xref: /linux/drivers/tty/serial/8250/8250.h (revision 071bf69a0220253a44acb8b2a27f7a262b9a46bf)
1 /*
2  *  Driver for 8250/16550-type serial ports
3  *
4  *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
5  *
6  *  Copyright (C) 2001 Russell King.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  */
13 
14 #include <linux/serial_8250.h>
15 #include <linux/serial_reg.h>
16 #include <linux/dmaengine.h>
17 
18 #include "../serial_mctrl_gpio.h"
19 
20 struct uart_8250_dma {
21 	int (*tx_dma)(struct uart_8250_port *p);
22 	int (*rx_dma)(struct uart_8250_port *p);
23 
24 	/* Filter function */
25 	dma_filter_fn		fn;
26 	/* Parameter to the filter function */
27 	void			*rx_param;
28 	void			*tx_param;
29 
30 	struct dma_slave_config	rxconf;
31 	struct dma_slave_config	txconf;
32 
33 	struct dma_chan		*rxchan;
34 	struct dma_chan		*txchan;
35 
36 	dma_addr_t		rx_addr;
37 	dma_addr_t		tx_addr;
38 
39 	dma_cookie_t		rx_cookie;
40 	dma_cookie_t		tx_cookie;
41 
42 	void			*rx_buf;
43 
44 	size_t			rx_size;
45 	size_t			tx_size;
46 
47 	unsigned char		tx_running;
48 	unsigned char		tx_err;
49 	unsigned char		rx_running;
50 };
51 
52 struct old_serial_port {
53 	unsigned int uart;
54 	unsigned int baud_base;
55 	unsigned int port;
56 	unsigned int irq;
57 	upf_t        flags;
58 	unsigned char io_type;
59 	unsigned char __iomem *iomem_base;
60 	unsigned short iomem_reg_shift;
61 };
62 
63 struct serial8250_config {
64 	const char	*name;
65 	unsigned short	fifo_size;
66 	unsigned short	tx_loadsz;
67 	unsigned char	fcr;
68 	unsigned char	rxtrig_bytes[UART_FCR_R_TRIG_MAX_STATE];
69 	unsigned int	flags;
70 };
71 
72 #define UART_CAP_FIFO	(1 << 8)	/* UART has FIFO */
73 #define UART_CAP_EFR	(1 << 9)	/* UART has EFR */
74 #define UART_CAP_SLEEP	(1 << 10)	/* UART has IER sleep */
75 #define UART_CAP_AFE	(1 << 11)	/* MCR-based hw flow control */
76 #define UART_CAP_UUE	(1 << 12)	/* UART needs IER bit 6 set (Xscale) */
77 #define UART_CAP_RTOIE	(1 << 13)	/* UART needs IER bit 4 set (Xscale, Tegra) */
78 #define UART_CAP_HFIFO	(1 << 14)	/* UART has a "hidden" FIFO */
79 #define UART_CAP_RPM	(1 << 15)	/* Runtime PM is active while idle */
80 
81 #define UART_BUG_QUOT	(1 << 0)	/* UART has buggy quot LSB */
82 #define UART_BUG_TXEN	(1 << 1)	/* UART has buggy TX IIR status */
83 #define UART_BUG_NOMSR	(1 << 2)	/* UART has buggy MSR status bits (Au1x00) */
84 #define UART_BUG_THRE	(1 << 3)	/* UART has buggy THRE reassertion */
85 #define UART_BUG_PARITY	(1 << 4)	/* UART mishandles parity if FIFO enabled */
86 
87 
88 #ifdef CONFIG_SERIAL_8250_SHARE_IRQ
89 #define SERIAL8250_SHARE_IRQS 1
90 #else
91 #define SERIAL8250_SHARE_IRQS 0
92 #endif
93 
94 #define SERIAL8250_PORT_FLAGS(_base, _irq, _flags)		\
95 	{							\
96 		.iobase		= _base,			\
97 		.irq		= _irq,				\
98 		.uartclk	= 1843200,			\
99 		.iotype		= UPIO_PORT,			\
100 		.flags		= UPF_BOOT_AUTOCONF | (_flags),	\
101 	}
102 
103 #define SERIAL8250_PORT(_base, _irq) SERIAL8250_PORT_FLAGS(_base, _irq, 0)
104 
105 
106 static inline int serial_in(struct uart_8250_port *up, int offset)
107 {
108 	return up->port.serial_in(&up->port, offset);
109 }
110 
111 static inline void serial_out(struct uart_8250_port *up, int offset, int value)
112 {
113 	up->port.serial_out(&up->port, offset, value);
114 }
115 
116 void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p);
117 
118 static inline int serial_dl_read(struct uart_8250_port *up)
119 {
120 	return up->dl_read(up);
121 }
122 
123 static inline void serial_dl_write(struct uart_8250_port *up, int value)
124 {
125 	up->dl_write(up, value);
126 }
127 
128 struct uart_8250_port *serial8250_get_port(int line);
129 void serial8250_rpm_get(struct uart_8250_port *p);
130 void serial8250_rpm_put(struct uart_8250_port *p);
131 int serial8250_em485_init(struct uart_8250_port *p);
132 void serial8250_em485_destroy(struct uart_8250_port *p);
133 
