Rafael J. Wysocki | d690b2c | 2010-03-06 21:28:37 +0100 | [diff] [blame] | 1 | /* |
| 2 | * drivers/base/power/generic_ops.c - Generic PM callbacks for subsystems |
| 3 | * |
| 4 | * Copyright (c) 2010 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. |
| 5 | * |
| 6 | * This file is released under the GPLv2. |
| 7 | */ |
| 8 | |
| 9 | #include <linux/pm.h> |
| 10 | #include <linux/pm_runtime.h> |
| 11 | |
| 12 | #ifdef CONFIG_PM_RUNTIME |
| 13 | /** |
| 14 | * pm_generic_runtime_idle - Generic runtime idle callback for subsystems. |
| 15 | * @dev: Device to handle. |
| 16 | * |
| 17 | * If PM operations are defined for the @dev's driver and they include |
| 18 | * ->runtime_idle(), execute it and return its error code, if nonzero. |
| 19 | * Otherwise, execute pm_runtime_suspend() for the device and return 0. |
| 20 | */ |
| 21 | int pm_generic_runtime_idle(struct device *dev) |
| 22 | { |
| 23 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
| 24 | |
| 25 | if (pm && pm->runtime_idle) { |
| 26 | int ret = pm->runtime_idle(dev); |
| 27 | if (ret) |
| 28 | return ret; |
| 29 | } |
| 30 | |
| 31 | pm_runtime_suspend(dev); |
| 32 | return 0; |
| 33 | } |
| 34 | EXPORT_SYMBOL_GPL(pm_generic_runtime_idle); |
| 35 | |
| 36 | /** |
| 37 | * pm_generic_runtime_suspend - Generic runtime suspend callback for subsystems. |
| 38 | * @dev: Device to suspend. |
| 39 | * |
| 40 | * If PM operations are defined for the @dev's driver and they include |
| 41 | * ->runtime_suspend(), execute it and return its error code. Otherwise, |
| 42 | * return -EINVAL. |
| 43 | */ |
| 44 | int pm_generic_runtime_suspend(struct device *dev) |
| 45 | { |
| 46 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
| 47 | int ret; |
| 48 | |
| 49 | ret = pm && pm->runtime_suspend ? pm->runtime_suspend(dev) : -EINVAL; |
| 50 | |
| 51 | return ret; |
| 52 | } |
| 53 | EXPORT_SYMBOL_GPL(pm_generic_runtime_suspend); |
| 54 | |
| 55 | /** |
| 56 | * pm_generic_runtime_resume - Generic runtime resume callback for subsystems. |
| 57 | * @dev: Device to resume. |
| 58 | * |
| 59 | * If PM operations are defined for the @dev's driver and they include |
| 60 | * ->runtime_resume(), execute it and return its error code. Otherwise, |
| 61 | * return -EINVAL. |
| 62 | */ |
| 63 | int pm_generic_runtime_resume(struct device *dev) |
| 64 | { |
| 65 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
| 66 | int ret; |
| 67 | |
| 68 | ret = pm && pm->runtime_resume ? pm->runtime_resume(dev) : -EINVAL; |
| 69 | |
| 70 | return ret; |
| 71 | } |
| 72 | EXPORT_SYMBOL_GPL(pm_generic_runtime_resume); |
| 73 | #endif /* CONFIG_PM_RUNTIME */ |
| 74 | |
| 75 | #ifdef CONFIG_PM_SLEEP |
| 76 | /** |
| 77 | * __pm_generic_call - Generic suspend/freeze/poweroff/thaw subsystem callback. |
| 78 | * @dev: Device to handle. |
| 79 | * @event: PM transition of the system under way. |
| 80 | * |
| 81 | * If the device has not been suspended at run time, execute the |
| 82 | * suspend/freeze/poweroff/thaw callback provided by its driver, if defined, and |
| 83 | * return its error code. Otherwise, return zero. |
| 84 | */ |
| 85 | static int __pm_generic_call(struct device *dev, int event) |
| 86 | { |
| 87 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
| 88 | int (*callback)(struct device *); |
| 89 | |
| 90 | if (!pm || pm_runtime_suspended(dev)) |
| 91 | return 0; |
| 92 | |
| 93 | switch (event) { |
| 94 | case PM_EVENT_SUSPEND: |
| 95 | callback = pm->suspend; |
| 96 | break; |
| 97 | case PM_EVENT_FREEZE: |
| 98 | callback = pm->freeze; |
| 99 | break; |
| 100 | case PM_EVENT_HIBERNATE: |
| 101 | callback = pm->poweroff; |
| 102 | break; |
| 103 | case PM_EVENT_THAW: |
| 104 | callback = pm->thaw; |
| 105 | break; |
| 106 | default: |
| 107 | callback = NULL; |
| 108 | break; |
| 109 | } |
| 110 | |
| 111 | return callback ? callback(dev) : 0; |
| 112 | } |
| 113 | |
