Commit 52ade9b3b97fd3bea42842a056fe0786c28d0555 changed the suspend code ordering to execute pm_ops->prepare() after the device model per-device .suspend() calls in order to fix some ACPI-related issues. Unfortunately, it broke the at91 platform which assumed that pm_ops->prepare() would be called before suspending devices. at91 used pm_ops->prepare() to get notified of the target system sleep state, so that it could use this information while suspending devices. However, with the current suspend code ordering pm_ops->prepare() is called too late for this purpose. Thus, at91 needs an additional method in 'struct pm_ops' that will be used for notifying the platform of the target system sleep state. Moreover, in the future such a method will also be needed by ACPI. This patch adds the .set_target() method to 'struct pm_ops' and makes the suspend code call it, if implemented, before executing the device model per-device .suspend() calls. It also modifies the at91 code to use pm_ops->set_target() instead of pm_ops->prepare().
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| @@ -110,37 +110,67 @@ typedef int __bitwise suspend_state_t; · 109 unmodified lines | |||
| 110 | #define PM_SUSPEND_MAX ((__force suspend_state_t) 4) | 110 | #define PM_SUSPEND_MAX ((__force suspend_state_t) 4) |
| 111 | 111 | ||
| 112 | /** | 112 | /** |
| 113 | * struct pm_ops - Callbacks for managing platform dependent suspend states. | 113 | * struct pm_ops - Callbacks for managing platform dependent system sleep |
| 114 | * @valid: Callback to determine whether the given state can be entered. | 114 | * states. |
| 115 | * Valid states are advertised in /sys/power/state but can still | ||
| 116 | * be rejected by prepare or enter if the conditions aren't right. | ||
| 117 | * There is a %pm_valid_only_mem function available that can be assigned | ||
| 118 | * to this if you only implement mem sleep. | ||
| 119 | * | 115 | * |
| 120 | * @prepare: Prepare the platform for the given suspend state. Can return a | 116 | * @valid: Callback to determine if given system sleep state is supported by |
| 121 | * negative error code if necessary. | 117 | * the platform. |
| 118 | * Valid (ie. supported) states are advertised in /sys/power/state. Note | ||
| 119 | * that it still may be impossible to enter given system sleep state if the | ||
| 120 | * conditions aren't right. | ||
| 121 | * There is the %pm_valid_only_mem function available that can be assigned | ||
| 122 | * to this if the platform only supports mem sleep. | ||
| 122 | * | 123 | * |
| 123 | * @enter: Enter the given suspend state, must be assigned. Can return a | 124 | * @set_target: Tell the platform which system sleep state is going to be |
| 124 | * negative error code if necessary. | 125 | * entered. |
| 126 | * @set_target() is executed right prior to suspending devices. The | ||
| 127 | * information conveyed to the platform code by @set_target() should be | ||
| 128 | * disregarded by the platform as soon as @finish() is executed and if | ||
| 129 | * @prepare() fails. If @set_target() fails (ie. returns nonzero), | ||
| 130 | * @prepare(), @enter() and @finish() will not be called by the PM core. | ||
| 131 | * This callback is optional. However, if it is implemented, the argument | ||
| 132 | * passed to @prepare(), @enter() and @finish() is meaningless and should | ||
| 133 | * be ignored. | ||
| 125 | * | 134 | * |
| 126 | * @finish: Called when the system has left the given state and all devices | 135 | * @prepare: Prepare the platform for entering the system sleep state indicated |
| 127 | * are resumed. The return value is ignored. | 136 | * by @set_target() or represented by the argument if @set_target() is not |
| 137 | * implemented. | ||
| 138 | * @prepare() is called right after devices have been suspended (ie. the | ||
| 139 | * appropriate .suspend() method has been executed for each device) and | ||
| 140 | * before the nonboot CPUs are disabled (it is executed with IRQs enabled). | ||
| 141 | * This callback is optional. It returns 0 on success or a negative | ||
| 142 | * error code otherwise, in which case the system cannot enter the desired | ||
| 143 | * sleep state (@enter() and @finish() will not be called in that case). | ||
| 144 | * | ||
| 145 | * @enter: Enter the system sleep state indicated by @set_target() or | ||
| 146 | * represented by the argument if @set_target() is not implemented. | ||
| 147 | * This callback is mandatory. It returns 0 on success or a negative | ||
| 148 | * error code otherwise, in which case the system cannot enter the desired | ||
| 149 | * sleep state. | ||
| 150 | * | ||
| 151 | * @finish: Called when the system has just left a sleep state, right after | ||
| 152 | * the nonboot CPUs have been enabled and before devices are resumed (it is | ||
| 153 | * executed with IRQs enabled). If @set_target() is not implemented, the | ||
| 154 | * argument represents the sleep state being left. | ||
| 155 | * This callback is optional, but should be implemented by the platforms | ||
| 156 | * that implement @prepare(). If implemented, it is always called after | ||
| 157 | * @enter() (even if @enter() fails). | ||
| 128 | */ | 158 | */ |
| 129 | struct pm_ops { | 159 | struct pm_ops { |
| 130 | int (*valid)(suspend_state_t state); | 160 | int (*valid)(suspend_state_t state); |
| 161 | int (*set_target)(suspend_state_t state); | ||
| 131 | int (*prepare)(suspend_state_t state); | 162 | int (*prepare)(suspend_state_t state); |
| 132 | int (*enter)(suspend_state_t state); | 163 | int (*enter)(suspend_state_t state); |
| 133 | int (*finish)(suspend_state_t state); | 164 | int (*finish)(suspend_state_t state); |
| 134 | }; | 165 | }; |
| 135 | 166 | ||
| 167 | extern struct pm_ops *pm_ops; | ||
| 168 | |||
| 136 | /** | 169 | /** |
| 137 | * pm_set_ops - set platform dependent power management ops | 170 | * pm_set_ops - set platform dependent power management ops |
| 138 | * @pm_ops: The new power management operations to set. | 171 | * @pm_ops: The new power management operations to set. |
| 139 | */ | 172 | */ |
| 140 | extern void pm_set_ops(struct pm_ops *pm_ops); | 173 | extern void pm_set_ops(struct pm_ops *pm_ops); |
| 141 | extern struct pm_ops *pm_ops; | ||
| 142 | extern int pm_suspend(suspend_state_t state); | ||
| 143 | |||
| 144 | extern int pm_valid_only_mem(suspend_state_t state); | 174 | extern int pm_valid_only_mem(suspend_state_t state); |
| 145 | 175 | ||
| 146 | /** | 176 | /** |
| @@ -161,6 +191,8 @@ extern void arch_suspend_disable_irqs(void); · 14 unmodified lines | |||
| 161 | */ | 191 | */ |
| 162 | extern void arch_suspend_enable_irqs(void); | 192 | extern void arch_suspend_enable_irqs(void); |
| 163 | 193 | ||
| 194 | extern int pm_suspend(suspend_state_t state); | ||
| 195 | |||
| 164 | /* | 196 | /* |
| 165 | * Device power management | 197 | * Device power management |
| 166 | */ | 198 | */ |