// SPDX-License-Identifier: GPL-2.0+
/*
* TI Common Platform Time Sync
*
* Copyright (C) 2012 Richard Cochran <richardcochran@gmail.com>
*
*/
#include <linux/clk-provider.h>
#include <linux/err.h>
#include <linux/if.h>
#include <linux/hrtimer.h>
#include <linux/module.h>
#include <linux/net_tstamp.h>
#include <linux/ptp_classify.h>
#include <linux/time.h>
#include <linux/uaccess.h>
#include <linux/workqueue.h>
#include <linux/if_ether.h>
#include <linux/if_vlan.h>
#include "cpts.h"
#define CPTS_SKB_TX_WORK_TIMEOUT 1 /* jiffies */
#define CPTS_SKB_RX_TX_TMO 100 /*ms */
#define CPTS_EVENT_RX_TX_TIMEOUT (100) /* ms */
struct cpts_skb_cb_data {
u32 skb_mtype_seqid;
unsigned long tmo;
};
#define cpts_read32(c, r) readl_relaxed(&c->reg->r)
#define cpts_write32(c, v, r) writel_relaxed(v, &c->reg->r)
static int cpts_event_port(struct cpts_event *event)
{
return (event->high >> PORT_NUMBER_SHIFT) & PORT_NUMBER_MASK;
}
static int event_expired(struct cpts_event *event)
{
return time_after(jiffies, event->tmo);
}
static int event_type(struct cpts_event *event)
{
return (event->high >> EVENT_TYPE_SHIFT) & EVENT_TYPE_MASK;
}
static int cpts_fifo_pop(struct cpts *cpts, u32 *high, u32 *low)
{
u32 r = cpts_read32(cpts, intstat_raw);
if (r & TS_PEND_RAW) {
*high = cpts_read32(cpts, event_high);
*low = cpts_read32(cpts, event_low);
cpts_write32(cpts, EVENT_POP, event_pop);
return 0;
}
return -1;
}
static int cpts_purge_events(struct cpts *cpts)
{
struct list_head *this, *next;
struct cpts_event *event;
int removed = 0;
list_for_each_safe(this, next, &cpts->events) {
event = list_entry(this, struct cpts_event, list);
if (event_expired(event)) {
list_del_init(&event->list);
list_add(&event->list, &cpts->pool);
++removed;
}
}
if (removed)
dev_dbg(cpts->dev, "cpts: event pool cleaned up %d\n", removed);
return removed ? 0 : -1;
}
static void cpts_purge_txq(struct cpts *cpts)
{
struct cpts_skb_cb_data *skb_cb;
struct sk_buff *skb, *tmp;
int removed = 0;
skb_queue_walk_safe(&cpts->txq, skb, tmp) {
skb_cb = (struct cpts_skb_cb_data *)skb->cb;
if (time_after(jiffies, skb_cb->tmo)) {
__skb_unlink(skb, &cpts->txq);
dev_consume_skb_any(skb);
++removed;
}
}
if (removed)
dev_dbg(cpts->dev, "txq cleaned up %d\n", removed);
}
/*
* Returns zero if matching event type was found.
