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path: root/drivers/media/cec/platform/cec-gpio/cec-gpio.c
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Diffstat (limited to 'drivers/media/cec/platform/cec-gpio/cec-gpio.c')
-rw-r--r--drivers/media/cec/platform/cec-gpio/cec-gpio.c302
1 files changed, 302 insertions, 0 deletions
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 000000000000..c8c4efc83f5f
--- /dev/null
+++ b/drivers/media/cec/platform/cec-gpio/cec-gpio.c
@@ -0,0 +1,302 @@
+// 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 void cec_gpio_free(struct cec_adapter *adap)
+{
+ cec_gpio_disable_irq(adap);
+}
+
+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,
+ .free = cec_gpio_free,
+ .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,
+ cec->adap->name, cec);
+ if (ret)
+ goto del_adap;
+
+ cec_gpio_disable_irq(cec->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 int 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);
+ return 0;
+}
+
+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 = 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");