[mirror_ubuntu-eoan-kernel.git] / drivers / uwb / whc-rc.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Wireless Host Controller: Radio Control Interface (WHCI v0.95[2.3])
 * Radio Control command/event transport to the UWB stack
 *
 * Copyright (C) 2005-2006 Intel Corporation
 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
 *
 * Initialize and hook up the Radio Control interface.
 *
 * For each device probed, creates an 'struct whcrc' which contains
 * just the representation of the UWB Radio Controller, and the logic
 * for reading notifications and passing them to the UWB Core.
 *
 * So we initialize all of those, register the UWB Radio Controller
 * and setup the notification/event handle to pipe the notifications
 * to the UWB management Daemon.
 *
 * Once uwb_rc_add() is called, the UWB stack takes control, resets
 * the radio and readies the device to take commands the UWB
 * API/user-space.
 *
 * Note this driver is just a transport driver; the commands are
 * formed at the UWB stack and given to this driver who will deliver
 * them to the hw and transfer the replies/notifications back to the
 * UWB stack through the UWB daemon (UWBD).
 */
#include <linux/init.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/sched.h>
#include <linux/dma-mapping.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/workqueue.h>
#include <linux/uwb.h>
#include <linux/uwb/whci.h>
#include <linux/uwb/umc.h>

#include "uwb-internal.h"

/**
 * Descriptor for an instance of the UWB Radio Control Driver that
 * attaches to the URC interface of the WHCI PCI card.
 *
 * Unless there is a lock specific to the 'data members', all access
 * is protected by uwb_rc->mutex.
 */
struct whcrc {
	struct umc_dev *umc_dev;
	struct uwb_rc *uwb_rc;		/* UWB host controller */

	unsigned long area;
	void __iomem *rc_base;
	size_t rc_len;
	spinlock_t irq_lock;

	void *evt_buf, *cmd_buf;
	dma_addr_t evt_dma_buf, cmd_dma_buf;
	wait_queue_head_t cmd_wq;
	struct work_struct event_work;
};

/**
 * Execute an UWB RC command on WHCI/RC
 *
 * @rc:       Instance of a Radio Controller that is a whcrc
 * @cmd:      Buffer containing the RCCB and payload to execute
 * @cmd_size: Size of the command buffer.
 *
 * We copy the command into whcrc->cmd_buf (as it is pretty and
 * aligned`and physically contiguous) and then press the right keys in
 * the controller's URCCMD register to get it to read it. We might
 * have to wait for the cmd_sem to be open to us.
 *
 * NOTE: rc's mutex has to be locked
 */
static int whcrc_cmd(struct uwb_rc *uwb_rc,
	      const struct uwb_rccb *cmd, size_t cmd_size)
{
	int result = 0;
	struct whcrc *whcrc = uwb_rc->priv;
	struct device *dev = &whcrc->umc_dev->dev;
	u32 urccmd;

	if (cmd_size >= 4096)
		return -EINVAL;

	/*
	 * If the URC is halted, then the hardware has reset itself.
	 * Attempt to recover by restarting the device and then return
	 * an error as it's likely that the current command isn't
	 * valid for a newly started RC.
	 */
	if (le_readl(whcrc->rc_base + URCSTS) & URCSTS_HALTED) {
		dev_err(dev, "requesting reset of halted radio controller\n");
		uwb_rc_reset_all(uwb_rc);
		return -EIO;
	}

	result = wait_event_timeout(whcrc->cmd_wq,
		!(le_readl(whcrc->rc_base + URCCMD) & URCCMD_ACTIVE), HZ/2);
	if (result == 0) {
		dev_err(dev, "device is not ready to execute commands\n");
		return -ETIMEDOUT;
	}

	memmove(whcrc->cmd_buf, cmd, cmd_size);
	le_writeq(whcrc->cmd_dma_buf, whcrc->rc_base + URCCMDADDR);

	spin_lock(&whcrc->irq_lock);
	urccmd = le_readl(whcrc->rc_base + URCCMD);
	urccmd &= ~(URCCMD_EARV | URCCMD_SIZE_MASK);
	le_writel(urccmd | URCCMD_ACTIVE | URCCMD_IWR | cmd_size,
		  whcrc->rc_base + URCCMD);
	spin_unlock(&whcrc->irq_lock);

	return 0;
}

static int whcrc_reset(struct uwb_rc *rc)
{
	struct whcrc *whcrc = rc->priv;

	return umc_controller_reset(whcrc->umc_dev);
}

/**
 * Reset event reception mechanism and tell hw we are ready to get more
 *
 * We have read all the events in the event buffer, so we are ready to
 * reset it to the beginning.
 *
 * This is only called during initialization or after an event buffer
 * has been retired.  This means we can be sure that event processing
 * is disabled and it's safe to update the URCEVTADDR register.
 *
 * There's no need to wait for the event processing to start as the
 * URC will not clear URCCMD_ACTIVE until (internal) event buffer
 * space is available.
 */
static
void whcrc_enable_events(struct whcrc *whcrc)
{
	u32 urccmd;

