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Devctl and Ioctl Commands
DCMD_SDIO_*
DCMD_SDIO_GET_HCCAP
Get the host controller capabilities

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        Detach a device
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        Stop a device handler
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        Get the host controller capabilities
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        Disable a function interrupt
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DCMD_SDIO_GET_HCCAP

QNX SDP8.0Devctl and Ioctl CommandsDeveloper

Get the host controller capabilities

Synopsis:

#include <mmc/sdio.h>

#define DCMD_SDIO_GET_HCCAP   __DIOF (_DCMD_MISC, 0x06, uint32_t)

Arguments to devctl():


Argument	Value
`filedes`	A file descriptor that you obtained by opening the device
`dcmd`	DCMD_SDIO_GET_HCCAP
`dev_data_ptr`	A pointer to a uint32_t
`n_bytes`	`sizeof(uint32_t)`
`dev_info_ptr`	NULL

Description:

This command gets the device's host controller capabilities.

Input:

None.

Output:

The host controller capabilities; a bitwise OR of the following:

SDIO_HCAP_DMA — the controller supports DMA
SDIO_HCAP_SG — DMA supports scatter/gather
SDIO_HCAP_PIO — the controller supports PIO
SDIO_HCAP_18V — 1.8v is supported
SDIO_HCAP_30V — 3.0v is supported
SDIO_HCAP_33V — 3.3v is supported
SDIO_HCAP_BW1 — 1-bit bus is supported
SDIO_HCAP_BW4 — 4-bit bus is supported
SDIO_HCAP_BW8 — 8-bit bus is supported
SDIO_HCAP_CD_INTR — the host supports card detect interrupt
SDIO_HCAP_ACMD12 — auto stop command(ACMD12) is supported
SDIO_HCAP_HS — high-speed devices are supported

See also:

devctl() in the QNX OS C Library Reference

Page updated: March 05, 2025