1 files changed, 251 insertions, 0 deletions
diff --git a/drivers/opp/debugfs.c b/drivers/opp/debugfs.c
new file mode 100644
index 000000000000..b03c03576a62
--- /dev/null
+++ b/drivers/opp/debugfs.c
@@ -0,0 +1,251 @@
+/*
+ * Generic OPP debugfs interface
+ *
+ * Copyright (C) 2015-2016 Viresh Kumar <viresh.kumar@linaro.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.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/limits.h>
+#include <linux/slab.h>
+
+#include "opp.h"
+
+static struct dentry *rootdir;
+
+static void opp_set_dev_name(const struct device *dev, char *name)
+{
+	if (dev->parent)
+		snprintf(name, NAME_MAX, "%s-%s", dev_name(dev->parent),
+			 dev_name(dev));
+	else
+		snprintf(name, NAME_MAX, "%s", dev_name(dev));
+}
+
+void opp_debug_remove_one(struct dev_pm_opp *opp)
+{
+	debugfs_remove_recursive(opp->dentry);
+}
+
+static bool opp_debug_create_supplies(struct dev_pm_opp *opp,
+				      struct opp_table *opp_table,
+				      struct dentry *pdentry)
+{
+	struct dentry *d;
+	int i;
+
+	for (i = 0; i < opp_table->regulator_count; i++) {
+		char name[15];
+
+		snprintf(name, sizeof(name), "supply-%d", i);
+
+		/* Create per-opp directory */
+		d = debugfs_create_dir(name, pdentry);
+
+		if (!d)
+			return false;
+
+		if (!debugfs_create_ulong("u_volt_target", S_IRUGO, d,
+					  &opp->supplies[i].u_volt))
+			return false;
+
+		if (!debugfs_create_ulong("u_volt_min", S_IRUGO, d,
+					  &opp->supplies[i].u_volt_min))
+			return false;
+
+		if (!debugfs_create_ulong("u_volt_max", S_IRUGO, d,
+					  &opp->supplies[i].u_volt_max))
+			return false;
+
+		if (!debugfs_create_ulong("u_amp", S_IRUGO, d,
+					  &opp->supplies[i].u_amp))
+			return false;
+	}
+
+	return true;
+}
+
+int opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table)
+{
+	struct dentry *pdentry = opp_table->dentry;
+	struct dentry *d;
+	char name[25];	/* 20 chars for 64 bit value + 5 (opp:\0) */
+
+	/* Rate is unique to each OPP, use it to give opp-name */
+	snprintf(name, sizeof(name), "opp:%lu", opp->rate);
+
+	/* Create per-opp directory */
+	d = debugfs_create_dir(name, pdentry);
+	if (!d)
+		return -ENOMEM;
+
+	if (!debugfs_create_bool("available", S_IRUGO, d, &opp->available))
+		return -ENOMEM;
+
+	if (!debugfs_create_bool("dynamic", S_IRUGO, d, &opp->dynamic))
+		return -ENOMEM;
+
+	if (!debugfs_create_bool("turbo", S_IRUGO, d, &opp->turbo))
+		return -ENOMEM;
+
+	if (!debugfs_create_bool("suspend", S_IRUGO, d, &opp->suspend))
+		return -ENOMEM;
+
+	if (!debugfs_create_u32("performance_state", S_IRUGO, d, &opp->pstate))
+		return -ENOMEM;
+
+	if (!debugfs_create_ulong("rate_hz", S_IRUGO, d, &opp->rate))
+		return -ENOMEM;
+
+	if (!opp_debug_create_supplies(opp, opp_table, d))
+		return -ENOMEM;
+
+	if (!debugfs_create_ulong("clock_latency_ns", S_IRUGO, d,
+				  &opp->clock_latency_ns))
+		return -ENOMEM;
+
+	opp->dentry = d;
+	return 0;
+}
+
+static int opp_list_debug_create_dir(struct opp_device *opp_dev,
+				     struct opp_table *opp_table)
+{
+	const struct device *dev = opp_dev->dev;
+	struct dentry *d;
+
+	opp_set_dev_name(dev, opp_table->dentry_name);
+
+	/* Create device specific directory */
+	d = debugfs_create_dir(opp_table->dentry_name, rootdir);
