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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/net/wireless/b43/phy_common.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/net/wireless/b43/phy_common.c')
-rw-r--r--kernel/drivers/net/wireless/b43/phy_common.c653
1 files changed, 653 insertions, 0 deletions
diff --git a/kernel/drivers/net/wireless/b43/phy_common.c b/kernel/drivers/net/wireless/b43/phy_common.c
new file mode 100644
index 000000000..ec2b9c577
--- /dev/null
+++ b/kernel/drivers/net/wireless/b43/phy_common.c
@@ -0,0 +1,653 @@
+/*
+
+ Broadcom B43 wireless driver
+ Common PHY routines
+
+ Copyright (c) 2005 Martin Langer <martin-langer@gmx.de>,
+ Copyright (c) 2005-2007 Stefano Brivio <stefano.brivio@polimi.it>
+ Copyright (c) 2005-2008 Michael Buesch <m@bues.ch>
+ Copyright (c) 2005, 2006 Danny van Dyk <kugelfang@gentoo.org>
+ Copyright (c) 2005, 2006 Andreas Jaggi <andreas.jaggi@waterwave.ch>
+
+ 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; see the file COPYING. If not, write to
+ the Free Software Foundation, Inc., 51 Franklin Steet, Fifth Floor,
+ Boston, MA 02110-1301, USA.
+
+*/
+
+#include "phy_common.h"
+#include "phy_g.h"
+#include "phy_a.h"
+#include "phy_n.h"
+#include "phy_lp.h"
+#include "phy_ht.h"
+#include "phy_lcn.h"
+#include "phy_ac.h"
+#include "b43.h"
+#include "main.h"
+
+
+int b43_phy_allocate(struct b43_wldev *dev)
+{
+ struct b43_phy *phy = &(dev->phy);
+ int err;
+
+ phy->ops = NULL;
+
+ switch (phy->type) {
+ case B43_PHYTYPE_G:
+#ifdef CONFIG_B43_PHY_G
+ phy->ops = &b43_phyops_g;
+#endif
+ break;
+ case B43_PHYTYPE_N:
+#ifdef CONFIG_B43_PHY_N
+ phy->ops = &b43_phyops_n;
+#endif
+ break;
+ case B43_PHYTYPE_LP:
+#ifdef CONFIG_B43_PHY_LP
+ phy->ops = &b43_phyops_lp;
+#endif
+ break;
+ case B43_PHYTYPE_HT:
+#ifdef CONFIG_B43_PHY_HT
+ phy->ops = &b43_phyops_ht;
+#endif
+ break;
+ case B43_PHYTYPE_LCN:
+#ifdef CONFIG_B43_PHY_LCN
+ phy->ops = &b43_phyops_lcn;
+#endif
+ break;
+ case B43_PHYTYPE_AC:
+#ifdef CONFIG_B43_PHY_AC
+ phy->ops = &b43_phyops_ac;
+#endif
+ break;
+ }
+ if (B43_WARN_ON(!phy->ops))
+ return -ENODEV;
+
+ err = phy->ops->allocate(dev);
+ if (err)
+ phy->ops = NULL;
+
+ return err;
+}
+
+void b43_phy_free(struct b43_wldev *dev)
+{
+ dev->phy.ops->free(dev);
+ dev->phy.ops = NULL;
+}
+
+int b43_phy_init(struct b43_wldev *dev)
+{
+ struct b43_phy *phy = &dev->phy;
+ const struct b43_phy_operations *ops = phy->ops;
+ int err;
+
+ /* During PHY init we need to use some channel. On the first init this
+ * function is called *before* b43_op_config, so our pointer is NULL.
