On Mon, Mar 02, 2015 at 01:25:48PM +0800, Li Jun wrote:
> From: Li Jun <b47624@xxxxxxxxxxxxx>
>
> Current otg fsm timers are using controller 1ms irq and count it, this patch
> is to replace it with hrtimer solution, use one hrtimer for all otg timers.
>
> Signed-off-by: Li Jun <jun.li@xxxxxxxxxxxxx>
>
> Change for v3:
> - clean up the definitions for original timer solution: ci_otg_fsm_timer
> and ci_otg_fsm_timer_list in usb/chipidea/otg_fsm.h.
>
> Changes for v2:
> - change enabled_otg_timers to be enabled_otg_timer_bits.
> - Remove duplicated OTG 1MSIE disable in usb otg fsm init.
>
> ---
> drivers/usb/chipidea/ci.h | 10 +-
> drivers/usb/chipidea/otg_fsm.c | 364 ++++++++++++++++++++--------------------
> drivers/usb/chipidea/otg_fsm.h | 13 --
> 3 files changed, 190 insertions(+), 197 deletions(-)
>
> diff --git a/drivers/usb/chipidea/ci.h b/drivers/usb/chipidea/ci.h
> index c09381d..aeec5f0 100644
> --- a/drivers/usb/chipidea/ci.h
> +++ b/drivers/usb/chipidea/ci.h
> @@ -162,7 +162,10 @@ struct hw_bank {
> * @role: current role
> * @is_otg: if the device is otg-capable
> * @fsm: otg finite state machine
> - * @fsm_timer: pointer to timer list of otg fsm
> + * @otg_fsm_hrtimer: hrtimer for otg fsm timers
> + * @hr_timeouts: time out list for active otg fsm timers
> + * @enabled_otg_timer_bits: bits of enabled otg timers
> + * @next_otg_timer: next nearest enabled timer to be expired
> * @work: work for role changing
> * @wq: workqueue thread
> * @qh_pool: allocation pool for queue heads
> @@ -205,7 +208,10 @@ struct ci_hdrc {
> bool is_otg;
> struct usb_otg otg;
> struct otg_fsm fsm;
> - struct ci_otg_fsm_timer_list *fsm_timer;
> + struct hrtimer otg_fsm_hrtimer;
> + ktime_t hr_timeouts[NUM_OTG_FSM_TIMERS];
> + unsigned enabled_otg_timer_bits;
> + enum otg_fsm_timer next_otg_timer;
> struct work_struct work;
> struct workqueue_struct *wq;
>
> diff --git a/drivers/usb/chipidea/otg_fsm.c b/drivers/usb/chipidea/otg_fsm.c
> index ba2cb91..083acf4 100644
> --- a/drivers/usb/chipidea/otg_fsm.c
> +++ b/drivers/usb/chipidea/otg_fsm.c
> @@ -30,22 +30,6 @@
> #include "otg.h"
> #include "otg_fsm.h"
>
> -static struct ci_otg_fsm_timer *otg_timer_initializer
> -(struct ci_hdrc *ci, void (*function)(void *, unsigned long),
> - unsigned long expires, unsigned long data)
> -{
> - struct ci_otg_fsm_timer *timer;
> -
> - timer = devm_kzalloc(ci->dev, sizeof(struct ci_otg_fsm_timer),
> - GFP_KERNEL);
> - if (!timer)
> - return NULL;
> - timer->function = function;
> - timer->expires = expires;
> - timer->data = data;
> - return timer;
> -}
> -
> /* Add for otg: interact with user space app */
> static ssize_t
> get_a_bus_req(struct device *dev, struct device_attribute *attr, char *buf)
> @@ -204,36 +188,48 @@ static struct attribute_group inputs_attr_group = {
> };
>
> /*
> + * Keep this list in the same order as timers indexed
