linux/drivers/usb/host/whci/hcd.c
Markus Elfring 28ed207558 USB: whci-hcd: Delete an unnecessary check before the function call "usb_put_hcd"
The usb_put_hcd() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-18 16:56:40 +01:00

367 lines
8.4 KiB
C

/*
* Wireless Host Controller (WHC) driver.
*
* Copyright (C) 2007 Cambridge Silicon Radio Ltd.
*
* 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, see <http://www.gnu.org/licenses/>.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/uwb/umc.h>
#include "../../wusbcore/wusbhc.h"
#include "whcd.h"
/*
* One time initialization.
*
* Nothing to do here.
*/
static int whc_reset(struct usb_hcd *usb_hcd)
{
return 0;
}
/*
* Start the wireless host controller.
*
* Start device notification.
*
* Put hc into run state, set DNTS parameters.
*/
static int whc_start(struct usb_hcd *usb_hcd)
{
struct wusbhc *wusbhc = usb_hcd_to_wusbhc(usb_hcd);
struct whc *whc = wusbhc_to_whc(wusbhc);
u8 bcid;
int ret;
mutex_lock(&wusbhc->mutex);
le_writel(WUSBINTR_GEN_CMD_DONE
| WUSBINTR_HOST_ERR
| WUSBINTR_ASYNC_SCHED_SYNCED
| WUSBINTR_DNTS_INT
| WUSBINTR_ERR_INT
| WUSBINTR_INT,
whc->base + WUSBINTR);
/* set cluster ID */
bcid = wusb_cluster_id_get();
ret = whc_set_cluster_id(whc, bcid);
if (ret < 0)
goto out;
wusbhc->cluster_id = bcid;
/* start HC */
whc_write_wusbcmd(whc, WUSBCMD_RUN, WUSBCMD_RUN);
usb_hcd->uses_new_polling = 1;
set_bit(HCD_FLAG_POLL_RH, &usb_hcd->flags);
usb_hcd->state = HC_STATE_RUNNING;
out:
mutex_unlock(&wusbhc->mutex);
return ret;
}
/*
* Stop the wireless host controller.
*
* Stop device notification.
*
* Wait for pending transfer to stop? Put hc into stop state?
*/
static void whc_stop(struct usb_hcd *usb_hcd)
{
struct wusbhc *wusbhc = usb_hcd_to_wusbhc(usb_hcd);
struct whc *whc = wusbhc_to_whc(wusbhc);
mutex_lock(&wusbhc->mutex);
/* stop HC */
le_writel(0, whc->base + WUSBINTR);
whc_write_wusbcmd(whc, WUSBCMD_RUN, 0);
whci_wait_for(&whc->umc->dev, whc->base + WUSBSTS,
WUSBSTS_HCHALTED, WUSBSTS_HCHALTED,
100, "HC to halt");
wusb_cluster_id_put(wusbhc->cluster_id);
mutex_unlock(&wusbhc->mutex);
}
static int whc_get_frame_number(struct usb_hcd *usb_hcd)
{
/* Frame numbers are not applicable to WUSB. */
return -ENOSYS;
}
/*
* Queue an URB to the ASL or PZL
*/
static int whc_urb_enqueue(struct usb_hcd *usb_hcd, struct urb *urb,
gfp_t mem_flags)
{
struct wusbhc *wusbhc = usb_hcd_to_wusbhc(usb_hcd);
struct whc *whc = wusbhc_to_whc(wusbhc);
int ret;
switch (usb_pipetype(urb->pipe)) {
case PIPE_INTERRUPT:
ret = pzl_urb_enqueue(whc, urb, mem_flags);
break;
case PIPE_ISOCHRONOUS:
dev_err(&whc->umc->dev, "isochronous transfers unsupported\n");
ret = -ENOTSUPP;
break;
case PIPE_CONTROL:
case PIPE_BULK:
default:
ret = asl_urb_enqueue(whc, urb, mem_flags);
break;
}
return ret;
}
/*
* Remove a queued URB from the ASL or PZL.
*/
static int whc_urb_dequeue(struct usb_hcd *usb_hcd, struct urb *urb, int status)
{
struct wusbhc *wusbhc = usb_hcd_to_wusbhc(usb_hcd);
struct whc *whc = wusbhc_to_whc(wusbhc);
int ret;
switch (usb_pipetype(urb->pipe)) {
case PIPE_INTERRUPT:
ret = pzl_urb_dequeue(whc, urb, status);
break;
case PIPE_ISOCHRONOUS:
ret = -ENOTSUPP;
break;
case PIPE_CONTROL:
case PIPE_BULK:
default:
ret = asl_urb_dequeue(whc, urb, status);
break;
}
return ret;
}
/*
* Wait for all URBs to the endpoint to be completed, then delete the
* qset.
