Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 325 insertions, 0 deletions

diff --git a/drivers/media/test-drivers/vivid/vivid-cec.c b/drivers/media/test-drivers/vivid/vivid-cec.c
new file mode 100644
index 0000000000..1f7469ff04
--- /dev/null
+++ b/drivers/media/test-drivers/vivid/vivid-cec.c
@@ -0,0 +1,325 @@
+// 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 <linux/delay.h>
+#include <media/cec.h>
+
+#include "vivid-core.h"
+#include "vivid-cec.h"
+
+#define CEC_START_BIT_US		4500
+#define CEC_DATA_BIT_US			2400
+#define CEC_MARGIN_US			350
+
+struct xfer_on_bus {
+	struct cec_adapter	*adap;
+	u8			status;
+};
+
+static bool 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 bool xfer_ready(struct vivid_dev *dev)
+{
+	unsigned int i;
+	bool ready = false;
+
+	spin_lock(&dev->cec_xfers_slock);
+	for (i = 0; i < ARRAY_SIZE(dev->xfers); i++) {
+		if (dev->xfers[i].sft &&
+		    dev->xfers[i].sft <= dev->cec_sft) {
+			ready = true;
+			break;
+		}
+	}
+	spin_unlock(&dev->cec_xfers_slock);
+
+	return ready;
+}
+
+/*
+ * If an adapter tries to send successive messages, it must wait for the
+ * longest signal-free time between its transmissions. But, if another
+ * adapter sends a message in the interim, then the wait can be reduced
+ * because the messages are no longer successive. Make these adjustments
+ * if necessary. Should be called holding cec_xfers_slock.
+ */
+static void adjust_sfts(struct vivid_dev *dev)
+{
+	unsigned int i;
+	u8 initiator;
+
+	for (i = 0; i < ARRAY_SIZE(dev->xfers); i++) {
+		if (dev->xfers[i].sft <= CEC_SIGNAL_FREE_TIME_RETRY)
+			continue;
+		initiator = dev->xfers[i].msg[0] >> 4;
+		if (initiator == dev->last_initiator)
+			dev->xfers[i].sft = CEC_SIGNAL_FREE_TIME_NEXT_XFER;
+		else
+			dev->xfers[i].sft = CEC_SIGNAL_FREE_TIME_NEW_INITIATOR;
+	}
+}
+
+/*
+ * The main emulation of the bus on which CEC adapters attempt to send
+ * messages to each other. The bus keeps track of how long it has been
+ * signal-free and accepts a pending transmission only if the state of
+ * the bus matches the transmission's signal-free requirements. It calls
+ * cec_transmit_attempt_done() for all transmits that enter the bus and
+ * cec_received_msg() for successful transmits.
+ */
+int vivid_cec_bus_thread(void *_dev)
+{
+	u32 last_sft;
+	unsigned int i;
+	unsigned int dest;
+	ktime_t start, end;
+	s64 delta_us, retry_us;
+	struct vivid_dev *dev = _dev;
+
+	dev->cec_sft = CEC_SIGNAL_FREE_TIME_NEXT_XFER;
+	for (;;) {
+		bool first = true;
+		int wait_xfer_us = 0;
+		bool valid_dest = false;
+		int wait_arb_lost_us = 0;
+		unsigned int first_idx = 0;
+		unsigned int first_status = 0;
+		struct cec_msg first_msg = {};
+		struct xfer_on_bus xfers_on_bus[MAX_OUTPUTS] = {};
+
+		wait_event_interruptible(dev->kthread_waitq_cec, xfer_ready(dev) ||
+					 kthread_should_stop());
+		if (kthread_should_stop())
+			break;
+		last_sft = dev->cec_sft;
+		dev->cec_sft = 0;
+		/*
+		 * Move the messages that are ready onto the bus. The adapter with
+		 * the most leading zeros will win control of the bus and any other
+		 * adapters will lose arbitration.
+		 */
+		spin_lock(&dev->cec_xfers_slock);
+		for (i = 0; i < ARRAY_SIZE(dev->xfers); i++) {
+			if (!dev->xfers[i].sft || dev->xfers[i].sft > last_sft)
+				continue;
+			if (first) {
+				first = false;
+				first_idx = i;
+				xfers_on_bus[first_idx].adap = dev->xfers[i].adap;
+				memcpy(first_msg.msg, dev->xfers[i].msg, dev->xfers[i].len);
+				first_msg.len = dev->xfers[i].len;
+			} else {
+				xfers_on_bus[i].adap = dev->xfers[i].adap;
+				xfers_on_bus[i].status = CEC_TX_STATUS_ARB_LOST;
+				/*
+				 * For simplicity wait for all 4 bits of the initiator's
+				 * address even though HDMI specification uses bit-level
+				 * precision.
+				 */
+				wait_arb_lost_us = 4 * CEC_DATA_BIT_US + CEC_START_BIT_US;
+			}
+			dev->xfers[i].sft = 0;
+		}
+		dev->last_initiator = cec_msg_initiator(&first_msg);
+		adjust_sfts(dev);
+		spin_unlock(&dev->cec_xfers_slock);
+
+		dest = cec_msg_destination(&first_msg);
+		valid_dest = cec_msg_is_broadcast(&first_msg);
+		if (!valid_dest)
+			valid_dest = find_dest_adap(dev, xfers_on_bus[first_idx].adap, dest);
+		if (valid_dest) {
+			first_status = CEC_TX_STATUS_OK;
+			/*
+			 * Message length is in bytes, but each byte is transmitted in
+			 * a block of 10 bits.