| 114 | /** |
| 115 | * pm_generic_suspend - Generic suspend callback for subsystems. |
| 116 | * @dev: Device to suspend. |
| 117 | */ |
| 118 | int pm_generic_suspend(struct device *dev) |
| 119 | { |
| 120 | return __pm_generic_call(dev, PM_EVENT_SUSPEND); |
| 121 | } |
| 122 | EXPORT_SYMBOL_GPL(pm_generic_suspend); |
| 123 | |
| 124 | /** |
| 125 | * pm_generic_freeze - Generic freeze callback for subsystems. |
| 126 | * @dev: Device to freeze. |
| 127 | */ |
| 128 | int pm_generic_freeze(struct device *dev) |
| 129 | { |
| 130 | return __pm_generic_call(dev, PM_EVENT_FREEZE); |
| 131 | } |
| 132 | EXPORT_SYMBOL_GPL(pm_generic_freeze); |
| 133 | |
| 134 | /** |
| 135 | * pm_generic_poweroff - Generic poweroff callback for subsystems. |
| 136 | * @dev: Device to handle. |
| 137 | */ |
| 138 | int pm_generic_poweroff(struct device *dev) |
| 139 | { |
| 140 | return __pm_generic_call(dev, PM_EVENT_HIBERNATE); |
| 141 | } |
| 142 | EXPORT_SYMBOL_GPL(pm_generic_poweroff); |
| 143 | |
| 144 | /** |
| 145 | * pm_generic_thaw - Generic thaw callback for subsystems. |
| 146 | * @dev: Device to thaw. |
| 147 | */ |
| 148 | int pm_generic_thaw(struct device *dev) |
| 149 | { |
| 150 | return __pm_generic_call(dev, PM_EVENT_THAW); |
| 151 | } |
| 152 | EXPORT_SYMBOL_GPL(pm_generic_thaw); |
| 153 | |
| 154 | /** |
| 155 | * __pm_generic_resume - Generic resume/restore callback for subsystems. |
| 156 | * @dev: Device to handle. |
| 157 | * @event: PM transition of the system under way. |
| 158 | * |
| 159 | * Execute the resume/resotre callback provided by the @dev's driver, if |
| 160 | * defined. If it returns 0, change the device's runtime PM status to 'active'. |
| 161 | * Return the callback's error code. |
| 162 | */ |
| 163 | static int __pm_generic_resume(struct device *dev, int event) |
| 164 | { |
| 165 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
| 166 | int (*callback)(struct device *); |
| 167 | int ret; |
| 168 | |
| 169 | if (!pm) |
| 170 | return 0; |
| 171 | |
| 172 | switch (event) { |
| 173 | case PM_EVENT_RESUME: |
| 174 | callback = pm->resume; |
| 175 | break; |
| 176 | case PM_EVENT_RESTORE: |
| 177 | callback = pm->restore; |
| 178 | break; |
| 179 | default: |
| 180 | callback = NULL; |
| 181 | break; |
| 182 | } |
| 183 | |
| 184 | if (!callback) |
| 185 | return 0; |
| 186 | |
| 187 | ret = callback(dev); |
| 188 | if (!ret) { |
| 189 | pm_runtime_disable(dev); |
| 190 | pm_runtime_set_active(dev); |
| 191 | pm_runtime_enable(dev); |
| 192 | } |
| 193 | |
| 194 | return ret; |
| 195 | } |
| 196 | |
| 197 | /** |
| 198 | * pm_generic_resume - Generic resume callback for subsystems. |
| 199 | * @dev: Device to resume. |
| 200 | */ |
| 201 | int pm_generic_resume(struct device *dev) |
| 202 | { |
| 203 | return __pm_generic_resume(dev, PM_EVENT_RESUME); |
| 204 | } |
| 205 | EXPORT_SYMBOL_GPL(pm_generic_resume); |
| 206 | |
| 207 | /** |
| 208 | * pm_generic_restore - Generic restore callback for subsystems. |
| 209 | * @dev: Device to restore. |
| 210 | */ |
| 211 | int pm_generic_restore(struct device *dev) |
| 212 | { |
| 213 | return __pm_generic_resume(dev, PM_EVENT_RESTORE); |
| 214 | } |
| 215 | EXPORT_SYMBOL_GPL(pm_generic_restore); |
| 216 | #endif /* CONFIG_PM_SLEEP */ |
| 217 | |
| 218 | struct dev_pm_ops generic_subsys_pm_ops = { |
| 219 | #ifdef CONFIG_PM_SLEEP |
| 220 | .suspend = pm_generic_suspend, |
| 221 | .resume = pm_generic_resume, |
| 222 | .freeze = pm_generic_freeze, |
| 223 | .thaw = pm_generic_thaw, |
| 224 | .poweroff = pm_generic_poweroff, |
| 225 | .restore = pm_generic_restore, |
| 226 | #endif |
| 227 | #ifdef CONFIG_PM_RUNTIME |
| 228 | .runtime_suspend = pm_generic_runtime_suspend, |
| 229 | .runtime_resume = pm_generic_runtime_resume, |
| 230 | .runtime_idle = pm_generic_runtime_idle, |
| 231 | #endif |
| 232 | }; |
| 233 | EXPORT_SYMBOL_GPL(generic_subsys_pm_ops); |