	le_writeq(whcrc->evt_dma_buf, whcrc->rc_base + URCEVTADDR);

	spin_lock(&whcrc->irq_lock);
	urccmd = le_readl(whcrc->rc_base + URCCMD) & ~URCCMD_ACTIVE;
	le_writel(urccmd | URCCMD_EARV, whcrc->rc_base + URCCMD);
	spin_unlock(&whcrc->irq_lock);
}

static void whcrc_event_work(struct work_struct *work)
{
	struct whcrc *whcrc = container_of(work, struct whcrc, event_work);
	size_t size;
	u64 urcevtaddr;

	urcevtaddr = le_readq(whcrc->rc_base + URCEVTADDR);
	size = urcevtaddr & URCEVTADDR_OFFSET_MASK;

	uwb_rc_neh_grok(whcrc->uwb_rc, whcrc->evt_buf, size);
	whcrc_enable_events(whcrc);
}

/**
 * Catch interrupts?
 *
 * We ack inmediately (and expect the hw to do the right thing and
 * raise another IRQ if things have changed :)
 */
static
irqreturn_t whcrc_irq_cb(int irq, void *_whcrc)
{
	struct whcrc *whcrc = _whcrc;
	struct device *dev = &whcrc->umc_dev->dev;
	u32 urcsts;

	urcsts = le_readl(whcrc->rc_base + URCSTS);
	if (!(urcsts & URCSTS_INT_MASK))
		return IRQ_NONE;
	le_writel(urcsts & URCSTS_INT_MASK, whcrc->rc_base + URCSTS);

	if (urcsts & URCSTS_HSE) {
		dev_err(dev, "host system error -- hardware halted\n");
		/* FIXME: do something sensible here */
		goto out;
	}
	if (urcsts & URCSTS_ER)
		schedule_work(&whcrc->event_work);
	if (urcsts & URCSTS_RCI)
		wake_up_all(&whcrc->cmd_wq);
out:
	return IRQ_HANDLED;
}


/**
 * Initialize a UMC RC interface: map regions, get (shared) IRQ
 */
static
int whcrc_setup_rc_umc(struct whcrc *whcrc)
{
	int result = 0;
	struct device *dev = &whcrc->umc_dev->dev;
	struct umc_dev *umc_dev = whcrc->umc_dev;

	whcrc->area = umc_dev->resource.start;
	whcrc->rc_len = resource_size(&umc_dev->resource);
	result = -EBUSY;
	if (request_mem_region(whcrc->area, whcrc->rc_len, KBUILD_MODNAME) == NULL) {
		dev_err(dev, "can't request URC region (%zu bytes @ 0x%lx): %d\n",
			whcrc->rc_len, whcrc->area, result);
		goto error_request_region;
	}

	whcrc->rc_base = ioremap_nocache(whcrc->area, whcrc->rc_len);
	if (whcrc->rc_base == NULL) {
		dev_err(dev, "can't ioremap registers (%zu bytes @ 0x%lx): %d\n",
			whcrc->rc_len, whcrc->area, result);
		goto error_ioremap_nocache;
	}

	result = request_irq(umc_dev->irq, whcrc_irq_cb, IRQF_SHARED,
			     KBUILD_MODNAME, whcrc);
	if (result < 0) {
		dev_err(dev, "can't allocate IRQ %d: %d\n",
			umc_dev->irq, result);
		goto error_request_irq;
	}

	result = -ENOMEM;
	whcrc->cmd_buf = dma_alloc_coherent(&umc_dev->dev, PAGE_SIZE,
					    &whcrc->cmd_dma_buf, GFP_KERNEL);
	if (whcrc->cmd_buf == NULL) {
		dev_err(dev, "Can't allocate cmd transfer buffer\n");
		goto error_cmd_buffer;
	}

	whcrc->evt_buf = dma_alloc_coherent(&umc_dev->dev, PAGE_SIZE,
					    &whcrc->evt_dma_buf, GFP_KERNEL);
	if (whcrc->evt_buf == NULL) {
		dev_err(dev, "Can't allocate evt transfer buffer\n");
		goto error_evt_buffer;
	}
	return 0;

error_evt_buffer:
	dma_free_coherent(&umc_dev->dev, PAGE_SIZE, whcrc->cmd_buf,
			  whcrc->cmd_dma_buf);
error_cmd_buffer:
	free_irq(umc_dev->irq, whcrc);
error_request_irq:
	iounmap(whcrc->rc_base);
error_ioremap_nocache:
	release_mem_region(whcrc->area, whcrc->rc_len);
error_request_region:
	return result;
}


