diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/usb/host/ohci-dbg.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/usb/host/ohci-dbg.c')
-rw-r--r-- | drivers/usb/host/ohci-dbg.c | 785 |
1 files changed, 785 insertions, 0 deletions
diff --git a/drivers/usb/host/ohci-dbg.c b/drivers/usb/host/ohci-dbg.c new file mode 100644 index 000000000..76bc8d563 --- /dev/null +++ b/drivers/usb/host/ohci-dbg.c @@ -0,0 +1,785 @@ +// SPDX-License-Identifier: GPL-1.0+ +/* + * OHCI HCD (Host Controller Driver) for USB. + * + * (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at> + * (C) Copyright 2000-2002 David Brownell <dbrownell@users.sourceforge.net> + * + * This file is licenced under the GPL. + */ + +/*-------------------------------------------------------------------------*/ + +#define edstring(ed_type) ({ char *temp; \ + switch (ed_type) { \ + case PIPE_CONTROL: temp = "ctrl"; break; \ + case PIPE_BULK: temp = "bulk"; break; \ + case PIPE_INTERRUPT: temp = "intr"; break; \ + default: temp = "isoc"; break; \ + } temp;}) +#define pipestring(pipe) edstring(usb_pipetype(pipe)) + + +#define ohci_dbg_sw(ohci, next, size, format, arg...) \ + do { \ + if (next != NULL) { \ + unsigned s_len; \ + s_len = scnprintf (*next, *size, format, ## arg ); \ + *size -= s_len; *next += s_len; \ + } else \ + ohci_dbg(ohci,format, ## arg ); \ + } while (0); + +/* Version for use where "next" is the address of a local variable */ +#define ohci_dbg_nosw(ohci, next, size, format, arg...) \ + do { \ + unsigned s_len; \ + s_len = scnprintf(*next, *size, format, ## arg); \ + *size -= s_len; *next += s_len; \ + } while (0); + + +static void ohci_dump_intr_mask ( + struct ohci_hcd *ohci, + char *label, + u32 mask, + char **next, + unsigned *size) +{ + ohci_dbg_sw (ohci, next, size, "%s 0x%08x%s%s%s%s%s%s%s%s%s\n", + label, + mask, + (mask & OHCI_INTR_MIE) ? " MIE" : "", + (mask & OHCI_INTR_OC) ? " OC" : "", + (mask & OHCI_INTR_RHSC) ? " RHSC" : "", + (mask & OHCI_INTR_FNO) ? " FNO" : "", + (mask & OHCI_INTR_UE) ? " UE" : "", + (mask & OHCI_INTR_RD) ? " RD" : "", + (mask & OHCI_INTR_SF) ? " SF" : "", + (mask & OHCI_INTR_WDH) ? " WDH" : "", + (mask & OHCI_INTR_SO) ? " SO" : "" + ); +} + +static void maybe_print_eds ( + struct ohci_hcd *ohci, + char *label, + u32 value, + char **next, + unsigned *size) +{ + if (value) + ohci_dbg_sw (ohci, next, size, "%s %08x\n", label, value); +} + +static char *hcfs2string (int state) +{ + switch (state) { + case OHCI_USB_RESET: return "reset"; + case OHCI_USB_RESUME: return "resume"; + case OHCI_USB_OPER: return "operational"; + case OHCI_USB_SUSPEND: return "suspend"; + } + return "?"; +} + +static const char *rh_state_string(struct ohci_hcd *ohci) +{ + switch (ohci->rh_state) { + case OHCI_RH_HALTED: + return "halted"; + case OHCI_RH_SUSPENDED: + return "suspended"; + case OHCI_RH_RUNNING: + return "running"; + } + return "?"; +} + +// dump control and status registers +static void +ohci_dump_status (struct ohci_hcd *controller, char **next, unsigned *size) +{ + struct ohci_regs __iomem *regs = controller->regs; + u32 temp; + + temp = ohci_readl (controller, ®s->revision) & 0xff; + ohci_dbg_sw (controller, next, size, + "OHCI %d.