[PATCH v4 2/3] PCI/TPH: expose the enabled TPH requester type

[Zhiping Zhang <zhipingz@meta.com>]

Add pcie_tph_enabled_req_type() so drivers can query the enabled TPH
requester mode without reaching into pci_dev internals. A
!CONFIG_PCIE_TPH stub returns PCI_TPH_REQ_DISABLE so callers need no
ifdef.

Signed-off-by: Zhiping Zhang <zhipingz@meta.com>
---
 drivers/pci/tph.c       | 12 ++++++++++++
 include/linux/pci-tph.h |  2 ++
 2 files changed, 14 insertions(+)

diff --git a/drivers/pci/tph.c b/drivers/pci/tph.c
index 91145e8d9d95..6c4492075ae9 100644
--- a/drivers/pci/tph.c
+++ b/drivers/pci/tph.c
@@ -174,6 +174,18 @@ u32 pcie_tph_get_st_table_loc(struct pci_dev *pdev)
 }
 EXPORT_SYMBOL(pcie_tph_get_st_table_loc);
 
+/**
+ * pcie_tph_enabled_req_type - Return the device's enabled TPH requester type
+ * @pdev: PCI device to query
+ *
+ * Return: PCI_TPH_REQ_DISABLE, PCI_TPH_REQ_TPH_ONLY or PCI_TPH_REQ_EXT_TPH.
+ */
+u8 pcie_tph_enabled_req_type(struct pci_dev *pdev)
+{
+	return pdev->tph_req_type;
+}
+EXPORT_SYMBOL(pcie_tph_enabled_req_type);
+
 /*
  * Return the size of ST table. If ST table is not in TPH Requester Extended
  * Capability space, return 0. Otherwise return the ST Table Size + 1.
diff --git a/include/linux/pci-tph.h b/include/linux/pci-tph.h
index be68cd17f2f8..fe572737b409 100644
--- a/include/linux/pci-tph.h
+++ b/include/linux/pci-tph.h
@@ -30,6 +30,7 @@ void pcie_disable_tph(struct pci_dev *pdev);
 int pcie_enable_tph(struct pci_dev *pdev, int mode);
 u16 pcie_tph_get_st_table_size(struct pci_dev *pdev);
 u32 pcie_tph_get_st_table_loc(struct pci_dev *pdev);
+u8 pcie_tph_enabled_req_type(struct pci_dev *pdev);
 #else
 static inline int pcie_tph_set_st_entry(struct pci_dev *pdev,
 					unsigned int index, u16 tag)
@@ -41,6 +42,7 @@ static inline int pcie_tph_get_cpu_st(struct pci_dev *dev,
 static inline void pcie_disable_tph(struct pci_dev *pdev) { }
 static inline int pcie_enable_tph(struct pci_dev *pdev, int mode)
 { return -EINVAL; }
+static inline u8 pcie_tph_enabled_req_type(struct pci_dev *pdev) { return 0; }
 #endif
 
 #endif /* LINUX_PCI_TPH_H */
-- 
2.53.0-Meta