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

From: Sakari Ailus
Date: Mon Dec 28 2020 - 12:07:39 EST


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@xxxxxxxxx> 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@xxxxxxxxx>
>
> > Suggested-by: Jordan Hand <jorhand@xxxxxxxxxxxxxxxxxxx>
> > Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> > Signed-off-by: Daniel Scally <djrscally@xxxxxxxxx>
> > ---
> > 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@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..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@xxxxxxxxx> */
> > +
> > +#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@xxxxxxxxx> */
> > +#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