diff options
Diffstat (limited to 'drivers/uwb/whc-rc.c')
-rw-r--r-- | drivers/uwb/whc-rc.c | 467 |
1 files changed, 0 insertions, 467 deletions
diff --git a/drivers/uwb/whc-rc.c b/drivers/uwb/whc-rc.c deleted file mode 100644 index 22397f70dee2..000000000000 --- a/drivers/uwb/whc-rc.c +++ /dev/null @@ -1,467 +0,0 @@ -// 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"); |