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-rw-r--r--drivers/usb/dwc2/hcd_queue.c2069
1 files changed, 2069 insertions, 0 deletions
diff --git a/drivers/usb/dwc2/hcd_queue.c b/drivers/usb/dwc2/hcd_queue.c
new file mode 100644
index 000000000..0a1145592
--- /dev/null
+++ b/drivers/usb/dwc2/hcd_queue.c
@@ -0,0 +1,2069 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
+/*
+ * hcd_queue.c - DesignWare HS OTG Controller host queuing routines
+ *
+ * Copyright (C) 2004-2013 Synopsys, Inc.
+ */
+
+/*
+ * This file contains the functions to manage Queue Heads and Queue
+ * Transfer Descriptors for Host mode
+ */
+#include <linux/gcd.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/dma-mapping.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+
+#include <linux/usb/hcd.h>
+#include <linux/usb/ch11.h>
+
+#include "core.h"
+#include "hcd.h"
+
+/* Wait this long before releasing periodic reservation */
+#define DWC2_UNRESERVE_DELAY (msecs_to_jiffies(5))
+
+/* If we get a NAK, wait this long before retrying */
+#define DWC2_RETRY_WAIT_DELAY (1 * NSEC_PER_MSEC)
+
+/**
+ * dwc2_periodic_channel_available() - Checks that a channel is available for a
+ * periodic transfer
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller
+ *
+ * Return: 0 if successful, negative error code otherwise
+ */
+static int dwc2_periodic_channel_available(struct dwc2_hsotg *hsotg)
+{
+ /*
+ * Currently assuming that there is a dedicated host channel for
+ * each periodic transaction plus at least one host channel for
+ * non-periodic transactions
+ */
+ int status;
+ int num_channels;
+
+ num_channels = hsotg->params.host_channels;
+ if ((hsotg->periodic_channels + hsotg->non_periodic_channels <
+ num_channels) && (hsotg->periodic_channels < num_channels - 1)) {
+ status = 0;
+ } else {
+ dev_dbg(hsotg->dev,
+ "%s: Total channels: %d, Periodic: %d, Non-periodic: %d\n",
+ __func__, num_channels,
+ hsotg->periodic_channels, hsotg->non_periodic_channels);
+ status = -ENOSPC;
+ }
+
+ return status;
+}
+
+/**
+ * dwc2_check_periodic_bandwidth() - Checks that there is sufficient bandwidth
+ * for the specified QH in the periodic schedule
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller
+ * @qh: QH containing periodic bandwidth required
+ *
+ * Return: 0 if successful, negative error code otherwise
+ *
+ * For simplicity, this calculation assumes that all the transfers in the
+ * periodic schedule may occur in the same (micro)frame
+ */
+static int dwc2_check_periodic_bandwidth(struct dwc2_hsotg *hsotg,
+ struct dwc2_qh *qh)
+{
+ int status;
+ s16 max_claimed_usecs;
+
+ status = 0;
+
+ if (qh->dev_speed == USB_SPEED_HIGH || qh->do_split) {
+ /*
+ * High speed mode
+ * Max periodic usecs is 80% x 125 usec = 100 usec
+ */
+ max_claimed_usecs = 100 - qh->host_us;
+ } else {
+ /*
+ * Full speed mode
+ * Max periodic usecs is 90% x 1000 usec = 900 usec
+ */
+ max_claimed_usecs = 900 - qh->host_us;
+ }
+
+ if (hsotg->periodic_usecs > max_claimed_usecs) {
+ dev_err(hsotg->dev,
+ "%s: already claimed usecs %d, required usecs %d\n",
+ __func__, hsotg->periodic_usecs, qh->host_us);
+ status = -ENOSPC;
+ }
+
+ return status;
+}
+
+/**
+ * pmap_schedule() - Schedule time in a periodic bitmap (pmap).
+ *
+ * @map: The bitmap representing the schedule; will be updated
+ * upon success.
+ * @bits_per_period: The schedule represents several periods. This is how many
+ * bits are in each period. It's assumed that the beginning
+ * of the schedule will repeat after its end.
+ * @periods_in_map: The number of periods in the schedule.
+ * @num_bits: The number of bits we need per period we want to reserve
+ * in this function call.
+ * @interval: How often we need to be scheduled for the reservation this
+ * time. 1 means every period. 2 means every other period.
+ * ...you get the picture?
+ * @start: The bit number to start at. Normally 0. Must be within
+ * the interval or we return failure right away.
+ * @only_one_period: Normally we'll allow picking a start anywhere within the
+ * first interval, since we can still make all repetition
+ * requirements by doing that. However, if you pass true
+ * here then we'll return failure if we can't fit within
+ * the period that "start" is in.
+ *
+ * The idea here is that we want to schedule time for repeating events that all
+ * want the same resource. The resource is divided into fixed-sized periods
+ * and the events want to repeat every "interval" periods. The schedule
+ * granularity is one bit.
+ *
+ * To keep things "simple", we'll represent our schedule with a bitmap that
+ * contains a fixed number of periods. This gets rid of a lot of complexity
+ * but does mean that we need to handle things specially (and non-ideally) if
+ * the number of the periods in the schedule doesn't match well with the
+ * intervals that we're trying to schedule.
+ *
+ * Here's an explanation of the scheme we'll implement, assuming 8 periods.
+ * - If interval is 1, we need to take up space in each of the 8
+ * periods we're scheduling. Easy.
+ * - If interval is 2, we need to take up space in half of the
+ * periods. Again, easy.
+ * - If interval is 3, we actually need to fall back to interval 1.
+ * Why? Because we might need time in any period. AKA for the
+ * first 8 periods, we'll be in slot 0, 3, 6. Then we'll be
+ * in slot 1, 4, 7. Then we'll be in 2, 5. Then we'll be back to
+ * 0, 3, and 6. Since we could be in any frame we need to reserve
+ * for all of them. Sucks, but that's what you gotta do. Note that
+ * if we were instead scheduling 8 * 3 = 24 we'd do much better, but
+ * then we need more memory and time to do scheduling.
+ * - If interval is 4, easy.
+ * - If interval is 5, we again need interval 1. The schedule will be
+ * 0, 5, 2, 7, 4, 1, 6, 3, 0
+ * - If interval is 6, we need interval 2. 0, 6, 4, 2.
+ * - If interval is 7, we need interval 1.
+ * - If interval is 8, we need interval 8.
+ *
+ * If you do the math, you'll see that we need to pretend that interval is
+ * equal to the greatest_common_divisor(interval, periods_in_map).
+ *
+ * Note that at the moment this function tends to front-pack the schedule.
+ * In some cases that's really non-ideal (it's hard to schedule things that
+ * need to repeat every period). In other cases it's perfect (you can easily
+ * schedule bigger, less often repeating things).
+ *
+ * Here's the algorithm in action (8 periods, 5 bits per period):
+ * |** | |** | |** | |** | | OK 2 bits, intv 2 at 0
+ * |*****| ***|*****| ***|*****| ***|*****| ***| OK 3 bits, intv 3 at 2
+ * |*****|* ***|*****| ***|*****|* ***|*****| ***| OK 1 bits, intv 4 at 5
+ * |** |* |** | |** |* |** | | Remv 3 bits, intv 3 at 2
+ * |*** |* |*** | |*** |* |*** | | OK 1 bits, intv 6 at 2
+ * |**** |* * |**** | * |**** |* * |**** | * | OK 1 bits, intv 1 at 3
+ * |**** |**** |**** | *** |**** |**** |**** | *** | OK 2 bits, intv 2 at 6
+ * |*****|*****|*****| ****|*****|*****|*****| ****| OK 1 bits, intv 1 at 4
+ * |*****|*****|*****| ****|*****|*****|*****| ****| FAIL 1 bits, intv 1
+ * | ***|*****| ***| ****| ***|*****| ***| ****| Remv 2 bits, intv 2 at 0
+ * | ***| ****| ***| ****| ***| ****| ***| ****| Remv 1 bits, intv 4 at 5
+ * | **| ****| **| ****| **| ****| **| ****| Remv 1 bits, intv 6 at 2
+ * | *| ** *| *| ** *| *| ** *| *| ** *| Remv 1 bits, intv 1 at 3
+ * | *| *| *| *| *| *| *| *| Remv 2 bits, intv 2 at 6
+ * | | | | | | | | | Remv 1 bits, intv 1 at 4
+ * |** | |** | |** | |** | | OK 2 bits, intv 2 at 0
+ * |*** | |** | |*** | |** | | OK 1 bits, intv 4 at 2
+ * |*****| |** **| |*****| |** **| | OK 2 bits, intv 2 at 3
+ * |*****|* |** **| |*****|* |** **| | OK 1 bits, intv 4 at 5
+ * |*****|*** |** **| ** |*****|*** |** **| ** | OK 2 bits, intv 2 at 6
+ * |*****|*****|** **| ****|*****|*****|** **| ****| OK 2 bits, intv 2 at 8
+ * |*****|*****|*****| ****|*****|*****|*****| ****| OK 1 bits, intv 4 at 12
+ *
+ * This function is pretty generic and could be easily abstracted if anything
+ * needed similar scheduling.
+ *
+ * Returns either -ENOSPC or a >= 0 start bit which should be passed to the
+ * unschedule routine. The map bitmap will be updated on a non-error result.
