media: cec-pin-error-inj: parse/show error injection
Add support to the CEC Pin framework to parse error injection commands
and to show them.
The next patch will do the actual implementation of this.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
diff --git a/drivers/media/cec/cec-pin-error-inj.c b/drivers/media/cec/cec-pin-error-inj.c
new file mode 100644
index 0000000..aaa899a
--- /dev/null
+++ b/drivers/media/cec/cec-pin-error-inj.c
@@ -0,0 +1,342 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2017 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
+ */
+
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/sched/types.h>
+
+#include <media/cec-pin.h>
+#include "cec-pin-priv.h"
+
+struct cec_error_inj_cmd {
+ unsigned int mode_offset;
+ int arg_idx;
+ const char *cmd;
+};
+
+static const struct cec_error_inj_cmd cec_error_inj_cmds[] = {
+ { CEC_ERROR_INJ_RX_NACK_OFFSET, -1, "rx-nack" },
+ { CEC_ERROR_INJ_RX_LOW_DRIVE_OFFSET,
+ CEC_ERROR_INJ_RX_LOW_DRIVE_ARG_IDX, "rx-low-drive" },
+ { CEC_ERROR_INJ_RX_ADD_BYTE_OFFSET, -1, "rx-add-byte" },
+ { CEC_ERROR_INJ_RX_REMOVE_BYTE_OFFSET, -1, "rx-remove-byte" },
+ { CEC_ERROR_INJ_RX_ARB_LOST_OFFSET,
+ CEC_ERROR_INJ_RX_ARB_LOST_ARG_IDX, "rx-arb-lost" },
+
+ { CEC_ERROR_INJ_TX_NO_EOM_OFFSET, -1, "tx-no-eom" },
+ { CEC_ERROR_INJ_TX_EARLY_EOM_OFFSET, -1, "tx-early-eom" },
+ { CEC_ERROR_INJ_TX_ADD_BYTES_OFFSET,
+ CEC_ERROR_INJ_TX_ADD_BYTES_ARG_IDX, "tx-add-bytes" },
+ { CEC_ERROR_INJ_TX_REMOVE_BYTE_OFFSET, -1, "tx-remove-byte" },
+ { CEC_ERROR_INJ_TX_SHORT_BIT_OFFSET,
+ CEC_ERROR_INJ_TX_SHORT_BIT_ARG_IDX, "tx-short-bit" },
+ { CEC_ERROR_INJ_TX_LONG_BIT_OFFSET,
+ CEC_ERROR_INJ_TX_LONG_BIT_ARG_IDX, "tx-long-bit" },
+ { CEC_ERROR_INJ_TX_CUSTOM_BIT_OFFSET,
+ CEC_ERROR_INJ_TX_CUSTOM_BIT_ARG_IDX, "tx-custom-bit" },
+ { CEC_ERROR_INJ_TX_SHORT_START_OFFSET, -1, "tx-short-start" },
+ { CEC_ERROR_INJ_TX_LONG_START_OFFSET, -1, "tx-long-start" },
+ { CEC_ERROR_INJ_TX_CUSTOM_START_OFFSET, -1, "tx-custom-start" },
+ { CEC_ERROR_INJ_TX_LAST_BIT_OFFSET,
+ CEC_ERROR_INJ_TX_LAST_BIT_ARG_IDX, "tx-last-bit" },
+ { CEC_ERROR_INJ_TX_LOW_DRIVE_OFFSET,
+ CEC_ERROR_INJ_TX_LOW_DRIVE_ARG_IDX, "tx-low-drive" },
+ { 0, -1, NULL }
+};
+
+u16 cec_pin_rx_error_inj(struct cec_pin *pin)
+{
+ u16 cmd = CEC_ERROR_INJ_OP_ANY;
+
+ /* Only when 18 bits have been received do we have a valid cmd */
+ if (!(pin->error_inj[cmd] & CEC_ERROR_INJ_RX_MASK) &&
+ pin->rx_bit >= 18)
+ cmd = pin->rx_msg.msg[1];
+ return (pin->error_inj[cmd] & CEC_ERROR_INJ_RX_MASK) ? cmd :
+ CEC_ERROR_INJ_OP_ANY;
+}
+
+u16 cec_pin_tx_error_inj(struct cec_pin *pin)
+{
+ u16 cmd = CEC_ERROR_INJ_OP_ANY;
+
+ if (!(pin->error_inj[cmd] & CEC_ERROR_INJ_TX_MASK) &&
+ pin->tx_msg.len > 1)
+ cmd = pin->tx_msg.msg[1];
+ return (pin->error_inj[cmd] & CEC_ERROR_INJ_TX_MASK) ? cmd :
+ CEC_ERROR_INJ_OP_ANY;
+}
+
+bool cec_pin_error_inj_parse_line(struct cec_adapter *adap, char *line)