+	if (!d) {
+		dev_err(dev, "%s: Failed to create debugfs dir\n", __func__);
+		return -ENOMEM;
+	}
+
+	opp_dev->dentry = d;
+	opp_table->dentry = d;
+
+	return 0;
+}
+
+static int opp_list_debug_create_link(struct opp_device *opp_dev,
+				      struct opp_table *opp_table)
+{
+	const struct device *dev = opp_dev->dev;
+	char name[NAME_MAX];
+	struct dentry *d;
+
+	opp_set_dev_name(opp_dev->dev, name);
+
+	/* Create device specific directory link */
+	d = debugfs_create_symlink(name, rootdir, opp_table->dentry_name);
+	if (!d) {
+		dev_err(dev, "%s: Failed to create link\n", __func__);
+		return -ENOMEM;
+	}
+
+	opp_dev->dentry = d;
+
+	return 0;
+}
+
+/**
+ * opp_debug_register - add a device opp node to the debugfs 'opp' directory
+ * @opp_dev: opp-dev pointer for device
+ * @opp_table: the device-opp being added
+ *
+ * Dynamically adds device specific directory in debugfs 'opp' directory. If the
+ * device-opp is shared with other devices, then links will be created for all
+ * devices except the first.
+ *
+ * Return: 0 on success, otherwise negative error.
+ */
+int opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table)
+{
+	if (!rootdir) {
+		pr_debug("%s: Uninitialized rootdir\n", __func__);
+		return -EINVAL;
+	}
+
+	if (opp_table->dentry)
+		return opp_list_debug_create_link(opp_dev, opp_table);
+
+	return opp_list_debug_create_dir(opp_dev, opp_table);
+}
+
+static void opp_migrate_dentry(struct opp_device *opp_dev,
+			       struct opp_table *opp_table)
+{
+	struct opp_device *new_dev;
+	const struct device *dev;
+	struct dentry *dentry;
+
+	/* Look for next opp-dev */
+	list_for_each_entry(new_dev, &opp_table->dev_list, node)
+		if (new_dev != opp_dev)
+			break;
+
+	/* new_dev is guaranteed to be valid here */
+	dev = new_dev->dev;
+	debugfs_remove_recursive(new_dev->dentry);
+
+	opp_set_dev_name(dev, opp_table->dentry_name);
+
+	dentry = debugfs_rename(rootdir, opp_dev->dentry, rootdir,
+				opp_table->dentry_name);
+	if (!dentry) {
+		dev_err(dev, "%s: Failed to rename link from: %s to %s\n",
+			__func__, dev_name(opp_dev->dev), dev_name(dev));
+		return;
+	}
+
+	new_dev->dentry = dentry;
+	opp_table->dentry = dentry;
+}
+
+/**
+ * opp_debug_unregister - remove a device opp node from debugfs opp directory
+ * @opp_dev: opp-dev pointer for device
+ * @opp_table: the device-opp being removed
+ *
+ * Dynamically removes device specific directory from debugfs 'opp' directory.
+ */
+void opp_debug_unregister(struct opp_device *opp_dev,
+			  struct opp_table *opp_table)
+{
+	if (opp_dev->dentry == opp_table->dentry) {
+		/* Move the real dentry object under another device */
+		if (!list_is_singular(&opp_table->dev_list)) {
+			opp_migrate_dentry(opp_dev, opp_table);
+			goto out;
+		}
+		opp_table->dentry = NULL;
+	}
+
+	debugfs_remove_recursive(opp_dev->dentry);
+
+out:
+	opp_dev->dentry = NULL;
+}
+
+static int __init opp_debug_init(void)
+{
+	/* Create /sys/kernel/debug/opp directory */
+	rootdir = debugfs_create_dir("opp", NULL);
+	if (!rootdir) {
+		pr_err("%s: Failed to create root directory\n", __func__);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+core_initcall(opp_debug_init);