*/
static void whc_endpoint_disable(struct usb_hcd *usb_hcd,
struct usb_host_endpoint *ep)
{
struct wusbhc *wusbhc = usb_hcd_to_wusbhc(usb_hcd);
struct whc *whc = wusbhc_to_whc(wusbhc);
struct whc_qset *qset;
qset = ep->hcpriv;
if (qset) {
ep->hcpriv = NULL;
if (usb_endpoint_xfer_bulk(&ep->desc)
|| usb_endpoint_xfer_control(&ep->desc))
asl_qset_delete(whc, qset);
else
pzl_qset_delete(whc, qset);
}
}
static void whc_endpoint_reset(struct usb_hcd *usb_hcd,
struct usb_host_endpoint *ep)
{
struct wusbhc *wusbhc = usb_hcd_to_wusbhc(usb_hcd);
struct whc *whc = wusbhc_to_whc(wusbhc);
struct whc_qset *qset;
unsigned long flags;
spin_lock_irqsave(&whc->lock, flags);
qset = ep->hcpriv;
if (qset) {
qset->remove = 1;
qset->reset = 1;
if (usb_endpoint_xfer_bulk(&ep->desc)
|| usb_endpoint_xfer_control(&ep->desc))
queue_work(whc->workqueue, &whc->async_work);
else
queue_work(whc->workqueue, &whc->periodic_work);
}
spin_unlock_irqrestore(&whc->lock, flags);
}
static struct hc_driver whc_hc_driver = {
.description = "whci-hcd",
.product_desc = "Wireless host controller",
.hcd_priv_size = sizeof(struct whc) - sizeof(struct usb_hcd),
.irq = whc_int_handler,
.flags = HCD_USB2,
.reset = whc_reset,
.start = whc_start,
.stop = whc_stop,
.get_frame_number = whc_get_frame_number,
.urb_enqueue = whc_urb_enqueue,
.urb_dequeue = whc_urb_dequeue,
.endpoint_disable = whc_endpoint_disable,
.endpoint_reset = whc_endpoint_reset,
.hub_status_data = wusbhc_rh_status_data,
.hub_control = wusbhc_rh_control,
.start_port_reset = wusbhc_rh_start_port_reset,
};
static int whc_probe(struct umc_dev *umc)
{
int ret;
struct usb_hcd *usb_hcd;
struct wusbhc *wusbhc;
struct whc *whc;
struct device *dev = &umc->dev;
usb_hcd = usb_create_hcd(&whc_hc_driver, dev, "whci");
if (usb_hcd == NULL) {
dev_err(dev, "unable to create hcd\n");
return -ENOMEM;
}
usb_hcd->wireless = 1;
usb_hcd->self.sg_tablesize = 2048; /* somewhat arbitrary */
wusbhc = usb_hcd_to_wusbhc(usb_hcd);
whc = wusbhc_to_whc(wusbhc);
whc->umc = umc;
ret = whc_init(whc);
if (ret)
goto error;
wusbhc->dev = dev;
wusbhc->uwb_rc = uwb_rc_get_by_grandpa(umc->dev.parent);
if (!wusbhc->uwb_rc) {
ret = -ENODEV;
dev_err(dev, "cannot get radio controller\n");
goto error;
}
if (whc->n_devices > USB_MAXCHILDREN) {
dev_warn(dev, "USB_MAXCHILDREN too low for WUSB adapter (%u ports)\n",
whc->n_devices);
wusbhc->ports_max = USB_MAXCHILDREN;
} else
wusbhc->ports_max = whc->n_devices;
wusbhc->mmcies_max = whc->n_mmc_ies;
wusbhc->start = whc_wusbhc_start;
wusbhc->stop = whc_wusbhc_stop;
wusbhc->mmcie_add = whc_mmcie_add;
wusbhc->mmcie_rm = whc_mmcie_rm;
wusbhc->dev_info_set = whc_dev_info_set;
wusbhc->bwa_set = whc_bwa_set;
wusbhc->set_num_dnts = whc_set_num_dnts;
wusbhc->set_ptk = whc_set_ptk;
wusbhc->set_gtk = whc_set_gtk;
ret = wusbhc_create(wusbhc);
if (ret)
goto error_wusbhc_create;
ret = usb_add_hcd(usb_hcd, whc->umc->irq, IRQF_SHARED);
if (ret) {
dev_err(dev, "cannot add HCD: %d\n", ret);
goto error_usb_add_hcd;
}
device_wakeup_enable(usb_hcd->self.controller);
ret = wusbhc_b_create(wusbhc);
if (ret) {
dev_err(dev, "WUSBHC phase B setup failed: %d\n", ret);
goto error_wusbhc_b_create;
}
whc_dbg_init(whc);
return 0;
error_wusbhc_b_create:
usb_remove_hcd(usb_hcd);
error_usb_add_hcd:
wusbhc_destroy(wusbhc);
error_wusbhc_create:
uwb_rc_put(wusbhc->uwb_rc);
error:
whc_clean_up(whc);
usb_put_hcd(usb_hcd);
return ret;
}
static void whc_remove(struct umc_dev *umc)
{
struct usb_hcd *usb_hcd = dev_get_drvdata(&umc->dev);
struct wusbhc *wusbhc = usb_hcd_to_wusbhc(usb_hcd);
struct whc *whc = wusbhc_to_whc(wusbhc);
if (usb_hcd) {
whc_dbg_clean_up(whc);
wusbhc_b_destroy(wusbhc);
usb_remove_hcd(usb_hcd);
wusbhc_destroy(wusbhc);
uwb_rc_put(wusbhc->uwb_rc);
whc_clean_up(whc);
usb_put_hcd(usb_hcd);
}
}
static struct umc_driver whci_hc_driver = {
.name = "whci-hcd",
.cap_id = UMC_CAP_ID_WHCI_WUSB_HC,
.probe = whc_probe,
.remove = whc_remove,
};
static int __init whci_hc_driver_init(void)
{
return umc_driver_register(&whci_hc_driver);
}
module_init(whci_hc_driver_init);
static void __exit whci_hc_driver_exit(void)
{
umc_driver_unregister(&whci_hc_driver);
}
module_exit(whci_hc_driver_exit);
/* PCI device ID's that we handle (so it gets loaded) */
static struct pci_device_id __used whci_hcd_id_table[] = {
{ PCI_DEVICE_CLASS(PCI_CLASS_WIRELESS_WHCI, ~0) },
{ /* empty last entry */ }
};
MODULE_DEVICE_TABLE(pci, whci_hcd_id_table);
MODULE_DESCRIPTION("WHCI Wireless USB host controller driver");
MODULE_AUTHOR("Cambridge Silicon Radio Ltd.");
MODULE_LICENSE("GPL");