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
fintek_8250_enter_key(u16 base_port,u8 key)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
fintek_8250_exit_key(u16 base_port)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
fintek_8250_check_id(u16 base_port)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
fintek_8250_rs485_config(struct uart_port * port,struct serial_rs485 * rs485)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
fintek_8250_base_port(u16 io_address,u8 * key,u8 * index)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
fintek_8250_probe(struct pnp_dev * dev,const struct pnp_device_id * dev_id)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
fintek_8250_remove(struct pnp_dev * dev)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
fintek_8250_suspend(struct pnp_dev * dev,pm_message_t state)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
fintek_8250_resume(struct pnp_dev * dev)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");
283