diff options
author | Philippe De Muyter <phdm@macqel.be> | 2009-02-19 01:48:36 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-02-19 02:37:55 +0300 |
commit | 5a74db06cc8d36a325913aa4968ae169f997a466 (patch) | |
tree | 68eb369ba49b4c764d4900ae41b5115c615a8a83 /drivers/block/floppy.c | |
parent | ffa7525c13eb3db0fd19a3e1cffe2ce6f561f5f3 (diff) | |
download | linux-5a74db06cc8d36a325913aa4968ae169f997a466.tar.xz |
floppy: request and release only the ports we actually use
The floppy driver requests an I/O port it doesn't need, and sometimes this
causes a conflict with a motherboard device reported by PNPBIOS.
This patch makes the floppy driver request and release only the ports it
actually uses. It also factors out the request/release stuff and the
io-ports list so they're all in one place now.
The current floppy driver uses only these ports:
0x3f2 (FD_DOR)
0x3f4 (FD_STATUS)
0x3f5 (FD_DATA)
0x3f7 (FD_DCR/FD_DIR)
but it requests 0x3f2-0x3f5 and 0x3f7, which includes the unused port
0x3f3.
Some BIOSes report 0x3f3 as a motherboard resource. The PNP system driver
reserves that, which causes a conflict when the floppy driver requests
0x3f2-0x3f5 later.
Philippe reported that this conflict broke the floppy driver between
2.6.11 and 2.6.22. His PNPBIOS reports these devices:
$ cat 00:07/id 00:07/resources # motherboard device
PNP0c02
state = active
io 0x80-0x80
io 0x10-0x1f
io 0x22-0x3f
io 0x44-0x5f
io 0x90-0x9f
io 0xa2-0xbf
io 0x3f0-0x3f1
io 0x3f3-0x3f3
$ cat 00:03/id 00:03/resources # floppy device
PNP0700
state = active
io 0x3f4-0x3f5
io 0x3f2-0x3f2
Reference:
http://lkml.org/lkml/2009/1/31/162
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Philippe De Muyter <phdm@macqel.be>
Reported-by: Philippe De Muyter <phdm@macqel.be>
Tested-by: Philippe De Muyter <phdm@macqel.be>
Cc: Adam M Belay <abelay@mit.edu>
Cc: Robert Hancock <hancockrwd@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/block/floppy.c')
-rw-r--r-- | drivers/block/floppy.c | 79 |
1 files changed, 52 insertions, 27 deletions
diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c index cf29cc4e6ab7..83d8ed39433d 100644 --- a/drivers/block/floppy.c +++ b/drivers/block/floppy.c @@ -558,6 +558,8 @@ static void process_fd_request(void); static void recalibrate_floppy(void); static void floppy_shutdown(unsigned long); +static int floppy_request_regions(int); +static void floppy_release_regions(int); static int floppy_grab_irq_and_dma(void); static void floppy_release_irq_and_dma(void); @@ -4274,8 +4276,7 @@ static int __init floppy_init(void) FDCS->rawcmd = 2; if (user_reset_fdc(-1, FD_RESET_ALWAYS, 0)) { /* free ioports reserved by floppy_grab_irq_and_dma() */ - release_region(FDCS->address + 2, 4); - release_region(FDCS->address + 7, 1); + floppy_release_regions(fdc); FDCS->address = -1; FDCS->version = FDC_NONE; continue; @@ -4284,8 +4285,7 @@ static int __init floppy_init(void) FDCS->version = get_fdc_version(); if (FDCS->version == FDC_NONE) { /* free ioports reserved by floppy_grab_irq_and_dma() */ - release_region(FDCS->address + 2, 4); - release_region(FDCS->address + 7, 1); + floppy_release_regions(fdc); FDCS->address = -1; continue; } @@ -4358,6 +4358,47 @@ out_put_disk: static DEFINE_SPINLOCK(floppy_usage_lock); +static const struct io_region { + int offset; + int size; +} io_regions[] = { + { 2, 1 }, + /* address + 3 is sometimes reserved by pnp bios for motherboard */ + { 4, 2 }, + /* address + 6 is reserved, and may be taken by IDE. + * Unfortunately, Adaptec doesn't know this :-(, */ + { 7, 1 }, +}; + +static void floppy_release_allocated_regions(int fdc, const struct io_region *p) +{ + while (p != io_regions) { + p--; + release_region(FDCS->address + p->offset, p->size); + } +} + +#define ARRAY_END(X) (&((X)[ARRAY_SIZE(X)])) + +static int floppy_request_regions(int fdc) +{ + const struct io_region *p; + + for (p = io_regions; p < ARRAY_END(io_regions); p++) { + if (!request_region(FDCS->address + p->offset, p->size, "floppy")) { + DPRINT("Floppy io-port 0x%04lx in use\n", FDCS->address + p->offset); + floppy_release_allocated_regions(fdc, p); + return -EBUSY; + } + } + return 0; +} + +static void floppy_release_regions(int fdc) +{ + floppy_release_allocated_regions(fdc, ARRAY_END(io_regions)); +} + static int floppy_grab_irq_and_dma(void) { unsigned long flags; @@ -4399,18 +4440,8 @@ static int floppy_grab_irq_and_dma(void) for (fdc = 0; fdc < N_FDC; fdc++) { if (FDCS->address != -1) { - if (!request_region(FDCS->address + 2, 4, "floppy")) { - DPRINT("Floppy io-port 0x%04lx in use\n", - FDCS->address + 2); - goto cleanup1; - } - if (!request_region(FDCS->address + 7, 1, "floppy DIR")) { - DPRINT("Floppy io-port 0x%04lx in use\n", - FDCS->address + 7); - goto cleanup2; - } - /* address + 6 is reserved, and may be taken by IDE. - * Unfortunately, Adaptec doesn't know this :-(, */ + if (floppy_request_regions(fdc)) + goto cleanup; } } for (fdc = 0; fdc < N_FDC; fdc++) { @@ -4432,15 +4463,11 @@ static int floppy_grab_irq_and_dma(void) fdc = 0; irqdma_allocated = 1; return 0; -cleanup2: - release_region(FDCS->address + 2, 4); -cleanup1: +cleanup: fd_free_irq(); fd_free_dma(); - while (--fdc >= 0) { - release_region(FDCS->address + 2, 4); - release_region(FDCS->address + 7, 1); - } + while (--fdc >= 0) + floppy_release_regions(fdc); spin_lock_irqsave(&floppy_usage_lock, flags); usage_count--; spin_unlock_irqrestore(&floppy_usage_lock, flags); @@ -4501,10 +4528,8 @@ static void floppy_release_irq_and_dma(void) #endif old_fdc = fdc; for (fdc = 0; fdc < N_FDC; fdc++) - if (FDCS->address != -1) { - release_region(FDCS->address + 2, 4); - release_region(FDCS->address + 7, 1); - } + if (FDCS->address != -1) + floppy_release_regions(fdc); fdc = old_fdc; } |