Re: [PATCH v3 14/14] ipu3-cio2: Add cio2-bridge to ipu3-cio2 driver

[Sakari Ailus <sakari.ailus@linux.intel.com>]

Hi Andy, Daniel,

On Thu, Dec 24, 2020 at 02:54:44PM +0200, Andy Shevchenko wrote:
> On Thu, Dec 24, 2020 at 3:12 AM Daniel Scally <djrscally@gmail.com> 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.
> 
> Few nitpicks below, after addressing them
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> 
> > Suggested-by: Jordan Hand <jorhand@linux.microsoft.com>
> > Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> > Signed-off-by: Daniel Scally <djrscally@gmail.com>
> > ---
> > Changes in v3
> >         - Used Laurent's suggestion to simplify initing the property names
> >         - Wrapped some lines
> >         - Fixed return and error handling for cio2_bridge_read_acpi_buffer()
> >         - Returned an error if more sensors than available ports are detected
> >         - Used defines for port/endpoint name formats and the bus-type property
> >         - Some bits of cleanup
> >
> >  MAINTAINERS                                   |   1 +
> >  drivers/media/pci/intel/ipu3/Kconfig          |  18 ++
> >  drivers/media/pci/intel/ipu3/Makefile         |   1 +
> >  drivers/media/pci/intel/ipu3/cio2-bridge.c    | 272 ++++++++++++++++++
> >  drivers/media/pci/intel/ipu3/cio2-bridge.h    | 122 ++++++++
> >  drivers/media/pci/intel/ipu3/ipu3-cio2-main.c |  34 +++
> >  drivers/media/pci/intel/ipu3/ipu3-cio2.h      |   6 +
> >  7 files changed, 454 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 16b544624577..e7784b4bc8ea 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -8943,6 +8943,7 @@ INTEL IPU3 CSI-2 CIO2 DRIVER
> >  M:     Yong Zhi <yong.zhi@intel.com>
> >  M:     Sakari Ailus <sakari.ailus@linux.intel.com>
> >  M:     Bingbu Cao <bingbu.cao@intel.com>
> > +M:     Dan Scally <djrscally@gmail.com>
> >  R:     Tianshu Qiu <tian.shu.qiu@intel.com>
> >  L:     linux-media@vger.kernel.org
> >  S:     Maintained
> > diff --git a/drivers/media/pci/intel/ipu3/Kconfig b/drivers/media/pci/intel/ipu3/Kconfig
> > index 82d7f17e6a02..dcf5c4b74673 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
> 
> in the
> 
> > +         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..3f4ae172fd25
> > --- /dev/null
> > +++ b/drivers/media/pci/intel/ipu3/cio2-bridge.c
> > @@ -0,0 +1,272 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/* Author: Dan Scally <djrscally@gmail.com> */
> > +
> > +#include <linux/acpi.h>
> > +#include <linux/device.h>
> > +#include <linux/pci.h>
> > +#include <linux/property.h>
> > +#include <media/v4l2-fwnode.h>
> > +
> > +#include "cio2-bridge.h"
> > +
> > +/*
> > + * Extend this array with ACPI Hardware ID's of devices known to be working
> 
> ID's -> IDs ?
> 
> > + * plus the number of link-frequencies expected by their drivers, along with
> > + * the frequency values in hertz. This is somewhat opportunistic way of adding
> > + * support for this for now in the hopes of a better source for the information
> > + * (possibly some encoded value in the SSDB buffer that we're unaware of)
> > + * becoming apparent in the future.
> > + *
> > + * Do not add an entry for a sensor that is not actually supported.
> > + */
> > +static const struct cio2_sensor_config cio2_supported_sensors[] = {
> > +       CIO2_SENSOR_CONFIG("INT33BE", 0),
> > +       CIO2_SENSOR_CONFIG("OVTI2680", 0),
> > +};
> > +