+{
+ static const char *delims = " \t\r";
+ struct cec_pin *pin = adap->pin;
+ unsigned int i;
+ bool has_pos = false;
+ char *p = line;
+ char *token;
+ char *comma;
+ u64 *error;
+ u8 *args;
+ bool has_op;
+ u32 op;
+ u8 mode;
+ u8 pos;
+ u8 v;
+
+ p = skip_spaces(p);
+ token = strsep(&p, delims);
+ if (!strcmp(token, "clear")) {
+ memset(pin->error_inj, 0, sizeof(pin->error_inj));
+ pin->rx_toggle = pin->tx_toggle = false;
+ pin->tx_ignore_nack_until_eom = false;
+ pin->tx_custom_pulse = false;
+ pin->tx_custom_low_usecs = CEC_TIM_CUSTOM_DEFAULT;
+ pin->tx_custom_high_usecs = CEC_TIM_CUSTOM_DEFAULT;
+ return true;
+ }
+ if (!strcmp(token, "rx-clear")) {
+ for (i = 0; i <= CEC_ERROR_INJ_OP_ANY; i++)
+ pin->error_inj[i] &= ~CEC_ERROR_INJ_RX_MASK;
+ pin->rx_toggle = false;
+ return true;
+ }
+ if (!strcmp(token, "tx-clear")) {
+ for (i = 0; i <= CEC_ERROR_INJ_OP_ANY; i++)
+ pin->error_inj[i] &= ~CEC_ERROR_INJ_TX_MASK;
+ pin->tx_toggle = false;
+ pin->tx_ignore_nack_until_eom = false;
+ pin->tx_custom_pulse = false;
+ pin->tx_custom_low_usecs = CEC_TIM_CUSTOM_DEFAULT;
+ pin->tx_custom_high_usecs = CEC_TIM_CUSTOM_DEFAULT;
+ return true;
+ }
+ if (!strcmp(token, "tx-ignore-nack-until-eom")) {
+ pin->tx_ignore_nack_until_eom = true;
+ return true;
+ }
+ if (!strcmp(token, "tx-custom-pulse")) {
+ pin->tx_custom_pulse = true;
+ cec_pin_start_timer(pin);
+ return true;
+ }
+ if (!p)
+ return false;
+
+ p = skip_spaces(p);
+ if (!strcmp(token, "tx-custom-low-usecs")) {
+ u32 usecs;
+
+ if (kstrtou32(p, 0, &usecs) || usecs > 10000000)
+ return false;
+ pin->tx_custom_low_usecs = usecs;
+ return true;
+ }
+ if (!strcmp(token, "tx-custom-high-usecs")) {
+ u32 usecs;
+
+ if (kstrtou32(p, 0, &usecs) || usecs > 10000000)
+ return false;
+ pin->tx_custom_high_usecs = usecs;
+ return true;
+ }
+
+ comma = strchr(token, ',');
+ if (comma)
+ *comma++ = '\0';
+ if (!strcmp(token, "any"))
+ op = CEC_ERROR_INJ_OP_ANY;
+ else if (!kstrtou8(token, 0, &v))
+ op = v;
+ else
+ return false;
+ mode = CEC_ERROR_INJ_MODE_ONCE;
+ if (comma) {
+ if (!strcmp(comma, "off"))
+ mode = CEC_ERROR_INJ_MODE_OFF;
+ else if (!strcmp(comma, "once"))
+ mode = CEC_ERROR_INJ_MODE_ONCE;
+ else if (!strcmp(comma, "always"))
+ mode = CEC_ERROR_INJ_MODE_ALWAYS;
+ else if (!strcmp(comma, "toggle"))
+ mode = CEC_ERROR_INJ_MODE_TOGGLE;
+ else
+ return false;
+ }
+
+ error = pin->error_inj + op;
+ args = pin->error_inj_args[op];
+ has_op = op <= 0xff;
+
+ token = strsep(&p, delims);
+ if (p) {
+ p = skip_spaces(p);
+ has_pos = !kstrtou8(p, 0, &pos);
+ }
+
+ if (!strcmp(token, "clear")) {
+ *error = 0;
+ return true;
+ }
+ if (!strcmp(token, "rx-clear")) {
+ *error &= ~CEC_ERROR_INJ_RX_MASK;
+ return true;
+ }
+ if (!strcmp(token, "tx-clear")) {
+ *error &= ~CEC_ERROR_INJ_TX_MASK;
+ return true;
+ }
+
+ for (i = 0; cec_error_inj_cmds[i].cmd; i++) {
+ const char *cmd = cec_error_inj_cmds[i].cmd;