+ */
+ if (!phy->chandef) {
+ phy->chandef = &dev->wl->hw->conf.chandef;
+ phy->channel = phy->chandef->chan->hw_value;
+ }
+
+ phy->ops->switch_analog(dev, true);
+ b43_software_rfkill(dev, false);
+
+ err = ops->init(dev);
+ if (err) {
+ b43err(dev->wl, "PHY init failed\n");
+ goto err_block_rf;
+ }
+ phy->do_full_init = false;
+
+ err = b43_switch_channel(dev, phy->channel);
+ if (err) {
+ b43err(dev->wl, "PHY init: Channel switch to default failed\n");
+ goto err_phy_exit;
+ }
+
+ return 0;
+
+err_phy_exit:
+ phy->do_full_init = true;
+ if (ops->exit)
+ ops->exit(dev);
+err_block_rf:
+ b43_software_rfkill(dev, true);
+
+ return err;
+}
+
+void b43_phy_exit(struct b43_wldev *dev)
+{
+ const struct b43_phy_operations *ops = dev->phy.ops;
+
+ b43_software_rfkill(dev, true);
+ dev->phy.do_full_init = true;
+ if (ops->exit)
+ ops->exit(dev);
+}
+
+bool b43_has_hardware_pctl(struct b43_wldev *dev)
+{
+ if (!dev->phy.hardware_power_control)
+ return false;
+ if (!dev->phy.ops->supports_hwpctl)
+ return false;
+ return dev->phy.ops->supports_hwpctl(dev);
+}
+
+void b43_radio_lock(struct b43_wldev *dev)
+{
+ u32 macctl;
+
+#if B43_DEBUG
+ B43_WARN_ON(dev->phy.radio_locked);
+ dev->phy.radio_locked = true;
+#endif
+
+ macctl = b43_read32(dev, B43_MMIO_MACCTL);
+ macctl |= B43_MACCTL_RADIOLOCK;
+ b43_write32(dev, B43_MMIO_MACCTL, macctl);
+ /* Commit the write and wait for the firmware
+ * to finish any radio register access. */
+ b43_read32(dev, B43_MMIO_MACCTL);
+ udelay(10);
+}
+
+void b43_radio_unlock(struct b43_wldev *dev)
+{
+ u32 macctl;
+
+#if B43_DEBUG
+ B43_WARN_ON(!dev->phy.radio_locked);
+ dev->phy.radio_locked = false;
+#endif
+
+ /* Commit any write */
+ b43_read16(dev, B43_MMIO_PHY_VER);
+ /* unlock */
+ macctl = b43_read32(dev, B43_MMIO_MACCTL);
+ macctl &= ~B43_MACCTL_RADIOLOCK;
+ b43_write32(dev, B43_MMIO_MACCTL, macctl);
+}
+
+void b43_phy_lock(struct b43_wldev *dev)
+{
+#if B43_DEBUG
+ B43_WARN_ON(dev->phy.phy_locked);
+ dev->phy.phy_locked = true;
+#endif
+ B43_WARN_ON(dev->dev->core_rev < 3);
+
+ if (!b43_is_mode(dev->wl, NL80211_IFTYPE_AP))
+ b43_power_saving_ctl_bits(dev, B43_PS_AWAKE);
+}
+
+void b43_phy_unlock(struct b43_wldev *dev)
+{
+#if B43_DEBUG
+ B43_WARN_ON(!dev->phy.phy_locked);
+ dev->phy.phy_locked = false;
+#endif
+ B43_WARN_ON(dev->dev->core_rev < 3);
+
+ if (!b43_is_mode(dev->wl, NL80211_IFTYPE_AP))
+ b43_power_saving_ctl_bits(dev, 0);
+}
+
+static inline void assert_mac_suspended(struct b43_wldev *dev)
+{
+ if (!B43_DEBUG)
+ return;
+ if ((b43_status(dev) >= B43_STAT_INITIALIZED) &&
+ (dev->mac_suspended <= 0)) {
+ b43dbg(dev->wl, "PHY/RADIO register access with "
+ "enabled MAC.\n");
+ dump_stack();
+ }
+}
