blob: 71105fa4c5f91a8cc2dfe97cc49af21c2152be84 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-only
/*
* vivid-cec.c - A Virtual Video Test Driver, cec emulation
*
* Copyright 2016 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
*/
#include <media/cec.h>
#include "vivid-core.h"
#include "vivid-cec.h"
#define CEC_TIM_START_BIT_TOTAL 4500
#define CEC_TIM_START_BIT_LOW 3700
#define CEC_TIM_START_BIT_HIGH 800
#define CEC_TIM_DATA_BIT_TOTAL 2400
#define CEC_TIM_DATA_BIT_0_LOW 1500
#define CEC_TIM_DATA_BIT_0_HIGH 900
#define CEC_TIM_DATA_BIT_1_LOW 600
#define CEC_TIM_DATA_BIT_1_HIGH 1800
void vivid_cec_bus_free_work(struct vivid_dev *dev)
{
spin_lock(&dev->cec_slock);
while (!list_empty(&dev->cec_work_list)) {
struct vivid_cec_work *cw =
list_first_entry(&dev->cec_work_list,
struct vivid_cec_work, list);
spin_unlock(&dev->cec_slock);
cancel_delayed_work_sync(&cw->work);
spin_lock(&dev->cec_slock);
list_del(&cw->list);
cec_transmit_attempt_done(cw->adap, CEC_TX_STATUS_LOW_DRIVE);
kfree(cw);
}
spin_unlock(&dev->cec_slock);
}
static bool vivid_cec_find_dest_adap(struct vivid_dev *dev,
struct cec_adapter *adap, u8 dest)
{
unsigned int i;
if (dest >= 0xf)
return false;
if (adap != dev->cec_rx_adap && dev->cec_rx_adap &&
dev->cec_rx_adap->is_configured &&
cec_has_log_addr(dev->cec_rx_adap, dest))
return true;
for (i = 0; i < MAX_OUTPUTS && dev->cec_tx_adap[i]; i++) {
if (adap == dev->cec_tx_adap[i])
continue;
if (!dev->cec_tx_adap[i]->is_configured)
continue;
if (cec_has_log_addr(dev->cec_tx_adap[i], dest))
return true;
}
return false;
}
static void vivid_cec_pin_adap_events(struct cec_adapter *adap, ktime_t ts,
const struct cec_msg *msg, bool nacked)
{
unsigned int len = nacked ? 1 : msg->len;
unsigned int i;
bool bit;
if (adap == NULL)
return;
/*
* Suffix ULL on constant 10 makes the expression
* CEC_TIM_START_BIT_TOTAL + 10ULL * len * CEC_TIM_DATA_BIT_TOTAL
* to be evaluated using 64-bit unsigned arithmetic (u64), which
* is what ktime_sub_us expects as second argument.
*/
ts = ktime_sub_us(ts, CEC_TIM_START_BIT_TOTAL +
10ULL * len * CEC_TIM_DATA_BIT_TOTAL);
cec_queue_pin_cec_event(adap, false, false, ts);
ts = ktime_add_us(ts, CEC_TIM_START_BIT_LOW);
cec_queue_pin_cec_event(adap, true, false, ts);
ts = ktime_add_us(ts, CEC_TIM_START_BIT_HIGH);
for (i = 0; i < 10 * len; i++) {
switch (i % 10) {
case 0 ... 7:
bit = msg->msg[i / 10] & (0x80 >> (i % 10));
break;
case 8: /* EOM */
bit = i / 10 == msg->len - 1;
break;
case 9: /* ACK */
bit = cec_msg_is_broadcast(msg) ^ nacked;
break;
}
cec_queue_pin_cec_event(adap, false, false, ts);
if (bit)
ts = ktime_add_us(ts, CEC_TIM_DATA_BIT_1_LOW);
else
ts = ktime_add_us(ts, CEC_TIM_DATA_BIT_0_LOW);
cec_queue_pin_cec_event(adap, true, false, ts);
if (bit)
ts = ktime_add_us(ts, CEC_TIM_DATA_BIT_1_HIGH);
else
ts = ktime_add_us(ts, CEC_TIM_DATA_BIT_0_HIGH);
}
}
static void vivid_cec_pin_events(struct vivid_dev *dev,
const struct cec_msg *msg, bool nacked)
{
ktime_t ts = ktime_get();
unsigned int i;
vivid_cec_pin_adap_events(dev->cec_rx_adap, ts, msg, nacked);
for (i = 0; i < MAX_OUTPUTS; i++)
vivid_cec_pin_adap_events(dev->cec_tx_adap[i], ts, msg, nacked);
}
static void vivid_cec_xfer_done_worker(struct work_struct *work)
{
struct vivid_cec_work *cw =
container_of(work, struct vivid_cec_work, work.work);
struct vivid_dev *dev = cw->dev;
struct cec_adapter *adap = cw->adap;
u8 dest = cec_msg_destination(&cw->msg);
bool valid_dest;
unsigned int i;
valid_dest = cec_msg_is_broadcast(&cw->msg);
if (!valid_dest)
valid_dest = vivid_cec_find_dest_adap(dev, adap, dest);
cw->tx_status = valid_dest ? CEC_TX_STATUS_OK : CEC_TX_STATUS_NACK;
spin_lock(&dev->cec_slock);
dev->cec_xfer_time_jiffies = 0;
dev->cec_xfer_start_jiffies = 0;
list_del(&cw->list);
spin_unlock(&dev->cec_slock);
