/*
 * Copyright 2019 Advanced Micro Devices, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Authors: AMD
 *
 */

#include "hdcp.h"

static void push_error_status(struct mod_hdcp *hdcp,
                enum mod_hdcp_status status)
{
        struct mod_hdcp_trace *trace = &hdcp->connection.trace;
        const uint8_t retry_limit = hdcp->connection.link.adjust.retry_limit;

        if (trace->error_count < MAX_NUM_OF_ERROR_TRACE) {
                trace->errors[trace->error_count].status = status;
                trace->errors[trace->error_count].state_id = hdcp->state.id;
                trace->error_count++;
                HDCP_ERROR_TRACE(hdcp, status);
        }

        if (is_hdcp1(hdcp)) {
                hdcp->connection.hdcp1_retry_count++;
                if (hdcp->connection.hdcp1_retry_count == retry_limit)
                        hdcp->connection.link.adjust.hdcp1.disable = 1;
        } else if (is_hdcp2(hdcp)) {
                hdcp->connection.hdcp2_retry_count++;
                if (hdcp->connection.hdcp2_retry_count == retry_limit)
                        hdcp->connection.link.adjust.hdcp2.disable = 1;
        }
}

static uint8_t is_cp_desired_hdcp1(struct mod_hdcp *hdcp)
{
        int i, is_auth_needed = 0;

        /* if all displays on the link don't need authentication,
         * hdcp is not desired
         */
        for (i = 0; i < MAX_NUM_OF_DISPLAYS; i++) {
                if (hdcp->displays[i].state != MOD_HDCP_DISPLAY_INACTIVE &&
                                hdcp->displays[i].adjust.disable != MOD_HDCP_DISPLAY_DISABLE_AUTHENTICATION) {
                        is_auth_needed = 1;
                        break;
                }
        }

        return is_auth_needed &&
                        !hdcp->connection.link.adjust.hdcp1.disable &&
                        !hdcp->connection.is_hdcp1_revoked;
}

static uint8_t is_cp_desired_hdcp2(struct mod_hdcp *hdcp)
{
        int i, is_auth_needed = 0;

        /* if all displays on the link don't need authentication,
         * hdcp is not desired
         */
        for (i = 0; i < MAX_NUM_OF_DISPLAYS; i++) {
                if (hdcp->displays[i].state != MOD_HDCP_DISPLAY_INACTIVE &&
                                hdcp->displays[i].adjust.disable != MOD_HDCP_DISPLAY_DISABLE_AUTHENTICATION) {
                        is_auth_needed = 1;
                        break;
                }
        }

        return is_auth_needed &&
                        !hdcp->connection.link.adjust.hdcp2.disable &&
                        !hdcp->connection.is_hdcp2_revoked;
}

static enum mod_hdcp_status execution(struct mod_hdcp *hdcp,
                struct mod_hdcp_event_context *event_ctx,
                union mod_hdcp_transition_input *input)
{
        enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;

        if (is_in_initialized_state(hdcp)) {
                if (event_ctx->event != MOD_HDCP_EVENT_CALLBACK) {
                        event_ctx->unexpected_event = 1;
                        goto out;
                }
                /* initialize transition input */
                memset(input, 0, sizeof(union mod_hdcp_transition_input));
        } else if (is_in_cp_not_desired_state(hdcp)) {
                if (event_ctx->event != MOD_HDCP_EVENT_CALLBACK) {
                        event_ctx->unexpected_event = 1;
                        goto out;
                }
        } else if (is_in_hdcp1_states(hdcp)) {
                status = mod_hdcp_hdcp1_execution(hdcp, event_ctx, &input->hdcp1);
        } else if (is_in_hdcp1_dp_states(hdcp)) {
                status = mod_hdcp_hdcp1_dp_execution(hdcp,
                                event_ctx, &input->hdcp1);
        } else if (is_in_hdcp2_states(hdcp)) {
                status = mod_hdcp_hdcp2_execution(hdcp, event_ctx, &input->hdcp2);
        } else if (is_in_hdcp2_dp_states(hdcp)) {
                status = mod_hdcp_hdcp2_dp_execution(hdcp,
                                event_ctx, &input->hdcp2);
        } else {
                event_ctx->unexpected_event = 1;
                goto out;
        }
out:
        return status;
}

static enum mod_hdcp_status transition(struct mod_hdcp *hdcp,
                struct mod_hdcp_event_context *event_ctx,
                union mod_hdcp_transition_input *input,
                struct mod_hdcp_output *output)
{
        enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;

