litmus-rt.git - The LITMUS^RT kernel.

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author	Johannes Berg <johannes@sipsolutions.net>	2008-02-25 10:27:46 -0500
committer	John W. Linville <linville@tuxdriver.com>	2008-03-06 15:30:46 -0500
commit	d0709a65181beb787ef3f58cfe45536a2bb254c8 (patch)
tree	29e5f36583b0e0a3f11b291347e57672eab41dad /net/mac80211/debugfs_sta.h
parent	5cf121c3cdb955583bf0c5d28c992b7968a4aa1a (diff)

mac80211: RCU-ify STA info structure access

This makes access to the STA hash table/list use RCU to protect against freeing of items. However, it's not a true RCU, the copy step is missing: whenever somebody changes a STA item it is simply updated. This is an existing race condition that is now somewhat understandable. This patch also fixes the race key freeing vs. STA destruction by making sure that sta_info_destroy() is always called under RTNL and frees the key. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>

Diffstat (limited to 'net/mac80211/debugfs_sta.h')

-rw-r--r--

net/mac80211/debugfs_sta.h

1 files changed, 2 insertions, 0 deletions


diff --git a/net/mac80211/debugfs_sta.h b/net/mac80211/debugfs_sta.h index 574a1cd54b96..8b608903259f 100644 --- a/net/mac80211/debugfs_sta.h +++ b/net/mac80211/debugfs_sta.h
@@ -1,6 +1,8 @@
1	#ifndef __MAC80211_DEBUGFS_STA_H	1	#ifndef __MAC80211_DEBUGFS_STA_H
2	#define __MAC80211_DEBUGFS_STA_H	2	#define __MAC80211_DEBUGFS_STA_H
3		3
		4	#include "sta_info.h"
		5
4	#ifdef CONFIG_MAC80211_DEBUGFS	6	#ifdef CONFIG_MAC80211_DEBUGFS
5	void ieee80211_sta_debugfs_add(struct sta_info *sta);	7	void ieee80211_sta_debugfs_add(struct sta_info *sta);
6	void ieee80211_sta_debugfs_remove(struct sta_info *sta);	8	void ieee80211_sta_debugfs_remove(struct sta_info *sta);

