[PATCH 09/18] drm/i915/power-well: use generic read_poll_timeout() instead of wait_for() for DKL PHY

[Jani Nikula]

Prefer generic poll helpers over i915 custom helpers.

The functional change is losing the exponentially growing sleep of
wait_for(), which used to be 10, 20, 40, ..., 640, and 1280 us.

Use an arbitrary constant 100 us sleep instead. The timeout remains at 1
ms.

Signed-off-by: Jani Nikula <jani.nikula at intel.com>
---
 .../drm/i915/display/intel_display_power_well.c    | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display_power_well.c b/drivers/gpu/drm/i915/display/intel_display_power_well.c
index 4a876fa815bd..92f4c81d9d1f 100644
--- a/drivers/gpu/drm/i915/display/intel_display_power_well.c
+++ b/drivers/gpu/drm/i915/display/intel_display_power_well.c
@@ -3,6 +3,8 @@
  * Copyright © 2022 Intel Corporation
  */
 
+#include <linux/iopoll.h>
+
 #include "i915_drv.h"
 #include "i915_irq.h"
 #include "i915_reg.h"
@@ -521,6 +523,8 @@ icl_tc_phy_aux_power_well_enable(struct intel_display *display,
 	const struct i915_power_well_regs *regs = power_well->desc->ops->regs;
 	bool is_tbt = power_well->desc->is_tc_tbt;
 	bool timeout_expected;
+	u32 val;
+	int ret;
 
 	icl_tc_port_assert_ref_held(display, power_well, dig_port);
 
@@ -547,10 +551,12 @@ icl_tc_phy_aux_power_well_enable(struct intel_display *display,
 
 		tc_port = TGL_AUX_PW_TO_TC_PORT(i915_power_well_instance(power_well)->hsw.idx);
 
-		if (wait_for(intel_dkl_phy_read(display, DKL_CMN_UC_DW_27(tc_port)) &
-			     DKL_CMN_UC_DW27_UC_HEALTH, 1))
-			drm_warn(display->drm,
-				 "Timeout waiting TC uC health\n");
+		ret = read_poll_timeout(intel_dkl_phy_read, val,
+					val & DKL_CMN_UC_DW27_UC_HEALTH,
+					100, 1000, false,
+					display, DKL_CMN_UC_DW_27(tc_port));
+		if (ret)
+			drm_warn(display->drm, "Timeout waiting TC uC health\n");
 	}
 }
 
-- 
2.39.5