/**
 * Release RC's UMC resources
 */
static
void whcrc_release_rc_umc(struct whcrc *whcrc)
{
	struct umc_dev *umc_dev = whcrc->umc_dev;

	dma_free_coherent(&umc_dev->dev, PAGE_SIZE, whcrc->evt_buf,
			  whcrc->evt_dma_buf);
	dma_free_coherent(&umc_dev->dev, PAGE_SIZE, whcrc->cmd_buf,
			  whcrc->cmd_dma_buf);
	free_irq(umc_dev->irq, whcrc);
	iounmap(whcrc->rc_base);
	release_mem_region(whcrc->area, whcrc->rc_len);
}


/**
 * whcrc_start_rc - start a WHCI radio controller
 * @whcrc: the radio controller to start
 *
 * Reset the UMC device, start the radio controller, enable events and
 * finally enable interrupts.
 */
static int whcrc_start_rc(struct uwb_rc *rc)
{
	struct whcrc *whcrc = rc->priv;
	struct device *dev = &whcrc->umc_dev->dev;

	/* Reset the thing */
	le_writel(URCCMD_RESET, whcrc->rc_base + URCCMD);
	if (whci_wait_for(dev, whcrc->rc_base + URCCMD, URCCMD_RESET, 0,
			  5000, "hardware reset") < 0)
		return -EBUSY;

	/* Set the event buffer, start the controller (enable IRQs later) */
	le_writel(0, whcrc->rc_base + URCINTR);
	le_writel(URCCMD_RS, whcrc->rc_base + URCCMD);
	if (whci_wait_for(dev, whcrc->rc_base + URCSTS, URCSTS_HALTED, 0,
			  5000, "radio controller start") < 0)
		return -ETIMEDOUT;
	whcrc_enable_events(whcrc);
	le_writel(URCINTR_EN_ALL, whcrc->rc_base + URCINTR);
	return 0;
}


/**
 * whcrc_stop_rc - stop a WHCI radio controller
 * @whcrc: the radio controller to stop
 *
 * Disable interrupts and cancel any pending event processing work
 * before clearing the Run/Stop bit.
 */
static
void whcrc_stop_rc(struct uwb_rc *rc)
{
	struct whcrc *whcrc = rc->priv;
	struct umc_dev *umc_dev = whcrc->umc_dev;

	le_writel(0, whcrc->rc_base + URCINTR);
	cancel_work_sync(&whcrc->event_work);

	le_writel(0, whcrc->rc_base + URCCMD);
	whci_wait_for(&umc_dev->dev, whcrc->rc_base + URCSTS,
		      URCSTS_HALTED, URCSTS_HALTED, 100, "radio controller stop");
}

static void whcrc_init(struct whcrc *whcrc)
{
	spin_lock_init(&whcrc->irq_lock);
	init_waitqueue_head(&whcrc->cmd_wq);
	INIT_WORK(&whcrc->event_work, whcrc_event_work);
}

/**
 * Initialize the radio controller.
 *
 * NOTE: we setup whcrc->uwb_rc before calling uwb_rc_add(); in the
 *       IRQ handler we use that to determine if the hw is ready to
 *       handle events. Looks like a race condition, but it really is
 *       not.
 */
static
int whcrc_probe(struct umc_dev *umc_dev)
{
	int result;
	struct uwb_rc *uwb_rc;
	struct whcrc *whcrc;
	struct device *dev = &umc_dev->dev;

	result = -ENOMEM;
	uwb_rc = uwb_rc_alloc();
	if (uwb_rc == NULL) {
		dev_err(dev, "unable to allocate RC instance\n");
		goto error_rc_alloc;
	}
	whcrc = kzalloc(sizeof(*whcrc), GFP_KERNEL);
	if (whcrc == NULL) {
		dev_err(dev, "unable to allocate WHC-RC instance\n");
		goto error_alloc;
	}
	whcrc_init(whcrc);
	whcrc->umc_dev = umc_dev;

	result = whcrc_setup_rc_umc(whcrc);
	if (result < 0) {
		dev_err(dev, "Can't setup RC UMC interface: %d\n", result);
		goto error_setup_rc_umc;
	}
	whcrc->uwb_rc = uwb_rc;

	uwb_rc->owner = THIS_MODULE;
	uwb_rc->cmd   = whcrc_cmd;
	uwb_rc->reset = whcrc_reset;
	uwb_rc->start = whcrc_start_rc;
	uwb_rc->stop  = whcrc_stop_rc;

	result = uwb_rc_add(uwb_rc, dev, whcrc);
	if (result < 0)
		goto error_rc_add;
	umc_set_drvdata(umc_dev, whcrc);
	return 0;

error_rc_add:
	whcrc_release_rc_umc(whcrc);
error_setup_rc_umc:
	kfree(whcrc);
error_alloc:
	uwb_rc_put(uwb_rc);
error_rc_alloc:
	return result;
}

