From: Samuel Holland <samuel@sholland.org>
To: Maxime Ripard <mripard@kernel.org>, Chen-Yu Tsai <wens@csie.org>,
David Airlie <airlied@linux.ie>, Daniel Vetter <daniel@ffwll.ch>,
dri-devel@lists.freedesktop.org
Cc: linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org, stable@vger.kernel.org,
Samuel Holland <samuel@sholland.org>
Subject: [PATCH 2/4] drm/sun4i: dsi: Use NULL to signify "no panel"
Date: Tue, 11 Feb 2020 01:28:56 -0600 [thread overview]
Message-ID: <20200211072858.30784-2-samuel@sholland.org> (raw)
In-Reply-To: <20200211072858.30784-1-samuel@sholland.org>
The continued use of an ERR_PTR to signify "no panel" outside of
sun6i_dsi_attach is confusing because it is a double negative. Because
the connector always reports itself as connected, there is also the
possibility of sending an ERR_PTR to drm_panel_get_modes(), which would
crash.
Solve both of these by only storing the panel pointer if it is valid.
Fixes: 133add5b5ad4 ("drm/sun4i: Add Allwinner A31 MIPI-DSI controller support")
Signed-off-by: Samuel Holland <samuel@sholland.org>
---
drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
index c07290541fff..019fdf4ec274 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
@@ -748,7 +748,7 @@ static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder)
phy_configure(dsi->dphy, &opts);
phy_power_on(dsi->dphy);
- if (!IS_ERR(dsi->panel))
+ if (dsi->panel)
drm_panel_prepare(dsi->panel);
/*
@@ -763,7 +763,7 @@ static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder)
* ordering on the panels I've tested it with, so I guess this
* will do for now, until that IP is better understood.
*/
- if (!IS_ERR(dsi->panel))
+ if (dsi->panel)
drm_panel_enable(dsi->panel);
sun6i_dsi_start(dsi, DSI_START_HSC);
@@ -779,7 +779,7 @@ static void sun6i_dsi_encoder_disable(struct drm_encoder *encoder)
DRM_DEBUG_DRIVER("Disabling DSI output\n");
- if (!IS_ERR(dsi->panel)) {
+ if (dsi->panel) {
drm_panel_disable(dsi->panel);
drm_panel_unprepare(dsi->panel);
}
@@ -941,11 +941,13 @@ static int sun6i_dsi_attach(struct mipi_dsi_host *host,
struct mipi_dsi_device *device)
{
struct sun6i_dsi *dsi = host_to_sun6i_dsi(host);
+ struct drm_panel *panel = of_drm_find_panel(device->dev.of_node);
+ if (IS_ERR(panel))
+ return PTR_ERR(panel);
+
+ dsi->panel = panel;
dsi->device = device;
- dsi->panel = of_drm_find_panel(device->dev.of_node);
- if (IS_ERR(dsi->panel))
- return PTR_ERR(dsi->panel);
dev_info(host->dev, "Attached device %s\n", device->name);
--
2.24.1
next prev parent reply other threads:[~2020-02-11 7:29 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-11 7:28 [PATCH 1/4] drm/sun4i: dsi: Remove unused drv from driver context Samuel Holland
2020-02-11 7:28 ` Samuel Holland [this message]
2020-02-11 7:28 ` [PATCH 3/4] drm/sun4i: dsi: Allow binding the host without a panel Samuel Holland
2020-02-15 2:24 ` Samuel Holland
2020-02-11 7:28 ` [PATCH 4/4] drm/sun4i: dsi: Remove incorrect use of runtime PM Samuel Holland
2020-02-11 8:26 ` Maxime Ripard
2020-02-11 15:39 ` Samuel Holland
2020-02-15 2:37 ` Samuel Holland
2020-02-14 15:39 ` Maxime Ripard
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