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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.c')
-rw-r--r-- | drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.c | 321 |
1 files changed, 321 insertions, 0 deletions
diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.c new file mode 100644 index 000000000..c8f44bcb2 --- /dev/null +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.c @@ -0,0 +1,321 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Designware HDMI CEC driver + * + * Copyright (C) 2015-2017 Russell King. + */ +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/sched.h> +#include <linux/slab.h> + +#include <drm/drm_edid.h> + +#include <media/cec.h> +#include <media/cec-notifier.h> + +#include "dw-hdmi-cec.h" + +enum { + HDMI_IH_CEC_STAT0 = 0x0106, + HDMI_IH_MUTE_CEC_STAT0 = 0x0186, + + HDMI_CEC_CTRL = 0x7d00, + CEC_CTRL_START = BIT(0), + CEC_CTRL_FRAME_TYP = 3 << 1, + CEC_CTRL_RETRY = 0 << 1, + CEC_CTRL_NORMAL = 1 << 1, + CEC_CTRL_IMMED = 2 << 1, + + HDMI_CEC_STAT = 0x7d01, + CEC_STAT_DONE = BIT(0), + CEC_STAT_EOM = BIT(1), + CEC_STAT_NACK = BIT(2), + CEC_STAT_ARBLOST = BIT(3), + CEC_STAT_ERROR_INIT = BIT(4), + CEC_STAT_ERROR_FOLL = BIT(5), + CEC_STAT_WAKEUP = BIT(6), + + HDMI_CEC_MASK = 0x7d02, + HDMI_CEC_POLARITY = 0x7d03, + HDMI_CEC_INT = 0x7d04, + HDMI_CEC_ADDR_L = 0x7d05, + HDMI_CEC_ADDR_H = 0x7d06, + HDMI_CEC_TX_CNT = 0x7d07, + HDMI_CEC_RX_CNT = 0x7d08, + HDMI_CEC_TX_DATA0 = 0x7d10, + HDMI_CEC_RX_DATA0 = 0x7d20, + HDMI_CEC_LOCK = 0x7d30, + HDMI_CEC_WKUPCTRL = 0x7d31, +}; + +struct dw_hdmi_cec { + struct dw_hdmi *hdmi; + const struct dw_hdmi_cec_ops *ops; + u32 addresses; + struct cec_adapter *adap; + struct cec_msg rx_msg; + unsigned int tx_status; + bool tx_done; + bool rx_done; + struct cec_notifier *notify; + int irq; +}; + +static void dw_hdmi_write(struct dw_hdmi_cec *cec, u8 val, int offset) +{ + cec->ops->write(cec->hdmi, val, offset); +} + +static u8 dw_hdmi_read(struct dw_hdmi_cec *cec, int offset) +{ + return cec->ops->read(cec->hdmi, offset); +} + +static int dw_hdmi_cec_log_addr(struct cec_adapter *adap, u8 logical_addr) +{ + struct dw_hdmi_cec *cec = cec_get_drvdata(adap); + + if (logical_addr == CEC_LOG_ADDR_INVALID) + cec->addresses = 0; + else + cec->addresses |= BIT(logical_addr) | BIT(15); + + dw_hdmi_write(cec, cec->addresses & 255, HDMI_CEC_ADDR_L); + dw_hdmi_write(cec, cec->addresses >> 8, HDMI_CEC_ADDR_H); + + return 0; +} + +static int dw_hdmi_cec_transmit(struct cec_adapter *adap, u8 attempts, + u32 signal_free_time, struct cec_msg *msg) +{ + struct dw_hdmi_cec *cec = cec_get_drvdata(adap); + unsigned int i, ctrl; + + switch (signal_free_time) { + case CEC_SIGNAL_FREE_TIME_RETRY: + ctrl = CEC_CTRL_RETRY; + break; + case