vivid_cec_pin_events(dev, &cw->msg, !valid_dest);
cec_transmit_attempt_done(cw->adap, cw->tx_status);
/* Broadcast message */
if (adap != dev->cec_rx_adap)
cec_received_msg(dev->cec_rx_adap, &cw->msg);
for (i = 0; i < MAX_OUTPUTS && dev->cec_tx_adap[i]; i++)
if (adap != dev->cec_tx_adap[i])
cec_received_msg(dev->cec_tx_adap[i], &cw->msg);
kfree(cw);
}
static void vivid_cec_xfer_try_worker(struct work_struct *work)
{
struct vivid_cec_work *cw =
container_of(work, struct vivid_cec_work, work.work);
struct vivid_dev *dev = cw->dev;
spin_lock(&dev->cec_slock);
if (dev->cec_xfer_time_jiffies) {
list_del(&cw->list);
spin_unlock(&dev->cec_slock);
cec_transmit_attempt_done(cw->adap, CEC_TX_STATUS_ARB_LOST);
kfree(cw);
} else {
INIT_DELAYED_WORK(&cw->work, vivid_cec_xfer_done_worker);
dev->cec_xfer_start_jiffies = jiffies;
dev->cec_xfer_time_jiffies = usecs_to_jiffies(cw->usecs);
spin_unlock(&dev->cec_slock);
schedule_delayed_work(&cw->work, dev->cec_xfer_time_jiffies);
}
}
static int vivid_cec_adap_enable(struct cec_adapter *adap, bool enable)
{
adap->cec_pin_is_high = true;
return 0;
}
static int vivid_cec_adap_log_addr(struct cec_adapter *adap, u8 log_addr)
{
return 0;
}
/*
* One data bit takes 2400 us, each byte needs 10 bits so that's 24000 us
* per byte.
*/
#define USECS_PER_BYTE 24000
static int vivid_cec_adap_transmit(struct cec_adapter *adap, u8 attempts,
u32 signal_free_time, struct cec_msg *msg)
{
struct vivid_dev *dev = cec_get_drvdata(adap);
struct vivid_cec_work *cw = kzalloc(sizeof(*cw), GFP_KERNEL);
long delta_jiffies = 0;
if (cw == NULL)
return -ENOMEM;
cw->dev = dev;
cw->adap = adap;
cw->usecs = CEC_FREE_TIME_TO_USEC(signal_free_time) +
msg->len * USECS_PER_BYTE;
cw->msg = *msg;
spin_lock(&dev->cec_slock);
list_add(&cw->list, &dev->cec_work_list);
if (dev->cec_xfer_time_jiffies == 0) {
INIT_DELAYED_WORK(&cw->work, vivid_cec_xfer_done_worker);
dev->cec_xfer_start_jiffies = jiffies;
dev->cec_xfer_time_jiffies = usecs_to_jiffies(cw->usecs);
delta_jiffies = dev->cec_xfer_time_jiffies;
} else {
INIT_DELAYED_WORK(&cw->work, vivid_cec_xfer_try_worker);
delta_jiffies = dev->cec_xfer_start_jiffies +
dev->cec_xfer_time_jiffies - jiffies;
}
spin_unlock(&dev->cec_slock);
schedule_delayed_work(&cw->work, delta_jiffies < 0 ? 0 : delta_jiffies);
return 0;
}
static int vivid_received(struct cec_adapter *adap, struct cec_msg *msg)
{
struct vivid_dev *dev = cec_get_drvdata(adap);
struct cec_msg reply;
u8 dest = cec_msg_destination(msg);
u8 disp_ctl;
char osd[14];
if (cec_msg_is_broadcast(msg))
dest = adap->log_addrs.log_addr[0];
cec_msg_init(&reply, dest, cec_msg_initiator(msg));
switch (cec_msg_opcode(msg)) {
case CEC_MSG_SET_OSD_STRING:
if (!cec_is_sink(adap))
return -ENOMSG;
cec_ops_set_osd_string(msg, &disp_ctl, osd);
switch (disp_ctl) {
case CEC_OP_DISP_CTL_DEFAULT:
strcpy(dev->osd, osd);
dev->osd_jiffies = jiffies;
break;
case CEC_OP_DISP_CTL_UNTIL_CLEARED:
strcpy(dev->osd, osd);
dev->osd_jiffies = 0;
break;
case CEC_OP_DISP_CTL_CLEAR:
dev->osd[0] = 0;
dev->osd_jiffies = 0;
break;
default:
cec_msg_feature_abort(&reply, cec_msg_opcode(msg),
CEC_OP_ABORT_INVALID_OP);
cec_transmit_msg(adap, &reply, false);
break;
}
break;
default:
return -ENOMSG;
}
return 0;
}
static const struct cec_adap_ops vivid_cec_adap_ops = {
.adap_enable = vivid_cec_adap_enable,
.adap_log_addr = vivid_cec_adap_log_addr,
.adap_transmit = vivid_cec_adap_transmit,
.received = vivid_received,
};
struct cec_adapter *vivid_cec_alloc_adap(struct vivid_dev *dev,
unsigned int idx,
bool is_source)
{
char name[sizeof(dev->vid_out_dev.name) + 2];
u32 caps = CEC_CAP_DEFAULTS | CEC_CAP_MONITOR_ALL | CEC_CAP_MONITOR_PIN;
snprintf(name, sizeof(name), "%s%d",
is_source ? dev->vid_out_dev.name : dev->vid_cap_dev.name,
idx);
return cec_allocate_adapter(&vivid_cec_adap_ops, dev,
name, caps, 1);
}