*/
static int cpts_fifo_read(struct cpts *cpts, int match)
{
struct ptp_clock_event pevent;
bool need_schedule = false;
struct cpts_event *event;
unsigned long flags;
int i, type = -1;
u32 hi, lo;
spin_lock_irqsave(&cpts->lock, flags);
for (i = 0; i < CPTS_FIFO_DEPTH; i++) {
if (cpts_fifo_pop(cpts, &hi, &lo))
break;
if (list_empty(&cpts->pool) && cpts_purge_events(cpts)) {
dev_warn(cpts->dev, "cpts: event pool empty\n");
break;
}
event = list_first_entry(&cpts->pool, struct cpts_event, list);
event->high = hi;
event->low = lo;
event->timestamp = timecounter_cyc2time(&cpts->tc, event->low);
type = event_type(event);
dev_dbg(cpts->dev, "CPTS_EV: %d high:%08X low:%08x\n",
type, event->high, event->low);
switch (type) {
case CPTS_EV_PUSH:
WRITE_ONCE(cpts->cur_timestamp, lo);
timecounter_read(&cpts->tc);
if (cpts->mult_new) {
cpts->cc.mult = cpts->mult_new;
cpts->mult_new = 0;
}
if (!cpts->irq_poll)
complete(&cpts->ts_push_complete);
break;
case CPTS_EV_TX:
case CPTS_EV_RX:
event->tmo = jiffies +
msecs_to_jiffies(CPTS_EVENT_RX_TX_TIMEOUT);
list_del_init(&event->list);
list_add_tail(&event->list, &cpts->events);
need_schedule = true;
break;
case CPTS_EV_ROLL:
case CPTS_EV_HALF:
break;
case CPTS_EV_HW:
pevent.timestamp = event->timestamp;
pevent.type = PTP_CLOCK_EXTTS;
pevent.index = cpts_event_port(event) - 1;
ptp_clock_event(cpts->clock, &pevent);
break;
default:
dev_err(cpts->dev, "cpts: unknown event type\n");
break;
}
if (type == match)
break;
}
spin_unlock_irqrestore(&cpts->lock, flags);
if (!cpts->irq_poll && need_schedule)
ptp_schedule_worker(cpts->clock, 0);
return type == match ? 0 : -1;
}
void cpts_misc_interrupt(struct cpts *cpts)
{
cpts_fifo_read(cpts, -1);
}
EXPORT_SYMBOL_GPL(cpts_misc_interrupt);
static u64 cpts_systim_read(const struct cyclecounter *cc)
{
struct cpts *cpts = container_of(cc, struct cpts, cc);
return READ_ONCE(cpts->cur_timestamp);
}
static void cpts_update_cur_time(struct cpts *cpts, int match,
struct ptp_system_timestamp *sts)
{
unsigned long flags;
reinit_completion(&cpts->ts_push_complete);
/* use spin_lock_irqsave() here as it has to run very fast */
spin_lock_irqsave(&cpts->lock, flags);
ptp_read_system_prets(sts);
cpts_write32(cpts, TS_PUSH, ts_push);
cpts_read32(cpts, ts_push);
ptp_read_system_postts(sts);
spin_unlock_irqrestore(&cpts->lock, flags);
if (cpts->irq_poll && cpts_fifo_read(cpts, match) && match != -1)
dev_err(cpts->dev, "cpts: unable to obtain a time stamp\n");
if (!cpts->irq_poll &&
!wait_for_completion_timeout(&cpts->ts_push_complete, HZ))
dev_err(cpts->dev, "cpts: obtain a time stamp timeout\n");
}
/* PTP clock operations */
static int cpts_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
{
struct cpts *cpts = container_of(ptp, struct cpts, info);
mutex_lock(&cpts->ptp_clk_mutex);
cpts->mult_new = adjust_by_scaled_ppm(cpts->cc_mult, scaled_ppm);
cpts_update_cur_time(cpts, CPTS_EV_PUSH, NULL);
mutex_unlock(&cpts->ptp_clk_mutex);
return 0;
}
static int cpts_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
{
struct cpts *cpts = container_of(ptp, struct cpts, info);
mutex_lock(&cpts->ptp_clk_mutex);
timecounter_adjtime(&cpts->tc, delta);
mutex_unlock(&cpts->ptp_clk_mutex);
return 0;
}
static int cpts_ptp_gettimeex(struct ptp_clock_info *ptp,
struct timespec64 *ts,
struct ptp_system_timestamp *sts)
{
struct cpts *cpts = container_of(ptp, struct cpts, info);
u64 ns;
mutex_lock(&cpts->ptp_clk_mutex);
cpts_update_cur_time(cpts, CPTS_EV_PUSH, sts);
ns = timecounter_read(&cpts->tc);
mutex_unlock(&cpts->ptp_clk_mutex);
*ts = ns_to_timespec64(ns);
return 0;
}
static int cpts_ptp_settime(struct ptp_clock_info *ptp,
const struct timespec64 *ts)
{
struct cpts *cpts = container_of(ptp, struct cpts, info);
u64 ns;
ns = timespec64_to_ns(ts);
mutex_lock(&cpts->ptp_clk_mutex);
timecounter_init(&cpts->tc, &cpts->cc, ns);
mutex_unlock(&cpts->ptp_clk_mutex);
return 0;
}
static int cpts_extts_enable(struct cpts *cpts, u32 index, int on)
{
u32 v;
if (((cpts->hw_ts_enable & BIT(index)) >> index) == on)
return 0;
mutex_lock(&cpts->ptp_clk_mutex);
v = cpts_read32(cpts, control);
if (on) {
v |= BIT(8 + index);
cpts->hw_ts_enable |= BIT(index);
} else {
v &= ~BIT(8 + index);
cpts->hw_ts_enable &= ~BIT(index);
}
cpts_write32(cpts, v, control);
mutex_unlock(&cpts->ptp_clk_mutex);
return 0;
}
static int cpts_ptp_enable(struct ptp_clock_info *ptp,
struct ptp_clock_request *rq, int on)
{
struct cpts *cpts = container_of(ptp, struct cpts, info);
switch (rq->type) {
case PTP_CLK_REQ_EXTTS:
return cpts_extts_enable(cpts, rq->extts.index, on);
default:
break;
}
return -EOPNOTSUPP;
}
static bool cpts_match_tx_ts(struct cpts *cpts, struct cpts_event *event)
{
struct sk_buff_head txq_list;
struct sk_buff *skb, *tmp;
unsigned long flags;
bool found = false;
u32 mtype_seqid;
mtype_seqid = event->high &
((MESSAGE_TYPE_MASK << MESSAGE_TYPE_SHIFT) |
(SEQUENCE_ID_MASK << SEQUENCE_ID_SHIFT) |
(EVENT_TYPE_MASK << EVENT_TYPE_SHIFT));
__skb_queue_head_init(&txq_list);
spin_lock_irqsave(&cpts->txq.lock, flags);
skb_queue_splice_init(&cpts->txq, &txq_list);
spin_unlock_irqrestore(&cpts->txq.lock, flags);
skb_queue_walk_safe(&txq_list, skb, tmp) {
struct skb_shared_hwtstamps ssh;
struct cpts_skb_cb_data *skb_cb =
(struct cpts_skb_cb_data *)skb->cb;
if (mtype_seqid == skb_cb->skb_mtype_seqid) {
memset(&ssh, 0, sizeof(ssh));
ssh.hwtstamp = ns_to_ktime(event->timestamp);
skb_tstamp_tx(skb, &ssh);
found = true;
__skb_unlink(skb, &txq_list);
dev_consume_skb_any(skb);
dev_dbg(cpts->dev, "match tx timestamp mtype_seqid %08x\n",
mtype_seqid);
break;
}
if (time_after(jiffies, skb_cb->tmo)) {
/* timeout any expired skbs over 1s */
dev_dbg(cpts->dev, "expiring tx timestamp from txq\n");
__skb_unlink(skb, &txq_list);
dev_consume_skb_any(skb);
}
}
spin_lock_irqsave(&cpts->txq.lock, flags);
skb_queue_splice(&txq_list, &cpts->txq);
spin_unlock_irqrestore(&cpts->txq.lock, flags);
return found;
}
static void cpts_process_events(struct cpts *cpts)
{
struct list_head *this, *next;
struct cpts_event *event;
LIST_HEAD(events_free);
unsigned long flags;
LIST_HEAD(events);
spin_lock_irqsave(&cpts->lock, flags);
list_splice_init(&cpts->events, &events);
spin_unlock_irqrestore(&cpts->lock, flags);
list_for_each_safe(this, next, &events) {
event = list_entry(this, struct cpts_event, list);
if (cpts_match_tx_ts(cpts, event) ||
time_after(jiffies, event->tmo)) {
list_del_init(&event->list);
list_add(&event->list, &events_free);
}
}
spin_lock_irqsave(&cpts->lock, flags);
