summaryrefslogtreecommitdiff
path: root/drivers/serial/serial-uclass.c
blob: d04104e74700108bf1df0cc232481336c6db1259 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
/*
 * Copyright (c) 2014 The Chromium OS Authors.
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <dm.h>
#include <errno.h>
#include <fdtdec.h>
#include <os.h>
#include <serial.h>
#include <stdio_dev.h>
#include <dm/lists.h>
#include <dm/device-internal.h>

DECLARE_GLOBAL_DATA_PTR;

/* The currently-selected console serial device */
struct udevice *cur_dev __attribute__ ((section(".data")));

#ifndef CONFIG_SYS_MALLOC_F_LEN
#error "Serial is required before relocation - define CONFIG_SYS_MALLOC_F_LEN to make this work"
#endif

static void serial_find_console_or_panic(void)
{
	int node;

	/* Check for a chosen console */
	node = fdtdec_get_chosen_node(gd->fdt_blob, "stdout-path");
	if (node < 0)
		node = fdtdec_get_alias_node(gd->fdt_blob, "console");
	if (!uclass_get_device_by_of_offset(UCLASS_SERIAL, node, &cur_dev))
		return;

	/*
	 * If the console is not marked to be bound before relocation, bind
	 * it anyway.
	 */
	if (node > 0 &&
	    !lists_bind_fdt(gd->dm_root, gd->fdt_blob, node, &cur_dev)) {
		if (!device_probe(cur_dev))
			return;
		cur_dev = NULL;
	}

	/*
	 * Failing that, get the device with sequence number 0, or in extremis
	 * just the first serial device we can find. But we insist on having
	 * a console (even if it is silent).
	 */
	if (uclass_get_device_by_seq(UCLASS_SERIAL, 0, &cur_dev) &&
	    (uclass_first_device(UCLASS_SERIAL, &cur_dev) || !cur_dev))
		panic("No serial driver found");
}

/* Called prior to relocation */
int serial_init(void)
{
	serial_find_console_or_panic();
	gd->flags |= GD_FLG_SERIAL_READY;

	return 0;
}

/* Called after relocation */
void serial_initialize(void)
{
	serial_find_console_or_panic();
}

void serial_putc(char ch)
{
	struct dm_serial_ops *ops = serial_get_ops(cur_dev);
	int err;

	do {
		err = ops->putc(cur_dev, ch);
	} while (err == -EAGAIN);
	if (ch == '\n')
		serial_putc('\r');
}

void serial_setbrg(void)
{
	struct dm_serial_ops *ops = serial_get_ops(cur_dev);

	if (ops->setbrg)
		ops->setbrg(cur_dev, gd->baudrate);
}

void serial_puts(const char *str)
{
	while (*str)
		serial_putc(*str++);
}

int serial_tstc(void)
{
	struct dm_serial_ops *ops = serial_get_ops(cur_dev);

	if (ops->pending)
		return ops->pending(cur_dev, true);

	return 1;
}

int serial_getc(void)
{
	struct dm_serial_ops *ops = serial_get_ops(cur_dev);
	int err;

	do {
		err = ops->getc(cur_dev);
	} while (err == -EAGAIN);

	return err >= 0 ? err : 0;
}

void serial_stdio_init(void)
{
}

void serial_stub_putc(struct stdio_dev *sdev, const char ch)
{
	struct udevice *dev = sdev->priv;
	struct dm_serial_ops *ops = serial_get_ops(dev);

	ops->putc(dev, ch);
}

void serial_stub_puts(struct stdio_dev *sdev, const char *str)
{
	while (*str)
		serial_stub_putc(sdev, *str++);
}

int serial_stub_getc(struct stdio_dev *sdev)
{
	struct udevice *dev = sdev->priv;
	struct dm_serial_ops *ops = serial_get_ops(dev);

	int err;

	do {
		err = ops->getc(dev);
	} while (err == -EAGAIN);

	return err >= 0 ? err : 0;
}

int serial_stub_tstc(struct stdio_dev *sdev)
{
	struct udevice *dev = sdev->priv;
	struct dm_serial_ops *ops = serial_get_ops(dev);

	if (ops->pending)
		return ops->pending(dev, true);

	return 1;
}

static int serial_post_probe(struct udevice *dev)
{
	struct stdio_dev sdev;
	struct dm_serial_ops *ops = serial_get_ops(dev);
	struct serial_dev_priv *upriv = dev->uclass_priv;
	int ret;

	/* Set the baud rate */
	if (ops->setbrg) {
		ret = ops->setbrg(dev, gd->baudrate);
		if (ret)
			return ret;
	}

	if (!(gd->flags & GD_FLG_RELOC))
		return 0;

	memset(&sdev, '\0', sizeof(sdev));

	strncpy(sdev.name, dev->name, sizeof(sdev.name));
	sdev.flags = DEV_FLAGS_OUTPUT | DEV_FLAGS_INPUT;
	sdev.priv = dev;
	sdev.putc = serial_stub_putc;
	sdev.puts = serial_stub_puts;
	sdev.getc = serial_stub_getc;
	sdev.tstc = serial_stub_tstc;
	stdio_register_dev(&sdev, &upriv->sdev);

	return 0;
}

static int serial_pre_remove(struct udevice *dev)
{
#ifdef CONFIG_SYS_STDIO_DEREGISTER
	struct serial_dev_priv *upriv = dev->uclass_priv;

	if (stdio_deregister_dev(upriv->sdev))
		return -EPERM;
#endif

	return 0;
}

UCLASS_DRIVER(serial) = {
	.id		= UCLASS_SERIAL,
	.name		= "serial",
	.post_probe	= serial_post_probe,
	.pre_remove	= serial_pre_remove,
	.per_device_auto_alloc_size = sizeof(struct serial_dev_priv),
};