> + * by enum otg_fsm_timer in include/linux/usb/otg-fsm.h
> + */
> +static unsigned otg_timer_ms[] = {
> + TA_WAIT_VRISE,
> + TA_WAIT_VFALL,
> + TA_WAIT_BCON,
> + TA_AIDL_BDIS,
> + TB_ASE0_BRST,
> + TA_BIDL_ADIS,
> + TB_SE0_SRP,
> + TB_SRP_FAIL,
> + 0,
> + TB_DATA_PLS,
> + TB_SSEND_SRP,
> +};
> +
> +/*
> * Add timer to active timer list
> */
> static void ci_otg_add_timer(struct ci_hdrc *ci, enum otg_fsm_timer t)
> {
> - struct ci_otg_fsm_timer *tmp_timer;
> - struct ci_otg_fsm_timer *timer = ci->fsm_timer->timer_list[t];
> - struct list_head *active_timers = &ci->fsm_timer->active_timers;
> + unsigned long flags, timer_sec, timer_nsec;
>
> if (t >= NUM_OTG_FSM_TIMERS)
> return;
>
> - /*
> - * Check if the timer is already in the active list,
> - * if so update timer count
> - */
> - list_for_each_entry(tmp_timer, active_timers, list)
> - if (tmp_timer == timer) {
> - timer->count = timer->expires;
> - return;
> - }
> -
> - if (list_empty(active_timers))
> - pm_runtime_get(ci->dev);
> -
> - timer->count = timer->expires;
> - list_add_tail(&timer->list, active_timers);
> -
> - /* Enable 1ms irq */
> - if (!(hw_read_otgsc(ci, OTGSC_1MSIE)))
> - hw_write_otgsc(ci, OTGSC_1MSIE, OTGSC_1MSIE);
> + spin_lock_irqsave(&ci->lock, flags);
> + timer_sec = otg_timer_ms[t] / MSEC_PER_SEC;
> + timer_nsec = (otg_timer_ms[t] % MSEC_PER_SEC) * NSEC_PER_MSEC;
> + ci->hr_timeouts[t] = ktime_add(ktime_get(),
> + ktime_set(timer_sec, timer_nsec));
> + ci->enabled_otg_timer_bits |= (1 << t);
> + if ((ci->next_otg_timer == NUM_OTG_FSM_TIMERS) ||
> + (ci->hr_timeouts[ci->next_otg_timer].tv64 >
> + ci->hr_timeouts[t].tv64)) {
> + ci->next_otg_timer = t;
> + hrtimer_start_range_ns(&ci->otg_fsm_hrtimer,
> + ci->hr_timeouts[t], NSEC_PER_MSEC,
> + HRTIMER_MODE_ABS);
> + }
> + spin_unlock_irqrestore(&ci->lock, flags);
> }
>
> /*
> @@ -241,174 +237,178 @@ static void ci_otg_add_timer(struct ci_hdrc *ci, enum otg_fsm_timer t)
> */
> static void ci_otg_del_timer(struct ci_hdrc *ci, enum otg_fsm_timer t)
> {
> - struct ci_otg_fsm_timer *tmp_timer, *del_tmp;
> - struct ci_otg_fsm_timer *timer = ci->fsm_timer->timer_list[t];
> - struct list_head *active_timers = &ci->fsm_timer->active_timers;
> - int flag = 0;
> + unsigned long flags, enabled_timer_bits;
> + enum otg_fsm_timer cur_timer, next_timer = NUM_OTG_FSM_TIMERS;
>
> - if (t >= NUM_OTG_FSM_TIMERS)
> + if ((t >= NUM_OTG_FSM_TIMERS) ||
> + !(ci->enabled_otg_timer_bits & (1 << t)))
> return;
>
> - list_for_each_entry_safe(tmp_timer, del_tmp, active_timers, list)
> - if (tmp_timer == timer) {
> - list_del(&timer->list);
> - flag = 1;
> - }
> -
> - /* Disable 1ms irq if there is no any active timer */
> - if (list_empty(active_timers) && (flag == 1)) {
> - hw_write_otgsc(ci, OTGSC_1MSIE, 0);
> - pm_runtime_put(ci->dev);
> - }
> -}
> -
> -/*
> - * Reduce timer count by 1, and find timeout conditions.