CEC_SIGNAL_FREE_TIME_NEW_INITIATOR: + default: + ctrl = CEC_CTRL_NORMAL; + break; + case CEC_SIGNAL_FREE_TIME_NEXT_XFER: + ctrl = CEC_CTRL_IMMED; + break; + } + + for (i = 0; i < msg->len; i++) + dw_hdmi_write(cec, msg->msg[i], HDMI_CEC_TX_DATA0 + i); + + dw_hdmi_write(cec, msg->len, HDMI_CEC_TX_CNT); + dw_hdmi_write(cec, ctrl | CEC_CTRL_START, HDMI_CEC_CTRL); + + return 0; +} + +static irqreturn_t dw_hdmi_cec_hardirq(int irq, void *data) +{ + struct cec_adapter *adap = data; + struct dw_hdmi_cec *cec = cec_get_drvdata(adap); + unsigned int stat = dw_hdmi_read(cec, HDMI_IH_CEC_STAT0); + irqreturn_t ret = IRQ_HANDLED; + + if (stat == 0) + return IRQ_NONE; + + dw_hdmi_write(cec, stat, HDMI_IH_CEC_STAT0); + + if (stat & CEC_STAT_ERROR_INIT) { + cec->tx_status = CEC_TX_STATUS_ERROR; + cec->tx_done = true; + ret = IRQ_WAKE_THREAD; + } else if (stat & CEC_STAT_DONE) { + cec->tx_status = CEC_TX_STATUS_OK; + cec->tx_done = true; + ret = IRQ_WAKE_THREAD; + } else if (stat & CEC_STAT_NACK) { + cec->tx_status = CEC_TX_STATUS_NACK; + cec->tx_done = true; + ret = IRQ_WAKE_THREAD; + } + + if (stat & CEC_STAT_EOM) { + unsigned int len, i; + + len = dw_hdmi_read(cec, HDMI_CEC_RX_CNT); + if (len > sizeof(cec->rx_msg.msg)) + len = sizeof(cec->rx_msg.msg); + + for (i = 0; i < len; i++) + cec->rx_msg.msg[i] = + dw_hdmi_read(cec, HDMI_CEC_RX_DATA0 + i); + + dw_hdmi_write(cec, 0, HDMI_CEC_LOCK); + + cec->rx_msg.len = len; + smp_wmb(); + cec->rx_done = true; + + ret = IRQ_WAKE_THREAD; + } + + return ret; +} + +static irqreturn_t dw_hdmi_cec_thread(int irq, void *data) +{ + struct cec_adapter *adap = data; + struct dw_hdmi_cec *cec = cec_get_drvdata(adap); + + if (cec->tx_done) { + cec->tx_done = false; + cec_transmit_attempt_done(adap, cec->tx_status); + } + if (cec->rx_done) { + cec->rx_done = false; + smp_rmb(); + cec_received_msg(adap, &cec->rx_msg); + } + return IRQ_HANDLED; +} + +static int dw_hdmi_cec_enable(struct cec_adapter *adap, bool enable) +{ + struct dw_hdmi_cec *cec = cec_get_drvdata(adap); + + if (!enable) { + dw_hdmi_write(cec, ~0, HDMI_CEC_MASK); + dw_hdmi_write(cec, ~0, HDMI_IH_MUTE_CEC_STAT0); + dw_hdmi_write(cec, 0, HDMI_CEC_POLARITY); + + cec->ops->disable(cec->hdmi); + } else { + unsigned int irqs; + + dw_hdmi_write(cec, 0, HDMI_CEC_CTRL); + dw_hdmi_write(cec, ~0, HDMI_IH_CEC_STAT0); + dw_hdmi_write(cec, 0, HDMI_CEC_LOCK); + + dw_hdmi_cec_log_addr(cec->adap, CEC_LOG_ADDR_INVALID); + + cec->ops->enable(cec->hdmi); + + irqs = CEC_STAT_ERROR_INIT | CEC_STAT_NACK | CEC_STAT_EOM | + CEC_STAT_DONE; + dw_hdmi_write(cec, irqs, HDMI_CEC_POLARITY); + dw_hdmi_write(cec, ~irqs, HDMI_CEC_MASK); + dw_hdmi_write(cec, ~irqs, HDMI_IH_MUTE_CEC_STAT0); + } + return 0; +} + +static const struct cec_adap_ops