diff options
Diffstat (limited to 'drivers/misc/mic/bus/mic_bus.c')
| -rw-r--r-- | drivers/misc/mic/bus/mic_bus.c | 218 | 
1 files changed, 218 insertions, 0 deletions
diff --git a/drivers/misc/mic/bus/mic_bus.c b/drivers/misc/mic/bus/mic_bus.c new file mode 100644 index 000000000000..961ae90aae47 --- /dev/null +++ b/drivers/misc/mic/bus/mic_bus.c @@ -0,0 +1,218 @@ +/* + * Intel MIC Platform Software Stack (MPSS) + * + * Copyright(c) 2014 Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 2, as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * The full GNU General Public License is included in this distribution in + * the file called "COPYING". + * + * Intel MIC Bus driver. + * + * This implementation is very similar to the the virtio bus driver + * implementation @ drivers/virtio/virtio.c + */ +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/idr.h> +#include <linux/mic_bus.h> + +/* Unique numbering for mbus devices. */ +static DEFINE_IDA(mbus_index_ida); + +static ssize_t device_show(struct device *d, +			   struct device_attribute *attr, char *buf) +{ +	struct mbus_device *dev = dev_to_mbus(d); +	return sprintf(buf, "0x%04x\n", dev->id.device); +} +static DEVICE_ATTR_RO(device); + +static ssize_t vendor_show(struct device *d, +			   struct device_attribute *attr, char *buf) +{ +	struct mbus_device *dev = dev_to_mbus(d); +	return sprintf(buf, "0x%04x\n", dev->id.vendor); +} +static DEVICE_ATTR_RO(vendor); + +static ssize_t modalias_show(struct device *d, +			     struct device_attribute *attr, char *buf) +{ +	struct mbus_device *dev = dev_to_mbus(d); +	return sprintf(buf, "mbus:d%08Xv%08X\n", +		       dev->id.device, dev->id.vendor); +} +static DEVICE_ATTR_RO(modalias); + +static struct attribute *mbus_dev_attrs[] = { +	&dev_attr_device.attr, +	&dev_attr_vendor.attr, +	&dev_attr_modalias.attr, +	NULL, +}; +ATTRIBUTE_GROUPS(mbus_dev); + +static inline int mbus_id_match(const struct mbus_device *dev, +				const struct mbus_device_id *id) +{ +	if (id->device != dev->id.device && id->device != MBUS_DEV_ANY_ID) +		return 0; + +	return id->vendor == MBUS_DEV_ANY_ID || id->vendor == dev->id.vendor; +} + +/* + * This looks through all the IDs a driver claims to support.  If any of them + * match, we return 1 and the kernel will call mbus_dev_probe(). + */ +static int mbus_dev_match(struct device *dv, struct device_driver *dr) +{ +	unsigned int i; +	struct mbus_device *dev = dev_to_mbus(dv); +	const struct mbus_device_id *ids; + +	ids = drv_to_mbus(dr)->id_table; +	for (i = 0; ids[i].device; i++) +		if (mbus_id_match(dev, &ids[i])) +			return 1; +	return 0; +} + +static int mbus_uevent(struct device *dv, struct kobj_uevent_env *env) +{ +	struct mbus_device *dev = dev_to_mbus(dv); + +	return add_uevent_var(env, "MODALIAS=mbus:d%08Xv%08X", +			      dev->id.device, dev->id.vendor); +} + +static int mbus_dev_probe(struct device *d) +{ +	int err; +	struct mbus_device *dev = dev_to_mbus(d); +	struct mbus_driver *drv = drv_to_mbus(dev->dev.driver); + +	err = drv->probe(dev); +	if (!err) +		if (drv->scan) +			drv->scan(dev); +	return err; +} + +static int mbus_dev_remove(struct device *d) +{ +	struct mbus_device *dev = dev_to_mbus(d); +	struct mbus_driver *drv = drv_to_mbus(dev->dev.driver); + +	drv->remove(dev); +	return 0; +} + +static struct bus_type mic_bus = { +	.name  = "mic_bus", +	.match = mbus_dev_match, +	.dev_groups = mbus_dev_groups, +	.uevent = mbus_uevent, +	.probe = mbus_dev_probe, +	.remove = mbus_dev_remove, +}; + +int mbus_register_driver(struct mbus_driver *driver) +{ +	driver->driver.bus = &mic_bus; +	return driver_register(&driver->driver); +} +EXPORT_SYMBOL_GPL(mbus_register_driver); + +void mbus_unregister_driver(struct mbus_driver *driver) +{ +	driver_unregister(&driver->driver); +} +EXPORT_SYMBOL_GPL(mbus_unregister_driver); + +static void mbus_release_dev(struct device *d) +{ +	struct mbus_device *mbdev = dev_to_mbus(d); +	kfree(mbdev); +} + +struct mbus_device * +mbus_register_device(struct device *pdev, int id, struct dma_map_ops *dma_ops, +		     struct mbus_hw_ops *hw_ops, void __iomem *mmio_va) +{ +	int ret; +	struct mbus_device *mbdev; + +	mbdev = kzalloc(sizeof(*mbdev), GFP_KERNEL); +	if (!mbdev) +		return ERR_PTR(-ENOMEM); + +	mbdev->mmio_va = mmio_va; +	mbdev->dev.parent = pdev; +	mbdev->id.device = id; +	mbdev->id.vendor = MBUS_DEV_ANY_ID; +	mbdev->dev.archdata.dma_ops = dma_ops; +	mbdev->dev.dma_mask = &mbdev->dev.coherent_dma_mask; +	dma_set_mask(&mbdev->dev, DMA_BIT_MASK(64)); +	mbdev->dev.release = mbus_release_dev; +	mbdev->hw_ops = hw_ops; +	mbdev->dev.bus = &mic_bus; + +	/* Assign a unique device index and hence name. */ +	ret = ida_simple_get(&mbus_index_ida, 0, 0, GFP_KERNEL); +	if (ret < 0) +		goto free_mbdev; + +	mbdev->index = ret; +	dev_set_name(&mbdev->dev, "mbus-dev%u", mbdev->index); +	/* +	 * device_register() causes the bus infrastructure to look for a +	 * matching driver. +	 */ +	ret = device_register(&mbdev->dev); +	if (ret) +		goto ida_remove; +	return mbdev; +ida_remove: +	ida_simple_remove(&mbus_index_ida, mbdev->index); +free_mbdev: +	kfree(mbdev); +	return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(mbus_register_device); + +void mbus_unregister_device(struct mbus_device *mbdev) +{ +	int index = mbdev->index; /* save for after device release */ + +	device_unregister(&mbdev->dev); +	ida_simple_remove(&mbus_index_ida, index); +} +EXPORT_SYMBOL_GPL(mbus_unregister_device); + +static int __init mbus_init(void) +{ +	return bus_register(&mic_bus); +} + +static void __exit mbus_exit(void) +{ +	bus_unregister(&mic_bus); +	ida_destroy(&mbus_index_ida); +} + +core_initcall(mbus_init); +module_exit(mbus_exit); + +MODULE_AUTHOR("Intel Corporation"); +MODULE_DESCRIPTION("Intel(R) MIC Bus driver"); +MODULE_LICENSE("GPL v2");  | 