/**
 * Clean up the radio control resources
 *
 * When we up the command semaphore, everybody possibly held trying to
 * execute a command should be granted entry and then they'll see the
 * host is quiescing and up it (so it will chain to the next waiter).
 * This should not happen (in any case), as we can only remove when
 * there are no handles open...
 */
static void whcrc_remove(struct umc_dev *umc_dev)
{
	struct whcrc *whcrc = umc_get_drvdata(umc_dev);
	struct uwb_rc *uwb_rc = whcrc->uwb_rc;

	umc_set_drvdata(umc_dev, NULL);
	uwb_rc_rm(uwb_rc);
	whcrc_release_rc_umc(whcrc);
	kfree(whcrc);
	uwb_rc_put(uwb_rc);
}

static int whcrc_pre_reset(struct umc_dev *umc)
{
	struct whcrc *whcrc = umc_get_drvdata(umc);
	struct uwb_rc *uwb_rc = whcrc->uwb_rc;

	uwb_rc_pre_reset(uwb_rc);
	return 0;
}

static int whcrc_post_reset(struct umc_dev *umc)
{
	struct whcrc *whcrc = umc_get_drvdata(umc);
	struct uwb_rc *uwb_rc = whcrc->uwb_rc;

	return uwb_rc_post_reset(uwb_rc);
}

/* PCI device ID's that we handle [so it gets loaded] */
static struct pci_device_id __used whcrc_id_table[] = {
	{ PCI_DEVICE_CLASS(PCI_CLASS_WIRELESS_WHCI, ~0) },
	{ /* empty last entry */ }
};
MODULE_DEVICE_TABLE(pci, whcrc_id_table);

static struct umc_driver whcrc_driver = {
	.name       = "whc-rc",
	.cap_id     = UMC_CAP_ID_WHCI_RC,
	.probe      = whcrc_probe,
	.remove     = whcrc_remove,
	.pre_reset  = whcrc_pre_reset,
	.post_reset = whcrc_post_reset,
};

static int __init whcrc_driver_init(void)
{
	return umc_driver_register(&whcrc_driver);
}
module_init(whcrc_driver_init);

static void __exit whcrc_driver_exit(void)
{
	umc_driver_unregister(&whcrc_driver);
}
module_exit(whcrc_driver_exit);

