[PATCH 1/6] pata_cypress: add a module option to disable BM-DMA
From: Christoph Hellwig <hch@lst.de>
Date: 2021-06-16 13:48:12
Also in:
linux-alpha, linux-arm-kernel, linux-ide, linux-m68k, lkml
Subsystem:
libata subsystem (serial and parallel ata drivers), the rest · Maintainers:
Damien Le Moal, Niklas Cassel, Linus Torvalds
Multiple users report that they need to disable DMA on this driver, so provide an option to do so without affecting all of libata. Signed-off-by: Christoph Hellwig <hch@lst.de> --- drivers/ata/pata_cypress.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/ata/pata_cypress.c b/drivers/ata/pata_cypress.c
index e1486fe298ae..5b3a7a8ebef6 100644
--- a/drivers/ata/pata_cypress.c
+++ b/drivers/ata/pata_cypress.c@@ -41,6 +41,10 @@ enum { CY82_INDEX_TIMEOUT = 0x32 }; +static bool enable_dma = true; +module_param(enable_dma, bool, 0); +MODULE_PARM_DESC(enable_dma, "Enable bus master DMA operations"); + /** * cy82c693_set_piomode - set initial PIO mode data * @ap: ATA interface
@@ -124,14 +128,16 @@ static struct ata_port_operations cy82c693_port_ops = { static int cy82c693_init_one(struct pci_dev *pdev, const struct pci_device_id *id) { - static const struct ata_port_info info = { + static struct ata_port_info info = { .flags = ATA_FLAG_SLAVE_POSS, .pio_mask = ATA_PIO4, - .mwdma_mask = ATA_MWDMA2, .port_ops = &cy82c693_port_ops }; const struct ata_port_info *ppi[] = { &info, &ata_dummy_port_info }; + if (enable_dma) + info.mwdma_mask = ATA_MWDMA2; + /* Devfn 1 is the ATA primary. The secondary is magic and on devfn2. For the moment we don't handle the secondary. FIXME */
--
2.30.2