[PATCH] soc: qcom: smem: Add stubs for CONFIG_QCOM_SMEM=n

From: Daniel Baluta

Date: Tue Aug 11 2026 - 08:32:55 EST


drivers/soc/qcom/ubwc_config.c calls qcom_smem_is_available() and
qcom_smem_dram_get_hbb() unconditionally. These symbols are provided
by the QCOM_SMEM module, but QCOM_UBWC_CONFIG can be selected by
DRM_MSM even on non-Qcom platforms (e.g. with SOC_IMX5) thus resulting
in the following link error:

arm-linux-gnueabihf-ld: ubwc_config.c:(.text+0x2c): undefined
reference to 'qcom_smem_is_available'
arm-linux-gnueabihf-ld: ubwc_config.c:(.text+0x4c): undefined
reference to 'qcom_smem_dram_get_hbb'

Add static inline stub definitions for the !CONFIG_QCOM_SMEM case for
all `qcom_smem_` functions in order to fix the issue above.

Fixes: 1b445022d1d0 ("soc: qcom: ubwc: Get HBB from SMEM")
Signed-off-by: Daniel Baluta <daniel.baluta@xxxxxxx>
---
include/linux/soc/qcom/smem.h | 51 +++++++++++++++++++++++++++++++++++
1 file changed, 51 insertions(+)

diff --git a/include/linux/soc/qcom/smem.h b/include/linux/soc/qcom/smem.h
index 3249cbd2016b5..d35ab5d248054 100644
--- a/include/linux/soc/qcom/smem.h
+++ b/include/linux/soc/qcom/smem.h
@@ -4,6 +4,8 @@

#define QCOM_SMEM_HOST_ANY -1

+#if IS_ENABLED(CONFIG_QCOM_SMEM)
+
bool qcom_smem_is_available(void);
int qcom_smem_alloc(unsigned host, unsigned item, size_t size);
void *qcom_smem_get(unsigned host, unsigned item, size_t *size);
@@ -19,4 +21,53 @@ int qcom_smem_bust_hwspin_lock_by_host(unsigned int host);

int qcom_smem_dram_get_hbb(void);

+#else
+
+static inline bool qcom_smem_is_available(void)
+{
+ return false;
+}
+
+static inline int qcom_smem_alloc(unsigned int host, unsigned int item, size_t size)
+{
+ return -ENODEV;
+}
+
+static inline void *qcom_smem_get(unsigned int host, unsigned int item, size_t *size)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline int qcom_smem_get_free_space(unsigned int host)
+{
+ return -ENODEV;
+}
+
+static inline phys_addr_t qcom_smem_virt_to_phys(void *p)
+{
+ return 0;
+}
+
+static inline int qcom_smem_get_soc_id(u32 *id)
+{
+ return -ENODEV;
+}
+
+static inline int qcom_smem_get_feature_code(u32 *code)
+{
+ return -ENODEV;
+}
+
+static inline int qcom_smem_bust_hwspin_lock_by_host(unsigned int host)
+{
+ return -ENODEV;
+}
+
+static inline int qcom_smem_dram_get_hbb(void)
+{
+ return -ENODATA;
+}
+
+#endif /* CONFIG_QCOM_SMEM */
+
#endif
--
2.45.2