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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/media/cec/platform/tegra/tegra_cec.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/media/cec/platform/tegra/tegra_cec.c')
-rw-r--r--drivers/media/cec/platform/tegra/tegra_cec.c483
1 files changed, 483 insertions, 0 deletions
diff --git a/drivers/media/cec/platform/tegra/tegra_cec.c b/drivers/media/cec/platform/tegra/tegra_cec.c
new file mode 100644
index 000000000..5e907395c
--- /dev/null
+++ b/drivers/media/cec/platform/tegra/tegra_cec.c
@@ -0,0 +1,483 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Tegra CEC implementation
+ *
+ * The original 3.10 CEC driver using a custom API:
+ *
+ * Copyright (c) 2012-2015, NVIDIA CORPORATION. All rights reserved.
+ *
+ * Conversion to the CEC framework and to the mainline kernel:
+ *
+ * Copyright 2016-2017 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/pm.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/clk/tegra.h>
+
+#include <media/cec-notifier.h>
+
+#include "tegra_cec.h"
+
+#define TEGRA_CEC_NAME "tegra-cec"
+
+struct tegra_cec {
+ struct cec_adapter *adap;
+ struct device *dev;
+ struct clk *clk;
+ void __iomem *cec_base;
+ struct cec_notifier *notifier;
+ int tegra_cec_irq;
+ bool rx_done;
+ bool tx_done;
+ int tx_status;
+ u8 rx_buf[CEC_MAX_MSG_SIZE];
+ u8 rx_buf_cnt;
+ u32 tx_buf[CEC_MAX_MSG_SIZE];
+ u8 tx_buf_cur;
+ u8 tx_buf_cnt;
+};
+
+static inline u32 cec_read(struct tegra_cec *cec, u32 reg)
+{
+ return readl(cec->cec_base + reg);
+}
+
+static inline void cec_write(struct tegra_cec *cec, u32 reg, u32 val)
+{
+ writel(val, cec->cec_base + reg);
+}
+
+static void tegra_cec_error_recovery(struct tegra_cec *cec)
+{
+ u32 hw_ctrl;
+
+ hw_ctrl = cec_read(cec, TEGRA_CEC_HW_CONTROL);
+ cec_write(cec, TEGRA_CEC_HW_CONTROL, 0);
+ cec_write(cec, TEGRA_CEC_INT_STAT, 0xffffffff);
+ cec_write(cec, TEGRA_CEC_HW_CONTROL, hw_ctrl);
+}
+
+static irqreturn_t tegra_cec_irq_thread_handler(int irq, void *data)
+{
+ struct device *dev = data;
+ struct tegra_cec *cec = dev_get_drvdata(dev);
+
+ if (cec->tx_done) {
+ cec_transmit_attempt_done(cec->adap, cec->tx_status);
+ cec->tx_done = false;
+ }
+ if (cec->rx_done) {
+ struct cec_msg msg = {};
+
+ msg.len = cec->rx_buf_cnt;
+ memcpy(msg.msg, cec->rx_buf, msg.len);
+ cec_received_msg(cec->adap, &msg);
+ cec->rx_done = false;
+ cec->rx_buf_cnt = 0;
+ }
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t tegra_cec_irq_handler(int irq, void *data)
+{
+ struct device *dev = data;
+ struct tegra_cec *cec = dev_get_drvdata(dev);
+ u32 status, mask;
+
