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author | Sakari Ailus <sakari.ailus@linux.intel.com> | 2016-08-12 08:05:51 -0300 |
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committer | Mauro Carvalho Chehab <mchehab@s-opensource.com> | 2017-06-06 09:25:16 -0300 |
commit | ca50c197bd9610ea984cfc0dc6855f183cbb46f8 (patch) | |
tree | 289f43018781f88f6dfe878980c3738f857c3624 | |
parent | 614d651e1abda005ec9df5accef4b02aafcdf1ed (diff) | |
download | linux-stable-ca50c197bd9610ea984cfc0dc6855f183cbb46f8.tar.gz linux-stable-ca50c197bd9610ea984cfc0dc6855f183cbb46f8.tar.bz2 linux-stable-ca50c197bd9610ea984cfc0dc6855f183cbb46f8.zip |
[media] v4l: fwnode: Support generic fwnode for parsing standardised properties
The fwnode_handle is a more generic way than OF device_node to describe
firmware nodes. Instead of the OF API, use more generic fwnode API to
obtain the same information.
As the V4L2 fwnode support will be required by a small minority of e.g.
ACPI based systems (the same might actually go for OF), make this a module
instead of embedding it in the videodev module.
The origins of the V4L2 fwnode framework is in the V4L2 OF framework.
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Hans Verkuil <hans.verkuil@cisco.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
-rw-r--r-- | drivers/media/v4l2-core/Kconfig | 3 | ||||
-rw-r--r-- | drivers/media/v4l2-core/Makefile | 1 | ||||
-rw-r--r-- | drivers/media/v4l2-core/v4l2-fwnode.c | 345 | ||||
-rw-r--r-- | include/media/v4l2-fwnode.h | 104 |
4 files changed, 453 insertions, 0 deletions
diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig index 6b1b78ff1417..a35c33686abf 100644 --- a/drivers/media/v4l2-core/Kconfig +++ b/drivers/media/v4l2-core/Kconfig @@ -55,6 +55,9 @@ config V4L2_FLASH_LED_CLASS When in doubt, say N. +config V4L2_FWNODE + tristate + # Used by drivers that need Videobuf modules config VIDEOBUF_GEN tristate diff --git a/drivers/media/v4l2-core/Makefile b/drivers/media/v4l2-core/Makefile index 795a5352761d..cf77a6328feb 100644 --- a/drivers/media/v4l2-core/Makefile +++ b/drivers/media/v4l2-core/Makefile @@ -13,6 +13,7 @@ endif ifeq ($(CONFIG_OF),y) videodev-objs += v4l2-of.o endif +obj-$(CONFIG_V4L2_FWNODE) += v4l2-fwnode.o ifeq ($(CONFIG_TRACEPOINTS),y) videodev-objs += vb2-trace.o v4l2-trace.o endif diff --git a/drivers/media/v4l2-core/v4l2-fwnode.c b/drivers/media/v4l2-core/v4l2-fwnode.c new file mode 100644 index 000000000000..153c53ca3925 --- /dev/null +++ b/drivers/media/v4l2-core/v4l2-fwnode.c @@ -0,0 +1,345 @@ +/* + * V4L2 fwnode binding parsing library + * + * The origins of the V4L2 fwnode library are in V4L2 OF library that + * formerly was located in v4l2-of.c. + * + * Copyright (c) 2016 Intel Corporation. + * Author: Sakari Ailus <sakari.ailus@linux.intel.com> + * + * Copyright (C) 2012 - 2013 Samsung Electronics Co., Ltd. + * Author: Sylwester Nawrocki <s.nawrocki@samsung.com> + * + * Copyright (C) 2012 Renesas Electronics Corp. + * Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de> + * + * 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/acpi.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/property.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/types.h> + +#include <media/v4l2-fwnode.h> + +static int v4l2_fwnode_endpoint_parse_csi_bus(struct fwnode_handle *fwnode, + struct v4l2_fwnode_endpoint *vep) +{ + struct v4l2_fwnode_bus_mipi_csi2 *bus = &vep->bus.mipi_csi2; + bool have_clk_lane = false; + unsigned int flags = 0, lanes_used = 0; + unsigned int i; + u32 v; + int rval; + + rval = fwnode_property_read_u32_array(fwnode, "data-lanes", NULL, 0); + if (rval > 0) { + u32 array[ARRAY_SIZE(bus->data_lanes)]; + + bus->num_data_lanes = + min_t(int, ARRAY_SIZE(bus->data_lanes), rval); + + fwnode_property_read_u32_array(fwnode, "data-lanes", array, + bus->num_data_lanes); + + for (i = 0; i < bus->num_data_lanes; i++) { + if (lanes_used & BIT(array[i])) + pr_warn("duplicated lane %u in data-lanes\n", + array[i]); + lanes_used |= BIT(array[i]); + + bus->data_lanes[i] = array[i]; + } + } + + rval = fwnode_property_read_u32_array(fwnode, "lane-polarities", NULL, + 0); + if (rval > 0) { + u32 array[ARRAY_SIZE(bus->lane_polarities)]; + + if (rval < 1 + bus->num_data_lanes /* clock + data */) { + pr_warn("too few lane-polarities entries (need %u, got %u)\n", + 1 + bus->num_data_lanes, rval); + return -EINVAL; + } + + fwnode_property_read_u32_array(fwnode, "lane-polarities", array, + 1 + bus->num_data_lanes); + + for (i = 0; i < 1 + bus->num_data_lanes; i++) + bus->lane_polarities[i] = array[i]; + } + + if (!fwnode_property_read_u32(fwnode, "clock-lanes", &v)) { + if (lanes_used & BIT(v)) + pr_warn("duplicated lane %u in clock-lanes\n", v); + lanes_used |= BIT(v); + + bus->clock_lane = v; + have_clk_lane = true; + } + + if (fwnode_property_present(fwnode, "clock-noncontinuous")) + flags |= V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK; + else if (have_clk_lane || bus->num_data_lanes > 0) + flags |= V4L2_MBUS_CSI2_CONTINUOUS_CLOCK; + + bus->flags = flags; + vep->bus_type = V4L2_MBUS_CSI2; + + return 0; +} + +static void v4l2_fwnode_endpoint_parse_parallel_bus( + struct fwnode_handle *fwnode, struct v4l2_fwnode_endpoint *vep) +{ + struct v4l2_fwnode_bus_parallel *bus = &vep->bus.parallel; + unsigned int flags = 0; + u32 v; + + if (!fwnode_property_read_u32(fwnode, "hsync-active", &v)) + flags |= v ? V4L2_MBUS_HSYNC_ACTIVE_HIGH : + V4L2_MBUS_HSYNC_ACTIVE_LOW; + + if (!fwnode_property_read_u32(fwnode, "vsync-active", &v)) + flags |= v ? V4L2_MBUS_VSYNC_ACTIVE_HIGH : + V4L2_MBUS_VSYNC_ACTIVE_LOW; + + if (!fwnode_property_read_u32(fwnode, "field-even-active", &v)) + flags |= v ? V4L2_MBUS_FIELD_EVEN_HIGH : + V4L2_MBUS_FIELD_EVEN_LOW; + if (flags) + vep->bus_type = V4L2_MBUS_PARALLEL; + else + vep->bus_type = V4L2_MBUS_BT656; + + if (!fwnode_property_read_u32(fwnode, "pclk-sample", &v)) + flags |= v ? V4L2_MBUS_PCLK_SAMPLE_RISING : + V4L2_MBUS_PCLK_SAMPLE_FALLING; + + if (!fwnode_property_read_u32(fwnode, "data-active", &v)) + flags |= v ? V4L2_MBUS_DATA_ACTIVE_HIGH : + V4L2_MBUS_DATA_ACTIVE_LOW; + + if (fwnode_property_present(fwnode, "slave-mode")) + flags |= V4L2_MBUS_SLAVE; + else + flags |= V4L2_MBUS_MASTER; + + if (!fwnode_property_read_u32(fwnode, "bus-width", &v)) + bus->bus_width = v; + + if (!fwnode_property_read_u32(fwnode, "data-shift", &v)) + bus->data_shift = v; + + if (!fwnode_property_read_u32(fwnode, "sync-on-green-active", &v)) + flags |= v ? V4L2_MBUS_VIDEO_SOG_ACTIVE_HIGH : + V4L2_MBUS_VIDEO_SOG_ACTIVE_LOW; + + bus->flags = flags; + +} + +/** + * v4l2_fwnode_endpoint_parse() - parse all fwnode node properties + * @fwnode: pointer to the endpoint's fwnode handle + * @vep: pointer to the V4L2 fwnode 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 @fwnode. + * + * NOTE: This function does not parse properties the size of which is variable + * without a low fixed limit. Please use v4l2_fwnode_endpoint_alloc_parse() in + * new drivers instead. + * + * Return: 0 on success or a negative error code on failure. + */ +int v4l2_fwnode_endpoint_parse(struct fwnode_handle *fwnode, + struct v4l2_fwnode_endpoint *vep) +{ + int rval; + + fwnode_graph_parse_endpoint(fwnode, &vep->base); + + /* Zero fields from bus_type to until the end */ + memset(&vep->bus_type, 0, sizeof(*vep) - + offsetof(typeof(*vep), bus_type)); + + rval = v4l2_fwnode_endpoint_parse_csi_bus(fwnode, vep); + if (rval) + return rval; + /* + * Parse the parallel video bus properties only if none + * of the MIPI CSI-2 specific properties were found. + */ + if (vep->bus.mipi_csi2.flags == 0) + v4l2_fwnode_endpoint_parse_parallel_bus(fwnode, vep); + + return 0; +} +EXPORT_SYMBOL_GPL(v4l2_fwnode_endpoint_parse); + +/* + * v4l2_fwnode_endpoint_free() - free the V4L2 fwnode acquired by + * v4l2_fwnode_endpoint_alloc_parse() + * @vep - the V4L2 fwnode the resources of which are to be released + * + * It is safe to call this function with NULL argument or on a V4L2 fwnode the + * parsing of which failed. + */ +void v4l2_fwnode_endpoint_free(struct v4l2_fwnode_endpoint *vep) +{ + if (IS_ERR_OR_NULL(vep)) + return; + + kfree(vep->link_frequencies); + kfree(vep); +} +EXPORT_SYMBOL_GPL(v4l2_fwnode_endpoint_free); + +/** + * v4l2_fwnode_endpoint_alloc_parse() - parse all fwnode node properties + * @fwnode: pointer to the endpoint's fwnode handle + * + * 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 @fwnode. + * + * v4l2_fwnode_endpoint_alloc_parse() has two important differences to + * v4l2_fwnode_endpoint_parse(): + * + * 1. It also parses variable size data. + * + * 2. The memory it has allocated to store the variable size data must be freed + * using v4l2_fwnode_endpoint_free() when no longer needed. + * + * Return: Pointer to v4l2_fwnode_endpoint if successful, on an error pointer + * on error. + */ +struct v4l2_fwnode_endpoint *v4l2_fwnode_endpoint_alloc_parse( + struct fwnode_handle *fwnode) +{ + struct v4l2_fwnode_endpoint *vep; + int rval; + + vep = kzalloc(sizeof(*vep), GFP_KERNEL); + if (!vep) + return ERR_PTR(-ENOMEM); + + rval = v4l2_fwnode_endpoint_parse(fwnode, vep); + if (rval < 0) + goto out_err; + + rval = fwnode_property_read_u64_array(fwnode, "link-frequencies", + NULL, 0); + if (rval < 0) + goto out_err; + + vep->link_frequencies = + kmalloc_array(rval, sizeof(*vep->link_frequencies), GFP_KERNEL); + if (!vep->link_frequencies) { + rval = -ENOMEM; + goto out_err; + } + + vep->nr_of_link_frequencies = rval; + + rval = fwnode_property_read_u64_array(fwnode, "link-frequencies", + vep->link_frequencies, + vep->nr_of_link_frequencies); + if (rval < 0) + goto out_err; + + return vep; + +out_err: + v4l2_fwnode_endpoint_free(vep); + return ERR_PTR(rval); +} +EXPORT_SYMBOL_GPL(v4l2_fwnode_endpoint_alloc_parse); + +/** + * v4l2_fwnode_endpoint_parse_link() - parse a link between two endpoints + * @__fwnode: pointer to the endpoint's fwnode at the local end of the link + * @link: pointer to the V4L2 fwnode link data structure + * + * Fill the link structure with the local and remote nodes and port numbers. + * The local_node and remote_node fields are set to point to the local and + * remote port's parent nodes respectively (the port parent node being the + * parent node of the port node if that node isn't a 'ports' node, or the + * grand-parent node of the port node otherwise). + * + * A reference is taken to both the local and remote nodes, the caller must use + * v4l2_fwnode_endpoint_put_link() to drop the references when done with the + * link. + * + * Return: 0 on success, or -ENOLINK if the remote endpoint fwnode can't be + * found. + */ +int v4l2_fwnode_parse_link(struct fwnode_handle *__fwnode, + struct v4l2_fwnode_link *link) +{ + const char *port_prop = is_of_node(__fwnode) ? "reg" : "port"; + struct fwnode_handle *fwnode; + + memset(link, 0, sizeof(*link)); + + fwnode = fwnode_get_parent(__fwnode); + fwnode_property_read_u32(fwnode, port_prop, &link->local_port); + fwnode = fwnode_get_next_parent(fwnode); + if (is_of_node(fwnode) && + of_node_cmp(to_of_node(fwnode)->name, "ports") == 0) + fwnode = fwnode_get_next_parent(fwnode); + link->local_node = fwnode; + + fwnode = fwnode_graph_get_remote_endpoint(__fwnode); + if (!fwnode) { + fwnode_handle_put(fwnode); + return -ENOLINK; + } + + fwnode = fwnode_get_parent(fwnode); + fwnode_property_read_u32(fwnode, port_prop, &link->remote_port); + fwnode = fwnode_get_next_parent(fwnode); + if (is_of_node(fwnode) && + of_node_cmp(to_of_node(fwnode)->name, "ports") == 0) + fwnode = fwnode_get_next_parent(fwnode); + link->remote_node = fwnode; + + return 0; +} +EXPORT_SYMBOL_GPL(v4l2_fwnode_parse_link); + +/** + * v4l2_fwnode_put_link() - drop references to nodes in a link + * @link: pointer