tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#include <linux/interrupt.h>
2#include <linux/ioport.h>
3
4#include "spk_types.h"
5#include "speakup.h"
6#include "spk_priv.h"
7#include "serialio.h"
8
9#include <linux/serial_core.h>
10/* WARNING: Do not change this to <linux/serial.h> without testing that
11 * SERIAL_PORT_DFNS does get defined to the appropriate value.
12 */
13#include <asm/serial.h>
14
15#ifndef SERIAL_PORT_DFNS
16#define SERIAL_PORT_DFNS
17#endif
18
19static void start_serial_interrupt(int irq);
20
21static const struct old_serial_port rs_table[] = {
22 SERIAL_PORT_DFNS
23};
24static const struct old_serial_port *serstate;
25static int timeouts;
26
27const struct old_serial_port *spk_serial_init(int index)
28{
29 int baud = 9600, quot = 0;
30 unsigned int cval = 0;
31 int cflag = CREAD | HUPCL | CLOCAL | B9600 | CS8;
32 const struct old_serial_port *ser;
33 int err;
34
35 if (index >= ARRAY_SIZE(rs_table)) {
36 pr_info("no port info for ttyS%d\n", index);
37 return NULL;
38 }
39 ser = rs_table + index;
40
41 /* Divisor, bytesize and parity */
42 quot = ser->baud_base / baud;
43 cval = cflag & (CSIZE | CSTOPB);
44#if defined(__powerpc__) || defined(__alpha__)
45 cval >>= 8;
46#else /* !__powerpc__ && !__alpha__ */
47 cval >>= 4;
48#endif /* !__powerpc__ && !__alpha__ */
49 if (cflag & PARENB)
50 cval |= UART_LCR_PARITY;
51 if (!(cflag & PARODD))
52 cval |= UART_LCR_EPAR;
53 if (synth_request_region(ser->port, 8)) {
54 /* try to take it back. */
55 pr_info("Ports not available, trying to steal them\n");
56 __release_region(&ioport_resource, ser->port, 8);
57 err = synth_request_region(ser->port, 8);
58 if (err) {
59 pr_warn("Unable to allocate port at %x, errno %i",
60 ser->port, err);
61 return NULL;
62 }
63 }
64
65 /* Disable UART interrupts, set DTR and RTS high
66 * and set speed.
67 */
68 outb(cval | UART_LCR_DLAB, ser->port + UART_LCR); /* set DLAB */
69 outb(quot & 0xff, ser->port + UART_DLL); /* LS of divisor */
70 outb(quot >> 8, ser->port + UART_DLM); /* MS of divisor */
71 outb(cval, ser->port + UART_LCR); /* reset DLAB */
72
73 /* Turn off Interrupts */
74 outb(0, ser->port + UART_IER);
75 outb(UART_MCR_DTR | UART_MCR_RTS, ser->port + UART_MCR);
76
77 /* If we read 0xff from the LSR, there is no UART here. */
78 if (inb(ser->port + UART_LSR) == 0xff) {
79 synth_release_region(ser->port, 8);
80 serstate = NULL;
81 return NULL;
82 }
83
84 mdelay(1);
85 speakup_info.port_tts = ser->port;
86 serstate = ser;
87
88 start_serial_interrupt(ser->irq);
89
90 return ser;
91}
92
93static irqreturn_t synth_readbuf_handler(int irq, void *dev_id)
94{
95 unsigned long flags;
96 int c;
97
98 spin_lock_irqsave(&speakup_info.spinlock, flags);
99 while (inb_p(speakup_info.port_tts + UART_LSR) & UART_LSR_DR) {
100
101 c = inb_p(speakup_info.port_tts+UART_RX);
102 synth->read_buff_add((u_char)c);
103 }
104 spin_unlock_irqrestore(&speakup_info.spinlock, flags);
105 return IRQ_HANDLED;
106}
107
108static void start_serial_interrupt(int irq)
