diff options
Diffstat (limited to 'drivers/misc/mei/gsc_proxy/mei_gsc_proxy.c')
| -rw-r--r-- | drivers/misc/mei/gsc_proxy/mei_gsc_proxy.c | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/drivers/misc/mei/gsc_proxy/mei_gsc_proxy.c b/drivers/misc/mei/gsc_proxy/mei_gsc_proxy.c new file mode 100644 index 000000000000..be52b113aea9 --- /dev/null +++ b/drivers/misc/mei/gsc_proxy/mei_gsc_proxy.c @@ -0,0 +1,208 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2022-2023 Intel Corporation + */ + +/** + * DOC: MEI_GSC_PROXY Client Driver + * + * The mei_gsc_proxy driver acts as a translation layer between + * proxy user (I915) and ME FW by proxying messages to ME FW + */ + +#include <linux/component.h> +#include <linux/mei_cl_bus.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/slab.h> +#include <linux/uuid.h> +#include <drm/drm_connector.h> +#include <drm/i915_component.h> +#include <drm/i915_gsc_proxy_mei_interface.h> + +/** + * mei_gsc_proxy_send - Sends a proxy message to ME FW. + * @dev: device corresponding to the mei_cl_device + * @buf: a message buffer to send + * @size: size of the message + * Return: bytes sent on Success, <0 on Failure + */ +static int mei_gsc_proxy_send(struct device *dev, const void *buf, size_t size) +{ + ssize_t ret; + + if (!dev || !buf) + return -EINVAL; + + ret = mei_cldev_send(to_mei_cl_device(dev), buf, size); + if (ret < 0) + dev_dbg(dev, "mei_cldev_send failed. %zd\n", ret); + + return ret; +} + +/** + * mei_gsc_proxy_recv - Receives a proxy message from ME FW. + * @dev: device corresponding to the mei_cl_device + * @buf: a message buffer to contain the received message + * @size: size of the buffer + * Return: bytes received on Success, <0 on Failure + */ +static int mei_gsc_proxy_recv(struct device *dev, void *buf, size_t size) +{ + ssize_t ret; + + if (!dev || !buf) + return -EINVAL; + + ret = mei_cldev_recv(to_mei_cl_device(dev), buf, size); + if (ret < 0) + dev_dbg(dev, "mei_cldev_recv failed. %zd\n", ret); + + return ret; +} + +static const struct i915_gsc_proxy_component_ops mei_gsc_proxy_ops = { + .owner = THIS_MODULE, + .send = mei_gsc_proxy_send, + .recv = mei_gsc_proxy_recv, +}; + +static int mei_component_master_bind(struct device *dev) +{ + struct mei_cl_device *cldev = to_mei_cl_device(dev); + struct i915_gsc_proxy_component *comp_master = mei_cldev_get_drvdata(cldev); + + comp_master->ops = &mei_gsc_proxy_ops; + comp_master->mei_dev = dev; + return component_bind_all(dev, comp_master); +} + +static void mei_component_master_unbind(struct device *dev) +{ + struct mei_cl_device *cldev = to_mei_cl_device(dev); + struct i915_gsc_proxy_component *comp_master = mei_cldev_get_drvdata(cldev); + + component_unbind_all(dev, comp_master); +} + +static const struct component_master_ops mei_component_master_ops = { + .bind = mei_component_master_bind, + .unbind = mei_component_master_unbind, +}; + +/** + * mei_gsc_proxy_component_match - compare function for matching mei. + * + * The function checks if the device is pci device and + * Intel VGA adapter, the subcomponent is SW Proxy + * and the parent of MEI PCI and the parent of VGA are the same PCH device. + * + * @dev: master device + * @subcomponent: subcomponent to match (I915_COMPONENT_SWPROXY) + * @data: compare data (mei pci parent) + * + * Return: + * * 1 - if components match + * * 0 - otherwise + */ +static int mei_gsc_proxy_component_match(struct device *dev, int subcomponent, + void *data) +{ + struct pci_dev *pdev; + + if (!dev_is_pci(dev)) + return 0; + + pdev = to_pci_dev(dev); + + if (pdev->class != (PCI_CLASS_DISPLAY_VGA << 8) || + pdev->vendor != PCI_VENDOR_ID_INTEL) + return 0; + + if (subcomponent != I915_COMPONENT_GSC_PROXY) + return 0; + + return component_compare_dev(dev->parent, ((struct device *)data)->parent); +} + +static int mei_gsc_proxy_probe(struct mei_cl_device *cldev, + const struct mei_cl_device_id *id) +{ + struct i915_gsc_proxy_component *comp_master; + struct component_match *master_match = NULL; + int ret; + + ret = mei_cldev_enable(cldev); + if (ret < 0) { + dev_err(&cldev->dev, "mei_cldev_enable Failed. %d\n", ret); + goto enable_err_exit; + } + + comp_master = kzalloc(sizeof(*comp_master), GFP_KERNEL); + if (!comp_master) { + ret = -ENOMEM; + goto err_exit; + } + + component_match_add_typed(&cldev->dev, &master_match, + mei_gsc_proxy_component_match, cldev->dev.parent); + if (IS_ERR_OR_NULL(master_match)) { + ret = -ENOMEM; + goto err_exit; + } + + mei_cldev_set_drvdata(cldev, comp_master); + ret = component_master_add_with_match(&cldev->dev, + &mei_component_master_ops, + master_match); + if (ret < 0) { + dev_err(&cldev->dev, "Master comp add failed %d\n", ret); + goto err_exit; + } + + return 0; + +err_exit: + mei_cldev_set_drvdata(cldev, NULL); + kfree(comp_master); + mei_cldev_disable(cldev); +enable_err_exit: + return ret; +} + +static void mei_gsc_proxy_remove(struct mei_cl_device *cldev) +{ + struct i915_gsc_proxy_component *comp_master = mei_cldev_get_drvdata(cldev); + int ret; + + component_master_del(&cldev->dev, &mei_component_master_ops); + kfree(comp_master); + mei_cldev_set_drvdata(cldev, NULL); + + ret = mei_cldev_disable(cldev); + if (ret) + dev_warn(&cldev->dev, "mei_cldev_disable() failed %d\n", ret); +} + +#define MEI_UUID_GSC_PROXY UUID_LE(0xf73db04, 0x97ab, 0x4125, \ + 0xb8, 0x93, 0xe9, 0x4, 0xad, 0xd, 0x54, 0x64) + +static struct mei_cl_device_id mei_gsc_proxy_tbl[] = { + { .uuid = MEI_UUID_GSC_PROXY, .version = MEI_CL_VERSION_ANY }, + { } +}; +MODULE_DEVICE_TABLE(mei, mei_gsc_proxy_tbl); + +static struct mei_cl_driver mei_gsc_proxy_driver = { + .id_table = mei_gsc_proxy_tbl, + .name = KBUILD_MODNAME, + .probe = mei_gsc_proxy_probe, + .remove = mei_gsc_proxy_remove, +}; + +module_mei_cl_driver(mei_gsc_proxy_driver); + +MODULE_AUTHOR("Intel Corporation"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("MEI GSC PROXY"); |