diff options
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/power/pci.txt | 35 |
1 files changed, 2 insertions, 33 deletions
diff --git a/Documentation/power/pci.txt b/Documentation/power/pci.txt index c85428e7ad92..35b1a7dae342 100644 --- a/Documentation/power/pci.txt +++ b/Documentation/power/pci.txt | |||
@@ -165,40 +165,9 @@ Description: | |||
165 | These functions are intended for use by individual drivers, and are defined in | 165 | These functions are intended for use by individual drivers, and are defined in |
166 | struct pci_driver: | 166 | struct pci_driver: |
167 | 167 | ||
168 | int (*save_state) (struct pci_dev *dev, u32 state); | 168 | int (*suspend) (struct pci_dev *dev, pm_message_t state); |
169 | int (*suspend) (struct pci_dev *dev, u32 state); | ||
170 | int (*resume) (struct pci_dev *dev); | 169 | int (*resume) (struct pci_dev *dev); |
171 | int (*enable_wake) (struct pci_dev *dev, u32 state, int enable); | 170 | int (*enable_wake) (struct pci_dev *dev, pci_power_t state, int enable); |
172 | |||
173 | |||
174 | save_state | ||
175 | ---------- | ||
176 | |||
177 | Usage: | ||
178 | |||
179 | if (dev->driver && dev->driver->save_state) | ||
180 | dev->driver->save_state(dev,state); | ||
181 | |||
182 | The driver should use this callback to save device state. It should take into | ||
183 | account the current state of the device and the requested state in order to | ||
184 | avoid any unnecessary operations. | ||
185 | |||
186 | For example, a video card that supports all 4 states (D0-D3), all controller | ||
187 | context is preserved when entering D1, but the screen is placed into a low power | ||
188 | state (blanked). | ||
189 | |||
190 | The driver can also interpret this function as a notification that it may be | ||
191 | entering a sleep state in the near future. If it knows that the device cannot | ||
192 | enter the requested state, either because of lack of support for it, or because | ||
193 | the device is middle of some critical operation, then it should fail. | ||
194 | |||
195 | This function should not be used to set any state in the device or the driver | ||
196 | because the device may not actually enter the sleep state (e.g. another driver | ||
197 | later causes causes a global state transition to fail). | ||
198 | |||
199 | Note that in intermediate low power states, a device's I/O and memory spaces may | ||
200 | be disabled and may not be available in subsequent transitions to lower power | ||
201 | states. | ||
202 | 171 | ||
203 | 172 | ||
204 | suspend | 173 | suspend |