+
+u16 b43_radio_read(struct b43_wldev *dev, u16 reg)
+{
+ assert_mac_suspended(dev);
+ dev->phy.writes_counter = 0;
+ return dev->phy.ops->radio_read(dev, reg);
+}
+
+void b43_radio_write(struct b43_wldev *dev, u16 reg, u16 value)
+{
+ assert_mac_suspended(dev);
+ if (b43_bus_host_is_pci(dev->dev) &&
+ ++dev->phy.writes_counter > B43_MAX_WRITES_IN_ROW) {
+ b43_read32(dev, B43_MMIO_MACCTL);
+ dev->phy.writes_counter = 1;
+ }
+ dev->phy.ops->radio_write(dev, reg, value);
+}
+
+void b43_radio_mask(struct b43_wldev *dev, u16 offset, u16 mask)
+{
+ b43_radio_write16(dev, offset,
+ b43_radio_read16(dev, offset) & mask);
+}
+
+void b43_radio_set(struct b43_wldev *dev, u16 offset, u16 set)
+{
+ b43_radio_write16(dev, offset,
+ b43_radio_read16(dev, offset) | set);
+}
+
+void b43_radio_maskset(struct b43_wldev *dev, u16 offset, u16 mask, u16 set)
+{
+ b43_radio_write16(dev, offset,
+ (b43_radio_read16(dev, offset) & mask) | set);
+}
+
+bool b43_radio_wait_value(struct b43_wldev *dev, u16 offset, u16 mask,
+ u16 value, int delay, int timeout)
+{
+ u16 val;
+ int i;
+
+ for (i = 0; i < timeout; i += delay) {
+ val = b43_radio_read(dev, offset);
+ if ((val & mask) == value)
+ return true;
+ udelay(delay);
+ }
+ return false;
+}
+
+u16 b43_phy_read(struct b43_wldev *dev, u16 reg)
+{
+ assert_mac_suspended(dev);
+ dev->phy.writes_counter = 0;
+
+ if (dev->phy.ops->phy_read)
+ return dev->phy.ops->phy_read(dev, reg);
+
+ b43_write16f(dev, B43_MMIO_PHY_CONTROL, reg);
+ return b43_read16(dev, B43_MMIO_PHY_DATA);
+}
+
+void b43_phy_write(struct b43_wldev *dev, u16 reg, u16 value)
+{
+ assert_mac_suspended(dev);
+ if (b43_bus_host_is_pci(dev->dev) &&
+ ++dev->phy.writes_counter > B43_MAX_WRITES_IN_ROW) {
+ b43_read16(dev, B43_MMIO_PHY_VER);
+ dev->phy.writes_counter = 1;
+ }
+
+ if (dev->phy.ops->phy_write)
+ return dev->phy.ops->phy_write(dev, reg, value);
+
+ b43_write16f(dev, B43_MMIO_PHY_CONTROL, reg);
+ b43_write16(dev, B43_MMIO_PHY_DATA, value);
+}
+
+void b43_phy_copy(struct b43_wldev *dev, u16 destreg, u16 srcreg)
+{
+ b43_phy_write(dev, destreg, b43_phy_read(dev, srcreg));
+}
+
+void b43_phy_mask(struct b43_wldev *dev, u16 offset, u16 mask)
+{
+ if (dev->phy.ops->phy_maskset) {
+ assert_mac_suspended(dev);
+ dev->phy.ops->phy_maskset(dev, offset, mask, 0);
+ } else {
+ b43_phy_write(dev, offset,
+ b43_phy_read(dev, offset) & mask);
+ }
+}
+
+void b43_phy_set(struct b43_wldev *dev, u16 offset, u16 set)
+{
+ if (dev->phy.ops->phy_maskset) {
+ assert_mac_suspended(dev);
+ dev->phy.ops->phy_maskset(dev, offset, 0xFFFF, set);
+ } else {
+ b43_phy_write(dev, offset,
+ b43_phy_read(dev, offset) | set);
+ }
+}
+
+void b43_phy_maskset(struct b43_wldev *dev, u16 offset, u16 mask, u16 set)