MODULE_AUTHOR("Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>");
MODULE_DESCRIPTION("Wireless Host Controller Radio Control Driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
04672fe6	1	// SPDX-License-Identifier: GPL-2.0-only
b6e06983 IPG	2	/*
	3	* Wireless Host Controller: Radio Control Interface (WHCI v0.95[2.3])
	4	* Radio Control command/event transport to the UWB stack
	5	*
	6	* Copyright (C) 2005-2006 Intel Corporation
	7	* Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
	8	*
b6e06983 IPG	9	* Initialize and hook up the Radio Control interface.
	10	*
	11	* For each device probed, creates an 'struct whcrc' which contains
	12	* just the representation of the UWB Radio Controller, and the logic
	13	* for reading notifications and passing them to the UWB Core.
	14	*
	15	* So we initialize all of those, register the UWB Radio Controller
	16	* and setup the notification/event handle to pipe the notifications
	17	* to the UWB management Daemon.
	18	*
	19	* Once uwb_rc_add() is called, the UWB stack takes control, resets
	20	* the radio and readies the device to take commands the UWB
	21	* API/user-space.
	22	*
	23	* Note this driver is just a transport driver; the commands are
	24	* formed at the UWB stack and given to this driver who will deliver
	25	* them to the hw and transfer the replies/notifications back to the
	26	* UWB stack through the UWB daemon (UWBD).
	27	*/
b6e06983 IPG	28	#include <linux/init.h>
	29	#include <linux/module.h>
	30	#include <linux/pci.h>
d43c36dc	31	#include <linux/sched.h>
b6e06983 IPG	32	#include <linux/dma-mapping.h>
b6e06983 IPG	33	#include <linux/interrupt.h>
5a0e3ad6	34	#include <linux/slab.h>
b6e06983 IPG	35	#include <linux/workqueue.h>
	36	#include <linux/uwb.h>
	37	#include <linux/uwb/whci.h>
	38	#include <linux/uwb/umc.h>
b6e06983	39
bce83697	40	#include "uwb-internal.h"
b6e06983 IPG	41
	42	/**
	43	* Descriptor for an instance of the UWB Radio Control Driver that
	44	* attaches to the URC interface of the WHCI PCI card.
	45	*
	46	* Unless there is a lock specific to the 'data members', all access
	47	* is protected by uwb_rc->mutex.
	48	*/
	49	struct whcrc {
	50	struct umc_dev *umc_dev;
	51	struct uwb_rc uwb_rc; / UWB host controller */
	52
	53	unsigned long area;
	54	void __iomem *rc_base;
	55	size_t rc_len;
	56	spinlock_t irq_lock;
	57
	58	void evt_buf, cmd_buf;
	59	dma_addr_t evt_dma_buf, cmd_dma_buf;
	60	wait_queue_head_t cmd_wq;
	61	struct work_struct event_work;
	62	};
	63
	64	/**
	65	* Execute an UWB RC command on WHCI/RC
	66	*
	67	* @rc: Instance of a Radio Controller that is a whcrc
	68	* @cmd: Buffer containing the RCCB and payload to execute
	69	* @cmd_size: Size of the command buffer.
	70	*
	71	* We copy the command into whcrc->cmd_buf (as it is pretty and
	72	* aligned`and physically contiguous) and then press the right keys in
	73	* the controller's URCCMD register to get it to read it. We might
	74	* have to wait for the cmd_sem to be open to us.
	75	*
	76	* NOTE: rc's mutex has to be locked
	77	*/
	78	static int whcrc_cmd(struct uwb_rc *uwb_rc,
	79	const struct uwb_rccb *cmd, size_t cmd_size)
	80	{
	81	int result = 0;
	82	struct whcrc *whcrc = uwb_rc->priv;
	83	struct device *dev = &whcrc->umc_dev->dev;
	84	u32 urccmd;
	85
bce83697 DV	86	if (cmd_size >= 4096)
bce83697 DV	87	return -EINVAL;
b6e06983 IPG	88
	89	/*
	90	* If the URC is halted, then the hardware has reset itself.
	91	* Attempt to recover by restarting the device and then return
	92	* an error as it's likely that the current command isn't
	93	* valid for a newly started RC.
	94	*/
	95	if (le_readl(whcrc->rc_base + URCSTS) & URCSTS_HALTED) {
	96	dev_err(dev, "requesting reset of halted radio controller\n");
	97	uwb_rc_reset_all(uwb_rc);
bce83697	98	return -EIO;
b6e06983 IPG	99	}
	100
	101	result = wait_event_timeout(whcrc->cmd_wq,
	102	!(le_readl(whcrc->rc_base + URCCMD) & URCCMD_ACTIVE), HZ/2);
