Messages in this thread Patch in this message | | | Date | Fri, 30 May 2008 23:15:57 +0200 | From | Rene Herman <> | Subject | [PATCH] Re: 2.6.26-rc1 regression: ISA DMA broken (bisected) |
| |
On 14-05-08 21:09, Rene Herman wrote:
> On 14-05-08 20:50, Bjorn Helgaas wrote:
>> I agree, it seems a bit of a hack to use a DMA mask from the card >> instead of from the device, since the driver should be programming >> the device to do the DMA. >> >> But I know very little about pnp_card in general, so don't attach too >> much weight to my opinion. > > Okay, I'll sit on this for a bit. Right now we're using a global device > even but this is exactly about cleaning that up so couldn't convince > myself. Will see what happens when I try to make it nice...
It gets uglier. ALSA ISA drivers (for cards that exist both as legacy and as ISAPnP at least) keep a merged legacy/isapnp model; PnP is used mostly for initializing global variables that the same old legacy probe routines then reference. This means that beyond that global resource init step the specific struct device is no longer available. Without restructuring too many things really only fixable through other hacks again such as a global dma_dev[] array or some such.
From the viewpoint of PnP itself setting the dma_mask for a pnp_card (a pnp_dev collection) makes isolated sense so if no objections, I'll submit the attached after all. From the ALSA side we'd then pass the card dev (which we'd also do for isa_dev) and keep in mind that we might want to get more specific if over time structure permits it.
struct snd_pcm already has its own struct device * which would be the right one here but it's setting that which gets ugly...
Rene. From b4e8e6b833d2e8ed3a2b78912c4afff563d8ae21 Mon Sep 17 00:00:00 2001 From: Rene Herman <rene.herman@gmail.com> Date: Fri, 30 May 2008 23:10:23 +0200 Subject: [PATCH] PNP: set the pnp_card dma_mask for use by ISAPnP cards.
This makes the pnp_card->dev available as a DMAable device same as the pnp_dev->dev.
Signed-off-by: Rene Herman <rene.herman@gmail.com> --- drivers/pnp/card.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-)
diff --git a/drivers/pnp/card.c b/drivers/pnp/card.c index a762a41..b00ef10 100644 --- a/drivers/pnp/card.c +++ b/drivers/pnp/card.c @@ -8,6 +8,7 @@ #include <linux/ctype.h> #include <linux/slab.h> #include <linux/pnp.h> +#include <linux/dma-mapping.h> #include "base.h" LIST_HEAD(pnp_cards); @@ -167,6 +168,9 @@ struct pnp_card *pnp_alloc_card(struct pnp_protocol *protocol, int id, char *pnp sprintf(card->dev.bus_id, "%02x:%02x", card->protocol->number, card->number); + card->dev.coherent_dma_mask = DMA_24BIT_MASK; + card->dev.dma_mask = &card->dev.coherent_dma_mask; + dev_id = pnp_add_card_id(card, pnpid); if (!dev_id) { kfree(card); -- 1.5.2.2
| |