1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Probe for F81216A LPC to 4 UART
4 *
5 * Copyright (C) 2014-2016 Ricardo Ribalda, Qtechnology A/S
6 */
7#include <linux/module.h>
8#include <linux/pci.h>
9#include <linux/pnp.h>
10#include <linux/kernel.h>
11#include <linux/serial_core.h>
12#include <linux/irq.h>
13#include "8250.h"
14
15#define ADDR_PORT 0
16#define DATA_PORT 1
17#define EXIT_KEY 0xAA
18#define CHIP_ID1 0x20
19#define CHIP_ID2 0x21
20#define CHIP_ID_F81865 0x0407
21#define CHIP_ID_F81866 0x1010
22#define CHIP_ID_F81966 0x0215
23#define CHIP_ID_F81216AD 0x1602
24#define CHIP_ID_F81216H 0x0501
25#define CHIP_ID_F81216 0x0802
26#define VENDOR_ID1 0x23
27#define VENDOR_ID1_VAL 0x19
28#define VENDOR_ID2 0x24
29#define VENDOR_ID2_VAL 0x34
30#define IO_ADDR1 0x61
31#define IO_ADDR2 0x60
32#define LDN 0x7
33
34#define FINTEK_IRQ_MODE 0x70
35#define IRQ_SHARE BIT(4)
36#define IRQ_MODE_MASK (BIT(6) | BIT(5))
37#define IRQ_LEVEL_LOW 0
38#define IRQ_EDGE_HIGH BIT(5)
39
40/*
41 * F81216H clock source register, the value and mask is the same with F81866,
42 * but it's on F0h.
43 *
44 * Clock speeds for UART (register F0h)
45 * 00: 1.8432MHz.
46 * 01: 18.432MHz.
47 * 10: 24MHz.
48 * 11: 14.769MHz.
49 */
50#define RS485 0xF0
51#define RTS_INVERT BIT(5)
52#define RS485_URA BIT(4)
53#define RXW4C_IRA BIT(3)
54#define TXW4C_IRA BIT(2)
55
56#define FIFO_CTRL 0xF6
57#define FIFO_MODE_MASK (BIT(1) | BIT(0))
58#define FIFO_MODE_128 (BIT(1) | BIT(0))
59#define RXFTHR_MODE_MASK (BIT(5) | BIT(4))
60#define RXFTHR_MODE_4X BIT(5)
61
62#define F81216_LDN_LOW 0x0
63#define F81216_LDN_HIGH 0x4
64
65/*
66 * F81866/966 registers
67 *
68 * The IRQ setting mode of F81866/966 is not the same with F81216 series.
69 * Level/Low: IRQ_MODE0:0, IRQ_MODE1:0
70 * Edge/High: IRQ_MODE0:1, IRQ_MODE1:0
71 *
72 * Clock speeds for UART (register F2h)
73 * 00: 1.8432MHz.
74 * 01: 18.432MHz.
75 * 10: 24MHz.
76 * 11: 14.769MHz.
77 */
78#define F81866_IRQ_MODE 0xf0
79#define F81866_IRQ_SHARE BIT(0)
80#define F81866_IRQ_MODE0 BIT(1)
81
82#define F81866_FIFO_CTRL FIFO_CTRL
83#define F81866_IRQ_MODE1 BIT(3)
84
85#define F81866_LDN_LOW 0x10
86#define F81866_LDN_HIGH 0x16
87
88#define F81866_UART_CLK 0xF2
89#define F81866_UART_CLK_MASK (BIT(1) | BIT(0))
90#define F81866_UART_CLK_1_8432MHZ 0
91#define F81866_UART_CLK_14_769MHZ (BIT(1) | BIT(0))
92#define F81866_UART_CLK_18_432MHZ BIT(0)
93#define F81866_UART_CLK_24MHZ BIT(1)
94
95struct fintek_8250 {
96 u16 pid;
97 u16 base_port;
98 u8 index;
99 u8 key;
100};
101
102static u8 sio_read_reg(struct fintek_8250 *pdata, u8 reg)
103{
104 outb(value: reg, port: pdata->base_port + ADDR_PORT);
105 return inb(port: pdata->base_port + DATA_PORT);
106}
107
108static void sio_write_reg(struct fintek_8250 *pdata, u8 reg, u8 data)
109{
110 outb(value: reg, port: pdata->base_port + ADDR_PORT);
111 outb(value: data, port: pdata->base_port + DATA_PORT);
112}
113
114static void sio_write_mask_reg(struct fintek_8250 *pdata, u8 reg, u8 mask,
115 u8 data)
116{
117 u8 tmp;
118
119 tmp = (sio_read_reg(pdata, reg) & ~mask) | (mask & data);
