root/drivers/ptp/ptp_clockmatrix.c
// SPDX-License-Identifier: GPL-2.0+
/*
 * PTP hardware clock driver for the IDT ClockMatrix(TM) family of timing and
 * synchronization devices.
 *
 * Copyright (C) 2019 Integrated Device Technology, Inc., a Renesas Company.
 */
#include <linux/firmware.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/ptp_clock_kernel.h>
#include <linux/delay.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/timekeeping.h>
#include <linux/string.h>
#include <linux/of.h>
#include <linux/mfd/rsmu.h>
#include <linux/mfd/idt8a340_reg.h>
#include <linux/unaligned.h>

#include "ptp_private.h"
#include "ptp_clockmatrix.h"

MODULE_DESCRIPTION("Driver for IDT ClockMatrix(TM) family");
MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");
MODULE_AUTHOR("IDT support-1588 <IDT-support-1588@lm.renesas.com>");
MODULE_VERSION("1.0");
MODULE_LICENSE("GPL");

/*
 * The name of the firmware file to be loaded
 * over-rides any automatic selection
 */
static char *firmware;
module_param(firmware, charp, 0);

#define SETTIME_CORRECTION (0)
#define EXTTS_PERIOD_MS (95)

static int _idtcm_adjfine(struct idtcm_channel *channel, long scaled_ppm);

static inline int idtcm_read(struct idtcm *idtcm,
                             u16 module,
                             u16 regaddr,
                             u8 *buf,
                             u16 count)
{
        return regmap_bulk_read(idtcm->regmap, module + regaddr, buf, count);
}

static inline int idtcm_write(struct idtcm *idtcm,
                              u16 module,
                              u16 regaddr,
                              u8 *buf,
                              u16 count)
{
        return regmap_bulk_write(idtcm->regmap, module + regaddr, buf, count);
}

static int contains_full_configuration(struct idtcm *idtcm,
                                       const struct firmware *fw)
{
        struct idtcm_fwrc *rec = (struct idtcm_fwrc *)fw->data;
        u16 scratch = IDTCM_FW_REG(idtcm->fw_ver, V520, SCRATCH);
        s32 full_count;
        s32 count = 0;
        u16 regaddr;
        u8 loaddr;
        s32 len;

        /* 4 bytes skipped every 0x80 */
        full_count = (scratch - GPIO_USER_CONTROL) -
                     ((scratch >> 7) - (GPIO_USER_CONTROL >> 7)) * 4;

        /* If the firmware contains 'full configuration' SM_RESET can be used
         * to ensure proper configuration.
         *
         * Full configuration is defined as the number of programmable
         * bytes within the configuration range minus page offset addr range.
         */
        for (len = fw->size; len > 0; len -= sizeof(*rec)) {
                regaddr = rec->hiaddr << 8;
                regaddr |= rec->loaddr;

                loaddr = rec->loaddr;

                rec++;

                /* Top (status registers) and bottom are read-only */
                if (regaddr < GPIO_USER_CONTROL || regaddr >= scratch)
                        continue;

                /* Page size 128, last 4 bytes of page skipped */
                if ((loaddr > 0x7b && loaddr <= 0x7f) || loaddr > 0xfb)
                        continue;

                count++;
        }

        return (count >= full_count);
}

static int char_array_to_timespec(u8 *buf,
                                  u8 count,
                                  struct timespec64 *ts)
{
        u8 i;
        u64 nsec;
        time64_t sec;

        if (count < TOD_BYTE_COUNT)
                return 1;

        /* Sub-nanoseconds are in buf[0]. */
        nsec = buf[4];
        for (i = 0; i < 3; i++) {
                nsec <<= 8;
                nsec |= buf[3 - i];
        }

        sec = buf[10];
        for (i = 0; i < 5; i++) {
                sec <<= 8;
                sec |= buf[9 - i];
        }

        ts->tv_sec = sec;
        ts->tv_nsec = nsec;

        return 0;
}

static int timespec_to_char_array(struct timespec64 const *ts,
                                  u8 *buf,
                                  u8 count)
{
        u8 i;
        s32 nsec;
        time64_t sec;

        if (count < TOD_BYTE_COUNT)
                return 1;

        nsec = ts->tv_nsec;
        sec = ts->tv_sec;

        /* Sub-nanoseconds are in buf[0]. */
        buf[0] = 0;
        for (i = 1; i < 5; i++) {
                buf[i] = nsec & 0xff;
                nsec >>= 8;
        }

        for (i = 5; i < TOD_BYTE_COUNT; i++) {

                buf[i] = sec & 0xff;
                sec >>= 8;
        }

        return 0;
}

static int idtcm_strverscmp(const char *version1, const char *version2)
{
        u8 ver1[3], ver2[3];
        int i;

        if (sscanf(version1, "%hhu.%hhu.%hhu",
                   &ver1[0], &ver1[1], &ver1[2]) != 3)
                return -1;
        if (sscanf(version2, "%hhu.%hhu.%hhu",
                   &ver2[0], &ver2[1], &ver2[2]) != 3)
                return -1;

        for (i = 0; i < 3; i++) {
                if (ver1[i] > ver2[i])
                        return 1;
                if (ver1[i] < ver2[i])
                        return -1;
        }

        return 0;
}

static enum fw_version idtcm_fw_version(const char *version)
{
        enum fw_version ver = V_DEFAULT;

        if (idtcm_strverscmp(version, "4.8.7") >= 0)
                ver = V487;

        if (idtcm_strverscmp(version, "5.2.0") >= 0)
                ver = V520;

        return ver;
}

static int clear_boot_status(struct idtcm *idtcm)
{
        u8 buf[4] = {0};

        return idtcm_write(idtcm, GENERAL_STATUS, BOOT_STATUS, buf, sizeof(buf));
}

static int read_boot_status(struct idtcm *idtcm, u32 *status)
{
        int err;
        u8 buf[4] = {0};

        err = idtcm_read(idtcm, GENERAL_STATUS, BOOT_STATUS, buf, sizeof(buf));

        *status = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];

        return err;
}

static int wait_for_boot_status_ready(struct idtcm *idtcm)
{
        u32 status = 0;
        u8 i = 30;      /* 30 * 100ms = 3s */
        int err;

        do {
                err = read_boot_status(idtcm, &status);
                if (err)
                        return err;

                if (status == 0xA0)
                        return 0;

                msleep(100);
                i--;

        } while (i);

        dev_warn(idtcm->dev, "%s timed out", __func__);

        return -EBUSY;
}

static int arm_tod_read_trig_sel_refclk(struct idtcm_channel *channel, u8 ref)
{
        struct idtcm *idtcm = channel->idtcm;
        u16 tod_read_cmd = IDTCM_FW_REG(idtcm->fw_ver, V520, TOD_READ_SECONDARY_CMD);
        u8 val = 0;
        int err;

        val &= ~(WR_REF_INDEX_MASK << WR_REF_INDEX_SHIFT);
        val |= (ref << WR_REF_INDEX_SHIFT);

        err = idtcm_write(idtcm, channel->tod_read_secondary,
                          TOD_READ_SECONDARY_SEL_CFG_0, &val, sizeof(val));
        if (err)
                return err;

        val = 0 | (SCSR_TOD_READ_TRIG_SEL_REFCLK << TOD_READ_TRIGGER_SHIFT);

        err = idtcm_write(idtcm, channel->tod_read_secondary, tod_read_cmd,
                          &val, sizeof(val));
        if (err)
                dev_err(idtcm->dev, "%s: err = %d", __func__, err);

        return err;
}

static bool is_single_shot(u8 mask)
{
        /* Treat single bit ToD masks as continuous trigger */
        return !(mask <= 8 && is_power_of_2(mask));
}

static int idtcm_extts_enable(struct idtcm_channel *channel,
                              struct ptp_clock_request *rq, int on)
{
        u8 index = rq->extts.index;
        struct idtcm *idtcm;
        u8 mask = 1 << index;
        int err = 0;
        u8 old_mask;
        int ref;

        idtcm = channel->idtcm;
        old_mask = idtcm->extts_mask;

        if (index >= MAX_TOD)
                return -EINVAL;

        if (on) {
                /* Support triggering more than one TOD_0/1/2/3 by same pin */
                /* Use the pin configured for the channel */
                ref = ptp_find_pin(channel->ptp_clock, PTP_PF_EXTTS, channel->tod);

                if (ref < 0) {
                        dev_err(idtcm->dev, "%s: No valid pin found for TOD%d!\n",
                                __func__, channel->tod);
                        return -EBUSY;
                }

                err = arm_tod_read_trig_sel_refclk(&idtcm->channel[index], ref);

                if (err == 0) {
                        idtcm->extts_mask |= mask;
                        idtcm->event_channel[index] = channel;
                        idtcm->channel[index].refn = ref;
                        idtcm->extts_single_shot = is_single_shot(idtcm->extts_mask);

                        if (old_mask)
                                return 0;