> > +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",
> > +       .link_frequencies = "link-frequencies",
> > +};
> > +
> > +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 = 0;
> > +
> > +       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);
> > +
> > +out_free_buff:
> > +       kfree(buffer.pointer);
> > +       return ret;
> > +}
> > +
> > +static void cio2_bridge_create_fwnode_properties(struct cio2_sensor *sensor,
> > +                                                const struct cio2_sensor_config *cfg)
> > +{
> > +       unsigned int i;
> > +
> > +       sensor->prop_names = prop_names;
> > +
> > +       for (i = 0; i < 4; i++)
> 
> 4 here and below, can we have a local define for them, like
> 
>   #define CIO2_MAX_LANES  4
> 
> > +               sensor->data_lanes[i] = i + 1;
> > +
> > +       sensor->local_ref[0].node = &sensor->swnodes[SWNODE_CIO2_ENDPOINT];
> > +       sensor->remote_ref[0].node = &sensor->swnodes[SWNODE_SENSOR_ENDPOINT];
> > +
> > +       sensor->dev_properties[0] = PROPERTY_ENTRY_U32(sensor->prop_names.clock_frequency,
> > +                                                      sensor->ssdb.mclkspeed);
> > +       sensor->dev_properties[1] = PROPERTY_ENTRY_U8(sensor->prop_names.rotation,
> > +                                                     sensor->ssdb.degree);
> > +
> > +       sensor->ep_properties[0] = PROPERTY_ENTRY_U32(sensor->prop_names.bus_type,
> > +                                                     V4L2_FWNODE_BUS_TYPE_CSI2_DPHY);
> > +       sensor->ep_properties[1] = PROPERTY_ENTRY_U32_ARRAY_LEN(sensor->prop_names.data_lanes,
> > +                                                               sensor->data_lanes,
> > +                                                               sensor->ssdb.lanes);
> > +       sensor->ep_properties[2] = PROPERTY_ENTRY_REF_ARRAY(sensor->prop_names.remote_endpoint,
> > +                                                           sensor->local_ref);
> > +
> > +       if (cfg->nr_link_freqs > 0)
> > +               sensor->ep_properties[3] = PROPERTY_ENTRY_U64_ARRAY_LEN(
> > +                                               sensor->prop_names.link_frequencies,
> > +                                               cfg->link_freqs,
> > +                                               cfg->nr_link_freqs);
> > +
> > +       sensor->cio2_properties[0] = PROPERTY_ENTRY_U32_ARRAY_LEN(sensor->prop_names.data_lanes,
> > +                                                                 sensor->data_lanes,
> > +                                                                 sensor->ssdb.lanes);
> > +       sensor->cio2_properties[1] = PROPERTY_ENTRY_REF_ARRAY(sensor->prop_names.remote_endpoint,
> > +                                                             sensor->remote_ref);
> > +}
> > +
> > +static void cio2_bridge_init_swnode_names(struct cio2_sensor *sensor)
> > +{
> > +       snprintf(sensor->node_names.remote_port, sizeof(sensor->node_names.remote_port),
> > +                FWNODE_GRAPH_PORT_NAME_FORMAT, sensor->ssdb.link);
> > +       snprintf(sensor->node_names.port, sizeof(sensor->node_names.port),
> > +                FWNODE_GRAPH_PORT_NAME_FORMAT, 0); /* Always port 0 */
> > +       snprintf(sensor->node_names.endpoint, sizeof(sensor->node_names.endpoint),
> > +                FWNODE_GRAPH_ENDPOINT_NAME_FORMAT, 0); /* And endpoint 0 */

