[PATCH] ASoC: cs-amp-lib: Fix NULL pointer crash if efi.get_variable is NULL

[Richard Fitzgerald <rf@xxxxxxxxxxxxxxxxxxxxx>]

Call efi_rt_services_supported() to check that efi.get_variable exists
before calling it.

Signed-off-by: Richard Fitzgerald <rf@xxxxxxxxxxxxxxxxxxxxx>
Fixes: 1cad8725f2b9 ("ASoC: cs-amp-lib: Add helpers for factory calibration data")
---
 sound/soc/codecs/cs-amp-lib.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/soc/codecs/cs-amp-lib.c b/sound/soc/codecs/cs-amp-lib.c
index 287ac01a3873..605964af8afa 100644
--- a/sound/soc/codecs/cs-amp-lib.c
+++ b/sound/soc/codecs/cs-amp-lib.c
@@ -108,7 +108,7 @@ static efi_status_t cs_amp_get_efi_variable(efi_char16_t *name,
 
 	KUNIT_STATIC_STUB_REDIRECT(cs_amp_get_efi_variable, name, guid, size, buf);
 
-	if (IS_ENABLED(CONFIG_EFI))
+	if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE))
 		return efi.get_variable(name, guid, &attr, size, buf);
 
 	return EFI_NOT_FOUND;
-- 
2.39.2