Hi, On Tuesday, February 21, 2017 11:22:37 AM Luiz Carlos Ramos wrote: > Some inline comments were added in ide-generic, to make clear to > developers the way probe_mask is managed when PCI IDE devices are > present. > > A not-so-deep analysis of the code could make it is buggy, as it seems > that if a device is detected, the probing procedure is avoided, > suggesting some kind of reversed logic. > > Signed-off-by: Luiz Carlos Ramos <lramos.prof@xxxxxxxxxxxx> Looks fine overall, some minor nits below. > --- > drivers/ide/ide-generic.c | 27 +++++++++++++++++++++++++++ > 1 file changed, 27 insertions(+) > > diff --git a/drivers/ide/ide-generic.c b/drivers/ide/ide-generic.c > index 54d7c4685d23aa5e62ce606e7b994a57bb54b08a..ee11edcdba3170c077381d603918498d79ffa3bb 100644 > --- a/drivers/ide/ide-generic.c > +++ b/drivers/ide/ide-generic.c > @@ -96,6 +96,33 @@ static int __init ide_generic_init(void) > printk(KERN_INFO DRV_NAME ": please use \"probe_mask=0x3f\" " > "module parameter for probing all legacy ISA IDE ports\n"); > > + /* Here the logic seems reversed, but it's not. *primary would > + * be 1 if there is a device at 0x1f0 and *secondary would be 1 > + * if a device is detected at 0x170. > + * > + * However, the main intention here is to not allow PCI IDE devices > + * using ide-generic unless the user chooses so, as this driver is > + * designed to support ISA IDE devices mainly. designed to support legacy ISA IDE devices that don't have chipset specific support. > + * > + * In this case, users are strongly encouraged to use the designated > + * PCI IDE driver, and not isa-generic. PCI IDE drivers, and not ide-generic. > + * > + * Pure ISA IDE devices OTOH will use ide-generic. In this case, *primary > + * and *secondary will return from ide_generic_check_pci_legacy_iobases() > + * with zero (because they are not PCI...), and probe_mask will be set > + * accordingly (to 0x01, 0x02 or 0x03, depending on which io ports are > + * present). > + * > + * Users would even use ide-generic with such PCI IDE devices, choosing a Users who would like to use ide-generic with PCI IDE devices (which is not recommended) should choose a > + * nonzero value for probe_mask when initializing ide-generic. Using > + * probe_mask=0x03 is sufficient to make it detect common IDE interfaces > + * (with primary at 0x1f0 and secondary at 0x170), but in the more > + * general case, one should set probe_mask to 0x3f to check all possible > + * io addresses. In this case, it is up to the user the task of checking IO addresses. When using probe_mask it is up to the user to check > + * for eventual conflicts between ide-generic and any other driver and > + * manage those conflicts properly. > + */ > + > if (primary == 0) > probe_mask |= 0x1; Best regards, -- Bartlomiej Zolnierkiewicz Samsung R&D Institute Poland Samsung Electronics -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