list_splice_tail(&events, &cpts->events);
list_splice_tail(&events_free, &cpts->pool);
spin_unlock_irqrestore(&cpts->lock, flags);
}
static long cpts_overflow_check(struct ptp_clock_info *ptp)
{
struct cpts *cpts = container_of(ptp, struct cpts, info);
unsigned long delay = cpts->ov_check_period;
unsigned long flags;
u64 ns;
mutex_lock(&cpts->ptp_clk_mutex);
cpts_update_cur_time(cpts, -1, NULL);
ns = timecounter_read(&cpts->tc);
cpts_process_events(cpts);
spin_lock_irqsave(&cpts->txq.lock, flags);
if (!skb_queue_empty(&cpts->txq)) {
cpts_purge_txq(cpts);
if (!skb_queue_empty(&cpts->txq))
delay = CPTS_SKB_TX_WORK_TIMEOUT;
}
spin_unlock_irqrestore(&cpts->txq.lock, flags);
dev_dbg(cpts->dev, "cpts overflow check at %lld\n", ns);
mutex_unlock(&cpts->ptp_clk_mutex);
return (long)delay;
}
static const struct ptp_clock_info cpts_info = {
.owner = THIS_MODULE,
.name = "CTPS timer",
.max_adj = 1000000,
.n_ext_ts = 0,
.n_pins = 0,
.pps = 0,
.adjfine = cpts_ptp_adjfine,
.adjtime = cpts_ptp_adjtime,
.gettimex64 = cpts_ptp_gettimeex,
.settime64 = cpts_ptp_settime,
.enable = cpts_ptp_enable,
.do_aux_work = cpts_overflow_check,
};
static int cpts_skb_get_mtype_seqid(struct sk_buff *skb, u32 *mtype_seqid)
{
unsigned int ptp_class = ptp_classify_raw(skb);
struct ptp_header *hdr;
u8 msgtype;
u16 seqid;
if (ptp_class == PTP_CLASS_NONE)
return 0;
hdr = ptp_parse_header(skb, ptp_class);
if (!hdr)
return 0;
msgtype = ptp_get_msgtype(hdr, ptp_class);
seqid = ntohs(hdr->sequence_id);
*mtype_seqid = (msgtype & MESSAGE_TYPE_MASK) << MESSAGE_TYPE_SHIFT;
*mtype_seqid |= (seqid & SEQUENCE_ID_MASK) << SEQUENCE_ID_SHIFT;
return 1;
}
static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb,
int ev_type, u32 skb_mtype_seqid)
{
struct list_head *this, *next;
struct cpts_event *event;
unsigned long flags;
u32 mtype_seqid;
u64 ns = 0;
cpts_fifo_read(cpts, -1);
spin_lock_irqsave(&cpts->lock, flags);
list_for_each_safe(this, next, &cpts->events) {
event = list_entry(this, struct cpts_event, list);
if (event_expired(event)) {
list_del_init(&event->list);
list_add(&event->list, &cpts->pool);
continue;
}
mtype_seqid = event->high &
((MESSAGE_TYPE_MASK << MESSAGE_TYPE_SHIFT) |
(SEQUENCE_ID_MASK << SEQUENCE_ID_SHIFT) |
(EVENT_TYPE_MASK << EVENT_TYPE_SHIFT));
if (mtype_seqid == skb_mtype_seqid) {
ns = event->timestamp;
list_del_init(&event->list);
list_add(&event->list, &cpts->pool);
break;
}
}
spin_unlock_irqrestore(&cpts->lock, flags);
return ns;
}
void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
{
struct cpts_skb_cb_data *skb_cb = (struct cpts_skb_cb_data *)skb->cb;
struct skb_shared_hwtstamps *ssh;
int ret;
u64 ns;
/* cpts_rx_timestamp() is called before eth_type_trans(), so
* skb MAC Hdr properties are not configured yet. Hence need to
* reset skb MAC header here
*/
skb_reset_mac_header(skb);
ret = cpts_skb_get_mtype_seqid(skb, &skb_cb->skb_mtype_seqid);
if (!ret)
return;
skb_cb->skb_mtype_seqid |= (CPTS_EV_RX << EVENT_TYPE_SHIFT);
dev_dbg(cpts->dev, "%s mtype seqid %08x\n",
__func__, skb_cb->skb_mtype_seqid);
ns = cpts_find_ts(cpts, skb, CPTS_EV_RX, skb_cb->skb_mtype_seqid);
if (!ns)
return;
ssh = skb_hwtstamps(skb);
memset(ssh, 0, sizeof(*ssh));
ssh->hwtstamp = ns_to_ktime(ns);
}
EXPORT_SYMBOL_GPL(cpts_rx_timestamp);
void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
{
struct cpts_skb_cb_data *skb_cb = (struct cpts_skb_cb_data *)skb->cb;
int ret;
if (!(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS))
return;
ret = cpts_skb_get_mtype_seqid(skb, &skb_cb->skb_mtype_seqid);
if (!ret)
return;
skb_cb->skb_mtype_seqid |= (CPTS_EV_TX << EVENT_TYPE_SHIFT);
dev_dbg(cpts->dev, "%s mtype seqid %08x\n",
__func__, skb_cb->skb_mtype_seqid);
/* Always defer TX TS processing to PTP worker */
skb_get(skb);
/* get the timestamp for timeouts */
skb_cb->tmo = jiffies + msecs_to_jiffies(CPTS_SKB_RX_TX_TMO);
skb_queue_tail(&cpts->txq, skb);
ptp_schedule_worker(cpts->clock, 0);
}
EXPORT_SYMBOL_GPL(cpts_tx_timestamp);
int cpts_register(struct cpts *cpts)
{
int err, i;
skb_queue_head_init(&cpts->txq);
INIT_LIST_HEAD(&cpts->events);
INIT_LIST_HEAD(&cpts->pool);
for (i = 0; i < CPTS_MAX_EVENTS; i++)
list_add(&cpts->pool_data[i].list, &cpts->pool);
err = clk_enable(cpts->refclk);
if (err)
return err;
cpts_write32(cpts, CPTS_EN, control);
cpts_write32(cpts, TS_PEND_EN, int_enable);
timecounter_init(&cpts->tc, &cpts->cc, ktime_get_real_ns());
cpts->clock = ptp_clock_register(&cpts->info, cpts->dev);
if (IS_ERR(cpts->clock)) {
err = PTR_ERR(cpts->clock);
cpts->clock = NULL;
goto err_ptp;
}
cpts->phc_index = ptp_clock_index(cpts->clock);
ptp_schedule_worker(cpts->clock, cpts->ov_check_period);
return 0;
err_ptp:
clk_disable(cpts->refclk);
return err;
}
EXPORT_SYMBOL_GPL(cpts_register);
void cpts_unregister(struct cpts *cpts)
{
if (WARN_ON(!cpts->clock))
return;
ptp_clock_unregister(cpts->clock);
cpts->clock = NULL;
cpts->phc_index = -1;
cpts_write32(cpts, 0, int_enable);
cpts_write32(cpts, 0, control);
/* Drop all packet */
skb_queue_purge(&cpts->txq);
clk_disable(cpts->refclk);
}
EXPORT_SYMBOL_GPL(cpts_unregister);
static void cpts_calc_mult_shift(struct cpts *cpts)
{
u64 frac, maxsec, ns;
u32 freq;
freq = clk_get_rate(cpts->refclk);
/* Calc the maximum number of seconds which we can run before
* wrapping around.
*/
maxsec = cpts->cc.mask;
do_div(maxsec, freq);
/* limit conversation rate to 10 sec as higher values will produce
* too small mult factors and so reduce the conversion accuracy
*/
if (maxsec > 10)
maxsec = 10;
/* Calc overflow check period (maxsec / 2) */
cpts->ov_check_period = (HZ * maxsec) / 2;
dev_info(cpts->dev, "cpts: overflow check period %lu (jiffies)\n",
cpts->ov_check_period);
if (cpts->cc.mult || cpts->cc.shift)
return;
clocks_calc_mult_shift(&cpts->cc.mult, &cpts->cc.shift,
freq, NSEC_PER_SEC, maxsec);
frac = 0;
ns = cyclecounter_cyc2ns(&cpts->cc, freq, cpts->cc.mask, &frac);
dev_info(cpts->dev,
"CPTS: ref_clk_freq:%u calc_mult:%u calc_shift:%u error:%lld nsec/sec\n",
freq, cpts->cc.mult, cpts->cc.shift, (ns - NSEC_PER_SEC));
}
static int cpts_of_mux_clk_setup(struct cpts *cpts, struct device_node *node)
{
struct device_node *refclk_np;
const char **parent_names;
unsigned int num_parents;
struct clk_hw *clk_hw;
int ret = -EINVAL;
u32 *mux_table;
refclk_np = of_get_child_by_name(node, "cpts-refclk-mux");
if (!refclk_np)
/* refclk selection supported not for all SoCs */
return 0;
num_parents = of_clk_get_parent_count(refclk_np);