134 static inline void serial8250_out_MCR(struct uart_8250_port *up, int value)
135 {
136 	int mctrl_gpio = 0;
137 
138 	serial_out(up, UART_MCR, value);
139 
140 	if (value & UART_MCR_RTS)
141 		mctrl_gpio |= TIOCM_RTS;
142 	if (value & UART_MCR_DTR)
143 		mctrl_gpio |= TIOCM_DTR;
144 
145 	mctrl_gpio_set(up->gpios, mctrl_gpio);
146 }
147 
148 static inline int serial8250_in_MCR(struct uart_8250_port *up)
149 {
150 	int mctrl, mctrl_gpio = 0;
151 
152 	mctrl = serial_in(up, UART_MCR);
153 
154 	/* save current MCR values */
155 	if (mctrl & UART_MCR_RTS)
156 		mctrl_gpio |= TIOCM_RTS;
157 	if (mctrl & UART_MCR_DTR)
158 		mctrl_gpio |= TIOCM_DTR;
159 
160 	mctrl_gpio = mctrl_gpio_get_outputs(up->gpios, &mctrl_gpio);
161 
162 	if (mctrl_gpio & TIOCM_RTS)
163 		mctrl |= UART_MCR_RTS;
164 	else
165 		mctrl &= ~UART_MCR_RTS;
166 
167 	if (mctrl_gpio & TIOCM_DTR)
168 		mctrl |= UART_MCR_DTR;
169 	else
170 		mctrl &= ~UART_MCR_DTR;
171 
172 	return mctrl;
173 }
174 
175 #if defined(__alpha__) && !defined(CONFIG_PCI)
176 /*
177  * Digital did something really horribly wrong with the OUT1 and OUT2
178  * lines on at least some ALPHA's.  The failure mode is that if either
179  * is cleared, the machine locks up with endless interrupts.
180  */
181 #define ALPHA_KLUDGE_MCR  (UART_MCR_OUT2 | UART_MCR_OUT1)
182 #else
183 #define ALPHA_KLUDGE_MCR 0
184 #endif
185 
186 #ifdef CONFIG_SERIAL_8250_PNP
187 int serial8250_pnp_init(void);
188 void serial8250_pnp_exit(void);
189 #else
190 static inline int serial8250_pnp_init(void) { return 0; }
191 static inline void serial8250_pnp_exit(void) { }
192 #endif
193 
194 #ifdef CONFIG_SERIAL_8250_FINTEK
195 int fintek_8250_probe(struct uart_8250_port *uart);
196 #else
197 static inline int fintek_8250_probe(struct uart_8250_port *uart) { return 0; }
198 #endif
199 
200 #ifdef CONFIG_ARCH_OMAP1
201 static inline int is_omap1_8250(struct uart_8250_port *pt)
202 {
203 	int res;
204 
205 	switch (pt->port.mapbase) {
206 	case OMAP1_UART1_BASE:
207 	case OMAP1_UART2_BASE:
208 	case OMAP1_UART3_BASE:
209 		res = 1;
210 		break;
211 	default:
212 		res = 0;
213 		break;
214 	}
215 
216 	return res;
217 }
218 
219 static inline int is_omap1510_8250(struct uart_8250_port *pt)
220 {
221 	if (!cpu_is_omap1510())
222 		return 0;
223 
224 	return is_omap1_8250(pt);
225 }
226 #else
227 static inline int is_omap1_8250(struct uart_8250_port *pt)
228 {
229 	return 0;
230 }
231 static inline int is_omap1510_8250(struct uart_8250_port *pt)
232 {
233 	return 0;
234 }
235 #endif
236 
237 #ifdef CONFIG_SERIAL_8250_DMA
238 extern int serial8250_tx_dma(struct uart_8250_port *);
239 extern int serial8250_rx_dma(struct uart_8250_port *);
240 extern void serial8250_rx_dma_flush(struct uart_8250_port *);
241 extern int serial8250_request_dma(struct uart_8250_port *);
242 extern void serial8250_release_dma(struct uart_8250_port *);
243 #else
244 static inline int serial8250_tx_dma(struct uart_8250_port *p)
245 {
246 	return -1;
247 }
248 static inline int serial8250_rx_dma(struct uart_8250_port *p)
249 {
250 	return -1;
251 }
252 static inline void serial8250_rx_dma_flush(struct uart_8250_port *p) { }
253 static inline int serial8250_request_dma(struct uart_8250_port *p)
254 {
255 	return -1;
256 }
257 static inline void serial8250_release_dma(struct uart_8250_port *p) { }
258 #endif
259 
260 static inline int ns16550a_goto_highspeed(struct uart_8250_port *up)
261 {
262 	unsigned char status;
263 
264 	status = serial_in(up, 0x04); /* EXCR2 */
265 #define PRESL(x) ((x) & 0x30)
266 	if (PRESL(status) == 0x10) {
267 		/* already in high speed mode */
268 		return 0;
269 	} else {
270 		status &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */
271 		status |= 0x10;  /* 1.625 divisor for baud_base --> 921600 */
272 		serial_out(up, 0x04, status);
273 	}
274 	return 1;
275 }
276 
277 static inline int serial_index(struct uart_port *port)
278 {
279 	return port->minor - 64;
280 }
281