+ */
+static int pmap_schedule(unsigned long *map, int bits_per_period,
+ int periods_in_map, int num_bits,
+ int interval, int start, bool only_one_period)
+{
+ int interval_bits;
+ int to_reserve;
+ int first_end;
+ int i;
+
+ if (num_bits > bits_per_period)
+ return -ENOSPC;
+
+ /* Adjust interval as per description */
+ interval = gcd(interval, periods_in_map);
+
+ interval_bits = bits_per_period * interval;
+ to_reserve = periods_in_map / interval;
+
+ /* If start has gotten us past interval then we can't schedule */
+ if (start >= interval_bits)
+ return -ENOSPC;
+
+ if (only_one_period)
+ /* Must fit within same period as start; end at begin of next */
+ first_end = (start / bits_per_period + 1) * bits_per_period;
+ else
+ /* Can fit anywhere in the first interval */
+ first_end = interval_bits;
+
+ /*
+ * We'll try to pick the first repetition, then see if that time
+ * is free for each of the subsequent repetitions. If it's not
+ * we'll adjust the start time for the next search of the first
+ * repetition.
+ */
+ while (start + num_bits <= first_end) {
+ int end;
+
+ /* Need to stay within this period */
+ end = (start / bits_per_period + 1) * bits_per_period;
+
+ /* Look for num_bits us in this microframe starting at start */
+ start = bitmap_find_next_zero_area(map, end, start, num_bits,
+ 0);
+
+ /*
+ * We should get start >= end if we fail. We might be
+ * able to check the next microframe depending on the
+ * interval, so continue on (start already updated).
+ */
+ if (start >= end) {
+ start = end;
+ continue;
+ }
+
+ /* At this point we have a valid point for first one */
+ for (i = 1; i < to_reserve; i++) {
+ int ith_start = start + interval_bits * i;
+ int ith_end = end + interval_bits * i;
+ int ret;
+
+ /* Use this as a dumb "check if bits are 0" */
+ ret = bitmap_find_next_zero_area(
+ map, ith_start + num_bits, ith_start, num_bits,
+ 0);
+
+ /* We got the right place, continue checking */
+ if (ret == ith_start)
+ continue;
+
+ /* Move start up for next time and exit for loop */
+ ith_start = bitmap_find_next_zero_area(
+ map, ith_end, ith_start, num_bits, 0);
+ if (ith_start >= ith_end)
+ /* Need a while new period next time */
+ start = end;
+ else
+ start = ith_start - interval_bits * i;
+ break;
+ }
+
+ /* If didn't exit the for loop with a break, we have success */
+ if (i == to_reserve)
+ break;
+ }
+
+ if (start + num_bits > first_end)
+ return -ENOSPC;
+
+ for (i = 0; i < to_reserve; i++) {
+ int ith_start = start + interval_bits * i;
+
+ bitmap_set(map, ith_start, num_bits);
+ }
+
+ return start;
+}
+
+/**
+ * pmap_unschedule() - Undo work done by pmap_schedule()
+ *
+ * @map: See pmap_schedule().
+ * @bits_per_period: See pmap_schedule().
+ * @periods_in_map: See pmap_schedule().
+ * @num_bits: The number of bits that was passed to schedule.
+ * @interval: The interval that was passed to schedule.
+ * @start: The return value from pmap_schedule().
+ */
+static void pmap_unschedule(unsigned long *map, int bits_per_period,
+ int periods_in_map, int num_bits,
+ int interval, int start)
+{
+ int interval_bits;
+ int to_release;
+ int i;
+
+ /* Adjust interval as per description in pmap_schedule() */
+ interval = gcd(interval, periods_in_map);
+
+ interval_bits = bits_per_period * interval;
+ to_release = periods_in_map / interval;
+
+ for (i = 0; i < to_release; i++) {
+ int ith_start = start + interval_bits * i;
+
+ bitmap_clear(map, ith_start, num_bits);
+ }
+}
+
+/**
+ * dwc2_get_ls_map() - Get the map used for the given qh
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller.
+ * @qh: QH for the periodic transfer.
+ *
+ * We'll always get the periodic map out of our TT. Note that even if we're
+ * running the host straight in low speed / full speed mode it appears as if
+ * a TT is allocated for us, so we'll use it. If that ever changes we can
+ * add logic here to get a map out of "hsotg" if !qh->do_split.
+ *
+ * Returns: the map or NULL if a map couldn't be found.
+ */
+static unsigned long *dwc2_get_ls_map(struct dwc2_hsotg *hsotg,
+ struct dwc2_qh *qh)
+{
+ unsigned long *map;
+
+ /* Don't expect to be missing a TT and be doing low speed scheduling */
+ if (WARN_ON(!qh->dwc_tt))
+ return NULL;
+
+ /* Get the map and adjust if this is a multi_tt hub */
+ map = qh->dwc_tt->periodic_bitmaps;
+ if (qh->dwc_tt->usb_tt->multi)
+ map += DWC2_ELEMENTS_PER_LS_BITMAP * (qh->ttport - 1);
+
+ return map;
+}
+
+#ifdef DWC2_PRINT_SCHEDULE
+/*
+ * cat_printf() - A printf() + strcat() helper
+ *
+ * This is useful for concatenating a bunch of strings where each string is
+ * constructed using printf.
+ *
+ * @buf: The destination buffer; will be updated to point after the printed
+ * data.
+ * @size: The number of bytes in the buffer (includes space for '\0').
+ * @fmt: The format for printf.
+ * @...: The args for printf.
+ */
+static __printf(3, 4)
+void cat_printf(char **buf, size_t *size, const char *fmt, ...)
+{
+ va_list args;
+ int i;
+
+ if (*size == 0)
+ return;
+
+ va_start(args, fmt);
+ i = vsnprintf(*buf, *size, fmt, args);
+ va_end(args);
+
+ if (i >= *size) {
+ (*buf)[*size - 1] = '\0';
+ *buf += *size;
+ *size = 0;
+ } else {
+ *buf += i;
+ *size -= i;
+ }
+}
+
+/*
+ * pmap_print() - Print the given periodic map
+ *
+ * Will attempt to print out the periodic schedule.
+ *
+ * @map: See pmap_schedule().
+ * @bits_per_period: See pmap_schedule().
+ * @periods_in_map: See pmap_schedule().
+ * @period_name: The name of 1 period, like "uFrame"
+ * @units: The name of the units, like "us".
+ * @print_fn: The function to call for printing.
+ * @print_data: Opaque data to pass to the print function.
+ */
+static void pmap_print(unsigned long *map, int bits_per_period,
+ int periods_in_map, const char *period_name,
+ const char *units,
+ void (*print_fn)(const char *str, void *data),
+ void *print_data)
+{
+ int period;
+
+ for (period = 0; period < periods_in_map; period++) {
+ char tmp[64];
+ char *buf = tmp;
+ size_t buf_size = sizeof(tmp);
+ int period_start = period * bits_per_period;
+ int period_end = period_start + bits_per_period;
+ int start = 0;
+ int count = 0;
+ bool printed = false;
+ int i;
+
+ for (i = period_start; i < period_end + 1; i++) {
+ /* Handle case when ith bit is set */
+ if (i < period_end &&
+ bitmap_find_next_zero_area(map, i + 1,
+ i, 1, 0) != i) {
+ if (count == 0)
+ start = i - period_start;
+ count++;
+ continue;
+ }
+
+ /* ith bit isn't set; don't care if count == 0 */
+ if (count == 0)
+ continue;
+
+ if (!printed)
+ cat_printf(&buf, &buf_size, "%s %d: ",
+ period_name, period);
+ else
+ cat_printf(&buf, &buf_size, ", ");
+ printed = true;
+
+ cat_printf(&buf, &buf_size, "%d %s -%3d %s", start,
+ units, start + count - 1, units);
+ count = 0;
+ }
+
+ if (printed)
+ print_fn(tmp, print_data);
+ }
+}
+
+struct dwc2_qh_print_data {
+ struct dwc2_hsotg *hsotg;
+ struct dwc2_qh *qh;
+};
+
+/**
+ * dwc2_qh_print() - Helper function for dwc2_qh_schedule_print()
+ *
+ * @str: The string to print
+ * @data: A pointer to a struct dwc2_qh_print_data
+ */
+static void dwc2_qh_print(const char *str, void *data)
+{
+ struct dwc2_qh_print_data *print_data = data;
+
+ dwc2_sch_dbg(print_data->hsotg, "QH=%p ...%s\n", print_data->qh, str);
+}
+
+/**
+ * dwc2_qh_schedule_print() - Print the periodic schedule
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller.
+ * @qh: QH to print.
+ */
+static void dwc2_qh_schedule_print(struct dwc2_hsotg *hsotg,
+ struct dwc2_qh *qh)
+{
+ struct dwc2_qh_print_data print_data = { hsotg, qh };
+ int i;
+
+ /*
+ * The printing functions are quite slow and inefficient.
+ * If we don't have tracing turned on, don't run unless the special
+ * define is turned on.