dw_hdmi_cec_ops = { + .adap_enable = dw_hdmi_cec_enable, + .adap_log_addr = dw_hdmi_cec_log_addr, + .adap_transmit = dw_hdmi_cec_transmit, +}; + +static void dw_hdmi_cec_del(void *data) +{ + struct dw_hdmi_cec *cec = data; + + cec_delete_adapter(cec->adap); +} + +static int dw_hdmi_cec_probe(struct platform_device *pdev) +{ + struct dw_hdmi_cec_data *data = dev_get_platdata(&pdev->dev); + struct dw_hdmi_cec *cec; + int ret; + + if (!data) + return -ENXIO; + + /* + * Our device is just a convenience - we want to link to the real + * hardware device here, so that userspace can see the association + * between the HDMI hardware and its associated CEC chardev. + */ + cec = devm_kzalloc(&pdev->dev, sizeof(*cec), GFP_KERNEL); + if (!cec) + return -ENOMEM; + + cec->irq = data->irq; + cec->ops = data->ops; + cec->hdmi = data->hdmi; + + platform_set_drvdata(pdev, cec); + + dw_hdmi_write(cec, 0, HDMI_CEC_TX_CNT); + dw_hdmi_write(cec, ~0, HDMI_CEC_MASK); + dw_hdmi_write(cec, ~0, HDMI_IH_MUTE_CEC_STAT0); + dw_hdmi_write(cec, 0, HDMI_CEC_POLARITY); + + cec->adap = cec_allocate_adapter(&dw_hdmi_cec_ops, cec, "dw_hdmi", + CEC_CAP_DEFAULTS | + CEC_CAP_CONNECTOR_INFO, + CEC_MAX_LOG_ADDRS); + if (IS_ERR(cec->adap)) + return PTR_ERR(cec->adap); + + /* override the module pointer */ + cec->adap->owner = THIS_MODULE; + + ret = devm_add_action_or_reset(&pdev->dev, dw_hdmi_cec_del, cec); + if (ret) + return ret; + + ret = devm_request_threaded_irq(&pdev->dev, cec->irq, + dw_hdmi_cec_hardirq, + dw_hdmi_cec_thread, IRQF_SHARED, + "dw-hdmi-cec", cec->adap); + if (ret < 0) + return ret; + + cec->notify = cec_notifier_cec_adap_register(pdev->dev.parent, + NULL, cec->adap); + if (!cec->notify) + return -ENOMEM; + + ret = cec_register_adapter(cec->adap, pdev->dev.parent); + if (ret < 0) { + cec_notifier_cec_adap_unregister(cec->notify, cec->adap); + return ret; + } + + /* + * CEC documentation says we must not call cec_delete_adapter + * after a successful call to cec_register_adapter(). + */ + devm_remove_action(&pdev->dev, dw_hdmi_cec_del, cec); + + return 0; +} + +static int dw_hdmi_cec_remove(struct platform_device *pdev) +{ + struct dw_hdmi_cec *cec = platform_get_drvdata(pdev); + + cec_notifier_cec_adap_unregister(cec->notify, cec->adap); + cec_unregister_adapter(cec->adap); + + return 0; +} + +static struct platform_driver dw_hdmi_cec_driver = { + .probe = dw_hdmi_cec_probe, + .remove = dw_hdmi_cec_remove, + .driver = { + .name = "dw-hdmi-cec", + }, +}; +module_platform_driver(dw_hdmi_cec_driver); + +MODULE_AUTHOR("Russell King <rmk+kernel@armlinux.org.uk>"); +MODULE_DESCRIPTION("Synopsys Designware HDMI CEC driver for i.MX"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS(PLATFORM_MODULE_PREFIX "dw-hdmi-cec"); |