+ unsigned int mode_offset;
+ u64 mode_mask;
+ int arg_idx;
+ bool is_bit_pos = true;
+
+ if (strcmp(token, cmd))
+ continue;
+
+ mode_offset = cec_error_inj_cmds[i].mode_offset;
+ mode_mask = CEC_ERROR_INJ_MODE_MASK << mode_offset;
+ arg_idx = cec_error_inj_cmds[i].arg_idx;
+
+ if (mode_offset == CEC_ERROR_INJ_RX_ARB_LOST_OFFSET ||
+ mode_offset == CEC_ERROR_INJ_TX_ADD_BYTES_OFFSET)
+ is_bit_pos = false;
+
+ if (mode_offset == CEC_ERROR_INJ_RX_ARB_LOST_OFFSET) {
+ if (has_op)
+ return false;
+ if (!has_pos)
+ pos = 0x0f;
+ }
+ if (arg_idx >= 0 && is_bit_pos) {
+ if (!has_pos || pos >= 160)
+ return false;
+ if (has_op && pos < 10 + 8)
+ return false;
+ /* Invalid bit position may not be the Ack bit */
+ if ((mode_offset == CEC_ERROR_INJ_TX_SHORT_BIT_OFFSET ||
+ mode_offset == CEC_ERROR_INJ_TX_LONG_BIT_OFFSET ||
+ mode_offset == CEC_ERROR_INJ_TX_CUSTOM_BIT_OFFSET) &&
+ (pos % 10) == 9)
+ return false;
+ }
+ *error &= ~mode_mask;
+ *error |= (u64)mode << mode_offset;
+ if (arg_idx >= 0)
+ args[arg_idx] = pos;
+ return true;
+ }
+ return false;
+}
+
+static void cec_pin_show_cmd(struct seq_file *sf, u32 cmd, u8 mode)
+{
+ if (cmd == CEC_ERROR_INJ_OP_ANY)
+ seq_puts(sf, "any,");
+ else
+ seq_printf(sf, "0x%02x,", cmd);
+ switch (mode) {
+ case CEC_ERROR_INJ_MODE_ONCE:
+ seq_puts(sf, "once ");
+ break;
+ case CEC_ERROR_INJ_MODE_ALWAYS:
+ seq_puts(sf, "always ");
+ break;
+ case CEC_ERROR_INJ_MODE_TOGGLE:
+ seq_puts(sf, "toggle ");
+ break;
+ default:
+ seq_puts(sf, "off ");
+ break;
+ }
+}
+
+int cec_pin_error_inj_show(struct cec_adapter *adap, struct seq_file *sf)
+{
+ struct cec_pin *pin = adap->pin;
+ unsigned int i, j;
+
+ seq_puts(sf, "# Clear error injections:\n");
+ seq_puts(sf, "# clear clear all rx and tx error injections\n");
+ seq_puts(sf, "# rx-clear clear all rx error injections\n");
+ seq_puts(sf, "# tx-clear clear all tx error injections\n");
+ seq_puts(sf, "# <op> clear clear all rx and tx error injections for <op>\n");
+ seq_puts(sf, "# <op> rx-clear clear all rx error injections for <op>\n");
+ seq_puts(sf, "# <op> tx-clear clear all tx error injections for <op>\n");
+ seq_puts(sf, "#\n");
+ seq_puts(sf, "# RX error injection:\n");
+ seq_puts(sf, "# <op>[,<mode>] rx-nack NACK the message instead of sending an ACK\n");
+ seq_puts(sf, "# <op>[,<mode>] rx-low-drive <bit> force a low-drive condition at this bit position\n");
+ seq_puts(sf, "# <op>[,<mode>] rx-add-byte add a spurious byte to the received CEC message\n");
+ seq_puts(sf, "# <op>[,<mode>] rx-remove-byte remove the last byte from the received CEC message\n");
+ seq_puts(sf, "# <op>[,<mode>] rx-arb-lost <poll> generate a POLL message to trigger an arbitration lost\n");
+ seq_puts(sf, "#\n");
+ seq_puts(sf, "# TX error injection settings:\n");
+ seq_puts(sf, "# tx-ignore-nack-until-eom ignore early NACKs until EOM\n");
+ seq_puts(sf, "# tx-custom-low-usecs <usecs> define the 'low' time for the custom pulse\n");