> - * Called by otg 1ms timer interrupt
> - */
> -static inline int ci_otg_tick_timer(struct ci_hdrc *ci)
> -{
> - struct ci_otg_fsm_timer *tmp_timer, *del_tmp;
> - struct list_head *active_timers = &ci->fsm_timer->active_timers;
> - int expired = 0;
> -
> - list_for_each_entry_safe(tmp_timer, del_tmp, active_timers, list) {
> - tmp_timer->count--;
> - /* check if timer expires */
> - if (!tmp_timer->count) {
> - list_del(&tmp_timer->list);
> - tmp_timer->function(ci, tmp_timer->data);
> - expired = 1;
> + spin_lock_irqsave(&ci->lock, flags);
> + ci->enabled_otg_timer_bits &= ~(1 << t);
> + if (ci->next_otg_timer == t) {
> + if (ci->enabled_otg_timer_bits == 0) {
> + /* No enabled timers after delete it */
> + hrtimer_cancel(&ci->otg_fsm_hrtimer);
> + ci->next_otg_timer = NUM_OTG_FSM_TIMERS;
> + } else {
> + /* Find the next timer */
> + enabled_timer_bits = ci->enabled_otg_timer_bits;
> + for_each_set_bit(cur_timer, &enabled_timer_bits,
> + NUM_OTG_FSM_TIMERS) {
> + if ((next_timer == NUM_OTG_FSM_TIMERS) ||
> + (ci->hr_timeouts[next_timer].tv64 <
> + ci->hr_timeouts[cur_timer].tv64))
> + next_timer = cur_timer;
> + }
> }
> }
> -
> - /* disable 1ms irq if there is no any timer active */
> - if ((expired == 1) && list_empty(active_timers)) {
> - hw_write_otgsc(ci, OTGSC_1MSIE, 0);
> - pm_runtime_put(ci->dev);
> + if (next_timer != NUM_OTG_FSM_TIMERS) {
> + ci->next_otg_timer = next_timer;
> + hrtimer_start_range_ns(&ci->otg_fsm_hrtimer,
> + ci->hr_timeouts[next_timer], NSEC_PER_MSEC,
> + HRTIMER_MODE_ABS);
> }
> -
> - return expired;
> + spin_unlock_irqrestore(&ci->lock, flags);
> }
>
> -/* The timeout callback function to set time out bit */
> -static void set_tmout(void *ptr, unsigned long indicator)
> +/* OTG FSM timer handlers */
> +static int a_wait_vrise_tmout(struct ci_hdrc *ci)
> {
> - *(int *)indicator = 1;
> + ci->fsm.a_wait_vrise_tmout = 1;
> + return 0;
> }
>
> -static void set_tmout_and_fsm(void *ptr, unsigned long indicator)
> +static int a_wait_vfall_tmout(struct ci_hdrc *ci)
> {
> - struct ci_hdrc *ci = (struct ci_hdrc *)ptr;
> -
> - set_tmout(ci, indicator);
> -
> - ci_otg_queue_work(ci);
> + ci->fsm.a_wait_vfall_tmout = 1;
> + return 0;
> }
>
> -static void a_wait_vfall_tmout_func(void *ptr, unsigned long indicator)
> +static int a_wait_bcon_tmout(struct ci_hdrc *ci)
> {
> - struct ci_hdrc *ci = (struct ci_hdrc *)ptr;
> + ci->fsm.a_wait_bcon_tmout = 1;
> + return 0;
> +}
>
> - set_tmout(ci, indicator);
> - /* Disable port power */
> - hw_write(ci, OP_PORTSC, PORTSC_W1C_BITS | PORTSC_PP, 0);
> - /* Clear existing DP irq */
> - hw_write_otgsc(ci, OTGSC_DPIS, OTGSC_DPIS);
> - /* Enable data pulse irq */
> - hw_write_otgsc(ci, OTGSC_DPIE, OTGSC_DPIE);
> - ci_otg_queue_work(ci);
> +static int a_aidl_bdis_tmout(struct ci_hdrc *ci)
> +{
> + ci->fsm.a_aidl_bdis_tmout = 1;
> + return 0;
> }
>
> -static void b_ssend_srp_tmout_func(void *ptr, unsigned long indicator)
> +static int b_ase0_brst_tmout(struct ci_hdrc *ci)
> {
> - struct ci_hdrc *ci = (struct ci_hdrc *)ptr;
> + ci->fsm.b_ase0_brst_tmout = 1;
> + return 0;
> +}
>
> - set_tmout(ci, indicator);
> +static int a_bidl_adis_tmout(struct ci_hdrc *ci)
> +{
> + ci->fsm.a_bidl_adis_tmout = 1;
> + return 0;
> +}
>
> - /* only vbus fall below B_sess_vld in b_idle state */
> - if (ci->fsm.otg->state == OTG_STATE_B_IDLE)
> - ci_otg_queue_work(ci);
> +static int b_se0_srp_tmout(struct ci_hdrc *ci)
> +{
> + ci->fsm.b_se0_srp = 1;
> + return 0;
> }
>
> -static void b_data_pulse_end(void *ptr, unsigned long indicator)
> +static int b_srp_fail_tmout(struct ci_hdrc *ci)
> {
> - struct ci_hdrc *ci = (struct ci_hdrc *)ptr;
> + ci->fsm.b_srp_done = 1;
> + return 1;
> +}
>
> +static int b_data_pls_tmout(struct ci_hdrc *ci)
> +{
> ci->fsm.b_srp_done = 1;
> ci->fsm.b_bus_req = 0;
> if (ci->fsm.power_up)
> ci->fsm.power_up = 0;
> -
> hw_write_otgsc(ci, OTGSC_HABA, 0);
> + pm_runtime_put(ci->dev);
> + return 0;
> +}
>
> - ci_otg_queue_work(ci);
> +static int b_ssend_srp_tmout(struct ci_hdrc *ci)
> +{
> + ci->fsm.b_ssend_srp = 1;
> + /* only vbus fall below B_sess_vld in b_idle state */
> + if (ci->fsm.otg->state == OTG_STATE_B_IDLE)
> + return 0;
> + else
> + return 1;
> +}
> +
> +/*
> + * Keep this list in the same order as timers indexed
> + * by enum otg_fsm_timer in include/linux/usb/otg-fsm.h
> + */
> +static int (*otg_timer_handlers[])(struct ci_hdrc *) = {
> + a_wait_vrise_tmout, /* A_WAIT_VRISE */
> + a_wait_vfall_tmout, /* A_WAIT_VFALL */
> + a_wait_bcon_tmout, /* A_WAIT_BCON */
> + a_aidl_bdis_tmout, /* A_AIDL_BDIS */
> + b_ase0_brst_tmout, /* B_ASE0_BRST */
> + a_bidl_adis_tmout, /* A_BIDL_ADIS */
> + b_se0_srp_tmout, /* B_SE0_SRP */
> + b_srp_fail_tmout, /* B_SRP_FAIL */
> + NULL, /* A_WAIT_ENUM */
> + b_data_pls_tmout, /* B_DATA_PLS */
> + b_ssend_srp_tmout, /* B_SSEND_SRP */
> +};
> +
> +/*
> + * Enable the next nearest enabled timer if have
> + */
> +static enum hrtimer_restart ci_otg_hrtimer_func(struct hrtimer *t)
> +{
> + struct ci_hdrc *ci = container_of(t, struct ci_hdrc, otg_fsm_hrtimer);
> + ktime_t now, *timeout;
> + unsigned long enabled_timer_bits;
> + unsigned long flags;
> + enum otg_fsm_timer cur_timer, next_timer = NUM_OTG_FSM_TIMERS;
> + int ret = -EINVAL;
> +
> + spin_lock_irqsave(&ci->lock, flags);
> + enabled_timer_bits = ci->enabled_otg_timer_bits;
> + ci->next_otg_timer = NUM_OTG_FSM_TIMERS;
> +
> + now = ktime_get();
> + for_each_set_bit(cur_timer, &enabled_timer_bits, NUM_OTG_FSM_TIMERS) {
> + if (now.tv64 >= ci->hr_timeouts[cur_timer].tv64) {
> + ci->enabled_otg_timer_bits &= ~(1 << cur_timer);
> + if (otg_timer_handlers[cur_timer])
> + ret = otg_timer_handlers[cur_timer](ci);
> + } else {
> + if ((next_timer == NUM_OTG_FSM_TIMERS) ||
> + (ci->hr_timeouts[cur_timer].tv64 <
> + ci->hr_timeouts[next_timer].tv64))
> + next_timer = cur_timer;
> + }
> + }
> + /* Enable the next nearest timer */
> + if (next_timer < NUM_OTG_FSM_TIMERS) {
> + timeout = &ci->hr_timeouts[next_timer];
> + hrtimer_start_range_ns(&ci->otg_fsm_hrtimer, *timeout,
> + NSEC_PER_MSEC, HRTIMER_MODE_ABS);
> + ci->next_otg_timer = next_timer;
> + }
> + spin_unlock_irqrestore(&ci->lock, flags);
> +
> + if (!ret)
> + ci_otg_queue_work(ci);
> +
> + return HRTIMER_NORESTART;
> }
>
> /* Initialize timers */
> static int ci_otg_init_timers(struct ci_hdrc *ci)
> {
> - struct otg_fsm *fsm = &ci->fsm;
> -
> - /* FSM used timers */
> - ci->fsm_timer->timer_list[A_WAIT_VRISE] =
> - otg_timer_initializer(ci, &set_tmout_and_fsm, TA_WAIT_VRISE,
> - (unsigned long)&fsm->a_wait_vrise_tmout);
> - if (ci->fsm_timer->timer_list[A_WAIT_VRISE] == NULL)
> - return -ENOMEM;
> -
> - ci->fsm_timer->timer_list[A_WAIT_VFALL] =
> - otg_timer_initializer(ci, &a_wait_vfall_tmout_func,
> - TA_WAIT_VFALL, (unsigned long)&fsm->a_wait_vfall_tmout);
> - if (ci->fsm_timer->timer_list[A_WAIT_VFALL] == NULL)
> - return -ENOMEM;
> -
> - ci->fsm_timer->timer_list[A_WAIT_BCON] =
> - otg_timer_initializer(ci, &set_tmout_and_fsm, TA_WAIT_BCON,
> - (unsigned long)&fsm->a_wait_bcon_tmout);
> - if (ci->fsm_timer->timer_list[A_WAIT_BCON] == NULL)
> - return -ENOMEM;
> -
> - ci->fsm_timer->timer_list[A_AIDL_BDIS] =
> - otg_timer_initializer(ci, &set_tmout_and_fsm, TA_AIDL_BDIS,
> - (unsigned long)&fsm->a_aidl_bdis_tmout);
> - if (ci->fsm_timer->timer_list[A_AIDL_BDIS] == NULL)
> - return -ENOMEM;
> -
> - ci->fsm_timer->timer_list[A_BIDL_ADIS] =
> - otg_timer_initializer(ci, &set_tmout_and_fsm, TA_BIDL_ADIS,
> - (unsigned long)&fsm->a_bidl_adis_tmout);
> - if (ci->fsm_timer->timer_list[A_BIDL_ADIS] == NULL)
> - return -ENOMEM;
> -
> - ci->fsm_timer->timer_list[B_ASE0_BRST] =
> - otg_timer_initializer(ci, &set_tmout_and_fsm, TB_ASE0_BRST,
> - (unsigned long)&fsm->b_ase0_brst_tmout);
> - if (ci->fsm_timer->timer_list[B_ASE0_BRST] == NULL)
> - return -ENOMEM;
> -
> - ci->fsm_timer->timer_list[B_SE0_SRP] =
> - otg_timer_initializer(ci, &set_tmout_and_fsm, TB_SE0_SRP,
> - (unsigned long)&fsm->b_se0_srp);
> - if (ci->fsm_timer->timer_list[B_SE0_SRP] == NULL)
> - return -ENOMEM;
> -
> - ci->fsm_timer->timer_list[B_SSEND_SRP] =
> - otg_timer_initializer(ci, &b_ssend_srp_tmout_func, TB_SSEND_SRP,
> - (unsigned long)&fsm->b_ssend_srp);
> - if (ci->fsm_timer->timer_list[B_SSEND_SRP] == NULL)
> - return -ENOMEM;
> -
> - ci->fsm_timer->timer_list[B_SRP_FAIL] =
> - otg_timer_initializer(ci, &set_tmout, TB_SRP_FAIL,
> - (unsigned long)&fsm->b_srp_done);
> - if (ci->fsm_timer->timer_list[B_SRP_FAIL] == NULL)
> - return -ENOMEM;
> -
> - ci->fsm_timer->timer_list[B_DATA_PLS] =
> - otg_timer_initializer(ci, &b_data_pulse_end, TB_DATA_PLS, 0);
> - if (ci->fsm_timer->timer_list[B_DATA_PLS] == NULL)
> - return -ENOMEM;
