From stern@rowland.harvard.edu Sat Dec 17 15:14:04 2005 Date: Sat, 17 Dec 2005 18:03:37 -0500 (EST) From: Alan Stern To: Greg KH Subject: [PATCH 4/4] UHCI: improve debugging code Message-ID: This patch (as626) makes some improvements to the debugging code in uhci-hcd. The main change is that now the code won't get compiled if CONFIG_USB_DEBUG isn't set. But there are other changes too, like adding a missing .owner field and printing a debugging dump if the controller dies. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/uhci-debug.c | 36 ++++++++++++++++++++----- drivers/usb/host/uhci-hcd.c | 60 +++++++++++++++++++++++++++--------------- drivers/usb/host/uhci-hcd.h | 1 drivers/usb/host/uhci-q.c | 12 -------- 4 files changed, 70 insertions(+), 39 deletions(-) --- gregkh-2.6.orig/drivers/usb/host/uhci-q.c +++ gregkh-2.6/drivers/usb/host/uhci-q.c @@ -736,7 +736,6 @@ err: if (errbuf) { /* Print the chain for debugging purposes */ uhci_show_qh(urbp->qh, errbuf, ERRBUF_LEN, 0); - lprintk(errbuf); } } @@ -924,26 +923,17 @@ td_error: ret = uhci_map_status(status, uhci_packetout(td_token(td))); err: - /* - * Enable this chunk of code if you want to see some more debugging. - * But be careful, it has the tendancy to starve out khubd and prevent - * disconnects from happening successfully if you have a slow debug - * log interface (like a serial console. - */ -#if 0 if ((debug == 1 && ret != -EPIPE) || debug > 1) { /* Some debugging code */ dev_dbg(uhci_dev(uhci), "%s: failed with status %x\n", __FUNCTION__, status); - if (errbuf) { + if (debug > 1 && errbuf) { /* Print the chain for debugging purposes */ uhci_show_qh(urbp->qh, errbuf, ERRBUF_LEN, 0); - lprintk(errbuf); } } -#endif /* Note that the queue has stopped and save the next toggle value */ urbp->qh->element = UHCI_PTR_TERM; --- gregkh-2.6.orig/drivers/usb/host/uhci-hcd.c +++ gregkh-2.6/drivers/usb/host/uhci-hcd.c @@ -68,12 +68,16 @@ Alan Stern" * debug = 3, show all TDs in URBs when dumping */ #ifdef DEBUG +#define DEBUG_CONFIGURED 1 static int debug = 1; -#else -static int debug = 0; -#endif module_param(debug, int, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(debug, "Debug level"); + +#else +#define DEBUG_CONFIGURED 0 +#define debug 0 +#endif + static char *errbuf; #define ERRBUF_LEN (32 * 1024) @@ -338,6 +342,12 @@ static irqreturn_t uhci_irq(struct usb_h dev_err(uhci_dev(uhci), "host controller halted, " "very bad!\n"); + if (debug > 1 && errbuf) { + /* Print the schedule for debugging */ + uhci_sprint_schedule(uhci, + errbuf, ERRBUF_LEN); + lprintk(errbuf); + } hc_died(uhci); /* Force a callback in case there are @@ -376,6 +386,14 @@ static void release_uhci(struct uhci_hcd { int i; + if (DEBUG_CONFIGURED) { + spin_lock_irq(&uhci->lock); + uhci->is_initialized = 0; + spin_unlock_irq(&uhci->lock); + + debugfs_remove(uhci->dentry); + } + for (i = 0; i < UHCI_NUM_SKELQH; i++) uhci_free_qh(uhci, uhci->skelqh[i]); @@ -390,8 +408,6 @@ static void release_uhci(struct uhci_hcd dma_free_coherent(uhci_dev(uhci), UHCI_NUMFRAMES * sizeof(*uhci->frame), uhci->frame, uhci->frame_dma_handle); - - debugfs_remove(uhci->dentry); } static int uhci_reset(struct usb_hcd *hcd) @@ -474,17 +490,6 @@ static int uhci_start(struct usb_hcd *hc hcd->uses_new_polling = 1; - dentry = debugfs_create_file(hcd->self.bus_name, - S_IFREG|S_IRUGO|S_IWUSR, uhci_debugfs_root, uhci, - &uhci_debug_operations); - if (!dentry) { - dev_err(uhci_dev(uhci), - "couldn't create uhci debugfs entry\n"); - retval = -ENOMEM; - goto err_create_debug_entry; - } - uhci->dentry = dentry; - uhci->fsbr = 0; uhci->fsbrtimeout = 0; @@ -495,6 +500,19 @@ static