| /* |
| * 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 <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"); |