From: Guennadi Liakhovetski <g.liakhovetski@xxxxxx> Add a V4L2 OF parser, implementing bindings, documented in Documentation/devicetree/bindings/media/video-interfaces.txt. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@xxxxxx> Signed-off-by: Sylwester Nawrocki <s.nawrocki@xxxxxxxxxxx> --- Changes since previous version: - merged into this one all my fixup patches from this series [1]: v4l2-of: Support variable length of data-lanes property v4l2-of: Add v4l2_of_parse_data_lanes() function v4l2-of: Corrected v4l2_of_parse_link() function declaration v4l2_of_parse_link() return value type is int, not void. v4l2-of: Replace "remote" property with "remote-endpoint" [1] https://lkml.org/lkml/2012/12/10/464 --- drivers/media/v4l2-core/Makefile | 3 + drivers/media/v4l2-core/v4l2-of.c | 249 +++++++++++++++++++++++++++++++++++++ include/media/v4l2-of.h | 79 ++++++++++++ 3 files changed, 331 insertions(+) create mode 100644 drivers/media/v4l2-core/v4l2-of.c create mode 100644 include/media/v4l2-of.h diff --git a/drivers/media/v4l2-core/Makefile b/drivers/media/v4l2-core/Makefile index c2d61d4..00f64d6 100644 --- a/drivers/media/v4l2-core/Makefile +++ b/drivers/media/v4l2-core/Makefile @@ -9,6 +9,9 @@ videodev-objs := v4l2-dev.o v4l2-ioctl.o v4l2-device.o v4l2-fh.o \ ifeq ($(CONFIG_COMPAT),y) videodev-objs += v4l2-compat-ioctl32.o endif +ifeq ($(CONFIG_OF),y) + videodev-objs += v4l2-of.o +endif obj-$(CONFIG_VIDEO_DEV) += videodev.o v4l2-int-device.o obj-$(CONFIG_VIDEO_V4L2) += v4l2-common.o diff --git a/drivers/media/v4l2-core/v4l2-of.c b/drivers/media/v4l2-core/v4l2-of.c new file mode 100644 index 0000000..cdac04b --- /dev/null +++ b/drivers/media/v4l2-core/v4l2-of.c @@ -0,0 +1,249 @@ +/* + * V4L2 OF binding parsing library + * + * Copyright (C) 2012 Renesas Electronics Corp. + * Author: Guennadi Liakhovetski <g.liakhovetski@xxxxxx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/slab.h> +#include <linux/types.h> + +#include <media/v4l2-of.h> + +/** + * v4l2_of_parse_mipi_csi2() - parse MIPI CSI-2 bus properties + * @node: pointer to endpoint device_node + * @endpoint: pointer to v4l2_of_endpoint data structure + * + * Return: 0 on success or negative error value otherwise. + */ +int v4l2_of_parse_mipi_csi2(const struct device_node *node, + struct v4l2_of_endpoint *endpoint) +{ + struct v4l2_of_mipi_csi2 *mipi_csi2 = &endpoint->mipi_csi_2; + u32 data_lanes[ARRAY_SIZE(mipi_csi2->data_lanes)]; + struct property *prop; + const __be32 *lane = NULL; + u32 v; + int i = 0; + + prop = of_find_property(node, "data-lanes", NULL); + if (!prop) + return -EINVAL; + do { + lane = of_prop_next_u32(prop, lane, &data_lanes[i]); + } while (lane && i++ < ARRAY_SIZE(data_lanes)); + + mipi_csi2->num_data_lanes = i; + while (i--) + mipi_csi2->data_lanes[i] = data_lanes[i]; + + if (!of_property_read_u32(node, "clock-lanes", &v)) + mipi_csi2->clock_lane = v; + + if (of_get_property(node, "clock-noncontinuous", &v)) + endpoint->mbus_flags |= V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK; + + return 0; +} + +/** + * v4l2_of_parse_parallel_bus() - parse parallel bus properties + * @node: pointer to endpoint device_node + * @endpoint: pointer to v4l2_of_endpoint data structure + */ +void v4l2_of_parse_parallel_bus(const struct device_node *node, + struct v4l2_of_endpoint *endpoint) +{ + unsigned int flags = 0; + u32 v; + + if (WARN_ON(!endpoint)) + return; + + if (!of_property_read_u32(node, "hsync-active", &v)) + flags |= v ? V4L2_MBUS_HSYNC_ACTIVE_HIGH : + V4L2_MBUS_HSYNC_ACTIVE_LOW; + + if (!of_property_read_u32(node, "vsync-active", &v)) + flags |= v ? V4L2_MBUS_VSYNC_ACTIVE_HIGH : + V4L2_MBUS_VSYNC_ACTIVE_LOW; + + if (!of_property_read_u32(node, "pclk-sample", &v)) + flags |= v ? V4L2_MBUS_PCLK_SAMPLE_RISING : + V4L2_MBUS_PCLK_SAMPLE_FALLING; + + if (!of_property_read_u32(node, "field-even-active", &v)) + flags |= v ? V4L2_MBUS_FIELD_EVEN_HIGH : + V4L2_MBUS_FIELD_EVEN_LOW; + if (flags) + endpoint->mbus_type = V4L2_MBUS_PARALLEL; + else + endpoint->mbus_type = V4L2_MBUS_BT656; + + if (!of_property_read_u32(node, "data-active", &v)) + flags |= v ? V4L2_MBUS_DATA_ACTIVE_HIGH : + V4L2_MBUS_DATA_ACTIVE_LOW; + + if (of_get_property(node, "slave-mode", &v)) + flags |= V4L2_MBUS_SLAVE; + + if (!of_property_read_u32(node, "bus-width", &v)) + endpoint->parallel.bus_width = v; + + if (!of_property_read_u32(node, "data-shift", &v)) + endpoint->parallel.data_shift = v; + + endpoint->mbus_flags = flags; +} + +/** + * v4l2_of_parse_endpoint() - parse all endpoint node properties + * @node: pointer to endpoint device_node + * @endpoint: pointer to v4l2_of_endpoint data structure + * + * All properties are optional. If none are found, we don't set any flags. + * This means the port has a static configuration and no properties have + * to be specified explicitly. + * If any properties that identify the bus as parallel are found and + * slave-mode isn't set, we set V4L2_MBUS_MASTER. Similarly, if we recognise + * the bus as serial CSI-2 and clock-noncontinuous isn't set, we set the + * V4L2_MBUS_CSI2_CONTINUOUS_CLOCK flag. + * The caller should hold a reference to @node. + */ +void v4l2_of_parse_endpoint(const struct device_node *node, + struct v4l2_of_endpoint *endpoint) +{ + const struct device_node *port_node = of_get_parent(node); + bool data_lanes_present = false; + + memset(endpoint, 0, sizeof(*endpoint)); + + endpoint->local_node = node; + + /* Doesn't matter, whether the below two calls succeed */ + of_property_read_u32(port_node, "reg", &endpoint->port); + of_property_read_u32(node, "reg", &endpoint->addr); + + v4l2_of_parse_parallel_bus(node, endpoint); + + /* If any parallel bus properties have been found, skip serial ones */ + if (endpoint->parallel.bus_width || endpoint->parallel.data_shift || + endpoint->mbus_flags) { + /* Default parallel bus-master */ + if (!(endpoint->mbus_flags & V4L2_MBUS_SLAVE)) + endpoint->mbus_flags |= V4L2_MBUS_MASTER; + return; + } + + endpoint->mbus_type = V4L2_MBUS_CSI2; + + if (!v4l2_of_parse_mipi_csi2(node, endpoint)) + data_lanes_present = true; + + if ((endpoint->mipi_csi_2.clock_lane || data_lanes_present) && + !(endpoint->mbus_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)) { + /* Default CSI-2: continuous clock */ + endpoint->mbus_flags |= V4L2_MBUS_CSI2_CONTINUOUS_CLOCK; + } +} +EXPORT_SYMBOL(v4l2_of_parse_endpoint); + +/* + * Return a refcounted next "endpoint" DT node. Contrary to the common OF + * practice, we do not drop the reference to previous, users have to do it + * themselves, when they're done with the node. + */ +struct device_node *v4l2_of_get_next_endpoint(const struct device_node *parent, + struct device_node *previous) +{ + struct device_node *child, *port; + + if (!parent) + return NULL; + + if (!previous) { + /* + * If this is the first call, we have to find a port within this + * node + */ + for_each_child_of_node(parent, port) { + if (!of_node_cmp(port->name, "port")) + break; + } + if (port) { + /* Found a port, get a link */ + child = of_get_next_child(port, NULL); + of_node_put(port); + } else { + child = NULL; + } + if (!child) + pr_err("%s(): Invalid DT: %s has no link children!