drm/i915: Fix AUX power domain toggling across TypeC mode resets

commit d96536f0fe699729a0974eb5b65eb0d87cc747e1 upstream.

Make sure to select the port's AUX power domain while holding the TC
port lock. The domain depends on the port's current TC mode, which may
get changed under us if we're not holding the lock.

This was left out from
commit 8c10e2262663 ("drm/i915: Keep the TypeC port mode fixed for detect/AUX transfers")

Cc: <stable@vger.kernel.org> # v5.4+
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200514204553.27193-1-imre.deak@intel.com
(cherry picked from commit ae9b6cfe1352da25931bce3ea4acfd4dc1ac8a85)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 4ab6531..2efc317 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -1292,8 +1292,7 @@ intel_dp_aux_xfer(struct intel_dp *intel_dp,
        bool is_tc_port = intel_phy_is_tc(i915, phy);
        i915_reg_t ch_ctl, ch_data[5];
        u32 aux_clock_divider;
-       enum intel_display_power_domain aux_domain =
-               intel_aux_power_domain(intel_dig_port);
+       enum intel_display_power_domain aux_domain;
        intel_wakeref_t aux_wakeref;
        intel_wakeref_t pps_wakeref;
        int i, ret, recv_bytes;
@@ -1308,6 +1307,8 @@ intel_dp_aux_xfer(struct intel_dp *intel_dp,
        if (is_tc_port)
                intel_tc_port_lock(intel_dig_port);
 
+       aux_domain = intel_aux_power_domain(intel_dig_port);
+
        aux_wakeref = intel_display_power_get(i915, aux_domain);
        pps_wakeref = pps_lock(intel_dp);