drm/i915/power: use generic poll_timeout_us() instead of wait_for()

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.

Reviewed-by: Jouni Högander <jouni.hogander@intel.com>
Link: https://lore.kernel.org/r/900680516b047ae32e3298b5cdbcede0393e0466.1756383233.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

diff --git a/drivers/gpu/drm/i915/display/intel_display_power.c b/drivers/gpu/drm/i915/display/intel_display_power.c
index d1d3b6f89e2a23e056d17e0fff6c80ea9e6f4e82..7340d5a7167300417c6e0282d6ca387b3bddcc80 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_display_power.c
+++ b/drivers/gpu/drm/i915/display/intel_display_power.c
@@ -3,6 +3,7 @@
  * Copyright © 2019 Intel Corporation
  */
 
+#include <linux/iopoll.h>
 #include <linux/string_helpers.h>
 
 #include "soc/intel_dram.h"
@@ -1310,8 +1311,10 @@ static void hsw_disable_lcpll(struct intel_display *display,
        hsw_write_dcomp(display, val);
        ndelay(100);
 
-       if (wait_for((hsw_read_dcomp(display) &
-                     D_COMP_RCOMP_IN_PROGRESS) == 0, 1))
+       ret = poll_timeout_us(val = hsw_read_dcomp(display),
+                             (val & D_COMP_RCOMP_IN_PROGRESS) == 0,
+                             100, 1000, false);
+       if (ret)
                drm_err(display->drm, "D_COMP RCOMP still in progress\n");
 
        if (allow_power_down) {