1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright 2017 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
4 */
5
6 #include <linux/delay.h>
7 #include <linux/slab.h>
8 #include <linux/sched/types.h>
9
10 #include <media/cec-pin.h>
11 #include "cec-pin-priv.h"
12
13 struct cec_error_inj_cmd {
14 unsigned int mode_offset;
15 int arg_idx;
16 const char *cmd;
17 };
18
19 static const struct cec_error_inj_cmd cec_error_inj_cmds[] = {
20 { CEC_ERROR_INJ_RX_NACK_OFFSET, -1, "rx-nack" },
21 { CEC_ERROR_INJ_RX_LOW_DRIVE_OFFSET,
22 CEC_ERROR_INJ_RX_LOW_DRIVE_ARG_IDX, "rx-low-drive" },
23 { CEC_ERROR_INJ_RX_ADD_BYTE_OFFSET, -1, "rx-add-byte" },
24 { CEC_ERROR_INJ_RX_REMOVE_BYTE_OFFSET, -1, "rx-remove-byte" },
25 { CEC_ERROR_INJ_RX_ARB_LOST_OFFSET,
26 CEC_ERROR_INJ_RX_ARB_LOST_ARG_IDX, "rx-arb-lost" },
27
28 { CEC_ERROR_INJ_TX_NO_EOM_OFFSET, -1, "tx-no-eom" },
29 { CEC_ERROR_INJ_TX_EARLY_EOM_OFFSET, -1, "tx-early-eom" },
30 { CEC_ERROR_INJ_TX_ADD_BYTES_OFFSET,
31 CEC_ERROR_INJ_TX_ADD_BYTES_ARG_IDX, "tx-add-bytes" },
32 { CEC_ERROR_INJ_TX_REMOVE_BYTE_OFFSET, -1, "tx-remove-byte" },
33 { CEC_ERROR_INJ_TX_SHORT_BIT_OFFSET,
34 CEC_ERROR_INJ_TX_SHORT_BIT_ARG_IDX, "tx-short-bit" },
35 { CEC_ERROR_INJ_TX_LONG_BIT_OFFSET,
36 CEC_ERROR_INJ_TX_LONG_BIT_ARG_IDX, "tx-long-bit" },
37 { CEC_ERROR_INJ_TX_CUSTOM_BIT_OFFSET,
38 CEC_ERROR_INJ_TX_CUSTOM_BIT_ARG_IDX, "tx-custom-bit" },
39 { CEC_ERROR_INJ_TX_SHORT_START_OFFSET, -1, "tx-short-start" },
40 { CEC_ERROR_INJ_TX_LONG_START_OFFSET, -1, "tx-long-start" },
41 { CEC_ERROR_INJ_TX_CUSTOM_START_OFFSET, -1, "tx-custom-start" },
42 { CEC_ERROR_INJ_TX_LAST_BIT_OFFSET,
43 CEC_ERROR_INJ_TX_LAST_BIT_ARG_IDX, "tx-last-bit" },
44 { CEC_ERROR_INJ_TX_LOW_DRIVE_OFFSET,
45 CEC_ERROR_INJ_TX_LOW_DRIVE_ARG_IDX, "tx-low-drive" },
46 { 0, -1, NULL }
47 };
48
cec_pin_rx_error_inj(struct cec_pin * pin)49 u16 cec_pin_rx_error_inj(struct cec_pin *pin)
50 {
51 u16 cmd = CEC_ERROR_INJ_OP_ANY;
52
53 /* Only when 18 bits have been received do we have a valid cmd */
54 if (!(pin->error_inj[cmd] & CEC_ERROR_INJ_RX_MASK) &&
55 pin->rx_bit >= 18)
56 cmd = pin->rx_msg.msg[1];
57 return (pin->error_inj[cmd] & CEC_ERROR_INJ_RX_MASK) ? cmd :
58 CEC_ERROR_INJ_OP_ANY;
59 }
60
cec_pin_tx_error_inj(struct cec_pin * pin)61 u16 cec_pin_tx_error_inj(struct cec_pin *pin)
62 {
63 u16 cmd = CEC_ERROR_INJ_OP_ANY;
64
65 if (!(pin->error_inj[cmd] & CEC_ERROR_INJ_TX_MASK) &&
66 pin->tx_msg.len > 1)
67 cmd = pin->tx_msg.msg[1];
68 return (pin->error_inj[cmd] & CEC_ERROR_INJ_TX_MASK) ? cmd :
69 CEC_ERROR_INJ_OP_ANY;
70 }
71
cec_pin_error_inj_parse_line(struct cec_adapter * adap,char * line)72 bool cec_pin_error_inj_parse_line(struct cec_adapter *adap, char *line)
73 {
74 static const char *delims = " \t\r";
75 struct cec_pin *pin = adap->pin;
76 unsigned int i;
77 bool has_pos = false;
78 char *p = line;
79 char *token;
80 char *comma;
81 u64 *error;
82 u8 *args;
83 bool has_op;
84 u8 op;
85 u8 mode;
86 u8 pos;
87
88 p = skip_spaces(p);
89 token = strsep(&p, delims);
90 if (!strcmp(token, "clear")) {
