drm/i915/display: pre-initialize some values in probe_gmdid_display()

When intel_display_device_probe() (and, subsequently,
probe_gmdid_display()) returns, the caller expects ver, rel and step
to be initialized.  Since there's no way to check that there was a
failure and no_display was returned without some further refactoring,
pre-initiliaze all these values to zero to keep it simple and safe.

Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Reviewed-by: Suraj Kandpal <suraj.kandpal@intel.com>
Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230601090338.80284-1-luciano.coelho@intel.com

Author: lucacoelho

drivers/gpu/drm/i915/display/intel_display_device.c

@@ -800,6 +800,15 @@ probe_gmdid_display(struct drm_i915_private *i915, u16 *ver, u16 *rel, u16 *step
 	u32 val;
 	int i;
 
+	/* The caller expects to ver, rel and step to be initialized
+	 * here, and there's no good way to check when there was a
+	 * failure and no_display was returned.  So initialize all these
+	 * values here zero, to be sure.
+	 */
+	*ver = 0;
+	*rel = 0;
+	*step = 0;
+
 	addr = pci_iomap_range(pdev, 0, i915_mmio_reg_offset(GMD_ID_DISPLAY), sizeof(u32));
 	if (!addr) {
 		drm_err(&i915->drm, "Cannot map MMIO BAR to read display GMD_ID\n");