[PATCH 1/7] x86/amd_node: Add a helper for use with `read_poll_timeout`

[Mario Limonciello <superm1@kernel.org>]

From: Mario Limonciello <mario.limonciello@amd.com>

Some of the ACP drivers will poll registers through SMN using
`read_poll_timeout` which requires returning the result of the register
read as the argument.

Add a helper to do just that.

Tested by: Venkata Prasad Potturu <venkataprasad.potturu@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
---
 arch/x86/include/asm/amd_node.h | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/x86/include/asm/amd_node.h b/arch/x86/include/asm/amd_node.h
index 113ad3e8ee40a..9f3f613366f7d 100644
--- a/arch/x86/include/asm/amd_node.h
+++ b/arch/x86/include/asm/amd_node.h
@@ -33,4 +33,15 @@ static inline u16 amd_num_nodes(void)
 int __must_check amd_smn_read(u16 node, u32 address, u32 *value);
 int __must_check amd_smn_write(u16 node, u32 address, u32 value);
 
+/* helper for use with read_poll_timeout */
+static inline int smn_read_register(u32 reg)
+{
+	int data, rc;
+
+	rc = amd_smn_read(0, reg, &data);
+	if (rc)
+		return rc;
+
+	return data;
+}
 #endif /*_ASM_X86_AMD_NODE_H_*/
-- 
2.43.0