        if (event_ctx->unexpected_event)
                goto out;

        if (is_in_initialized_state(hdcp)) {
                if (is_dp_hdcp(hdcp))
                        if (is_cp_desired_hdcp2(hdcp)) {
                                callback_in_ms(0, output);
                                set_state_id(hdcp, output, D2_A0_DETERMINE_RX_HDCP_CAPABLE);
                        } else if (is_cp_desired_hdcp1(hdcp)) {
                                callback_in_ms(0, output);
                                set_state_id(hdcp, output, D1_A0_DETERMINE_RX_HDCP_CAPABLE);
                        } else {
                                callback_in_ms(0, output);
                                set_state_id(hdcp, output, HDCP_CP_NOT_DESIRED);
                                set_auth_complete(hdcp, output);
                        }
                else if (is_hdmi_dvi_sl_hdcp(hdcp))
                        if (is_cp_desired_hdcp2(hdcp)) {
                                callback_in_ms(0, output);
                                set_state_id(hdcp, output, H2_A0_KNOWN_HDCP2_CAPABLE_RX);
                        } else if (is_cp_desired_hdcp1(hdcp)) {
                                callback_in_ms(0, output);
                                set_state_id(hdcp, output, H1_A0_WAIT_FOR_ACTIVE_RX);
                        } else {
                                callback_in_ms(0, output);
                                set_state_id(hdcp, output, HDCP_CP_NOT_DESIRED);
                                set_auth_complete(hdcp, output);
                        }
                else {
                        callback_in_ms(0, output);
                        set_state_id(hdcp, output, HDCP_CP_NOT_DESIRED);
                        set_auth_complete(hdcp, output);
                }
        } else if (is_in_cp_not_desired_state(hdcp)) {
                increment_stay_counter(hdcp);
        } else if (is_in_hdcp1_states(hdcp)) {
                status = mod_hdcp_hdcp1_transition(hdcp,
                                event_ctx, &input->hdcp1, output);
        } else if (is_in_hdcp1_dp_states(hdcp)) {
                status = mod_hdcp_hdcp1_dp_transition(hdcp,
                                event_ctx, &input->hdcp1, output);
        } else if (is_in_hdcp2_states(hdcp)) {
                status = mod_hdcp_hdcp2_transition(hdcp,
                                event_ctx, &input->hdcp2, output);
        } else if (is_in_hdcp2_dp_states(hdcp)) {
                status = mod_hdcp_hdcp2_dp_transition(hdcp,
                                event_ctx, &input->hdcp2, output);
        } else {
                status = MOD_HDCP_STATUS_INVALID_STATE;
        }
out:
        return status;
}

static enum mod_hdcp_status reset_authentication(struct mod_hdcp *hdcp,
                struct mod_hdcp_output *output)
{
        enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;

        if (is_hdcp1(hdcp)) {
                if (hdcp->auth.trans_input.hdcp1.create_session != UNKNOWN) {
                        /* TODO - update psp to unify create session failure
                         * recovery between hdcp1 and 2.
                         */
                        mod_hdcp_hdcp1_destroy_session(hdcp);

                }

                HDCP_TOP_RESET_AUTH_TRACE(hdcp);
                memset(&hdcp->auth, 0, sizeof(struct mod_hdcp_authentication));
                memset(&hdcp->state, 0, sizeof(struct mod_hdcp_state));
                set_state_id(hdcp, output, HDCP_INITIALIZED);
        } else if (is_hdcp2(hdcp)) {
                if (hdcp->auth.trans_input.hdcp2.create_session == PASS) {
                        status = mod_hdcp_hdcp2_destroy_session(hdcp);
                        if (status != MOD_HDCP_STATUS_SUCCESS) {
                                output->callback_needed = 0;
                                output->watchdog_timer_needed = 0;
                                goto out;
                        }
                }

