Hi Daniel, Thank you for the patch. On Mon, Oct 19, 2020 at 11:59:03PM +0100, 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 in v3: > - Rather than overwriting the device's primary fwnode, we now > simply assign a secondary. Some of the preceding patches alter the > existing driver code and v4l2 framework to allow for that. > - Rather than reprobe() the sensor after connecting the devices in > cio2-bridge we create the software_nodes right away. In this case, > sensor drivers will have to defer probing until they detect that a > fwnode graph is connecting them to the CIO2 device. > - Error paths in connect_supported_devices() moved outside the > loop > - Replaced pr_*() with dev_*() throughout > - Moved creation of software_node / property_entry arrays to stack > - A lot of formatting changes. > > MAINTAINERS | 1 + > drivers/media/pci/intel/ipu3/Kconfig | 18 + > drivers/media/pci/intel/ipu3/Makefile | 3 +- > drivers/media/pci/intel/ipu3/cio2-bridge.c | 327 ++++++++++++++++++ > drivers/media/pci/intel/ipu3/cio2-bridge.h | 94 +++++ > drivers/media/pci/intel/ipu3/ipu3-cio2-main.c | 21 ++ > drivers/media/pci/intel/ipu3/ipu3-cio2.h | 9 + > 7 files changed, 472 insertions(+), 1 deletion(-) > 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 5d768d5ad..4c9c646c7 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -8848,6 +8848,7 @@ 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 82d7f17e6..d14cbceae 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: > + > + - Some Microsoft Surface models > + - The Lenovo Miix line > + - 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 b4e3266d9..933777e6e 100644 > --- a/drivers/media/pci/intel/ipu3/Makefile > +++ b/drivers/media/pci/intel/ipu3/Makefile > @@ -1,4 +1,5 @@ > # SPDX-License-Identifier: GPL-2.0-only > obj-$(CONFIG_VIDEO_IPU3_CIO2) += ipu3-cio2.o > > -ipu3-cio2-y += ipu3-cio2-main.o > \ No newline at end of file > +ipu3-cio2-y += ipu3-cio2-main.o > +ipu3-cio2-$(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 000000000..bbe072f04 > --- /dev/null > +++ b/drivers/media/pci/intel/ipu3/cio2-bridge.c > @@ -0,0 +1,327 @@ > +// SPDX-License-Identifier: GPL-2.0 > +// Author: Dan Scally <djrscally@xxxxxxxxx> > +#include <linux/acpi.h> > +#include <linux/device.h> > +#include <linux/fwnode.h> > +#include <linux/i2c.h> > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/pci.h> > +#include <linux/property.h> > +#include <media/v4l2-subdev.h> > + > +#include "cio2-bridge.h" > + > +/* > + * Extend this array with ACPI Hardware ID's of devices known to be > + * working > + */ > +static const char * const supported_devices[] = { > + "INT33BE", > + "OVTI2680", > +}; > + > +static struct software_node cio2_hid_node = { CIO2_HID }; > + > +static struct cio2_bridge bridge; While there shouldn't be more than one CIO2 instance, we try to develop drivers in a way that avoids global per-device variables. Could all this be allocated dynamically, with the pointer returned by cio2_bridge_build() and stored in the cio2_device structure ? > + > +static const char * const port_names[] = { > + "port0", "port1", "port2", "port3" > +}; > + > +static const struct property_entry remote_endpoints[] = { > + PROPERTY_ENTRY_REF("remote-endpoint", /* Sensor 0, Sensor Property */ > + &bridge.sensors[0].swnodes[SWNODE_CIO2_ENDPOINT]), > + PROPERTY_ENTRY_REF("remote-endpoint", /* Sensor 0, CIO2 Property */ > + &bridge.sensors[0].swnodes[SWNODE_SENSOR_ENDPOINT]), > + PROPERTY_ENTRY_REF("remote-endpoint", > + &bridge.sensors[1].swnodes[SWNODE_CIO2_ENDPOINT]), > + PROPERTY_ENTRY_REF("remote-endpoint", > + &bridge.sensors[1].swnodes[SWNODE_SENSOR_ENDPOINT]), > + PROPERTY_ENTRY_REF("remote-endpoint", > + &bridge.sensors[2].swnodes[SWNODE_CIO2_ENDPOINT]), > + PROPERTY_ENTRY_REF("remote-endpoint", > + &bridge.sensors[2].swnodes[SWNODE_SENSOR_ENDPOINT]), > + PROPERTY_ENTRY_REF("remote-endpoint", > + &bridge.sensors[3].swnodes[SWNODE_CIO2_ENDPOINT]), > + PROPERTY_ENTRY_REF("remote-endpoint", > + &bridge.sensors[3].swnodes[SWNODE_SENSOR_ENDPOINT]), > +}; For the same reason, I would move this to the sensor structure (with two property_entry per sensor). That will simplify the code below, avoiding indexing this array with bridge.n_sensors * 2. > + > +static int read_acpi_block(struct device *dev, char *id, void *data, u32 size) To avoid potential future namespace classes, I'd advise naming the functions with a cio2_bridge_ prefix, even the static ones. And maybe cio2_bridge_read_acpi_buffer(), as this function reads a buffer ? > +{ > + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; > + struct acpi_handle *handle; > + union acpi_object *obj; > + acpi_status status; > + int ret; > + > + handle = ACPI_HANDLE(dev); > + > + status = acpi_evaluate_object(handle, id, NULL, &buffer); > + if (ACPI_FAILURE(status)) > + return -ENODEV; > + > + obj = buffer.pointer; > + if (!obj) { > + dev_err(dev, "Couldn't locate ACPI buffer\n"); > + return -ENODEV; > + } > + > + if (obj->type != ACPI_TYPE_BUFFER) { > + dev_err(dev, "Couldn't read ACPI buffer\n"); > + ret = -ENODEV; > + goto out_free_buff; > + } > + > + if (obj->buffer.length > size) { > + dev_err(dev, "Given buffer is too small\n"); > + ret = -ENODEV; > + 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 int get_acpi_ssdb_sensor_data(struct device *dev, > + struct sensor_bios_data *sensor) > +{ > + struct sensor_bios_data_packed sensor_data; > + int ret; > + > + ret = read_acpi_block(dev, "SSDB", &sensor_data, sizeof(sensor_data)); > + if (ret < 0) > + return ret; > + > + sensor->link = sensor_data.link; > + sensor->lanes = sensor_data.lanes; > + sensor->mclkspeed = sensor_data.mclkspeed; > + sensor->degree = sensor_data.degree; How about storing a sensor_bios_data_packed inside sensor_bios_data ? That will avoid copying fields individually, with manual addition of extra fields as they become useful. Usage of the sensor_bios_data structure would turn from sensor->degree to sensor->ssdb.degree, which is slightly longer, but I think more maintainable. > + > + return 0; > +} > + > +static int create_fwnode_properties(struct sensor *sensor, > + struct sensor_bios_data *ssdb) > +{ > + struct property_entry *cio2_properties = sensor->cio2_properties; > + struct property_entry *dev_properties = sensor->dev_properties; > + struct property_entry *ep_properties = sensor->ep_properties; > + int i; i never takes negative values, you can make it an unsigned int. Same for other occurrences below. > + > + /* device fwnode properties */ > + memset(dev_properties, 0, sizeof(struct property_entry) * 3); I would memset() bridge to 0 in one go and avoid individual memsets. And if you allocate it with kzalloc() it will be initialized to 0. > + > + dev_properties[0] = PROPERTY_ENTRY_U32("clock-frequency", > + ssdb->mclkspeed); > + dev_properties[1] = PROPERTY_ENTRY_U8("rotation", ssdb->degree); > + > + /* endpoint fwnode properties */ > + memset(ep_properties, 0, sizeof(struct property_entry) * 4); > + > + sensor->data_lanes = kmalloc_array(ssdb->lanes, sizeof(u32), > + GFP_KERNEL); Given