+ */
+
+ if (qh->schedule_low_speed) {
+ unsigned long *map = dwc2_get_ls_map(hsotg, qh);
+
+ dwc2_sch_dbg(hsotg, "QH=%p LS/FS trans: %d=>%d us @ %d us",
+ qh, qh->device_us,
+ DWC2_ROUND_US_TO_SLICE(qh->device_us),
+ DWC2_US_PER_SLICE * qh->ls_start_schedule_slice);
+
+ if (map) {
+ dwc2_sch_dbg(hsotg,
+ "QH=%p Whole low/full speed map %p now:\n",
+ qh, map);
+ pmap_print(map, DWC2_LS_PERIODIC_SLICES_PER_FRAME,
+ DWC2_LS_SCHEDULE_FRAMES, "Frame ", "slices",
+ dwc2_qh_print, &print_data);
+ }
+ }
+
+ for (i = 0; i < qh->num_hs_transfers; i++) {
+ struct dwc2_hs_transfer_time *trans_time = qh->hs_transfers + i;
+ int uframe = trans_time->start_schedule_us /
+ DWC2_HS_PERIODIC_US_PER_UFRAME;
+ int rel_us = trans_time->start_schedule_us %
+ DWC2_HS_PERIODIC_US_PER_UFRAME;
+
+ dwc2_sch_dbg(hsotg,
+ "QH=%p HS trans #%d: %d us @ uFrame %d + %d us\n",
+ qh, i, trans_time->duration_us, uframe, rel_us);
+ }
+ if (qh->num_hs_transfers) {
+ dwc2_sch_dbg(hsotg, "QH=%p Whole high speed map now:\n", qh);
+ pmap_print(hsotg->hs_periodic_bitmap,
+ DWC2_HS_PERIODIC_US_PER_UFRAME,
+ DWC2_HS_SCHEDULE_UFRAMES, "uFrame", "us",
+ dwc2_qh_print, &print_data);
+ }
+}
+#else
+static inline void dwc2_qh_schedule_print(struct dwc2_hsotg *hsotg,
+ struct dwc2_qh *qh) {};
+#endif
+
+/**
+ * dwc2_ls_pmap_schedule() - Schedule a low speed QH
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller.
+ * @qh: QH for the periodic transfer.
+ * @search_slice: We'll start trying to schedule at the passed slice.
+ * Remember that slices are the units of the low speed
+ * schedule (think 25us or so).
+ *
+ * Wraps pmap_schedule() with the right parameters for low speed scheduling.
+ *
+ * Normally we schedule low speed devices on the map associated with the TT.
+ *
+ * Returns: 0 for success or an error code.
+ */
+static int dwc2_ls_pmap_schedule(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
+ int search_slice)
+{
+ int slices = DIV_ROUND_UP(qh->device_us, DWC2_US_PER_SLICE);
+ unsigned long *map = dwc2_get_ls_map(hsotg, qh);
+ int slice;
+
+ if (!map)
+ return -EINVAL;
+
+ /*
+ * Schedule on the proper low speed map with our low speed scheduling
+ * parameters. Note that we use the "device_interval" here since
+ * we want the low speed interval and the only way we'd be in this
+ * function is if the device is low speed.
+ *
+ * If we happen to be doing low speed and high speed scheduling for the
+ * same transaction (AKA we have a split) we always do low speed first.
+ * That means we can always pass "false" for only_one_period (that
+ * parameters is only useful when we're trying to get one schedule to
+ * match what we already planned in the other schedule).
+ */
+ slice = pmap_schedule(map, DWC2_LS_PERIODIC_SLICES_PER_FRAME,
+ DWC2_LS_SCHEDULE_FRAMES, slices,
+ qh->device_interval, search_slice, false);
+
+ if (slice < 0)
+ return slice;
+
+ qh->ls_start_schedule_slice = slice;
+ return 0;
+}
+
+/**
+ * dwc2_ls_pmap_unschedule() - Undo work done by dwc2_ls_pmap_schedule()
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller.
+ * @qh: QH for the periodic transfer.
+ */
+static void dwc2_ls_pmap_unschedule(struct dwc2_hsotg *hsotg,
+ struct dwc2_qh *qh)
+{
+ int slices = DIV_ROUND_UP(qh->device_us, DWC2_US_PER_SLICE);
+ unsigned long *map = dwc2_get_ls_map(hsotg, qh);
+
+ /* Schedule should have failed, so no worries about no error code */
+ if (!map)
+ return;
+
+ pmap_unschedule(map, DWC2_LS_PERIODIC_SLICES_PER_FRAME,
+ DWC2_LS_SCHEDULE_FRAMES, slices, qh->device_interval,
+ qh->ls_start_schedule_slice);
+}
+
+/**
+ * dwc2_hs_pmap_schedule - Schedule in the main high speed schedule
+ *
+ * This will schedule something on the main dwc2 schedule.
+ *
+ * We'll start looking in qh->hs_transfers[index].start_schedule_us. We'll
+ * update this with the result upon success. We also use the duration from
+ * the same structure.
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller.
+ * @qh: QH for the periodic transfer.
+ * @only_one_period: If true we will limit ourselves to just looking at
+ * one period (aka one 100us chunk). This is used if we have
+ * already scheduled something on the low speed schedule and
+ * need to find something that matches on the high speed one.
+ * @index: The index into qh->hs_transfers that we're working with.
+ *
+ * Returns: 0 for success or an error code. Upon success the
+ * dwc2_hs_transfer_time specified by "index" will be updated.
+ */
+static int dwc2_hs_pmap_schedule(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
+ bool only_one_period, int index)
+{
+ struct dwc2_hs_transfer_time *trans_time = qh->hs_transfers + index;
+ int us;
+
+ us = pmap_schedule(hsotg->hs_periodic_bitmap,
+ DWC2_HS_PERIODIC_US_PER_UFRAME,
+ DWC2_HS_SCHEDULE_UFRAMES, trans_time->duration_us,
+ qh->host_interval, trans_time->start_schedule_us,
+ only_one_period);
+
+ if (us < 0)
+ return us;
+
+ trans_time->start_schedule_us = us;
+ return 0;
+}
+
+/**
+ * dwc2_hs_pmap_unschedule() - Undo work done by dwc2_hs_pmap_schedule()
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller.
+ * @qh: QH for the periodic transfer.
+ * @index: Transfer index
+ */
+static void dwc2_hs_pmap_unschedule(struct dwc2_hsotg *hsotg,
+ struct dwc2_qh *qh, int index)
+{
+ struct dwc2_hs_transfer_time *trans_time = qh->hs_transfers + index;
+
+ pmap_unschedule(hsotg->hs_periodic_bitmap,
+ DWC2_HS_PERIODIC_US_PER_UFRAME,
+ DWC2_HS_SCHEDULE_UFRAMES, trans_time->duration_us,
+ qh->host_interval, trans_time->start_schedule_us);
+}
+
+/**
+ * dwc2_uframe_schedule_split - Schedule a QH for a periodic split xfer.
+ *
+ * This is the most complicated thing in USB. We have to find matching time
+ * in both the global high speed schedule for the port and the low speed
+ * schedule for the TT associated with the given device.
+ *
+ * Being here means that the host must be running in high speed mode and the
+ * device is in low or full speed mode (and behind a hub).
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller.
+ * @qh: QH for the periodic transfer.
+ */
+static int dwc2_uframe_schedule_split(struct dwc2_hsotg *hsotg,
+ struct dwc2_qh *qh)
+{
+ int bytecount = qh->maxp_mult * qh->maxp;
+ int ls_search_slice;
+ int err = 0;
+ int host_interval_in_sched;
+
+ /*
+ * The interval (how often to repeat) in the actual host schedule.
+ * See pmap_schedule() for gcd() explanation.
+ */
+ host_interval_in_sched = gcd(qh->host_interval,
+ DWC2_HS_SCHEDULE_UFRAMES);
+
+ /*
+ * We always try to find space in the low speed schedule first, then
+ * try to find high speed time that matches. If we don't, we'll bump
+ * up the place we start searching in the low speed schedule and try
+ * again. To start we'll look right at the beginning of the low speed
+ * schedule.
+ *
+ * Note that this will tend to front-load the high speed schedule.
+ * We may eventually want to try to avoid this by either considering
+ * both schedules together or doing some sort of round robin.
+ */
+ ls_search_slice = 0;
+
+ while (ls_search_slice < DWC2_LS_SCHEDULE_SLICES) {
+ int start_s_uframe;
+ int ssplit_s_uframe;
+ int second_s_uframe;
+ int rel_uframe;
+ int first_count;
+ int middle_count;
+ int end_count;
+ int first_data_bytes;
+ int other_data_bytes;
+ int i;
+
+ if (qh->schedule_low_speed) {
+ err = dwc2_ls_pmap_schedule(hsotg, qh, ls_search_slice);
+
+ /*
+ * If we got an error here there's no other magic we
+ * can do, so bail. All the looping above is only
+ * helpful to redo things if we got a low speed slot
+ * and then couldn't find a matching high speed slot.
+ */
+ if (err)
+ return err;
+ } else {
+ /* Must be missing the tt structure? Why? */
+ WARN_ON_ONCE(1);
+ }
+
+ /*
+ * This will give us a number 0 - 7 if
+ * DWC2_LS_SCHEDULE_FRAMES == 1, or 0 - 15 if == 2, or ...
+ */
+ start_s_uframe = qh->ls_start_schedule_slice /
+ DWC2_SLICES_PER_UFRAME;
+
+ /* Get a number that's always 0 - 7 */
+ rel_uframe = (start_s_uframe % 8);
+
+ /*
+ * If we were going to start in uframe 7 then we would need to
+ * issue a start split in uframe 6, which spec says is not OK.
+ * Move on to the next full frame (assuming there is one).
+ *
+ * See 11.18.4 Host Split Transaction Scheduling Requirements
+ * bullet 1.
+ */
+ if (rel_uframe == 7) {
+ if (qh->schedule_low_speed)
+ dwc2_ls_pmap_unschedule(hsotg, qh);
+ ls_search_slice =
+ (qh->ls_start_schedule_slice /
+ DWC2_LS_PERIODIC_SLICES_PER_FRAME + 1) *
+ DWC2_LS_PERIODIC_SLICES_PER_FRAME;
+ continue;
+ }
+
+ /*
+ * For ISOC in:
+ * - start split (frame -1)
+ * - complete split w/ data (frame +1)
+ * - complete split w/ data (frame +2)
+ * - ...
+ * - complete split w/ data (frame +num_data_packets)
+ * - complete split w/ data (frame +num_data_packets+1)
+ * - complete split w/ data (frame +num_data_packets+2, max 8)
+ * ...though if frame was "0" then max is 7...
+ *
+ * For ISOC out we might need to do:
+ * - start split w/ data (frame -1)
+ * - start split w/ data (frame +0)
+ * - ...
+ * - start split w/ data (frame +num_data_packets-2)
+ *
+ * For INTERRUPT in we might need to do:
+ * - start split (frame -1)
+ * - complete split w/ data (frame +1)
+ * - complete split w/ data (frame +2)
+ * - complete split w/ data (frame +3, max 8)
+ *
+ * For INTERRUPT out we might need to do:
+ * - start split w/ data (frame -1)
+ * - complete split (frame +1)
+ * - complete split (frame +2)
+ * - complete split (frame +3, max 8)
+ *
+ * Start adjusting!
+ */
+ ssplit_s_uframe = (start_s_uframe +
+ host_interval_in_sched - 1) %
+ host_interval_in_sched;
+ if (qh->ep_type == USB_ENDPOINT_XFER_ISOC && !qh->ep_is_in)
+ second_s_uframe = start_s_uframe;
+ else
+ second_s_uframe = start_s_uframe + 1;
+
+ /* First data transfer might not be all 188 bytes. */
+ first_data_bytes = 188 -
+ DIV_ROUND_UP(188 * (qh->ls_start_schedule_slice %
+ DWC2_SLICES_PER_UFRAME),
+ DWC2_SLICES_PER_UFRAME);
+ if (first_data_bytes > bytecount)
+ first_data_bytes = bytecount;
+ other_data_bytes = bytecount - first_data_bytes;
+
+ /*
+ * For now, skip OUT xfers where first xfer is partial
+ *
+ * Main dwc2 code assumes:
+ * - INT transfers never get split in two.
+ * - ISOC transfers can always transfer 188 bytes the first
+ * time.
+ *
+ * Until that code is fixed, try again if the first transfer
+ * couldn't transfer everything.
+ *
+ * This code can be removed if/when the rest of dwc2 handles
+ * the above cases. Until it's fixed we just won't be able
+ * to schedule quite as tightly.
+ */
+ if (!qh->ep_is_in &&
+ (first_data_bytes != min_t(int, 188, bytecount))) {
+ dwc2_sch_dbg(hsotg,
+ "QH=%p avoiding broken 1st xfer (%d, %d)\n",
+ qh, first_data_bytes, bytecount);
+ if (qh->schedule_low_speed)
+ dwc2_ls_pmap_unschedule(hsotg, qh);
+ ls_search_slice = (start_s_uframe + 1) *
+ DWC2_SLICES_PER_UFRAME;
+ continue;
+ }
+
+ /* Start by assuming transfers for the bytes */
+ qh->num_hs_transfers = 1 + DIV_ROUND_UP(other_data_bytes, 188);
+
+ /*
+ * Everything except ISOC OUT has extra transfers. Rules are
+ * complicated. See 11.18.4 Host Split Transaction Scheduling
+ * Requirements bullet 3.
+ */
+ if (qh->ep_type == USB_ENDPOINT_XFER_INT) {
+ if (rel_uframe == 6)
+ qh->num_hs_transfers += 2;
+ else
+ qh->num_hs_transfers += 3;
+
+ if (qh->ep_is_in) {
+ /*
+ * First is start split, middle/end is data.
+ * Allocate full data bytes for all data.
+ */
+ first_count = 4;
+ middle_count = bytecount;
+ end_count = bytecount;
+ } else {
+ /*
+ * First is data, middle/end is complete.
+ * First transfer and second can have data.
+ * Rest should just have complete split.
+ */
+ first_count = first_data_bytes;
+ middle_count = max_t(int, 4, other_data_bytes);
+ end_count = 4;
+ }
+ } else {
+ if (qh->ep_is_in) {
+ int last;
+
+ /* Account for the start split */
+ qh->num_hs_transfers++;
+
+ /* Calculate "L" value from spec */
+ last = rel_uframe + qh->num_hs_transfers + 1;
+
+ /* Start with basic case */
+ if (last <= 6)
+ qh->num_hs_transfers += 2;
+ else
+ qh->num_hs_transfers += 1;
+
+ /* Adjust downwards */
+ if (last >= 6 && rel_uframe == 0)
+ qh->num_hs_transfers--;
+
+ /* 1st = start; rest can contain data */
+ first_count = 4;
+ middle_count = min_t(int, 188, bytecount);
+ end_count = middle_count;
+ } else {
+ /* All contain data, last might be smaller */
+ first_count = first_data_bytes;
+ middle_count = min_t(int, 188,
+ other_data_bytes);
+ end_count = other_data_bytes % 188;
+ }
+ }
+
+ /* Assign durations per uFrame */
+ qh->hs_transfers[0].duration_us = HS_USECS_ISO(first_count);
+ for (i = 1; i < qh->num_hs_transfers - 1; i++)
+ qh->hs_transfers[i].duration_us =
+ HS_USECS_ISO(middle_count);
+ if (qh->num_hs_transfers > 1)
+ qh->hs_transfers[qh->num_hs_transfers - 1].duration_us =
+ HS_USECS_ISO(end_count);
+
+ /*
+ * Assign start us. The call below to dwc2_hs_pmap_schedule()
+ * will start with these numbers but may adjust within the same
+ * microframe.
+ */
+ qh->hs_transfers[0].start_schedule_us =
+ ssplit_s_uframe * DWC2_HS_PERIODIC_US_PER_UFRAME;
+ for (i = 1; i < qh->num_hs_transfers; i++)
+ qh->hs_transfers[i].start_schedule_us =
+ ((second_s_uframe + i - 1) %
+ DWC2_HS_SCHEDULE_UFRAMES) *
+ DWC2_HS_PERIODIC_US_PER_UFRAME;
+
+ /* Try to schedule with filled in hs_transfers above */
+ for (i = 0; i < qh->num_hs_transfers; i++) {
+ err = dwc2_hs_pmap_schedule(hsotg, qh, true, i);
+ if (err)
+ break;
+ }
+
+ /* If we scheduled all w/out breaking out then we're all good */
+ if (i == qh->num_hs_transfers)
+ break;
+
+ for (; i >= 0; i--)
+ dwc2_hs_pmap_unschedule(hsotg, qh, i);
+
+ if (qh->schedule_low_speed)
+ dwc2_ls_pmap_unschedule(hsotg, qh);
+
+ /* Try again starting in the next microframe */
+ ls_search_slice = (start_s_uframe + 1) * DWC2_SLICES_PER_UFRAME;
+ }
+
+ if (ls_search_slice >= DWC2_LS_SCHEDULE_SLICES)
+ return -ENOSPC;
+
+ return 0;
+}
+
+/**
+ * dwc2_uframe_schedule_hs - Schedule a QH for a periodic high speed xfer.
+ *
+ * Basically this just wraps dwc2_hs_pmap_schedule() to provide a clean
+ * interface.
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller.
+ * @qh: QH for the periodic transfer.
+ */
+static int dwc2_uframe_schedule_hs(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
+{
+ /* In non-split host and device time are the same */
+ WARN_ON(qh->host_us != qh->device_us);
+ WARN_ON(qh->host_interval != qh->device_interval);
+ WARN_ON(qh->num_hs_transfers != 1);
+
+ /* We'll have one transfer; init start to 0 before calling scheduler */
+ qh->hs_transfers[0].start_schedule_us = 0;
+ qh->hs_transfers[0].duration_us = qh->host_us;
+
+ return dwc2_hs_pmap_schedule(hsotg, qh, false, 0);
+}
+
+/**
+ * dwc2_uframe_schedule_ls - Schedule a QH for a periodic low/full speed xfer.
+ *
+ * Basically this just wraps dwc2_ls_pmap_schedule() to provide a clean
+ * interface.
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller.
+ * @qh: QH for the periodic transfer.
+ */
+static int dwc2_uframe_schedule_ls(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
+{
+ /* In non-split host and device time are the same */
+ WARN_ON(qh->host_us != qh->device_us);
+ WARN_ON(qh->host_interval != qh->device_interval);
+ WARN_ON(!qh->schedule_low_speed);
+
+ /* Run on the main low speed schedule (no split = no hub = no TT) */
+ return dwc2_ls_pmap_schedule(hsotg, qh, 0);
+}
+
+/**
+ * dwc2_uframe_schedule - Schedule a QH for a periodic xfer.
+ *
+ * Calls one of the 3 sub-function depending on what type of transfer this QH
+ * is for. Also adds some printing.
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller.
+ * @qh: QH for the periodic transfer.
+ */
+static int dwc2_uframe_schedule(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
+{
+ int ret;
+
+ if (qh->dev_speed == USB_SPEED_HIGH)
+ ret = dwc2_uframe_schedule_hs(hsotg, qh);
+ else if (!qh->do_split)
+ ret = dwc2_uframe_schedule_ls(hsotg, qh);
+ else
+ ret = dwc2_uframe_schedule_split(hsotg, qh);
+
+ if (ret)
+ dwc2_sch_dbg(hsotg, "QH=%p Failed to schedule %d\n", qh, ret);
+ else
+ dwc2_qh_schedule_print(hsotg, qh);
+
+ return ret;
+}
+
+/**
+ * dwc2_uframe_unschedule - Undoes dwc2_uframe_schedule().
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller.
+ * @qh: QH for the periodic transfer.
+ */
+static void dwc2_uframe_unschedule(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
+{
+ int i;
+
+ for (i = 0; i < qh->num_hs_transfers; i++)
+ dwc2_hs_pmap_unschedule(hsotg, qh, i);
+
+ if (qh->schedule_low_speed)
+ dwc2_ls_pmap_unschedule(hsotg, qh);
+
+ dwc2_sch_dbg(hsotg, "QH=%p Unscheduled\n", qh);
+}
+
+/**
+ * dwc2_pick_first_frame() - Choose 1st frame for qh that's already scheduled
+ *
+ * Takes a qh that has already been scheduled (which means we know we have the
+ * bandwdith reserved for us) and set the next_active_frame and the
+ * start_active_frame.
+ *
+ * This is expected to be called on qh's that weren't previously actively
+ * running. It just picks the next frame that we can fit into without any
+ * thought about the past.
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller
+ * @qh: QH for a periodic endpoint
+ *
+ */
+static void dwc2_pick_first_frame(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
+{
+ u16 frame_number;
+ u16 earliest_frame;
+ u16 next_active_frame;
+ u16 relative_frame;
+ u16 interval;
+
+ /*
+ * Use the real frame number rather than the cached value as of the
+ * last SOF to give us a little extra slop.
+ */
+ frame_number = dwc2_hcd_get_frame_number(hsotg);
+
+ /*
+ * We wouldn't want to start any earlier than the next frame just in
+ * case the frame number ticks as we're doing this calculation.
+ *
+ * NOTE: if we could quantify how long till we actually get scheduled
+ * we might be able to avoid the "+ 1" by looking at the upper part of
+ * HFNUM (the FRREM field). For now we'll just use the + 1 though.
+ */
+ earliest_frame = dwc2_frame_num_inc(frame_number, 1);
+ next_active_frame = earliest_frame;
+
+ /* Get the "no microframe schduler" out of the way... */
+ if (!hsotg->params.uframe_sched) {
+ if (qh->do_split)
+ /* Splits are active at microframe 0 minus 1 */
+ next_active_frame |= 0x7;
+ goto exit;
+ }
+
+ if (qh->dev_speed == USB_SPEED_HIGH || qh->do_split) {
+ /*
+ * We're either at high speed or we're doing a split (which
+ * means we're talking high speed to a hub). In any case
+ * the first frame should be based on when the first scheduled
+ * event is.
+ */
+ WARN_ON(qh->num_hs_transfers < 1);
+
+ relative_frame = qh->hs_transfers[0].start_schedule_us /
+ DWC2_HS_PERIODIC_US_PER_UFRAME;
+
+ /* Adjust interval as per high speed schedule */
+ interval = gcd(qh->host_interval, DWC2_HS_SCHEDULE_UFRAMES);
+
+ } else {
+ /*
+ * Low or full speed directly on dwc2. Just about the same
+ * as high speed but on a different schedule and with slightly
+ * different adjustments. Note that this works because when
+ * the host and device are both low speed then frames in the
+ * controller tick at low speed.
+ */
+ relative_frame = qh->ls_start_schedule_slice /
+ DWC2_LS_PERIODIC_SLICES_PER_FRAME;
+ interval = gcd(qh->host_interval, DWC2_LS_SCHEDULE_FRAMES);
+ }
+
+ /* Scheduler messed up if frame is past interval */
+ WARN_ON(relative_frame >= interval);
+
+ /*
+ * We know interval must divide (HFNUM_MAX_FRNUM + 1) now that we've
+ * done the gcd(), so it's safe to move to the beginning of the current
+ * interval like this.
+ *
+ * After this we might be before earliest_frame, but don't worry,
+ * we'll fix it...
+ */
+ next_active_frame = (next_active_frame / interval) * interval;
+
+ /*
+ * Actually choose to start at the frame number we've been
+ * scheduled for.
+ */
+ next_active_frame = dwc2_frame_num_inc(next_active_frame,
+ relative_frame);
+
+ /*
+ * We actually need 1 frame before since the next_active_frame is
+ * the frame number we'll be put on the ready list and we won't be on
+ * the bus until 1 frame later.
+ */
+ next_active_frame = dwc2_frame_num_dec(next_active_frame, 1);
+
+ /*
+ * By now we might actually be before the earliest_frame. Let's move
+ * up intervals until we're not.
+ */
+ while (dwc2_frame_num_gt(earliest_frame, next_active_frame))
+ next_active_frame = dwc2_frame_num_inc(next_active_frame,
+ interval);
+
+exit:
+ qh->next_active_frame = next_active_frame;
+ qh->start_active_frame = next_active_frame;
+
+ dwc2_sch_vdbg(hsotg, "QH=%p First fn=%04x nxt=%04x\n",
+ qh, frame_number, qh->next_active_frame);
+}
+
+/**
+ * dwc2_do_reserve() - Make a periodic reservation
+ *
+ * Try to allocate space in the periodic schedule. Depending on parameters
+ * this might use the microframe scheduler or the dumb scheduler.
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller
+ * @qh: QH for the periodic transfer.
+ *
+ * Returns: 0 upon success; error upon failure.
+ */
+static int dwc2_do_reserve(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
+{
+ int status;
+
+ if (hsotg->params.uframe_sched) {
+ status = dwc2_uframe_schedule(hsotg, qh);
+ } else {
+ status = dwc2_periodic_channel_available(hsotg);
+ if (status) {
+ dev_info(hsotg->dev,
+ "%s: No host channel available for periodic transfer\n",
+ __func__);
+ return status;
+ }
+
+ status = dwc2_check_periodic_bandwidth(hsotg, qh);
+ }
+
+ if (status) {
+ dev_dbg(hsotg->dev,
+ "%s: Insufficient periodic bandwidth for periodic transfer\n",
+ __func__);
+ return status;
+ }
+
+ if (!hsotg->params.uframe_sched)
+ /* Reserve periodic channel */
+ hsotg->periodic_channels++;
+
+ /* Update claimed usecs per (micro)frame */
+ hsotg->periodic_usecs += qh->host_us;
+
+ dwc2_pick_first_frame(hsotg, qh);
+
+ return 0;
+}
+
+/**
+ * dwc2_do_unreserve() - Actually release the periodic reservation
+ *
+ * This function actually releases the periodic bandwidth that was reserved
+ * by the given qh.
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller
+ * @qh: QH for the periodic transfer.
+ */
+static void dwc2_do_unreserve(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
+{
+ assert_spin_locked(&hsotg->lock);
+
+ WARN_ON(!qh->unreserve_pending);
+
+ /* No more unreserve pending--we're doing it */
+ qh->unreserve_pending = false;
+
+ if (WARN_ON(!list_empty(&qh->qh_list_entry)))
+ list_del_init(&qh->qh_list_entry);
+
+ /* Update claimed usecs per (micro)frame */
+ hsotg->periodic_usecs -= qh->host_us;
+
+ if (hsotg->params.uframe_sched) {
+ dwc2_uframe_unschedule(hsotg, qh);
+ } else {
+ /* Release periodic channel reservation */
+ hsotg->periodic_channels--;
+ }
+}
+
+/**
+ * dwc2_unreserve_timer_fn() - Timer function to release periodic reservation
+ *
+ * According to the kernel doc for usb_submit_urb() (specifically the part about
+ * "Reserved Bandwidth Transfers"), we need to keep a reservation active as
+ * long as a device driver keeps submitting. Since we're using HCD_BH to give
+ * back the URB we need to give the driver a little bit of time before we
+ * release the reservation. This worker is called after the appropriate
+ * delay.
+ *
+ * @t: Address to a qh unreserve_work.
+ */
+static void dwc2_unreserve_timer_fn(struct timer_list *t)
+{
+ struct dwc2_qh *qh = from_timer(qh, t, unreserve_timer);
+ struct dwc2_hsotg *hsotg = qh->hsotg;
+ unsigned long flags;
+
+ /*
+ * Wait for the lock, or for us to be scheduled again. We
+ * could be scheduled again if:
+ * - We started executing but didn't get the lock yet.
+ * - A new reservation came in, but cancel didn't take effect
+ * because we already started executing.
+ * - The timer has been kicked again.
+ * In that case cancel and wait for the next call.
+ */
+ while (!spin_trylock_irqsave(&hsotg->lock, flags)) {
+ if (timer_pending(&qh->unreserve_timer))
+ return;
+ }
+
+ /*
+ * Might be no more unreserve pending if:
+ * - We started executing but didn't get the lock yet.
+ * - A new reservation came in, but cancel didn't take effect
+ * because we already started executing.
+ *
+ * We can't put this in the loop above because unreserve_pending needs
+ * to be accessed under lock, so we can only check it once we got the
+ * lock.
+ */
+ if (qh->unreserve_pending)
+ dwc2_do_unreserve(hsotg, qh);
+
+ spin_unlock_irqrestore(&hsotg->lock, flags);
+}
+
+/**
+ * dwc2_check_max_xfer_size() - Checks that the max transfer size allowed in a
+ * host channel is large enough to handle the maximum data transfer in a single
+ * (micro)frame for a periodic transfer
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller
+ * @qh: QH for a periodic endpoint
+ *
+ * Return: 0 if successful, negative error code otherwise
+ */
+static int dwc2_check_max_xfer_size(struct dwc2_hsotg *hsotg,
+ struct dwc2_qh *qh)
+{
+ u32 max_xfer_size;
+ u32 max_channel_xfer_size;
+ int status = 0;
+
+ max_xfer_size = qh->maxp * qh->maxp_mult;
+ max_channel_xfer_size = hsotg->params.max_transfer_size;
+
+ if (max_xfer_size > max_channel_xfer_size) {
+ dev_err(hsotg->dev,
+ "%s: Periodic xfer length %d > max xfer length for channel %d\n",
+ __func__, max_xfer_size, max_channel_xfer_size);
+ status = -ENOSPC;
+ }
+
+ return status;
+}
+
+/**
+ * dwc2_schedule_periodic() - Schedules an interrupt or isochronous transfer in
+ * the periodic schedule
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller
+ * @qh: QH for the periodic transfer. The QH should already contain the
+ * scheduling information.
