[PATCH 1/3] drm/i915/display: Add aux function pointer for fast wake sync pulse count

[Jouni Högander <jouni.hogander@xxxxxxxxx>]

ALPM AUX-Wake fast wake sync pulse count is needed by PSR to calculate IO
wake and fast wake lines.

Signed-off-by: Jouni Högander <jouni.hogander@xxxxxxxxx>
---
 drivers/gpu/drm/i915/display/intel_display_types.h |  6 ++++++
 drivers/gpu/drm/i915/display/intel_dp_aux.c        | 12 +++++++-----
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
index 0d4012097db1..1231d374aeec 100644
--- a/drivers/gpu/drm/i915/display/intel_display_types.h
+++ b/drivers/gpu/drm/i915/display/intel_display_types.h
@@ -1798,6 +1798,12 @@ struct intel_dp {
 	u32 (*get_aux_send_ctl)(struct intel_dp *dp, int send_bytes,
 				u32 aux_clock_divider);
 
+	/*
+	 * This function returns the number of fast wake sync pulses. It is
+	 * needed by PSR code to calculate needed fast wake and io wake lines.
+	 */
+	u8 (*get_aux_fw_sync_len)(void);
+
 	i915_reg_t (*aux_ch_ctl_reg)(struct intel_dp *dp);
 	i915_reg_t (*aux_ch_data_reg)(struct intel_dp *dp, int index);
 
diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux.c b/drivers/gpu/drm/i915/display/intel_dp_aux.c
index 4f4a0e3b3114..fad39b2e3022 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_aux.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_aux.c
@@ -143,10 +143,10 @@ static int intel_dp_aux_sync_len(void)
 	return precharge + preamble;
 }
 
-static int intel_dp_aux_fw_sync_len(void)
+static u8 intel_dp_aux_fw_sync_len(void)
 {
-	int precharge = 10; /* 10-16 */
-	int preamble = 8;
+	u8 precharge = 10; /* 10-16 */
+	u8 preamble = 8;
 
 	return precharge + preamble;
 }
@@ -793,10 +793,12 @@ void intel_dp_aux_init(struct intel_dp *intel_dp)
 	else
 		intel_dp->get_aux_clock_divider = g4x_get_aux_clock_divider;
 
-	if (DISPLAY_VER(i915) >= 9)
+	if (DISPLAY_VER(i915) >= 9) {
 		intel_dp->get_aux_send_ctl = skl_get_aux_send_ctl;
-	else
+		intel_dp->get_aux_fw_sync_len = intel_dp_aux_fw_sync_len;
+	} else {
 		intel_dp->get_aux_send_ctl = g4x_get_aux_send_ctl;
+	}
 
 	intel_dp->aux.drm_dev = &i915->drm;
 	drm_dp_aux_init(&intel_dp->aux);
-- 
2.34.1