+ seq_puts(sf, "# tx-custom-high-usecs <usecs> define the 'high' time for the custom pulse\n");
+ seq_puts(sf, "# tx-custom-pulse transmit the custom pulse once the bus is idle\n");
+ seq_puts(sf, "#\n");
+ seq_puts(sf, "# TX error injection:\n");
+ seq_puts(sf, "# <op>[,<mode>] tx-no-eom don't set the EOM bit\n");
+ seq_puts(sf, "# <op>[,<mode>] tx-early-eom set the EOM bit one byte too soon\n");
+ seq_puts(sf, "# <op>[,<mode>] tx-add-bytes <num> append <num> (1-255) spurious bytes to the message\n");
+ seq_puts(sf, "# <op>[,<mode>] tx-remove-byte drop the last byte from the message\n");
+ seq_puts(sf, "# <op>[,<mode>] tx-short-bit <bit> make this bit shorter than allowed\n");
+ seq_puts(sf, "# <op>[,<mode>] tx-long-bit <bit> make this bit longer than allowed\n");
+ seq_puts(sf, "# <op>[,<mode>] tx-custom-bit <bit> send the custom pulse instead of this bit\n");
+ seq_puts(sf, "# <op>[,<mode>] tx-short-start send a start pulse that's too short\n");
+ seq_puts(sf, "# <op>[,<mode>] tx-long-start send a start pulse that's too long\n");
+ seq_puts(sf, "# <op>[,<mode>] tx-custom-start send the custom pulse instead of the start pulse\n");
+ seq_puts(sf, "# <op>[,<mode>] tx-last-bit <bit> stop sending after this bit\n");
+ seq_puts(sf, "# <op>[,<mode>] tx-low-drive <bit> force a low-drive condition at this bit position\n");
+ seq_puts(sf, "#\n");
+ seq_puts(sf, "# <op> CEC message opcode (0-255) or 'any'\n");
+ seq_puts(sf, "# <mode> 'once' (default), 'always', 'toggle' or 'off'\n");
+ seq_puts(sf, "# <bit> CEC message bit (0-159)\n");
+ seq_puts(sf, "# 10 bits per 'byte': bits 0-7: data, bit 8: EOM, bit 9: ACK\n");
+ seq_puts(sf, "# <poll> CEC poll message used to test arbitration lost (0x00-0xff, default 0x0f)\n");
+ seq_puts(sf, "# <usecs> microseconds (0-10000000, default 1000)\n");
+
+ seq_puts(sf, "\nclear\n");
+
+ for (i = 0; i < ARRAY_SIZE(pin->error_inj); i++) {
+ u64 e = pin->error_inj[i];
+
+ for (j = 0; cec_error_inj_cmds[j].cmd; j++) {
+ const char *cmd = cec_error_inj_cmds[j].cmd;
+ unsigned int mode;
+ unsigned int mode_offset;
+ int arg_idx;
+
+ mode_offset = cec_error_inj_cmds[j].mode_offset;
+ arg_idx = cec_error_inj_cmds[j].arg_idx;
+ mode = (e >> mode_offset) & CEC_ERROR_INJ_MODE_MASK;
+ if (!mode)
+ continue;
+ cec_pin_show_cmd(sf, i, mode);
+ seq_puts(sf, cmd);
+ if (arg_idx >= 0)
+ seq_printf(sf, " %u",
+ pin->error_inj_args[i][arg_idx]);
+ seq_puts(sf, "\n");
+ }
+ }
+
+ if (pin->tx_ignore_nack_until_eom)
+ seq_puts(sf, "tx-ignore-nack-until-eom\n");
+ if (pin->tx_custom_pulse)
+ seq_puts(sf, "tx-custom-pulse\n");
+ if (pin->tx_custom_low_usecs != CEC_TIM_CUSTOM_DEFAULT)
+ seq_printf(sf, "tx-custom-low-usecs %u\n",
+ pin->tx_custom_low_usecs);
+ if (pin->tx_custom_high_usecs != CEC_TIM_CUSTOM_DEFAULT)
+ seq_printf(sf, "tx-custom-high-usecs %u\n",
+ pin->tx_custom_high_usecs);
+ return 0;
+}
