openwrt/target/linux/ath79/patches-5.4/0003-leds-add-reset-control...

187 lines
5.0 KiB
Diff

From ecbd9c87f073f097d9fe56390353e64e963e866a Mon Sep 17 00:00:00 2001
From: John Crispin <john@phrozen.org>
Date: Tue, 6 Mar 2018 10:03:03 +0100
Subject: [PATCH 03/27] leds: add reset-controller based driver
Signed-off-by: John Crispin <john@phrozen.org>
---
drivers/leds/Kconfig | 11 ++++
drivers/leds/Makefile | 1 +
drivers/leds/leds-reset.c | 137 ++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 149 insertions(+)
create mode 100644 drivers/leds/leds-reset.c
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -823,6 +823,17 @@ config LEDS_LM36274
Say Y to enable the LM36274 LED driver for TI LMU devices.
This supports the LED device LM36274.
+config LEDS_RESET
+ tristate "LED support for reset-controller API"
+ depends on LEDS_CLASS
+ depends on RESET_CONTROLLER
+ help
+ This option enables support for LEDs connected to pins driven by reset
+ controllers. Yes, DNI actual built HW like that.
+
+ To compile this driver as a module, choose M here: the module
+ will be called leds-reset.
+
comment "LED Triggers"
source "drivers/leds/trigger/Kconfig"
--- /dev/null
+++ b/drivers/leds/leds-reset.c
@@ -0,0 +1,140 @@
+/*
+ * Copyright (C) 2018 John Crispin <john@phrozen.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+#include <linux/err.h>
+#include <linux/reset.h>
+#include <linux/kernel.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+
+struct reset_led_data {
+ struct led_classdev cdev;
+ struct reset_control *rst;
+};
+
+static inline struct reset_led_data *
+ cdev_to_reset_led_data(struct led_classdev *led_cdev)
+{
+ return container_of(led_cdev, struct reset_led_data, cdev);
+}
+
+static void reset_led_set(struct led_classdev *led_cdev,
+ enum led_brightness value)
+{
+ struct reset_led_data *led_dat = cdev_to_reset_led_data(led_cdev);
+
+ if (value == LED_OFF)
+ reset_control_assert(led_dat->rst);
+ else
+ reset_control_deassert(led_dat->rst);
+}
+
+struct reset_leds_priv {
+ int num_leds;
+ struct reset_led_data leds[];
+};
+
+static inline int sizeof_reset_leds_priv(int num_leds)
+{
+ return sizeof(struct reset_leds_priv) +
+ (sizeof(struct reset_led_data) * num_leds);
+}
+
+static struct reset_leds_priv *reset_leds_create(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct fwnode_handle *child;
+ struct reset_leds_priv *priv;
+ int count, ret;
+
+ count = device_get_child_node_count(dev);
+ if (!count)
+ return ERR_PTR(-ENODEV);
+
+ priv = devm_kzalloc(dev, sizeof_reset_leds_priv(count), GFP_KERNEL);
+ if (!priv)
+ return ERR_PTR(-ENOMEM);
+
+ device_for_each_child_node(dev, child) {
+ struct reset_led_data *led = &priv->leds[priv->num_leds];
+ struct device_node *np = to_of_node(child);
+
+ ret = fwnode_property_read_string(child, "label", &led->cdev.name);
+ if (!led->cdev.name) {
+ fwnode_handle_put(child);
+ return ERR_PTR(-EINVAL);
+ }
+ led->rst = __of_reset_control_get(np, NULL, 0, 0, 0, true);
+ if (IS_ERR(led->rst))
+ return ERR_PTR(-EINVAL);
+
+ fwnode_property_read_string(child, "linux,default-trigger",
+ &led->cdev.default_trigger);
+
+ led->cdev.brightness_set = reset_led_set;
+ ret = devm_led_classdev_register(&pdev->dev, &led->cdev);
+ if (ret < 0)
+ return ERR_PTR(ret);
+ led->cdev.dev->of_node = np;
+ priv->num_leds++;
+ }
+
+ return priv;
+}
+
+static const struct of_device_id of_reset_leds_match[] = {
+ { .compatible = "reset-leds", },
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, of_reset_leds_match);
+
+static int reset_led_probe(struct platform_device *pdev)
+{
+ struct reset_leds_priv *priv;
+
+ priv = reset_leds_create(pdev);
+ if (IS_ERR(priv))
+ return PTR_ERR(priv);
+
+ platform_set_drvdata(pdev, priv);
+
+ return 0;
+}
+
+static void reset_led_shutdown(struct platform_device *pdev)
+{
+ struct reset_leds_priv *priv = platform_get_drvdata(pdev);
+ int i;
+
+ for (i = 0; i < priv->num_leds; i++) {
+ struct reset_led_data *led = &priv->leds[i];
+
+ if (!(led->cdev.flags & LED_RETAIN_AT_SHUTDOWN))
+ reset_led_set(&led->cdev, LED_OFF);
+ }
+}
+
+static struct platform_driver reset_led_driver = {
+ .probe = reset_led_probe,
+ .shutdown = reset_led_shutdown,
+ .driver = {
+ .name = "leds-reset",
+ .of_match_table = of_reset_leds_match,
+ },
+};
+
+module_platform_driver(reset_led_driver);
+
+MODULE_AUTHOR("John Crispin <john@phrozen.org>");
+MODULE_DESCRIPTION("reset controller LED driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:leds-reset");
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -85,6 +85,7 @@ obj-$(CONFIG_LEDS_LM3601X) += leds-lm36
obj-$(CONFIG_LEDS_TI_LMU_COMMON) += leds-ti-lmu-common.o
obj-$(CONFIG_LEDS_LM3697) += leds-lm3697.o
obj-$(CONFIG_LEDS_LM36274) += leds-lm36274.o
+obj-$(CONFIG_LEDS_RESET) += leds-reset.o
# LED SPI Drivers
obj-$(CONFIG_LEDS_CR0014114) += leds-cr0014114.o