120 sio_write_reg(pdata, reg, data: tmp);
121}
122
123static int fintek_8250_enter_key(u16 base_port, u8 key)
124{
125 if (!request_muxed_region(base_port, 2, "8250_fintek"))
126 return -EBUSY;
127
128 /* Force to deactive all SuperIO in this base_port */
129 outb(EXIT_KEY, port: base_port + ADDR_PORT);
130
131 outb(value: key, port: base_port + ADDR_PORT);
132 outb(value: key, port: base_port + ADDR_PORT);
133 return 0;
134}
135
136static void fintek_8250_exit_key(u16 base_port)
137{
138
139 outb(EXIT_KEY, port: base_port + ADDR_PORT);
140 release_region(base_port + ADDR_PORT, 2);
141}
142
143static int fintek_8250_check_id(struct fintek_8250 *pdata)
144{
145 u16 chip;
146
147 if (sio_read_reg(pdata, VENDOR_ID1) != VENDOR_ID1_VAL)
148 return -ENODEV;
149
150 if (sio_read_reg(pdata, VENDOR_ID2) != VENDOR_ID2_VAL)
151 return -ENODEV;
152
153 chip = sio_read_reg(pdata, CHIP_ID1);
154 chip |= sio_read_reg(pdata, CHIP_ID2) << 8;
155
156 switch (chip) {
157 case CHIP_ID_F81865:
158 case CHIP_ID_F81866:
159 case CHIP_ID_F81966:
160 case CHIP_ID_F81216AD:
161 case CHIP_ID_F81216H:
162 case CHIP_ID_F81216:
163 break;
164 default:
165 return -ENODEV;
166 }
167
168 pdata->pid = chip;
169 return 0;
170}
171
172static int fintek_8250_get_ldn_range(struct fintek_8250 *pdata, int *min,
173 int *max)
174{
175 switch (pdata->pid) {
176 case CHIP_ID_F81966:
177 case CHIP_ID_F81865:
178 case CHIP_ID_F81866:
179 *min = F81866_LDN_LOW;
180 *max = F81866_LDN_HIGH;
181 return 0;
182
183 case CHIP_ID_F81216AD:
184 case CHIP_ID_F81216H:
185 case CHIP_ID_F81216:
186 *min = F81216_LDN_LOW;
187 *max = F81216_LDN_HIGH;
188 return 0;
189 }
190
191 return -ENODEV;
192}
193
194static int fintek_8250_rs485_config(struct uart_port *port, struct ktermios *termios,
195 struct serial_rs485 *rs485)
196{
197 uint8_t config = 0;
198 struct fintek_8250 *pdata = port->private_data;
199
200 if (!pdata)
201 return -EINVAL;
202
203
204 if (rs485->flags & SER_RS485_ENABLED) {
205 /* Hardware do not support same RTS level on send and receive */
206 if (!(rs485->flags & SER_RS485_RTS_ON_SEND) ==
207 !(rs485->flags & SER_RS485_RTS_AFTER_SEND))
208 return -EINVAL;
209 config |= RS485_URA;
210 }
211
212 if (rs485->delay_rts_before_send) {
213 rs485->delay_rts_before_send = 1;
214 config |= TXW4C_IRA;
215 }
216
217 if (rs485->delay_rts_after_send) {
218 rs485->delay_rts_after_send = 1;
219 config |= RXW4C_IRA;
220 }
221
222 if (rs485->flags & SER_RS485_RTS_ON_SEND)
223 config |= RTS_INVERT;
224
225 if (fintek_8250_enter_key(base_port: pdata->base_port, key: pdata->key))
226 return -EBUSY;
227
228 sio_write_reg(pdata, LDN, data: pdata->index);
229 sio_write_reg(pdata, RS485, data: config);
230 fintek_8250_exit_key(base_port: pdata->base_port);
231
232 return 0;
233}
234
235static void fintek_8250_set_irq_mode(struct fintek_8250 *pdata, bool is_level)
236{
237 sio_write_reg(pdata, LDN, data: pdata->index);
238
239 switch (pdata->pid) {
240 case CHIP_ID_F81966:
241 case CHIP_ID_F81866:
242 sio_write_mask_reg(pdata, F81866_FIFO_CTRL, F81866_IRQ_MODE1,