/* * ISP1704 USB Charger Detection driver * * Copyright (C) 2010 Nokia Corporation * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/err.h> #include <linux/init.h> #include <linux/types.h> #include <linux/device.h> #include <linux/sysfs.h> #include <linux/platform_device.h> #include <linux/power_supply.h> #include <linux/delay.h> #include <linux/usb/otg.h> #include <linux/usb/ulpi.h> #include <linux/usb/ch9.h> #include <linux/usb/gadget.h> /* Vendor specific Power Control register */ #define ISP1704_PWR_CTRL 0x3d #define ISP1704_PWR_CTRL_SWCTRL (1 << 0) #define ISP1704_PWR_CTRL_DET_COMP (1 << 1) #define ISP1704_PWR_CTRL_BVALID_RISE (1 << 2) #define ISP1704_PWR_CTRL_BVALID_FALL (1 << 3) #define ISP1704_PWR_CTRL_DP_WKPU_EN (1 << 4) #define ISP1704_PWR_CTRL_VDAT_DET (1 << 5) #define ISP1704_PWR_CTRL_DPVSRC_EN (1 << 6) #define ISP1704_PWR_CTRL_HWDETECT (1 << 7) #define NXP_VENDOR_ID 0x04cc static u16 isp170x_id[] = { 0x1704, 0x1707, }; struct isp1704_charger { struct device *dev; struct power_supply psy; struct otg_transceiver *otg; struct notifier_block nb; struct work_struct work; /* properties */ char model[8]; unsigned present:1; unsigned online:1; unsigned current_max; /* temp storage variables */ unsigned long event; unsigned max_power; }; /* * Determine is the charging port DCP (dedicated charger) or CDP (Host/HUB * chargers). * * REVISIT: The method is defined in Battery Charging Specification and is * applicable to any ULPI transceiver. Nothing isp170x specific here. */ static inline int isp1704_charger_type(struct isp1704_charger *isp) { u8 reg; u8 func_ctrl; u8 otg_ctrl; int type = POWER_SUPPLY_TYPE_USB_DCP; func_ctrl = otg_io_read(isp->otg, ULPI_FUNC_CTRL); otg_ctrl = otg_io_read(isp->otg, ULPI_OTG_CTRL); /* disable pulldowns */ reg = ULPI_OTG_CTRL_DM_PULLDOWN | ULPI_OTG_CTRL_DP_PULLDOWN; otg_io_write(isp->otg, ULPI_CLR(ULPI_OTG_CTRL), reg); /* full speed */ otg_io_write(isp->otg, ULPI_CLR(ULPI_FUNC_CTRL), ULPI_FUNC_CTRL_XCVRSEL_MASK); otg_io_write(isp->otg, ULPI_SET(ULPI_FUNC_CTRL), ULPI_FUNC_CTRL_FULL_SPEED); /* Enable strong pull-up on DP (1.5K) and reset */ reg = ULPI_FUNC_CTRL_TERMSELECT | ULPI_FUNC_CTRL_RESET; otg_io_write(isp->otg, ULPI_SET(ULPI_FUNC_CTRL), reg); usleep_range(1000, 2000); reg = otg_io_read(isp->otg, ULPI_DEBUG); if ((reg & 3) != 3) type = POWER_SUPPLY_TYPE_USB_CDP; /* recover original state */ otg_io_write(isp->otg, ULPI_FUNC_CTRL, func_ctrl); otg_io_write(isp->otg, ULPI_OTG_CTRL, otg_ctrl); return type; } /* * ISP1704 detects PS/2 adapters as charger. To make sure the detected charger * is actually a dedicated charger, the following steps need to be taken. */ static inline int isp1704_charger_verify(struct isp1704_charger *isp) { int ret = 0; u8 r; /* Reset the transceiver */ r = otg_io_read(isp->otg, ULPI_FUNC_CTRL); r |= ULPI_FUNC_CTRL_RESET; otg_io_write(isp->otg, ULPI_FUNC_CTRL, r); usleep_range(1000, 2000); /* Set normal mode */ r &= ~(ULPI_FUNC_CTRL_RESET | ULPI_FUNC_CTRL_OPMODE_MASK); otg_io_write(isp->otg, ULPI_FUNC_CTRL, r); /* Clear the DP and DM pull-down bits */ r = ULPI_OTG_CTRL_DP_PULLDOWN | ULPI_OTG_CTRL_DM_PULLDOWN; otg_io_write(isp->otg, ULPI_CLR(ULPI_OTG_CTRL), r); /* Enable strong pull-up on DP (1.5K) and reset */ r = ULPI_FUNC_CTRL_TERMSELECT | ULPI_FUNC_CTRL_RESET; otg_io_write(isp->otg, ULPI_SET(ULPI_FUNC_CTRL), r); usleep_range(1000, 2000); /* Read the line state */ if (!otg_io_read(isp->otg, ULPI_DEBUG)) { /* Disable strong pull-up on DP (1.5K) */ otg_io_write(isp->otg, ULPI_CLR(ULPI_FUNC_CTRL), ULPI_FUNC_CTRL_TERMSELECT); return 1; } /* Is it a charger or PS/2 connection */ /* Enable weak pull-up resistor on DP */ otg_io_write(isp->otg, ULPI_SET(ISP1704_PWR_CTRL), ISP1704_PWR_CTRL_DP_WKPU_EN); /* Disable strong pull-up on DP (1.5K) */ otg_io_write(isp->otg, ULPI_CLR(ULPI_FUNC_CTRL), ULPI_FUNC_CTRL_TERMSELECT); /* Enable weak pull-down resistor on DM */ otg_io_write(isp->otg, ULPI_SET(ULPI_OTG_CTRL), ULPI_OTG_CTRL_DM_PULLDOWN); /* It's a charger if the line states are clear */ if (!