diff options
Diffstat (limited to 'drivers/media/platform/tegra-cec/tegra_cec.c')
| -rw-r--r-- | drivers/media/platform/tegra-cec/tegra_cec.c | 501 |
1 files changed, 501 insertions, 0 deletions
diff --git a/drivers/media/platform/tegra-cec/tegra_cec.c b/drivers/media/platform/tegra-cec/tegra_cec.c new file mode 100644 index 000000000000..b53743f555e8 --- /dev/null +++ b/drivers/media/platform/tegra-cec/tegra_cec.c @@ -0,0 +1,501 @@ +/* + * 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. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#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_REGISTER_OVERRUN | + TEGRA_CEC_INT_STAT_RX_BUS_ANOMALY_DETECTED | + TEGRA_CEC_INT_STAT_RX_START_BIT_DETECTED | + TEGRA_CEC_INT_STAT_RX_BUS_ERROR_DETECTED)) { + cec_write(cec, TEGRA_CEC_INT_STAT, + (TEGRA_CEC_INT_STAT_RX_REGISTER_OVERRUN | + TEGRA_CEC_INT_STAT_RX_BUS_ANOMALY_DETECTED | + TEGRA_CEC_INT_STAT_RX_START_BIT_DETECTED | + TEGRA_CEC_INT_STAT_RX_BUS_ERROR_DETECTED)); + } else 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_REGISTER_OVERRUN); + + 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 platform_device *hdmi_dev; + struct device_node *np; + struct tegra_cec *cec; + struct resource *res; + int ret = 0; + + np = of_parse_phandle(pdev->dev.of_node, "hdmi-phandle", 0); + + if (!np) { + dev_err(&pdev->dev, "Failed to find hdmi node in device tree\n"); + return -ENODEV; + } + hdmi_dev = of_find_device_by_node(np); + if (hdmi_dev == NULL) + return -EPROBE_DEFER; + + 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"); + ret = -EBUSY; + goto cec_error; + } + + 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"); + ret = -EBUSY; + goto cec_error; + } + + cec->tegra_cec_irq = platform_get_irq(pdev, 0); + + if (cec->tegra_cec_irq <= 0) { + ret = -EBUSY; + goto cec_error; + } + + cec->cec_base = devm_ioremap_nocache(&pdev->dev, res->start, + resource_size(res)); + + if (!cec->cec_base) { + dev_err(&pdev->dev, "Unable to grab IOs for device\n"); + ret = -EBUSY; + goto cec_error; + } + + 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"); + ret = -ENOENT; + goto clk_error; + } + + clk_prepare_enable(cec->clk); + + /* 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 cec_error; + } + + cec->notifier = cec_notifier_get(&hdmi_dev->dev); + if (!cec->notifier) { + ret = -ENOMEM; + goto cec_error; + } + + cec->adap = cec_allocate_adapter(&tegra_cec_ops, cec, TEGRA_CEC_NAME, + CEC_CAP_DEFAULTS | CEC_CAP_MONITOR_ALL, + CEC_MAX_LOG_ADDRS); + if (IS_ERR(cec->adap)) { + ret = -ENOMEM; + dev_err(&pdev->dev, "Couldn't create cec adapter\n"); + goto cec_error; + } + ret = cec_register_adapter(cec->adap, &pdev->dev); + if (ret) { + dev_err(&pdev->dev, "Couldn't register device\n"); + goto cec_error; + } + + cec_register_cec_notifier(cec->adap, cec->notifier); + + return 0; + +cec_error: + if (cec->notifier) + cec_notifier_put(cec->notifier); + cec_delete_adapter(cec->adap); + clk_disable_unprepare(cec->clk); +clk_error: + 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_unregister_adapter(cec->adap); + cec_notifier_put(cec->notifier); + + 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"); + + clk_prepare_enable(cec->clk); + + return 0; +} +#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); |