	103	if (result == 0) {
	104	dev_err(dev, "device is not ready to execute commands\n");
bce83697	105	return -ETIMEDOUT;
b6e06983 IPG	106	}
	107
	108	memmove(whcrc->cmd_buf, cmd, cmd_size);
	109	le_writeq(whcrc->cmd_dma_buf, whcrc->rc_base + URCCMDADDR);
	110
	111	spin_lock(&whcrc->irq_lock);
	112	urccmd = le_readl(whcrc->rc_base + URCCMD);
	113	urccmd &= ~(URCCMD_EARV \| URCCMD_SIZE_MASK);
	114	le_writel(urccmd \| URCCMD_ACTIVE \| URCCMD_IWR \| cmd_size,
	115	whcrc->rc_base + URCCMD);
	116	spin_unlock(&whcrc->irq_lock);
	117
bce83697	118	return 0;
b6e06983 IPG	119	}
	120
	121	static int whcrc_reset(struct uwb_rc *rc)
	122	{
	123	struct whcrc *whcrc = rc->priv;
	124
	125	return umc_controller_reset(whcrc->umc_dev);
	126	}
	127
	128	/**
	129	* Reset event reception mechanism and tell hw we are ready to get more
	130	*
	131	* We have read all the events in the event buffer, so we are ready to
	132	* reset it to the beginning.
	133	*
	134	* This is only called during initialization or after an event buffer
	135	* has been retired. This means we can be sure that event processing
	136	* is disabled and it's safe to update the URCEVTADDR register.
	137	*
	138	* There's no need to wait for the event processing to start as the
	139	* URC will not clear URCCMD_ACTIVE until (internal) event buffer
	140	* space is available.
	141	*/
	142	static
	143	void whcrc_enable_events(struct whcrc *whcrc)
	144	{
b6e06983 IPG	145	u32 urccmd;
b6e06983 IPG	146
b6e06983 IPG	147	le_writeq(whcrc->evt_dma_buf, whcrc->rc_base + URCEVTADDR);
	148
	149	spin_lock(&whcrc->irq_lock);
	150	urccmd = le_readl(whcrc->rc_base + URCCMD) & ~URCCMD_ACTIVE;
	151	le_writel(urccmd \| URCCMD_EARV, whcrc->rc_base + URCCMD);
	152	spin_unlock(&whcrc->irq_lock);
b6e06983 IPG	153	}
	154
	155	static void whcrc_event_work(struct work_struct *work)
	156	{
	157	struct whcrc *whcrc = container_of(work, struct whcrc, event_work);
b6e06983 IPG	158	size_t size;
	159	u64 urcevtaddr;
	160
	161	urcevtaddr = le_readq(whcrc->rc_base + URCEVTADDR);
	162	size = urcevtaddr & URCEVTADDR_OFFSET_MASK;
	163
b6e06983 IPG	164	uwb_rc_neh_grok(whcrc->uwb_rc, whcrc->evt_buf, size);
	165	whcrc_enable_events(whcrc);
	166	}
	167
	168	/**
	169	* Catch interrupts?
	170	*
	171	* We ack inmediately (and expect the hw to do the right thing and
	172	* raise another IRQ if things have changed :)
	173	*/
	174	static
	175	irqreturn_t whcrc_irq_cb(int irq, void *_whcrc)
	176	{
	177	struct whcrc *whcrc = _whcrc;
	178	struct device *dev = &whcrc->umc_dev->dev;
	179	u32 urcsts;
	180
b6e06983 IPG	181	urcsts = le_readl(whcrc->rc_base + URCSTS);
	182	if (!(urcsts & URCSTS_INT_MASK))
	183	return IRQ_NONE;
	184	le_writel(urcsts & URCSTS_INT_MASK, whcrc->rc_base + URCSTS);
	185
b6e06983 IPG	186	if (urcsts & URCSTS_HSE) {
	187	dev_err(dev, "host system error -- hardware halted\n");
	188	/* FIXME: do something sensible here */
	189	goto out;
	190	}
bce83697	191	if (urcsts & URCSTS_ER)
b6e06983	192	schedule_work(&whcrc->event_work);
bce83697	193	if (urcsts & URCSTS_RCI)
b6e06983	194	wake_up_all(&whcrc->cmd_wq);
b6e06983 IPG	195	out:
	196	return IRQ_HANDLED;
	197	}
	198
	199
	200	/**
	201	* Initialize a UMC RC interface: map regions, get (shared) IRQ
	202	*/
	203	static
	204	int whcrc_setup_rc_umc(struct whcrc *whcrc)
	205	{
	206	int result = 0;
	207	struct device *dev = &whcrc->umc_dev->dev;
	208	struct umc_dev *umc_dev = whcrc->umc_dev;
	209
	210	whcrc->area = umc_dev->resource.start;
28f65c11	211	whcrc->rc_len = resource_size(&umc_dev->resource);
b6e06983	212	result = -EBUSY;
bce83697	213	if (request_mem_region(whcrc->area, whcrc->rc_len, KBUILD_MODNAME) == NULL) {
b6e06983 IPG	214	dev_err(dev, "can't request URC region (%zu bytes @ 0x%lx): %d\n",
	215	whcrc->rc_len, whcrc->area, result);
	216	goto error_request_region;
	217	}
	218
	219	whcrc->rc_base = ioremap_nocache(whcrc->area, whcrc->rc_len);
