[deliverable/linux.git] / drivers / base / power / opp / debugfs.c

/*
 * 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 "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);
}

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_ulong("rate_hz", S_IRUGO, d, &opp->rate))
		return -ENOMEM;

	if (!debugfs_create_ulong("u_volt_target", S_IRUGO, d, &opp->u_volt))
		return -ENOMEM;

	if (!debugfs_create_ulong("u_volt_min", S_IRUGO, d, &opp->u_volt_min))
		return -ENOMEM;

	if (!debugfs_create_ulong("u_volt_max", S_IRUGO, d, &opp->u_volt_max))
		return -ENOMEM;

	if (!debugfs_create_ulong("u_amp", S_IRUGO, d, &opp->u_amp))
		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);
Commit	Line	Data
deaa5146 VK	1	/*
	2	* Generic OPP debugfs interface
	3	*
	4	* Copyright (C) 2015-2016 Viresh Kumar <viresh.kumar@linaro.org>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License version 2 as
	8	* published by the Free Software Foundation.
	9	*/
	10
	11	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	12
	13	#include <linux/debugfs.h>
	14	#include <linux/device.h>
	15	#include <linux/err.h>
	16	#include <linux/init.h>
	17	#include <linux/limits.h>
	18
	19	#include "opp.h"
	20
	21	static struct dentry *rootdir;
	22
	23	static void opp_set_dev_name(const struct device dev, char name)
	24	{
	25	if (dev->parent)
	26	snprintf(name, NAME_MAX, "%s-%s", dev_name(dev->parent),
	27	dev_name(dev));
	28	else
	29	snprintf(name, NAME_MAX, "%s", dev_name(dev));
	30	}
	31
	32	void opp_debug_remove_one(struct dev_pm_opp *opp)
	33	{
	34	debugfs_remove_recursive(opp->dentry);
	35	}
	36
2c2709dc	37	int opp_debug_create_one(struct dev_pm_opp opp, struct opp_table opp_table)
deaa5146	38	{
2c2709dc	39	struct dentry *pdentry = opp_table->dentry;
deaa5146 VK	40	struct dentry *d;
	41	char name[25]; /* 20 chars for 64 bit value + 5 (opp:\0) */
	42
	43	/* Rate is unique to each OPP, use it to give opp-name */
	44	snprintf(name, sizeof(name), "opp:%lu", opp->rate);
	45
	46	/* Create per-opp directory */
	47	d = debugfs_create_dir(name, pdentry);
	48	if (!d)
	49	return -ENOMEM;
	50
	51	if (!debugfs_create_bool("available", S_IRUGO, d, &opp->available))
	52	return -ENOMEM;
	53
	54	if (!debugfs_create_bool("dynamic", S_IRUGO, d, &opp->dynamic))
	55	return -ENOMEM;
	56
	57	if (!debugfs_create_bool("turbo", S_IRUGO, d, &opp->turbo))
	58	return -ENOMEM;
	59
	60	if (!debugfs_create_bool("suspend", S_IRUGO, d, &opp->suspend))
	61	return -ENOMEM;
	62
	63	if (!debugfs_create_ulong("rate_hz", S_IRUGO, d, &opp->rate))
	64	return -ENOMEM;
	65
	66	if (!debugfs_create_ulong("u_volt_target", S_IRUGO, d, &opp->u_volt))
	67	return -ENOMEM;
	68
	69	if (!debugfs_create_ulong("u_volt_min", S_IRUGO, d, &opp->u_volt_min))
	70	return -ENOMEM;
	71
	72	if (!debugfs_create_ulong("u_volt_max", S_IRUGO, d, &opp->u_volt_max))
	73	return -ENOMEM;
	74
	75	if (!debugfs_create_ulong("u_amp", S_IRUGO, d, &opp->u_amp))
	76	return -ENOMEM;
	77
	78	if (!debugfs_create_ulong("clock_latency_ns", S_IRUGO, d,
	79	&opp->clock_latency_ns))
	80	return -ENOMEM;
	81
	82	opp->dentry = d;
	83	return 0;
	84	}
	85
2c2709dc VK	86	static int opp_list_debug_create_dir(struct opp_device *opp_dev,
2c2709dc VK	87	struct opp_table *opp_table)
deaa5146	88	{
2c2709dc	89	const struct device *dev = opp_dev->dev;
deaa5146 VK	90	struct dentry *d;
deaa5146 VK	91
2c2709dc	92	opp_set_dev_name(dev, opp_table->dentry_name);
deaa5146 VK	93
deaa5146 VK	94	/* Create device specific directory */
2c2709dc	95	d = debugfs_create_dir(opp_table->dentry_name, rootdir);
deaa5146 VK	96	if (!d) {
	97	dev_err(dev, "%s: Failed to create debugfs dir\n", __func__);
	98	return -ENOMEM;
	99	}
	100
2c2709dc VK	101	opp_dev->dentry = d;
2c2709dc VK	102	opp_table->dentry = d;
deaa5146 VK	103
	104	return 0;
	105	}
	106
2c2709dc VK	107	static int opp_list_debug_create_link(struct opp_device *opp_dev,
