From 4112e16a7c606a80810d22d55bfc742eaa61fecb Mon Sep 17 00:00:00 2001 From: Alan Date: Mon, 8 Jan 2007 12:10:05 +0000 Subject: [PATCH] libata-sff: Don't try and activate channels which are not in use An ATA controller in native mode may have one or more channels disabled and not assigned resources. In that case the existing code crashes trying to access I/O ports 0-7. Add the neccessary check. Signed-off-by: Alan Cox Signed-off-by: Jeff Garzik --- drivers/ata/libata-sff.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c index 12c88c5..cfa9ed179 100644 --- a/drivers/ata/libata-sff.c +++ b/drivers/ata/libata-sff.c @@ -832,6 +832,21 @@ void ata_bmdma_post_internal_cmd(struct ata_queued_cmd *qc) } #ifdef CONFIG_PCI + +static int ata_resources_present(struct pci_dev *pdev, int port) +{ + int i; + + /* Check the PCI resources for this channel are enabled */ + port = port * 2; + for (i = 0; i < 2; i ++) { + if (pci_resource_start(pdev, port + i) == 0 || + pci_resource_len(pdev, port + i) == 0) + return 0; + } + return 1; +} + /** * ata_pci_init_native_mode - Initialize native-mode driver * @pdev: pci device to be initialized @@ -863,6 +878,13 @@ ata_pci_init_native_mode(struct pci_dev *pdev, struct ata_port_info **port, int probe_ent->irq = pdev->irq; probe_ent->irq_flags = IRQF_SHARED; + + /* Discard disabled ports. Some controllers show their + unused channels this way */ + if (ata_resources_present(pdev, 0) == 0) + ports &= ~ATA_PORT_PRIMARY; + if (ata_resources_present(pdev, 1) == 0) + ports &= ~ATA_PORT_SECONDARY; if (ports & ATA_PORT_PRIMARY) { probe_ent->port[p].cmd_addr = pci_resource_start(pdev, 0); -- 2.7.4