                HDCP_TOP_RESET_AUTH_TRACE(hdcp);
                memset(&hdcp->auth, 0, sizeof(struct mod_hdcp_authentication));
                memset(&hdcp->state, 0, sizeof(struct mod_hdcp_state));
                set_state_id(hdcp, output, HDCP_INITIALIZED);
        } else if (is_in_cp_not_desired_state(hdcp)) {
                HDCP_TOP_RESET_AUTH_TRACE(hdcp);
                memset(&hdcp->auth, 0, sizeof(struct mod_hdcp_authentication));
                memset(&hdcp->state, 0, sizeof(struct mod_hdcp_state));
                set_state_id(hdcp, output, HDCP_INITIALIZED);
        }

out:
        /* stop callback and watchdog requests from previous authentication*/
        output->watchdog_timer_stop = 1;
        output->callback_stop = 1;
        return status;
}

static enum mod_hdcp_status reset_connection(struct mod_hdcp *hdcp,
                struct mod_hdcp_output *output)
{
        enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;

        memset(output, 0, sizeof(struct mod_hdcp_output));

        status = reset_authentication(hdcp, output);
        if (status != MOD_HDCP_STATUS_SUCCESS)
                goto out;

        if (current_state(hdcp) != HDCP_UNINITIALIZED) {
                HDCP_TOP_RESET_CONN_TRACE(hdcp);
                set_state_id(hdcp, output, HDCP_UNINITIALIZED);
        }
        memset(&hdcp->connection, 0, sizeof(hdcp->connection));
out:
        return status;
}

static enum mod_hdcp_status update_display_adjustments(struct mod_hdcp *hdcp,
                struct mod_hdcp_display *display,
                struct mod_hdcp_display_adjustment *adj)
{
        enum mod_hdcp_status status = MOD_HDCP_STATUS_NOT_IMPLEMENTED;

        if (is_in_authenticated_states(hdcp) &&
                        is_dp_mst_hdcp(hdcp) &&
                        display->adjust.disable == true &&
                        adj->disable == false) {
                display->adjust.disable = false;
                if (is_hdcp1(hdcp))
                        status = mod_hdcp_hdcp1_enable_dp_stream_encryption(hdcp);
                else if (is_hdcp2(hdcp))
                        status = mod_hdcp_hdcp2_enable_dp_stream_encryption(hdcp);

                if (status != MOD_HDCP_STATUS_SUCCESS)
                        display->adjust.disable = true;
        }

        if (status == MOD_HDCP_STATUS_SUCCESS &&
                memcmp(adj, &display->adjust,
                sizeof(struct mod_hdcp_display_adjustment)) != 0)
                status = MOD_HDCP_STATUS_NOT_IMPLEMENTED;

        return status;
}
/*
 * Implementation of functions in mod_hdcp.h
 */
size_t mod_hdcp_get_memory_size(void)
{
        return sizeof(struct mod_hdcp);
}

enum mod_hdcp_status mod_hdcp_setup(struct mod_hdcp *hdcp,
                struct mod_hdcp_config *config)
{
        struct mod_hdcp_output output;
        enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;

        memset(&output, 0, sizeof(output));
        hdcp->config = *config;
        HDCP_TOP_INTERFACE_TRACE(hdcp);
        status = reset_connection(hdcp, &output);
        if (status != MOD_HDCP_STATUS_SUCCESS)
                push_error_status(hdcp, status);
        return status;
}

enum mod_hdcp_status mod_hdcp_teardown(struct mod_hdcp *hdcp)
{
        enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
        struct mod_hdcp_output output;

        HDCP_TOP_INTERFACE_TRACE(hdcp);
        memset(&output, 0,  sizeof(output));
        status = reset_connection(hdcp, &output);
        if (status == MOD_HDCP_STATUS_SUCCESS)
                memset(hdcp, 0, sizeof(struct mod_hdcp));
        else
                push_error_status(hdcp, status);
        return status;
}

enum mod_hdcp_status mod_hdcp_add_display(struct mod_hdcp *hdcp,
                struct mod_hdcp_link *link, struct mod_hdcp_display *display,
                struct mod_hdcp_output *output)
{
        enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
        struct mod_hdcp_display *display_container = NULL;

        HDCP_TOP_INTERFACE_TRACE_WITH_INDEX(hdcp, display->index);
        memset(output, 0, sizeof(struct mod_hdcp_output));

        /* skip inactive display */
        if (display->state != MOD_HDCP_DISPLAY_ACTIVE) {
                status = MOD_HDCP_STATUS_SUCCESS;
                goto out;
        }

        /* check existing display container */
        if (get_active_display_at_index(hdcp, display->index)) {
                status = MOD_HDCP_STATUS_SUCCESS;
                goto out;
        }

        /* find an empty display container */
        display_container = get_empty_display_container(hdcp);
        if (!display_container) {
                status = MOD_HDCP_STATUS_DISPLAY_OUT_OF_BOUND;
                goto out;
        }

        /* reset existing authentication status */
        status = reset_authentication(hdcp, output);
        if (status != MOD_HDCP_STATUS_SUCCESS)
                goto out;