%d, %s legacy support registers, rh state %s\n", + 0x03 & (temp >> 4), (temp & 0x0f), + (temp & 0x0100) ? "with" : "NO", + rh_state_string(controller)); + + temp = ohci_readl (controller, ®s->control); + ohci_dbg_sw (controller, next, size, + "control 0x%03x%s%s%s HCFS=%s%s%s%s%s CBSR=%d\n", + temp, + (temp & OHCI_CTRL_RWE) ? " RWE" : "", + (temp & OHCI_CTRL_RWC) ? " RWC" : "", + (temp & OHCI_CTRL_IR) ? " IR" : "", + hcfs2string (temp & OHCI_CTRL_HCFS), + (temp & OHCI_CTRL_BLE) ? " BLE" : "", + (temp & OHCI_CTRL_CLE) ? " CLE" : "", + (temp & OHCI_CTRL_IE) ? " IE" : "", + (temp & OHCI_CTRL_PLE) ? " PLE" : "", + temp & OHCI_CTRL_CBSR + ); + + temp = ohci_readl (controller, ®s->cmdstatus); + ohci_dbg_sw (controller, next, size, + "cmdstatus 0x%05x SOC=%d%s%s%s%s\n", temp, + (temp & OHCI_SOC) >> 16, + (temp & OHCI_OCR) ? " OCR" : "", + (temp & OHCI_BLF) ? " BLF" : "", + (temp & OHCI_CLF) ? " CLF" : "", + (temp & OHCI_HCR) ? " HCR" : "" + ); + + ohci_dump_intr_mask (controller, "intrstatus", + ohci_readl (controller, ®s->intrstatus), + next, size); + ohci_dump_intr_mask (controller, "intrenable", + ohci_readl (controller, ®s->intrenable), + next, size); + // intrdisable always same as intrenable + + maybe_print_eds (controller, "ed_periodcurrent", + ohci_readl (controller, ®s->ed_periodcurrent), + next, size); + + maybe_print_eds (controller, "ed_controlhead", + ohci_readl (controller, ®s->ed_controlhead), + next, size); + maybe_print_eds (controller, "ed_controlcurrent", + ohci_readl (controller, ®s->ed_controlcurrent), + next, size); + + maybe_print_eds (controller, "ed_bulkhead", + ohci_readl (controller, ®s->ed_bulkhead), + next, size); + maybe_print_eds (controller, "ed_bulkcurrent", + ohci_readl (controller, ®s->ed_bulkcurrent), + next, size); + + maybe_print_eds (controller, "donehead", + ohci_readl (controller, ®s->donehead), next, size); +} + +#define dbg_port_sw(hc,num,value,next,size) \ + ohci_dbg_sw (hc, next, size, \ + "roothub.portstatus [%d] " \ + "0x%08x%s%s%s%s%s%s%s%s%s%s%s%s\n", \ + num, temp, \ + (temp & RH_PS_PRSC) ? " PRSC" : "", \ + (temp & RH_PS_OCIC) ? " OCIC" : "", \ + (temp & RH_PS_PSSC) ? " PSSC" : "", \ + (temp & RH_PS_PESC) ? " PESC" : "", \ + (temp & RH_PS_CSC) ? " CSC" : "", \ + \ + (temp & RH_PS_LSDA) ? " LSDA" : "", \ + (temp & RH_PS_PPS) ? " PPS" : "", \ + (temp & RH_PS_PRS) ? " PRS" : "", \ + (temp & RH_PS_POCI) ? " POCI" : "", \ + (temp & RH_PS_PSS) ? " PSS" : "", \ + \ + (temp & RH_PS_PES) ? " PES" : "", \ + (temp & RH_PS_CCS) ? " CCS" : "" \ + ); + + +static void +ohci_dump_roothub ( + struct ohci_hcd *controller, + int verbose, + char **next, + unsigned *size) +{ + u32 temp, i; + + temp = roothub_a (controller); + if (temp == ~(u32)0) + return; + + if (verbose) { + ohci_dbg_sw (controller, next, size, + "roothub.a %08x POTPGT=%d%s%s%s%s%s NDP=%d(%d)\n", temp, + ((temp & RH_A_POTPGT) >> 24) & 0xff, + (temp & RH_A_NOCP) ? " NOCP" : "", + (temp & RH_A_OCPM) ? " OCPM" : "", + (temp & RH_A_DT) ? " DT" : "", + (temp & RH_A_NPS) ? " NPS" : "", + (temp & RH_A_PSM) ? " PSM" : "", + (temp & RH_A_NDP), controller->num_ports + ); + temp = roothub_b (controller); + ohci_dbg_sw (controller, next, size, + "roothub.b %08x PPCM=%04x DR=%04x\n", + temp, + (temp & RH_B_PPCM) >> 16, + (temp & RH_B_DR) + ); + temp = roothub_status (controller); + ohci_dbg_sw (controller, next, size, + "roothub.status %08x%s%s%s%s%s%s\n", + temp, + (temp & RH_HS_CRWE) ? " CRWE" : "", + (temp & RH_HS_OCIC) ? " OCIC" : "", + (temp & RH_HS_LPSC) ? " LPSC" : "", + (temp & RH_HS_DRWE) ? " DRWE" : "", + (temp & RH_HS_OCI) ? " OCI" : "", + (temp & RH_HS_LPS) ? " LPS" : "" + ); + } + + for (i = 0; i < controller->num_ports; i++) { + temp = roothub_portstatus (controller, i); + dbg_port_sw (controller, i, temp, next, size); + } +} + +static void ohci_dump(struct ohci_hcd *controller) +{ + ohci_dbg (controller, "OHCI controller state\n"); + + // dumps some of the state we know about + ohci_dump_status (controller, NULL, NULL); + if (controller->hcca) + ohci_dbg (controller, + "hcca frame #%04x\n", ohci_frame_no(controller)); + ohci_dump_roothub (controller, 1, NULL, NULL); +} + +static const char data0 [] = "DATA0"; +static const char data1 [] = "DATA1"; + +static void ohci_dump_td (const struct ohci_hcd *ohci, const char *label, + const struct td *td) +{ + u32 tmp = hc32_to_cpup (ohci, &td->hwINFO); + + ohci_dbg (ohci, "%s td %p%s; urb %p index %d; hw next td %08x\n", + label, td, + (tmp & TD_DONE) ? " (DONE)" : "", + td->urb, td->index, + hc32_to_cpup (ohci, &td->hwNextTD)); + if ((tmp & TD_ISO) == 0) { + const char *toggle, *pid; + u32 cbp, be; + + switch (tmp & TD_T) { + case TD_T_DATA0: toggle = data0; break; + case TD_T_DATA1: toggle = data1; break; + case TD_T_TOGGLE: toggle = "(CARRY)"; break; + default: toggle = "(?)"; break; + } + switch (tmp & TD_DP) { + case TD_DP_SETUP: pid = "SETUP"; break; + case TD_DP_IN: pid = "IN"; break; + case TD_DP_OUT: pid = "OUT"; break; + default: pid = "(bad pid)"; break; + } + ohci_dbg (ohci, " info %08x CC=%x %s DI=%d %s %s\n", tmp, + TD_CC_GET(tmp), /* EC, */ toggle, + (tmp & TD_DI) >> 21, pid, + (tmp & TD_R) ? "R" : ""); + cbp = hc32_to_cpup (ohci, &td->hwCBP); + be = hc32_to_cpup (ohci, &td->hwBE); + ohci_dbg (ohci, " cbp %08x be %08x (len %d)\n", cbp, be, + cbp ? (be + 1 - cbp) : 0); + } else { + unsigned i; + ohci_dbg (ohci, " info %08x CC=%x FC=%d DI=%d SF=%04x\n", tmp, + TD_CC_GET(tmp), + (tmp >> 24) & 0x07, + (tmp & TD_DI) >> 21, + tmp & 0x0000ffff); + ohci_dbg (ohci, " bp0 %08x be %08x\n", + hc32_to_cpup (ohci, &td->hwCBP) & ~0x0fff, + hc32_to_cpup (ohci, &td->hwBE)); + for (i = 0; i < MAXPSW; i++) { + u16 psw = ohci_hwPSW (ohci, td, i); + int cc = (psw >> 12) & 0x0f; + ohci_dbg (ohci, " psw [%d] = %2x, CC=%x %s=%d\n", i, + psw, cc, + (cc >= 0x0e) ? "OFFSET" : "SIZE", + psw & 0x0fff); + } + } +} + +/* caller MUST own hcd spinlock if verbose is set! */ +static void __maybe_unused +ohci_dump_ed (const struct ohci_hcd *ohci, const char *label, + const struct ed *ed, int verbose) +{ + u32 tmp = hc32_to_cpu (ohci, ed->hwINFO); + char *type = ""; + + ohci_dbg (ohci, "%s, ed %p state 0x%x type %s; next ed %08x\n", + label, + ed, ed->state, edstring (ed->type), + hc32_to_cpup (ohci, &ed->hwNextED)); + switch (tmp & (ED_IN|ED_OUT)) { + case ED_OUT: type = "-OUT"; break; + case ED_IN: type = "-IN"; break; + /* else from TDs ... control */ + } + ohci_dbg (ohci, + " info %08x MAX=%d%s%s%s%s EP=%d%s DEV=%d\n", tmp, + 0x03ff & (tmp >> 16), + (tmp & ED_DEQUEUE) ? " DQ" : "", + (tmp & ED_ISO) ? " ISO" : "", + (tmp & ED_SKIP) ? " SKIP" : "", + (tmp & ED_LOWSPEED) ? " LOW" : "", + 0x000f & (tmp >> 7), + type, + 0x007f & tmp); + tmp = hc32_to_cpup (ohci, &ed->hwHeadP); + ohci_dbg (ohci, " tds: head %08x %s%s tail %08x%s\n", + tmp, + (tmp & ED_C) ? data1 : data0, + (tmp & ED_H) ? " HALT" : "", + hc32_to_cpup (ohci, &ed->hwTailP), + verbose ? "" : " (not listing)"); + if (verbose) { + struct list_head *tmp; + + /* use ed->td_list because HC concurrently