91 memset(pin->error_inj, 0, sizeof(pin->error_inj));
92 pin->rx_toggle = pin->tx_toggle = false;
93 pin->tx_ignore_nack_until_eom = false;
94 pin->tx_custom_pulse = false;
95 pin->tx_custom_low_usecs = CEC_TIM_CUSTOM_DEFAULT;
96 pin->tx_custom_high_usecs = CEC_TIM_CUSTOM_DEFAULT;
97 return true;
98 }
99 if (!strcmp(token, "rx-clear")) {
100 for (i = 0; i <= CEC_ERROR_INJ_OP_ANY; i++)
101 pin->error_inj[i] &= ~CEC_ERROR_INJ_RX_MASK;
102 pin->rx_toggle = false;
103 return true;
104 }
105 if (!strcmp(token, "tx-clear")) {
106 for (i = 0; i <= CEC_ERROR_INJ_OP_ANY; i++)
107 pin->error_inj[i] &= ~CEC_ERROR_INJ_TX_MASK;
108 pin->tx_toggle = false;
109 pin->tx_ignore_nack_until_eom = false;
110 pin->tx_custom_pulse = false;
111 pin->tx_custom_low_usecs = CEC_TIM_CUSTOM_DEFAULT;
112 pin->tx_custom_high_usecs = CEC_TIM_CUSTOM_DEFAULT;
113 return true;
114 }
115 if (!strcmp(token, "tx-ignore-nack-until-eom")) {
116 pin->tx_ignore_nack_until_eom = true;
117 return true;
118 }
119 if (!strcmp(token, "tx-custom-pulse")) {
120 pin->tx_custom_pulse = true;
121 cec_pin_start_timer(pin);
122 return true;
123 }
124 if (!p)
125 return false;
126
127 p = skip_spaces(p);
128 if (!strcmp(token, "tx-custom-low-usecs")) {
129 u32 usecs;
130
131 if (kstrtou32(p, 0, &usecs) || usecs > 10000000)
132 return false;
133 pin->tx_custom_low_usecs = usecs;
134 return true;
135 }
136 if (!strcmp(token, "tx-custom-high-usecs")) {
137 u32 usecs;
138
139 if (kstrtou32(p, 0, &usecs) || usecs > 10000000)
140 return false;
141 pin->tx_custom_high_usecs = usecs;
142 return true;
143 }
144
145 comma = strchr(token, ',');
146 if (comma)
147 *comma++ = '\0';
148 if (!strcmp(token, "any")) {
149 has_op = false;
150 error = pin->error_inj + CEC_ERROR_INJ_OP_ANY;
151 args = pin->error_inj_args[CEC_ERROR_INJ_OP_ANY];
152 } else if (!kstrtou8(token, 0, &op)) {
153 has_op = true;
154 error = pin->error_inj + op;
155 args = pin->error_inj_args[op];
156 } else {
157 return false;
158 }
159
160 mode = CEC_ERROR_INJ_MODE_ONCE;
161 if (comma) {
162 if (!strcmp(comma, "off"))
163 mode = CEC_ERROR_INJ_MODE_OFF;
164 else if (!strcmp(comma, "once"))
165 mode = CEC_ERROR_INJ_MODE_ONCE;
166 else if (!strcmp(comma, "always"))
167 mode = CEC_ERROR_INJ_MODE_ALWAYS;
168 else if (!strcmp(comma, "toggle"))
169 mode = CEC_ERROR_INJ_MODE_TOGGLE;
170 else
171 return false;
172 }
173
174 token = strsep(&p, delims);
175 if (p) {
176 p = skip_spaces(p);
177 has_pos = !kstrtou8(p, 0, &pos);
178 }
179
180 if (!strcmp(token, "clear")) {
181 *error = 0;
182 return true;
183 }
184 if (!strcmp(token, "rx-clear")) {
185 *error &= ~CEC_ERROR_INJ_RX_MASK;
186 return true;
187 }
188 if (!strcmp(token, "tx-clear")) {
189 *error &= ~CEC_ERROR_INJ_TX_MASK;
190 return true;
191 }
192
193 for (i = 0; cec_error_inj_cmds[i].cmd; i++) {
194 const char *cmd = cec_error_inj_cmds[i].cmd;
195 unsigned int mode_offset;
196 u64 mode_mask;
197 int arg_idx;
198 bool is_bit_pos = true;
199
200 if (strcmp(token, cmd))
201 continue;
202
203 mode_offset = cec_error_inj_cmds[i].mode_offset;
