[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <1486377768.3005.34.camel@pengutronix.de>
Date: Mon, 06 Feb 2017 11:42:48 +0100
From: Philipp Zabel <p.zabel@...gutronix.de>
To: Rob Herring <robh@...nel.org>
Cc: David Airlie <airlied@...ux.ie>,
Daniel Vetter <daniel.vetter@...el.com>,
Sean Paul <seanpaul@...omium.org>,
dri-devel@...ts.freedesktop.org, devicetree@...r.kernel.org,
linux-kernel@...r.kernel.org,
Frank Rowand <frowand.list@...il.com>,
Boris Brezillon <boris.brezillon@...e-electrons.com>,
Archit Taneja <architt@...eaurora.org>,
Jingoo Han <jingoohan1@...il.com>,
Inki Dae <inki.dae@...sung.com>,
Joonyoung Shim <jy0922.shim@...sung.com>,
Seung-Woo Kim <sw0312.kim@...sung.com>,
Kyungmin Park <kyungmin.park@...sung.com>,
Kukjin Kim <kgene@...nel.org>,
Krzysztof Kozlowski <krzk@...nel.org>,
Javier Martinez Canillas <javier@....samsung.com>,
Stefan Agner <stefan@...er.ch>,
Alison Wang <alison.wang@...escale.com>,
Xinliang Liu <z.liuxinliang@...ilicon.com>,
Rongrong Zou <zourongrong@...il.com>,
Xinwei Kong <kong.kongxinwei@...ilicon.com>,
Chen Feng <puck.chen@...ilicon.com>,
CK Hu <ck.hu@...iatek.com>,
Matthias Brugger <matthias.bgg@...il.com>,
Marek Vasut <marex@...x.de>,
Mark Yao <mark.yao@...k-chips.com>,
Heiko Stuebner <heiko@...ech.de>,
Maxime Ripard <maxime.ripard@...e-electrons.com>,
Chen-Yu Tsai <wens@...e.org>,
Liviu Dudau <liviu.dudau@....com>,
Mali DP Maintainers <malidp@...s.arm.com>,
Neil Armstrong <narmstrong@...libre.com>,
Carlo Caione <carlo@...one.org>,
Kevin Hilman <khilman@...libre.com>,
Rob Clark <robdclark@...il.com>, Jyri Sarha <jsarha@...com>,
Tomi Valkeinen <tomi.valkeinen@...com>,
Eric Anholt <eric@...olt.net>,
Russell King <rmk+kernel@...linux.org.uk>
Subject: Re: [PATCH 2/5] drm: of: introduce drm_of_find_panel_or_bridge
On Fri, 2017-02-03 at 21:36 -0600, Rob Herring wrote:
> Many drivers have a common pattern of searching the OF graph for either an
> attached panel or bridge and then finding the DRM struct for the panel
> or bridge. Also, most drivers need to handle deferred probing when the
> DRM device is not yet instantiated. Create a common function,
> drm_of_find_panel_or_bridge, to find the connected node and the
> associated DRM panel or bridge device.
>
> Signed-off-by: Rob Herring <robh@...nel.org>
> ---
> drivers/gpu/drm/drm_of.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++
> include/drm/drm_of.h | 13 +++++++++++++
> 2 files changed, 63 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_of.c b/drivers/gpu/drm/drm_of.c
> index 47848ed8ca48..b29ce2f52113 100644
> --- a/drivers/gpu/drm/drm_of.c
> +++ b/drivers/gpu/drm/drm_of.c
> @@ -3,7 +3,9 @@
> #include <linux/list.h>
> #include <linux/of_graph.h>
> #include <drm/drmP.h>
> +#include <drm/drm_bridge.h>
> #include <drm/drm_crtc.h>
> +#include <drm/drm_panel.h>
> #include <drm/drm_of.h>
>
> static void drm_release_of(struct device *dev, void *data)
> @@ -207,3 +209,51 @@ int drm_of_encoder_active_endpoint(struct device_node *node,
> return -EINVAL;
> }
> EXPORT_SYMBOL_GPL(drm_of_encoder_active_endpoint);
> +
> +/*
> + * drm_of_find_panel_or_bridge - return connected panel or bridge device
> + * @np: device tree node containing encoder input ports
> + * @panel: pointer to hold returned drm_panel
> + * @bridge: pointer to hold returned drm_bridge
> + *
> + * Given a DT node's port and endpoint number, find the connected node and
> + * return either the associated struct drm_panel or drm_bridge device.
Add a commend that at least one of panel, bridge must be set?
> + * Returns zero if successful, or one of the standard error codes if it fails.
> + */
> +int drm_of_find_panel_or_bridge(const struct device_node *np,
> + int port, int endpoint,
> + struct drm_panel **panel,
> + struct drm_bridge **bridge)
> +{
> + int ret = -ENODEV;
This is only returned if !panel && !bridge. I'd consider this invalid
usage of this function, so maybe use -EINVAL?
> + struct device_node *remote;
> +
> + remote = of_graph_get_remote_node(np, port, endpoint);
> + if (!remote)
> + return -ENODEV;
> +
> + if (bridge)
> + *bridge = NULL;
I would move this ^ ...
> + if (panel) {
> + *panel = of_drm_find_panel(remote);
> + if (*panel) {
... here.
> + ret = 0;
> + goto out_put;
> + }
> + ret = -EPROBE_DEFER;
> + }
> +
> + if (bridge) {
> + *bridge = of_drm_find_bridge(remote);
> + if (*bridge)
> + ret = 0;
> + else
> + ret = -EPROBE_DEFER;
> + }
> +out_put:
> + of_node_put(remote);
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(drm_of_find_panel_or_bridge);
> diff --git a/include/drm/drm_of.h b/include/drm/drm_of.h
> index 26a64805cc15..f86507f0599b 100644
> --- a/include/drm/drm_of.h
> +++ b/include/drm/drm_of.h
> @@ -8,6 +8,8 @@ struct component_match;
> struct device;
> struct drm_device;
> struct drm_encoder;
> +struct drm_panel;
> +struct drm_bridge;
> struct device_node;
>
> #ifdef CONFIG_OF
> @@ -23,6 +25,10 @@ extern int drm_of_component_probe(struct device *dev,
> extern int drm_of_encoder_active_endpoint(struct device_node *node,
> struct drm_encoder *encoder,
> struct of_endpoint *endpoint);
> +extern int drm_of_find_panel_or_bridge(const struct device_node *np,
> + int port, int endpoint,
> + struct drm_panel **panel,
> + struct drm_bridge **bridge);
> #else
> static inline uint32_t drm_of_find_possible_crtcs(struct drm_device *dev,
> struct device_node *port)
> @@ -52,6 +58,13 @@ static inline int drm_of_encoder_active_endpoint(struct device_node *node,
> {
> return -EINVAL;
> }
> +static inline int drm_of_find_panel_or_bridge(const struct device_node *np,
> + int port, int endpoint,
> + struct drm_panel **panel,
> + struct drm_bridge **bridge)
> +{
> + return -EINVAL;
> +}
> #endif
>
> static inline int drm_of_encoder_active_endpoint_id(struct device_node *node,
regards
Philipp
Powered by blists - more mailing lists