2 files changed, 295 insertions, 0 deletions

diff --git a/drivers/media/cec/platform/cec-gpio/Makefile b/drivers/media/cec/platform/cec-gpio/Makefile
new file mode 100644
index 0000000000..a40c621dbd
--- /dev/null
+++ b/drivers/media/cec/platform/cec-gpio/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_CEC_GPIO) += cec-gpio.o
diff --git a/drivers/media/cec/platform/cec-gpio/cec-gpio.c b/drivers/media/cec/platform/cec-gpio/cec-gpio.c
new file mode 100644
index 0000000000..98dacb0919
--- /dev/null
+++ b/drivers/media/cec/platform/cec-gpio/cec-gpio.c
@@ -0,0 +1,293 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2017 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
+ */
+
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/gpio/consumer.h>
+#include <media/cec-notifier.h>
+#include <media/cec-pin.h>
+
+struct cec_gpio {
+	struct cec_adapter	*adap;
+	struct cec_notifier	*notifier;
+	struct device		*dev;
+
+	struct gpio_desc	*cec_gpio;
+	int			cec_irq;
+	bool			cec_is_low;
+
+	struct gpio_desc	*hpd_gpio;
+	int			hpd_irq;
+	bool			hpd_is_high;
+	ktime_t			hpd_ts;
+
+	struct gpio_desc	*v5_gpio;
+	int			v5_irq;
+	bool			v5_is_high;
+	ktime_t			v5_ts;
+};
+
+static int cec_gpio_read(struct cec_adapter *adap)
+{
+	struct cec_gpio *cec = cec_get_drvdata(adap);
+
+	if (cec->cec_is_low)
+		return 0;
+	return gpiod_get_value(cec->cec_gpio);
+}
+
+static void cec_gpio_high(struct cec_adapter *adap)
+{
+	struct cec_gpio *cec = cec_get_drvdata(adap);
+
+	if (!cec->cec_is_low)
+		return;
+	cec->cec_is_low = false;
+	gpiod_set_value(cec->cec_gpio, 1);
+}
+
+static void cec_gpio_low(struct cec_adapter *adap)
+{
+	struct cec_gpio *cec = cec_get_drvdata(adap);
+
+	if (cec->cec_is_low)
+		return;
+	cec->cec_is_low = true;
+	gpiod_set_value(cec->cec_gpio, 0);
+}
+
+static irqreturn_t cec_hpd_gpio_irq_handler_thread(int irq, void *priv)
+{
+	struct cec_gpio *cec = priv;
+
+	cec_queue_pin_hpd_event(cec->adap, cec->hpd_is_high, cec->hpd_ts);
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t cec_5v_gpio_irq_handler(int irq, void *priv)
+{
+	struct cec_gpio *cec = priv;
+	int val = gpiod_get_value(cec->v5_gpio);
+	bool is_high = val > 0;
+
+	if (val < 0 || is_high == cec->v5_is_high)
+		return IRQ_HANDLED;
+	cec->v5_ts = ktime_get();
+	cec->v5_is_high = is_high;
+	return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t cec_5v_gpio_irq_handler_thread(int irq, void *priv)
+{
+	struct cec_gpio *cec = priv;
+
+	cec_queue_pin_5v_event(cec->adap, cec->v5_is_high, cec->v5_ts);
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t cec_hpd_gpio_irq_handler(int irq, void *priv)
+{
+	struct cec_gpio *cec = priv;
+	int val = gpiod_get_value(cec->hpd_gpio);
+	bool is_high = val > 0;
+
+	if (val < 0 || is_high == cec->hpd_is_high)
+		return IRQ_HANDLED;
+	cec->hpd_ts = ktime_get();
+	cec->hpd_is_high = is_high;
+	return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t cec_gpio_irq_handler(int irq, void *priv)
+{
+	struct cec_gpio *cec = priv;
+	int val = gpiod_get_value(cec->cec_gpio);
+
+	if (val >= 0)
+		cec_pin_changed(cec->adap, val > 0);
+	return IRQ_HANDLED;
+}
+
+static bool cec_gpio_enable_irq(struct cec_adapter *adap)
+{
+	struct cec_gpio *cec = cec_get_drvdata(adap);
+
+	enable_irq(cec->cec_irq);
+	return true;
+}
+
+static void cec_gpio_disable_irq(struct cec_adapter *adap)
+{
+	struct cec_gpio *cec = cec_get_drvdata(adap);
+
+	disable_irq(cec->cec_irq);
+}
+
+static void cec_gpio_status(struct cec_adapter *adap, struct seq_file *file)
+{
+	struct cec_gpio *cec = cec_get_drvdata(adap);
+
+	seq_printf(file, "mode: %s\n", cec->cec_is_low ? "low-drive" : "read");
+	seq_printf(file, "using irq: %d\n", cec->cec_irq);
+	if (cec->hpd_gpio)
+		seq_printf(file, "hpd: %s\n",
+			   cec->hpd_is_high ? "high" : "low");
+	if (cec->v5_gpio)
+		seq_printf(file, "5V: %s\n",
+			   cec->v5_is_high ? "high" : "low");
+}
+
+static int cec_gpio_read_hpd(struct cec_adapter *adap)
+{
+	struct cec_gpio *cec = cec_get_drvdata(adap);
+
+	if (!cec->hpd_gpio)
+		return -ENOTTY;
+	return gpiod_get_value(cec->hpd_gpio);
+}
+
+static int cec_gpio_read_5v(struct cec_adapter *adap)
+{
+	struct cec_gpio *cec = cec_get_drvdata(adap);
+
+	if (!cec->v5_gpio)
+		return -ENOTTY;
+	return gpiod_get_value(cec->v5_gpio);
+}
+
+static const struct cec_pin_ops cec_gpio_pin_ops = {
+	.read = cec_gpio_read,
+	.low = cec_gpio_low,
+	.high = cec_gpio_high,
+	.enable_irq = cec_gpio_enable_irq,
+	.disable_irq = cec_gpio_disable_irq,
+	.status = cec_gpio_status,
+	.read_hpd = cec_gpio_read_hpd,
+	.read_5v = cec_gpio_read_5v,
+};
+
+static int cec_gpio_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device *hdmi_dev;
+	struct cec_gpio *cec;
+	u32 caps = CEC_CAP_DEFAULTS | CEC_CAP_MONITOR_ALL | CEC_CAP_MONITOR_PIN;
+	int ret;
+
+	hdmi_dev = cec_notifier_parse_hdmi_phandle(dev);
+	if (PTR_ERR(hdmi_dev) == -EPROBE_DEFER)
+		return PTR_ERR(hdmi_dev);
+	if (IS_ERR(hdmi_dev))
+		caps |= CEC_CAP_PHYS_ADDR;
+
+	cec = devm_kzalloc(dev, sizeof(*cec), GFP_KERNEL);
+	if (!cec)
+		return -ENOMEM;
+
+	cec->dev = dev;
+
+	cec->cec_gpio = devm_gpiod_get(dev, "cec", GPIOD_OUT_HIGH_OPEN_DRAIN);
+	if (IS_ERR(cec->cec_gpio))
+		return PTR_ERR(cec->cec_gpio);
+	cec->cec_irq = gpiod_to_irq(cec->cec_gpio);
+
+	cec->hpd_gpio = devm_gpiod_get_optional(dev, "hpd", GPIOD_IN);
+	if (IS_ERR(cec->hpd_gpio))
+		return PTR_ERR(cec->hpd_gpio);
+
+	cec->v5_gpio = devm_gpiod_get_optional(dev, "v5", GPIOD_IN);
+	if (IS_ERR(cec->v5_gpio))
+		return PTR_ERR(cec->v5_gpio);
+
+	cec->adap = cec_pin_allocate_adapter(&cec_gpio_pin_ops,
+					     cec, pdev->name, caps);
+	if (IS_ERR(cec->adap))
+		return PTR_ERR(cec->adap);
+
+	ret = devm_request_irq(dev, cec->cec_irq, cec_gpio_irq_handler,
+			       IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_NO_AUTOEN,
+			       cec->adap->name, cec);
+	if (ret)
+		goto del_adap;
+
+	if (cec->hpd_gpio) {
+		cec->hpd_irq = gpiod_to_irq(cec->hpd_gpio);
+		ret = devm_request_threaded_irq(dev, cec->hpd_irq,
+			cec_hpd_gpio_irq_handler,
+			cec_hpd_gpio_irq_handler_thread,
+			IRQF_ONESHOT |
+			IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
+			"hpd-gpio", cec);
+		if (ret)
+			goto del_adap;
+	}
+
+	if (cec->v5_gpio) {
+		cec->v5_irq = gpiod_to_irq(cec->v5_gpio);
+		ret = devm_request_threaded_irq(dev, cec->v5_irq,
+			cec_5v_gpio_irq_handler,
+			cec_5v_gpio_irq_handler_thread,
+			IRQF_ONESHOT |
+			IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
+			"v5-gpio", cec);
+		if (ret)
+			goto del_adap;
+	}
+
+	if (!IS_ERR(hdmi_dev)) {
+		cec->notifier = cec_notifier_cec_adap_register(hdmi_dev, NULL,
+							       cec->adap);
+		if (!cec->notifier) {
+			ret = -ENOMEM;
+			goto del_adap;
+		}
+	}
+
+	ret = cec_register_adapter(cec->adap, &pdev->dev);
+	if (ret)
+		goto unreg_notifier;
+
+	platform_set_drvdata(pdev, cec);
+	return 0;
+
+unreg_notifier:
+	cec_notifier_cec_adap_unregister(cec->notifier, cec->adap);
+del_adap:
+	cec_delete_adapter(cec->adap);
+	return ret;
+}
+
+static void cec_gpio_remove(struct platform_device *pdev)
+{
+	struct cec_gpio *cec = platform_get_drvdata(pdev);
+
+	cec_notifier_cec_adap_unregister(cec->notifier, cec->adap);
+	cec_unregister_adapter(cec->adap);
+}
+
+static const struct of_device_id cec_gpio_match[] = {
+	{
+		.compatible	= "cec-gpio",
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, cec_gpio_match);
+
+static struct platform_driver cec_gpio_pdrv = {
+	.probe	= cec_gpio_probe,
+	.remove_new = cec_gpio_remove,
+	.driver = {
+		.name		= "cec-gpio",
+		.of_match_table	= cec_gpio_match,
+	},
+};
+
+module_platform_driver(cec_gpio_pdrv);
+
+MODULE_AUTHOR("Hans Verkuil <hans.verkuil@cisco.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("CEC GPIO driver");