that there can't be more than 4 data lanes, how about turning data_lanes into an array with 4 entries, to avoid the dynamic allocation ? You will have to validate ssdb->lanes in connect_supported_devices(), to make sure not to overflow the array. This and the next function can then be turned into void functions. > + > + if (!sensor->data_lanes) > + return -ENOMEM; > + > + for (i = 0; i < ssdb->lanes; i++) > + sensor->data_lanes[i] = i + 1; > + > + ep_properties[0] = PROPERTY_ENTRY_U32("bus-type", 5); > + ep_properties[1] = PROPERTY_ENTRY_U32_ARRAY_LEN("data-lanes", > + sensor->data_lanes, > + ssdb->lanes); > + ep_properties[2] = remote_endpoints[(bridge.n_sensors * 2) + ENDPOINT_SENSOR]; > + > + /* cio2 endpoint props */ > + memset(cio2_properties, 0, sizeof(struct property_entry) * 3); > + > + cio2_properties[0] = PROPERTY_ENTRY_U32_ARRAY_LEN("data-lanes", > + sensor->data_lanes, > + ssdb->lanes); > + cio2_properties[1] = remote_endpoints[(bridge.n_sensors * 2) + ENDPOINT_CIO2]; > + > + return 0; > +} > + > +static int create_connection_swnodes(struct sensor *sensor, > + struct sensor_bios_data *ssdb) > +{ > + struct software_node *nodes = sensor->swnodes; > + > + memset(nodes, 0, sizeof(struct software_node) * 6); > + > + nodes[SWNODE_SENSOR_HID] = NODE_SENSOR(sensor->name, > + sensor->dev_properties); > + nodes[SWNODE_SENSOR_PORT] = NODE_PORT("port0", > + &nodes[SWNODE_SENSOR_HID]); > + nodes[SWNODE_SENSOR_ENDPOINT] = NODE_ENDPOINT("endpoint0", > + &nodes[SWNODE_SENSOR_PORT], > + sensor->ep_properties); > + nodes[SWNODE_CIO2_PORT] = NODE_PORT(port_names[ssdb->link], > + &cio2_hid_node); > + nodes[SWNODE_CIO2_ENDPOINT] = NODE_ENDPOINT("endpoint0", > + &nodes[SWNODE_CIO2_PORT], > + sensor->cio2_properties); > + > + return 0; > +} > + > +static void cio2_bridge_unregister_sensors(void) > +{ > + struct sensor *sensor; > + int i; > + > + for (i = 0; i < bridge.n_sensors; i++) { > + sensor = &bridge.sensors[i]; > + > + software_node_unregister_nodes_reverse(sensor->swnodes); > + > + kfree(sensor->data_lanes); > + > + put_device(sensor->dev); > + acpi_dev_put(sensor->adev); > + } > +} > + > +static int connect_supported_devices(struct pci_dev *cio2) > +{ > + struct sensor_bios_data ssdb; > + struct fwnode_handle *fwnode; > + struct acpi_device *adev; > + struct sensor *sensor; > + struct device *dev; > + int i, ret; > + > + ret = 0; You can initialize ret to 0 when declaring the variable. > + for (i = 0; i < ARRAY_SIZE(supported_devices); i++) { > + adev = acpi_dev_get_first_match_dev(supported_devices[i], NULL, -1); What if there are multiple sensor of the same model ? > + if (!adev) > + continue; > + Does acpi_dev_get_first_match_dev() skip disabled devices (as reported by _STA) ? > + dev = bus_find_device_by_acpi_dev(&i2c_bus_type, adev); > + if (!dev) { > + ret = -EPROBE_DEFER; > + goto err_rollback; > + } > + > + sensor = &bridge.sensors[bridge.n_sensors]; > + sensor->dev = dev; > + sensor->adev = adev; > + > + snprintf(sensor->name, ACPI_ID_LEN, "%s", > + supported_devices[i]); How about strlcpy() ? > + > + ret = get_acpi_ssdb_sensor_data(dev, &ssdb); > + if (ret) > + goto err_free_dev; > + > + ret = create_fwnode_properties(sensor, &ssdb); > + if (ret) > + goto err_free_dev; > + > + ret = create_connection_swnodes(sensor, &ssdb); > + if (ret) > + goto err_free_dev; > + > + ret = software_node_register_nodes(sensor->swnodes); > + if (ret) > + goto err_free_dev; > + > + fwnode = software_node_fwnode(&sensor->swnodes[SWNODE_SENSOR_HID]); > + if (!fwnode) { > + ret = -ENODEV; > + goto err_free_swnodes; > + } > + > + set_secondary_fwnode(dev, fwnode); I wonder if we could avoid depending on the I2C device being created by getting the fwnode from adev, and setting ->secondary manually. adev would need to be passed to get_acpi_ssdb_sensor_data() instead of dev. > + > + dev_info(&cio2->dev, "Found supported device %s\n", > + supported_devices[i]); > + > + bridge.n_sensors++; > + continue; > + } > + > + return ret; > + > +err_free_swnodes: > + software_node_unregister_nodes_reverse(sensor->swnodes); > +err_free_dev: > + put_device(dev); > +err_rollback: > + acpi_dev_put(adev); I think you'll leak sensor->data_lanes here. It won't be a problem if you don't allocate it manually, as proposed above. I however wonder if error handling couldn't be simplified by increasing bridge.n_sensors earlier, and skipping cleanup in cio2_bridge_unregister_sensors() for the fields that haven't been initialized (for instance kfree() is a no-op on NULL pointers, so that's already handled). > + > + /* > + * If an iteration of this loop results in -EPROBE_DEFER then > + * we need to roll back any sensors that were successfully > + * registered. Any other error and we'll skip that step, as > + * it seems better to have one successfully connected sensor. > + */ > + > + if (ret == -EPROBE_DEFER) > + cio2_bridge_unregister_sensors(); > + > + return ret; > +} > + > +int cio2_bridge_build(struct pci_dev *cio2) > +{ > + struct fwnode_handle *fwnode; > + int ret; > + > + pci_dev_get(cio2); > + > + ret = software_node_register(&cio2_hid_node); > + if (ret < 0) { > + dev_err(&cio2->dev, "Failed to register the CIO2 HID node\n"); > + goto err_put_cio2; > + } > + > + ret = connect_supported_devices(cio2); > + if (ret == -EPROBE_DEFER) > + goto err_unregister_cio2; > + > + if (bridge.n_sensors == 0) { > + ret = -EPROBE_DEFER; > + goto err_unregister_cio2; > + } > + > + dev_info(&cio2->dev, "Connected %d cameras\n", bridge.n_sensors); > + > + fwnode = software_node_fwnode(&cio2_hid_node); > + if (!fwnode) { > + dev_err(&cio2->dev, > + "Error getting fwnode from cio2 software_node\n"); > + ret = -ENODEV; > + goto err_unregister_sensors; > + } > + > + set_secondary_fwnode(&cio2->dev, fwnode); > + > + return 0; > + > +err_unregister_sensors: > + cio2_bridge_unregister_sensors(); > +err_unregister_cio2: > + software_node_unregister(&cio2_hid_node); > +err_put_cio2: > + pci_dev_put(cio2); > + > + return ret; > +} > + > +void cio2_bridge_burn(struct pci_dev *cio2) Interesting function name :-) I like the creativity, but I think consistency with the rest of the kernel code should unfortunately be favoured. > +{ > + pci_dev_put(cio2); > + > + cio2_bridge_unregister_sensors(); > + > + software_node_unregister(&cio2_hid_node); > +} > 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 000000000..077354ca8 > --- /dev/null > +++ b/drivers/media/pci/intel/ipu3/cio2-bridge.h > @@ -0,0 +1,94 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* Author: Dan Scally <djrscally@xxxxxxxxx> */ > +#ifndef __CIO2_BRIDGE_H > +#define __CIO2_BRIDGE_H > + > +#define MAX_CONNECTED_DEVICES 4 > +#define SWNODE_SENSOR_HID 0 > +#define SWNODE_SENSOR_PORT 1 > +#define SWNODE_SENSOR_ENDPOINT 2 > +#define SWNODE_CIO2_PORT 3 > +#define SWNODE_CIO2_ENDPOINT 4 > +#define SWNODE_NULL_TERMINATOR 5 > + > +#define CIO2_HID "INT343E" > +#define CIO2_PCI_ID 0x9d32 > + > +#define ENDPOINT_SENSOR 0 > +#define ENDPOINT_CIO2 1 > + > +#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, \ > + }) > + > +#define