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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 | // SPDX-License-Identifier: GPL-2.0-or-later /* * PowerNV OPAL Power-Shift-Ratio interface * * Copyright 2017 IBM Corp. */ #define pr_fmt(fmt) "opal-psr: " fmt #include <linux/of.h> #include <linux/kobject.h> #include <linux/slab.h> #include <asm/opal.h> static DEFINE_MUTEX(psr_mutex); static struct kobject *psr_kobj; static struct psr_attr { u32 handle; struct kobj_attribute attr; } *psr_attrs; static ssize_t psr_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { struct psr_attr *psr_attr = container_of(attr, struct psr_attr, attr); struct opal_msg msg; int psr, ret, token; token = opal_async_get_token_interruptible(); if (token < 0) { pr_devel("Failed to get token\n"); return token; } ret = mutex_lock_interruptible(&psr_mutex); if (ret) goto out_token; ret = opal_get_power_shift_ratio(psr_attr->handle, token, (u32 *)__pa(&psr)); switch (ret) { case OPAL_ASYNC_COMPLETION: ret = opal_async_wait_response(token, &msg); if (ret) { pr_devel("Failed to wait for the async response\n"); ret = -EIO; goto out; } ret = opal_error_code(opal_get_async_rc(msg)); if (!ret) { ret = sprintf(buf, "%u\n", be32_to_cpu(psr)); if (ret < 0) ret = -EIO; } break; case OPAL_SUCCESS: ret = sprintf(buf, "%u\n", be32_to_cpu(psr)); if (ret < 0) ret = -EIO; break; default: ret = opal_error_code(ret); } out: mutex_unlock(&psr_mutex); out_token: opal_async_release_token(token); return ret; } static ssize_t psr_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { struct psr_attr *psr_attr = container_of(attr, struct psr_attr, attr); struct opal_msg msg; int psr, ret, token; ret = kstrtoint(buf, 0, &psr); if (ret) return ret; token = opal_async_get_token_interruptible(); if (token < 0) { pr_devel("Failed to get token\n"); return token; } ret = mutex_lock_interruptible(&psr_mutex); if (ret) goto out_token; ret = opal_set_power_shift_ratio(psr_attr->handle, token, psr); switch (ret) { case OPAL_ASYNC_COMPLETION: ret = opal_async_wait_response(token, &msg); if (ret) { pr_devel("Failed to wait for the async response\n"); ret = -EIO; goto out; } ret = opal_error_code(opal_get_async_rc(msg)); if (!ret) ret = count; break; case OPAL_SUCCESS: ret = count; break; default: ret = opal_error_code(ret); } out: mutex_unlock(&psr_mutex); out_token: opal_async_release_token(token); return ret; } void __init opal_psr_init(void) { struct device_node *psr, *node; int i = 0; psr = of_find_compatible_node(NULL, NULL, "ibm,opal-power-shift-ratio"); if (!psr) { pr_devel("Power-shift-ratio node not found\n"); return; } psr_attrs = kcalloc(of_get_child_count(psr), sizeof(*psr_attrs), GFP_KERNEL); if (!psr_attrs) goto out_put_psr; psr_kobj = kobject_create_and_add("psr", opal_kobj); if (!psr_kobj) { pr_warn("Failed to create psr kobject\n"); goto out; } for_each_child_of_node(psr, node) { if (of_property_read_u32(node, "handle", &psr_attrs[i].handle)) goto out_kobj; sysfs_attr_init(&psr_attrs[i].attr.attr); if (of_property_read_string(node, "label", &psr_attrs[i].attr.attr.name)) goto out_kobj; psr_attrs[i].attr.attr.mode = 0664; psr_attrs[i].attr.show = psr_show; psr_attrs[i].attr.store = psr_store; if (sysfs_create_file(psr_kobj, &psr_attrs[i].attr.attr)) { pr_devel("Failed to create psr sysfs file %s\n", psr_attrs[i].attr.attr.name); goto out_kobj; } i++; } of_node_put(psr); return; out_kobj: of_node_put(node); kobject_put(psr_kobj); out: kfree(psr_attrs); out_put_psr: of_node_put(psr); } |