dri-devel.lists.freedesktop.org archive mirror
 help / color / mirror / Atom feed
From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Sasha Levin <sashal@kernel.org>,
	linux-arm-kernel@lists.infradead.org,
	Maxime Ripard <maxime@cerno.tech>,
	dri-devel@lists.freedesktop.org,
	Samuel Holland <samuel@sholland.org>
Subject: [PATCH AUTOSEL 5.4 042/108] drm/sun4i: dsi: Use NULL to signify "no panel"
Date: Sat, 11 Apr 2020 19:08:37 -0400	[thread overview]
Message-ID: <20200411230943.24951-42-sashal@kernel.org> (raw)
In-Reply-To: <20200411230943.24951-1-sashal@kernel.org>

From: Samuel Holland <samuel@sholland.org>

[ Upstream commit 0e4e3fb4901d19f49e5c0a582f383b10dda8d1c5 ]

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>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211072858.30784-2-samuel@sholland.org
Signed-off-by: Sasha Levin <sashal@kernel.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 f83522717488a..d2ade0ad67708 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);
 
-- 
2.20.1

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

  parent reply	other threads:[~2020-04-11 23:10 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20200411230943.24951-1-sashal@kernel.org>
2020-04-11 23:08 ` [PATCH AUTOSEL 5.4 012/108] drm/amd/display: Explicitly disable triplebuffer flips Sasha Levin
2020-04-11 23:08 ` [PATCH AUTOSEL 5.4 022/108] drm/tegra: dc: Release PM and RGB output when client's registration fails Sasha Levin
2020-04-11 23:08 ` [PATCH AUTOSEL 5.4 024/108] drm/amd/display: Stop if retimer is not available Sasha Levin
2020-04-11 23:08 ` [PATCH AUTOSEL 5.4 026/108] drm/amd/display: writing stereo polarity register if swapped Sasha Levin
2020-04-11 23:08 ` [PATCH AUTOSEL 5.4 029/108] drm/amd/display: Fix default logger mask definition Sasha Levin
2020-04-11 23:08 ` [PATCH AUTOSEL 5.4 032/108] drm/amd/display: Only round InfoFrame refresh rates Sasha Levin
2020-04-11 23:08 ` Sasha Levin [this message]
2020-04-11 23:08 ` [PATCH AUTOSEL 5.4 048/108] drm/omap: fix possible object reference leak Sasha Levin
2020-04-11 23:08 ` [PATCH AUTOSEL 5.4 051/108] drm/stm: ltdc: check crtc state before enabling LIE Sasha Levin
2020-04-11 23:08 ` [PATCH AUTOSEL 5.4 052/108] fbdev: potential information leak in do_fb_ioctl() Sasha Levin
2020-04-11 23:08 ` [PATCH AUTOSEL 5.4 053/108] drm/crc: Actually allow to change the crc source Sasha Levin
2020-04-11 23:08 ` [PATCH AUTOSEL 5.4 054/108] drm/amdgpu: fix parentheses in amdgpu_vm_update_ptes Sasha Levin
2020-04-11 23:08 ` [PATCH AUTOSEL 5.4 055/108] drm/amd/display: dc_get_vmid_use_vector() crashes when get called Sasha Levin
2020-04-11 23:08 ` [PATCH AUTOSEL 5.4 061/108] drm/amd/display: dal_ddc_i2c_payloads_create can fail causing panic Sasha Levin
2020-04-11 23:08 ` [PATCH AUTOSEL 5.4 062/108] drm/amd/display: System crashes when add_ptb_to_table() gets called Sasha Levin
2020-04-11 23:08 ` [PATCH AUTOSEL 5.4 063/108] drm/omap: dss: Cleanup DSS ports on initialisation failure Sasha Levin
2020-04-11 23:09 ` [PATCH AUTOSEL 5.4 072/108] drm/msm: fix leaks if initialization fails Sasha Levin
2020-04-11 23:09 ` [PATCH AUTOSEL 5.4 073/108] drm/msm/a5xx: Always set an OPP supported hardware value Sasha Levin
2020-04-11 23:09 ` [PATCH AUTOSEL 5.4 074/108] drm/msm: devcoredump should dump MSM_SUBMIT_BO_DUMP buffers Sasha Levin
2020-04-11 23:09 ` [PATCH AUTOSEL 5.4 108/108] PCI: Use ioremap(), not phys_to_virt() for platform ROM Sasha Levin

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200411230943.24951-42-sashal@kernel.org \
    --to=sashal@kernel.org \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=maxime@cerno.tech \
    --cc=samuel@sholland.org \
    --cc=stable@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).