+ status = cec_read(cec, TEGRA_CEC_INT_STAT);
+ mask = cec_read(cec, TEGRA_CEC_INT_MASK);
+
+ status &= mask;
+
+ if (!status)
+ return IRQ_HANDLED;
+
+ if (status & TEGRA_CEC_INT_STAT_TX_REGISTER_UNDERRUN) {
+ dev_err(dev, "TX underrun, interrupt timing issue!\n");
+
+ tegra_cec_error_recovery(cec);
+ cec_write(cec, TEGRA_CEC_INT_MASK,
+ mask & ~TEGRA_CEC_INT_MASK_TX_REGISTER_EMPTY);
+
+ cec->tx_done = true;
+ cec->tx_status = CEC_TX_STATUS_ERROR;
+ return IRQ_WAKE_THREAD;
+ }
+
+ if ((status & TEGRA_CEC_INT_STAT_TX_ARBITRATION_FAILED) ||
+ (status & TEGRA_CEC_INT_STAT_TX_BUS_ANOMALY_DETECTED)) {
+ tegra_cec_error_recovery(cec);
+ cec_write(cec, TEGRA_CEC_INT_MASK,
+ mask & ~TEGRA_CEC_INT_MASK_TX_REGISTER_EMPTY);
+
+ cec->tx_done = true;
+ if (status & TEGRA_CEC_INT_STAT_TX_BUS_ANOMALY_DETECTED)
+ cec->tx_status = CEC_TX_STATUS_LOW_DRIVE;
+ else
+ cec->tx_status = CEC_TX_STATUS_ARB_LOST;
+ return IRQ_WAKE_THREAD;
+ }
+
+ if (status & TEGRA_CEC_INT_STAT_TX_FRAME_TRANSMITTED) {
+ cec_write(cec, TEGRA_CEC_INT_STAT,
+ TEGRA_CEC_INT_STAT_TX_FRAME_TRANSMITTED);
+
+ if (status & TEGRA_CEC_INT_STAT_TX_FRAME_OR_BLOCK_NAKD) {
+ tegra_cec_error_recovery(cec);
+
+ cec->tx_done = true;
+ cec->tx_status = CEC_TX_STATUS_NACK;
+ } else {
+ cec->tx_done = true;
+ cec->tx_status = CEC_TX_STATUS_OK;
+ }
+ return IRQ_WAKE_THREAD;
+ }
+
+ if (status & TEGRA_CEC_INT_STAT_TX_FRAME_OR_BLOCK_NAKD)
+ dev_warn(dev, "TX NAKed on the fly!\n");
+
+ if (status & TEGRA_CEC_INT_STAT_TX_REGISTER_EMPTY) {
+ if (cec->tx_buf_cur == cec->tx_buf_cnt) {
+ cec_write(cec, TEGRA_CEC_INT_MASK,
+ mask & ~TEGRA_CEC_INT_MASK_TX_REGISTER_EMPTY);
+ } else {
+ cec_write(cec, TEGRA_CEC_TX_REGISTER,
+ cec->tx_buf[cec->tx_buf_cur++]);
+ cec_write(cec, TEGRA_CEC_INT_STAT,
+ TEGRA_CEC_INT_STAT_TX_REGISTER_EMPTY);
+ }
+ }
+
+ if (status & TEGRA_CEC_INT_STAT_RX_START_BIT_DETECTED) {
+ cec_write(cec, TEGRA_CEC_INT_STAT,
+ TEGRA_CEC_INT_STAT_RX_START_BIT_DETECTED);
+ cec->rx_done = false;
+ cec->rx_buf_cnt = 0;
+ }
+ if (status & TEGRA_CEC_INT_STAT_RX_REGISTER_FULL) {
+ u32 v;
+
+ cec_write(cec, TEGRA_CEC_INT_STAT,
+ TEGRA_CEC_INT_STAT_RX_REGISTER_FULL);
+ v = cec_read(cec, TEGRA_CEC_RX_REGISTER);
+ if (cec->rx_buf_cnt < CEC_MAX_MSG_SIZE)
+ cec->rx_buf[cec->rx_buf_cnt++] = v & 0xff;
+ if (v & TEGRA_CEC_RX_REGISTER_EOM) {
+ cec->rx_done = true;
+ return IRQ_WAKE_THREAD;
+ }
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int tegra_cec_adap_enable(struct cec_adapter *adap, bool enable)
+{
+ struct tegra_cec *cec = adap->priv;
+
+ cec->rx_buf_cnt = 0;
+ cec->tx_buf_cnt = 0;
+ cec->tx_buf_cur = 0;
+
