ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/drivers/pps/clients/pps-gpio.c b/marvell/linux/drivers/pps/clients/pps-gpio.c
new file mode 100644
index 0000000..e0de1df
--- /dev/null
+++ b/marvell/linux/drivers/pps/clients/pps-gpio.c
@@ -0,0 +1,275 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * pps-gpio.c -- PPS client driver using GPIO
+ *
+ * Copyright (C) 2010 Ricardo Martins <rasm@fe.up.pt>
+ * Copyright (C) 2011 James Nuss <jamesnuss@nanometrics.ca>
+ */
+
+#define PPS_GPIO_NAME "pps-gpio"
+#define pr_fmt(fmt) PPS_GPIO_NAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/pps_kernel.h>
+#include <linux/pps-gpio.h>
+#include <linux/gpio/consumer.h>
+#include <linux/list.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
+#include <linux/timer.h>
+#include <linux/jiffies.h>
+
+/* Info for each registered platform device */
+struct pps_gpio_device_data {
+ int irq; /* IRQ used as PPS source */
+ struct pps_device *pps; /* PPS source device */
+ struct pps_source_info info; /* PPS source information */
+ struct gpio_desc *gpio_pin; /* GPIO port descriptors */
+ struct gpio_desc *echo_pin;
+ struct timer_list echo_timer; /* timer to reset echo active state */
+ bool assert_falling_edge;
+ bool capture_clear;
+ unsigned int echo_active_ms; /* PPS echo active duration */
+ unsigned long echo_timeout; /* timer timeout value in jiffies */
+};
+
+/*
+ * Report the PPS event
+ */
+
+static irqreturn_t pps_gpio_irq_handler(int irq, void *data)
+{
+ const struct pps_gpio_device_data *info;
+ struct pps_event_time ts;
+ int rising_edge;
+
+ /* Get the time stamp first */
+ pps_get_ts(&ts);
+
+ info = data;
+
+ rising_edge = gpiod_get_value(info->gpio_pin);
+ if ((rising_edge && !info->assert_falling_edge) ||
+ (!rising_edge && info->assert_falling_edge))
+ pps_event(info->pps, &ts, PPS_CAPTUREASSERT, data);
+ else if (info->capture_clear &&
+ ((rising_edge && info->assert_falling_edge) ||
+ (!rising_edge && !info->assert_falling_edge)))
+ pps_event(info->pps, &ts, PPS_CAPTURECLEAR, data);
+
+ return IRQ_HANDLED;
+}
+
+/* This function will only be called when an ECHO GPIO is defined */
+static void pps_gpio_echo(struct pps_device *pps, int event, void *data)
+{
+ /* add_timer() needs to write into info->echo_timer */
+ struct pps_gpio_device_data *info = data;
+
+ switch (event) {
+ case PPS_CAPTUREASSERT:
+ if (pps->params.mode & PPS_ECHOASSERT)
+ gpiod_set_value(info->echo_pin, 1);
+ break;
+
+ case PPS_CAPTURECLEAR:
+ if (pps->params.mode & PPS_ECHOCLEAR)
+ gpiod_set_value(info->echo_pin, 1);
+ break;
+ }
+
+ /* fire the timer */
+ if (info->pps->params.mode & (PPS_ECHOASSERT | PPS_ECHOCLEAR)) {
+ info->echo_timer.expires = jiffies + info->echo_timeout;
+ add_timer(&info->echo_timer);
+ }
+}
+
+/* Timer callback to reset the echo pin to the inactive state */
+static void pps_gpio_echo_timer_callback(struct timer_list *t)
+{
+ const struct pps_gpio_device_data *info;
+
+ info = from_timer(info, t, echo_timer);
+
+ gpiod_set_value(info->echo_pin, 0);
+}
+
+static int pps_gpio_setup(struct platform_device *pdev)
+{
+ struct pps_gpio_device_data *data = platform_get_drvdata(pdev);
+ struct device_node *np = pdev->dev.of_node;
+ int ret;
+ u32 value;
+
+ data->gpio_pin = devm_gpiod_get(&pdev->dev,
+ NULL, /* request "gpios" */
+ GPIOD_IN);
+ if (IS_ERR(data->gpio_pin)) {
+ dev_err(&pdev->dev,
+ "failed to request PPS GPIO\n");
+ return PTR_ERR(data->gpio_pin);
+ }
+
+ data->echo_pin = devm_gpiod_get_optional(&pdev->dev,
+ "echo",
+ GPIOD_OUT_LOW);
+ if (data->echo_pin) {
+ if (IS_ERR(data->echo_pin)) {
+ dev_err(&pdev->dev, "failed to request ECHO GPIO\n");
+ return PTR_ERR(data->echo_pin);
+ }
+
+ ret = of_property_read_u32(np,
+ "echo-active-ms",
+ &value);
+ if (ret) {
+ dev_err(&pdev->dev,
+ "failed to get echo-active-ms from OF\n");
+ return ret;
+ }
+ data->echo_active_ms = value;
+ /* sanity check on echo_active_ms */
+ if (!data->echo_active_ms || data->echo_active_ms > 999) {
+ dev_err(&pdev->dev,
+ "echo-active-ms: %u - bad value from OF\n",
+ data->echo_active_ms);
+ return -EINVAL;
+ }
+ }
+
+ if (of_property_read_bool(np, "assert-falling-edge"))
+ data->assert_falling_edge = true;
+ return 0;
+}
+
+static unsigned long
+get_irqf_trigger_flags(const struct pps_gpio_device_data *data)
+{
+ unsigned long flags = data->assert_falling_edge ?
+ IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING;
+
+ if (data->capture_clear) {
+ flags |= ((flags & IRQF_TRIGGER_RISING) ?
+ IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING);
+ }
+
+ return flags;
+}
+
+static int pps_gpio_probe(struct platform_device *pdev)
+{
+ struct pps_gpio_device_data *data;
+ int ret;
+ int pps_default_params;
+ const struct pps_gpio_platform_data *pdata = pdev->dev.platform_data;
+
+ /* allocate space for device info */
+ data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+ platform_set_drvdata(pdev, data);
+
+ /* GPIO setup */
+ if (pdata) {
+ data->gpio_pin = pdata->gpio_pin;
+ data->echo_pin = pdata->echo_pin;
+
+ data->assert_falling_edge = pdata->assert_falling_edge;
+ data->capture_clear = pdata->capture_clear;
+ data->echo_active_ms = pdata->echo_active_ms;
+ } else {
+ ret = pps_gpio_setup(pdev);
+ if (ret)
+ return -EINVAL;
+ }
+
+ /* IRQ setup */
+ ret = gpiod_to_irq(data->gpio_pin);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to map GPIO to IRQ: %d\n", ret);
+ return -EINVAL;
+ }
+ data->irq = ret;
+
+ /* initialize PPS specific parts of the bookkeeping data structure. */
+ data->info.mode = PPS_CAPTUREASSERT | PPS_OFFSETASSERT |
+ PPS_ECHOASSERT | PPS_CANWAIT | PPS_TSFMT_TSPEC;
+ if (data->capture_clear)
+ data->info.mode |= PPS_CAPTURECLEAR | PPS_OFFSETCLEAR |
+ PPS_ECHOCLEAR;
+ data->info.owner = THIS_MODULE;
+ snprintf(data->info.name, PPS_MAX_NAME_LEN - 1, "%s.%d",
+ pdev->name, pdev->id);
+ if (data->echo_pin) {
+ data->info.echo = pps_gpio_echo;
+ data->echo_timeout = msecs_to_jiffies(data->echo_active_ms);
+ timer_setup(&data->echo_timer, pps_gpio_echo_timer_callback, 0);
+ }
+
+ /* register PPS source */
+ pps_default_params = PPS_CAPTUREASSERT | PPS_OFFSETASSERT;
+ if (data->capture_clear)
+ pps_default_params |= PPS_CAPTURECLEAR | PPS_OFFSETCLEAR;
+ data->pps = pps_register_source(&data->info, pps_default_params);
+ if (IS_ERR(data->pps)) {
+ dev_err(&pdev->dev, "failed to register IRQ %d as PPS source\n",
+ data->irq);
+ return PTR_ERR(data->pps);
+ }
+
+ /* register IRQ interrupt handler */
+ ret = devm_request_irq(&pdev->dev, data->irq, pps_gpio_irq_handler,
+ get_irqf_trigger_flags(data), data->info.name, data);
+ if (ret) {
+ pps_unregister_source(data->pps);
+ dev_err(&pdev->dev, "failed to acquire IRQ %d\n", data->irq);
+ return -EINVAL;
+ }
+
+ dev_info(data->pps->dev, "Registered IRQ %d as PPS source\n",
+ data->irq);
+
+ return 0;
+}
+
+static int pps_gpio_remove(struct platform_device *pdev)
+{
+ struct pps_gpio_device_data *data = platform_get_drvdata(pdev);
+
+ pps_unregister_source(data->pps);
+ if (data->echo_pin) {
+ del_timer_sync(&data->echo_timer);
+ /* reset echo pin in any case */
+ gpiod_set_value(data->echo_pin, 0);
+ }
+ dev_info(&pdev->dev, "removed IRQ %d as PPS source\n", data->irq);
+ return 0;
+}
+
+static const struct of_device_id pps_gpio_dt_ids[] = {
+ { .compatible = "pps-gpio", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, pps_gpio_dt_ids);
+
+static struct platform_driver pps_gpio_driver = {
+ .probe = pps_gpio_probe,
+ .remove = pps_gpio_remove,
+ .driver = {
+ .name = PPS_GPIO_NAME,
+ .of_match_table = pps_gpio_dt_ids,
+ },
+};
+
+module_platform_driver(pps_gpio_driver);
+MODULE_AUTHOR("Ricardo Martins <rasm@fe.up.pt>");
+MODULE_AUTHOR("James Nuss <jamesnuss@nanometrics.ca>");
+MODULE_DESCRIPTION("Use GPIO pin as PPS source");
+MODULE_LICENSE("GPL");
+MODULE_VERSION("1.2.0");