> + hrtimer_init(&ci->otg_fsm_hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
> + ci->otg_fsm_hrtimer.function = ci_otg_hrtimer_func;
>
> return 0;
> }
> @@ -512,6 +512,7 @@ static void ci_otg_start_pulse(struct otg_fsm *fsm)
> /* Hardware Assistant Data pulse */
> hw_write_otgsc(ci, OTGSC_HADP, OTGSC_HADP);
>
> + pm_runtime_get(ci->dev);
> ci_otg_add_timer(ci, B_DATA_PLS);
> }
>
> @@ -579,8 +580,15 @@ int ci_otg_fsm_work(struct ci_hdrc *ci)
> * a_idle to a_wait_vrise when power up
> */
> if ((ci->fsm.id) || (ci->id_event) ||
> - (ci->fsm.power_up))
> + (ci->fsm.power_up)) {
> ci_otg_queue_work(ci);
> + } else {
> + /* Enable data pulse irq */
> + hw_write(ci, OP_PORTSC, PORTSC_W1C_BITS |
> + PORTSC_PP, 0);
> + hw_write_otgsc(ci, OTGSC_DPIS, OTGSC_DPIS);
> + hw_write_otgsc(ci, OTGSC_DPIE, OTGSC_DPIE);
> + }
> if (ci->id_event)
> ci->id_event = false;
> } else if (ci->fsm.otg->state == OTG_STATE_B_IDLE) {
> @@ -712,11 +720,7 @@ irqreturn_t ci_otg_fsm_irq(struct ci_hdrc *ci)
> fsm->id = (otgsc & OTGSC_ID) ? 1 : 0;
>
> if (otg_int_src) {
> - if (otg_int_src & OTGSC_1MSIS) {
> - hw_write_otgsc(ci, OTGSC_1MSIS, OTGSC_1MSIS);
> - retval = ci_otg_tick_timer(ci);
> - return IRQ_HANDLED;
> - } else if (otg_int_src & OTGSC_DPIS) {
> + if (otg_int_src & OTGSC_DPIS) {
> hw_write_otgsc(ci, OTGSC_DPIS, OTGSC_DPIS);
> fsm->a_srp_det = 1;
> fsm->a_bus_drop = 0;
> @@ -780,17 +784,13 @@ int ci_hdrc_otg_fsm_init(struct ci_hdrc *ci)
>
> mutex_init(&ci->fsm.lock);
>
> - ci->fsm_timer = devm_kzalloc(ci->dev,
> - sizeof(struct ci_otg_fsm_timer_list), GFP_KERNEL);
> - if (!ci->fsm_timer)
> - return -ENOMEM;
> -
> - INIT_LIST_HEAD(&ci->fsm_timer->active_timers);
> retval = ci_otg_init_timers(ci);
> if (retval) {
> dev_err(ci->dev, "Couldn't init OTG timers\n");
> return retval;
> }
> + ci->enabled_otg_timer_bits = 0;
> + ci->next_otg_timer = NUM_OTG_FSM_TIMERS;
>
> retval = sysfs_create_group(&ci->dev->kobj, &inputs_attr_group);
> if (retval < 0) {
> diff --git a/drivers/usb/chipidea/otg_fsm.h b/drivers/usb/chipidea/otg_fsm.h
> index 9e0fc4c..2689375 100644
> --- a/drivers/usb/chipidea/otg_fsm.h
> +++ b/drivers/usb/chipidea/otg_fsm.h
> @@ -62,19 +62,6 @@
> /* SSEND time before SRP */
> #define TB_SSEND_SRP (1500) /* minimum 1.5 sec, section:5.1.2 */
>
> -struct ci_otg_fsm_timer {
> - unsigned long expires; /* Number of count increase to timeout */
> - unsigned long count; /* Tick counter */
> - void (*function)(void *, unsigned long); /* Timeout function */
> - unsigned long data; /* Data passed to function */
> - struct list_head list;
> -};
> -
> -struct ci_otg_fsm_timer_list {
> - struct ci_otg_fsm_timer *timer_list[NUM_OTG_FSM_TIMERS];
> - struct list_head active_timers;
> -};
> -
> #ifdef CONFIG_USB_OTG_FSM
>
> int ci_hdrc_otg_fsm_init(struct ci_hdrc *ci);
> --
> 1.7.9.5
>
All three patches have applied, thanks.
--
Best Regards,
Peter Chen
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