204 mode_mask = CEC_ERROR_INJ_MODE_MASK << mode_offset;
205 arg_idx = cec_error_inj_cmds[i].arg_idx;
206
207 if (mode_offset == CEC_ERROR_INJ_RX_ARB_LOST_OFFSET) {
208 if (has_op)
209 return false;
210 if (!has_pos)
211 pos = 0x0f;
212 is_bit_pos = false;
213 } else if (mode_offset == CEC_ERROR_INJ_TX_ADD_BYTES_OFFSET) {
214 if (!has_pos || !pos)
215 return false;
216 is_bit_pos = false;
217 }
218
219 if (arg_idx >= 0 && is_bit_pos) {
220 if (!has_pos || pos >= 160)
221 return false;
222 if (has_op && pos < 10 + 8)
223 return false;
224 /* Invalid bit position may not be the Ack bit */
225 if ((mode_offset == CEC_ERROR_INJ_TX_SHORT_BIT_OFFSET ||
226 mode_offset == CEC_ERROR_INJ_TX_LONG_BIT_OFFSET ||
227 mode_offset == CEC_ERROR_INJ_TX_CUSTOM_BIT_OFFSET) &&
228 (pos % 10) == 9)
229 return false;
230 }
231 *error &= ~mode_mask;
232 *error |= (u64)mode << mode_offset;
233 if (arg_idx >= 0)
234 args[arg_idx] = pos;
235 return true;
236 }
237 return false;
238 }
239
cec_pin_show_cmd(struct seq_file * sf,u32 cmd,u8 mode)240 static void cec_pin_show_cmd(struct seq_file *sf, u32 cmd, u8 mode)
241 {
242 if (cmd == CEC_ERROR_INJ_OP_ANY)
243 seq_puts(sf, "any,");
244 else
245 seq_printf(sf, "0x%02x,", cmd);
246 switch (mode) {
247 case CEC_ERROR_INJ_MODE_ONCE:
248 seq_puts(sf, "once ");
249 break;
250 case CEC_ERROR_INJ_MODE_ALWAYS:
251 seq_puts(sf, "always ");
252 break;
253 case CEC_ERROR_INJ_MODE_TOGGLE:
254 seq_puts(sf, "toggle ");
255 break;
256 default:
257 seq_puts(sf, "off ");
258 break;
259 }
260 }
261
cec_pin_error_inj_show(struct cec_adapter * adap,struct seq_file * sf)262 int cec_pin_error_inj_show(struct cec_adapter *adap, struct seq_file *sf)
263 {
264 struct cec_pin *pin = adap->pin;
265 unsigned int i, j;
266
267 seq_puts(sf, "# Clear error injections:\n");
268 seq_puts(sf, "# clear clear all rx and tx error injections\n");
269 seq_puts(sf, "# rx-clear clear all rx error injections\n");
270 seq_puts(sf, "# tx-clear clear all tx error injections\n");
271 seq_puts(sf, "# <op> clear clear all rx and tx error injections for <op>\n");
272 seq_puts(sf, "# <op> rx-clear clear all rx error injections for <op>\n");
273 seq_puts(sf, "# <op> tx-clear clear all tx error injections for <op>\n");
274 seq_puts(sf, "#\n");
275 seq_puts(sf, "# RX error injection:\n");
276 seq_puts(sf, "# <op>[,<mode>] rx-nack NACK the message instead of sending an ACK\n");
277 seq_puts(sf, "# <op>[,<mode>] rx-low-drive <bit> force a low-drive condition at this bit position\n");
278 seq_puts(sf, "# <op>[,<mode>] rx-add-byte add a spurious byte to the received CEC message\n");
279 seq_puts(sf, "# <op>[,<mode>] rx-remove-byte remove the last byte from the received CEC message\n");
280 seq_puts(sf, "# <op>[,<mode>] rx-arb-lost <poll> generate a POLL message to trigger an arbitration lost\n");
281 seq_puts(sf, "#\n");
282 seq_puts(sf, "# TX error injection settings:\n");
283 seq_puts(sf, "# tx-ignore-nack-until-eom ignore early NACKs until EOM\n");