int uhci_start(struct usb_hcd *hc init_waitqueue_head(&uhci->waitqh); + if (DEBUG_CONFIGURED) { + dentry = debugfs_create_file(hcd->self.bus_name, + S_IFREG|S_IRUGO|S_IWUSR, uhci_debugfs_root, + uhci, &uhci_debug_operations); + if (!dentry) { + dev_err(uhci_dev(uhci), "couldn't create uhci " + "debugfs entry\n"); + retval = -ENOMEM; + goto err_create_debug_entry; + } + uhci->dentry = dentry; + } + uhci->frame = dma_alloc_coherent(uhci_dev(uhci), UHCI_NUMFRAMES * sizeof(*uhci->frame), &uhci->frame_dma_handle, 0); @@ -609,6 +627,7 @@ static int uhci_start(struct usb_hcd *hc mb(); configure_hc(uhci); + uhci->is_initialized = 1; start_rh(uhci); return 0; @@ -872,16 +891,15 @@ static int __init uhci_hcd_init(void) if (usb_disabled()) return -ENODEV; - if (debug) { + if (DEBUG_CONFIGURED) { errbuf = kmalloc(ERRBUF_LEN, GFP_KERNEL); if (!errbuf) goto errbuf_failed; + uhci_debugfs_root = debugfs_create_dir("uhci", NULL); + if (!uhci_debugfs_root) + goto debug_failed; } - uhci_debugfs_root = debugfs_create_dir("uhci", NULL); - if (!uhci_debugfs_root) - goto debug_failed; - uhci_up_cachep = kmem_cache_create("uhci_urb_priv", sizeof(struct urb_priv), 0, 0, NULL, NULL); if (!uhci_up_cachep) --- gregkh-2.6.orig/drivers/usb/host/uhci-debug.c +++ gregkh-2.6/drivers/usb/host/uhci-debug.c @@ -17,10 +17,13 @@ #include "uhci-hcd.h" -static struct dentry *uhci_debugfs_root = NULL; +#define uhci_debug_operations (* (struct file_operations *) NULL) +static struct dentry *uhci_debugfs_root; + +#ifdef DEBUG /* Handle REALLY large printks so we don't overflow buffers */ -static inline void lprintk(char *buf) +static void lprintk(char *buf) { char *p; @@ -196,7 +199,6 @@ static int uhci_show_qh(struct uhci_qh * return out - buf; } -#ifdef CONFIG_PROC_FS static const char * const qh_names[] = { "skel_unlink_qh", "skel_iso_qh", "skel_int128_qh", "skel_int64_qh", @@ -393,12 +395,13 @@ static int uhci_sprint_schedule(struct u return out - buf; } +#ifdef CONFIG_DEBUG_FS + #define MAX_OUTPUT (64 * 1024) struct uhci_debug { int size; char *data; - struct uhci_hcd *uhci; }; static int uhci_debug_open(struct inode *inode, struct file *file) @@ -419,8 +422,10 @@ static int uhci_debug_open(struct inode goto out; } + up->size = 0; spin_lock_irqsave(&uhci->lock, flags); - up->size = uhci_sprint_schedule(uhci, up->data, MAX_OUTPUT); + if (uhci->is_initialized) + up->size = uhci_sprint_schedule(uhci, up->data, MAX_OUTPUT); spin_unlock_irqrestore(&uhci->lock, flags); file->private_data = up; @@ -472,15 +477,32 @@ static int uhci_debug_release(struct ino return 0; } +#undef uhci_debug_operations static struct file_operations uhci_debug_operations = { + .owner = THIS_MODULE, .open = uhci_debug_open, .llseek = uhci_debug_lseek, .read = uhci_debug_read, .release = uhci_debug_release, }; -#else /* CONFIG_DEBUG_FS */ +#endif /* CONFIG_DEBUG_FS */ -#define uhci_debug_operations (* (struct file_operations *) NULL) +#else /* DEBUG */ + +static inline void lprintk(char *buf) +{} + +static inline int uhci_show_qh(struct uhci_qh *qh, char *buf, + int len, int space) +{ + return 0; +} + +static inline int uhci_sprint_schedule(struct uhci_hcd *uhci, + char *buf, int len) +{ + return 0; +} #endif --- gregkh-2.6.orig/drivers/usb/host/uhci-hcd.h +++ gregkh-2.6/drivers/usb/host/uhci-hcd.h @@ -411,6 +411,7 @@ struct uhci_hcd { unsigned int hc_inaccessible:1; /* HC is suspended or dead */ unsigned int working_RD:1; /* Suspended root hub doesn't need to be polled */ + unsigned int is_initialized:1; /* Data structure is usable */ /* Support for port suspend/resume/reset */ unsigned long port_c_suspend; /* Bit-arrays of ports */