2c2709dc VK	108	struct opp_table *opp_table)
deaa5146	109	{
2c2709dc	110	const struct device *dev = opp_dev->dev;
deaa5146 VK	111	char name[NAME_MAX];
	112	struct dentry *d;
	113
2c2709dc	114	opp_set_dev_name(opp_dev->dev, name);
deaa5146 VK	115
deaa5146 VK	116	/* Create device specific directory link */
2c2709dc	117	d = debugfs_create_symlink(name, rootdir, opp_table->dentry_name);
deaa5146 VK	118	if (!d) {
	119	dev_err(dev, "%s: Failed to create link\n", __func__);
	120	return -ENOMEM;
	121	}
	122
2c2709dc	123	opp_dev->dentry = d;
deaa5146 VK	124
	125	return 0;
	126	}
	127
	128	/**
	129	* opp_debug_register - add a device opp node to the debugfs 'opp' directory
2c2709dc VK	130	* @opp_dev: opp-dev pointer for device
2c2709dc VK	131	* @opp_table: the device-opp being added
deaa5146 VK	132	*
	133	* Dynamically adds device specific directory in debugfs 'opp' directory. If the
	134	* device-opp is shared with other devices, then links will be created for all
	135	* devices except the first.
	136	*
	137	* Return: 0 on success, otherwise negative error.
	138	*/
2c2709dc	139	int opp_debug_register(struct opp_device opp_dev, struct opp_table opp_table)
deaa5146 VK	140	{
	141	if (!rootdir) {
	142	pr_debug("%s: Uninitialized rootdir\n", __func__);
	143	return -EINVAL;
	144	}
	145
2c2709dc VK	146	if (opp_table->dentry)
2c2709dc VK	147	return opp_list_debug_create_link(opp_dev, opp_table);
deaa5146	148
2c2709dc	149	return opp_list_debug_create_dir(opp_dev, opp_table);
deaa5146 VK	150	}
deaa5146 VK	151
2c2709dc VK	152	static void opp_migrate_dentry(struct opp_device *opp_dev,
2c2709dc VK	153	struct opp_table *opp_table)
deaa5146	154	{
2c2709dc	155	struct opp_device *new_dev;
deaa5146 VK	156	const struct device *dev;
	157	struct dentry *dentry;
	158
2c2709dc VK	159	/* Look for next opp-dev */
	160	list_for_each_entry(new_dev, &opp_table->dev_list, node)
	161	if (new_dev != opp_dev)
deaa5146 VK	162	break;
	163
	164	/* new_dev is guaranteed to be valid here */
	165	dev = new_dev->dev;
	166	debugfs_remove_recursive(new_dev->dentry);
	167
2c2709dc	168	opp_set_dev_name(dev, opp_table->dentry_name);
deaa5146	169
2c2709dc VK	170	dentry = debugfs_rename(rootdir, opp_dev->dentry, rootdir,
2c2709dc VK	171	opp_table->dentry_name);
deaa5146 VK	172	if (!dentry) {
deaa5146 VK	173	dev_err(dev, "%s: Failed to rename link from: %s to %s\n",
2c2709dc	174	__func__, dev_name(opp_dev->dev), dev_name(dev));
deaa5146 VK	175	return;
	176	}
	177
	178	new_dev->dentry = dentry;
2c2709dc	179	opp_table->dentry = dentry;
deaa5146 VK	180	}
	181
	182	/**
	183	* opp_debug_unregister - remove a device opp node from debugfs opp directory
2c2709dc VK	184	* @opp_dev: opp-dev pointer for device
2c2709dc VK	185	* @opp_table: the device-opp being removed
deaa5146 VK	186	*
	187	* Dynamically removes device specific directory from debugfs 'opp' directory.
	188	*/
2c2709dc VK	189	void opp_debug_unregister(struct opp_device *opp_dev,
2c2709dc VK	190	struct opp_table *opp_table)
deaa5146	191	{
2c2709dc	192	if (opp_dev->dentry == opp_table->dentry) {
deaa5146	193	/* Move the real dentry object under another device */
2c2709dc VK	194	if (!list_is_singular(&opp_table->dev_list)) {
2c2709dc VK	195	opp_migrate_dentry(opp_dev, opp_table);
deaa5146 VK	196	goto out;
deaa5146 VK	197	}
2c2709dc	198	opp_table->dentry = NULL;
deaa5146 VK	199	}
deaa5146 VK	200
2c2709dc	201	debugfs_remove_recursive(opp_dev->dentry);
deaa5146 VK	202
deaa5146 VK	203	out:
2c2709dc	204	opp_dev->dentry = NULL;
deaa5146 VK	205	}
	206
	207	static int __init opp_debug_init(void)
	208	{
	209	/* Create /sys/kernel/debug/opp directory */
	210	rootdir = debugfs_create_dir("opp", NULL);
	211	if (!rootdir) {
	212	pr_err("%s: Failed to create root directory\n", __func__);
	213	return -ENOMEM;
	214	}
	215
	216	return 0;
	217	}
	218	core_initcall(opp_debug_init);