diff options
Diffstat (limited to 'drivers/base/power/opp/debugfs.c')
| -rw-r--r-- | drivers/base/power/opp/debugfs.c | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/drivers/base/power/opp/debugfs.c b/drivers/base/power/opp/debugfs.c new file mode 100644 index 000000000..ddfe4773e --- /dev/null +++ b/drivers/base/power/opp/debugfs.c @@ -0,0 +1,219 @@ +/* + * 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 device_opp *dev_opp) +{ + struct dentry *pdentry = dev_opp->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 device_opp_debug_create_dir(struct device_list_opp *list_dev, + struct device_opp *dev_opp) +{ + const struct device *dev = list_dev->dev; + struct dentry *d; + + opp_set_dev_name(dev, dev_opp->dentry_name); + + /* Create device specific directory */ + d = debugfs_create_dir(dev_opp->dentry_name, rootdir); + if (!d) { + dev_err(dev, "%s: Failed to create debugfs dir\n", __func__); + return -ENOMEM; + } + + list_dev->dentry = d; + dev_opp->dentry = d; + + return 0; +} + +static int device_opp_debug_create_link(struct device_list_opp *list_dev, + struct device_opp *dev_opp) +{ + const struct device *dev = list_dev->dev; + char name[NAME_MAX]; + struct dentry *d; + + opp_set_dev_name(list_dev->dev, name); + + /* Create device specific directory link */ + d = debugfs_create_symlink(name, rootdir, dev_opp->dentry_name); + if (!d) { + dev_err(dev, "%s: Failed to create link\n", __func__); + return -ENOMEM; + } + + list_dev->dentry = d; + + return 0; +} + +/** + * opp_debug_register - add a device opp node to the debugfs 'opp' directory + * @list_dev: list-dev pointer for device + * @dev_opp: 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 device_list_opp *list_dev, + struct device_opp *dev_opp) +{ + if (!rootdir) { + pr_debug("%s: Uninitialized rootdir\n", __func__); + return -EINVAL; + } + + if (dev_opp->dentry) + return device_opp_debug_create_link(list_dev, dev_opp); + + return device_opp_debug_create_dir(list_dev, dev_opp); +} + +static void opp_migrate_dentry(struct device_list_opp *list_dev, + struct device_opp *dev_opp) +{ + struct device_list_opp *new_dev; + const struct device *dev; + struct dentry *dentry; + + /* Look for next list-dev */ + list_for_each_entry(new_dev, &dev_opp->dev_list, node) + if (new_dev != list_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, dev_opp->dentry_name); + + dentry = debugfs_rename(rootdir, list_dev->dentry, rootdir, + dev_opp->dentry_name); + if (!dentry) { + dev_err(dev, "%s: Failed to rename link from: %s to %s\n", + __func__, dev_name(list_dev->dev), dev_name(dev)); + return; + } + + new_dev->dentry = dentry; + dev_opp->dentry = dentry; +} + +/** + * opp_debug_unregister - remove a device opp node from debugfs opp directory + * @list_dev: list-dev pointer for device + * @dev_opp: the device-opp being removed + * + * Dynamically removes device specific directory from debugfs 'opp' directory. + */ +void opp_debug_unregister(struct device_list_opp *list_dev, + struct device_opp *dev_opp) +{ + if (list_dev->dentry == dev_opp->dentry) { + /* Move the real dentry object under another device */ + if (!list_is_singular(&dev_opp->dev_list)) { + opp_migrate_dentry(list_dev, dev_opp); + goto out; + } + dev_opp->dentry = NULL; + } + + debugfs_remove_recursive(list_dev->dentry); + +out: + list_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); |