If the display is not enable()d, then we aren't holding a runtime PM
reference here. Thus, it's easy to accidentally cause a hang, if user
space is poking around at /dev/drm_dp_aux0 at the "wrong" time.
Let's get a runtime PM reference, and check that we "see" the panel.
Don't force any panel power-up, etc., because that can be intrusive, and
that's not what other drivers do (see
drivers/gpu/drm/bridge/ti-sn65dsi86.c and
drivers/gpu/drm/bridge/parade-ps8640.c.)
Fixes: 0d97ad03f422 ("drm/bridge: analogix_dp: Remove duplicated code")
Cc: <stable(a)vger.kernel.org>
Cc: Tomeu Vizoso <tomeu.vizoso(a)collabora.com>
Signed-off-by: Brian Norris <briannorris(a)chromium.org>
---
Changes in v3:
- Avoid panel power-up; just check for HPD state, and let the rest
happen "as-is" (e.g., time out, if the caller hasn't prepared things
properly)
Changes in v2:
- Fix spelling in Subject
- DRM_DEV_ERROR() -> drm_err()
- Propagate errors from un-analogix_dp_prepare_panel()
drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
index b7d2e4449cfa..16be279aed2c 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
@@ -1632,8 +1632,19 @@ static ssize_t analogix_dpaux_transfer(struct drm_dp_aux *aux,
struct drm_dp_aux_msg *msg)
{
struct analogix_dp_device *dp = to_dp(aux);
+ int ret;
+
+ pm_runtime_get_sync(dp->dev);
+
+ ret = analogix_dp_detect_hpd(dp);
+ if (ret)
+ goto out;
- return analogix_dp_transfer(dp, msg);
+ ret = analogix_dp_transfer(dp, msg);
+out:
+ pm_runtime_put(dp->dev);
+
+ return ret;
}
struct analogix_dp_device *
--
2.35.1.265.g69c8d7142f-goog
The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From d06b1cf28297e27127d3da54753a3a01a2fa2f28 Mon Sep 17 00:00:00 2001
From: Robert Hancock <robert.hancock(a)calian.com>
Date: Wed, 12 Jan 2022 13:42:14 -0600
Subject: [PATCH] serial: 8250: of: Fix mapped region size when using
reg-offset property
8250_of supports a reg-offset property which is intended to handle
cases where the device registers start at an offset inside the region
of memory allocated to the device. The Xilinx 16550 UART, for which this
support was initially added, requires this. However, the code did not
adjust the overall size of the mapped region accordingly, causing the
driver to request an area of memory past the end of the device's
allocation. For example, if the UART was allocated an address of
0xb0130000, size of 0x10000 and reg-offset of 0x1000 in the device
tree, the region of memory reserved was b0131000-b0140fff, which caused
the driver for the region starting at b0140000 to fail to probe.
Fix this by subtracting reg-offset from the mapped region size.
Fixes: b912b5e2cfb3 ([POWERPC] Xilinx: of_serial support for Xilinx uart 16550.)
Cc: stable <stable(a)vger.kernel.org>
Signed-off-by: Robert Hancock <robert.hancock(a)calian.com>
Link: https://lore.kernel.org/r/20220112194214.881844-1-robert.hancock@calian.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/tty/serial/8250/8250_of.c b/drivers/tty/serial/8250/8250_of.c
index bce28729dd7b..be8626234627 100644
--- a/drivers/tty/serial/8250/8250_of.c
+++ b/drivers/tty/serial/8250/8250_of.c
@@ -83,8 +83,17 @@ static int of_platform_serial_setup(struct platform_device *ofdev,
port->mapsize = resource_size(&resource);
/* Check for shifted address mapping */
- if (of_property_read_u32(np, "reg-offset", &prop) == 0)
+ if (of_property_read_u32(np, "reg-offset", &prop) == 0) {
+ if (prop >= port->mapsize) {
+ dev_warn(&ofdev->dev, "reg-offset %u exceeds region size %pa\n",
+ prop, &port->mapsize);
+ ret = -EINVAL;
+ goto err_unprepare;
+ }
+
port->mapbase += prop;
+ port->mapsize -= prop;
+ }
port->iotype = UPIO_MEM;
if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {