Re: [PATCH v1 06/12] drm/bridge: cros-ec-anx7688: Use drm_bridge_funcs.atomic_check

From: Dave Stevenson <dave.stevenson@raspberrypi.com>
To: Sam Ravnborg <sam@ravnborg.org>
Cc: dri-devel@lists.freedesktop.org,
	Andrzej Hajda <andrzej.hajda@intel.com>,
	 Neil Armstrong <narmstrong@baylibre.com>,
	Robert Foss <robert.foss@linaro.org>,
	 Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
	Jonas Karlman <jonas@kwiboo.se>,
	 Jernej Skrabec <jernej.skrabec@gmail.com>,
	 Dafna Hirschfeld <dafna.hirschfeld@collabora.com>,
	David Airlie <airlied@linux.ie>,
	 Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>,
	Guenter Roeck <groeck@chromium.org>,
	 chrome-platform@lists.linux.dev,
	Chun-Kuang Hu <chunkuang.hu@kernel.org>,
	 Jitao Shi <jitao.shi@mediatek.com>,
	Thomas Zimmermann <tzimmermann@suse.de>,
	 Arnd Bergmann <arnd@arndb.de>,
	linux-mediatek@lists.infradead.org,
	 Matthias Brugger <matthias.bgg@gmail.com>,
	linux-arm-kernel@lists.infradead.org,
	 Philip Chen <philipchen@chromium.org>,
	linux-renesas-soc@vger.kernel.org,
	 Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>,
	 Enric Balletbo i Serra <enric.balletbo@collabora.com>,
	Cai Huoqing <cai.huoqing@linux.dev>
Subject: Re: [PATCH v1 06/12] drm/bridge: cros-ec-anx7688: Use drm_bridge_funcs.atomic_check
Date: Tue, 19 Jul 2022 15:03:40 +0100	[thread overview]
Message-ID: <CAPY8ntAUS0GMik2=PGeg8209yWjqUxmWV8az=YQczkE-tAw0XQ@mail.gmail.com> (raw)
In-Reply-To: <20220717174454.46616-7-sam@ravnborg.org>

On Sun, 17 Jul 2022 at 18:45, Sam Ravnborg <sam@ravnborg.org> wrote:
>
> Replace the deprecated drm_bridge_funcs.mode_fixup() with
> drm_bridge_funcs.atomic_check().
>
> drm_bridge_funcs.atomic_check() requires the atomic state operations,
> update these to the default implementations.
>
> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>

> Cc: Andrzej Hajda <andrzej.hajda@intel.com>
> Cc: Neil Armstrong <narmstrong@baylibre.com>
> Cc: Robert Foss <robert.foss@linaro.org>
> Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
> Cc: Jonas Karlman <jonas@kwiboo.se>
> Cc: Jernej Skrabec <jernej.skrabec@gmail.com>
> Cc: Benson Leung <bleung@chromium.org>
> Cc: Guenter Roeck <groeck@chromium.org>
> Cc: chrome-platform@lists.linux.dev
> ---
>  drivers/gpu/drm/bridge/cros-ec-anx7688.c | 28 +++++++++++++++---------
>  1 file changed, 18 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/cros-ec-anx7688.c b/drivers/gpu/drm/bridge/cros-ec-anx7688.c
> index 0f6d907432e3..fc19ea87926f 100644
> --- a/drivers/gpu/drm/bridge/cros-ec-anx7688.c
> +++ b/drivers/gpu/drm/bridge/cros-ec-anx7688.c
> @@ -5,6 +5,7 @@
>   * Copyright 2020 Google LLC
>   */
>
> +#include <drm/drm_atomic_state_helper.h>
>  #include <drm/drm_bridge.h>
>  #include <drm/drm_print.h>
>  #include <linux/i2c.h>
> @@ -45,9 +46,10 @@ bridge_to_cros_ec_anx7688(struct drm_bridge *bridge)
>         return container_of(bridge, struct cros_ec_anx7688, bridge);
>  }
>
> -static bool cros_ec_anx7688_bridge_mode_fixup(struct drm_bridge *bridge,
> -                                             const struct drm_display_mode *mode,
> -                                             struct drm_display_mode *adjusted_mode)
> +static int cros_ec_anx7688_bridge_atomic_check(struct drm_bridge *bridge,
> +                                              struct drm_bridge_state *bridge_state,
> +                                              struct drm_crtc_state *crtc_state,
> +                                              struct drm_connector_state *conn_state)
>  {
>         struct cros_ec_anx7688 *anx = bridge_to_cros_ec_anx7688(bridge);
>         int totalbw, requiredbw;
> @@ -56,13 +58,13 @@ static bool cros_ec_anx7688_bridge_mode_fixup(struct drm_bridge *bridge,
>         int ret;
>
>         if (!anx->filter)
> -               return true;
> +               return 0;
>
>         /* Read both regs 0x85 (bandwidth) and 0x86 (lane count). */
>         ret = regmap_bulk_read(anx->regmap, ANX7688_DP_BANDWIDTH_REG, regs, 2);
>         if (ret < 0) {
>                 DRM_ERROR("Failed to read bandwidth/lane count\n");
> -               return false;
> +               return ret;
>         }
>         dpbw = regs[0];
>         lanecount = regs[1];
> @@ -71,28 +73,34 @@ static bool cros_ec_anx7688_bridge_mode_fixup(struct drm_bridge *bridge,
>         if (dpbw > 0x19 || lanecount > 2) {
>                 DRM_ERROR("Invalid bandwidth/lane count (%02x/%d)\n", dpbw,
>                           lanecount);
> -               return false;
> +               return -EINVAL;
>         }
>
>         /* Compute available bandwidth (kHz) */
>         totalbw = dpbw * lanecount * 270000 * 8 / 10;
>
>         /* Required bandwidth (8 bpc, kHz) */
> -       requiredbw = mode->clock * 8 * 3;
> +       requiredbw = crtc_state->mode.clock * 8 * 3;
>
>         DRM_DEBUG_KMS("DP bandwidth: %d kHz (%02x/%d); mode requires %d Khz\n",
>                       totalbw, dpbw, lanecount, requiredbw);
>
>         if (totalbw == 0) {
>                 DRM_ERROR("Bandwidth/lane count are 0, not rejecting modes\n");
> -               return true;
> +               return 0;
>         }
>
> -       return totalbw >= requiredbw;
> +       if (totalbw < requiredbw)
> +               return -EINVAL;
> +
> +       return 0;
>  }
>
>  static const struct drm_bridge_funcs cros_ec_anx7688_bridge_funcs = {
> -       .mode_fixup = cros_ec_anx7688_bridge_mode_fixup,
> +       .atomic_check = cros_ec_anx7688_bridge_atomic_check,
> +       .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
> +       .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
> +       .atomic_reset = drm_atomic_helper_bridge_reset,
>  };
>
>  static int cros_ec_anx7688_bridge_probe(struct i2c_client *client)
> --
> 2.34.1
>