Hi Laurent, On Wed, Dec 02, 2020 at 12:30:53AM +0200, Laurent Pinchart wrote: > Hi Daniel, > > On Tue, Dec 01, 2020 at 10:08:25PM +0000, Dan Scally wrote: > > On 30/11/2020 17:09, Laurent Pinchart wrote: > > > On Mon, Nov 30, 2020 at 01:31:24PM +0000, Daniel Scally wrote: > > >> Currently on platforms designed for Windows, connections between CIO2 and > > >> sensors are not properly defined in DSDT. This patch extends the ipu3-cio2 > > >> driver to compensate by building software_node connections, parsing the > > >> connection properties from the sensor's SSDB buffer. > > >> > > >> Suggested-by: Jordan Hand <jorhand@xxxxxxxxxxxxxxxxxxx> > > >> Signed-off-by: Daniel Scally <djrscally@xxxxxxxxx> > > >> --- > > >> Changes since RFC v3: > > >> > > >> - Removed almost all global variables, dynamically allocated > > >> the cio2_bridge structure, plus a bunch of associated changes > > >> like > > >> - Added a new function to ipu3-cio2-main.c to check for an > > >> existing fwnode_graph before calling cio2_bridge_init() > > >> - Prefixed cio2_bridge_ to any variables and functions that > > >> lacked it > > >> - Assigned the new fwnode directly to the sensor's ACPI device > > >> fwnode as secondary. This removes the requirement to delay until > > >> the I2C devices are instantiated before ipu3-cio2 can probe, but > > >> it has a side effect, which is that those devices then grab a ref > > >> to the new software_node. This effectively prevents us from > > >> unloading the driver, because we can't free the memory that they > > >> live in whilst the device holds a reference to them. The work > > >> around at the moment is to _not_ unregister the software_nodes > > >> when ipu3-cio2 is unloaded; this becomes a one-time 'patch', that > > >> is simply skipped if the module is reloaded. > > >> - Moved the sensor's SSDB struct to be a member of cio2_sensor > > >> - Replaced ints with unsigned ints where appropriate > > >> - Iterated over all ACPI devices of a matching _HID rather than > > >> just the first to ensure we handle a device with multiple sensors > > >> of the same model. > > >> > > >> MAINTAINERS | 1 + > > >> drivers/media/pci/intel/ipu3/Kconfig | 18 ++ > > >> drivers/media/pci/intel/ipu3/Makefile | 1 + > > >> drivers/media/pci/intel/ipu3/cio2-bridge.c | 260 ++++++++++++++++++ > > >> drivers/media/pci/intel/ipu3/cio2-bridge.h | 108 ++++++++ > > >> drivers/media/pci/intel/ipu3/ipu3-cio2-main.c | 27 ++ > > >> drivers/media/pci/intel/ipu3/ipu3-cio2.h | 6 + > > >> 7 files changed, 421 insertions(+) > > >> create mode 100644 drivers/media/pci/intel/ipu3/cio2-bridge.c > > >> create mode 100644 drivers/media/pci/intel/ipu3/cio2-bridge.h > > >> > > >> diff --git a/MAINTAINERS b/MAINTAINERS > > >> index 9702b886d6a4..188559a0a610 100644 > > >> --- a/MAINTAINERS > > >> +++ b/MAINTAINERS > > >> @@ -8927,6 +8927,7 @@ INTEL IPU3 CSI-2 CIO2 DRIVER > > >> M: Yong Zhi <yong.zhi@xxxxxxxxx> > > >> M: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> > > >> M: Bingbu Cao <bingbu.cao@xxxxxxxxx> > > >> +M: Dan Scally <djrscally@xxxxxxxxx> > > >> R: Tianshu Qiu <tian.shu.qiu@xxxxxxxxx> > > >> L: linux-media@xxxxxxxxxxxxxxx > > >> S: Maintained > > >> diff --git a/drivers/media/pci/intel/ipu3/Kconfig b/drivers/media/pci/intel/ipu3/Kconfig > > >> index 