                        schedule_delayed_work(&idtcm->extts_work,
                                              msecs_to_jiffies(EXTTS_PERIOD_MS));
                }
        } else {
                idtcm->extts_mask &= ~mask;
                idtcm->extts_single_shot = is_single_shot(idtcm->extts_mask);

                if (idtcm->extts_mask == 0)
                        cancel_delayed_work(&idtcm->extts_work);
        }

        return err;
}

static int read_sys_apll_status(struct idtcm *idtcm, u8 *status)
{
        return idtcm_read(idtcm, STATUS, DPLL_SYS_APLL_STATUS, status,
                          sizeof(u8));
}

static int read_sys_dpll_status(struct idtcm *idtcm, u8 *status)
{
        return idtcm_read(idtcm, STATUS, DPLL_SYS_STATUS, status, sizeof(u8));
}

static int wait_for_sys_apll_dpll_lock(struct idtcm *idtcm)
{
        unsigned long timeout = jiffies + msecs_to_jiffies(LOCK_TIMEOUT_MS);
        u8 apll = 0;
        u8 dpll = 0;
        int err;

        do {
                err = read_sys_apll_status(idtcm, &apll);
                if (err)
                        return err;

                err = read_sys_dpll_status(idtcm, &dpll);
                if (err)
                        return err;

                apll &= SYS_APLL_LOSS_LOCK_LIVE_MASK;
                dpll &= DPLL_SYS_STATE_MASK;

                if (apll == SYS_APLL_LOSS_LOCK_LIVE_LOCKED &&
                    dpll == DPLL_STATE_LOCKED) {
                        return 0;
                } else if (dpll == DPLL_STATE_FREERUN ||
                           dpll == DPLL_STATE_HOLDOVER ||
                           dpll == DPLL_STATE_OPEN_LOOP) {
                        dev_warn(idtcm->dev,
                                "No wait state: DPLL_SYS_STATE %d", dpll);
                        return -EPERM;
                }

                msleep(LOCK_POLL_INTERVAL_MS);
        } while (time_is_after_jiffies(timeout));

        dev_warn(idtcm->dev,
                 "%d ms lock timeout: SYS APLL Loss Lock %d  SYS DPLL state %d",
                 LOCK_TIMEOUT_MS, apll, dpll);

        return -ETIME;
}

static void wait_for_chip_ready(struct idtcm *idtcm)
{
        if (wait_for_boot_status_ready(idtcm))
                dev_warn(idtcm->dev, "BOOT_STATUS != 0xA0");

        if (wait_for_sys_apll_dpll_lock(idtcm))
                dev_warn(idtcm->dev,
                         "Continuing while SYS APLL/DPLL is not locked");
}

static int _idtcm_gettime_triggered(struct idtcm_channel *channel,
                                    struct timespec64 *ts)
{
        struct idtcm *idtcm = channel->idtcm;
        u16 tod_read_cmd = IDTCM_FW_REG(idtcm->fw_ver, V520, TOD_READ_SECONDARY_CMD);
        u8 buf[TOD_BYTE_COUNT];
        u8 trigger;
        int err;

        err = idtcm_read(idtcm, channel->tod_read_secondary,
                         tod_read_cmd, &trigger, sizeof(trigger));
        if (err)
                return err;

        if (trigger & TOD_READ_TRIGGER_MASK)
                return -EBUSY;

        err = idtcm_read(idtcm, channel->tod_read_secondary,
                         TOD_READ_SECONDARY_BASE, buf, sizeof(buf));
        if (err)
                return err;

        return char_array_to_timespec(buf, sizeof(buf), ts);
}

static int _idtcm_gettime(struct idtcm_channel *channel,
                          struct timespec64 *ts, u8 timeout)
{
        struct idtcm *idtcm = channel->idtcm;
        u16 tod_read_cmd = IDTCM_FW_REG(idtcm->fw_ver, V520, TOD_READ_PRIMARY_CMD);
        u8 buf[TOD_BYTE_COUNT];
        u8 trigger;
        int err;

        /* wait trigger to be 0 */
        do {
                if (timeout-- == 0)
                        return -EIO;

                if (idtcm->calculate_overhead_flag)
                        idtcm->start_time = ktime_get_raw();

                err = idtcm_read(idtcm, channel->tod_read_primary,
                                 tod_read_cmd, &trigger,
                                 sizeof(trigger));
                if (err)
                        return err;
        } while (trigger & TOD_READ_TRIGGER_MASK);

        err = idtcm_read(idtcm, channel->tod_read_primary,
                         TOD_READ_PRIMARY_BASE, buf, sizeof(buf));
        if (err)
                return err;

        err = char_array_to_timespec(buf, sizeof(buf), ts);

        return err;
}

static int idtcm_extts_check_channel(struct idtcm *idtcm, u8 todn)
{
        struct idtcm_channel *ptp_channel, *extts_channel;
        struct ptp_clock_event event;
        struct timespec64 ts;
        u32 dco_delay = 0;
        int err;

        extts_channel = &idtcm->channel[todn];
        ptp_channel = idtcm->event_channel[todn];

        if (extts_channel == ptp_channel)
                dco_delay = ptp_channel->dco_delay;

        err = _idtcm_gettime_triggered(extts_channel, &ts);
        if (err)
                return err;

        /* Triggered - save timestamp */
        event.type = PTP_CLOCK_EXTTS;
        event.index = todn;
        event.timestamp = timespec64_to_ns(&ts) - dco_delay;
        ptp_clock_event(ptp_channel->ptp_clock, &event);

        return err;
}

static int _idtcm_gettime_immediate(struct idtcm_channel *channel,
                                    struct timespec64 *ts)
{
        struct idtcm *idtcm = channel->idtcm;

        u16 tod_read_cmd = IDTCM_FW_REG(idtcm->fw_ver, V520, TOD_READ_PRIMARY_CMD);
        u8 val = (SCSR_TOD_READ_TRIG_SEL_IMMEDIATE << TOD_READ_TRIGGER_SHIFT);
        int err;

        err = idtcm_write(idtcm, channel->tod_read_primary,
                          tod_read_cmd, &val, sizeof(val));
        if (err)
                return err;

        return _idtcm_gettime(channel, ts, 10);
}

static int _sync_pll_output(struct idtcm *idtcm,
                            u8 pll,
                            u8 sync_src,
                            u8 qn,
                            u8 qn_plus_1)
{
        int err;
        u8 val;
        u16 sync_ctrl0;
        u16 sync_ctrl1;
        u8 temp;

        if (qn == 0 && qn_plus_1 == 0)
                return 0;

        switch (pll) {
        case 0:
                sync_ctrl0 = HW_Q0_Q1_CH_SYNC_CTRL_0;
                sync_ctrl1 = HW_Q0_Q1_CH_SYNC_CTRL_1;
                break;
        case 1:
                sync_ctrl0 = HW_Q2_Q3_CH_SYNC_CTRL_0;
                sync_ctrl1 = HW_Q2_Q3_CH_SYNC_CTRL_1;
                break;
        case 2:
                sync_ctrl0 = HW_Q4_Q5_CH_SYNC_CTRL_0;
                sync_ctrl1 = HW_Q4_Q5_CH_SYNC_CTRL_1;
                break;
        case 3:
                sync_ctrl0 = HW_Q6_Q7_CH_SYNC_CTRL_0;
                sync_ctrl1 = HW_Q6_Q7_CH_SYNC_CTRL_1;
                break;
        case 4:
                sync_ctrl0 = HW_Q8_CH_SYNC_CTRL_0;
                sync_ctrl1 = HW_Q8_CH_SYNC_CTRL_1;
                break;
        case 5:
                sync_ctrl0 = HW_Q9_CH_SYNC_CTRL_0;
                sync_ctrl1 = HW_Q9_CH_SYNC_CTRL_1;
                break;
        case 6:
                sync_ctrl0 = HW_Q10_CH_SYNC_CTRL_0;
                sync_ctrl1 = HW_Q10_CH_SYNC_CTRL_1;
                break;
        case 7:
                sync_ctrl0 = HW_Q11_CH_SYNC_CTRL_0;
                sync_ctrl1 = HW_Q11_CH_SYNC_CTRL_1;
                break;
        default:
                return -EINVAL;
        }

        val = SYNCTRL1_MASTER_SYNC_RST;

        /* Place master sync in reset */
        err = idtcm_write(idtcm, 0, sync_ctrl1, &val, sizeof(val));
        if (err)
                return err;

        err = idtcm_write(idtcm, 0, sync_ctrl0, &sync_src, sizeof(sync_src));
        if (err)
                return err;

        /* Set sync trigger mask */
        val |= SYNCTRL1_FBDIV_FRAME_SYNC_TRIG | SYNCTRL1_FBDIV_SYNC_TRIG;

        if (qn)
                val |= SYNCTRL1_Q0_DIV_SYNC_TRIG;

        if (qn_plus_1)
                val |= SYNCTRL1_Q1_DIV_SYNC_TRIG;

        err = idtcm_write(idtcm, 0, sync_ctrl1, &val, sizeof(val));
        if (err)
                return err;

        /* PLL5 can have OUT8 as second additional output. */
        if (pll == 5 && qn_plus_1 != 0) {
                err = idtcm_read(idtcm, 0, HW_Q8_CTRL_SPARE,
                                 &temp, sizeof(temp));
                if (err)
                        return err;

                temp &= ~(Q9_TO_Q8_SYNC_TRIG);

                err = idtcm_write(idtcm, 0, HW_Q8_CTRL_SPARE,
                                  &temp, sizeof(temp));
                if (err)
                        return err;

                temp |= Q9_TO_Q8_SYNC_TRIG;

                err = idtcm_write(idtcm, 0, HW_Q8_CTRL_SPARE,
                                  &temp, sizeof(temp));
                if (err)
                        return err;
        }

        /* PLL6 can have OUT11 as second additional output. */
        if (pll == 6 && qn_plus_1 != 0) {
                err = idtcm_read(idtcm, 0, HW_Q11_CTRL_SPARE,
                                 &temp, sizeof(temp));
                if (err)
                        return err;

                temp &= ~(Q10_TO_Q11_SYNC_TRIG);

                err = idtcm_write(idtcm, 0, HW_Q11_CTRL_SPARE,
                                  &temp, sizeof(temp));
                if (err)
                        return err;

                temp |= Q10_TO_Q11_SYNC_TRIG;

                err = idtcm_write(idtcm, 0, HW_Q11_CTRL_SPARE,
                                  &temp, sizeof(temp));
                if (err)
                        return err;
        }