\n", + __func__, parent->name); + } else { + port = of_get_parent(previous); + if (!port) + /* Hm, has someone given us the root node?... */ + return NULL; + + /* Avoid dropping previous refcount to 0 */ + of_node_get(previous); + child = of_get_next_child(port, previous); + if (child) { + of_node_put(port); + return child; + } + + /* No more links under this port, try the next one */ + do { + port = of_get_next_child(parent, port); + if (!port) + return NULL; + } while (of_node_cmp(port->name, "port")); + + /* Pick up the first link on this port */ + child = of_get_next_child(port, NULL); + of_node_put(port); + } + + return child; +} +EXPORT_SYMBOL(v4l2_of_get_next_endpoint); + +/** + * v4l2_of_get_remote_port_parent() - get remote port's parent node + * @node: pointer to local endpoint device_node + * + * Return: Remote device node associated with remote endpoint node linked + * to @node. Use of_node_put() on it when done. + */ +struct device_node *v4l2_of_get_remote_port_parent( + const struct device_node *node) +{ + struct device_node *re, *tmp; + + /* Get remote endpoint DT node. */ + re = of_parse_phandle(node, "remote-endpoint", 0); + if (!re) + return NULL; + + /* Remote port. */ + tmp = of_get_parent(re); + of_node_put(re); + if (!tmp) + return NULL; + + /* Remote device node. */ + re = of_get_parent(tmp); + of_node_put(tmp); + + return re; +} +EXPORT_SYMBOL(v4l2_of_get_remote_port_parent); diff --git a/include/media/v4l2-of.h b/include/media/v4l2-of.h new file mode 100644 index 0000000..1aba3b3 --- /dev/null +++ b/include/media/v4l2-of.h @@ -0,0 +1,79 @@ +/* + * V4L2 OF binding parsing library + * + * Copyright (C) 2012 Renesas Electronics Corp. + * Author: Guennadi Liakhovetski <g.liakhovetski@xxxxxx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + */ +#ifndef _V4L2_OF_H +#define _V4L2_OF_H + +#include <linux/list.h> +#include <linux/types.h> +#include <linux/errno.h> + +#include <media/v4l2-mediabus.h> + +struct device_node; + +struct v4l2_of_mipi_csi2 { + unsigned char data_lanes[4]; + unsigned char clock_lane; + unsigned short num_data_lanes; +}; + +struct v4l2_of_endpoint { + unsigned int port; + unsigned int addr; + struct list_head head; + const struct device_node *local_node; + const __be32 *remote; + enum v4l2_mbus_type mbus_type; + unsigned int mbus_flags; + union { + struct { + unsigned char bus_width; + unsigned char data_shift; + } parallel; + struct v4l2_of_mipi_csi2 mipi_csi_2; + }; +}; + +#ifdef CONFIG_OF +int v4l2_of_parse_mipi_csi2(const struct device_node *node, + struct v4l2_of_endpoint *endpoint); +void v4l2_of_parse_parallel_bus(const struct device_node *node, + struct v4l2_of_endpoint *endpoint); +void v4l2_of_parse_endpoint(const struct device_node *node, + struct v4l2_of_endpoint *link); +struct device_node *v4l2_of_get_next_endpoint(const struct device_node *parent, + struct device_node *previous); +struct device_node *v4l2_of_get_remote_port_parent( + const struct device_node *node); +#else /* CONFIG_OF */ + +static inline int v4l2_of_parse_endpoint(const struct device_node *node, + struct v4l2_of_endpoint *link) +{ + return -ENOSYS; +} + +static inline struct device_node *v4l2_of_get_next_endpoint( + const struct device_node *parent, + struct device_node *previous) +{ + return NULL; +} + +static inline struct device_node *v4l2_of_get_remote_endpoint( + const struct device_node *node) +{ + return NULL; +} + +#endif /* CONFIG_OF */ + +#endif /* _V4L2_OF_H */ -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
