linux/drivers/uwb/whc-rc.c

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/*
* 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>
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*
*
* 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 cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#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 = umc_dev->resource.end - umc_dev->resource.start + 1;
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");