109{
110 int rv;
111
112 if (!synth->read_buff_add)
113 return;
114
115 rv = request_irq(irq, synth_readbuf_handler, IRQF_SHARED,
116 "serial", (void *)synth_readbuf_handler);
117
118 if (rv)
119 pr_err("Unable to request Speakup serial I R Q\n");
120 /* Set MCR */
121 outb(UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2,
122 speakup_info.port_tts + UART_MCR);
123 /* Turn on Interrupts */
124 outb(UART_IER_MSI|UART_IER_RLSI|UART_IER_RDI,
125 speakup_info.port_tts + UART_IER);
126 inb(speakup_info.port_tts+UART_LSR);
127 inb(speakup_info.port_tts+UART_RX);
128 inb(speakup_info.port_tts+UART_IIR);
129 inb(speakup_info.port_tts+UART_MSR);
130 outb(1, speakup_info.port_tts + UART_FCR); /* Turn FIFO On */
131}
132
133void spk_stop_serial_interrupt(void)
134{
135 if (speakup_info.port_tts == 0)
136 return;
137
138 if (!synth->read_buff_add)
139 return;
140
141 /* Turn off interrupts */
142 outb(0, speakup_info.port_tts+UART_IER);
143 /* Free IRQ */
144 free_irq(serstate->irq, (void *)synth_readbuf_handler);
145}
146
147int spk_wait_for_xmitr(void)
148{
149 int tmout = SPK_XMITR_TIMEOUT;
150
151 if ((synth->alive) && (timeouts >= NUM_DISABLE_TIMEOUTS)) {
152 pr_warn("%s: too many timeouts, deactivating speakup\n",
153 synth->long_name);
154 synth->alive = 0;
155 /* No synth any more, so nobody will restart TTYs, and we thus
156 * need to do it ourselves. Now that there is no synth we can
157 * let application flood anyway
158 */
159 speakup_start_ttys();
160 timeouts = 0;
161 return 0;
162 }
163 while (spk_serial_tx_busy()) {
164 if (--tmout == 0) {
165 pr_warn("%s: timed out (tx busy)\n", synth->long_name);
166 timeouts++;
167 return 0;
168 }
169 udelay(1);
170 }
171 tmout = SPK_CTS_TIMEOUT;
172 while (!((inb_p(speakup_info.port_tts + UART_MSR)) & UART_MSR_CTS)) {
173 /* CTS */
174 if (--tmout == 0) {
175 timeouts++;
176 return 0;
177 }
178 udelay(1);
179 }
180 timeouts = 0;
181 return 1;
182}
183
184unsigned char spk_serial_in(void)
185{
186 int tmout = SPK_SERIAL_TIMEOUT;
187
188 while (!(inb_p(speakup_info.port_tts + UART_LSR) & UART_LSR_DR)) {
189 if (--tmout == 0) {
190 pr_warn("time out while waiting for input.\n");
191 return 0xff;
192 }
193 udelay(1);
194 }
195 return inb_p(speakup_info.port_tts + UART_RX);
196}
197EXPORT_SYMBOL_GPL(spk_serial_in);
198
199unsigned char spk_serial_in_nowait(void)
200{
201 unsigned char lsr;
202
203 lsr = inb_p(speakup_info.port_tts + UART_LSR);
204 if (!(lsr & UART_LSR_DR))
205 return 0;
206 return inb_p(speakup_info.port_tts + UART_RX);
207}
208EXPORT_SYMBOL_GPL(spk_serial_in_nowait);
209
210int spk_serial_out(const char ch)
211{
212 if (synth->alive && spk_wait_for_xmitr()) {
213 outb_p(ch, speakup_info.port_tts);
214 return 1;
215 }
216 return 0;
217}
218EXPORT_SYMBOL_GPL(spk_serial_out);
219
220void spk_serial_release(void)
221{
222 if (speakup_info.port_tts == 0)
223 return;
224 synth_release_region(speakup_info.port_tts, 8);
225 speakup_info.port_tts = 0;
226}
227EXPORT_SYMBOL_GPL(spk_serial_release);