2 * PowerNV OPAL Power-Shift-Ratio interface
4 * Copyright 2017 IBM Corp.
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
12 #define pr_fmt(fmt) "opal-psr: " fmt
15 #include <linux/kobject.h>
16 #include <linux/slab.h>
20 DEFINE_MUTEX(psr_mutex);
22 static struct kobject *psr_kobj;
26 struct kobj_attribute attr;
29 static ssize_t psr_show(struct kobject *kobj, struct kobj_attribute *attr,
32 struct psr_attr *psr_attr = container_of(attr, struct psr_attr, attr);
36 token = opal_async_get_token_interruptible();
38 pr_devel("Failed to get token\n");
42 ret = mutex_lock_interruptible(&psr_mutex);
46 ret = opal_get_power_shift_ratio(psr_attr->handle, token,
49 case OPAL_ASYNC_COMPLETION:
50 ret = opal_async_wait_response(token, &msg);
52 pr_devel("Failed to wait for the async response\n");
56 ret = opal_error_code(opal_get_async_rc(msg));
58 ret = sprintf(buf, "%u\n", be32_to_cpu(psr));
64 ret = sprintf(buf, "%u\n", be32_to_cpu(psr));
69 ret = opal_error_code(ret);
73 mutex_unlock(&psr_mutex);
75 opal_async_release_token(token);
79 static ssize_t psr_store(struct kobject *kobj, struct kobj_attribute *attr,
80 const char *buf, size_t count)
82 struct psr_attr *psr_attr = container_of(attr, struct psr_attr, attr);
86 ret = kstrtoint(buf, 0, &psr);
90 token = opal_async_get_token_interruptible();
92 pr_devel("Failed to get token\n");
96 ret = mutex_lock_interruptible(&psr_mutex);
100 ret = opal_set_power_shift_ratio(psr_attr->handle, token, psr);
102 case OPAL_ASYNC_COMPLETION:
103 ret = opal_async_wait_response(token, &msg);
105 pr_devel("Failed to wait for the async response\n");
109 ret = opal_error_code(opal_get_async_rc(msg));
117 ret = opal_error_code(ret);
121 mutex_unlock(&psr_mutex);
123 opal_async_release_token(token);
127 void __init opal_psr_init(void)
129 struct device_node *psr, *node;
132 psr = of_find_compatible_node(NULL, NULL,
133 "ibm,opal-power-shift-ratio");
135 pr_devel("Power-shift-ratio node not found\n");
139 psr_attrs = kcalloc(of_get_child_count(psr), sizeof(*psr_attrs),
144 psr_kobj = kobject_create_and_add("psr", opal_kobj);
146 pr_warn("Failed to create psr kobject\n");
150 for_each_child_of_node(psr, node) {
151 if (of_property_read_u32(node, "handle",
152 &psr_attrs[i].handle))
155 sysfs_attr_init(&psr_attrs[i].attr.attr);
156 if (of_property_read_string(node, "label",
157 &psr_attrs[i].attr.attr.name))
159 psr_attrs[i].attr.attr.mode = 0664;
160 psr_attrs[i].attr.show = psr_show;
161 psr_attrs[i].attr.store = psr_store;
162 if (sysfs_create_file(psr_kobj, &psr_attrs[i].attr.attr)) {
163 pr_devel("Failed to create psr sysfs file %s\n",
164 psr_attrs[i].attr.attr.name);
172 kobject_put(psr_kobj);