+ cec_write(cec, TEGRA_CEC_HW_CONTROL, 0);
+ cec_write(cec, TEGRA_CEC_INT_MASK, 0);
+ cec_write(cec, TEGRA_CEC_INT_STAT, 0xffffffff);
+ cec_write(cec, TEGRA_CEC_SW_CONTROL, 0);
+
+ if (!enable)
+ return 0;
+
+ cec_write(cec, TEGRA_CEC_INPUT_FILTER, (1U << 31) | 0x20);
+
+ cec_write(cec, TEGRA_CEC_RX_TIMING_0,
+ (0x7a << TEGRA_CEC_RX_TIM0_START_BIT_MAX_LO_TIME_SHIFT) |
+ (0x6d << TEGRA_CEC_RX_TIM0_START_BIT_MIN_LO_TIME_SHIFT) |
+ (0x93 << TEGRA_CEC_RX_TIM0_START_BIT_MAX_DURATION_SHIFT) |
+ (0x86 << TEGRA_CEC_RX_TIM0_START_BIT_MIN_DURATION_SHIFT));
+
+ cec_write(cec, TEGRA_CEC_RX_TIMING_1,
+ (0x35 << TEGRA_CEC_RX_TIM1_DATA_BIT_MAX_LO_TIME_SHIFT) |
+ (0x21 << TEGRA_CEC_RX_TIM1_DATA_BIT_SAMPLE_TIME_SHIFT) |
+ (0x56 << TEGRA_CEC_RX_TIM1_DATA_BIT_MAX_DURATION_SHIFT) |
+ (0x40 << TEGRA_CEC_RX_TIM1_DATA_BIT_MIN_DURATION_SHIFT));
+
+ cec_write(cec, TEGRA_CEC_RX_TIMING_2,
+ (0x50 << TEGRA_CEC_RX_TIM2_END_OF_BLOCK_TIME_SHIFT));
+
+ cec_write(cec, TEGRA_CEC_TX_TIMING_0,
+ (0x74 << TEGRA_CEC_TX_TIM0_START_BIT_LO_TIME_SHIFT) |
+ (0x8d << TEGRA_CEC_TX_TIM0_START_BIT_DURATION_SHIFT) |
+ (0x08 << TEGRA_CEC_TX_TIM0_BUS_XITION_TIME_SHIFT) |
+ (0x71 << TEGRA_CEC_TX_TIM0_BUS_ERROR_LO_TIME_SHIFT));
+
+ cec_write(cec, TEGRA_CEC_TX_TIMING_1,
+ (0x2f << TEGRA_CEC_TX_TIM1_LO_DATA_BIT_LO_TIME_SHIFT) |
+ (0x13 << TEGRA_CEC_TX_TIM1_HI_DATA_BIT_LO_TIME_SHIFT) |
+ (0x4b << TEGRA_CEC_TX_TIM1_DATA_BIT_DURATION_SHIFT) |
+ (0x21 << TEGRA_CEC_TX_TIM1_ACK_NAK_BIT_SAMPLE_TIME_SHIFT));
+
+ cec_write(cec, TEGRA_CEC_TX_TIMING_2,
+ (0x07 << TEGRA_CEC_TX_TIM2_BUS_IDLE_TIME_ADDITIONAL_FRAME_SHIFT) |
+ (0x05 << TEGRA_CEC_TX_TIM2_BUS_IDLE_TIME_NEW_FRAME_SHIFT) |
+ (0x03 << TEGRA_CEC_TX_TIM2_BUS_IDLE_TIME_RETRY_FRAME_SHIFT));
+
+ cec_write(cec, TEGRA_CEC_INT_MASK,
+ TEGRA_CEC_INT_MASK_TX_REGISTER_UNDERRUN |
+ TEGRA_CEC_INT_MASK_TX_FRAME_OR_BLOCK_NAKD |
+ TEGRA_CEC_INT_MASK_TX_ARBITRATION_FAILED |
+ TEGRA_CEC_INT_MASK_TX_BUS_ANOMALY_DETECTED |
+ TEGRA_CEC_INT_MASK_TX_FRAME_TRANSMITTED |
+ TEGRA_CEC_INT_MASK_RX_REGISTER_FULL |
+ TEGRA_CEC_INT_MASK_RX_START_BIT_DETECTED);
+
+ cec_write(cec, TEGRA_CEC_HW_CONTROL, TEGRA_CEC_HWCTRL_TX_RX_MODE);
+ return 0;
+}
+
+static int tegra_cec_adap_log_addr(struct cec_adapter *adap, u8 logical_addr)
+{
+ struct tegra_cec *cec = adap->priv;
+ u32 state = cec_read(cec, TEGRA_CEC_HW_CONTROL);
+
+ if (logical_addr == CEC_LOG_ADDR_INVALID)
+ state &= ~TEGRA_CEC_HWCTRL_RX_LADDR_MASK;
+ else
+ state |= TEGRA_CEC_HWCTRL_RX_LADDR((1 << logical_addr));
+
+ cec_write(cec, TEGRA_CEC_HW_CONTROL, state);
+ return 0;
+}
+
+static int tegra_cec_adap_monitor_all_enable(struct cec_adapter *adap,