if (num_parents < 1) {
dev_err(cpts->dev, "mux-clock %s must have parents\n",
refclk_np->name);
goto mux_fail;
}
parent_names = devm_kcalloc(cpts->dev, num_parents,
sizeof(*parent_names), GFP_KERNEL);
mux_table = devm_kcalloc(cpts->dev, num_parents, sizeof(*mux_table),
GFP_KERNEL);
if (!mux_table || !parent_names) {
ret = -ENOMEM;
goto mux_fail;
}
of_clk_parent_fill(refclk_np, parent_names, num_parents);
ret = of_property_read_variable_u32_array(refclk_np, "ti,mux-tbl",
mux_table,
num_parents, num_parents);
if (ret < 0)
goto mux_fail;
clk_hw = clk_hw_register_mux_table(cpts->dev, refclk_np->name,
parent_names, num_parents,
0,
&cpts->reg->rftclk_sel, 0, 0x1F,
0, mux_table, NULL);
if (IS_ERR(clk_hw)) {
ret = PTR_ERR(clk_hw);
goto mux_fail;
}
ret = devm_add_action_or_reset(cpts->dev,
(void(*)(void *))clk_hw_unregister_mux,
clk_hw);
if (ret) {
dev_err(cpts->dev, "add clkmux unreg action %d", ret);
goto mux_fail;
}
ret = of_clk_add_hw_provider(refclk_np, of_clk_hw_simple_get, clk_hw);
if (ret)
goto mux_fail;
ret = devm_add_action_or_reset(cpts->dev,
(void(*)(void *))of_clk_del_provider,
refclk_np);
if (ret) {
dev_err(cpts->dev, "add clkmux provider unreg action %d", ret);
goto mux_fail;
}
return ret;
mux_fail:
of_node_put(refclk_np);
return ret;
}
static int cpts_of_parse(struct cpts *cpts, struct device_node *node)
{
int ret = -EINVAL;
u32 prop;
if (!of_property_read_u32(node, "cpts_clock_mult", &prop))
cpts->cc.mult = prop;
if (!of_property_read_u32(node, "cpts_clock_shift", &prop))
cpts->cc.shift = prop;
if ((cpts->cc.mult && !cpts->cc.shift) ||
(!cpts->cc.mult && cpts->cc.shift))
goto of_error;
return cpts_of_mux_clk_setup(cpts, node);
of_error:
dev_err(cpts->dev, "CPTS: Missing property in the DT.\n");
return ret;
}
struct cpts *cpts_create(struct device *dev, void __iomem *regs,
struct device_node *node, u32 n_ext_ts)
{
struct cpts *cpts;
int ret;
cpts = devm_kzalloc(dev, sizeof(*cpts), GFP_KERNEL);
if (!cpts)
return ERR_PTR(-ENOMEM);
cpts->dev = dev;
cpts->reg = (struct cpsw_cpts __iomem *)regs;
cpts->irq_poll = true;
spin_lock_init(&cpts->lock);
mutex_init(&cpts->ptp_clk_mutex);
init_completion(&cpts->ts_push_complete);
ret = cpts_of_parse(cpts, node);
if (ret)
return ERR_PTR(ret);
cpts->refclk = devm_get_clk_from_child(dev, node, "cpts");
if (IS_ERR(cpts->refclk))
/* try get clk from dev node for compatibility */
cpts->refclk = devm_clk_get(dev, "cpts");
if (IS_ERR(cpts->refclk)) {
dev_err(dev, "Failed to get cpts refclk %ld\n",
PTR_ERR(cpts->refclk));
return ERR_CAST(cpts->refclk);
}
ret = clk_prepare(cpts->refclk);
if (ret)
return ERR_PTR(ret);
cpts->cc.read = cpts_systim_read;
cpts->cc.mask = CLOCKSOURCE_MASK(32);
cpts->info = cpts_info;
cpts->phc_index = -1;
if (n_ext_ts)
cpts->info.n_ext_ts = n_ext_ts;
cpts_calc_mult_shift(cpts);
/* save cc.mult original value as it can be modified
* by cpts_ptp_adjfine().
*/
cpts->cc_mult = cpts->cc.mult;
return cpts;
}
EXPORT_SYMBOL_GPL(cpts_create);
void cpts_release(struct cpts *cpts)
{
if (!cpts)
return;
if (WARN_ON(!cpts->refclk))
return;
clk_unprepare(cpts->refclk);
}
EXPORT_SYMBOL_GPL(cpts_release);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("TI CPTS driver");
MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");