From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiko Stuebner Subject: [PATCH 6/8] drm/dsi: add helper function to find the second host in a dual-dsi setup Date: Mon, 11 Jun 2018 15:35:00 +0200 Message-ID: <20180611133502.1292-7-heiko@sntech.de> References: <20180611133502.1292-1-heiko@sntech.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180611133502.1292-1-heiko-4mtYJXux2i+zQB+pC5nmwQ@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+glpar-linux-rockchip=m.gmane.org-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org To: dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org Cc: mark.rutland-5wv7dgnIgG8@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, architt-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org, Heiko Stuebner , a.hajda-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org, briannorris-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org, hoegsberg-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, philippe.cornu-qxv4g6HH51o@public.gmane.org, yannick.fertre-qxv4g6HH51o@public.gmane.org, linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, nickey.yang-TNX95d0MmH7DzftRWevZcw@public.gmane.org, robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, laurent.pinchart-ryLnwIuWjnjg/C1BVhZhaw@public.gmane.org, seanpaul-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org, mka-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org List-Id: linux-rockchip.vger.kernel.org >From a specified output port of one dsi controller this function allows to iterate over the list of registered dsi controllers trying to find a second instance connected to the same display, like it is used in dual-dsi setups. Signed-off-by: Heiko Stuebner --- drivers/gpu/drm/drm_mipi_dsi.c | 56 ++++++++++++++++++++++++++++++++++ include/drm/drm_mipi_dsi.h | 2 ++ 2 files changed, 58 insertions(+) diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c index bc73b7f5b9fc..ac457d02389c 100644 --- a/drivers/gpu/drm/drm_mipi_dsi.c +++ b/drivers/gpu/drm/drm_mipi_dsi.c @@ -30,6 +30,7 @@ #include #include #include +#include #include #include @@ -282,6 +283,61 @@ struct mipi_dsi_host *of_find_mipi_dsi_host_by_node(struct device_node *node) } EXPORT_SYMBOL(of_find_mipi_dsi_host_by_node); +struct device_node *of_mipi_dsi_find_second_host(struct device_node *first_np, + int port, int endpoint) +{ + struct mipi_dsi_host *first, *host; + struct device_node *remote, *np, *second_np = NULL; + int num = 0; + + first = of_find_mipi_dsi_host_by_node(first_np); + if (!first) { + pr_err("no dsi-host for node %s\n", first_np->full_name); + return ERR_PTR(-ENODEV); + } + + /* output-node of the known dsi-host */ + remote = of_graph_get_remote_node(first_np, port, endpoint); + if (!remote) { + dev_err(first->dev, "no output node found\n"); + return ERR_PTR(-ENODEV); + } + + mutex_lock(&host_lock); + + list_for_each_entry(host, &host_list, list) { + np = of_graph_get_remote_node(host->dev->of_node, + port, endpoint); + + /* found a host connected to this panel */ + if (np == remote) + num++; + + /* found one second host */ + if (host->dev->of_node != first_np) + second_np = host->dev->of_node; + + of_node_put(np); + } + + /* of_node_get the node under host_lock */ + if (num == 2) + of_node_get(second_np); + + mutex_unlock(&host_lock); + + of_node_put(remote); + + if (num > 2) { + dev_err(first->dev, + "too many DSI links for output: %d links\n", num); + return ERR_PTR(-EINVAL); + } + + return second_np; +} +EXPORT_SYMBOL(of_mipi_dsi_find_second_host); + int mipi_dsi_host_register(struct mipi_dsi_host *host) { struct device_node *node; diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h index 4fef19064b0f..89532ae69c91 100644 --- a/include/drm/drm_mipi_dsi.h +++ b/include/drm/drm_mipi_dsi.h @@ -107,6 +107,8 @@ struct mipi_dsi_host { int mipi_dsi_host_register(struct mipi_dsi_host *host); void mipi_dsi_host_unregister(struct mipi_dsi_host *host); struct mipi_dsi_host *of_find_mipi_dsi_host_by_node(struct device_node *node); +struct device_node *of_mipi_dsi_find_second_host(struct device_node *first_np, + int port, int endpoint); /* DSI mode flags */ -- 2.17.0