+ bool enable)
+{
+ struct tegra_cec *cec = adap->priv;
+ u32 reg = cec_read(cec, TEGRA_CEC_HW_CONTROL);
+
+ if (enable)
+ reg |= TEGRA_CEC_HWCTRL_RX_SNOOP;
+ else
+ reg &= ~TEGRA_CEC_HWCTRL_RX_SNOOP;
+ cec_write(cec, TEGRA_CEC_HW_CONTROL, reg);
+ return 0;
+}
+
+static int tegra_cec_adap_transmit(struct cec_adapter *adap, u8 attempts,
+ u32 signal_free_time_ms, struct cec_msg *msg)
+{
+ bool retry_xfer = signal_free_time_ms == CEC_SIGNAL_FREE_TIME_RETRY;
+ struct tegra_cec *cec = adap->priv;
+ unsigned int i;
+ u32 mode = 0;
+ u32 mask;
+
+ if (cec_msg_is_broadcast(msg))
+ mode = TEGRA_CEC_TX_REG_BCAST;
+
+ cec->tx_buf_cur = 0;
+ cec->tx_buf_cnt = msg->len;
+
+ for (i = 0; i < msg->len; i++) {
+ cec->tx_buf[i] = mode | msg->msg[i];
+ if (i == 0)
+ cec->tx_buf[i] |= TEGRA_CEC_TX_REG_START_BIT;
+ if (i == msg->len - 1)
+ cec->tx_buf[i] |= TEGRA_CEC_TX_REG_EOM;
+ if (i == 0 && retry_xfer)
+ cec->tx_buf[i] |= TEGRA_CEC_TX_REG_RETRY;
+ }
+
+ mask = cec_read(cec, TEGRA_CEC_INT_MASK);
+ cec_write(cec, TEGRA_CEC_INT_MASK,
+ mask | TEGRA_CEC_INT_MASK_TX_REGISTER_EMPTY);
+
+ return 0;
+}
+
+static const struct cec_adap_ops tegra_cec_ops = {
+ .adap_enable = tegra_cec_adap_enable,
+ .adap_log_addr = tegra_cec_adap_log_addr,
+ .adap_transmit = tegra_cec_adap_transmit,
+ .adap_monitor_all_enable = tegra_cec_adap_monitor_all_enable,
+};
+
+static int tegra_cec_probe(struct platform_device *pdev)
+{
+ struct device *hdmi_dev;
+ struct tegra_cec *cec;
+ struct resource *res;
+ int ret = 0;
+
+ hdmi_dev = cec_notifier_parse_hdmi_phandle(&pdev->dev);
+
+ if (IS_ERR(hdmi_dev))
+ return PTR_ERR(hdmi_dev);
+
+ cec = devm_kzalloc(&pdev->dev, sizeof(struct tegra_cec), GFP_KERNEL);
+
+ if (!cec)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+ if (!res) {
+ dev_err(&pdev->dev,
+ "Unable to allocate resources for device\n");
+ return -EBUSY;
+ }
+
+ if (!devm_request_mem_region(&pdev->dev, res->start, resource_size(res),
+ pdev->name)) {
+ dev_err(&pdev->dev,
+ "Unable to request mem region for device\n");
+ return -EBUSY;
+ }
+
+ cec->tegra_cec_irq = platform_get_irq(pdev, 0);
+
+ if (cec->tegra_cec_irq <= 0)
+ return -EBUSY;
+
+ cec->cec_base = devm_ioremap(&pdev->dev, res->start,
+ resource_size(res));
+
+ if (!cec->cec_base) {
+ dev_err(&pdev->dev, "Unable to grab IOs for device\n");
+ return -EBUSY;
+ }
+
+ cec->clk = devm_clk_get(&pdev->dev, "cec");
+
+ if (IS_ERR_OR_NULL(cec->clk)) {
+ dev_err(&pdev->dev, "Can't get clock for CEC\n");
+ return -ENOENT;
+ }
+
+ ret = clk_prepare_enable(cec->clk);
+ if (ret) {
+ dev_err(&pdev->dev, "Unable to prepare clock for CEC\n");
+ return ret;