+{
+ if (dev->phy.ops->phy_maskset) {
+ assert_mac_suspended(dev);
+ dev->phy.ops->phy_maskset(dev, offset, mask, set);
+ } else {
+ b43_phy_write(dev, offset,
+ (b43_phy_read(dev, offset) & mask) | set);
+ }
+}
+
+void b43_phy_put_into_reset(struct b43_wldev *dev)
+{
+ u32 tmp;
+
+ switch (dev->dev->bus_type) {
+#ifdef CONFIG_B43_BCMA
+ case B43_BUS_BCMA:
+ tmp = bcma_aread32(dev->dev->bdev, BCMA_IOCTL);
+ tmp &= ~B43_BCMA_IOCTL_GMODE;
+ tmp |= B43_BCMA_IOCTL_PHY_RESET;
+ tmp |= BCMA_IOCTL_FGC;
+ bcma_awrite32(dev->dev->bdev, BCMA_IOCTL, tmp);
+ udelay(1);
+
+ tmp = bcma_aread32(dev->dev->bdev, BCMA_IOCTL);
+ tmp &= ~BCMA_IOCTL_FGC;
+ bcma_awrite32(dev->dev->bdev, BCMA_IOCTL, tmp);
+ udelay(1);
+ break;
+#endif
+#ifdef CONFIG_B43_SSB
+ case B43_BUS_SSB:
+ tmp = ssb_read32(dev->dev->sdev, SSB_TMSLOW);
+ tmp &= ~B43_TMSLOW_GMODE;
+ tmp |= B43_TMSLOW_PHYRESET;
+ tmp |= SSB_TMSLOW_FGC;
+ ssb_write32(dev->dev->sdev, SSB_TMSLOW, tmp);
+ usleep_range(1000, 2000);
+
+ tmp = ssb_read32(dev->dev->sdev, SSB_TMSLOW);
+ tmp &= ~SSB_TMSLOW_FGC;
+ ssb_write32(dev->dev->sdev, SSB_TMSLOW, tmp);
+ usleep_range(1000, 2000);
+
+ break;
+#endif
+ }
+}
+
+void b43_phy_take_out_of_reset(struct b43_wldev *dev)
+{
+ u32 tmp;
+
+ switch (dev->dev->bus_type) {
+#ifdef CONFIG_B43_BCMA
+ case B43_BUS_BCMA:
+ /* Unset reset bit (with forcing clock) */
+ tmp = bcma_aread32(dev->dev->bdev, BCMA_IOCTL);
+ tmp &= ~B43_BCMA_IOCTL_PHY_RESET;
+ tmp &= ~B43_BCMA_IOCTL_PHY_CLKEN;
+ tmp |= BCMA_IOCTL_FGC;
+ bcma_awrite32(dev->dev->bdev, BCMA_IOCTL, tmp);
+ udelay(1);
+
+ /* Do not force clock anymore */
+ tmp = bcma_aread32(dev->dev->bdev, BCMA_IOCTL);
+ tmp &= ~BCMA_IOCTL_FGC;
+ tmp |= B43_BCMA_IOCTL_PHY_CLKEN;
+ bcma_awrite32(dev->dev->bdev, BCMA_IOCTL, tmp);
+ udelay(1);
+ break;
+#endif
+#ifdef CONFIG_B43_SSB
+ case B43_BUS_SSB:
+ /* Unset reset bit (with forcing clock) */
+ tmp = ssb_read32(dev->dev->sdev, SSB_TMSLOW);
+ tmp &= ~B43_TMSLOW_PHYRESET;
+ tmp &= ~B43_TMSLOW_PHYCLKEN;
+ tmp |= SSB_TMSLOW_FGC;
+ ssb_write32(dev->dev->sdev, SSB_TMSLOW, tmp);
+ ssb_read32(dev->dev->sdev, SSB_TMSLOW); /* flush */
+ usleep_range(1000, 2000);
+
+ tmp = ssb_read32(dev->dev->sdev, SSB_TMSLOW);
+ tmp &= ~SSB_TMSLOW_FGC;
+ tmp |= B43_TMSLOW_PHYCLKEN;
+ ssb_write32(dev->dev->sdev, SSB_TMSLOW, tmp);
+ ssb_read32(dev->dev->sdev, SSB_TMSLOW); /* flush */
+ usleep_range(1000, 2000);
+ break;
+#endif
+ }
+}
+
+int b43_switch_channel(struct b43_wldev *dev, unsigned int new_channel)
+{
+ struct b43_phy *phy = &(dev->phy);
+ u16 channelcookie, savedcookie;
+ int err;
+
+ /* First we set the channel radio code to prevent the
+ * firmware from sending ghost packets.
