On Tue, Jun 15, 2010 at 10:10 AM, Richard Cochran
[off-list ref] wrote:

This patch adds a driver for the hardware time stamping unit found on the
IXP465. Only the basic clock operations are implemented.

Signed-off-by: Richard Cochran <redacted>

Hi Richard,

Comments below...

---
=A0arch/arm/mach-ixp4xx/include/mach/ixp46x_ts.h | =A0 67 +++++++
=A0drivers/net/arm/ixp4xx_eth.c =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0| =A01=

94 +++++++++++++++++++++

=A0drivers/ptp/Kconfig =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =

=A0 | =A0 13 ++

=A0drivers/ptp/Makefile =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =

=A0| =A0 =A01 +

=A0drivers/ptp/ptp_ixp46x.c =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0| =

=A0231 +++++++++++++++++++++++++

h-ixp4xx/include/mach/ixp46x_ts.h

fy

+ * =A0it under the terms of the GNU General Public License as published =

by

+ * =A0the Free Software Foundation; either version 2 of the License, or
+ * =A0(at your option) any later version.
+ *
+ * =A0This program is distributed in the hope that it will be useful,
+ * =A0but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * =A0MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. =A0See the
+ * =A0GNU General Public License for more details.
+ *
+ * =A0You should have received a copy of the GNU General Public License
+ * =A0along with this program; if not, write to the Free Software
+ * =A0Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef _IXP46X_TS_H_
+#define _IXP46X_TS_H_
+
+#define DEFAULT_ADDEND 0xF0000029
+#define TICKS_NS_SHIFT 4
+
+struct ixp46x_channel_ctl {
+ =A0 =A0 =A0 u32 Ch_Control; /* 0x40 Time Synchronization Channel Contro=

l */

+ =A0 =A0 =A0 u32 Ch_Event; =A0 /* 0x44 Time Synchronization Channel Even=

t */

+ =A0 =A0 =A0 u32 TxSnapLo; =A0 /* 0x48 Transmit Snapshot Low Register */
+ =A0 =A0 =A0 u32 TxSnapHi; =A0 /* 0x4C Transmit Snapshot High Register *=

/

+ =A0 =A0 =A0 u32 RxSnapLo; =A0 /* 0x50 Receive Snapshot Low Register */
+ =A0 =A0 =A0 u32 RxSnapHi; =A0 /* 0x54 Receive Snapshot High Register */
+ =A0 =A0 =A0 u32 SrcUUIDLo; =A0/* 0x58 Source UUID0 Low Register */
+ =A0 =A0 =A0 u32 SrcUUIDHi; =A0/* 0x5C Sequence Identifier/Source UUID0 =

High */

+};

Nitpick.  We use all lower case names for structures in Linux.

+
+struct ixp46x_ts_regs {
+ =A0 =A0 =A0 u32 Control; =A0 =A0 /* 0x00 Time Sync Control Register */
+ =A0 =A0 =A0 u32 Event; =A0 =A0 =A0 /* 0x04 Time Sync Event Register */
+ =A0 =A0 =A0 u32 Addend; =A0 =A0 =A0/* 0x08 Time Sync Addend Register */
+ =A0 =A0 =A0 u32 Accum; =A0 =A0 =A0 /* 0x0C Time Sync Accumulator Regist=

er */

+ =A0 =A0 =A0 u32 Test; =A0 =A0 =A0 =A0/* 0x10 Time Sync Test Register */
+ =A0 =A0 =A0 u32 Unused; =A0 =A0 =A0/* 0x14 */
+ =A0 =A0 =A0 u32 RSysTime_Lo; /* 0x18 RawSystemTime_Low Register */
+ =A0 =A0 =A0 u32 RSysTimeHi; =A0/* 0x1C RawSystemTime_High Register */
+ =A0 =A0 =A0 u32 SysTimeLo; =A0 /* 0x20 SystemTime_Low Register */
+ =A0 =A0 =A0 u32 SysTimeHi; =A0 /* 0x24 SystemTime_High Register */
+ =A0 =A0 =A0 u32 TrgtLo; =A0 =A0 =A0/* 0x28 TargetTime_Low Register */
+ =A0 =A0 =A0 u32 TrgtHi; =A0 =A0 =A0/* 0x2C TargetTime_High Register */
+ =A0 =A0 =A0 u32 ASMSLo; =A0 =A0 =A0/* 0x30 Auxiliary Slave Mode Snapsho=

t Low =A0*/

+ =A0 =A0 =A0 u32 ASMSHi; =A0 =A0 =A0/* 0x34 Auxiliary Slave Mode Snapsho=

t High */

+ =A0 =A0 =A0 u32 AMMSLo; =A0 =A0 =A0/* 0x38 Auxiliary Master Mode Snapsh=

ot Low */

+ =A0 =A0 =A0 u32 AMMSHi; =A0 =A0 =A0/* 0x3C Auxiliary Master Mode Snapsh=

ot High */

 */

er));

+
+ =A0 =A0 =A0 if (PTP_CLASS_V1_IPV4 =3D=3D type) {
+
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 id =3D (u16 *)(data + 42 + 30);
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 hi =3D (u16 *)(data + 42 + 22);
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 lo =3D data + 42 + 24;
+
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 return (uid_hi =3D=3D *hi &&
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 0 =3D=3D memcmp(&uid_lo, lo=

, sizeof(uid_lo)) &&

+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 seq =3D=3D *id);
+ =A0 =A0 =A0 }
+
+ =A0 =A0 =A0 return 0;
+}
+
+static void do_rx_timestamp(struct port *port, struct sk_buff *skb)
+{
+ =A0 =A0 =A0 struct skb_shared_hwtstamps *shhwtstamps;
+ =A0 =A0 =A0 struct ixp46x_ts_regs *regs;
+ =A0 =A0 =A0 u64 ns;
+ =A0 =A0 =A0 u32 ch, hi, lo, val;
+ =A0 =A0 =A0 u16 uid, seq;
+
+ =A0 =A0 =A0 if (!port->hwts_rx_en)
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 return;
+
+ =A0 =A0 =A0 ch =3D PORT2CHANNEL(port);
+
+ =A0 =A0 =A0 regs =3D (struct ixp46x_ts_regs __iomem *) IXP4XX_TIMESYNC_=

BASE_VIRT;

+
+ =A0 =A0 =A0 val =3D __raw_readl(&regs->channel[ch].Ch_Event);
+
+ =A0 =A0 =A0 if (!(val & RX_SNAPSHOT_LOCKED))
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 return;
+
+ =A0 =A0 =A0 lo =3D __raw_readl(&regs->channel[ch].SrcUUIDLo);
+ =A0 =A0 =A0 hi =3D __raw_readl(&regs->channel[ch].SrcUUIDHi);
+
+ =A0 =A0 =A0 uid =3D hi & 0xffff;
+ =A0 =A0 =A0 seq =3D (hi >> 16) & 0xffff;
+
+ =A0 =A0 =A0 if (!match(skb, htons(uid), htonl(lo), htons(seq)))
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 goto out;
+
+ =A0 =A0 =A0 lo =3D __raw_readl(&regs->channel[ch].RxSnapLo);
+ =A0 =A0 =A0 hi =3D __raw_readl(&regs->channel[ch].RxSnapHi);
+ =A0 =A0 =A0 ns =3D ((u64) hi) << 32;
+ =A0 =A0 =A0 ns |=3D lo;
+ =A0 =A0 =A0 ns <<=3D TICKS_NS_SHIFT;
+
+ =A0 =A0 =A0 shhwtstamps =3D skb_hwtstamps(skb);
+ =A0 =A0 =A0 memset(shhwtstamps, 0, sizeof(*shhwtstamps));
+ =A0 =A0 =A0 shhwtstamps->hwtstamp =3D ns_to_ktime(ns);
+out:
+ =A0 =A0 =A0 __raw_writel(RX_SNAPSHOT_LOCKED, &regs->channel[ch].Ch_Even=

t);

+}
+
+static void do_tx_timestamp(struct port *port, struct sk_buff *skb)
+{
+#ifdef __ARMEB__
+ =A0 =A0 =A0 struct skb_shared_hwtstamps shhwtstamps;
+ =A0 =A0 =A0 struct ixp46x_ts_regs *regs;
+ =A0 =A0 =A0 union skb_shared_tx *shtx;
+ =A0 =A0 =A0 u64 ns;
+ =A0 =A0 =A0 u32 ch, cnt, hi, lo, val;
+
+ =A0 =A0 =A0 shtx =3D skb_tx(skb);
+
+ =A0 =A0 =A0 if (!shtx->in_progress)
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 return;
+
+ =A0 =A0 =A0 ch =3D PORT2CHANNEL(port);
+
+ =A0 =A0 =A0 regs =3D (struct ixp46x_ts_regs __iomem *) IXP4XX_TIMESYNC_=

BASE_VIRT;

+
+ =A0 =A0 =A0 /*
+ =A0 =A0 =A0 =A0* This really stinks, but we have to poll for the Tx tim=

e stamp.

+ =A0 =A0 =A0 =A0* Usually, the time stamp is ready after 4 to 6 microsec=

onds.

+ =A0 =A0 =A0 =A0*/
+ =A0 =A0 =A0 for (cnt =3D 0; cnt < 100; cnt++) {
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 val =3D __raw_readl(&regs->channel[ch].Ch_E=

vent);

+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 if (val & TX_SNAPSHOT_LOCKED)
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 break;
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 udelay(1);

You want to get stuff as fast as possible, but there is a udelay()
that just chews up CPU time.  Would cpu_relax() be sufficient with a
time-based exit condition in the loop?

+ =A0 =A0 =A0 }
+ =A0 =A0 =A0 if (!(val & TX_SNAPSHOT_LOCKED)) {
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 shtx->in_progress =3D 0;
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 return;
+ =A0 =A0 =A0 }
+
+ =A0 =A0 =A0 lo =3D __raw_readl(&regs->channel[ch].TxSnapLo);
+ =A0 =A0 =A0 hi =3D __raw_readl(&regs->channel[ch].TxSnapHi);
+ =A0 =A0 =A0 ns =3D ((u64) hi) << 32;
+ =A0 =A0 =A0 ns |=3D lo;
+ =A0 =A0 =A0 ns <<=3D TICKS_NS_SHIFT;
+
+ =A0 =A0 =A0 memset(&shhwtstamps, 0, sizeof(shhwtstamps));
+ =A0 =A0 =A0 shhwtstamps.hwtstamp =3D ns_to_ktime(ns);
+ =A0 =A0 =A0 skb_tstamp_tx(skb, &shhwtstamps);
+
+ =A0 =A0 =A0 __raw_writel(TX_SNAPSHOT_LOCKED, &regs->channel[ch].Ch_Even=

t);

+#endif
+}
+
+static int hwtstamp_ioctl(struct net_device *netdev, struct ifreq *ifr, =

int cmd)

+{
+ =A0 =A0 =A0 struct hwtstamp_config cfg;
+ =A0 =A0 =A0 struct ixp46x_ts_regs *regs;
+ =A0 =A0 =A0 struct port *port =3D netdev_priv(netdev);
+ =A0 =A0 =A0 int ch;
+
+ =A0 =A0 =A0 if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 return -EFAULT;
+
+ =A0 =A0 =A0 if (cfg.flags) /* reserved for future extensions */
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 return -EINVAL;
+
+ =A0 =A0 =A0 ch =3D PORT2CHANNEL(port);
+ =A0 =A0 =A0 regs =3D (struct ixp46x_ts_regs __iomem *) IXP4XX_TIMESYNC_=

BASE_VIRT;

+
+ =A0 =A0 =A0 switch (cfg.tx_type) {
+ =A0 =A0 =A0 case HWTSTAMP_TX_OFF:
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 port->hwts_tx_en =3D 0;
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 break;
+ =A0 =A0 =A0 case HWTSTAMP_TX_ON:
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 port->hwts_tx_en =3D 1;
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 break;
+ =A0 =A0 =A0 default:
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 return -ERANGE;
+ =A0 =A0 =A0 }
+
+ =A0 =A0 =A0 switch (cfg.rx_filter) {
+ =A0 =A0 =A0 case HWTSTAMP_FILTER_NONE:
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 port->hwts_rx_en =3D 0;
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 break;
+ =A0 =A0 =A0 case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 port->hwts_rx_en =3D PTP_SLAVE_MODE;
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 __raw_writel(0, &regs->channel[ch].Ch_Contr=

ol);

+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 break;
+ =A0 =A0 =A0 case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 port->hwts_rx_en =3D PTP_MASTER_MODE;
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 __raw_writel(MASTER_MODE, &regs->channel[ch=

].Ch_Control);

+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 break;
+ =A0 =A0 =A0 default:
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 return -ERANGE;
+ =A0 =A0 =A0 }
+
+ =A0 =A0 =A0 /* Clear out any old time stamps. */
+ =A0 =A0 =A0 __raw_writel(TX_SNAPSHOT_LOCKED | RX_SNAPSHOT_LOCKED,
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0&regs->channel[ch].Ch_Event);
+
+ =A0 =A0 =A0 return copy_to_user(ifr->ifr_data, &cfg, sizeof(cfg)) ? -EF=

AULT : 0;

+}

=A0static int ixp4xx_mdio_cmd(struct mii_bus *bus, int phy_id, int locati=

on,

get)

=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0debug_pkt(dev, "eth_poll", skb->data, skb-=
len);

+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 do_rx_timestamp(port, skb);
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0skb->protocol =3D eth_type_trans(skb, dev)=

;

evice *dev)

device *dev)

evice *dev)

freq *req, int cmd)

device *pdev)

 module

=A0 =A0 =A0 =A0 =A0will be called gianfar_ptp.

+config PTP_1588_CLOCK_IXP46X
+ =A0 =A0 =A0 tristate "Intel IXP46x as PTP clock"
+ =A0 =A0 =A0 depends on PTP_1588_CLOCK
+ =A0 =A0 =A0 depends on IXP4XX_ETH
+ =A0 =A0 =A0 help
+ =A0 =A0 =A0 =A0 This driver adds support for using the IXP46X as a PTP
+ =A0 =A0 =A0 =A0 clock. This clock is only useful if your PTP programs a=

re

+ =A0 =A0 =A0 =A0 getting hardware time stamps on the PTP Ethernet packet=

s

+ =A0 =A0 =A0 =A0 using the SO_TIMESTAMPING API.
+
+ =A0 =A0 =A0 =A0 To compile this driver as a module, choose M here: the =

module

fy

+ * =A0it under the terms of the GNU General Public License as published =

by

+ * =A0the Free Software Foundation; either version 2 of the License, or
+ * =A0(at your option) any later version.
+ *
+ * =A0This program is distributed in the hope that it will be useful,
+ * =A0but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * =A0MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. =A0See the
+ * =A0GNU General Public License for more details.
+ *
+ * =A0You should have received a copy of the GNU General Public License
+ * =A0along with this program; if not, write to the Free Software
+ * =A0Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+#include <linux/ptp_clock_kernel.h>
+#include <mach/ixp46x_ts.h>
+
+DEFINE_SPINLOCK(register_lock);
+
+/*
+ * Register access functions
+ */
+
+static inline u32 ixp_read(volatile unsigned __iomem *addr)
+{
+ =A0 =A0 =A0 u32 val;
+ =A0 =A0 =A0 val =3D __raw_readl(addr);
+ =A0 =A0 =A0 return val;
+}

return __raw_readl(addr) perhaps?

+
+static inline void ixp_write(volatile unsigned __iomem *addr, u32 val)
+{
+ =A0 =A0 =A0 __raw_writel(val, addr);
+}
+
+static u64 sys_time_read(struct ixp46x_ts_regs *regs)
+{
+ =A0 =A0 =A0 u64 ns;
+ =A0 =A0 =A0 u32 lo, hi;
+
+ =A0 =A0 =A0 lo =3D ixp_read(&regs->SysTimeLo);
+ =A0 =A0 =A0 hi =3D ixp_read(&regs->SysTimeHi);
+
+ =A0 =A0 =A0 ns =3D ((u64) hi) << 32;
+ =A0 =A0 =A0 ns |=3D lo;
+ =A0 =A0 =A0 ns <<=3D TICKS_NS_SHIFT;
+
+ =A0 =A0 =A0 return ns;
+}
+
+static void sys_time_write(struct ixp46x_ts_regs *regs, u64 ns)

Should use the ptp_ixp_ prefix on these functions too.

+{
+ =A0 =A0 =A0 u32 hi, lo;
+
+ =A0 =A0 =A0 ns >>=3D TICKS_NS_SHIFT;
+ =A0 =A0 =A0 hi =3D ns >> 32;
+ =A0 =A0 =A0 lo =3D ns & 0xffffffff;
+
+ =A0 =A0 =A0 ixp_write(&regs->SysTimeLo, lo);
+ =A0 =A0 =A0 ixp_write(&regs->SysTimeHi, hi);
+}
+
+/*
+ * PTP clock operations
+ */
+
+static int ptp_ixp_adjfreq(void *priv, s32 ppb)
+{
+ =A0 =A0 =A0 u64 adj;
+ =A0 =A0 =A0 u32 diff, addend;
+ =A0 =A0 =A0 int neg_adj =3D 0;
+ =A0 =A0 =A0 struct ixp46x_ts_regs *regs =3D priv;
+
+ =A0 =A0 =A0 if (!ppb)
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 return 0;
+
+ =A0 =A0 =A0 if (ppb < 0) {
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 neg_adj =3D 1;
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 ppb =3D -ppb;
+ =A0 =A0 =A0 }
+ =A0 =A0 =A0 addend =3D DEFAULT_ADDEND;
+ =A0 =A0 =A0 adj =3D addend;
+ =A0 =A0 =A0 adj *=3D ppb;
+ =A0 =A0 =A0 diff =3D div_u64(adj, 1000000000ULL);
+
+ =A0 =A0 =A0 addend =3D neg_adj ? addend - diff : addend + diff;
+
+ =A0 =A0 =A0 ixp_write(&regs->Addend, addend);
+
+ =A0 =A0 =A0 return 0;
+}
+
+static int ptp_ixp_adjtime(void *priv, struct timespec *ts)
+{
+ =A0 =A0 =A0 s64 delta, now;
+ =A0 =A0 =A0 unsigned long flags;
+ =A0 =A0 =A0 struct ixp46x_ts_regs *regs =3D priv;
+
+ =A0 =A0 =A0 delta =3D 1000000000LL * ts->tv_sec;
+ =A0 =A0 =A0 delta +=3D ts->tv_nsec;
+
+ =A0 =A0 =A0 spin_lock_irqsave(&register_lock, flags);
+
+ =A0 =A0 =A0 now =3D sys_time_read(regs);
+ =A0 =A0 =A0 now +=3D delta;
+ =A0 =A0 =A0 sys_time_write(regs, now);
+
+ =A0 =A0 =A0 spin_unlock_irqrestore(&register_lock, flags);
+
+ =A0 =A0 =A0 return 0;
+}
+
+static int ptp_ixp_gettime(void *priv, struct timespec *ts)
+{
+ =A0 =A0 =A0 u64 ns;
+ =A0 =A0 =A0 u32 remainder;
+ =A0 =A0 =A0 unsigned long flags;
+ =A0 =A0 =A0 struct ixp46x_ts_regs *regs =3D priv;
+
+ =A0 =A0 =A0 spin_lock_irqsave(&register_lock, flags);
+
+ =A0 =A0 =A0 ns =3D sys_time_read(regs);
+
+ =A0 =A0 =A0 spin_unlock_irqrestore(&register_lock, flags);
+
+ =A0 =A0 =A0 ts->tv_sec =3D div_u64_rem(ns, 1000000000, &remainder);
+ =A0 =A0 =A0 ts->tv_nsec =3D remainder;
+ =A0 =A0 =A0 return 0;
+}
+
+static int ptp_ixp_settime(void *priv, struct timespec *ts)
+{
+ =A0 =A0 =A0 u64 ns;
+ =A0 =A0 =A0 unsigned long flags;
+ =A0 =A0 =A0 struct ixp46x_ts_regs *regs =3D priv;
+
+ =A0 =A0 =A0 ns =3D ts->tv_sec * 1000000000ULL;
+ =A0 =A0 =A0 ns +=3D ts->tv_nsec;
+
+ =A0 =A0 =A0 spin_lock_irqsave(&register_lock, flags);
+
+ =A0 =A0 =A0 sys_time_write(regs, ns);
+
+ =A0 =A0 =A0 spin_unlock_irqrestore(&register_lock, flags);
+
+ =A0 =A0 =A0 return 0;
+}
+
+static int ptp_ixp_gettimer(void *priv, int index, struct itimerspec *ts=