	220	if (whcrc->rc_base == NULL) {
	221	dev_err(dev, "can't ioremap registers (%zu bytes @ 0x%lx): %d\n",
	222	whcrc->rc_len, whcrc->area, result);
	223	goto error_ioremap_nocache;
	224	}
	225
	226	result = request_irq(umc_dev->irq, whcrc_irq_cb, IRQF_SHARED,
	227	KBUILD_MODNAME, whcrc);
	228	if (result < 0) {
	229	dev_err(dev, "can't allocate IRQ %d: %d\n",
	230	umc_dev->irq, result);
	231	goto error_request_irq;
	232	}
	233
	234	result = -ENOMEM;
	235	whcrc->cmd_buf = dma_alloc_coherent(&umc_dev->dev, PAGE_SIZE,
	236	&whcrc->cmd_dma_buf, GFP_KERNEL);
	237	if (whcrc->cmd_buf == NULL) {
	238	dev_err(dev, "Can't allocate cmd transfer buffer\n");
	239	goto error_cmd_buffer;
	240	}
	241
	242	whcrc->evt_buf = dma_alloc_coherent(&umc_dev->dev, PAGE_SIZE,
	243	&whcrc->evt_dma_buf, GFP_KERNEL);
	244	if (whcrc->evt_buf == NULL) {
	245	dev_err(dev, "Can't allocate evt transfer buffer\n");
	246	goto error_evt_buffer;
	247	}
b6e06983 IPG	248	return 0;
	249
	250	error_evt_buffer:
	251	dma_free_coherent(&umc_dev->dev, PAGE_SIZE, whcrc->cmd_buf,
	252	whcrc->cmd_dma_buf);
	253	error_cmd_buffer:
	254	free_irq(umc_dev->irq, whcrc);
	255	error_request_irq:
	256	iounmap(whcrc->rc_base);
	257	error_ioremap_nocache:
	258	release_mem_region(whcrc->area, whcrc->rc_len);
	259	error_request_region:
	260	return result;
	261	}
	262
	263
	264	/**
	265	* Release RC's UMC resources
	266	*/
	267	static
	268	void whcrc_release_rc_umc(struct whcrc *whcrc)
	269	{
	270	struct umc_dev *umc_dev = whcrc->umc_dev;
	271
	272	dma_free_coherent(&umc_dev->dev, PAGE_SIZE, whcrc->evt_buf,
	273	whcrc->evt_dma_buf);
	274	dma_free_coherent(&umc_dev->dev, PAGE_SIZE, whcrc->cmd_buf,
	275	whcrc->cmd_dma_buf);
	276	free_irq(umc_dev->irq, whcrc);
	277	iounmap(whcrc->rc_base);
	278	release_mem_region(whcrc->area, whcrc->rc_len);
	279	}
	280
	281
	282	/**
	283	* whcrc_start_rc - start a WHCI radio controller
	284	* @whcrc: the radio controller to start
	285	*
	286	* Reset the UMC device, start the radio controller, enable events and
	287	* finally enable interrupts.
	288	*/
	289	static int whcrc_start_rc(struct uwb_rc *rc)
	290	{
	291	struct whcrc *whcrc = rc->priv;
b6e06983	292	struct device *dev = &whcrc->umc_dev->dev;
b6e06983 IPG	293
	294	/* Reset the thing */
	295	le_writel(URCCMD_RESET, whcrc->rc_base + URCCMD);
b6e06983	296	if (whci_wait_for(dev, whcrc->rc_base + URCCMD, URCCMD_RESET, 0,
5a4e1a79 DV	297	5000, "hardware reset") < 0)
5a4e1a79 DV	298	return -EBUSY;
b6e06983 IPG	299
	300	/* Set the event buffer, start the controller (enable IRQs later) */
	301	le_writel(0, whcrc->rc_base + URCINTR);
	302	le_writel(URCCMD_RS, whcrc->rc_base + URCCMD);
b6e06983	303	if (whci_wait_for(dev, whcrc->rc_base + URCSTS, URCSTS_HALTED, 0,
5a4e1a79 DV	304	5000, "radio controller start") < 0)
5a4e1a79 DV	305	return -ETIMEDOUT;
b6e06983	306	whcrc_enable_events(whcrc);
b6e06983	307	le_writel(URCINTR_EN_ALL, whcrc->rc_base + URCINTR);
5a4e1a79	308	return 0;
b6e06983 IPG	309	}
	310
	311
	312	/**
	313	* whcrc_stop_rc - stop a WHCI radio controller
	314	* @whcrc: the radio controller to stop
	315	*
	316	* Disable interrupts and cancel any pending event processing work
	317	* before clearing the Run/Stop bit.
	318	*/
	319	static
	320	void whcrc_stop_rc(struct uwb_rc *rc)
	321	{
	322	struct whcrc *whcrc = rc->priv;
	323	struct umc_dev *umc_dev = whcrc->umc_dev;
	324
	325	le_writel(0, whcrc->rc_base + URCINTR);
	326	cancel_work_sync(&whcrc->event_work);
	327
	328	le_writel(0, whcrc->rc_base + URCCMD);
	329	whci_wait_for(&umc_dev->dev, whcrc->rc_base + URCSTS,
5a4e1a79	330	URCSTS_HALTED, URCSTS_HALTED, 100, "radio controller stop");
b6e06983 IPG	331	}
	332
	333	static void whcrc_init(struct whcrc *whcrc)
	334	{
	335	spin_lock_init(&whcrc->irq_lock);
	336	init_waitqueue_head(&whcrc->cmd_wq);
	337	INIT_WORK(&whcrc->event_work, whcrc_event_work);