Please wrap before 80, there's no need here to do otherwise. You could
argue about cio2_bridge_create_fwnode_properties() though. I might just
wrap that, too.

Applies to the rest of the patch.

> > +}
> > +
> > +static void cio2_bridge_create_connection_swnodes(struct cio2_bridge *bridge,
> > +                                                 struct cio2_sensor *sensor)
> > +{
> > +       struct software_node *nodes = sensor->swnodes;
> > +
> > +       cio2_bridge_init_swnode_names(sensor);
> > +
> > +       nodes[SWNODE_SENSOR_HID] = NODE_SENSOR(sensor->name,
> > +                                              sensor->dev_properties);
> > +       nodes[SWNODE_SENSOR_PORT] = NODE_PORT(sensor->node_names.port,
> > +                                             &nodes[SWNODE_SENSOR_HID]);
> > +       nodes[SWNODE_SENSOR_ENDPOINT] = NODE_ENDPOINT(sensor->node_names.endpoint,
> > +                                                     &nodes[SWNODE_SENSOR_PORT],
> > +                                                     sensor->ep_properties);
> > +       nodes[SWNODE_CIO2_PORT] = NODE_PORT(sensor->node_names.remote_port,
> > +                                           &bridge->cio2_hid_node);
> > +       nodes[SWNODE_CIO2_ENDPOINT] = NODE_ENDPOINT(sensor->node_names.endpoint,
> > +                                                   &nodes[SWNODE_CIO2_PORT],
> > +                                                   sensor->cio2_properties);
> > +}
> > +
> > +static void cio2_bridge_unregister_sensors(struct cio2_bridge *bridge)
> > +{
> > +       struct cio2_sensor *sensor;
> > +       unsigned int i;
> > +
> > +       for (i = 0; i < bridge->n_sensors; i++) {
> > +               sensor = &bridge->sensors[i];
> > +               software_node_unregister_nodes(sensor->swnodes);
> > +               acpi_dev_put(sensor->adev);
> > +       }
> > +}
> > +
> > +static int cio2_bridge_connect_sensors(struct cio2_bridge *bridge,
> > +                                      struct pci_dev *cio2)
> > +{
> > +       struct fwnode_handle *fwnode;
> > +       struct cio2_sensor *sensor;
> > +       struct acpi_device *adev;
> > +       unsigned int i;
> > +       int ret = 0;
> 
> You may drop this assignment and...
> 
> > +       for (i = 0; i < ARRAY_SIZE(cio2_supported_sensors); i++) {
> > +               const struct cio2_sensor_config *cfg = &cio2_supported_sensors[i];

You could move the inner loop into a new function called e.g.
cio2_bridge_connect_sensor.

> > +
> > +               for_each_acpi_dev_match(adev, cfg->hid, NULL, -1) {
> > +                       if (bridge->n_sensors >= CIO2_NUM_PORTS) {
> > +                               dev_err(&cio2->dev, "Exceeded available CIO2 ports\n");
> > +                               cio2_bridge_unregister_sensors(bridge);
> > +                               ret = -EINVAL;
> > +                               goto err_out;
> > +                       }
> > +
> > +                       if (!adev->status.enabled)
> > +                               continue;
> > +
> > +                       sensor = &bridge->sensors[bridge->n_sensors];
> > +                       sensor->adev = adev;
> > +                       strscpy(sensor->name, cfg->hid, sizeof(sensor->name));
> > +
> > +                       ret = cio2_bridge_read_acpi_buffer(adev, "SSDB",
> > +                                                          &sensor->ssdb,
> > +                                                          sizeof(sensor->ssdb));
> > +                       if (ret)
> > +                               goto err_put_adev;
> > +
> > +                       if (sensor->ssdb.lanes > 4) {
> 
