sandbox: serial: Support a coloured console
[karo-tx-uboot.git] / drivers / serial / sandbox.c
1 /*
2  * Copyright (c) 2011 The Chromium OS Authors.
3  *
4  * SPDX-License-Identifier:     GPL-2.0+
5  */
6
7 /*
8  * This provide a test serial port. It provides an emulated serial port where
9  * a test program and read out the serial output and inject serial input for
10  * U-Boot.
11  */
12
13 #include <common.h>
14 #include <dm.h>
15 #include <fdtdec.h>
16 #include <lcd.h>
17 #include <os.h>
18 #include <serial.h>
19 #include <linux/compiler.h>
20 #include <asm/state.h>
21
22 DECLARE_GLOBAL_DATA_PTR;
23
24 /*
25  *
26  *   serial_buf: A buffer that holds keyboard characters for the
27  *               Sandbox U-boot.
28  *
29  * invariants:
30  *   serial_buf_write            == serial_buf_read -> empty buffer
31  *   (serial_buf_write + 1) % 16 == serial_buf_read -> full buffer
32  */
33 static char serial_buf[16];
34 static unsigned int serial_buf_write;
35 static unsigned int serial_buf_read;
36
37 struct sandbox_serial_platdata {
38         int colour;     /* Text colour to use for output, -1 for none */
39 };
40
41 struct sandbox_serial_priv {
42         bool start_of_line;
43 };
44
45 /**
46  * output_ansi_colour() - Output an ANSI colour code
47  *
48  * @colour: Colour to output (0-7)
49  */
50 static void output_ansi_colour(int colour)
51 {
52         char ansi_code[] = "\x1b[1;3Xm";
53
54         ansi_code[5] = '0' + colour;
55         os_write(1, ansi_code, sizeof(ansi_code) - 1);
56 }
57
58 static void output_ansi_reset(void)
59 {
60         os_write(1, "\x1b[0m", 4);
61 }
62
63 static int sandbox_serial_probe(struct udevice *dev)
64 {
65         struct sandbox_state *state = state_get_current();
66         struct sandbox_serial_priv *priv = dev_get_priv(dev);
67
68         if (state->term_raw != STATE_TERM_COOKED)
69                 os_tty_raw(0, state->term_raw == STATE_TERM_RAW_WITH_SIGS);
70         priv->start_of_line = 0;
71
72         return 0;
73 }
74
75 static int sandbox_serial_remove(struct udevice *dev)
76 {
77         struct sandbox_serial_platdata *plat = dev->platdata;
78
79         if (plat->colour != -1)
80                 output_ansi_reset();
81
82         return 0;
83 }
84
85 static int sandbox_serial_putc(struct udevice *dev, const char ch)
86 {
87         struct sandbox_serial_priv *priv = dev_get_priv(dev);
88         struct sandbox_serial_platdata *plat = dev->platdata;
89
90         if (priv->start_of_line && plat->colour != -1) {
91                 priv->start_of_line = false;
92                 output_ansi_colour(plat->colour);
93         }
94
95         os_write(1, &ch, 1);
96         if (ch == '\n')
97                 priv->start_of_line = true;
98
99         return 0;
100 }
101
102 static unsigned int increment_buffer_index(unsigned int index)
103 {
104         return (index + 1) % ARRAY_SIZE(serial_buf);
105 }
106
107 static int sandbox_serial_pending(struct udevice *dev, bool input)
108 {
109         const unsigned int next_index =
110                 increment_buffer_index(serial_buf_write);
111         ssize_t count;
112
113         if (!input)
114                 return 0;
115
116         os_usleep(100);
117 #ifdef CONFIG_LCD
118         lcd_sync();
119 #endif
120         if (next_index == serial_buf_read)
121                 return 1;       /* buffer full */
122
123         count = os_read_no_block(0, &serial_buf[serial_buf_write], 1);
124         if (count == 1)
125                 serial_buf_write = next_index;
126
127         return serial_buf_write != serial_buf_read;
128 }
129
130 static int sandbox_serial_getc(struct udevice *dev)
131 {
132         int result;
133
134         if (!sandbox_serial_pending(dev, true))
135                 return -EAGAIN; /* buffer empty */
136
137         result = serial_buf[serial_buf_read];
138         serial_buf_read = increment_buffer_index(serial_buf_read);
139         return result;
140 }
141
142 static const char * const ansi_colour[] = {
143         "black", "red", "green", "yellow", "blue", "megenta", "cyan",
144         "white",
145 };
146
147 static int sandbox_serial_ofdata_to_platdata(struct udevice *dev)
148 {
149         struct sandbox_serial_platdata *plat = dev->platdata;
150         const char *colour;
151         int i;
152
153         plat->colour = -1;
154         colour = fdt_getprop(gd->fdt_blob, dev->of_offset,
155                              "sandbox,text-colour", NULL);
156         if (colour) {
157                 for (i = 0; i < ARRAY_SIZE(ansi_colour); i++) {
158                         if (!strcmp(colour, ansi_colour[i])) {
159                                 plat->colour = i;
160                                 break;
161                         }
162                 }
163         }
164
165         return 0;
166 }
167
168 static const struct dm_serial_ops sandbox_serial_ops = {
169         .putc = sandbox_serial_putc,
170         .pending = sandbox_serial_pending,
171         .getc = sandbox_serial_getc,
172 };
173
174 static const struct udevice_id sandbox_serial_ids[] = {
175         { .compatible = "sandbox,serial" },
176         { }
177 };
178
179 U_BOOT_DRIVER(serial_sandbox) = {
180         .name   = "serial_sandbox",
181         .id     = UCLASS_SERIAL,
182         .of_match = sandbox_serial_ids,
183         .ofdata_to_platdata = sandbox_serial_ofdata_to_platdata,
184         .platdata_auto_alloc_size = sizeof(struct sandbox_serial_platdata),
185         .priv_auto_alloc_size = sizeof(struct sandbox_serial_priv),
186         .probe = sandbox_serial_probe,
187         .remove = sandbox_serial_remove,
188         .ops    = &sandbox_serial_ops,
189         .flags = DM_FLAG_PRE_RELOC,
190 };
191
192 static const struct sandbox_serial_platdata platdata_non_fdt = {
193         .colour = -1,
194 };
195
196 U_BOOT_DEVICE(serial_sandbox_non_fdt) = {
197         .name = "serial_sandbox",
198         .platdata = &platdata_non_fdt,
199 };