i]);
 154                                 continue;
 155                         }
 156
 157                         for (k = 0; k < 4; k++) {
 158                                 u16 aux;
 159
 160                                 outb(LDN, addr[i] + ADDR_PORT);
 161                                 outb(k, addr[i] + DATA_PORT);
 162
 163                                 outb(IO_ADDR1, addr[i] + ADDR_PORT);
 164                                 aux = inb(addr[i] + DATA_PORT);
 165                                 outb(IO_ADDR2, addr[i] + ADDR_PORT);
 166                                 aux |= inb(addr[i] + DATA_PORT) << 8;
 167                                 if (aux != io_address)
 168                                         continue;
 169
 170                                 fintek_8250_exit_key(addr[i]);
 171                                 *key = keys[j];
 172                                 *index = k;
 173                                 return addr[i];
 174                         }
 175                         fintek_8250_exit_key(addr[i]);
 176                 }
 177         }
 178
 179         return -ENODEV;
 180 }
 181
 182 static int
 183 fintek_8250_probe(struct pnp_dev *dev, const struct pnp_device_id *dev_id)
 184 {
 185         struct uart_8250_port uart;
 186         struct fintek_8250 *pdata;
 187         int base_port;
 188         u8 key;
 189         u8 index;
 190
 191         if (!pnp_port_valid(dev, 0))
 192                 return -ENODEV;
 193
 194         base_port = fintek_8250_base_port(pnp_port_start(dev, 0), &key, &index);
 195         if (base_port < 0)
 196                 return -ENODEV;
 197
 198         memset(&uart, 0, sizeof(uart));
 199
 200         pdata = devm_kzalloc(&dev->dev, sizeof(*pdata), GFP_KERNEL);
 201         if (!pdata)
 202                 return -ENOMEM;
 203         uart.port.private_data = pdata;
 204
 205         if (!pnp_irq_valid(dev, 0))
 206                 return -ENODEV;
 207         uart.port.irq = pnp_irq(dev, 0);
 208         uart.port.iobase = pnp_port_start(dev, 0);
 209         uart.port.iotype = UPIO_PORT;
 210         uart.port.rs485_config = fintek_8250_rs485_config;
 211
 212         uart.port.flags |= UPF_SKIP_TEST | UPF_BOOT_AUTOCONF;
 213         if (pnp_irq_flags(dev, 0) & IORESOURCE_IRQ_SHAREABLE)
 214                 uart.port.flags |= UPF_SHARE_IRQ;
 215         uart.port.uartclk = 1843200;
 216         uart.port.dev = &dev->dev;
 217
 218         pdata->key = key;
 219         pdata->base_port = base_port;
 220         pdata->index = index;
 221         pdata->line = serial8250_register_8250_port(&uart);
 222         if (pdata->line < 0)
 223                 return -ENODEV;
 224
 225         pnp_set_drvdata(dev, pdata);
 226         return 0;
 227 }
 228
 229 static void fintek_8250_remove(struct pnp_dev *dev)
 230 {
 231         struct fintek_8250 *pdata = pnp_get_drvdata(dev);
 232
 233         if (pdata)
 234                 serial8250_unregister_port(pdata->line);
 235 }
 236
 237 #ifdef CONFIG_PM
 238 static int fintek_8250_suspend(struct pnp_dev *dev, pm_message_t state)
 239 {
 240         struct fintek_8250 *pdata = pnp_get_drvdata(dev);
 241
 242         if (!pdata)
 243                 return -ENODEV;
 244         serial8250_suspend_port(pdata->line);
 245         return 0;
 246 }
 247
 248 static int fintek_8250_resume(struct pnp_dev *dev)
 249 {
 250         struct fintek_8250 *pdata = pnp_get_drvdata(dev);
 251
 252         if (!pdata)
 253                 return -ENODEV;
 254         serial8250_resume_port(pdata->line);
 255         return 0;
 256 }
 257 #else
 258 #define fintek_8250_suspend NULL
 259 #define fintek_8250_resume NULL
 260 #endif /* CONFIG_PM */
 261
 262 static const struct pnp_device_id fintek_dev_table[] = {
 263         /* Qtechnology Panel PC / IO1000 */
 264         { "PNP0501"},
 265         {}
 266 };
 267
 268 MODULE_DEVICE_TABLE(pnp, fintek_dev_table);
 269
 270 static struct pnp_driver fintek_8250_driver = {
 271         .name           = DRIVER_NAME,
 272         .probe          = fintek_8250_probe,
 273         .remove         = fintek_8250_remove,
 274         .suspend        = fintek_8250_suspend,
 275         .resume         = fintek_8250_resume,
 276         .id_table       = fintek_dev_table,
 277 };
 278
 279 module_pnp_driver(fintek_8250_driver);
 280 MODULE_DESCRIPTION("Fintek F812164 module");
 281 MODULE_AUTHOR("Ricardo Ribalda <ricardo.ribalda@gmail.com>");
 282 MODULE_LICENSE("GPL");