> CIO2_MAX_LANES
> 
> > +                               dev_err(&adev->dev,
> > +                                       "Number of lanes in SSDB is invalid\n");
> > +                               ret = -EINVAL;
> > +                               goto err_put_adev;
> > +                       }
> > +
> > +                       cio2_bridge_create_fwnode_properties(sensor, cfg);
> > +                       cio2_bridge_create_connection_swnodes(bridge, sensor);
> > +
> > +                       ret = software_node_register_nodes(sensor->swnodes);
> > +                       if (ret)
> > +                               goto err_put_adev;
> > +
> > +                       fwnode = software_node_fwnode(&sensor->swnodes[SWNODE_SENSOR_HID]);
> > +                       if (!fwnode) {
> > +                               ret = -ENODEV;
> > +                               goto err_free_swnodes;
> > +                       }
> > +
> > +                       adev->fwnode.secondary = fwnode;
> > +
> > +                       dev_info(&cio2->dev, "Found supported sensor %s\n",
> > +                                acpi_dev_name(adev));
> > +
> > +                       bridge->n_sensors++;
> > +               }
> > +       }
> 
> > +       return ret;
> 
> ...use here
> 
>   return 0;
> 
> directly.
> 
> > +err_free_swnodes:
> > +       software_node_unregister_nodes(sensor->swnodes);
> > +err_put_adev:
> > +       acpi_dev_put(sensor->adev);
> > +err_out:
> > +       return ret;
> > +}
> > +
> > +int cio2_bridge_init(struct pci_dev *cio2)
> > +{
> > +       struct device *dev = &cio2->dev;
> > +       struct fwnode_handle *fwnode;
> > +       struct cio2_bridge *bridge;
> > +       int ret;
> > +
> > +       bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
> > +       if (!bridge)
> > +               return -ENOMEM;
> > +
> > +       strscpy(bridge->cio2_node_name, CIO2_HID, sizeof(bridge->cio2_node_name));
> > +       bridge->cio2_hid_node.name = bridge->cio2_node_name;
> > +
> > +       ret = software_node_register(&bridge->cio2_hid_node);
> > +       if (ret < 0) {
> > +               dev_err(dev, "Failed to register the CIO2 HID node\n");
> > +               goto err_free_bridge;
> > +       }
> > +
> > +       ret = cio2_bridge_connect_sensors(bridge, cio2);
> > +       if (ret || bridge->n_sensors == 0)
> > +               goto err_unregister_cio2;
> > +
> > +       dev_info(dev, "Connected %d cameras\n", bridge->n_sensors);
> > +
> > +       fwnode = software_node_fwnode(&bridge->cio2_hid_node);
> > +       if (!fwnode) {
> > +               dev_err(dev, "Error getting fwnode from cio2 software_node\n");
> > +               ret = -ENODEV;
> > +               goto err_unregister_sensors;
> > +       }
> > +
> > +       set_secondary_fwnode(dev, fwnode);
> > +
> > +       return 0;
> > +
> > +err_unregister_sensors:
> > +       cio2_bridge_unregister_sensors(bridge);
> > +err_unregister_cio2:
> > +       software_node_unregister(&bridge->cio2_hid_node);
> > +err_free_bridge:
> > +       kfree(bridge);
> > +
> > +       return ret;
> > +}
> > diff --git a/drivers/media/pci/intel/ipu3/cio2-bridge.h b/drivers/media/pci/intel/ipu3/cio2-bridge.h
> > new file mode 100644
> > index 000000000000..004b608f322f
> > --- /dev/null
> > +++ b/drivers/media/pci/intel/ipu3/cio2-bridge.h
> > @@ -0,0 +1,122 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/* Author: Dan Scally <djrscally@gmail.com> */
> > +#ifndef __CIO2_BRIDGE_H
> > +#define __CIO2_BRIDGE_H
> > +
> > +#include <linux/property.h>
> > +
> > +#define CIO2_HID                               "INT343E"
> > +#define CIO2_NUM_PORTS                         4