NODE_ENDPOINT(_EP, _PORT, _PROPS) \ > + ((const struct software_node) { \ > + _EP, \ > + _PORT, \ > + _PROPS, \ > + }) > + > +struct sensor { That's a very common name, prone to namespace clashes. How about naming it cio2_sensor ? > + char name[ACPI_ID_LEN]; > + struct device *dev; > + struct acpi_device *adev; > + struct software_node swnodes[6]; > + struct property_entry dev_properties[3]; > + struct property_entry ep_properties[4]; > + struct property_entry cio2_properties[3]; > + u32 *data_lanes; > +}; > + > +struct cio2_bridge { > + int n_sensors; This can never be negative, I would make it an unsigned int. > + struct sensor sensors[MAX_CONNECTED_DEVICES]; > +}; > + > +/* Data representation as it is in ACPI SSDB buffer */ > +struct sensor_bios_data_packed { Similarly as above, I'd use a cio2_ prefix, and I think you can drop the _packed suffix. How about naming it cio2_sensor_ssdb_data (or even just cio2_sensor_ssdb) to make it clearer that it contains the SSDB data ? > + 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__; > + > +/* Fields needed by bridge driver */ > +struct sensor_bios_data { And cio2_sensor_data ? > + struct device *dev; > + u8 link; > + u8 lanes; > + u8 degree; > + u32 mclkspeed; > +}; > + > +#endif > diff --git a/drivers/media/pci/intel/ipu3/ipu3-cio2-main.c b/drivers/media/pci/intel/ipu3/ipu3-cio2-main.c > index f68ef0f6b..827457110 100644 > --- a/drivers/media/pci/intel/ipu3/ipu3-cio2-main.c > +++ b/drivers/media/pci/intel/ipu3/ipu3-cio2-main.c > @@ -1715,9 +1715,27 @@ static void cio2_queues_exit(struct cio2_device *cio2) > static int cio2_pci_probe(struct pci_dev *pci_dev, > const struct pci_device_id *id) > { > + struct fwnode_handle *endpoint; > struct cio2_device *cio2; > int r; > > + /* > + * 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. > + * > + * This may EPROBE_DEFER if supported devices are found defined in ACPI > + * but not yet ready for use (either not attached to the i2c bus yet, > + * or not done probing themselves). Why do we need for the I2C devices to be probed, isn't it enough to have them created ? > + */ > + > + endpoint = fwnode_graph_get_next_endpoint(dev_fwnode(&pci_dev->dev), NULL); > + if (!endpoint) { > + r = cio2_bridge_build(pci_dev); > + if (r) > + return r; > + } > + > cio2 = devm_kzalloc(&pci_dev->dev, sizeof(*cio2), GFP_KERNEL); > if (!cio2) > return -ENOMEM; > @@ -1825,6 +1843,9 @@ static void cio2_pci_remove(struct pci_dev *pci_dev) > { > struct cio2_device *cio2 = pci_get_drvdata(pci_dev); > > + if (is_software_node(dev_fwnode(&pci_dev->dev))) > + cio2_bridge_burn(pci_dev); > + > media_device_unregister(&cio2->media_dev); > v4l2_async_notifier_unregister(&cio2->notifier); > v4l2_async_notifier_cleanup(&cio2->notifier); > diff --git a/drivers/media/pci/intel/ipu3/ipu3-cio2.h b/drivers/media/pci/intel/ipu3/ipu3-cio2.h > index 549b08f88..80a081d7e 100644 > --- a/drivers/media/pci/intel/ipu3/ipu3-cio2.h > +++ b/drivers/media/pci/intel/ipu3/ipu3-cio2.h > @@ -436,4 +436,13 @@ static inline struct cio2_queue *vb2q_to_cio2_queue(struct vb2_queue *vq) > return container_of(vq, struct cio2_queue, vbq); > } > > +#if IS_ENABLED(CONFIG_CIO2_BRIDGE) > + int cio2_bridge_build(struct pci_dev *cio2); > + void cio2_bridge_burn(struct pci_dev *cio2); No need for an extra indentation level, neither here, not below. > +#else > + NO need for this blank line. > + int cio2_bridge_build(struct pci_dev *cio2) { return 0; } > + void cio2_bridge_burn(struct pci_dev *cio2) { } > +#endif > + > #endif -- Regards, Laurent Pinchart