        /* reset retry counters */
        reset_retry_counts(hdcp);

        /* reset trace */
        memset(&hdcp->connection.trace, 0, sizeof(hdcp->connection.trace));

        /* add display to connection */
        hdcp->connection.link = *link;
        *display_container = *display;
        status = mod_hdcp_add_display_to_topology(hdcp, display_container);

        if (status != MOD_HDCP_STATUS_SUCCESS)
                goto out;

        /* request authentication */
        if (current_state(hdcp) != HDCP_INITIALIZED)
                set_state_id(hdcp, output, HDCP_INITIALIZED);
        callback_in_ms(hdcp->connection.link.adjust.auth_delay * 1000, output);
out:
        if (status != MOD_HDCP_STATUS_SUCCESS)
                push_error_status(hdcp, status);

        return status;
}

enum mod_hdcp_status mod_hdcp_remove_display(struct mod_hdcp *hdcp,
                uint8_t index, struct mod_hdcp_output *output)
{
        enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
        struct mod_hdcp_display *display = NULL;

        HDCP_TOP_INTERFACE_TRACE_WITH_INDEX(hdcp, index);
        memset(output, 0, sizeof(struct mod_hdcp_output));

        /* find display in connection */
        display = get_active_display_at_index(hdcp, index);
        if (!display) {
                status = MOD_HDCP_STATUS_SUCCESS;
                goto out;
        }

        /* stop current authentication */
        status = reset_authentication(hdcp, output);
        if (status != MOD_HDCP_STATUS_SUCCESS)
                goto out;

        /* clear retry counters */
        reset_retry_counts(hdcp);

        /* reset trace */
        memset(&hdcp->connection.trace, 0, sizeof(hdcp->connection.trace));

        /* remove display */
        status = mod_hdcp_remove_display_from_topology(hdcp, index);
        if (status != MOD_HDCP_STATUS_SUCCESS)
                goto out;
        memset(display, 0, sizeof(struct mod_hdcp_display));

        /* request authentication when connection is not reset */
        if (current_state(hdcp) != HDCP_UNINITIALIZED)
                callback_in_ms(hdcp->connection.link.adjust.auth_delay * 1000,
                                output);
out:
        if (status != MOD_HDCP_STATUS_SUCCESS)
                push_error_status(hdcp, status);
        return status;
}

enum mod_hdcp_status mod_hdcp_update_display(struct mod_hdcp *hdcp,
                uint8_t index,
                struct mod_hdcp_link_adjustment *link_adjust,
                struct mod_hdcp_display_adjustment *display_adjust,
                struct mod_hdcp_output *output)
{
        enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
        struct mod_hdcp_display *display = NULL;

        HDCP_TOP_INTERFACE_TRACE_WITH_INDEX(hdcp, index);
        memset(output, 0, sizeof(struct mod_hdcp_output));

        /* find display in connection */
        display = get_active_display_at_index(hdcp, index);
        if (!display) {
                status = MOD_HDCP_STATUS_DISPLAY_NOT_FOUND;
                goto out;
        }

        /* skip if no changes */
        if (memcmp(link_adjust, &hdcp->connection.link.adjust,
                        sizeof(struct mod_hdcp_link_adjustment)) == 0 &&
                        memcmp(display_adjust, &display->adjust,
                                        sizeof(struct mod_hdcp_display_adjustment)) == 0) {
                status = MOD_HDCP_STATUS_SUCCESS;
                goto out;
        }

        if (memcmp(link_adjust, &hdcp->connection.link.adjust,
                        sizeof(struct mod_hdcp_link_adjustment)) == 0 &&
                        memcmp(display_adjust, &display->adjust,
                                        sizeof(struct mod_hdcp_display_adjustment)) != 0) {
                status = update_display_adjustments(hdcp, display, display_adjust);
                if (status != MOD_HDCP_STATUS_NOT_IMPLEMENTED)
                        goto out;
        }

        /* stop current authentication */
        status = reset_authentication(hdcp, output);
        if (status != MOD_HDCP_STATUS_SUCCESS)
                goto out;

        /* clear retry counters */
        reset_retry_counts(hdcp);

        /* reset trace */
        memset(&hdcp->connection.trace, 0, sizeof(hdcp->connection.trace));

        /* set new adjustment */
        hdcp->connection.link.adjust = *link_adjust;
        display->adjust = *display_adjust;

