diff options
Diffstat (limited to 'drivers/media/platform/s5p-cec/s5p_cec.c')
-rw-r--r-- | drivers/media/platform/s5p-cec/s5p_cec.c | 312 |
1 files changed, 312 insertions, 0 deletions
diff --git a/drivers/media/platform/s5p-cec/s5p_cec.c b/drivers/media/platform/s5p-cec/s5p_cec.c new file mode 100644 index 000000000..3032247c6 --- /dev/null +++ b/drivers/media/platform/s5p-cec/s5p_cec.c @@ -0,0 +1,312 @@ +/* drivers/media/platform/s5p-cec/s5p_cec.c + * + * Samsung S5P CEC driver + * + * Copyright (c) 2014 Samsung Electronics Co., Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This driver is based on the "cec interface driver for exynos soc" by + * SangPil Moon. + */ + +#include <linux/clk.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/timer.h> +#include <linux/workqueue.h> +#include <media/cec.h> +#include <media/cec-notifier.h> + +#include "exynos_hdmi_cec.h" +#include "regs-cec.h" +#include "s5p_cec.h" + +#define CEC_NAME "s5p-cec" + +static int debug; +module_param(debug, int, 0644); +MODULE_PARM_DESC(debug, "debug level (0-2)"); + +static int s5p_cec_adap_enable(struct cec_adapter *adap, bool enable) +{ + struct s5p_cec_dev *cec = cec_get_drvdata(adap); + + if (enable) { + pm_runtime_get_sync(cec->dev); + + s5p_cec_reset(cec); + + s5p_cec_set_divider(cec); + s5p_cec_threshold(cec); + + s5p_cec_unmask_tx_interrupts(cec); + s5p_cec_unmask_rx_interrupts(cec); + s5p_cec_enable_rx(cec); + } else { + s5p_cec_mask_tx_interrupts(cec); + s5p_cec_mask_rx_interrupts(cec); + pm_runtime_put(cec->dev); + } + + return 0; +} + +static int s5p_cec_adap_log_addr(struct cec_adapter *adap, u8 addr) +{ + struct s5p_cec_dev *cec = cec_get_drvdata(adap); + + s5p_cec_set_addr(cec, addr); + return 0; +} + +static int s5p_cec_adap_transmit(struct cec_adapter *adap, u8 attempts, + u32 signal_free_time, struct cec_msg *msg) +{ + struct s5p_cec_dev *cec = cec_get_drvdata(adap); + + /* + * Unclear if 0 retries are allowed by the hardware, so have 1 as + * the minimum. + */ + s5p_cec_copy_packet(cec, msg->msg, msg->len, max(1, attempts - 1)); + return 0; +} + +static irqreturn_t s5p_cec_irq_handler(int irq, void *priv) +{ + struct s5p_cec_dev *cec = priv; + u32 status = 0; + + status = s5p_cec_get_status(cec); + + dev_dbg(cec->dev, "irq received\n"); + + if (status & CEC_STATUS_TX_DONE) { + if (status & CEC_STATUS_TX_NACK) { + dev_dbg(cec->dev, "CEC_STATUS_TX_NACK set\n"); + cec->tx = STATE_NACK; + } else if (status & CEC_STATUS_TX_ERROR) { + dev_dbg(cec->dev, "CEC_STATUS_TX_ERROR set\n"); + cec->tx = STATE_ERROR; + } else { + dev_dbg(cec->dev, "CEC_STATUS_TX_DONE\n"); + cec->tx = STATE_DONE; + } + s5p_clr_pending_tx(cec); + } + + if (status & CEC_STATUS_RX_DONE) { + if (status & CEC_STATUS_RX_ERROR) { + dev_dbg(cec->dev, "CEC_STATUS_RX_ERROR set\n"); + s5p_cec_rx_reset(cec); + s5p_cec_enable_rx(cec); + } else { + dev_dbg(cec->dev, "CEC_STATUS_RX_DONE set\n"); + if (cec->rx != STATE_IDLE) + dev_dbg(cec->dev, "Buffer overrun (worker did not process previous message)\n"); + cec->rx = STATE_BUSY; + cec->msg.len = status >> 24; + cec->msg.rx_status = CEC_RX_STATUS_OK; + s5p_cec_get_rx_buf(cec, cec->msg.len, + cec->msg.msg); + cec->rx = STATE_DONE; + s5p_cec_enable_rx(cec); + } + /* Clear interrupt pending bit */ + s5p_clr_pending_rx(cec); + } + return IRQ_WAKE_THREAD; +} + +static irqreturn_t s5p_cec_irq_handler_thread(int irq, void *priv) +{ + struct s5p_cec_dev *cec = priv; + + dev_dbg(cec->dev, "irq processing thread\n"); + switch (cec->tx) { + case STATE_DONE: + cec_transmit_done(cec->adap, CEC_TX_STATUS_OK, 0, 0, 0, 0); + cec->tx = STATE_IDLE; + break; + case STATE_NACK: + cec_transmit_done(cec->adap, + CEC_TX_STATUS_MAX_RETRIES | CEC_TX_STATUS_NACK, + 0, 1, 0, 0); + cec->tx = STATE_IDLE; + break; + case STATE_ERROR: + cec_transmit_done(cec->adap, + CEC_TX_STATUS_MAX_RETRIES | CEC_TX_STATUS_ERROR, + 0, 0, 0, 1); + cec->tx = STATE_IDLE; + break; + case STATE_BUSY: + dev_err(cec->dev, "state set to busy, this should not occur here\n"); + break; + default: + break; + } + + switch (cec->rx) { + case STATE_DONE: + cec_received_msg(cec->adap, &cec->msg); + cec->rx = STATE_IDLE; + break; + default: + break; + } + + return IRQ_HANDLED; +} + +static const struct cec_adap_ops s5p_cec_adap_ops = { + .adap_enable = s5p_cec_adap_enable, + .adap_log_addr = s5p_cec_adap_log_addr, + .adap_transmit = s5p_cec_adap_transmit, +}; + +static int s5p_cec_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np; + struct platform_device *hdmi_dev; + struct resource *res; + struct s5p_cec_dev *cec; + bool needs_hpd = of_property_read_bool(pdev->dev.of_node, "needs-hpd"); + int ret; + + 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(*cec), GFP_KERNEL); + if (!cec) + return -ENOMEM; + + cec->dev = dev; + + cec->irq = platform_get_irq(pdev, 0); + if (cec->irq < 0) + return cec->irq; + + ret = devm_request_threaded_irq(dev, cec->irq, s5p_cec_irq_handler, + s5p_cec_irq_handler_thread, 0, pdev->name, cec); + if (ret) + return ret; + + cec->clk = devm_clk_get(dev, "hdmicec"); + if (IS_ERR(cec->clk)) + return PTR_ERR(cec->clk); + + cec->pmu = syscon_regmap_lookup_by_phandle(dev->of_node, + "samsung,syscon-phandle"); + if (IS_ERR(cec->pmu)) + return -EPROBE_DEFER; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + cec->reg = devm_ioremap_resource(dev, res); + if (IS_ERR(cec->reg)) + return PTR_ERR(cec->reg); + + cec->notifier = cec_notifier_get(&hdmi_dev->dev); + if (cec->notifier == NULL) + return -ENOMEM; + + cec->adap = cec_allocate_adapter(&s5p_cec_adap_ops, cec, CEC_NAME, + CEC_CAP_DEFAULTS | (needs_hpd ? CEC_CAP_NEEDS_HPD : 0), 1); + ret = PTR_ERR_OR_ZERO(cec->adap); + if (ret) + return ret; + + ret = cec_register_adapter(cec->adap, &pdev->dev); + if (ret) + goto err_delete_adapter; + + cec_register_cec_notifier(cec->adap, cec->notifier); + + platform_set_drvdata(pdev, cec); + pm_runtime_enable(dev); + + dev_dbg(dev, "successfully probed\n"); + return 0; + +err_delete_adapter: + cec_delete_adapter(cec->adap); + return ret; +} + +static int s5p_cec_remove(struct platform_device *pdev) +{ + struct s5p_cec_dev *cec = platform_get_drvdata(pdev); + + cec_unregister_adapter(cec->adap); + cec_notifier_put(cec->notifier); + pm_runtime_disable(&pdev->dev); + return 0; +} + +static int __maybe_unused s5p_cec_runtime_suspend(struct device *dev) +{ + struct s5p_cec_dev *cec = dev_get_drvdata(dev); + + clk_disable_unprepare(cec->clk); + return 0; +} + +static int __maybe_unused s5p_cec_runtime_resume(struct device *dev) +{ + struct s5p_cec_dev *cec = dev_get_drvdata(dev); + int ret; + + ret = clk_prepare_enable(cec->clk); + if (ret < 0) + return ret; + return 0; +} + +static const struct dev_pm_ops s5p_cec_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, + pm_runtime_force_resume) + SET_RUNTIME_PM_OPS(s5p_cec_runtime_suspend, s5p_cec_runtime_resume, + NULL) +}; + +static const struct of_device_id s5p_cec_match[] = { + { + .compatible = "samsung,s5p-cec", + }, + {}, +}; +MODULE_DEVICE_TABLE(of, s5p_cec_match); + +static struct platform_driver s5p_cec_pdrv = { + .probe = s5p_cec_probe, + .remove = s5p_cec_remove, + .driver = { + .name = CEC_NAME, + .of_match_table = s5p_cec_match, + .pm = &s5p_cec_pm_ops, + }, +}; + +module_platform_driver(s5p_cec_pdrv); + +MODULE_AUTHOR("Kamil Debski <kamil@wypas.org>"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Samsung S5P CEC driver"); |