+ */
+ channelcookie = new_channel;
+ if (b43_current_band(dev->wl) == IEEE80211_BAND_5GHZ)
+ channelcookie |= B43_SHM_SH_CHAN_5GHZ;
+ /* FIXME: set 40Mhz flag if required */
+ if (0)
+ channelcookie |= B43_SHM_SH_CHAN_40MHZ;
+ savedcookie = b43_shm_read16(dev, B43_SHM_SHARED, B43_SHM_SH_CHAN);
+ b43_shm_write16(dev, B43_SHM_SHARED, B43_SHM_SH_CHAN, channelcookie);
+
+ /* Now try to switch the PHY hardware channel. */
+ err = phy->ops->switch_channel(dev, new_channel);
+ if (err)
+ goto err_restore_cookie;
+
+ /* Wait for the radio to tune to the channel and stabilize. */
+ msleep(8);
+
+ return 0;
+
+err_restore_cookie:
+ b43_shm_write16(dev, B43_SHM_SHARED,
+ B43_SHM_SH_CHAN, savedcookie);
+
+ return err;
+}
+
+void b43_software_rfkill(struct b43_wldev *dev, bool blocked)
+{
+ struct b43_phy *phy = &dev->phy;
+
+ b43_mac_suspend(dev);
+ phy->ops->software_rfkill(dev, blocked);
+ phy->radio_on = !blocked;
+ b43_mac_enable(dev);
+}
+
+/**
+ * b43_phy_txpower_adjust_work - TX power workqueue.
+ *
+ * Workqueue for updating the TX power parameters in hardware.
+ */
+void b43_phy_txpower_adjust_work(struct work_struct *work)
+{
+ struct b43_wl *wl = container_of(work, struct b43_wl,
+ txpower_adjust_work);
+ struct b43_wldev *dev;
+
+ mutex_lock(&wl->mutex);
+ dev = wl->current_dev;
+
+ if (likely(dev && (b43_status(dev) >= B43_STAT_STARTED)))
+ dev->phy.ops->adjust_txpower(dev);
+
+ mutex_unlock(&wl->mutex);
+}
+
+void b43_phy_txpower_check(struct b43_wldev *dev, unsigned int flags)
+{
+ struct b43_phy *phy = &dev->phy;
+ unsigned long now = jiffies;
+ enum b43_txpwr_result result;
+
+ if (!(flags & B43_TXPWR_IGNORE_TIME)) {
+ /* Check if it's time for a TXpower check. */
+ if (time_before(now, phy->next_txpwr_check_time))
+ return; /* Not yet */
+ }
+ /* The next check will be needed in two seconds, or later. */
+ phy->next_txpwr_check_time = round_jiffies(now + (HZ * 2));
+
+ if ((dev->dev->board_vendor == SSB_BOARDVENDOR_BCM) &&
+ (dev->dev->board_type == SSB_BOARD_BU4306))
+ return; /* No software txpower adjustment needed */
+
+ result = phy->ops->recalc_txpower(dev, !!(flags & B43_TXPWR_IGNORE_TSSI));
+ if (result == B43_TXPWR_RES_DONE)
+ return; /* We are done. */
+ B43_WARN_ON(result != B43_TXPWR_RES_NEED_ADJUST);
+ B43_WARN_ON(phy->ops->adjust_txpower == NULL);
+
+ /* We must adjust the transmission power in hardware.
