[PATCH v4 0/8] ACPI _CRS CSI-2 and MIPI DisCo for Imaging support

Sakari Ailus
2023-02-08T15:28:58Z

Hello all,

Here's an implementation of ACPI 6.4 _CRS CSI-2 resource descriptor and
MIPI DisCo for Imaging 1.0 [1]. What the two basically provide is an
officially sanctioned way to describe CSI-2 connected cameras to operating
system software, something DT based systems have enjoyed for quite some
time already.

The implementation digs the information from ACPI tables (_CRS descriptors
and data + property extensions) and constructs software nodes that are
compatible with Documentation/firmware-guide/acpi/dsd/graph.rst and
Documentation/devicetree/bindings/media/video-interface-devices.yaml . No
specific driver changes are needed.

These patches are on the testing branch of the linux-acpi tree where they
depend on the patch constifying the ACPI pathname argument for
acpi_get_handle() (commit 91fdb91ccca2b48572a1ccf1d382fd599e3e1237).

[1] https://www.mipi.org/specifications/mipi-disco-imaging

since v3:

- Add comments to data structures and functions, code inside functions.

- Use ACPI_FAILURE() for testing ACPI framework function return values.

- Unwrap a few lines.

- Rename list heads as "head", some were called just "list".

- Count ACPI handles related to _CRS CSI2 resources during tree walk.

- Reshape testing for CSI-2 port allocation in next_csi2_port_index().

- Move allocation of software nodes into a new function,
acpi_crs_csi2_alloc_fill_swnodes().

- Comments: acpi_bus_scan_crs_csi2() is to be called on the namespace
root.

- Use size_t for this_count variable in acpi_bus_scan_crs_csi2().

- Revert the NEXT_PROPERTY() macro condition to original (the suggested
one was different).

- Remove u union in init_port_csi2_common().

- Fix val array size in init_port_csi2_common(). This issue was masked by
the presence of a u32 field in the union.

- Use "-" for copyright year range.

since v2:

- Unwrap a few lines.

- Copy CSI-2 resource source string using strscpy() instead of memcpy() in
scan_check_crs_csi2_instance.

- Fix GRAPH_PORT_NAME() sanity check bug introduced in v2.

- Fix snprintf() return value check for port node name in
get_mipi_port_handle().

- Fix mipi-img-lane-polarities reading.

- Cast bit value to bool instead of using ... ? 1U : 0U.

- Get primary fwnode using acpi_fwnode_handle().

- Don't use MIPI_IMG_PREFIX in the array of renamed properties.

- Use tabs for indenting drivers/acpi/property.c authors.

- Add a comment on assigning ACPI device's secondary fwnode and assign
ACPI device's secondary fwnode straight to NULL when unassigning it.

since v1:

- Update copyright notices.

- Include linux/types.h instead of linux/kernel.h in drivers/acpi/mipi.c.

- Use SWNODE_GRAPH_PORT_NAME_FMT instead of plain "port@%u" in
GRAPH_PORT_NAME macro.

- Make the condition in NEXT_PROPERTY() macro easier to read.

- Unwrap lines to make them moderately longer than 80 characters.

- Use * BITS_PER_TYPE(u8) instead of << 3 to convert bytes to bits in
init_port_csi2_common().

- Test ACPI framework call success using ACPI_SUCCESS() instead of
comparing with AE_OK. Likewise for ACPI_FAILURE and != AE_OK.

- Use newly added SOFTWARE_NODE() macro to construct the root software
node.

- Use str_has_prefix() to test for a string prefix instead of memcmp().

- Add pr_fmt() macro to drivers/acpi/property.c.

- Move logical or operators to the end of the line in
acpi_properties_prepare().

- Improve bad node type error in acpi_parse_string_ref().

Sakari Ailus (8):
ACPI: property: Parse data node string references in properties
ACPI: property: Parse _CRS CSI-2 descriptor
device property: Add SOFTWARE_NODE() macro for defining software nodes
ACPI: property: Generate camera swnodes for ACPI and DisCo for Imaging
ACPI: property: Dig "rotation" property for devices with CSI2 _CRS
ACPI: property: Rename parsed MIPI DisCo for Imaging properties
ACPI: property: Skip MIPI property table without "mipi-img" prefix
ACPI: property: Document _CRS CSI-2 and DisCo for Imaging support

drivers/acpi/Makefile | 2 +-
drivers/acpi/internal.h | 9 +
drivers/acpi/mipi.c | 806 +++++++++++++++++++++++++++++++++++++++
drivers/acpi/property.c | 132 +++++--
drivers/acpi/scan.c | 35 +-
include/acpi/acpi_bus.h | 82 ++++
include/linux/property.h | 7 +
7 files changed, 1042 insertions(+), 31 deletions(-)
create mode 100644 drivers/acpi/mipi.c

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2.30.2