	338	}
	339
	340	/**
	341	* Initialize the radio controller.
	342	*
	343	* NOTE: we setup whcrc->uwb_rc before calling uwb_rc_add(); in the
	344	* IRQ handler we use that to determine if the hw is ready to
	345	* handle events. Looks like a race condition, but it really is
	346	* not.
	347	*/
	348	static
	349	int whcrc_probe(struct umc_dev *umc_dev)
	350	{
	351	int result;
	352	struct uwb_rc *uwb_rc;
	353	struct whcrc *whcrc;
	354	struct device *dev = &umc_dev->dev;
	355
b6e06983 IPG	356	result = -ENOMEM;
	357	uwb_rc = uwb_rc_alloc();
	358	if (uwb_rc == NULL) {
	359	dev_err(dev, "unable to allocate RC instance\n");
	360	goto error_rc_alloc;
	361	}
	362	whcrc = kzalloc(sizeof(*whcrc), GFP_KERNEL);
	363	if (whcrc == NULL) {
	364	dev_err(dev, "unable to allocate WHC-RC instance\n");
	365	goto error_alloc;
	366	}
	367	whcrc_init(whcrc);
	368	whcrc->umc_dev = umc_dev;
	369
	370	result = whcrc_setup_rc_umc(whcrc);
	371	if (result < 0) {
	372	dev_err(dev, "Can't setup RC UMC interface: %d\n", result);
	373	goto error_setup_rc_umc;
	374	}
	375	whcrc->uwb_rc = uwb_rc;
	376
	377	uwb_rc->owner = THIS_MODULE;
	378	uwb_rc->cmd = whcrc_cmd;
	379	uwb_rc->reset = whcrc_reset;
	380	uwb_rc->start = whcrc_start_rc;
	381	uwb_rc->stop = whcrc_stop_rc;
	382
	383	result = uwb_rc_add(uwb_rc, dev, whcrc);
	384	if (result < 0)
	385	goto error_rc_add;
	386	umc_set_drvdata(umc_dev, whcrc);
b6e06983 IPG	387	return 0;
	388
	389	error_rc_add:
	390	whcrc_release_rc_umc(whcrc);
	391	error_setup_rc_umc:
	392	kfree(whcrc);
	393	error_alloc:
	394	uwb_rc_put(uwb_rc);
	395	error_rc_alloc:
b6e06983 IPG	396	return result;
	397	}
	398
	399	/**
	400	* Clean up the radio control resources
	401	*
	402	* When we up the command semaphore, everybody possibly held trying to
	403	* execute a command should be granted entry and then they'll see the
	404	* host is quiescing and up it (so it will chain to the next waiter).
	405	* This should not happen (in any case), as we can only remove when
	406	* there are no handles open...
	407	*/
	408	static void whcrc_remove(struct umc_dev *umc_dev)
	409	{
	410	struct whcrc *whcrc = umc_get_drvdata(umc_dev);
	411	struct uwb_rc *uwb_rc = whcrc->uwb_rc;
	412
	413	umc_set_drvdata(umc_dev, NULL);
	414	uwb_rc_rm(uwb_rc);
	415	whcrc_release_rc_umc(whcrc);
	416	kfree(whcrc);
	417	uwb_rc_put(uwb_rc);
b6e06983 IPG	418	}
b6e06983 IPG	419
307ba6dd DV	420	static int whcrc_pre_reset(struct umc_dev *umc)
	421	{
	422	struct whcrc *whcrc = umc_get_drvdata(umc);
	423	struct uwb_rc *uwb_rc = whcrc->uwb_rc;
	424
	425	uwb_rc_pre_reset(uwb_rc);
	426	return 0;
	427	}
	428
	429	static int whcrc_post_reset(struct umc_dev *umc)
	430	{
	431	struct whcrc *whcrc = umc_get_drvdata(umc);
	432	struct uwb_rc *uwb_rc = whcrc->uwb_rc;
	433
0396c215	434	return uwb_rc_post_reset(uwb_rc);
307ba6dd DV	435	}
307ba6dd DV	436
b6e06983	437	/* PCI device ID's that we handle [so it gets loaded] */
fc33b0eb	438	static struct pci_device_id __used whcrc_id_table[] = {
b6e06983 IPG	439	{ PCI_DEVICE_CLASS(PCI_CLASS_WIRELESS_WHCI, ~0) },
	440	{ /* empty last entry */ }
	441	};
	442	MODULE_DEVICE_TABLE(pci, whcrc_id_table);
	443
	444	static struct umc_driver whcrc_driver = {
307ba6dd DV	445	.name = "whc-rc",
	446	.cap_id = UMC_CAP_ID_WHCI_RC,
	447	.probe = whcrc_probe,
	448	.remove = whcrc_remove,
	449	.pre_reset = whcrc_pre_reset,
	450	.post_reset = whcrc_post_reset,
b6e06983 IPG	451	};
	452
	453	static int __init whcrc_driver_init(void)
	454	{
	455	return umc_driver_register(&whcrc_driver);
	456	}
	457	module_init(whcrc_driver_init);
	458
	459	static void __exit whcrc_driver_exit(void)
	460	{
	461	umc_driver_unregister(&whcrc_driver);
	462	}
	463	module_exit(whcrc_driver_exit);
	464
	465	MODULE_AUTHOR("Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>");
	466	MODULE_DESCRIPTION("Wireless Host Controller Radio Control Driver");
	467	MODULE_LICENSE("GPL");