modifies + * hwNextTD as it accumulates ed_donelist. + */ + list_for_each (tmp, &ed->td_list) { + struct td *td; + td = list_entry (tmp, struct td, td_list); + ohci_dump_td (ohci, " ->", td); + } + } +} + +/*-------------------------------------------------------------------------*/ + +static int debug_async_open(struct inode *, struct file *); +static int debug_periodic_open(struct inode *, struct file *); +static int debug_registers_open(struct inode *, struct file *); +static int debug_async_open(struct inode *, struct file *); +static ssize_t debug_output(struct file*, char __user*, size_t, loff_t*); +static int debug_close(struct inode *, struct file *); + +static const struct file_operations debug_async_fops = { + .owner = THIS_MODULE, + .open = debug_async_open, + .read = debug_output, + .release = debug_close, + .llseek = default_llseek, +}; +static const struct file_operations debug_periodic_fops = { + .owner = THIS_MODULE, + .open = debug_periodic_open, + .read = debug_output, + .release = debug_close, + .llseek = default_llseek, +}; +static const struct file_operations debug_registers_fops = { + .owner = THIS_MODULE, + .open = debug_registers_open, + .read = debug_output, + .release = debug_close, + .llseek = default_llseek, +}; + +static struct dentry *ohci_debug_root; + +struct debug_buffer { + ssize_t (*fill_func)(struct debug_buffer *); /* fill method */ + struct ohci_hcd *ohci; + struct mutex mutex; /* protect filling of buffer */ + size_t count; /* number of characters filled into buffer */ + char *page; +}; + +static ssize_t +show_list (struct ohci_hcd *ohci, char *buf, size_t count, struct ed *ed) +{ + unsigned temp, size = count; + + if (!ed) + return 0; + + /* print first --> last */ + while (ed->ed_prev) + ed = ed->ed_prev; + + /* dump a snapshot of the bulk or control schedule */ + while (ed) { + u32 info = hc32_to_cpu (ohci, ed->hwINFO); + u32 headp = hc32_to_cpu (ohci, ed->hwHeadP); + struct list_head *entry; + struct td *td; + + temp = scnprintf (buf, size, + "ed/%p %cs dev%d ep%d%s max %d %08x%s%s %s", + ed, + (info & ED_LOWSPEED) ? 'l' : 'f', + info & 0x7f, + (info >> 7) & 0xf, + (info & ED_IN) ? "in" : "out", + 0x03ff & (info >> 16), + info, + (info & ED_SKIP) ? " s" : "", + (headp & ED_H) ? " H" : "", + (headp & ED_C) ? data1 : data0); + size -= temp; + buf += temp; + + list_for_each (entry, &ed->td_list) { + u32 cbp, be; + + td = list_entry (entry, struct td, td_list); + info = hc32_to_cpup (ohci, &td->hwINFO); + cbp = hc32_to_cpup (ohci, &td->hwCBP); + be = hc32_to_cpup (ohci, &td->hwBE); + temp = scnprintf (buf, size, + "\n\ttd %p %s %d cc=%x urb %p (%08x)", + td, + ({ char *pid; + switch (info & TD_DP) { + case TD_DP_SETUP: pid = "setup"; break; + case TD_DP_IN: pid = "in"; break; + case TD_DP_OUT: pid = "out"; break; + default: pid = "(?)"; break; + } pid;}), + cbp ? (be + 1 - cbp) : 0, + TD_CC_GET (info), td->urb, info); + size -= temp; + buf += temp; + } + + temp = scnprintf (buf, size, "\n"); + size -= temp; + buf += temp; + + ed = ed->ed_next; + } + return count - size; +} + +static ssize_t fill_async_buffer(struct debug_buffer *buf) +{ + struct ohci_hcd *ohci; + size_t temp, size; + unsigned long flags; + + ohci = buf->ohci; + size = PAGE_SIZE; + + /* display control and bulk lists together, for simplicity */ + spin_lock_irqsave (&ohci->lock, flags); + temp = show_list(ohci, buf->page, size, ohci->ed_controltail); + temp += show_list(ohci, buf->page + temp, size - temp, + ohci->ed_bulktail); + spin_unlock_irqrestore (&ohci->lock, flags); + + return temp; +} + +#define DBG_SCHED_LIMIT 64 + +static ssize_t fill_periodic_buffer(struct debug_buffer *buf) +{ + struct ohci_hcd *ohci; + struct ed **seen, *ed; + unsigned long flags; + unsigned temp, size, seen_count; + char *next; + unsigned i; + + seen = kmalloc_array(DBG_SCHED_LIMIT, sizeof(*seen), GFP_ATOMIC); + if (!seen) + return 0; + seen_count = 0; + + ohci = buf->ohci; + next = buf->page; + size = PAGE_SIZE; + + temp = scnprintf (next, size, "size = %d\n", NUM_INTS); + size -= temp; + next += temp; + + /* dump a snapshot of the periodic schedule (and load) */ + spin_lock_irqsave (&ohci->lock, flags); + for (i = 0; i < NUM_INTS; i++) { + ed = ohci->periodic[i]; + if (!ed) + continue; + + temp = scnprintf (next, size, "%2d [%3d]:", i, ohci->load [i]); + size -= temp; + next += temp; + + do { + temp = scnprintf (next, size, " ed%d/%p", + ed->interval, ed); + size -= temp; + next += temp; + for (temp = 0; temp < seen_count; temp++) { + if (seen [temp] == ed) + break; + } + + /* show more info the first time around */ + if (temp == seen_count) { + u32 info = hc32_to_cpu (ohci, ed->hwINFO); + struct list_head *entry; + unsigned qlen = 0; + + /* qlen measured here in TDs, not urbs */ + list_for_each (entry, &ed->td_list) + qlen++; + + temp = scnprintf (next, size, + " (%cs dev%d ep%d%s-%s qlen %u" + " max %d %08x%s%s)", + (info & ED_LOWSPEED) ? 'l' : 'f', + info & 0x7f, + (info >> 7) & 0xf, + (info & ED_IN) ? "in" : "out", + (info & ED_ISO) ? "iso" : "int", + qlen, + 0x03ff & (info >> 16), + info, + (info & ED_SKIP) ? " K" : "", + (ed->hwHeadP & + cpu_to_hc32(ohci, ED_H)) ? + " H" : ""); + size -= temp; + next += temp; + + if (seen_count < DBG_SCHED_LIMIT) + seen [seen_count++] = ed; + + ed = ed->ed_next; + + } else { + /* we've seen it and what's after */ + temp = 0; + ed = NULL; + } + + } while (ed); + + temp = scnprintf (next, size, "\n"); + size -= temp; + next += temp; + } + spin_unlock_irqrestore (&ohci->lock, flags); + kfree (seen); + + return PAGE_SIZE - size; +} +#undef DBG_SCHED_LIMIT + +static ssize_t fill_registers_buffer(struct debug_buffer *buf) +{ + struct usb_hcd *hcd; + struct ohci_hcd *ohci; + struct ohci_regs __iomem *regs; + unsigned long flags; + unsigned temp, size; + char *next; + u32 rdata; + + ohci = buf->ohci; + hcd = ohci_to_hcd(ohci); + regs = ohci->regs; + next = buf->page; + size = PAGE_SIZE; + + spin_lock_irqsave (&ohci->lock, flags); + + /* dump driver info, then registers in spec order */ + + ohci_dbg_nosw(ohci, &next, &size, + "bus %s, device %s\n" + "%s\n" + "%s\n", + hcd->self.controller->bus->name, + dev_name(hcd->self.controller), + hcd->product_desc, + hcd_name); + + if (!HCD_HW_ACCESSIBLE(hcd)) { + size -= scnprintf (next, size, + "SUSPENDED (no register access)\n"); + goto done; + } + + ohci_dump_status(ohci, &next, &size); + + /* hcca */ + if (ohci->hcca) + ohci_dbg_nosw(ohci, &next, &size, + "hcca frame 0x%04x\n", ohci_frame_no(ohci)); + + /* other registers mostly affect frame timings */ + rdata = ohci_readl (ohci, ®s->fminterval); + temp = scnprintf (next, size, + "fmintvl 0x%08x %sFSMPS=0x%04x FI=0x%04x\n", + rdata, (rdata >> 31) ? "FIT " : "", + (rdata >> 16) & 0xefff, rdata & 0xffff); + size -= temp; + next += temp; + + rdata = ohci_readl (ohci, ®s->fmremaining); + temp = scnprintf (next, size, "fmremaining 0x%08x %sFR=0x%04x\n", + rdata, (rdata >> 31) ? "FRT " : "", + rdata & 0x3fff); + size -= temp; + next += temp; + + rdata = ohci_readl (ohci, ®s->periodicstart); + temp = scnprintf (next, size, "periodicstart 0x%04x\n", + rdata & 0x3fff); + size -= temp; + next += temp; + + rdata = ohci_readl (ohci, ®s->lsthresh); + temp = scnprintf (next, size, "lsthresh 0x%04x\n", + rdata & 0x3fff); + size -= temp; + next += temp; + + temp = scnprintf (next, size, "hub poll timer %s\n", + HCD_POLL_RH(ohci_to_hcd(ohci)) ? "ON" : "off"); + size -= temp; + next += temp; + + /* roothub */ + ohci_dump_roothub (ohci, 1, &next, &size); + +done: + spin_unlock_irqrestore (&ohci->lock, flags); + + return PAGE_SIZE - size; +} + +static struct debug_buffer *alloc_buffer(struct ohci_hcd *ohci, + ssize_t (*fill_func)(struct debug_buffer *)) +{ + struct debug_buffer *buf; + + buf = kzalloc(sizeof(struct debug_buffer), GFP_KERNEL); + + if (buf) { + buf->ohci = ohci; + buf->fill_func = fill_func; + mutex_init(&buf->mutex); + } + + return buf; +} + +static int fill_buffer(struct debug_buffer *buf) +{ + int ret; + + if (!buf->page) + buf->page = (char *)get_zeroed_page(GFP_KERNEL); + + if (!buf->page) { + ret = -ENOMEM; + goto out; + } + + ret = buf->fill_func(buf); + + if (ret >= 0) { + buf->count = ret; + ret = 0; + } + +out: + return ret; +} + +static ssize_t debug_output(struct file *file, char __user *user_buf, + size_t len, loff_t *offset) +{ + struct debug_buffer *buf = file->private_data; + int ret; + + mutex_lock(&buf->mutex); + if (buf->count == 0) { + ret = fill_buffer(buf); + if (ret != 0) { + mutex_unlock(&buf->mutex); + goto out; + } + } + mutex_unlock(&buf->mutex); + + ret = simple_read_from_buffer(user_buf, len, offset, + buf->page, buf->count); + +out: + return ret; + +} + +static int debug_close(struct inode *inode, struct file *file) +{ + struct debug_buffer *buf = file->private_data; + + if (buf) { + if (buf->page) + free_page((unsigned long)buf->page); + kfree(buf); + } + + return 0; +} +static int debug_async_open(struct inode *inode, struct file *file) +{ + file->private_data = alloc_buffer(inode->i_private, fill_async_buffer); + + return file->private_data ? 0 : -ENOMEM; +} + +static int debug_periodic_open(struct inode *inode, struct file *file) +{ + file->private_data = alloc_buffer(inode->i_private, + fill_periodic_buffer); + + return file->private_data ? 0 : -ENOMEM; +} + +static int debug_registers_open(struct inode *inode, struct file *file) +{ + file->private_data = alloc_buffer(inode->i_private, + fill_registers_buffer); + + return file->private_data ? 0 : -ENOMEM; +} +static inline void create_debug_files (struct ohci_hcd *ohci) +{ + struct usb_bus *bus = &ohci_to_hcd(ohci)->self; + struct dentry *root; + + root = debugfs_create_dir(bus->bus_name, ohci_debug_root); + ohci->debug_dir = root; + + debugfs_create_file("async", S_IRUGO, root, ohci, &debug_async_fops); + debugfs_create_file("periodic", S_IRUGO, root, ohci, + &debug_periodic_fops); + debugfs_create_file("registers", S_IRUGO, root, ohci, + &debug_registers_fops); + + ohci_dbg (ohci, "created debug files\n"); +} + +static inline void remove_debug_files (struct ohci_hcd *ohci) +{ + debugfs_remove_recursive(ohci->debug_dir); +} + +/*-------------------------------------------------------------------------*/ + |