        /* Place master sync out of reset */
        val &= ~(SYNCTRL1_MASTER_SYNC_RST);
        err = idtcm_write(idtcm, 0, sync_ctrl1, &val, sizeof(val));

        return err;
}

static int idtcm_sync_pps_output(struct idtcm_channel *channel)
{
        struct idtcm *idtcm = channel->idtcm;
        u8 pll;
        u8 qn;
        u8 qn_plus_1;
        int err = 0;
        u8 out8_mux = 0;
        u8 out11_mux = 0;
        u8 temp;
        u16 output_mask = channel->output_mask;

        err = idtcm_read(idtcm, 0, HW_Q8_CTRL_SPARE,
                         &temp, sizeof(temp));
        if (err)
                return err;

        if ((temp & Q9_TO_Q8_FANOUT_AND_CLOCK_SYNC_ENABLE_MASK) ==
            Q9_TO_Q8_FANOUT_AND_CLOCK_SYNC_ENABLE_MASK)
                out8_mux = 1;

        err = idtcm_read(idtcm, 0, HW_Q11_CTRL_SPARE,
                         &temp, sizeof(temp));
        if (err)
                return err;

        if ((temp & Q10_TO_Q11_FANOUT_AND_CLOCK_SYNC_ENABLE_MASK) ==
            Q10_TO_Q11_FANOUT_AND_CLOCK_SYNC_ENABLE_MASK)
                out11_mux = 1;

        for (pll = 0; pll < 8; pll++) {
                qn = 0;
                qn_plus_1 = 0;

                if (pll < 4) {
                        /* First 4 pll has 2 outputs */
                        qn = output_mask & 0x1;
                        output_mask = output_mask >> 1;
                        qn_plus_1 = output_mask & 0x1;
                        output_mask = output_mask >> 1;
                } else if (pll == 4) {
                        if (out8_mux == 0) {
                                qn = output_mask & 0x1;
                                output_mask = output_mask >> 1;
                        }
                } else if (pll == 5) {
                        if (out8_mux) {
                                qn_plus_1 = output_mask & 0x1;
                                output_mask = output_mask >> 1;
                        }
                        qn = output_mask & 0x1;
                        output_mask = output_mask >> 1;
                } else if (pll == 6) {
                        qn = output_mask & 0x1;
                        output_mask = output_mask >> 1;
                        if (out11_mux) {
                                qn_plus_1 = output_mask & 0x1;
                                output_mask = output_mask >> 1;
                        }
                } else if (pll == 7) {
                        if (out11_mux == 0) {
                                qn = output_mask & 0x1;
                                output_mask = output_mask >> 1;
                        }
                }

                if (qn != 0 || qn_plus_1 != 0)
                        err = _sync_pll_output(idtcm, pll, channel->sync_src,
                                               qn, qn_plus_1);

                if (err)
                        return err;
        }

        return err;
}

static int _idtcm_set_dpll_hw_tod(struct idtcm_channel *channel,
                                  struct timespec64 const *ts,
                                  enum hw_tod_write_trig_sel wr_trig)
{
        struct idtcm *idtcm = channel->idtcm;
        u8 buf[TOD_BYTE_COUNT];
        u8 cmd;
        int err;
        struct timespec64 local_ts = *ts;
        s64 total_overhead_ns;

        /* Configure HW TOD write trigger. */
        err = idtcm_read(idtcm, channel->hw_dpll_n, HW_DPLL_TOD_CTRL_1,
                         &cmd, sizeof(cmd));
        if (err)
                return err;

        cmd &= ~(0x0f);
        cmd |= wr_trig | 0x08;

        err = idtcm_write(idtcm, channel->hw_dpll_n, HW_DPLL_TOD_CTRL_1,
                          &cmd, sizeof(cmd));
        if (err)
                return err;

        if (wr_trig  != HW_TOD_WR_TRIG_SEL_MSB) {
                err = timespec_to_char_array(&local_ts, buf, sizeof(buf));
                if (err)
                        return err;

                err = idtcm_write(idtcm, channel->hw_dpll_n,
                                  HW_DPLL_TOD_OVR__0, buf, sizeof(buf));
                if (err)
                        return err;
        }

        /* ARM HW TOD write trigger. */
        cmd &= ~(0x08);

        err = idtcm_write(idtcm, channel->hw_dpll_n, HW_DPLL_TOD_CTRL_1,
                          &cmd, sizeof(cmd));

        if (wr_trig == HW_TOD_WR_TRIG_SEL_MSB) {
                if (idtcm->calculate_overhead_flag) {
                        /* Assumption: I2C @ 400KHz */
                        ktime_t diff = ktime_sub(ktime_get_raw(),
                                                 idtcm->start_time);
                        total_overhead_ns =  ktime_to_ns(diff)
                                             + idtcm->tod_write_overhead_ns
                                             + SETTIME_CORRECTION;

                        timespec64_add_ns(&local_ts, total_overhead_ns);

                        idtcm->calculate_overhead_flag = 0;
                }

                err = timespec_to_char_array(&local_ts, buf, sizeof(buf));
                if (err)
                        return err;

                err = idtcm_write(idtcm, channel->hw_dpll_n,
                                  HW_DPLL_TOD_OVR__0, buf, sizeof(buf));
        }

        return err;
}

static int _idtcm_set_dpll_scsr_tod(struct idtcm_channel *channel,
                                    struct timespec64 const *ts,
                                    enum scsr_tod_write_trig_sel wr_trig,
                                    enum scsr_tod_write_type_sel wr_type)
{
        struct idtcm *idtcm = channel->idtcm;
        unsigned char buf[TOD_BYTE_COUNT], cmd;
        struct timespec64 local_ts = *ts;
        int err, count = 0;

        timespec64_add_ns(&local_ts, SETTIME_CORRECTION);

        err = timespec_to_char_array(&local_ts, buf, sizeof(buf));
        if (err)
                return err;

        err = idtcm_write(idtcm, channel->tod_write, TOD_WRITE,
                          buf, sizeof(buf));
        if (err)
                return err;

        /* Trigger the write operation. */
        err = idtcm_read(idtcm, channel->tod_write, TOD_WRITE_CMD,
                         &cmd, sizeof(cmd));
        if (err)
                return err;

        cmd &= ~(TOD_WRITE_SELECTION_MASK << TOD_WRITE_SELECTION_SHIFT);
        cmd &= ~(TOD_WRITE_TYPE_MASK << TOD_WRITE_TYPE_SHIFT);
        cmd |= (wr_trig << TOD_WRITE_SELECTION_SHIFT);
        cmd |= (wr_type << TOD_WRITE_TYPE_SHIFT);

        err = idtcm_write(idtcm, channel->tod_write, TOD_WRITE_CMD,
                           &cmd, sizeof(cmd));
        if (err)
                return err;

        /* Wait for the operation to complete. */
        while (1) {
                /* pps trigger takes up to 1 sec to complete */
                if (wr_trig == SCSR_TOD_WR_TRIG_SEL_TODPPS)
                        msleep(50);

                err = idtcm_read(idtcm, channel->tod_write, TOD_WRITE_CMD,
                                 &cmd, sizeof(cmd));
                if (err)
                        return err;

                if ((cmd & TOD_WRITE_SELECTION_MASK) == 0)
                        break;

                if (++count > 20) {
                        dev_err(idtcm->dev,
                                "Timed out waiting for the write counter");
                        return -EIO;
                }
        }

        return 0;
}

static int get_output_base_addr(enum fw_version ver, u8 outn)
{
        int base;

        switch (outn) {
        case 0:
                base = IDTCM_FW_REG(ver, V520, OUTPUT_0);
                break;
        case 1:
                base = IDTCM_FW_REG(ver, V520, OUTPUT_1);
                break;
        case 2:
                base = IDTCM_FW_REG(ver, V520, OUTPUT_2);
                break;
        case 3:
                base = IDTCM_FW_REG(ver, V520, OUTPUT_3);
                break;
        case 4:
                base = IDTCM_FW_REG(ver, V520, OUTPUT_4);
                break;
        case 5:
                base = IDTCM_FW_REG(ver, V520, OUTPUT_5);
                break;
        case 6:
                base = IDTCM_FW_REG(ver, V520, OUTPUT_6);
                break;
        case 7:
                base = IDTCM_FW_REG(ver, V520, OUTPUT_7);
                break;
        case 8:
                base = IDTCM_FW_REG(ver, V520, OUTPUT_8);
                break;
        case 9:
                base = IDTCM_FW_REG(ver, V520, OUTPUT_9);
                break;
        case 10:
                base = IDTCM_FW_REG(ver, V520, OUTPUT_10);
                break;
        case 11:
                base = IDTCM_FW_REG(ver, V520, OUTPUT_11);
                break;
        default:
                base = -EINVAL;
        }

        return base;
}

static int _idtcm_settime_deprecated(struct idtcm_channel *channel,
                                     struct timespec64 const *ts)
{
        struct idtcm *idtcm = channel->idtcm;
        int err;

        err = _idtcm_set_dpll_hw_tod(channel, ts, HW_TOD_WR_TRIG_SEL_MSB);
        if (err) {
                dev_err(idtcm->dev,
                        "%s: Set HW ToD failed", __func__);
                return err;
        }

        return idtcm_sync_pps_output(channel);
}

static int _idtcm_settime(struct idtcm_channel *channel,
                          struct timespec64 const *ts,
                          enum scsr_tod_write_type_sel wr_type)
{
        return _idtcm_set_dpll_scsr_tod(channel, ts,
                                        SCSR_TOD_WR_TRIG_SEL_IMMEDIATE,
                                        wr_type);
}

static int idtcm_set_phase_pull_in_offset(struct idtcm_channel *channel,
                                          s32 offset_ns)
{
        int err;
        int i;
        struct idtcm *idtcm = channel->idtcm;
        u8 buf[4];

        for (i = 0; i < 4; i++) {
                buf[i] = 0xff & (offset_ns);
                offset_ns >>= 8;
        }

        err = idtcm_write(idtcm, channel->dpll_phase_pull_in, PULL_IN_OFFSET,
                          buf, sizeof(buf));

        return err;
}

static int idtcm_set_phase_pull_in_slope_limit(struct idtcm_channel *channel,
                                               u32 max_ffo_ppb)
{
        int err;
        u8 i;
        struct idtcm *idtcm = channel->idtcm;
        u8 buf[3];

        if (max_ffo_ppb & 0xff000000)
                max_ffo_ppb = 0;

        for (i = 0; i < 3; i++) {
                buf[i] = 0xff & (max_ffo_ppb);
                max_ffo_ppb >>= 8;
        }

        err = idtcm_write(idtcm, channel->dpll_phase_pull_in,
                          PULL_IN_SLOPE_LIMIT, buf, sizeof(buf));

        return err;
}

static int idtcm_start_phase_pull_in(struct idtcm_channel *channel)
{
        int err;
        struct idtcm *idtcm = channel->idtcm;
        u8 buf;

        err = idtcm_read(idtcm, channel->dpll_phase_pull_in, PULL_IN_CTRL,
                         &buf, sizeof(buf));
        if (err)
                return err;

        if (buf == 0) {
                buf = 0x01;
                err = idtcm_write(idtcm, channel->dpll_phase_pull_in,
                                  PULL_IN_CTRL, &buf, sizeof(buf));
        } else {
                err = -EBUSY;
        }

        return err;
}

static int do_phase_pull_in_fw(struct idtcm_channel *channel,
                               s32 offset_ns,
                               u32 max_ffo_ppb)
{
        int err;

        err = idtcm_set_phase_pull_in_offset(channel, -offset_ns);
        if (err)
                return err;

        err = idtcm_set_phase_pull_in_slope_limit(channel, max_ffo_ppb);
        if (err)
                return err;

        err = idtcm_start_phase_pull_in(channel);

        return err;
}

static int set_tod_write_overhead(struct idtcm_channel *channel)
{
        struct idtcm *idtcm = channel->idtcm;
        s64 current_ns = 0;
        s64 lowest_ns = 0;
        int err;
        u8 i;
        ktime_t start;
        ktime_t stop;
        ktime_t diff;

        char buf[TOD_BYTE_COUNT] = {0};

        /* Set page offset */
        idtcm_write(idtcm, channel->hw_dpll_n, HW_DPLL_TOD_OVR__0,
                    buf, sizeof(buf));

        for (i = 0; i < TOD_WRITE_OVERHEAD_COUNT_MAX; i++) {
                start = ktime_get_raw();

                err = idtcm_write(idtcm, channel->hw_dpll_n,
                                  HW_DPLL_TOD_OVR__0, buf, sizeof(buf));
                if (err)
                        return err;

                stop = ktime_get_raw();

                diff = ktime_sub(stop, start);

                current_ns = ktime_to_ns(diff);

                if (i == 0) {
                        lowest_ns = current_ns;
                } else {
                        if (current_ns < lowest_ns)
                                lowest_ns = current_ns;
                }
        }

        idtcm->tod_write_overhead_ns = lowest_ns;

        return err;
}

static int _idtcm_adjtime_deprecated(struct idtcm_channel *channel, s64 delta)
{
        int err;
        struct idtcm *idtcm = channel->idtcm;
        struct timespec64 ts;
        s64 now;

        if (abs(delta) < PHASE_PULL_IN_THRESHOLD_NS_DEPRECATED) {
                err = channel->do_phase_pull_in(channel, delta, 0);
        } else {
                idtcm->calculate_overhead_flag = 1;

                err = set_tod_write_overhead(channel);
                if (err)
                        return err;

                err = _idtcm_gettime_immediate(channel, &ts);
                if (err)
                        return err;

                now = timespec64_to_ns(&ts);
                now += delta;

                ts = ns_to_timespec64(now);

                err = _idtcm_settime_deprecated(channel, &ts);
        }

        return err;
}

static int idtcm_state_machine_reset(struct idtcm *idtcm)
{
        u8 byte = SM_RESET_CMD;
        u32 status = 0;
        int err;
        u8 i;

        clear_boot_status(idtcm);

        err = idtcm_write(idtcm, RESET_CTRL,
                          IDTCM_FW_REG(idtcm->fw_ver, V520, SM_RESET),
                          &byte, sizeof(byte));

        if (!err) {
                for (i = 0; i < 30; i++) {
                        msleep_interruptible(100);
                        read_boot_status(idtcm, &status);

                        if (status == 0xA0) {
                                dev_dbg(idtcm->dev,
                                        "SM_RESET completed in %d ms", i * 100);
                                break;
                        }
                }

                if (!status)
                        dev_err(idtcm->dev,
                                "Timed out waiting for CM_RESET to complete");
        }

        return err;
}

static int idtcm_read_hw_rev_id(struct idtcm *idtcm, u8 *hw_rev_id)
{
        return idtcm_read(idtcm, HW_REVISION, REV_ID, hw_rev_id, sizeof(u8));
}

static int idtcm_read_product_id(struct idtcm *idtcm, u16 *product_id)
{
        int err;
        u8 buf[2] = {0};

        err = idtcm_read(idtcm, GENERAL_STATUS, PRODUCT_ID, buf, sizeof(buf));

        *product_id = (buf[1] << 8) | buf[0];

        return err;
}

static int idtcm_read_major_release(struct idtcm *idtcm, u8 *major)
{
        int err;
        u8 buf = 0;

        err = idtcm_read(idtcm, GENERAL_STATUS, MAJ_REL, &buf, sizeof(buf));

        *major = buf >> 1;

        return err;
}

static int idtcm_read_minor_release(struct idtcm *idtcm, u8 *minor)
{
        return idtcm_read(idtcm, GENERAL_STATUS, MIN_REL, minor, sizeof(u8));
}

static int idtcm_read_hotfix_release(struct idtcm *idtcm, u8 *hotfix)
{
        return idtcm_read(idtcm,
                          GENERAL_STATUS,
                          HOTFIX_REL,
                          hotfix,
                          sizeof(u8));
}

static int idtcm_read_otp_scsr_config_select(struct idtcm *idtcm,
                                             u8 *config_select)
{
        return idtcm_read(idtcm, GENERAL_STATUS, OTP_SCSR_CONFIG_SELECT,
                          config_select, sizeof(u8));
}

static int set_pll_output_mask(struct idtcm *idtcm, u16 addr, u8 val)
{
        int err = 0;

        switch (addr) {
        case TOD0_OUT_ALIGN_MASK_ADDR:
                SET_U16_LSB(idtcm->channel[0].output_mask, val);
                break;
        case TOD0_OUT_ALIGN_MASK_ADDR + 1:
                SET_U16_MSB(idtcm->channel[0].output_mask, val);
                break;
        case TOD1_OUT_ALIGN_MASK_ADDR:
                SET_U16_LSB(idtcm->channel[1].output_mask, val);
                break;
        case TOD1_OUT_ALIGN_MASK_ADDR + 1:
                SET_U16_MSB(idtcm->channel[1].output_mask, val);
                break;
        case TOD2_OUT_ALIGN_MASK_ADDR:
                SET_U16_LSB(idtcm->channel[2].output_mask, val);
                break;
        case TOD2_OUT_ALIGN_MASK_ADDR + 1:
                SET_U16_MSB(idtcm->channel[2].output_mask, val);
                break;
        case TOD3_OUT_ALIGN_MASK_ADDR:
                SET_U16_LSB(idtcm->channel[3].output_mask, val);
                break;
        case TOD3_OUT_ALIGN_MASK_ADDR + 1:
                SET_U16_MSB(idtcm->channel[3].output_mask, val);
                break;
        default:
                err = -EFAULT; /* Bad address */
                break;
        }

        return err;
}

static int set_tod_ptp_pll(struct idtcm *idtcm, u8 index, u8 pll)
{
        if (index >= MAX_TOD) {
                dev_err(idtcm->dev, "ToD%d not supported", index);
                return -EINVAL;
        }

        if (pll >= MAX_PLL) {
                dev_err(idtcm->dev, "Pll%d not supported", pll);
                return -EINVAL;
        }

        idtcm->channel[index].pll = pll;

        return 0;
}

static int check_and_set_masks(struct idtcm *idtcm,
                               u16 regaddr,
                               u8 val)
{
        int err = 0;

        switch (regaddr) {
        case TOD_MASK_ADDR:
                if ((val & 0xf0) || !(val & 0x0f)) {
                        dev_err(idtcm->dev, "Invalid TOD mask 0x%02x", val);
                        err = -EINVAL;
                } else {
                        idtcm->tod_mask = val;
                }
                break;
        case TOD0_PTP_PLL_ADDR:
                err = set_tod_ptp_pll(idtcm, 0, val);
                break;
        case TOD1_PTP_PLL_ADDR:
                err = set_tod_ptp_pll(idtcm, 1, val);
                break;
        case TOD2_PTP_PLL_ADDR:
                err = set_tod_ptp_pll(idtcm, 2, val);
                break;
        case TOD3_PTP_PLL_ADDR:
                err = set_tod_ptp_pll(idtcm, 3, val);
                break;
        default:
                err = set_pll_output_mask(idtcm, regaddr, val);
                break;
        }

        return err;
}

static void display_pll_and_masks(struct idtcm *idtcm)
{
        u8 i;
        u8 mask;

        dev_dbg(idtcm->dev, "tod_mask = 0x%02x", idtcm->tod_mask);

        for (i = 0; i < MAX_TOD; i++) {
                mask = 1 << i;

                if (mask & idtcm->tod_mask)
                        dev_dbg(idtcm->dev,
                                "TOD%d pll = %d    output_mask = 0x%04x",
                                i, idtcm->channel[i].pll,
                                idtcm->channel[i].output_mask);
        }
}

static int idtcm_load_firmware(struct idtcm *idtcm,
                               struct device *dev)
{
        u16 scratch = IDTCM_FW_REG(idtcm->fw_ver, V520, SCRATCH);
        char fname[128] = FW_FILENAME;
        const struct firmware *fw;
        struct idtcm_fwrc *rec;
        u32 regaddr;
        int err;
        s32 len;
        u8 val;
        u8 loaddr;

        if (firmware) /* module parameter */
                snprintf(fname, sizeof(fname), "%s", firmware);

        dev_info(idtcm->dev, "requesting firmware '%s'", fname);

        err = request_firmware(&fw, fname, dev);
        if (err) {
                dev_err(idtcm->dev,
                        "Failed at line %d in %s!", __LINE__, __func__);
                return err;
        }

        dev_dbg(idtcm->dev, "firmware size %zu bytes", fw->size);

        rec = (struct idtcm_fwrc *) fw->data;

        if (contains_full_configuration(idtcm, fw))
                idtcm_state_machine_reset(idtcm);

        for (len = fw->size; len > 0; len -= sizeof(*rec)) {
                if (rec->reserved) {
                        dev_err(idtcm->dev,
                                "bad firmware, reserved field non-zero");
                        err = -EINVAL;
                } else {
                        regaddr = rec->hiaddr << 8;
                        regaddr |= rec->loaddr;

                        val = rec->value;
                        loaddr = rec->loaddr;

                        rec++;

                        err = check_and_set_masks(idtcm, regaddr, val);
                }

                if (err != -EINVAL) {
                        err = 0;

                        /* Top (status registers) and bottom are read-only */
                        if (regaddr < GPIO_USER_CONTROL || regaddr >= scratch)
                                continue;

                        /* Page size 128, last 4 bytes of page skipped */
                        if ((loaddr > 0x7b && loaddr <= 0x7f) || loaddr > 0xfb)
                                continue;

                        err = idtcm_write(idtcm, regaddr, 0, &val, sizeof(val));
                }

                if (err)
                        goto out;
        }

        display_pll_and_masks(idtcm);

out:
        release_firmware(fw);
        return err;
}

static int idtcm_output_enable(struct idtcm_channel *channel,
                               bool enable, unsigned int outn)
{
        struct idtcm *idtcm = channel->idtcm;
        int base;
        int err;
        u8 val;

        base = get_output_base_addr(idtcm->fw_ver, outn);

        if (!(base > 0)) {
                dev_err(idtcm->dev,
                        "%s - Unsupported out%d", __func__, outn);
                return base;
        }

        err = idtcm_read(idtcm, (u16)base, OUT_CTRL_1, &val, sizeof(val));
        if (err)
                return err;

        if (enable)
                val |= SQUELCH_DISABLE;
        else
                val &= ~SQUELCH_DISABLE;

        return idtcm_write(idtcm, (u16)base, OUT_CTRL_1, &val, sizeof(val));
}

static int idtcm_perout_enable(struct idtcm_channel *channel,
                               struct ptp_perout_request *perout,
                               bool enable)
{
        struct idtcm *idtcm = channel->idtcm;
        struct timespec64 ts = {0, 0};
        int err;

        err = idtcm_output_enable(channel, enable, perout->index);

        if (err) {
                dev_err(idtcm->dev, "Unable to set output enable");
                return err;
        }

        /* Align output to internal 1 PPS */
        return _idtcm_settime(channel, &ts, SCSR_TOD_WR_TYPE_SEL_DELTA_PLUS);
}

static int idtcm_get_pll_mode(struct idtcm_channel *channel,
                              enum pll_mode *mode)
{
        struct idtcm *idtcm = channel->idtcm;
        int err;
        u8 dpll_mode;

        err = idtcm_read(idtcm, channel->dpll_n,
                         IDTCM_FW_REG(idtcm->fw_ver, V520, DPLL_MODE),
                         &dpll_mode, sizeof(dpll_mode));
        if (err)
                return err;

        *mode = (dpll_mode >> PLL_MODE_SHIFT) & PLL_MODE_MASK;

        return 0;
}

static int idtcm_set_pll_mode(struct idtcm_channel *channel,
                              enum pll_mode mode)
{
        struct idtcm *idtcm = channel->idtcm;
        int err;
        u8 dpll_mode;

        err = idtcm_read(idtcm, channel->dpll_n,
                         IDTCM_FW_REG(idtcm->fw_ver, V520, DPLL_MODE),
                         &dpll_mode, sizeof(dpll_mode));
        if (err)
                return err;

        dpll_mode &= ~(PLL_MODE_MASK << PLL_MODE_SHIFT);

        dpll_mode |= (mode << PLL_MODE_SHIFT);

        err = idtcm_write(idtcm, channel->dpll_n,
                          IDTCM_FW_REG(idtcm->fw_ver, V520, DPLL_MODE),
                          &dpll_mode, sizeof(dpll_mode));
        return err;
}

static int idtcm_get_manual_reference(struct idtcm_channel *channel,
                                      enum manual_reference *ref)
{
        struct idtcm *idtcm = channel->idtcm;
        u8 dpll_manu_ref_cfg;
        int err;

        err = idtcm_read(idtcm, channel->dpll_ctrl_n,
                         DPLL_CTRL_DPLL_MANU_REF_CFG,
                         &dpll_manu_ref_cfg, sizeof(dpll_manu_ref_cfg));
        if (err)
                return err;

        dpll_manu_ref_cfg &= (MANUAL_REFERENCE_MASK << MANUAL_REFERENCE_SHIFT);

        *ref = dpll_manu_ref_cfg >> MANUAL_REFERENCE_SHIFT;

        return 0;
}

static int idtcm_set_manual_reference(struct idtcm_channel *channel,
                                      enum manual_reference ref)
{
        struct idtcm *idtcm = channel->idtcm;
        u8 dpll_manu_ref_cfg;
        int err;

        err = idtcm_read(idtcm, channel->dpll_ctrl_n,
                         DPLL_CTRL_DPLL_MANU_REF_CFG,
                         &dpll_manu_ref_cfg, sizeof(dpll_manu_ref_cfg));
        if (err)
                return err;

        dpll_manu_ref_cfg &= ~(MANUAL_REFERENCE_MASK << MANUAL_REFERENCE_SHIFT);

        dpll_manu_ref_cfg |= (ref << MANUAL_REFERENCE_SHIFT);

        err = idtcm_write(idtcm, channel->dpll_ctrl_n,
                          DPLL_CTRL_DPLL_MANU_REF_CFG,
                          &dpll_manu_ref_cfg, sizeof(dpll_manu_ref_cfg));

        return err;
}

static int configure_dpll_mode_write_frequency(struct idtcm_channel *channel)
{
        struct idtcm *idtcm = channel->idtcm;
        int err;

        err = idtcm_set_pll_mode(channel, PLL_MODE_WRITE_FREQUENCY);

        if (err)
                dev_err(idtcm->dev, "Failed to set pll mode to write frequency");
        else
                channel->mode = PTP_PLL_MODE_WRITE_FREQUENCY;

        return err;
}

static int configure_dpll_mode_write_phase(struct idtcm_channel *channel)
{
        struct idtcm *idtcm = channel->idtcm;
        int err;

        err = idtcm_set_pll_mode(channel, PLL_MODE_WRITE_PHASE);

        if (err)
                dev_err(idtcm->dev, "Failed to set pll mode to write phase");
        else
                channel->mode = PTP_PLL_MODE_WRITE_PHASE;

        return err;
}

static int configure_manual_reference_write_frequency(struct idtcm_channel *channel)
{
        struct idtcm *idtcm = channel->idtcm;
        int err;

        err = idtcm_set_manual_reference(channel, MANU_REF_WRITE_FREQUENCY);

        if (err)
                dev_err(idtcm->dev, "Failed to set manual reference to write frequency");
        else
                channel->mode = PTP_PLL_MODE_WRITE_FREQUENCY;

        return err;
}

static int configure_manual_reference_write_phase(struct idtcm_channel *channel)
{
        struct idtcm *idtcm = channel->idtcm;
        int err;

        err = idtcm_set_manual_reference(channel, MANU_REF_WRITE_PHASE);

        if (err)
                dev_err(idtcm->dev, "Failed to set manual reference to write phase");
        else
                channel->mode = PTP_PLL_MODE_WRITE_PHASE;

        return err;
}

static int idtcm_stop_phase_pull_in(struct idtcm_channel *channel)
{
        int err;

        err = _idtcm_adjfine(channel, channel->current_freq_scaled_ppm);
        if (err)
                return err;

        channel->phase_pull_in = false;

        return 0;
}

static long idtcm_work_handler(struct ptp_clock_info *ptp)
{
        struct idtcm_channel *channel = container_of(ptp, struct idtcm_channel, caps);
        struct idtcm *idtcm = channel->idtcm;

        mutex_lock(idtcm->lock);

        (void)idtcm_stop_phase_pull_in(channel);

        mutex_unlock(idtcm->lock);

        /* Return a negative value here to not reschedule */
        return -1;
}

static s32 phase_pull_in_scaled_ppm(s32 current_ppm, s32 phase_pull_in_ppb)
{
        /* ppb = scaled_ppm * 125 / 2^13 */
        /* scaled_ppm = ppb * 2^13 / 125 */

        s64 max_scaled_ppm = div_s64((s64)PHASE_PULL_IN_MAX_PPB << 13, 125);
        s64 scaled_ppm = div_s64((s64)phase_pull_in_ppb << 13, 125);

        current_ppm += scaled_ppm;

        if (current_ppm > max_scaled_ppm)
                current_ppm = max_scaled_ppm;
        else if (current_ppm < -max_scaled_ppm)
                current_ppm = -max_scaled_ppm;

        return current_ppm;
}

static int do_phase_pull_in_sw(struct idtcm_channel *channel,
                               s32 delta_ns,
                               u32 max_ffo_ppb)
{
        s32 current_ppm = channel->current_freq_scaled_ppm;
        u32 duration_ms = MSEC_PER_SEC;
        s32 delta_ppm;
        s32 ppb;
        int err;

        /* If the ToD correction is less than PHASE_PULL_IN_MIN_THRESHOLD_NS,
         * skip. The error introduced by the ToD adjustment procedure would
         * be bigger than the required ToD correction
         */
        if (abs(delta_ns) < PHASE_PULL_IN_MIN_THRESHOLD_NS)
                return 0;

        if (max_ffo_ppb == 0)
                max_ffo_ppb = PHASE_PULL_IN_MAX_PPB;

        /* For most cases, keep phase pull-in duration 1 second */
        ppb = delta_ns;
        while (abs(ppb) > max_ffo_ppb) {
                duration_ms *= 2;
                ppb /= 2;
        }

        delta_ppm = phase_pull_in_scaled_ppm(current_ppm, ppb);

        err = _idtcm_adjfine(channel, delta_ppm);

        if (err)
                return err;

        /* schedule the worker to cancel phase pull-in */
        ptp_schedule_worker(channel->ptp_clock,
                            msecs_to_jiffies(duration_ms) - 1);

        channel->phase_pull_in = true;

        return 0;
}

static int initialize_operating_mode_with_manual_reference(struct idtcm_channel *channel,
                                                           enum manual_reference ref)
{
        struct idtcm *idtcm = channel->idtcm;

        channel->mode = PTP_PLL_MODE_UNSUPPORTED;
        channel->configure_write_frequency = configure_manual_reference_write_frequency;
        channel->configure_write_phase = configure_manual_reference_write_phase;
        channel->do_phase_pull_in = do_phase_pull_in_sw;

        switch (ref) {
        case MANU_REF_WRITE_PHASE:
                channel->mode = PTP_PLL_MODE_WRITE_PHASE;
                break;
        case MANU_REF_WRITE_FREQUENCY:
                channel->mode = PTP_PLL_MODE_WRITE_FREQUENCY;
                break;
        default:
                dev_warn(idtcm->dev,
                         "Unsupported MANUAL_REFERENCE: 0x%02x", ref);
        }

        return 0;
}

static int initialize_operating_mode_with_pll_mode(struct idtcm_channel *channel,
                                                   enum pll_mode mode)
{
        struct idtcm *idtcm = channel->idtcm;
        int err = 0;

        channel->mode = PTP_PLL_MODE_UNSUPPORTED;
        channel->configure_write_frequency = configure_dpll_mode_write_frequency;
        channel->configure_write_phase = configure_dpll_mode_write_phase;
        channel->do_phase_pull_in = do_phase_pull_in_fw;

        switch (mode) {
        case  PLL_MODE_WRITE_PHASE:
                channel->mode = PTP_PLL_MODE_WRITE_PHASE;
                break;
        case PLL_MODE_WRITE_FREQUENCY:
                channel->mode = PTP_PLL_MODE_WRITE_FREQUENCY;
                break;
        default:
                dev_err(idtcm->dev,
                        "Unsupported PLL_MODE: 0x%02x", mode);
                err = -EINVAL;
        }

        return err;
}

static int initialize_dco_operating_mode(struct idtcm_channel *channel)
{
        enum manual_reference ref = MANU_REF_XO_DPLL;
        enum pll_mode mode = PLL_MODE_DISABLED;
        struct idtcm *idtcm = channel->idtcm;
        int err;

        channel->mode = PTP_PLL_MODE_UNSUPPORTED;

        err = idtcm_get_pll_mode(channel, &mode);
        if (err) {
                dev_err(idtcm->dev, "Unable to read pll mode!");
                return err;
        }

        if (mode == PLL_MODE_PLL) {
                err = idtcm_get_manual_reference(channel, &ref);
                if (err) {
                        dev_err(idtcm->dev, "Unable to read manual reference!");
                        return err;
                }
                err = initialize_operating_mode_with_manual_reference(channel, ref);
        } else {
                err = initialize_operating_mode_with_pll_mode(channel, mode);
        }

        if (channel->mode == PTP_PLL_MODE_WRITE_PHASE)
                channel->configure_write_frequency(channel);

        return err;
}

/* PTP Hardware Clock interface */

/*
 * Maximum absolute value for write phase offset in nanoseconds
 *
 * Destination signed register is 32-bit register in resolution of 50ps
 *
 * 0x7fffffff * 50 =  2147483647 * 50 = 107374182350 ps
 * Represent 107374182350 ps as 107374182 ns
 */
static s32 idtcm_getmaxphase(struct ptp_clock_info *ptp __always_unused)
{
        return MAX_ABS_WRITE_PHASE_NANOSECONDS;
}

/*
 * Internal function for implementing support for write phase offset
 *
 * @channel:  channel
 * @delta_ns: delta in nanoseconds
 */
static int _idtcm_adjphase(struct idtcm_channel *channel, s32 delta_ns)
{
        struct idtcm *idtcm = channel->idtcm;
        int err;
        u8 i;
        u8 buf[4] = {0};
        s32 phase_50ps;

        if (channel->mode != PTP_PLL_MODE_WRITE_PHASE) {
                err = channel->configure_write_phase(channel);
                if (err)
                        return err;
        }

        phase_50ps = div_s64((s64)delta_ns * 1000, 50);

        for (i = 0; i < 4; i++) {
                buf[i] = phase_50ps & 0xff;
                phase_50ps >>= 8;
        }

        err = idtcm_write(idtcm, channel->dpll_phase, DPLL_WR_PHASE,
                          buf, sizeof(buf));

        return err;
}

static int _idtcm_adjfine(struct idtcm_channel *channel, long scaled_ppm)
{
        struct idtcm *idtcm = channel->idtcm;
        u8 i;
        int err;
        u8 buf[6] = {0};
        s64 fcw;

        if (channel->mode  != PTP_PLL_MODE_WRITE_FREQUENCY) {
                err = channel->configure_write_frequency(channel);
                if (err)
                        return err;
        }

        /*
         * Frequency Control Word unit is: 1.11 * 10^-10 ppm
         *
         * adjfreq:
         *       ppb * 10^9
         * FCW = ----------
         *          111
         *
         * adjfine:
         *       ppm_16 * 5^12
         * FCW = -------------
         *         111 * 2^4
         */

        /* 2 ^ -53 = 1.1102230246251565404236316680908e-16 */
        fcw = scaled_ppm * 244140625ULL;

        fcw = div_s64(fcw, 1776);

        for (i = 0; i < 6; i++) {
                buf[i] = fcw & 0xff;
                fcw >>= 8;
        }

        err = idtcm_write(idtcm, channel->dpll_freq, DPLL_WR_FREQ,
                          buf, sizeof(buf));

        return err;
}

static int idtcm_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
{
        struct idtcm_channel *channel = container_of(ptp, struct idtcm_channel, caps);
        struct idtcm *idtcm = channel->idtcm;
        int err;

        mutex_lock(idtcm->lock);
        err = _idtcm_gettime_immediate(channel, ts);
        mutex_unlock(idtcm->lock);

        if (err)
                dev_err(idtcm->dev, "Failed at line %d in %s!",
                        __LINE__, __func__);

        return err;
}

static int idtcm_settime_deprecated(struct ptp_clock_info *ptp,
                                    const struct timespec64 *ts)
{
        struct idtcm_channel *channel = container_of(ptp, struct idtcm_channel, caps);
        struct idtcm *idtcm = channel->idtcm;
        int err;

        mutex_lock(idtcm->lock);
        err = _idtcm_settime_deprecated(channel, ts);
        mutex_unlock(idtcm->lock);

        if (err)
                dev_err(idtcm->dev,
                        "Failed at line %d in %s!", __LINE__, __func__);

        return err;
}

static int idtcm_settime(struct ptp_clock_info *ptp,
                         const struct timespec64 *ts)
{
        struct idtcm_channel *channel = container_of(ptp, struct idtcm_channel, caps);
        struct idtcm *idtcm = channel->idtcm;
        int err;

        mutex_lock(idtcm->lock);
        err = _idtcm_settime(channel, ts, SCSR_TOD_WR_TYPE_SEL_ABSOLUTE);
        mutex_unlock(idtcm->lock);

        if (err)
                dev_err(idtcm->dev,
                        "Failed at line %d in %s!", __LINE__, __func__);

        return err;
}

static int idtcm_adjtime_deprecated(struct ptp_clock_info *ptp, s64 delta)
{
        struct idtcm_channel *channel = container_of(ptp, struct idtcm_channel, caps);
        struct idtcm *idtcm = channel->idtcm;
        int err;

        mutex_lock(idtcm->lock);
        err = _idtcm_adjtime_deprecated(channel, delta);
        mutex_unlock(idtcm->lock);

        if (err)
                dev_err(idtcm->dev,
                        "Failed at line %d in %s!", __LINE__, __func__);

        return err;
}

static int idtcm_adjtime(struct ptp_clock_info *ptp, s64 delta)
{
        struct idtcm_channel *channel = container_of(ptp, struct idtcm_channel, caps);
        struct idtcm *idtcm = channel->idtcm;
        struct timespec64 ts;
        enum scsr_tod_write_type_sel type;
        int err;

        if (channel->phase_pull_in == true)
                return -EBUSY;

        mutex_lock(idtcm->lock);

        if (abs(delta) < PHASE_PULL_IN_THRESHOLD_NS) {
                err = channel->do_phase_pull_in(channel, delta, 0);
        } else {
                if (delta >= 0) {
                        ts = ns_to_timespec64(delta);
                        type = SCSR_TOD_WR_TYPE_SEL_DELTA_PLUS;
                } else {
                        ts = ns_to_timespec64(-delta);
                        type = SCSR_TOD_WR_TYPE_SEL_DELTA_MINUS;
                }
                err = _idtcm_settime(channel, &ts, type);
        }

        mutex_unlock(idtcm->lock);

        if (err)
                dev_err(idtcm->dev,
                        "Failed at line %d in %s!", __LINE__, __func__);

        return err;
}

static int idtcm_adjphase(struct ptp_clock_info *ptp, s32 delta)
{
        struct idtcm_channel *channel = container_of(ptp, struct idtcm_channel, caps);
        struct idtcm *idtcm = channel->idtcm;
        int err;

        mutex_lock(idtcm->lock);
        err = _idtcm_adjphase(channel, delta);
        mutex_unlock(idtcm->lock);

        if (err)
                dev_err(idtcm->dev,
                        "Failed at line %d in %s!", __LINE__, __func__);

        return err;
}

static int idtcm_adjfine(struct ptp_clock_info *ptp,  long scaled_ppm)
{
        struct idtcm_channel *channel = container_of(ptp, struct idtcm_channel, caps);
        struct idtcm *idtcm = channel->idtcm;
        int err;

        if (channel->phase_pull_in == true)
                return 0;

        if (scaled_ppm == channel->current_freq_scaled_ppm)
                return 0;

        mutex_lock(idtcm->lock);
        err = _idtcm_adjfine(channel, scaled_ppm);
        mutex_unlock(idtcm->lock);

        if (err)
                dev_err(idtcm->dev,
                        "Failed at line %d in %s!", __LINE__, __func__);
        else
                channel->current_freq_scaled_ppm = scaled_ppm;

        return err;
}

static int idtcm_enable(struct ptp_clock_info *ptp,
                        struct ptp_clock_request *rq, int on)
{
        struct idtcm_channel *channel = container_of(ptp, struct idtcm_channel, caps);
        struct idtcm *idtcm = channel->idtcm;
        int err = -EOPNOTSUPP;

        mutex_lock(idtcm->lock);

        switch (rq->type) {
        case PTP_CLK_REQ_PEROUT:
                if (!on)
                        err = idtcm_perout_enable(channel, &rq->perout, false);
                /* Only accept a 1-PPS aligned to the second. */
                else if (rq->perout.start.nsec || rq->perout.period.sec != 1 ||
                         rq->perout.period.nsec)
                        err = -ERANGE;
                else
                        err = idtcm_perout_enable(channel, &rq->perout, true);
                break;
        case PTP_CLK_REQ_EXTTS:
                err = idtcm_extts_enable(channel, rq, on);
                break;
        default:
                break;
        }

        mutex_unlock(idtcm->lock);

        if (err)
                dev_err(channel->idtcm->dev,
                        "Failed in %s with err %d!", __func__, err);

        return err;
}

static int idtcm_enable_tod(struct idtcm_channel *channel)
{
        struct idtcm *idtcm = channel->idtcm;
        struct timespec64 ts = {0, 0};
        u16 tod_cfg = IDTCM_FW_REG(idtcm->fw_ver, V520, TOD_CFG);
        u8 cfg;
        int err;

        /*
         * Start the TOD clock ticking.
         */
        err = idtcm_read(idtcm, channel->tod_n, tod_cfg, &cfg, sizeof(cfg));
        if (err)
                return err;

        cfg |= TOD_ENABLE;

        err = idtcm_write(idtcm, channel->tod_n, tod_cfg, &cfg, sizeof(cfg));
        if (err)
                return err;

        if (idtcm->fw_ver < V487)
                return _idtcm_settime_deprecated(channel, &ts);
        else
                return _idtcm_settime(channel, &ts,
                                      SCSR_TOD_WR_TYPE_SEL_ABSOLUTE);
}

static void idtcm_set_version_info(struct idtcm *idtcm)
{
        u8 major;
        u8 minor;
        u8 hotfix;
        u16 product_id;
        u8 hw_rev_id;
        u8 config_select;

        idtcm_read_major_release(idtcm, &major);
        idtcm_read_minor_release(idtcm, &minor);
        idtcm_read_hotfix_release(idtcm, &hotfix);

        idtcm_read_product_id(idtcm, &product_id);
        idtcm_read_hw_rev_id(idtcm, &hw_rev_id);

        idtcm_read_otp_scsr_config_select(idtcm, &config_select);

        snprintf(idtcm->version, sizeof(idtcm->version), "%u.%u.%u",
                 major, minor, hotfix);

        idtcm->fw_ver = idtcm_fw_version(idtcm->version);

        dev_info(idtcm->dev,
                 "%d.%d.%d, Id: 0x%04x  HW Rev: %d  OTP Config Select: %d",
                 major, minor, hotfix,
                 product_id, hw_rev_id, config_select);
}

static int idtcm_verify_pin(struct ptp_clock_info *ptp, unsigned int pin,
                            enum ptp_pin_function func, unsigned int chan)
{
        switch (func) {
        case PTP_PF_NONE:
        case PTP_PF_EXTTS:
                break;
        case PTP_PF_PEROUT:
        case PTP_PF_PHYSYNC:
                return -1;
        }
        return 0;
}

static struct ptp_pin_desc pin_config[MAX_TOD][MAX_REF_CLK];

static const struct ptp_clock_info idtcm_caps = {
        .owner          = THIS_MODULE,
        .max_adj        = 244000,
        .n_per_out      = 12,
        .n_ext_ts       = MAX_TOD,
        .n_pins         = MAX_REF_CLK,
        .supported_extts_flags = PTP_RISING_EDGE | PTP_STRICT_FLAGS,
        .adjphase       = &idtcm_adjphase,
        .getmaxphase    = &idtcm_getmaxphase,
        .adjfine        = &idtcm_adjfine,
        .adjtime        = &idtcm_adjtime,
        .gettime64      = &idtcm_gettime,
        .settime64      = &idtcm_settime,
        .enable         = &idtcm_enable,
        .verify         = &idtcm_verify_pin,
        .do_aux_work    = &idtcm_work_handler,
};

static const struct ptp_clock_info idtcm_caps_deprecated = {
        .owner          = THIS_MODULE,
        .max_adj        = 244000,
        .n_per_out      = 12,
        .n_ext_ts       = MAX_TOD,
        .n_pins         = MAX_REF_CLK,
        .supported_extts_flags = PTP_RISING_EDGE | PTP_STRICT_FLAGS,
        .adjphase       = &idtcm_adjphase,
        .getmaxphase    = &idtcm_getmaxphase,
        .adjfine        = &idtcm_adjfine,
        .adjtime        = &idtcm_adjtime_deprecated,
        .gettime64      = &idtcm_gettime,
        .settime64      = &idtcm_settime_deprecated,
        .enable         = &idtcm_enable,
        .verify         = &idtcm_verify_pin,
        .do_aux_work    = &idtcm_work_handler,
};

static int configure_channel_pll(struct idtcm_channel *channel)
{
        struct idtcm *idtcm = channel->idtcm;
        int err = 0;

        switch (channel->pll) {
        case 0:
                channel->dpll_freq = DPLL_FREQ_0;
                channel->dpll_n = DPLL_0;
                channel->hw_dpll_n = HW_DPLL_0;
                channel->dpll_phase = DPLL_PHASE_0;
                channel->dpll_ctrl_n = DPLL_CTRL_0;
                channel->dpll_phase_pull_in = DPLL_PHASE_PULL_IN_0;
                break;
        case 1:
                channel->dpll_freq = DPLL_FREQ_1;
                channel->dpll_n = DPLL_1;
                channel->hw_dpll_n = HW_DPLL_1;
                channel->dpll_phase = DPLL_PHASE_1;
                channel->dpll_ctrl_n = DPLL_CTRL_1;
                channel->dpll_phase_pull_in = DPLL_PHASE_PULL_IN_1;
                break;
        case 2:
                channel->dpll_freq = DPLL_FREQ_2;
                channel->dpll_n = IDTCM_FW_REG(idtcm->fw_ver, V520, DPLL_2);
                channel->hw_dpll_n = HW_DPLL_2;
                channel->dpll_phase = DPLL_PHASE_2;
                channel->dpll_ctrl_n = DPLL_CTRL_2;
                channel->dpll_phase_pull_in = DPLL_PHASE_PULL_IN_2;
                break;
        case 3:
                channel->dpll_freq = DPLL_FREQ_3;
                channel->dpll_n = DPLL_3;
                channel->hw_dpll_n = HW_DPLL_3;
                channel->dpll_phase = DPLL_PHASE_3;
                channel->dpll_ctrl_n = DPLL_CTRL_3;
                channel->dpll_phase_pull_in = DPLL_PHASE_PULL_IN_3;
                break;
        case 4:
                channel->dpll_freq = DPLL_FREQ_4;
                channel->dpll_n = IDTCM_FW_REG(idtcm->fw_ver, V520, DPLL_4);
                channel->hw_dpll_n = HW_DPLL_4;
                channel->dpll_phase = DPLL_PHASE_4;
                channel->dpll_ctrl_n = DPLL_CTRL_4;
                channel->dpll_phase_pull_in = DPLL_PHASE_PULL_IN_4;
                break;
        case 5:
                channel->dpll_freq = DPLL_FREQ_5;
                channel->dpll_n = DPLL_5;
                channel->hw_dpll_n = HW_DPLL_5;
                channel->dpll_phase = DPLL_PHASE_5;
                channel->dpll_ctrl_n = DPLL_CTRL_5;
                channel->dpll_phase_pull_in = DPLL_PHASE_PULL_IN_5;
                break;
        case 6:
                channel->dpll_freq = DPLL_FREQ_6;
                channel->dpll_n = IDTCM_FW_REG(idtcm->fw_ver, V520, DPLL_6);
                channel->hw_dpll_n = HW_DPLL_6;
                channel->dpll_phase = DPLL_PHASE_6;
                channel->dpll_ctrl_n = DPLL_CTRL_6;
                channel->dpll_phase_pull_in = DPLL_PHASE_PULL_IN_6;
                break;
        case 7:
                channel->dpll_freq = DPLL_FREQ_7;
                channel->dpll_n = DPLL_7;
                channel->hw_dpll_n = HW_DPLL_7;
                channel->dpll_phase = DPLL_PHASE_7;
                channel->dpll_ctrl_n = DPLL_CTRL_7;
                channel->dpll_phase_pull_in = DPLL_PHASE_PULL_IN_7;
                break;
        default:
                err = -EINVAL;
        }

        return err;
}

/*
 * Compensate for the PTP DCO input-to-output delay.
 * This delay is 18 FOD cycles.
 */
static u32 idtcm_get_dco_delay(struct idtcm_channel *channel)
{
        struct idtcm *idtcm = channel->idtcm;
        u8 mbuf[8] = {0};
        u8 nbuf[2] = {0};
        u32 fodFreq;
        int err;
        u64 m;
        u16 n;

        err = idtcm_read(idtcm, channel->dpll_ctrl_n,
                         DPLL_CTRL_DPLL_FOD_FREQ, mbuf, 6);
        if (err)
                return 0;

        err = idtcm_read(idtcm, channel->dpll_ctrl_n,
                         DPLL_CTRL_DPLL_FOD_FREQ + 6, nbuf, 2);
        if (err)
                return 0;

        m = get_unaligned_le64(mbuf);
        n = get_unaligned_le16(nbuf);

        if (n == 0)
                n = 1;

        fodFreq = (u32)div_u64(m, n);

        if (fodFreq >= 500000000)
                return (u32)div_u64(18 * (u64)NSEC_PER_SEC, fodFreq);

        return 0;
}

static int configure_channel_tod(struct idtcm_channel *channel, u32 index)
{
        enum fw_version fw_ver = channel->idtcm->fw_ver;