This is already defined in ipu3-cio2.h. Could you include that instead?

> > +#define MAX_NUM_LINK_FREQS                     3
> > +
> > +#define CIO2_SENSOR_CONFIG(_HID, _NR, ...)     \
> > +       {                                       \
> > +               .hid = _HID,                    \
> > +               .nr_link_freqs = _NR,           \
> > +               .link_freqs = { __VA_ARGS__ }   \
> > +       }
> > +
> > +#define NODE_SENSOR(_HID, _PROPS)              \
> > +       ((const struct software_node) {         \
> > +               .name = _HID,                   \
> > +               .properties = _PROPS,           \
> > +       })
> > +
> > +#define NODE_PORT(_PORT, _SENSOR_NODE)         \
> > +       ((const struct software_node) {         \
> > +               _PORT,                          \
> > +               _SENSOR_NODE,                   \

Could you use explicit assignments to fields here, please?

> > +       })
> > +
> > +#define NODE_ENDPOINT(_EP, _PORT, _PROPS)      \
> > +       ((const struct software_node) {         \
> > +               _EP,                            \
> > +               _PORT,                          \
> > +               _PROPS,                         \

Ditto.

> > +       })
> > +
> > +enum cio2_sensor_swnodes {
> > +       SWNODE_SENSOR_HID,
> > +       SWNODE_SENSOR_PORT,
> > +       SWNODE_SENSOR_ENDPOINT,
> > +       SWNODE_CIO2_PORT,
> > +       SWNODE_CIO2_ENDPOINT,
> 
> > +       SWNODE_COUNT,
> 
> No comma?
> 
> > +};
> > +
> > +/* Data representation as it is in ACPI SSDB buffer */
> > +struct cio2_sensor_ssdb {
> > +       u8 version;
> > +       u8 sku;
> > +       u8 guid_csi2[16];
> > +       u8 devfunction;
> > +       u8 bus;
> > +       u32 dphylinkenfuses;
> > +       u32 clockdiv;
> > +       u8 link;
> > +       u8 lanes;
> > +       u32 csiparams[10];
> > +       u32 maxlanespeed;
> > +       u8 sensorcalibfileidx;
> > +       u8 sensorcalibfileidxInMBZ[3];
> > +       u8 romtype;
> > +       u8 vcmtype;
> > +       u8 platforminfo;
> > +       u8 platformsubinfo;
> > +       u8 flash;
> > +       u8 privacyled;
> > +       u8 degree;
> > +       u8 mipilinkdefined;
> > +       u32 mclkspeed;
> > +       u8 controllogicid;
> > +       u8 reserved1[3];
> > +       u8 mclkport;
> > +       u8 reserved2[13];
> > +} __packed;
> > +
> > +struct cio2_property_names {
> > +       char clock_frequency[16];
> > +       char rotation[9];
> > +       char bus_type[9];
> > +       char data_lanes[11];
> > +       char remote_endpoint[16];
> > +       char link_frequencies[17];
> > +};
> > +
> > +struct cio2_node_names {
> > +       char port[7];
> > +       char endpoint[11];
> > +       char remote_port[7];
> > +};
> > +
> > +struct cio2_sensor_config {
> > +       const char *hid;
> > +       const u8 nr_link_freqs;
> > +       const u64 link_freqs[MAX_NUM_LINK_FREQS];
> > +};
> > +
> > +struct cio2_sensor {
> > +       char name[ACPI_ID_LEN];
> > +       struct acpi_device *adev;
> > +
> > +       struct software_node swnodes[6];
> > +       struct cio2_node_names node_names;
> > +
> > +       u32 data_lanes[4];
> > +       struct cio2_sensor_ssdb ssdb;
> > +       struct cio2_property_names prop_names;
> > +       struct property_entry ep_properties[5];
> > +       struct property_entry dev_properties[3];
> > +       struct property_entry cio2_properties[3];
> > +       struct software_node_ref_args local_ref[1];
> > +       struct software_node_ref_args remote_ref[1];
> > +};
> > +
> > +struct cio2_bridge {
> > +       char cio2_node_name[ACPI_ID_LEN];
> > +       struct software_node cio2_hid_node;
> > +       unsigned int n_sensors;
> > +       struct cio2_sensor sensors[CIO2_NUM_PORTS];
> > +};
> > +
> > +#endif
> > diff --git a/drivers/media/pci/intel/ipu3/ipu3-cio2-main.c b/drivers/media/pci/intel/ipu3/ipu3-cio2-main.c
> > index 36e354ecf71e..68ff28abc6a3 100644
> > --- a/drivers/media/pci/intel/ipu3/ipu3-cio2-main.c
> > +++ b/drivers/media/pci/intel/ipu3/ipu3-cio2-main.c
> > @@ -1702,11 +1702,28 @@ static void cio2_queues_exit(struct cio2_device *cio2)
> >                 cio2_queue_exit(cio2, &cio2->queue[i]);
> >  }
> >
> > +static bool cio2_check_fwnode_graph(struct fwnode_handle *fwnode)
> > +{
> > +       struct fwnode_handle *endpoint;
> > +
> > +       if (IS_ERR_OR_NULL(fwnode))
> > +               return false;
> > +
> > +       endpoint = fwnode_graph_get_next_endpoint(fwnode, NULL);
> > +       if (endpoint) {
> > +               fwnode_handle_put(endpoint);
> > +               return true;
> > +       }
> > +
> > +       return cio2_check_fwnode_graph(fwnode->secondary);
> > +}
> > +
> >  /**************** PCI interface ****************/
> >
> >  static int cio2_pci_probe(struct pci_dev *pci_dev,
> >                           const struct pci_device_id *id)
> >  {
> > +       struct fwnode_handle *fwnode = dev_fwnode(&pci_dev->dev);
> >         struct cio2_device *cio2;
> >         int r;
> >
> > @@ -1715,6 +1732,23 @@ static int cio2_pci_probe(struct pci_dev *pci_dev,
> >                 return -ENOMEM;
> >         cio2->pci_dev = pci_dev;
> >
> > +       /*
> > +        * On some platforms no connections to sensors are defined in firmware,
> > +        * if the device has no endpoints then we can try to build those as
> > +        * software_nodes parsed from SSDB.
> > +        */
> > +       if (!cio2_check_fwnode_graph(fwnode)) {
> > +               if (fwnode && !IS_ERR_OR_NULL(fwnode->secondary)) {
> 
> > +                       dev_err(&pci_dev->dev,
> > +                               "fwnode graph has no endpoints connected\n");
> 
> One line?

Hmm. That'll be over 80 anyway, but now it's less so.

-- 
Kind regards,

Sakari Ailus