)

+{
+ =A0 =A0 =A0 /* We do not offer any ancillary features at all. */
+ =A0 =A0 =A0 return -EOPNOTSUPP;
+}
+
+static int ptp_ixp_settimer(void *p, int i, int abs, struct itimerspec *=

ts)

+{
+ =A0 =A0 =A0 /* We do not offer any ancillary features at all. */
+ =A0 =A0 =A0 return -EOPNOTSUPP;
+}
+
+static int ptp_ixp_enable(void *priv, struct ptp_clock_request *rq, int =

on)

+{
+ =A0 =A0 =A0 /* We do not offer any ancillary features at all. */
+ =A0 =A0 =A0 return -EOPNOTSUPP;
+}
+
+static struct ptp_clock_info ptp_ixp_caps =3D {
+ =A0 =A0 =A0 .owner =A0 =A0 =A0 =A0 =A0=3D THIS_MODULE,
+ =A0 =A0 =A0 .name =A0 =A0 =A0 =A0 =A0 =3D "IXP46X timer",
+ =A0 =A0 =A0 .max_adj =A0 =A0 =A0 =A0=3D 512000,
+ =A0 =A0 =A0 .n_alarm =A0 =A0 =A0 =A0=3D 0,
+ =A0 =A0 =A0 .n_ext_ts =A0 =A0 =A0 =3D 0,
+ =A0 =A0 =A0 .n_per_out =A0 =A0 =A0=3D 0,
+ =A0 =A0 =A0 .pps =A0 =A0 =A0 =A0 =A0 =A0=3D 0,
+ =A0 =A0 =A0 .priv =A0 =A0 =A0 =A0 =A0 =3D NULL,

If the value is '0' or NULL, just leave them out of the structure initializ=
er.

+ =A0 =A0 =A0 .adjfreq =A0 =A0 =A0 =A0=3D ptp_ixp_adjfreq,
+ =A0 =A0 =A0 .adjtime =A0 =A0 =A0 =A0=3D ptp_ixp_adjtime,
+ =A0 =A0 =A0 .gettime =A0 =A0 =A0 =A0=3D ptp_ixp_gettime,
+ =A0 =A0 =A0 .settime =A0 =A0 =A0 =A0=3D ptp_ixp_settime,
+ =A0 =A0 =A0 .gettimer =A0 =A0 =A0 =3D ptp_ixp_gettimer,
+ =A0 =A0 =A0 .settimer =A0 =A0 =A0 =3D ptp_ixp_settimer,
+ =A0 =A0 =A0 .enable =A0 =A0 =A0 =A0 =3D ptp_ixp_enable,
+};
+
+/* module operations */
+
+static struct {
+ =A0 =A0 =A0 struct ixp46x_ts_regs *regs;
+ =A0 =A0 =A0 struct ptp_clock *ptp_clock;
+} ixp_clock;
+
+static void __exit ptp_ixp_exit(void)
+{
+ =A0 =A0 =A0 ptp_clock_unregister(ixp_clock.ptp_clock);
+}
+
+static int __init ptp_ixp_init(void)
+{
+ =A0 =A0 =A0 ixp_clock.regs =3D
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 (struct ixp46x_ts_regs __iomem *)IXP4XX_TIM=

ESYNC_BASE_VIRT;

+
+ =A0 =A0 =A0 ptp_ixp_caps.priv =3D ixp_clock.regs;
+
+ =A0 =A0 =A0 ixp_clock.ptp_clock =3D ptp_clock_register(&ptp_ixp_caps);
+
+ =A0 =A0 =A0 if (IS_ERR(ixp_clock.ptp_clock))
+ =A0 =A0 =A0 =A0 =A0 =A0 =A0 return PTR_ERR(ixp_clock.ptp_clock);
+
+ =A0 =A0 =A0 ixp_write(&ixp_clock.regs->Addend, DEFAULT_ADDEND);
+
+ =A0 =A0 =A0 return 0;
+}
+
+module_init(ptp_ixp_init);
+module_exit(ptp_ixp_exit);

Keep module_init and module_exit with their respective function declaration=
s.

g.