+ * Schedule b43_phy_txpower_adjust_work(). */
+ ieee80211_queue_work(dev->wl->hw, &dev->wl->txpower_adjust_work);
+}
+
+int b43_phy_shm_tssi_read(struct b43_wldev *dev, u16 shm_offset)
+{
+ const bool is_ofdm = (shm_offset != B43_SHM_SH_TSSI_CCK);
+ unsigned int a, b, c, d;
+ unsigned int average;
+ u32 tmp;
+
+ tmp = b43_shm_read32(dev, B43_SHM_SHARED, shm_offset);
+ a = tmp & 0xFF;
+ b = (tmp >> 8) & 0xFF;
+ c = (tmp >> 16) & 0xFF;
+ d = (tmp >> 24) & 0xFF;
+ if (a == 0 || a == B43_TSSI_MAX ||
+ b == 0 || b == B43_TSSI_MAX ||
+ c == 0 || c == B43_TSSI_MAX ||
+ d == 0 || d == B43_TSSI_MAX)
+ return -ENOENT;
+ /* The values are OK. Clear them. */
+ tmp = B43_TSSI_MAX | (B43_TSSI_MAX << 8) |
+ (B43_TSSI_MAX << 16) | (B43_TSSI_MAX << 24);
+ b43_shm_write32(dev, B43_SHM_SHARED, shm_offset, tmp);
+
+ if (is_ofdm) {
+ a = (a + 32) & 0x3F;
+ b = (b + 32) & 0x3F;
+ c = (c + 32) & 0x3F;
+ d = (d + 32) & 0x3F;
+ }
+
+ /* Get the average of the values with 0.5 added to each value. */
+ average = (a + b + c + d + 2) / 4;
+ if (is_ofdm) {
+ /* Adjust for CCK-boost */
+ if (b43_shm_read16(dev, B43_SHM_SHARED, B43_SHM_SH_HOSTF1)
+ & B43_HF_CCKBOOST)
+ average = (average >= 13) ? (average - 13) : 0;
+ }
+
+ return average;
+}
+
+void b43_phyop_switch_analog_generic(struct b43_wldev *dev, bool on)
+{
+ b43_write16(dev, B43_MMIO_PHY0, on ? 0 : 0xF4);
+}
+
+
+bool b43_is_40mhz(struct b43_wldev *dev)
+{
+ return dev->phy.chandef->width == NL80211_CHAN_WIDTH_40;
+}
+
+/* http://bcm-v4.sipsolutions.net/802.11/PHY/N/BmacPhyClkFgc */
+void b43_phy_force_clock(struct b43_wldev *dev, bool force)
+{
+ u32 tmp;
+
+ WARN_ON(dev->phy.type != B43_PHYTYPE_N &&
+ dev->phy.type != B43_PHYTYPE_HT &&
+ dev->phy.type != B43_PHYTYPE_AC);
+
+ switch (dev->dev->bus_type) {
+#ifdef CONFIG_B43_BCMA
+ case B43_BUS_BCMA:
+ tmp = bcma_aread32(dev->dev->bdev, BCMA_IOCTL);
+ if (force)
+ tmp |= BCMA_IOCTL_FGC;
+ else
+ tmp &= ~BCMA_IOCTL_FGC;
+ bcma_awrite32(dev->dev->bdev, BCMA_IOCTL, tmp);
+ break;
+#endif
+#ifdef CONFIG_B43_SSB
+ case B43_BUS_SSB:
+ tmp = ssb_read32(dev->dev->sdev, SSB_TMSLOW);
+ if (force)
+ tmp |= SSB_TMSLOW_FGC;
+ else
+ tmp &= ~SSB_TMSLOW_FGC;
+ ssb_write32(dev->dev->sdev, SSB_TMSLOW, tmp);
+ break;
+#endif
+ }
+}
+
+/* http://bcm-v4.sipsolutions.net/802.11/PHY/Cordic */
+struct b43_c32 b43_cordic(int theta)
+{
+ static const u32 arctg[] = {
+ 2949120, 1740967, 919879, 466945, 234379, 117304,
+ 58666, 29335, 14668, 7334, 3667, 1833,
+ 917, 458, 229, 115, 57, 29,
+ };
+ u8 i;
+ s32 tmp;
+ s8 signx = 1;
+ u32 angle = 0;
+ struct b43_c32 ret = { .i = 39797, .q = 0, };
+
+ while (theta > (180 << 16))
+ theta -= (360 << 16);
+ while (theta < -(180 << 16))
+ theta += (360 << 16);
+
+ if (theta > (90 << 16)) {
+ theta -= (180 << 16);
+ signx = -1;
+ } else if (theta < -(90 << 16)) {
+ theta += (180 << 16);
+ signx = -1;
+ }
+
+ for (i = 0; i <= 17; i++) {
+ if (theta > angle) {
+ tmp = ret.i - (ret.q >> i);
+ ret.q += ret.i >> i;
+ ret.i = tmp;
+ angle += arctg[i];
+ } else {
+ tmp = ret.i + (ret.q >> i);
+ ret.q -= ret.i >> i;
+ ret.i = tmp;
+ angle -= arctg[i];
+ }
+ }
+
+ ret.i *= signx;
+ ret.q *= signx;
+
+ return ret;
+}