284 seq_puts(sf, "# tx-custom-low-usecs <usecs> define the 'low' time for the custom pulse\n");
285 seq_puts(sf, "# tx-custom-high-usecs <usecs> define the 'high' time for the custom pulse\n");
286 seq_puts(sf, "# tx-custom-pulse transmit the custom pulse once the bus is idle\n");
287 seq_puts(sf, "#\n");
288 seq_puts(sf, "# TX error injection:\n");
289 seq_puts(sf, "# <op>[,<mode>] tx-no-eom don't set the EOM bit\n");
290 seq_puts(sf, "# <op>[,<mode>] tx-early-eom set the EOM bit one byte too soon\n");
291 seq_puts(sf, "# <op>[,<mode>] tx-add-bytes <num> append <num> (1-255) spurious bytes to the message\n");
292 seq_puts(sf, "# <op>[,<mode>] tx-remove-byte drop the last byte from the message\n");
293 seq_puts(sf, "# <op>[,<mode>] tx-short-bit <bit> make this bit shorter than allowed\n");
294 seq_puts(sf, "# <op>[,<mode>] tx-long-bit <bit> make this bit longer than allowed\n");
295 seq_puts(sf, "# <op>[,<mode>] tx-custom-bit <bit> send the custom pulse instead of this bit\n");
296 seq_puts(sf, "# <op>[,<mode>] tx-short-start send a start pulse that's too short\n");
297 seq_puts(sf, "# <op>[,<mode>] tx-long-start send a start pulse that's too long\n");
298 seq_puts(sf, "# <op>[,<mode>] tx-custom-start send the custom pulse instead of the start pulse\n");
299 seq_puts(sf, "# <op>[,<mode>] tx-last-bit <bit> stop sending after this bit\n");
300 seq_puts(sf, "# <op>[,<mode>] tx-low-drive <bit> force a low-drive condition at this bit position\n");
301 seq_puts(sf, "#\n");
302 seq_puts(sf, "# <op> CEC message opcode (0-255) or 'any'\n");
303 seq_puts(sf, "# <mode> 'once' (default), 'always', 'toggle' or 'off'\n");
304 seq_puts(sf, "# <bit> CEC message bit (0-159)\n");
305 seq_puts(sf, "# 10 bits per 'byte': bits 0-7: data, bit 8: EOM, bit 9: ACK\n");
306 seq_puts(sf, "# <poll> CEC poll message used to test arbitration lost (0x00-0xff, default 0x0f)\n");
307 seq_puts(sf, "# <usecs> microseconds (0-10000000, default 1000)\n");
308
309 seq_puts(sf, "\nclear\n");
310
311 for (i = 0; i < ARRAY_SIZE(pin->error_inj); i++) {
312 u64 e = pin->error_inj[i];
313
314 for (j = 0; cec_error_inj_cmds[j].cmd; j++) {
315 const char *cmd = cec_error_inj_cmds[j].cmd;
316 unsigned int mode;
317 unsigned int mode_offset;
318 int arg_idx;
319
320 mode_offset = cec_error_inj_cmds[j].mode_offset;
321 arg_idx = cec_error_inj_cmds[j].arg_idx;
322 mode = (e >> mode_offset) & CEC_ERROR_INJ_MODE_MASK;
323 if (!mode)
324 continue;
325 cec_pin_show_cmd(sf, i, mode);
326 seq_puts(sf, cmd);
327 if (arg_idx >= 0)
328 seq_printf(sf, " %u",
329 pin->error_inj_args[i][arg_idx]);
330 seq_puts(sf, "\n");
331 }
332 }
333
334 if (pin->tx_ignore_nack_until_eom)
335 seq_puts(sf, "tx-ignore-nack-until-eom\n");
336 if (pin->tx_custom_pulse)
337 seq_puts(sf, "tx-custom-pulse\n");
338 if (pin->tx_custom_low_usecs != CEC_TIM_CUSTOM_DEFAULT)
339 seq_printf(sf, "tx-custom-low-usecs %u\n",
340 pin->tx_custom_low_usecs);
341 if (pin->tx_custom_high_usecs != CEC_TIM_CUSTOM_DEFAULT)
342 seq_printf(sf, "tx-custom-high-usecs %u\n",
343 pin->tx_custom_high_usecs);
344 return 0;
345 }
346