82d7f17e6a02..2b3350d042be 100644 > > >> --- a/drivers/media/pci/intel/ipu3/Kconfig > > >> +++ b/drivers/media/pci/intel/ipu3/Kconfig > > >> @@ -16,3 +16,21 @@ config VIDEO_IPU3_CIO2 > > >> Say Y or M here if you have a Skylake/Kaby Lake SoC with MIPI CSI-2 > > >> connected camera. > > >> The module will be called ipu3-cio2. > > >> + > > >> +config CIO2_BRIDGE > > >> + bool "IPU3 CIO2 Sensors Bridge" > > >> + depends on VIDEO_IPU3_CIO2 > > >> + help > > >> + This extension provides an API for the ipu3-cio2 driver to create > > >> + connections to cameras that are hidden in SSDB buffer in ACPI. It > > >> + can be used to enable support for cameras in detachable / hybrid > > >> + devices that ship with Windows. > > >> + > > >> + Say Y here if your device is a detachable / hybrid laptop that comes > > >> + with Windows installed by the OEM, for example: > > >> + > > >> + - Microsoft Surface models (except Surface Pro 3) > > >> + - The Lenovo Miix line (for example the 510, 520, 710 and 720) > > >> + - Dell 7285 > > >> + > > >> + If in doubt, say N here. > > >> diff --git a/drivers/media/pci/intel/ipu3/Makefile b/drivers/media/pci/intel/ipu3/Makefile > > >> index 429d516452e4..933777e6ea8a 100644 > > >> --- a/drivers/media/pci/intel/ipu3/Makefile > > >> +++ b/drivers/media/pci/intel/ipu3/Makefile > > >> @@ -2,3 +2,4 @@ > > >> obj-$(CONFIG_VIDEO_IPU3_CIO2) += ipu3-cio2.o > > >> > > >> ipu3-cio2-y += ipu3-cio2-main.o > > >> +ipu3-cio2-$(CONFIG_CIO2_BRIDGE) += cio2-bridge.o > > >> diff --git a/drivers/media/pci/intel/ipu3/cio2-bridge.c b/drivers/media/pci/intel/ipu3/cio2-bridge.c > > >> new file mode 100644 > > >> index 000000000000..fd3f8ba07274 > > >> --- /dev/null > > >> +++ b/drivers/media/pci/intel/ipu3/cio2-bridge.c > > >> @@ -0,0 +1,260 @@ > > >> +// SPDX-License-Identifier: GPL-2.0 > > >> +/* Author: Dan Scally <djrscally@xxxxxxxxx> */ > > > > > > Could you please add a blank line here ? > > > > Yes > > > > >> +#include <linux/acpi.h> > > >> +#include <linux/device.h> > > >> +#include <linux/i2c.h> > > > > > > Is this header needed ? > > > > > >> +#include <linux/kernel.h> > > >> +#include <linux/module.h> > > > > > > And this one ? > > > > > >> +#include <linux/pci.h> > > >> +#include <linux/property.h> > > >> +#include <media/v4l2-subdev.h> > > > > > > And this one ? > > > > Ah yes - bit sloppy, they're orphaned from earlier versions, sorry about > > that. > > > > >> + > > >> +#include "cio2-bridge.h" > > >> + > > >> +/* > > >> + * Extend this array with ACPI Hardware ID's of devices known to be working. > > >> + * Do not add a HID for a sensor that is not actually supported. > > >> + */ > > >> +static const char * const cio2_supported_devices[] = { > > > > > > Maybe cio2_supported_sensors ? > > > > Sure > > > > >> + "INT33BE", > > >> + "OVTI2680", > > >> +}; > > >> + > > >> +static int cio2_bridge_read_acpi_buffer(struct acpi_device *adev, char *id, > > >> + void *data, u32 size) > > >> +{ > > >> + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; > > >> + union acpi_object *obj; > > >> + acpi_status status; > > >> + int ret; > > >> + > > >> + status = acpi_evaluate_object(adev->handle, id, NULL, &buffer); > > >> + if (ACPI_FAILURE(status)) > > >> + return -ENODEV; > > >> + > > >> + obj = buffer.pointer; > > >> + if (!obj) { > > >> + dev_err(&adev->dev, "Couldn't locate ACPI buffer\n"); > > >> + return -ENODEV; > > >> + } > > >> + > > >> + if (obj->type != ACPI_TYPE_BUFFER) { > > >> + dev_err(&adev->dev, "Not an ACPI buffer\n"); > > >> + ret = -ENODEV; > > >> + goto out_free_buff; > > >> + } > > >> + > > >> + if (obj->buffer.length > size) { > > >> + dev_err(&adev->dev, "Given buffer is too small\n"); > > >> + ret = -EINVAL; > > >> + goto out_free_buff; > > >> + } > > >> + > > >> + memcpy(data, obj->buffer.pointer, obj->buffer.length); > > >> + ret = obj->buffer.length; > > >> + > > >> +out_free_buff: > > >> + kfree(buffer.pointer); > > >> + return ret; > > >> +} > > >> + > > >> +static void cio2_bridge_init_property_names(struct cio2_sensor *sensor) > > >> +{ > > >> + strcpy(sensor->prop_names.clock_frequency, "clock-frequency"); > > >> + strcpy(sensor->prop_names.rotation, "rotation"); > > >> + strcpy(sensor->prop_names.bus_type, "bus-type"); > > >> + strcpy(sensor->prop_names.data_lanes, "data-lanes"); > > >> + strcpy(sensor->prop_names.remote_endpoint, "remote-endpoint"); > > > > > > This is a bit fragile, as there's no len check. How about the following > > > ? > > > static const struct cio2_property_names prop_names = { > > > .clock_frequency = "clock-frequency", > > > .rotation = "rotation", > > > .bus_type = "bus-type", > > > .data_lanes = "data-lanes", > > > .remote_endpoint = "remote-endpoint", > > > }; > > > > > > static void cio2_bridge_init_property_names(struct cio2_sensor *sensor) > > > { > > > sensor->prop_names = prop_names; > > > } > > > > > > This shoudl generate a compilation warning if the string is too long. > > > > > > You could even inline that line in > > > cio2_bridge_create_fwnode_properties(). > > > > Yes, I like that, thanks - I'll make the change. > > > > >> +} > > >> + > > >> +static void cio2_bridge_create_fwnode_properties(struct cio2_sensor *sensor) > > >> +{ > > >> + unsigned int i; > > >> + > > >> + cio2_bridge_init_property_names(sensor); > > >> + > > >> + for (i = 0; i < 4; i++) > > >> + sensor->data_lanes[i] = i + 1; > > > > > > Is there no provision in the SSDB for data lane remapping ? > > > > Sorry; don't follow what you mean by data lane remapping here. > > Some CSI-2 receivers can remap data lanes. The routing inside the SoC > from the data lane input pins to the PHYs is configurable. This makes > board design easier as you can route the data lanes to any of the > inputs. That's why the data lanes DT property is a list of lane numbers > instead of a number of lanes. I'm actually not sure if the CIO2 supports > this. To my knowledge it does not. Only the number of lanes allocated to different ports matters. ... > > >> @@ -0,0 +1,108 @@ > > >> +/* SPDX-License-Identifier: GPL-2.0 */ > > >> +/* Author: Dan Scally <djrscally@xxxxxxxxx> */ > > >> +#ifndef __CIO2_BRIDGE_H > > >> +#define __CIO2_BRIDGE_H > > >> + > > >> +#include <linux/property.h> > > >> + > > >> +#define CIO2_HID "INT343E" > > >> +#define CIO2_NUM_PORTS 4 > > > > > > There are a few rogue spaces before '4'. > > > > Argh, thanks, this is the curse of using VS code on multiple machines... > > I recommend vim ;-) What is VS code? Very Serious Code? I can recommend Emacs; that could help, too. -- Kind regards, Sakari Ailus