+ *
+ * Return: 0 if successful, negative error code otherwise
+ */
+static int dwc2_schedule_periodic(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
+{
+ int status;
+
+ status = dwc2_check_max_xfer_size(hsotg, qh);
+ if (status) {
+ dev_dbg(hsotg->dev,
+ "%s: Channel max transfer size too small for periodic transfer\n",
+ __func__);
+ return status;
+ }
+
+ /* Cancel pending unreserve; if canceled OK, unreserve was pending */
+ if (del_timer(&qh->unreserve_timer))
+ WARN_ON(!qh->unreserve_pending);
+
+ /*
+ * Only need to reserve if there's not an unreserve pending, since if an
+ * unreserve is pending then by definition our old reservation is still
+ * valid. Unreserve might still be pending even if we didn't cancel if
+ * dwc2_unreserve_timer_fn() already started. Code in the timer handles
+ * that case.
+ */
+ if (!qh->unreserve_pending) {
+ status = dwc2_do_reserve(hsotg, qh);
+ if (status)
+ return status;
+ } else {
+ /*
+ * It might have been a while, so make sure that frame_number
+ * is still good. Note: we could also try to use the similar
+ * dwc2_next_periodic_start() but that schedules much more
+ * tightly and we might need to hurry and queue things up.
+ */
+ if (dwc2_frame_num_le(qh->next_active_frame,
+ hsotg->frame_number))
+ dwc2_pick_first_frame(hsotg, qh);
+ }
+
+ qh->unreserve_pending = 0;
+
+ if (hsotg->params.dma_desc_enable)
+ /* Don't rely on SOF and start in ready schedule */
+ list_add_tail(&qh->qh_list_entry, &hsotg->periodic_sched_ready);
+ else
+ /* Always start in inactive schedule */
+ list_add_tail(&qh->qh_list_entry,
+ &hsotg->periodic_sched_inactive);
+
+ return 0;
+}
+
+/**
+ * dwc2_deschedule_periodic() - Removes an interrupt or isochronous transfer
+ * from the periodic schedule
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller
+ * @qh: QH for the periodic transfer
+ */
+static void dwc2_deschedule_periodic(struct dwc2_hsotg *hsotg,
+ struct dwc2_qh *qh)
+{
+ bool did_modify;
+
+ assert_spin_locked(&hsotg->lock);
+
+ /*
+ * Schedule the unreserve to happen in a little bit. Cases here:
+ * - Unreserve worker might be sitting there waiting to grab the lock.
+ * In this case it will notice it's been schedule again and will
+ * quit.
+ * - Unreserve worker might not be scheduled.
+ *
+ * We should never already be scheduled since dwc2_schedule_periodic()
+ * should have canceled the scheduled unreserve timer (hence the
+ * warning on did_modify).
+ *
+ * We add + 1 to the timer to guarantee that at least 1 jiffy has
+ * passed (otherwise if the jiffy counter might tick right after we
+ * read it and we'll get no delay).
+ */
+ did_modify = mod_timer(&qh->unreserve_timer,
+ jiffies + DWC2_UNRESERVE_DELAY + 1);
+ WARN_ON(did_modify);
+ qh->unreserve_pending = 1;
+
+ list_del_init(&qh->qh_list_entry);
+}
+
+/**
+ * dwc2_wait_timer_fn() - Timer function to re-queue after waiting
+ *
+ * As per the spec, a NAK indicates that "a function is temporarily unable to
+ * transmit or receive data, but will eventually be able to do so without need
+ * of host intervention".
+ *
+ * That means that when we encounter a NAK we're supposed to retry.
+ *
+ * ...but if we retry right away (from the interrupt handler that saw the NAK)
+ * then we can end up with an interrupt storm (if the other side keeps NAKing
+ * us) because on slow enough CPUs it could take us longer to get out of the
+ * interrupt routine than it takes for the device to send another NAK. That
+ * leads to a constant stream of NAK interrupts and the CPU locks.
+ *
+ * ...so instead of retrying right away in the case of a NAK we'll set a timer
+ * to retry some time later. This function handles that timer and moves the
+ * qh back to the "inactive" list, then queues transactions.
+ *
+ * @t: Pointer to wait_timer in a qh.
+ *
+ * Return: HRTIMER_NORESTART to not automatically restart this timer.
+ */
+static enum hrtimer_restart dwc2_wait_timer_fn(struct hrtimer *t)
+{
+ struct dwc2_qh *qh = container_of(t, struct dwc2_qh, wait_timer);
+ struct dwc2_hsotg *hsotg = qh->hsotg;
+ unsigned long flags;
+
+ spin_lock_irqsave(&hsotg->lock, flags);
+
+ /*
+ * We'll set wait_timer_cancel to true if we want to cancel this
+ * operation in dwc2_hcd_qh_unlink().
+ */
+ if (!qh->wait_timer_cancel) {
+ enum dwc2_transaction_type tr_type;
+
+ qh->want_wait = false;
+
+ list_move(&qh->qh_list_entry,
+ &hsotg->non_periodic_sched_inactive);
+
+ tr_type = dwc2_hcd_select_transactions(hsotg);
+ if (tr_type != DWC2_TRANSACTION_NONE)
+ dwc2_hcd_queue_transactions(hsotg, tr_type);
+ }
+
+ spin_unlock_irqrestore(&hsotg->lock, flags);
+ return HRTIMER_NORESTART;
+}
+
+/**
+ * dwc2_qh_init() - Initializes a QH structure
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller
+ * @qh: The QH to init
+ * @urb: Holds the information about the device/endpoint needed to initialize
+ * the QH
+ * @mem_flags: Flags for allocating memory.
+ */
+static void dwc2_qh_init(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
+ struct dwc2_hcd_urb *urb, gfp_t mem_flags)
+{
+ int dev_speed = dwc2_host_get_speed(hsotg, urb->priv);
+ u8 ep_type = dwc2_hcd_get_pipe_type(&urb->pipe_info);
+ bool ep_is_in = !!dwc2_hcd_is_pipe_in(&urb->pipe_info);
+ bool ep_is_isoc = (ep_type == USB_ENDPOINT_XFER_ISOC);
+ bool ep_is_int = (ep_type == USB_ENDPOINT_XFER_INT);
+ u32 hprt = dwc2_readl(hsotg, HPRT0);
+ u32 prtspd = (hprt & HPRT0_SPD_MASK) >> HPRT0_SPD_SHIFT;
+ bool do_split = (prtspd == HPRT0_SPD_HIGH_SPEED &&
+ dev_speed != USB_SPEED_HIGH);
+ int maxp = dwc2_hcd_get_maxp(&urb->pipe_info);
+ int maxp_mult = dwc2_hcd_get_maxp_mult(&urb->pipe_info);
+ int bytecount = maxp_mult * maxp;
+ char *speed, *type;
+
+ /* Initialize QH */
+ qh->hsotg = hsotg;
+ timer_setup(&qh->unreserve_timer, dwc2_unreserve_timer_fn, 0);
+ hrtimer_init(&qh->wait_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ qh->wait_timer.function = &dwc2_wait_timer_fn;
+ qh->ep_type = ep_type;
+ qh->ep_is_in = ep_is_in;
+
+ qh->data_toggle = DWC2_HC_PID_DATA0;
+ qh->maxp = maxp;
+ qh->maxp_mult = maxp_mult;
+ INIT_LIST_HEAD(&qh->qtd_list);
+ INIT_LIST_HEAD(&qh->qh_list_entry);
+
+ qh->do_split = do_split;
+ qh->dev_speed = dev_speed;
+
+ if (ep_is_int || ep_is_isoc) {
+ /* Compute scheduling parameters once and save them */
+ int host_speed = do_split ? USB_SPEED_HIGH : dev_speed;
+ struct dwc2_tt *dwc_tt = dwc2_host_get_tt_info(hsotg, urb->priv,
+ mem_flags,
+ &qh->ttport);
+ int device_ns;
+
+ qh->dwc_tt = dwc_tt;
+
+ qh->host_us = NS_TO_US(usb_calc_bus_time(host_speed, ep_is_in,
+ ep_is_isoc, bytecount));
+ device_ns = usb_calc_bus_time(dev_speed, ep_is_in,
+ ep_is_isoc, bytecount);
+
+ if (do_split && dwc_tt)
+ device_ns += dwc_tt->usb_tt->think_time;
+ qh->device_us = NS_TO_US(device_ns);
+
+ qh->device_interval = urb->interval;
+ qh->host_interval = urb->interval * (do_split ? 8 : 1);
+
+ /*
+ * Schedule low speed if we're running the host in low or
+ * full speed OR if we've got a "TT" to deal with to access this
+ * device.