+			 */
+			wait_xfer_us = first_msg.len * 10 * CEC_DATA_BIT_US;
+		} else {
+			first_status = CEC_TX_STATUS_NACK;
+			/*
+			 * A message that is not acknowledged stops transmitting after
+			 * the header block of 10 bits.
+			 */
+			wait_xfer_us = 10 * CEC_DATA_BIT_US;
+		}
+		wait_xfer_us += CEC_START_BIT_US;
+		xfers_on_bus[first_idx].status = first_status;
+
+		/* Sleep as if sending messages on a real hardware bus. */
+		start = ktime_get();
+		if (wait_arb_lost_us) {
+			usleep_range(wait_arb_lost_us - CEC_MARGIN_US, wait_arb_lost_us);
+			for (i = 0; i < ARRAY_SIZE(xfers_on_bus); i++) {
+				if (xfers_on_bus[i].status != CEC_TX_STATUS_ARB_LOST)
+					continue;
+				cec_transmit_attempt_done(xfers_on_bus[i].adap,
+							  CEC_TX_STATUS_ARB_LOST);
+			}
+			if (kthread_should_stop())
+				break;
+		}
+		wait_xfer_us -= wait_arb_lost_us;
+		usleep_range(wait_xfer_us - CEC_MARGIN_US, wait_xfer_us);
+		cec_transmit_attempt_done(xfers_on_bus[first_idx].adap, first_status);
+		if (kthread_should_stop())
+			break;
+		if (first_status == CEC_TX_STATUS_OK) {
+			if (xfers_on_bus[first_idx].adap != dev->cec_rx_adap)
+				cec_received_msg(dev->cec_rx_adap, &first_msg);
+			for (i = 0; i < MAX_OUTPUTS && dev->cec_tx_adap[i]; i++)
+				if (xfers_on_bus[first_idx].adap != dev->cec_tx_adap[i])
+					cec_received_msg(dev->cec_tx_adap[i], &first_msg);
+		}
+		end = ktime_get();
+		/*
+		 * If the emulated transfer took more or less time than it should
+		 * have, then compensate by adjusting the wait time needed for the
+		 * bus to be signal-free for 3 bit periods (the retry time).
+		 */
+		delta_us = div_s64(end - start, 1000);
+		delta_us -= wait_xfer_us + wait_arb_lost_us;
+		retry_us = CEC_SIGNAL_FREE_TIME_RETRY * CEC_DATA_BIT_US - delta_us;
+		if (retry_us > CEC_MARGIN_US)
+			usleep_range(retry_us - CEC_MARGIN_US, retry_us);
+		dev->cec_sft = CEC_SIGNAL_FREE_TIME_RETRY;
+		/*
+		 * If there are no messages that need to be retried, check if any
+		 * adapters that did not just transmit a message are ready to
+		 * transmit. If none of these adapters are ready, then increase
+		 * the signal-free time so that the bus is available to all
+		 * adapters and go back to waiting for a transmission.
+		 */
+		while (dev->cec_sft >= CEC_SIGNAL_FREE_TIME_RETRY &&
+		       dev->cec_sft < CEC_SIGNAL_FREE_TIME_NEXT_XFER &&
+		       !xfer_ready(dev) && !kthread_should_stop()) {
+			usleep_range(2 * CEC_DATA_BIT_US - CEC_MARGIN_US,
+				     2 * CEC_DATA_BIT_US);
+			dev->cec_sft += 2;
+		}
+	}
+	return 0;
+}
+
+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;
+}
+
+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);
+	u8 idx = cec_msg_initiator(msg);
+
+	spin_lock(&dev->cec_xfers_slock);
+	dev->xfers[idx].adap = adap;
+	memcpy(dev->xfers[idx].msg, msg->msg, CEC_MAX_MSG_SIZE);
+	dev->xfers[idx].len = msg->len;
+	dev->xfers[idx].sft = CEC_SIGNAL_FREE_TIME_RETRY;
+	if (signal_free_time > CEC_SIGNAL_FREE_TIME_RETRY) {
+		if (idx == dev->last_initiator)
+			dev->xfers[idx].sft = CEC_SIGNAL_FREE_TIME_NEXT_XFER;
+		else
+			dev->xfers[idx].sft = CEC_SIGNAL_FREE_TIME_NEW_INITIATOR;
+	}
+	spin_unlock(&dev->cec_xfers_slock);
+	wake_up_interruptible(&dev->kthread_waitq_cec);
+
+	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:
+			strscpy(dev->osd, osd, sizeof(dev->osd));
+			dev->osd_jiffies = jiffies;
+			break;
+		case CEC_OP_DISP_CTL_UNTIL_CLEARED:
+			strscpy(dev->osd, osd, sizeof(dev->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)
+{
+	u32 caps = CEC_CAP_DEFAULTS | CEC_CAP_MONITOR_ALL | CEC_CAP_MONITOR_PIN;
+	char name[32];
+
+	snprintf(name, sizeof(name), "vivid-%03d-vid-%s%d",
+		 dev->inst, is_source ? "out" : "cap", idx);
+	return cec_allocate_adapter(&vivid_cec_adap_ops, dev,
+				    name, caps, CEC_MAX_LOG_ADDRS);
+}