[PATCH v2 4/6] bus: mhi: pci_generic: Add support for 64 bit register read & write

Krishna Chaitanya Chundru <[email protected]> Sat, 11 Apr 2026 13:42:04 +0530
Newsgroups dev.linux.lists.mhi,org.kernel.vger.linux-arm-msm,org.kernel.vger.linux-kernel,org.kernel.vger.netdev
Message-ID <[email protected]>
Add functions which does read and write on 64 bit registers.

Signed-off-by: Krishna Chaitanya Chundru <[email protected]>
---
 drivers/bus/mhi/host/pci_generic.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/drivers/bus/mhi/host/pci_generic.c b/drivers/bus/mhi/host/pci_generic.c
index 0884a384b77fc3f56fa62a12351933132ffc9293..b1122c7224bdd469406d96af6d3df342040e1002 100644
--- a/drivers/bus/mhi/host/pci_generic.c
+++ b/drivers/bus/mhi/host/pci_generic.c
@@ -1046,6 +1046,27 @@ struct mhi_pci_device {
 	bool reset_on_remove;
 };
 
+#ifdef readq
+static int mhi_pci_read_reg64(struct mhi_controller *mhi_cntrl,
+			      void __iomem *addr, u64 *out)
+{
+	*out = readq(addr);
+	return 0;
+}
+#else
+#define mhi_pci_read_reg64 NULL
+#endif
+
+#ifdef writeq
+static void mhi_pci_write_reg64(struct mhi_controller *mhi_cntrl,
+				void __iomem *addr, u64 val)
+{
+	writeq(val, addr);
+}
+#else
+#define mhi_pci_write_reg64 NULL
+#endif
+
 static int mhi_pci_read_reg(struct mhi_controller *mhi_cntrl,
 			    void __iomem *addr, u32 *out)
 {
@@ -1347,6 +1368,8 @@ static int mhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 
 	mhi_cntrl->read_reg = mhi_pci_read_reg;
 	mhi_cntrl->write_reg = mhi_pci_write_reg;
+	mhi_cntrl->read_reg64 = mhi_pci_read_reg64;
+	mhi_cntrl->write_reg64 = mhi_pci_write_reg64;
 	mhi_cntrl->status_cb = mhi_pci_status_cb;
 	mhi_cntrl->runtime_get = mhi_pci_runtime_get;
 	mhi_cntrl->runtime_put = mhi_pci_runtime_put;

-- 
2.34.1