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 0x4E
21#define DATA_PORT 0x4F
22#define ENTRY_KEY 0x77
23#define EXIT_KEY 0xAA
24#define CHIP_ID1  0x20
25#define CHIP_ID1_VAL 0x02
26#define CHIP_ID2  0x21
27#define CHIP_ID2_VAL 0x16
28#define VENDOR_ID1 0x23
29#define VENDOR_ID1_VAL 0x19
30#define VENDOR_ID2 0x24
31#define VENDOR_ID2_VAL 0x34
32#define LDN 0x7
33
34#define RS485  0xF0
35#define RTS_INVERT BIT(5)
36#define RS485_URA BIT(4)
37#define RXW4C_IRA BIT(3)
38#define TXW4C_IRA BIT(2)
39
40#define DRIVER_NAME "8250_fintek"
41
42static int fintek_8250_enter_key(void){
43
44	if (!request_muxed_region(ADDR_PORT, 2, DRIVER_NAME))
45		return -EBUSY;
46
47	outb(ENTRY_KEY, ADDR_PORT);
48	outb(ENTRY_KEY, ADDR_PORT);
49	return 0;
50}
51
52static void fintek_8250_exit_key(void){
53
54	outb(EXIT_KEY, ADDR_PORT);
55	release_region(ADDR_PORT, 2);
56}
57
58static int fintek_8250_get_index(resource_size_t base_addr)
59{
60	resource_size_t base[] = {0x3f8, 0x2f8, 0x3e8, 0x2e8};
61	int i;
62
63	for (i = 0; i < ARRAY_SIZE(base); i++)
64		if (base_addr == base[i])
65			return i;
66
67	return -ENODEV;
68}
69
70static int fintek_8250_check_id(void)
71{
72
73	outb(CHIP_ID1, ADDR_PORT);
74	if (inb(DATA_PORT) != CHIP_ID1_VAL)
75		return -ENODEV;
76
77	outb(CHIP_ID2, ADDR_PORT);
78	if (inb(DATA_PORT) != CHIP_ID2_VAL)
79		return -ENODEV;
80
81	outb(VENDOR_ID1, ADDR_PORT);
82	if (inb(DATA_PORT) != VENDOR_ID1_VAL)
83		return -ENODEV;
84
85	outb(VENDOR_ID2, ADDR_PORT);
86	if (inb(DATA_PORT) != VENDOR_ID2_VAL)
87		return -ENODEV;
88
89	return 0;
90}
91
92static int fintek_8250_rs485_config(struct uart_port *port,
93			      struct serial_rs485 *rs485)
94{
95	uint8_t config = 0;
96	int index = fintek_8250_get_index(port->iobase);
97
98	if (index < 0)
99		return -EINVAL;
100
101	if (rs485->flags & SER_RS485_ENABLED)
102		memset(rs485->padding, 0, sizeof(rs485->padding));
103	else
104		memset(rs485, 0, sizeof(*rs485));
105
106	rs485->flags &= SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND |
107			SER_RS485_RTS_AFTER_SEND;
108
109	if (rs485->delay_rts_before_send) {
110		rs485->delay_rts_before_send = 1;
111		config |= TXW4C_IRA;
112	}
113
114	if (rs485->delay_rts_after_send) {
115		rs485->delay_rts_after_send = 1;
116		config |= RXW4C_IRA;
117	}
118
119	if ((!!(rs485->flags & SER_RS485_RTS_ON_SEND)) ==
120			(!!(rs485->flags & SER_RS485_RTS_AFTER_SEND)))
121		rs485->flags &= SER_RS485_ENABLED;
122	else
123		config |= RS485_URA;
124
125	if (rs485->flags & SER_RS485_RTS_ON_SEND)
126		config |= RTS_INVERT;
127
128	if (fintek_8250_enter_key())
129		return -EBUSY;
130
131	outb(LDN, ADDR_PORT);
132	outb(index, DATA_PORT);
133	outb(RS485, ADDR_PORT);
134	outb(config, DATA_PORT);
135	fintek_8250_exit_key();
136
137	port->rs485 = *rs485;
138
139	return 0;
140}
141
142static int
143fintek_8250_probe(struct pnp_dev *dev, const struct pnp_device_id *dev_id)
144{
145	int line;
146	struct uart_8250_port uart;
147	int ret;
148
149	if (!pnp_port_valid(dev, 0))
150		return -ENODEV;
151
152	if (fintek_8250_get_index(pnp_port_start(dev, 0)) < 0)
153		return -ENODEV;
154
155	/* Enable configuration registers*/
156	if (fintek_8250_enter_key())
157		return -EBUSY;
158
159	/*Check ID*/
160	ret = fintek_8250_check_id();
161	fintek_8250_exit_key();
162	if (ret)
163		return ret;
164
165	memset(&uart, 0, sizeof(uart));
166	if (!pnp_irq_valid(dev, 0))
167		return -ENODEV;
168	uart.port.irq = pnp_irq(dev, 0);
169	uart.port.iobase = pnp_port_start(dev, 0);
170	uart.port.iotype = UPIO_PORT;
171	uart.port.rs485_config = fintek_8250_rs485_config;
172
173	uart.port.flags |= UPF_SKIP_TEST | UPF_BOOT_AUTOCONF;
174	if (pnp_irq_flags(dev, 0) & IORESOURCE_IRQ_SHAREABLE)
175		uart.port.flags |= UPF_SHARE_IRQ;
176	uart.port.uartclk = 1843200;
177	uart.port.dev = &dev->dev;
178
179	line = serial8250_register_8250_port(&uart);
180	if (line < 0)
181		return -ENODEV;
182
183	pnp_set_drvdata(dev, (void *)((long)line + 1));
184	return 0;
185}
186
187static void fintek_8250_remove(struct pnp_dev *dev)
188{
189	long line = (long)pnp_get_drvdata(dev);
190
191	if (line)
192		serial8250_unregister_port(line - 1);
193}
194
195#ifdef CONFIG_PM
196static int fintek_8250_suspend(struct pnp_dev *dev, pm_message_t state)
197{
198	long line = (long)pnp_get_drvdata(dev);
199
200	if (!line)
201		return -ENODEV;
202	serial8250_suspend_port(line - 1);
203	return 0;
204}
205
206static int fintek_8250_resume(struct pnp_dev *dev)
207{
208	long line = (long)pnp_get_drvdata(dev);
209
210	if (!line)
211		return -ENODEV;
212	serial8250_resume_port(line - 1);
213	return 0;
214}
215#else
216#define fintek_8250_suspend NULL
217#define fintek_8250_resume NULL
218#endif /* CONFIG_PM */
219
220static const struct pnp_device_id fintek_dev_table[] = {
221	/* Qtechnology Panel PC / IO1000 */
222	{ "PNP0501"},
223	{}
224};
225
226MODULE_DEVICE_TABLE(pnp, fintek_dev_table);
227
228static struct pnp_driver fintek_8250_driver = {
229	.name		= DRIVER_NAME,
230	.probe		= fintek_8250_probe,
231	.remove		= fintek_8250_remove,
232	.suspend	= fintek_8250_suspend,
233	.resume		= fintek_8250_resume,
234	.id_table	= fintek_dev_table,
235};
236
237module_pnp_driver(fintek_8250_driver);
238MODULE_DESCRIPTION("Fintek F812164 module");
239MODULE_AUTHOR("Ricardo Ribalda <ricardo.ribalda@gmail.com>");
240MODULE_LICENSE("GPL");
241