+ */
+ qh->schedule_low_speed = prtspd != HPRT0_SPD_HIGH_SPEED ||
+ dwc_tt;
+
+ if (do_split) {
+ /* We won't know num transfers until we schedule */
+ qh->num_hs_transfers = -1;
+ } else if (dev_speed == USB_SPEED_HIGH) {
+ qh->num_hs_transfers = 1;
+ } else {
+ qh->num_hs_transfers = 0;
+ }
+
+ /* We'll schedule later when we have something to do */
+ }
+
+ switch (dev_speed) {
+ case USB_SPEED_LOW:
+ speed = "low";
+ break;
+ case USB_SPEED_FULL:
+ speed = "full";
+ break;
+ case USB_SPEED_HIGH:
+ speed = "high";
+ break;
+ default:
+ speed = "?";
+ break;
+ }
+
+ switch (qh->ep_type) {
+ case USB_ENDPOINT_XFER_ISOC:
+ type = "isochronous";
+ break;
+ case USB_ENDPOINT_XFER_INT:
+ type = "interrupt";
+ break;
+ case USB_ENDPOINT_XFER_CONTROL:
+ type = "control";
+ break;
+ case USB_ENDPOINT_XFER_BULK:
+ type = "bulk";
+ break;
+ default:
+ type = "?";
+ break;
+ }
+
+ dwc2_sch_dbg(hsotg, "QH=%p Init %s, %s speed, %d bytes:\n", qh, type,
+ speed, bytecount);
+ dwc2_sch_dbg(hsotg, "QH=%p ...addr=%d, ep=%d, %s\n", qh,
+ dwc2_hcd_get_dev_addr(&urb->pipe_info),
+ dwc2_hcd_get_ep_num(&urb->pipe_info),
+ ep_is_in ? "IN" : "OUT");
+ if (ep_is_int || ep_is_isoc) {
+ dwc2_sch_dbg(hsotg,
+ "QH=%p ...duration: host=%d us, device=%d us\n",
+ qh, qh->host_us, qh->device_us);
+ dwc2_sch_dbg(hsotg, "QH=%p ...interval: host=%d, device=%d\n",
+ qh, qh->host_interval, qh->device_interval);
+ if (qh->schedule_low_speed)
+ dwc2_sch_dbg(hsotg, "QH=%p ...low speed schedule=%p\n",
+ qh, dwc2_get_ls_map(hsotg, qh));
+ }
+}
+
+/**
+ * dwc2_hcd_qh_create() - Allocates and initializes a QH
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller
+ * @urb: Holds the information about the device/endpoint needed
+ * to initialize the QH
+ * @mem_flags: Flags for allocating memory.
+ *
+ * Return: Pointer to the newly allocated QH, or NULL on error
+ */
+struct dwc2_qh *dwc2_hcd_qh_create(struct dwc2_hsotg *hsotg,
+ struct dwc2_hcd_urb *urb,
+ gfp_t mem_flags)
+{
+ struct dwc2_qh *qh;
+
+ if (!urb->priv)
+ return NULL;
+
+ /* Allocate memory */
+ qh = kzalloc(sizeof(*qh), mem_flags);
+ if (!qh)
+ return NULL;
+
+ dwc2_qh_init(hsotg, qh, urb, mem_flags);
+
+ if (hsotg->params.dma_desc_enable &&
+ dwc2_hcd_qh_init_ddma(hsotg, qh, mem_flags) < 0) {
+ dwc2_hcd_qh_free(hsotg, qh);
+ return NULL;
+ }
+
+ return qh;
+}
+
+/**
+ * dwc2_hcd_qh_free() - Frees the QH
+ *
+ * @hsotg: HCD instance
+ * @qh: The QH to free
+ *
+ * QH should already be removed from the list. QTD list should already be empty
+ * if called from URB Dequeue.
+ *
+ * Must NOT be called with interrupt disabled or spinlock held
+ */
+void dwc2_hcd_qh_free(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
+{
+ /* Make sure any unreserve work is finished. */
+ if (del_timer_sync(&qh->unreserve_timer)) {
+ unsigned long flags;
+
+ spin_lock_irqsave(&hsotg->lock, flags);
+ dwc2_do_unreserve(hsotg, qh);
+ spin_unlock_irqrestore(&hsotg->lock, flags);
+ }
+
+ /*
+ * We don't have the lock so we can safely wait until the wait timer
+ * finishes. Of course, at this point in time we'd better have set
+ * wait_timer_active to false so if this timer was still pending it
+ * won't do anything anyway, but we want it to finish before we free
+ * memory.
+ */
+ hrtimer_cancel(&qh->wait_timer);
+
+ dwc2_host_put_tt_info(hsotg, qh->dwc_tt);
+
+ if (qh->desc_list)
+ dwc2_hcd_qh_free_ddma(hsotg, qh);
+ else if (hsotg->unaligned_cache && qh->dw_align_buf)
+ kmem_cache_free(hsotg->unaligned_cache, qh->dw_align_buf);
+
+ kfree(qh);
+}
+
+/**
+ * dwc2_hcd_qh_add() - Adds a QH to either the non periodic or periodic
+ * schedule if it is not already in the schedule. If the QH is already in
+ * the schedule, no action is taken.
+ *
+ * @hsotg: The HCD state structure for the DWC OTG controller
+ * @qh: The QH to add
+ *
+ * Return: 0 if successful, negative error code otherwise
+ */
+int dwc2_hcd_qh_add(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
+{
+ int status;
+ u32 intr_mask;
+ ktime_t delay;
+
+ if (dbg_qh(qh))
+ dev_vdbg(hsotg->dev, "%s()\n", __func__);
+
+ if (!list_empty(&qh->qh_list_entry))
+ /* QH already in a schedule */
+ return 0;
+
+ /* Add the new QH to the appropriate schedule */
+ if (dwc2_qh_is_non_per(qh)) {
+ /* Schedule right away */
+ qh->start_active_frame = hsotg->frame_number;
+ qh->next_active_frame = qh->start_active_frame;
+
+ if (qh->want_wait) {
+ list_add_tail(&qh->qh_list_entry,
+ &hsotg->non_periodic_sched_waiting);
+ qh->wait_timer_cancel = false;
+ delay = ktime_set(0, DWC2_RETRY_WAIT_DELAY);
+ hrtimer_start(&qh->wait_timer, delay, HRTIMER_MODE_REL);
+ } else {
+ list_add_tail(&qh->qh_list_entry,
+ &hsotg->non_periodic_sched_inactive);
+ }
+ return 0;
+ }
+
+ status = dwc2_schedule_periodic(hsotg, qh);
+ if (status)
+ return status;
+ if (!hsotg->periodic_qh_count) {
+ intr_mask = dwc2_readl(hsotg, GINTMSK);
+ intr_mask |= GINTSTS_SOF;
+ dwc2_writel(hsotg, intr_mask, GINTMSK);
+ }
+ hsotg->periodic_qh_count++;
+
+ return 0;
+}
+
+/**
+ * dwc2_hcd_qh_unlink() - Removes a QH from either the non-periodic or periodic
+ * schedule. Memory is not freed.
+ *
+ * @hsotg: The HCD state structure
+ * @qh: QH to remove from schedule
+ */
+void dwc2_hcd_qh_unlink(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
+{
+ u32 intr_mask;
+
+ dev_vdbg(hsotg->dev, "%s()\n", __func__);
+
+ /* If the wait_timer is pending, this will stop it from acting */
+ qh->wait_timer_cancel = true;
+
+ if (list_empty(&qh->qh_list_entry))
+ /* QH is not in a schedule */
+ return;
+
+ if (dwc2_qh_is_non_per(qh)) {
+ if (hsotg->non_periodic_qh_ptr == &qh->qh_list_entry)
+ hsotg->non_periodic_qh_ptr =
+ hsotg->non_periodic_qh_ptr->next;
+ list_del_init(&qh->qh_list_entry);
+ return;
+ }
+
+ dwc2_deschedule_periodic(hsotg, qh);
+ hsotg->periodic_qh_count--;
+ if (!hsotg->periodic_qh_count &&
+ !hsotg->params.dma_desc_enable) {
+ intr_mask = dwc2_readl(hsotg, GINTMSK);
+ intr_mask &= ~GINTSTS_SOF;
+ dwc2_writel(hsotg, intr_mask, GINTMSK);
+ }
+}
+
+/**
+ * dwc2_next_for_periodic_split() - Set next_active_frame midway thru a split.
+ *
+ * This is called for setting next_active_frame for periodic splits for all but
+ * the first packet of the split. Confusing? I thought so...
+ *
+ * Periodic splits are single low/full speed transfers that we end up splitting
+ * up into several high speed transfers. They always fit into one full (1 ms)
+ * frame but might be split over several microframes (125 us each). We to put
+ * each of the parts on a very specific high speed frame.
+ *
+ * This function figures out where the next active uFrame needs to be.
+ *
+ * @hsotg: The HCD state structure
+ * @qh: QH for the periodic transfer.
+ * @frame_number: The current frame number.
+ *
+ * Return: number missed by (or 0 if we didn't miss).
+ */
+static int dwc2_next_for_periodic_split(struct dwc2_hsotg *hsotg,
+ struct dwc2_qh *qh, u16 frame_number)
+{
+ u16 old_frame = qh->next_active_frame;
+ u16 prev_frame_number = dwc2_frame_num_dec(frame_number, 1);
+ int missed = 0;
+ u16 incr;
+
+ /*
+ * See dwc2_uframe_schedule_split() for split scheduling.
+ *
+ * Basically: increment 1 normally, but 2 right after the start split
+ * (except for ISOC out).
+ */
+ if (old_frame == qh->start_active_frame &&
+ !(qh->ep_type == USB_ENDPOINT_XFER_ISOC && !qh->ep_is_in))
+ incr = 2;
+ else
+ incr = 1;
+
+ qh->next_active_frame = dwc2_frame_num_inc(old_frame, incr);
+
+ /*
+ * Note that it's OK for frame_number to be 1 frame past
+ * next_active_frame. Remember that next_active_frame is supposed to
+ * be 1 frame _before_ when we want to be scheduled. If we're 1 frame
+ * past it just means schedule ASAP.
+ *
+ * It's _not_ OK, however, if we're more than one frame past.