(otg_io_read(isp->otg, ULPI_DEBUG))) ret = 1; /* Disable weak pull-up resistor on DP */ otg_io_write(isp->otg, ULPI_CLR(ISP1704_PWR_CTRL), ISP1704_PWR_CTRL_DP_WKPU_EN); return ret; } static inline int isp1704_charger_detect(struct isp1704_charger *isp) { unsigned long timeout; u8 pwr_ctrl; int ret = 0; pwr_ctrl = otg_io_read(isp->otg, ISP1704_PWR_CTRL); /* set SW control bit in PWR_CTRL register */ otg_io_write(isp->otg, ISP1704_PWR_CTRL, ISP1704_PWR_CTRL_SWCTRL); /* enable manual charger detection */ otg_io_write(isp->otg, ULPI_SET(ISP1704_PWR_CTRL), ISP1704_PWR_CTRL_SWCTRL | ISP1704_PWR_CTRL_DPVSRC_EN); usleep_range(1000, 2000); timeout = jiffies + msecs_to_jiffies(300); do { /* Check if there is a charger */ if (otg_io_read(isp->otg, ISP1704_PWR_CTRL) & ISP1704_PWR_CTRL_VDAT_DET) { ret = isp1704_charger_verify(isp); break; } } while (!time_after(jiffies, timeout) && isp->online); /* recover original state */ otg_io_write(isp->otg, ISP1704_PWR_CTRL, pwr_ctrl); return ret; } static void isp1704_charger_work(struct work_struct *data) { int detect; unsigned long event; unsigned power; struct isp1704_charger *isp = container_of(data, struct isp1704_charger, work); static DEFINE_MUTEX(lock); event = isp->event; power = isp->max_power; mutex_lock(&lock); switch (event) { case USB_EVENT_VBUS: isp->online = true; /* detect charger */ detect = isp1704_charger_detect(isp); if (detect) { isp->present = detect; isp->psy.type = isp1704_charger_type(isp); } switch (isp->psy.type) { case POWER_SUPPLY_TYPE_USB_DCP: isp->current_max = 1800; break; case POWER_SUPPLY_TYPE_USB_CDP: /* * Only 500mA here or high speed chirp * handshaking may break */ isp->current_max = 500; /* FALLTHROUGH */ case POWER_SUPPLY_TYPE_USB: default: /* enable data pullups */ if (isp->otg->gadget) usb_gadget_connect(isp->otg->gadget); } break; case USB_EVENT_NONE: isp->online = false; isp->current_max = 0; isp->present = 0; isp->current_max = 0; isp->psy.type = POWER_SUPPLY_TYPE_USB; /* * Disable data pullups. We need to prevent the controller from * enumerating. * * FIXME: This is here to allow charger detection with Host/HUB * chargers. The pullups may be enabled elsewhere, so this can * not be the final solution. */ if (isp->otg->gadget) usb_gadget_disconnect(isp->otg->gadget); break; case USB_EVENT_ENUMERATED: if (isp->present) isp->current_max = 1800; else isp->current_max = power; break; default: goto out; } power_supply_changed(&isp->psy); out: mutex_unlock(&lock); } static int isp1704_notifier_call(struct notifier_block *nb, unsigned long event, void *power) { struct isp1704_charger *isp = container_of(nb, struct isp1704_charger, nb); isp->event = event; if (power) isp->max_power = *((unsigned *)power); schedule_work(&isp->work); return NOTIFY_OK; } static int isp1704_charger_get_property(struct power_supply *psy, enum power_supply_property psp, union power_supply_propval *val) { struct isp1704_charger *isp = container_of(psy, struct isp1704_charger, psy); switch (psp) { case POWER_SUPPLY_PROP_PRESENT: val->intval = isp->present; break; case POWER_SUPPLY_PROP_ONLINE: val->intval = isp->online; break; case POWER_SUPPLY_PROP_CURRENT_MAX: val->intval = isp->current_max; break; case POWER_SUPPLY_PROP_MODEL_NAME: val->strval = isp->model; break; case POWER_SUPPLY_PROP_MANUFACTURER: val->strval = "NXP"; break; default: return -EINVAL; } return 0; } static enum power_supply_property power_props[] = { POWER_SUPPLY_PROP_PRESENT, POWER_SUPPLY_PROP_ONLINE, POWER_SUPPLY_PROP_CURRENT_MAX, POWER_SUPPLY_PROP_MODEL_NAME, POWER_SUPPLY_PROP_MANUFACTURER, }; static inline int isp1704_test_ulpi(struct isp1704_charger *isp) { int vendor; int product; int i; int ret = -ENODEV; /* Test ULPI interface */ ret = otg_io_write(isp->otg, ULPI_SCRATCH, 0xaa); if (ret < 0) return ret; ret = otg_io_read(isp->otg, ULPI_SCRATCH); if (ret < 0) return ret; if (ret != 0xaa) return -ENODEV; /* Verify the product and vendor id matches */ vendor = otg_io_read(isp->otg, ULPI_VENDOR_ID_LOW); vendor |= otg_io_read(isp->otg, ULPI_VENDOR_ID_HIGH) << 8; if (vendor != NXP_VENDOR_ID) return -ENODEV; product = otg_io_read(isp->otg, ULPI_PRODUCT_ID_LOW); product |= otg_io_read(isp->otg, ULPI_PRODUCT_ID_HIGH) << 8; for (i = 0; i < ARRAY_SIZE(isp170x_id); i++) { if (product == isp170x_id[i]) { sprintf(isp->model, "isp%x", product); return product; } } dev_err(isp->dev, "product id %x not matching known ids", product); return -ENODEV; } static int __devinit isp1704_charger_probe(struct platform_device *pdev) { struct isp1704_charger *isp; int ret = -ENODEV; isp = kzalloc(sizeof *isp, GFP_KERNEL); if (!isp) return -ENOMEM; isp->otg = otg_get_transceiver(); if (!isp->otg) goto fail0; isp->dev = &pdev->dev; platform_set_drvdata(pdev, isp); ret = isp1704_test_ulpi(isp); if (ret < 0) goto fail1; isp->psy.name = "isp1704"; isp->psy.type = POWER_SUPPLY_TYPE_USB; isp->psy.properties = power_props; isp->psy.num_properties = ARRAY_SIZE(power_props); isp->psy.get_property = isp1704_charger_get_property; ret = power_supply_register(isp->dev, &isp->psy); if (ret) goto fail1; /* * REVISIT: using work in order to allow the otg notifications to be * made atomically in the future. */ INIT_WORK(&isp->work, isp1704_charger_work); isp->nb.notifier_call = isp1704_notifier_call; ret = otg_register_notifier(isp->otg, &isp->nb); if (ret) goto fail2; dev_info(isp->dev, "registered with product id %s\n", isp->model); /* * Taking over the D+ pullup. * * FIXME: The device will be disconnected if it was already * enumerated. The charger driver should be always loaded before any * gadget is loaded. */ if (isp->otg->gadget) usb_gadget_disconnect(isp->otg->gadget); /* Detect charger if VBUS is valid (the cable was already plugged). */ ret = otg_io_read(isp->otg, ULPI_USB_INT_STS); if ((ret & ULPI_INT_VBUS_VALID) && !isp->otg->default_a) { isp->event = USB_EVENT_VBUS; schedule_work(&isp->work); } return 0; fail2: power_supply_unregister(&isp->psy); fail1: otg_put_transceiver(isp->otg); fail0: kfree(isp); dev_err(&pdev->dev, "failed to register isp1704 with error %d\n", ret); return ret; } static int __devexit isp1704_charger_remove(struct platform_device *pdev) { struct isp1704_charger *isp = platform_get_drvdata(pdev); otg_unregister_notifier(isp->otg, &isp->nb); power_supply_unregister(&isp->psy); otg_put_transceiver(isp->otg); kfree(isp); return 0; } static struct platform_driver isp1704_charger_driver = { .driver = { .name = "isp1704_charger", }, .probe = isp1704_charger_probe, .remove = __devexit_p(isp1704_charger_remove), }; static int __init isp1704_charger_init(void) { return platform_driver_register(&isp1704_charger_driver); } module_init(isp1704_charger_init); static void __exit isp1704_charger_exit(void) { platform_driver_unregister(&isp1704_charger_driver); } module_exit(isp1704_charger_exit); MODULE_ALIAS("platform:isp1704_charger"); MODULE_AUTHOR("Nokia Corporation"); MODULE_DESCRIPTION("ISP170x USB Charger driver"); MODULE_LICENSE("GPL");


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