        /* Set tod addresses */
        switch (index) {
        case 0:
                channel->tod_read_primary = IDTCM_FW_REG(fw_ver, V520, TOD_READ_PRIMARY_0);
                channel->tod_read_secondary = IDTCM_FW_REG(fw_ver, V520, TOD_READ_SECONDARY_0);
                channel->tod_write = IDTCM_FW_REG(fw_ver, V520, TOD_WRITE_0);
                channel->tod_n = IDTCM_FW_REG(fw_ver, V520, TOD_0);
                channel->sync_src = SYNC_SOURCE_DPLL0_TOD_PPS;
                break;
        case 1:
                channel->tod_read_primary = IDTCM_FW_REG(fw_ver, V520, TOD_READ_PRIMARY_1);
                channel->tod_read_secondary = IDTCM_FW_REG(fw_ver, V520, TOD_READ_SECONDARY_1);
                channel->tod_write = IDTCM_FW_REG(fw_ver, V520, TOD_WRITE_1);
                channel->tod_n = IDTCM_FW_REG(fw_ver, V520, TOD_1);
                channel->sync_src = SYNC_SOURCE_DPLL1_TOD_PPS;
                break;
        case 2:
                channel->tod_read_primary = IDTCM_FW_REG(fw_ver, V520, TOD_READ_PRIMARY_2);
                channel->tod_read_secondary = IDTCM_FW_REG(fw_ver, V520, TOD_READ_SECONDARY_2);
                channel->tod_write = IDTCM_FW_REG(fw_ver, V520, TOD_WRITE_2);
                channel->tod_n = IDTCM_FW_REG(fw_ver, V520, TOD_2);
                channel->sync_src = SYNC_SOURCE_DPLL2_TOD_PPS;
                break;
        case 3:
                channel->tod_read_primary = IDTCM_FW_REG(fw_ver, V520, TOD_READ_PRIMARY_3);
                channel->tod_read_secondary = IDTCM_FW_REG(fw_ver, V520, TOD_READ_SECONDARY_3);
                channel->tod_write = IDTCM_FW_REG(fw_ver, V520, TOD_WRITE_3);
                channel->tod_n = IDTCM_FW_REG(fw_ver, V520, TOD_3);
                channel->sync_src = SYNC_SOURCE_DPLL3_TOD_PPS;
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static int idtcm_enable_channel(struct idtcm *idtcm, u32 index)
{
        struct idtcm_channel *channel;
        int err;
        int i;

        if (!(index < MAX_TOD))
                return -EINVAL;

        channel = &idtcm->channel[index];

        channel->idtcm = idtcm;
        channel->current_freq_scaled_ppm = 0;

        /* Set pll addresses */
        err = configure_channel_pll(channel);
        if (err)
                return err;

        /* Set tod addresses */
        err = configure_channel_tod(channel, index);
        if (err)
                return err;

        if (idtcm->fw_ver < V487)
                channel->caps = idtcm_caps_deprecated;
        else
                channel->caps = idtcm_caps;

        snprintf(channel->caps.name, sizeof(channel->caps.name),
                 "IDT CM TOD%u", index);

        channel->caps.pin_config = pin_config[index];

        for (i = 0; i < channel->caps.n_pins; ++i) {
                struct ptp_pin_desc *ppd = &channel->caps.pin_config[i];

                snprintf(ppd->name, sizeof(ppd->name), "input_ref%d", i);
                ppd->index = i;
                ppd->func = PTP_PF_NONE;
                ppd->chan = index;
        }

        err = initialize_dco_operating_mode(channel);
        if (err)
                return err;

        err = idtcm_enable_tod(channel);
        if (err) {
                dev_err(idtcm->dev,
                        "Failed at line %d in %s!", __LINE__, __func__);
                return err;
        }

        channel->dco_delay = idtcm_get_dco_delay(channel);

        channel->ptp_clock = ptp_clock_register(&channel->caps, NULL);

        if (IS_ERR(channel->ptp_clock)) {
                err = PTR_ERR(channel->ptp_clock);
                channel->ptp_clock = NULL;
                return err;
        }

        if (!channel->ptp_clock)
                return -ENOTSUPP;

        dev_info(idtcm->dev, "PLL%d registered as ptp%d",
                 index, channel->ptp_clock->index);

        return 0;
}

static int idtcm_enable_extts_channel(struct idtcm *idtcm, u32 index)
{
        struct idtcm_channel *channel;
        int err;

        if (!(index < MAX_TOD))
                return -EINVAL;

        channel = &idtcm->channel[index];
        channel->idtcm = idtcm;

        /* Set tod addresses */
        err = configure_channel_tod(channel, index);
        if (err)
                return err;

        channel->idtcm = idtcm;

        return 0;
}

static void idtcm_extts_check(struct work_struct *work)
{
        struct idtcm *idtcm = container_of(work, struct idtcm, extts_work.work);
        struct idtcm_channel *channel;
        u8 mask;
        int err;
        int i;

        if (idtcm->extts_mask == 0)
                return;

        mutex_lock(idtcm->lock);

        for (i = 0; i < MAX_TOD; i++) {
                mask = 1 << i;

                if ((idtcm->extts_mask & mask) == 0)
                        continue;

                err = idtcm_extts_check_channel(idtcm, i);

                if (err == 0) {
                        /* trigger clears itself, so clear the mask */
                        if (idtcm->extts_single_shot) {
                                idtcm->extts_mask &= ~mask;
                        } else {
                                /* Re-arm */
                                channel = &idtcm->channel[i];
                                arm_tod_read_trig_sel_refclk(channel, channel->refn);
                        }
                }
        }

        if (idtcm->extts_mask)
                schedule_delayed_work(&idtcm->extts_work,
                                      msecs_to_jiffies(EXTTS_PERIOD_MS));

        mutex_unlock(idtcm->lock);
}

static void ptp_clock_unregister_all(struct idtcm *idtcm)
{
        u8 i;
        struct idtcm_channel *channel;

        for (i = 0; i < MAX_TOD; i++) {
                channel = &idtcm->channel[i];
                if (channel->ptp_clock)
                        ptp_clock_unregister(channel->ptp_clock);
        }
}

static void set_default_masks(struct idtcm *idtcm)
{
        idtcm->tod_mask = DEFAULT_TOD_MASK;
        idtcm->extts_mask = 0;

        idtcm->channel[0].tod = 0;
        idtcm->channel[1].tod = 1;
        idtcm->channel[2].tod = 2;
        idtcm->channel[3].tod = 3;

        idtcm->channel[0].pll = DEFAULT_TOD0_PTP_PLL;
        idtcm->channel[1].pll = DEFAULT_TOD1_PTP_PLL;
        idtcm->channel[2].pll = DEFAULT_TOD2_PTP_PLL;
        idtcm->channel[3].pll = DEFAULT_TOD3_PTP_PLL;

        idtcm->channel[0].output_mask = DEFAULT_OUTPUT_MASK_PLL0;
        idtcm->channel[1].output_mask = DEFAULT_OUTPUT_MASK_PLL1;
        idtcm->channel[2].output_mask = DEFAULT_OUTPUT_MASK_PLL2;
        idtcm->channel[3].output_mask = DEFAULT_OUTPUT_MASK_PLL3;
}

static int idtcm_probe(struct platform_device *pdev)
{
        struct rsmu_ddata *ddata = dev_get_drvdata(pdev->dev.parent);
        struct idtcm *idtcm;
        int err;
        u8 i;

        idtcm = devm_kzalloc(&pdev->dev, sizeof(struct idtcm), GFP_KERNEL);

        if (!idtcm)
                return -ENOMEM;

        idtcm->dev = &pdev->dev;
        idtcm->mfd = pdev->dev.parent;
        idtcm->lock = &ddata->lock;
        idtcm->regmap = ddata->regmap;
        idtcm->calculate_overhead_flag = 0;

        INIT_DELAYED_WORK(&idtcm->extts_work, idtcm_extts_check);

        set_default_masks(idtcm);

        mutex_lock(idtcm->lock);

        idtcm_set_version_info(idtcm);

        err = idtcm_load_firmware(idtcm, &pdev->dev);

        if (err)
                dev_warn(idtcm->dev, "loading firmware failed with %d", err);

        wait_for_chip_ready(idtcm);

        if (idtcm->tod_mask) {
                for (i = 0; i < MAX_TOD; i++) {
                        if (idtcm->tod_mask & (1 << i))
                                err = idtcm_enable_channel(idtcm, i);
                        else
                                err = idtcm_enable_extts_channel(idtcm, i);
                        if (err) {
                                dev_err(idtcm->dev,
                                        "idtcm_enable_channel %d failed!", i);
                                break;
                        }
                }
        } else {
                dev_err(idtcm->dev,
                        "no PLLs flagged as PHCs, nothing to do");
                err = -ENODEV;
        }

        mutex_unlock(idtcm->lock);

        if (err) {
                ptp_clock_unregister_all(idtcm);
                return err;
        }

        platform_set_drvdata(pdev, idtcm);

        return 0;
}

static void idtcm_remove(struct platform_device *pdev)
{
        struct idtcm *idtcm = platform_get_drvdata(pdev);

        idtcm->extts_mask = 0;
        ptp_clock_unregister_all(idtcm);
        cancel_delayed_work_sync(&idtcm->extts_work);
}

static struct platform_driver idtcm_driver = {
        .driver = {
                .name = "8a3400x-phc",
        },
        .probe = idtcm_probe,
        .remove = idtcm_remove,
};

module_platform_driver(idtcm_driver);