to the V4L2 fwnode link data structure + * + * Drop references to the local and remote nodes in the link. This function + * must be called on every link parsed with v4l2_fwnode_parse_link(). + */ +void v4l2_fwnode_put_link(struct v4l2_fwnode_link *link) +{ + fwnode_handle_put(link->local_node); + fwnode_handle_put(link->remote_node); +} +EXPORT_SYMBOL_GPL(v4l2_fwnode_put_link); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Sakari Ailus <sakari.ailus@linux.intel.com>"); +MODULE_AUTHOR("Sylwester Nawrocki <s.nawrocki@samsung.com>"); +MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>"); diff --git a/include/media/v4l2-fwnode.h b/include/media/v4l2-fwnode.h new file mode 100644 index 000000000000..ecc1233a873e --- /dev/null +++ b/include/media/v4l2-fwnode.h @@ -0,0 +1,104 @@ +/* + * V4L2 fwnode binding parsing library + * + * Copyright (c) 2016 Intel Corporation. + * Author: Sakari Ailus <sakari.ailus@linux.intel.com> + * + * Copyright (C) 2012 - 2013 Samsung Electronics Co., Ltd. + * Author: Sylwester Nawrocki <s.nawrocki@samsung.com> + * + * Copyright (C) 2012 Renesas Electronics Corp. + * Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de> + * + * 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_FWNODE_H +#define _V4L2_FWNODE_H + +#include <linux/errno.h> +#include <linux/fwnode.h> +#include <linux/list.h> +#include <linux/types.h> + +#include <media/v4l2-mediabus.h> + +struct fwnode_handle; + +/** + * struct v4l2_fwnode_bus_mipi_csi2 - MIPI CSI-2 bus data structure + * @flags: media bus (V4L2_MBUS_*) flags + * @data_lanes: an array of physical data lane indexes + * @clock_lane: physical lane index of the clock lane + * @num_data_lanes: number of data lanes + * @lane_polarities: polarity of the lanes. The order is the same of + * the physical lanes. + */ +struct v4l2_fwnode_bus_mipi_csi2 { + unsigned int flags; + unsigned char data_lanes[4]; + unsigned char clock_lane; + unsigned short num_data_lanes; + bool lane_polarities[5]; +}; + +/** + * struct v4l2_fwnode_bus_parallel - parallel data bus data structure + * @flags: media bus (V4L2_MBUS_*) flags + * @bus_width: bus width in bits + * @data_shift: data shift in bits + */ +struct v4l2_fwnode_bus_parallel { + unsigned int flags; + unsigned char bus_width; + unsigned char data_shift; +}; + +/** + * struct v4l2_fwnode_endpoint - the endpoint data structure + * @base: fwnode endpoint of the v4l2_fwnode + * @bus_type: bus type + * @bus: bus configuration data structure + * @link_frequencies: array of supported link frequencies + * @nr_of_link_frequencies: number of elements in link_frequenccies array + */ +struct v4l2_fwnode_endpoint { + struct fwnode_endpoint base; + /* + * Fields below this line will be zeroed by + * v4l2_fwnode_parse_endpoint() + */ + enum v4l2_mbus_type bus_type; + union { + struct v4l2_fwnode_bus_parallel parallel; + struct v4l2_fwnode_bus_mipi_csi2 mipi_csi2; + } bus; + u64 *link_frequencies; + unsigned int nr_of_link_frequencies; +}; + +/** + * struct v4l2_fwnode_link - a link between two endpoints + * @local_node: pointer to device_node of this endpoint + * @local_port: identifier of the port this endpoint belongs to + * @remote_node: pointer to device_node of the remote endpoint + * @remote_port: identifier of the port the remote endpoint belongs to + */ +struct v4l2_fwnode_link { + struct fwnode_handle *local_node; + unsigned int local_port; + struct fwnode_handle *remote_node; + unsigned int remote_port; +}; + +int v4l2_fwnode_endpoint_parse(struct fwnode_handle *fwnode, + struct v4l2_fwnode_endpoint *vep); +struct v4l2_fwnode_endpoint *v4l2_fwnode_endpoint_alloc_parse( + struct fwnode_handle *fwnode); +void v4l2_fwnode_endpoint_free(struct v4l2_fwnode_endpoint *vep); +int v4l2_fwnode_parse_link(struct fwnode_handle *fwnode, + struct v4l2_fwnode_link *link); +void v4l2_fwnode_put_link(struct v4l2_fwnode_link *link); + +#endif /* _V4L2_FWNODE_H */ |