        /* request authentication when connection is not reset */
        if (current_state(hdcp) != HDCP_UNINITIALIZED)
                /* wait 100ms to debounce simultaneous updates for different indices */
                callback_in_ms(100, output);

out:
        if (status != MOD_HDCP_STATUS_SUCCESS)
                push_error_status(hdcp, status);
        return status;
}

enum mod_hdcp_status mod_hdcp_query_display(struct mod_hdcp *hdcp,
                uint8_t index, struct mod_hdcp_display_query *query)
{
        enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
        struct mod_hdcp_display *display = NULL;

        /* find display in connection */
        display = get_active_display_at_index(hdcp, index);
        if (!display) {
                status = MOD_HDCP_STATUS_DISPLAY_NOT_FOUND;
                goto out;
        }

        /* populate query */
        query->link = &hdcp->connection.link;
        query->display = display;
        query->trace = &hdcp->connection.trace;
        query->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP_OFF;

        if (is_display_encryption_enabled(display)) {
                if (is_hdcp1(hdcp)) {
                        query->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP1_ON;
                } else if (is_hdcp2(hdcp)) {
                        if (query->link->adjust.hdcp2.force_type == MOD_HDCP_FORCE_TYPE_0)
                                query->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP2_TYPE0_ON;
                        else if (query->link->adjust.hdcp2.force_type == MOD_HDCP_FORCE_TYPE_1)
                                query->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP2_TYPE1_ON;
                        else
                                query->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP2_ON;
                }
        } else {
                query->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP_OFF;
        }

out:
        return status;
}

enum mod_hdcp_status mod_hdcp_reset_connection(struct mod_hdcp *hdcp,
                struct mod_hdcp_output *output)
{
        enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;

        HDCP_TOP_INTERFACE_TRACE(hdcp);
        status = reset_connection(hdcp, output);
        if (status != MOD_HDCP_STATUS_SUCCESS)
                push_error_status(hdcp, status);

        return status;
}

enum mod_hdcp_status mod_hdcp_process_event(struct mod_hdcp *hdcp,
                enum mod_hdcp_event event, struct mod_hdcp_output *output)
{
        enum mod_hdcp_status exec_status, trans_status, reset_status, status;
        struct mod_hdcp_event_context event_ctx;

        HDCP_EVENT_TRACE(hdcp, event);
        memset(output, 0, sizeof(struct mod_hdcp_output));
        memset(&event_ctx, 0, sizeof(struct mod_hdcp_event_context));
        event_ctx.event = event;

        /* execute and transition */
        exec_status = execution(hdcp, &event_ctx, &hdcp->auth.trans_input);
        trans_status = transition(
                        hdcp, &event_ctx, &hdcp->auth.trans_input, output);
        if (trans_status == MOD_HDCP_STATUS_SUCCESS) {
                status = MOD_HDCP_STATUS_SUCCESS;
        } else if (exec_status == MOD_HDCP_STATUS_SUCCESS) {
                status = MOD_HDCP_STATUS_INTERNAL_POLICY_FAILURE;
                push_error_status(hdcp, status);
        } else {
                status = exec_status;
                push_error_status(hdcp, status);
        }

        /* reset authentication if needed */
        if (trans_status == MOD_HDCP_STATUS_RESET_NEEDED) {
                mod_hdcp_log_ddc_trace(hdcp);
                reset_status = reset_authentication(hdcp, output);
                if (reset_status != MOD_HDCP_STATUS_SUCCESS)
                        push_error_status(hdcp, reset_status);
        }

        /* Clear CP_IRQ status if needed */
        if (event_ctx.event == MOD_HDCP_EVENT_CPIRQ) {
                status = mod_hdcp_clear_cp_irq_status(hdcp);
                if (status != MOD_HDCP_STATUS_SUCCESS)
                        push_error_status(hdcp, status);
        }

        return status;
}

enum mod_hdcp_operation_mode mod_hdcp_signal_type_to_operation_mode(
                enum signal_type signal)
{
        enum mod_hdcp_operation_mode mode = MOD_HDCP_MODE_OFF;

        switch (signal) {
        case SIGNAL_TYPE_DVI_SINGLE_LINK:
        case SIGNAL_TYPE_HDMI_TYPE_A:
                mode = MOD_HDCP_MODE_DEFAULT;
                break;
        case SIGNAL_TYPE_EDP:
        case SIGNAL_TYPE_DISPLAY_PORT:
        case SIGNAL_TYPE_DISPLAY_PORT_MST:
                mode = MOD_HDCP_MODE_DP;
                break;
        default:
                break;
        }

        return mode;
}