For many cards, this saves some IO space because interrupt status port has precedence over the rest of ports on the card. Hence it can be mapped to a hole in I/O ports.
Here we add a kernel parameter which allows that if a user wants to. But they need to explicitly enable it by a module parameter. Signed-off-by: Jiri Slaby <[email protected]> --- drivers/tty/mxser.c | 35 +++++++++++++++++++++++++++++++---- 1 file changed, 31 insertions(+), 4 deletions(-) diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c index c162ee9..e64fe40 100644 --- a/drivers/tty/mxser.c +++ b/drivers/tty/mxser.c @@ -2337,11 +2337,36 @@ static struct tty_port_operations mxser_port_ops = { * The MOXA Smartio/Industio serial driver boot-time initialization code! */ +static bool allow_overlapping_vector; +module_param(allow_overlapping_vector, bool, 444); +MODULE_PARM_DESC(allow_overlapping_vector, "whether we allow ISA cards to be configured such that vector overlabs IO ports (default=no)"); + +static bool mxser_overlapping_vector(struct mxser_board *brd) +{ + return allow_overlapping_vector && + brd->vector >= brd->ports[0].ioaddr && + brd->vector < brd->ports[0].ioaddr + 8 * brd->info->nports; +} + +static int mxser_request_vector(struct mxser_board *brd) +{ + if (mxser_overlapping_vector(brd)) + return 0; + return request_region(brd->vector, 1, "mxser(vector)") ? 0 : -EIO; +} + +static void mxser_release_vector(struct mxser_board *brd) +{ + if (mxser_overlapping_vector(brd)) + return; + release_region(brd->vector, 1); +} + static void mxser_release_ISA_res(struct mxser_board *brd) { free_irq(brd->irq, brd); release_region(brd->ports[0].ioaddr, 8 * brd->info->nports); - release_region(brd->vector, 1); + mxser_release_vector(brd); } static int __devinit mxser_initbrd(struct mxser_board *brd, @@ -2396,7 +2421,7 @@ static int __devinit mxser_initbrd(struct mxser_board *brd, static int __init mxser_get_ISA_conf(int cap, struct mxser_board *brd) { - int id, i, bits; + int id, i, bits, ret; unsigned short regs[16], irq; unsigned char scratch, scratch2; @@ -2492,13 +2517,15 @@ static int __init mxser_get_ISA_conf(int cap, struct mxser_board *brd) 8 * brd->info->nports - 1); return -EIO; } - if (!request_region(brd->vector, 1, "mxser(vector)")) { + + ret = mxser_request_vector(brd); + if (ret) { release_region(brd->ports[0].ioaddr, 8 * brd->info->nports); printk(KERN_ERR "mxser: can't request interrupt vector region: " "0x%.8lx-0x%.8lx\n", brd->ports[0].ioaddr, brd->ports[0].ioaddr + 8 * brd->info->nports - 1); - return -EIO; + return ret; } return brd->info->nports; -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