243 data: 0);
244 fallthrough;
245 case CHIP_ID_F81865:
246 sio_write_mask_reg(pdata, F81866_IRQ_MODE, F81866_IRQ_SHARE,
247 F81866_IRQ_SHARE);
248 sio_write_mask_reg(pdata, F81866_IRQ_MODE, F81866_IRQ_MODE0,
249 data: is_level ? 0 : F81866_IRQ_MODE0);
250 break;
251
252 case CHIP_ID_F81216AD:
253 case CHIP_ID_F81216H:
254 case CHIP_ID_F81216:
255 sio_write_mask_reg(pdata, FINTEK_IRQ_MODE, IRQ_SHARE,
256 IRQ_SHARE);
257 sio_write_mask_reg(pdata, FINTEK_IRQ_MODE, IRQ_MODE_MASK,
258 data: is_level ? IRQ_LEVEL_LOW : IRQ_EDGE_HIGH);
259 break;
260 }
261}
262
263static void fintek_8250_set_max_fifo(struct fintek_8250 *pdata)
264{
265 switch (pdata->pid) {
266 case CHIP_ID_F81216H: /* 128Bytes FIFO */
267 case CHIP_ID_F81966:
268 case CHIP_ID_F81866:
269 sio_write_mask_reg(pdata, FIFO_CTRL,
270 FIFO_MODE_MASK | RXFTHR_MODE_MASK,
271 FIFO_MODE_128 | RXFTHR_MODE_4X);
272 break;
273
274 default: /* Default 16Bytes FIFO */
275 break;
276 }
277}
278
279static void fintek_8250_set_termios(struct uart_port *port,
280 struct ktermios *termios,
281 const struct ktermios *old)
282{
283 struct fintek_8250 *pdata = port->private_data;
284 unsigned int baud = tty_termios_baud_rate(termios);
285 int i;
286 u8 reg;
287 static u32 baudrate_table[] = {115200, 921600, 1152000, 1500000};
288 static u8 clock_table[] = { F81866_UART_CLK_1_8432MHZ,
289 F81866_UART_CLK_14_769MHZ, F81866_UART_CLK_18_432MHZ,
290 F81866_UART_CLK_24MHZ };
291
292 /*
293 * We'll use serial8250_do_set_termios() for baud = 0, otherwise It'll
294 * crash on baudrate_table[i] % baud with "division by zero".
295 */
296 if (!baud)
297 goto exit;
298
299 switch (pdata->pid) {
300 case CHIP_ID_F81216H:
301 reg = RS485;
302 break;
303 case CHIP_ID_F81966:
304 case CHIP_ID_F81866:
305 reg = F81866_UART_CLK;
306 break;
307 default:
308 /* Don't change clocksource with unknown PID */
309 dev_warn(port->dev,
310 "%s: pid: %x Not support. use default set_termios.\n",
311 __func__, pdata->pid);
312 goto exit;
313 }
314
315 for (i = 0; i < ARRAY_SIZE(baudrate_table); ++i) {
316 if (baud > baudrate_table[i] || baudrate_table[i] % baud != 0)
317 continue;
318
319 if (port->uartclk == baudrate_table[i] * 16)
320 break;
321
322 if (fintek_8250_enter_key(base_port: pdata->base_port, key: pdata->key))
323 continue;
324
325 port->uartclk = baudrate_table[i] * 16;
326
327 sio_write_reg(pdata, LDN, data: pdata->index);
328 sio_write_mask_reg(pdata, reg, F81866_UART_CLK_MASK,
329 data: clock_table[i]);
330
331 fintek_8250_exit_key(base_port: pdata->base_port);
332 break;
333 }
334
335 if (i == ARRAY_SIZE(baudrate_table)) {
336 baud = tty_termios_baud_rate(termios: old);
337 tty_termios_encode_baud_rate(termios, ibaud: baud, obaud: baud);
338 }
339
340exit:
341 serial8250_do_set_termios(port, termios, old);
342}
343
344static void fintek_8250_set_termios_handler(struct uart_8250_port *uart)
345{
346 struct fintek_8250 *pdata = uart->port.private_data;
347
348 switch (pdata->pid) {
349 case CHIP_ID_F81216H:
350 case CHIP_ID_F81966:
351 case CHIP_ID_F81866:
352 uart->port.set_termios = fintek_8250_set_termios;
353 break;
354
355 default:
356 break;
357 }
358}
359
360static int probe_setup_port(struct fintek_8250 *pdata,
361 struct uart_8250_port *uart)
362{
363 static const u16 addr[] = {0x4e, 0x2e};
364 static const u8 keys[] = {0x77, 0xa0, 0x87, 0x67};
365 struct irq_data *irq_data;
366 bool level_mode = false;
367 int i, j, k, min, max;
368
369 for (i = 0; i < ARRAY_SIZE(addr); i++) {
370 for (j = 0; j < ARRAY_SIZE(keys); j++) {
371 pdata->base_port = addr[i];
372 pdata->key = keys[j];
373
374 if (fintek_8250_enter_key(base_port: addr[i], key: keys[j]))
375 continue;
376 if (fintek_8250_check_id(pdata) ||
377 fintek_8250_get_ldn_range(pdata, min: &min, max: &max)) {
378 fintek_8250_exit_key(base_port: addr[i]);
379 continue;
380 }
381
382 for (k = min; k < max; k++) {
383 u16 aux;
384
385 sio_write_reg(pdata, LDN, data: k);
386 aux = sio_read_reg(pdata, IO_ADDR1);
387 aux |= sio_read_reg(pdata, IO_ADDR2) << 8;
388 if (aux != uart->port.iobase)
389 continue;
390
391 pdata->index = k;
392
393 irq_data = irq_get_irq_data(irq: uart->port.irq);
394 if (irq_data)
395 level_mode =
396 irqd_is_level_type(d: irq_data);
397
398 fintek_8250_set_irq_mode(pdata, is_level: level_mode);
399 fintek_8250_set_max_fifo(pdata);
400
401 fintek_8250_exit_key(base_port: addr[i]);
402
403 return 0;
404 }
405
406 fintek_8250_exit_key(base_port: addr[i]);
407 }
408 }
409
410 return -ENODEV;
411}
412
413/* Only the first port supports delays */
414static const struct serial_rs485 fintek_8250_rs485_supported_port0 = {
415 .flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND | SER_RS485_RTS_AFTER_SEND,
416 .delay_rts_before_send = 1,
417 .delay_rts_after_send = 1,
418};
419
420static const struct serial_rs485 fintek_8250_rs485_supported = {
421 .flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND | SER_RS485_RTS_AFTER_SEND,
422};
423
424static void fintek_8250_set_rs485_handler(struct uart_8250_port *uart)
425{
426 struct fintek_8250 *pdata = uart->port.private_data;
427
428 switch (pdata->pid) {
429 case CHIP_ID_F81216AD:
430 case CHIP_ID_F81216H:
431 case CHIP_ID_F81966:
432 case CHIP_ID_F81866:
433 case CHIP_ID_F81865:
434 uart->port.rs485_config = fintek_8250_rs485_config;
435 if (!pdata->index)
436 uart->port.rs485_supported = fintek_8250_rs485_supported_port0;
437 else
438 uart->port.rs485_supported = fintek_8250_rs485_supported;
439 break;
440
441 default: /* No RS485 Auto direction functional */
442 break;
443 }
444}
445
446int fintek_8250_probe(struct uart_8250_port *uart)
447{
448 struct fintek_8250 *pdata;
449 struct fintek_8250 probe_data;
450
451 if (probe_setup_port(pdata: &probe_data, uart))
452 return -ENODEV;
453
454 pdata = devm_kzalloc(dev: uart->port.dev, size: sizeof(*pdata), GFP_KERNEL);
455 if (!pdata)
456 return -ENOMEM;
457
458 memcpy(pdata, &probe_data, sizeof(probe_data));
459 uart->port.private_data = pdata;
460 fintek_8250_set_rs485_handler(uart);
461 fintek_8250_set_termios_handler(uart);
462
463 return 0;
464}
465

source code of linux/drivers/tty/serial/8250/8250_fintek.c