14  * If the next upstream device supports PTM, return it; otherwise return
15  * NULL.  PTM Messages are local, so both link partners must support it.
22 	 * Switch Downstream Ports are not permitted to have a PTM  in pci_upstream_ptm()
23 	 * capability; their PTM behavior is controlled by the Upstream  in pci_upstream_ptm()
37  * Find the PTM Capability (if present) and extract the information we need
42 	u16 ptm;  in pci_ptm_init()  local
49 	ptm = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_PTM);  in pci_ptm_init()
50 	if (!ptm)  in pci_ptm_init()
53 	dev->ptm_cap = ptm;  in pci_ptm_init()
56 	pci_read_config_dword(dev, ptm + PCI_PTM_CAP, &cap);  in pci_ptm_init()
61 	 * furthest upstream Time Source as the PTM Root.  For Endpoints,  in pci_ptm_init()
63 	 * reported by the PTM Root and all intervening PTM Time Sources."  in pci_ptm_init()
90 	u16 ptm = dev->ptm_cap;  in pci_save_ptm_state()  local
94 	if (!ptm)  in pci_save_ptm_state()
102 	pci_read_config_dword(dev, ptm + PCI_PTM_CTRL, cap);  in pci_save_ptm_state()
107 	u16 ptm = dev->ptm_cap;  in pci_restore_ptm_state()  local
111 	if (!ptm)  in pci_restore_ptm_state()
119 	pci_write_config_dword(dev, ptm + PCI_PTM_CTRL, *cap);  in pci_restore_ptm_state()
122 /* Enable PTM in the Control register if possible */
125 	u16 ptm = dev->ptm_cap;  in __pci_enable_ptm()  local
129 	if (!ptm)  in __pci_enable_ptm()
133 	 * A device uses local PTM Messages to request time information  in __pci_enable_ptm()
134 	 * from a PTM Root that's farther upstream.  Every device along the  in __pci_enable_ptm()
135 	 * path must support PTM and have it enabled so it can handle the  in __pci_enable_ptm()
136 	 * messages.  Therefore, if this device is not a PTM Root, the  in __pci_enable_ptm()
137 	 * upstream link partner must have PTM enabled before we can enable  in __pci_enable_ptm()
138 	 * PTM.  in __pci_enable_ptm()
146 	pci_read_config_dword(dev, ptm + PCI_PTM_CTRL, &ctrl);  in __pci_enable_ptm()
154 	pci_write_config_dword(dev, ptm + PCI_PTM_CTRL, ctrl);  in __pci_enable_ptm()
166  * Return: zero if successful, or -EINVAL if @dev lacks a PTM Capability or
167  * is not a PTM Root and lacks an upstream path of PTM-enabled devices.
195 	pci_info(dev, "PTM enabled%s, %s granularity\n",  in pci_enable_ptm()
204 	u16 ptm = dev->ptm_cap;  in __pci_disable_ptm()  local
207 	if (!ptm)  in __pci_disable_ptm()
210 	pci_read_config_dword(dev, ptm + PCI_PTM_CTRL, &ctrl);  in __pci_disable_ptm()
212 	pci_write_config_dword(dev, ptm + PCI_PTM_CTRL, ctrl);  in __pci_disable_ptm()
231  * Disable PTM, but preserve dev->ptm_enabled so we silently re-enable it on
240 /* If PTM was enabled before suspend, re-enable it when resuming */