+ */
+ if (dwc2_frame_num_gt(prev_frame_number, qh->next_active_frame)) {
+ /*
+ * OOPS, we missed. That's actually pretty bad since
+ * the hub will be unhappy; try ASAP I guess.
+ */
+ missed = dwc2_frame_num_dec(prev_frame_number,
+ qh->next_active_frame);
+ qh->next_active_frame = frame_number;
+ }
+
+ return missed;
+}
+
+/**
+ * dwc2_next_periodic_start() - Set next_active_frame for next transfer start
+ *
+ * This is called for setting next_active_frame for a periodic transfer for
+ * all cases other than midway through a periodic split. This will also update
+ * start_active_frame.
+ *
+ * Since we _always_ keep start_active_frame as the start of the previous
+ * transfer this is normally pretty easy: we just add our interval to
+ * start_active_frame and we've got our answer.
+ *
+ * The tricks come into play if we miss. In that case we'll look for the next
+ * slot we can fit into.
+ *
+ * @hsotg: The HCD state structure
+ * @qh: QH for the periodic transfer.
+ * @frame_number: The current frame number.
+ *
+ * Return: number missed by (or 0 if we didn't miss).
+ */
+static int dwc2_next_periodic_start(struct dwc2_hsotg *hsotg,
+ struct dwc2_qh *qh, u16 frame_number)
+{
+ int missed = 0;
+ u16 interval = qh->host_interval;
+ u16 prev_frame_number = dwc2_frame_num_dec(frame_number, 1);
+
+ qh->start_active_frame = dwc2_frame_num_inc(qh->start_active_frame,
+ interval);
+
+ /*
+ * The dwc2_frame_num_gt() function used below won't work terribly well
+ * with if we just incremented by a really large intervals since the
+ * frame counter only goes to 0x3fff. It's terribly unlikely that we
+ * will have missed in this case anyway. Just go to exit. If we want
+ * to try to do better we'll need to keep track of a bigger counter
+ * somewhere in the driver and handle overflows.
+ */
+ if (interval >= 0x1000)
+ goto exit;
+
+ /*
+ * Test for misses, which is when it's too late to schedule.
+ *
+ * A few things to note:
+ * - We compare against prev_frame_number since start_active_frame
+ * and next_active_frame are always 1 frame before we want things
+ * to be active and we assume we can still get scheduled in the
+ * current frame number.
+ * - It's possible for start_active_frame (now incremented) to be
+ * next_active_frame if we got an EO MISS (even_odd miss) which
+ * basically means that we detected there wasn't enough time for
+ * the last packet and dwc2_hc_set_even_odd_frame() rescheduled us
+ * at the last second. We want to make sure we don't schedule
+ * another transfer for the same frame. My test webcam doesn't seem
+ * terribly upset by missing a transfer but really doesn't like when
+ * we do two transfers in the same frame.
+ * - Some misses are expected. Specifically, in order to work
+ * perfectly dwc2 really needs quite spectacular interrupt latency
+ * requirements. It needs to be able to handle its interrupts
+ * completely within 125 us of them being asserted. That not only
+ * means that the dwc2 interrupt handler needs to be fast but it
+ * means that nothing else in the system has to block dwc2 for a long
+ * time. We can help with the dwc2 parts of this, but it's hard to
+ * guarantee that a system will have interrupt latency < 125 us, so
+ * we have to be robust to some misses.
+ */
+ if (qh->start_active_frame == qh->next_active_frame ||
+ dwc2_frame_num_gt(prev_frame_number, qh->start_active_frame)) {
+ u16 ideal_start = qh->start_active_frame;
+ int periods_in_map;
+
+ /*
+ * Adjust interval as per gcd with map size.
+ * See pmap_schedule() for more details here.
+ */
+ if (qh->do_split || qh->dev_speed == USB_SPEED_HIGH)
+ periods_in_map = DWC2_HS_SCHEDULE_UFRAMES;
+ else
+ periods_in_map = DWC2_LS_SCHEDULE_FRAMES;
+ interval = gcd(interval, periods_in_map);
+
+ do {
+ qh->start_active_frame = dwc2_frame_num_inc(
+ qh->start_active_frame, interval);
+ } while (dwc2_frame_num_gt(prev_frame_number,
+ qh->start_active_frame));
+
+ missed = dwc2_frame_num_dec(qh->start_active_frame,
+ ideal_start);
+ }
+
+exit:
+ qh->next_active_frame = qh->start_active_frame;
+
+ return missed;
+}
+
+/*
+ * Deactivates a QH. For non-periodic QHs, removes the QH from the active
+ * non-periodic schedule. The QH is added to the inactive non-periodic
+ * schedule if any QTDs are still attached to the QH.
+ *
+ * For periodic QHs, the QH is removed from the periodic queued schedule. If
+ * there are any QTDs still attached to the QH, the QH is added to either the
+ * periodic inactive schedule or the periodic ready schedule and its next
+ * scheduled frame is calculated. The QH is placed in the ready schedule if
+ * the scheduled frame has been reached already. Otherwise it's placed in the
+ * inactive schedule. If there are no QTDs attached to the QH, the QH is
+ * completely removed from the periodic schedule.
+ */
+void dwc2_hcd_qh_deactivate(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
+ int sched_next_periodic_split)
+{
+ u16 old_frame = qh->next_active_frame;
+ u16 frame_number;
+ int missed;
+
+ if (dbg_qh(qh))
+ dev_vdbg(hsotg->dev, "%s()\n", __func__);
+
+ if (dwc2_qh_is_non_per(qh)) {
+ dwc2_hcd_qh_unlink(hsotg, qh);
+ if (!list_empty(&qh->qtd_list))
+ /* Add back to inactive/waiting non-periodic schedule */
+ dwc2_hcd_qh_add(hsotg, qh);
+ return;
+ }
+
+ /*
+ * Use the real frame number rather than the cached value as of the
+ * last SOF just to get us a little closer to reality. Note that
+ * means we don't actually know if we've already handled the SOF
+ * interrupt for this frame.
+ */
+ frame_number = dwc2_hcd_get_frame_number(hsotg);
+
+ if (sched_next_periodic_split)
+ missed = dwc2_next_for_periodic_split(hsotg, qh, frame_number);
+ else
+ missed = dwc2_next_periodic_start(hsotg, qh, frame_number);
+
+ dwc2_sch_vdbg(hsotg,
+ "QH=%p next(%d) fn=%04x, sch=%04x=>%04x (%+d) miss=%d %s\n",
+ qh, sched_next_periodic_split, frame_number, old_frame,
+ qh->next_active_frame,
+ dwc2_frame_num_dec(qh->next_active_frame, old_frame),
+ missed, missed ? "MISS" : "");
+
+ if (list_empty(&qh->qtd_list)) {
+ dwc2_hcd_qh_unlink(hsotg, qh);
+ return;
+ }
+
+ /*
+ * Remove from periodic_sched_queued and move to
+ * appropriate queue
+ *
+ * Note: we purposely use the frame_number from the "hsotg" structure
+ * since we know SOF interrupt will handle future frames.
+ */
+ if (dwc2_frame_num_le(qh->next_active_frame, hsotg->frame_number))
+ list_move_tail(&qh->qh_list_entry,
+ &hsotg->periodic_sched_ready);
+ else
+ list_move_tail(&qh->qh_list_entry,
+ &hsotg->periodic_sched_inactive);
+}
+
+/**
+ * dwc2_hcd_qtd_init() - Initializes a QTD structure
+ *
+ * @qtd: The QTD to initialize
+ * @urb: The associated URB
+ */
+void dwc2_hcd_qtd_init(struct dwc2_qtd *qtd, struct dwc2_hcd_urb *urb)
+{
+ qtd->urb = urb;
+ if (dwc2_hcd_get_pipe_type(&urb->pipe_info) ==
+ USB_ENDPOINT_XFER_CONTROL) {
+ /*
+ * The only time the QTD data toggle is used is on the data
+ * phase of control transfers. This phase always starts with
+ * DATA1.
+ */
+ qtd->data_toggle = DWC2_HC_PID_DATA1;
+ qtd->control_phase = DWC2_CONTROL_SETUP;
+ }
+
+ /* Start split */
+ qtd->complete_split = 0;
+ qtd->isoc_split_pos = DWC2_HCSPLT_XACTPOS_ALL;
+ qtd->isoc_split_offset = 0;
+ qtd->in_process = 0;
+
+ /* Store the qtd ptr in the urb to reference the QTD */
+ urb->qtd = qtd;
+}
+
+/**
+ * dwc2_hcd_qtd_add() - Adds a QTD to the QTD-list of a QH
+ * Caller must hold driver lock.
+ *
+ * @hsotg: The DWC HCD structure
+ * @qtd: The QTD to add
+ * @qh: Queue head to add qtd to
+ *
+ * Return: 0 if successful, negative error code otherwise
+ *
+ * If the QH to which the QTD is added is not currently scheduled, it is placed
+ * into the proper schedule based on its EP type.
+ */
+int dwc2_hcd_qtd_add(struct dwc2_hsotg *hsotg, struct dwc2_qtd *qtd,
+ struct dwc2_qh *qh)
+{
+ int retval;
+
+ if (unlikely(!qh)) {
+ dev_err(hsotg->dev, "%s: Invalid QH\n", __func__);
+ retval = -EINVAL;
+ goto fail;
+ }
+
+ retval = dwc2_hcd_qh_add(hsotg, qh);
+ if (retval)
+ goto fail;
+
+ qtd->qh = qh;
+ list_add_tail(&qtd->qtd_list_entry, &qh->qtd_list);
+
+ return 0;
+fail:
+ return retval;
+}