+ }
+
+ /* set context info. */
+ cec->dev = &pdev->dev;
+
+ platform_set_drvdata(pdev, cec);
+
+ ret = devm_request_threaded_irq(&pdev->dev, cec->tegra_cec_irq,
+ tegra_cec_irq_handler, tegra_cec_irq_thread_handler,
+ 0, "cec_irq", &pdev->dev);
+
+ if (ret) {
+ dev_err(&pdev->dev,
+ "Unable to request interrupt for device\n");
+ goto err_clk;
+ }
+
+ cec->adap = cec_allocate_adapter(&tegra_cec_ops, cec, TEGRA_CEC_NAME,
+ CEC_CAP_DEFAULTS | CEC_CAP_MONITOR_ALL |
+ CEC_CAP_CONNECTOR_INFO,
+ CEC_MAX_LOG_ADDRS);
+ if (IS_ERR(cec->adap)) {
+ ret = -ENOMEM;
+ dev_err(&pdev->dev, "Couldn't create cec adapter\n");
+ goto err_clk;
+ }
+
+ cec->notifier = cec_notifier_cec_adap_register(hdmi_dev, NULL,
+ cec->adap);
+ if (!cec->notifier) {
+ ret = -ENOMEM;
+ goto err_adapter;
+ }
+
+ ret = cec_register_adapter(cec->adap, &pdev->dev);
+ if (ret) {
+ dev_err(&pdev->dev, "Couldn't register device\n");
+ goto err_notifier;
+ }
+
+ return 0;
+
+err_notifier:
+ cec_notifier_cec_adap_unregister(cec->notifier, cec->adap);
+err_adapter:
+ cec_delete_adapter(cec->adap);
+err_clk:
+ clk_disable_unprepare(cec->clk);
+ return ret;
+}
+
+static int tegra_cec_remove(struct platform_device *pdev)
+{
+ struct tegra_cec *cec = platform_get_drvdata(pdev);
+
+ clk_disable_unprepare(cec->clk);
+
+ cec_notifier_cec_adap_unregister(cec->notifier, cec->adap);
+ cec_unregister_adapter(cec->adap);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int tegra_cec_suspend(struct platform_device *pdev, pm_message_t state)
+{
+ struct tegra_cec *cec = platform_get_drvdata(pdev);
+
+ clk_disable_unprepare(cec->clk);
+
+ dev_notice(&pdev->dev, "suspended\n");
+ return 0;
+}
+
+static int tegra_cec_resume(struct platform_device *pdev)
+{
+ struct tegra_cec *cec = platform_get_drvdata(pdev);
+
+ dev_notice(&pdev->dev, "Resuming\n");
+
+ return clk_prepare_enable(cec->clk);
+}
+#endif
+
+static const struct of_device_id tegra_cec_of_match[] = {
+ { .compatible = "nvidia,tegra114-cec", },
+ { .compatible = "nvidia,tegra124-cec", },
+ { .compatible = "nvidia,tegra210-cec", },
+ {},
+};
+
+static struct platform_driver tegra_cec_driver = {
+ .driver = {
+ .name = TEGRA_CEC_NAME,
+ .of_match_table = of_match_ptr(tegra_cec_of_match),
+ },
+ .probe = tegra_cec_probe,
+ .remove = tegra_cec_remove,
+
+#ifdef CONFIG_PM
+ .suspend = tegra_cec_suspend,
+ .resume = tegra_cec_resume,
+#endif
+};
+
+module_platform_driver(tegra_cec_driver);
+
+MODULE_DESCRIPTION("Tegra HDMI CEC driver");
+MODULE_AUTHOR("NVIDIA CORPORATION");
+MODULE_AUTHOR("Cisco Systems, Inc. and/or its affiliates");
+MODULE_LICENSE("GPL v2");