drivers/ata/pata_sch.c
Source file repositories/reference/linux-study-clean/drivers/ata/pata_sch.c
File Facts
- System
- Linux kernel
- Corpus path
drivers/ata/pata_sch.c- Extension
.c- Size
- 4542 bytes
- Lines
- 168
- Domain
- Driver Families
- Bucket
- drivers/ata
- Inferred role
- Driver Families: operation-table or driver-model contract
- Status
- pattern implementation candidate
Why This File Exists
Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Defines an operation table; this is where Linux turns generic core objects into subsystem-specific behavior.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/kernel.hlinux/module.hlinux/pci.hlinux/blkdev.hlinux/delay.hlinux/device.hscsi/scsi_host.hlinux/libata.hlinux/dmi.h
Detected Declarations
function Nonefunction Nonefunction layer
Annotated Snippet
static struct pci_driver sch_pci_driver = {
.name = DRV_NAME,
.id_table = sch_pci_tbl,
.probe = sch_init_one,
.remove = ata_pci_remove_one,
#ifdef CONFIG_PM_SLEEP
.suspend = ata_pci_device_suspend,
.resume = ata_pci_device_resume,
#endif
};
static const struct scsi_host_template sch_sht = {
ATA_BMDMA_SHT(DRV_NAME),
};
static struct ata_port_operations sch_pata_ops = {
.inherits = &ata_bmdma_port_ops,
.cable_detect = ata_cable_unknown,
.set_piomode = sch_set_piomode,
.set_dmamode = sch_set_dmamode,
};
static const struct ata_port_info sch_port_info = {
.flags = ATA_FLAG_SLAVE_POSS,
.pio_mask = ATA_PIO4,
.mwdma_mask = ATA_MWDMA2,
.udma_mask = ATA_UDMA5,
.port_ops = &sch_pata_ops,
};
MODULE_AUTHOR("Alek Du <alek.du@intel.com>");
MODULE_DESCRIPTION("SCSI low-level driver for Intel SCH PATA controllers");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, sch_pci_tbl);
MODULE_VERSION(DRV_VERSION);
/**
* sch_set_piomode - Initialize host controller PATA PIO timings
* @ap: Port whose timings we are configuring
* @adev: ATA device
*
* Set PIO mode for device, in host controller PCI config space.
*
* LOCKING:
* None (inherited from caller).
*/
static void sch_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
unsigned int pio = adev->pio_mode - XFER_PIO_0;
struct pci_dev *dev = to_pci_dev(ap->host->dev);
unsigned int port = adev->devno ? D1TIM : D0TIM;
unsigned int data;
pci_read_config_dword(dev, port, &data);
/* see SCH datasheet page 351 */
/* set PIO mode */
data &= ~(PM | PPE);
data |= pio;
/* enable PPE for block device */
if (adev->class == ATA_DEV_ATA)
data |= PPE;
pci_write_config_dword(dev, port, data);
}
/**
* sch_set_dmamode - Initialize host controller PATA DMA timings
* @ap: Port whose timings we are configuring
* @adev: ATA device
*
* Set MW/UDMA mode for device, in host controller PCI config space.
*
* LOCKING:
* None (inherited from caller).
*/
static void sch_set_dmamode(struct ata_port *ap, struct ata_device *adev)
{
unsigned int dma_mode = adev->dma_mode;
struct pci_dev *dev = to_pci_dev(ap->host->dev);
unsigned int port = adev->devno ? D1TIM : D0TIM;
unsigned int data;
pci_read_config_dword(dev, port, &data);
/* see SCH datasheet page 351 */
if (dma_mode >= XFER_UDMA_0) {
/* enable Synchronous DMA mode */
data |= USD;
data &= ~UDM;
data |= (dma_mode - XFER_UDMA_0) << 16;
Annotation
- Immediate include surface: `linux/kernel.h`, `linux/module.h`, `linux/pci.h`, `linux/blkdev.h`, `linux/delay.h`, `linux/device.h`, `scsi/scsi_host.h`, `linux/libata.h`.
- Detected declarations: `function None`, `function None`, `function layer`.
- Atlas domain: Driver Families / drivers/ata.
- Implementation status: pattern implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.