DCMD_SDIO_READ_IOREG

QNX SDP8.0Devctl and Ioctl CommandsDeveloper

Read an I/O register

Synopsis:

#include <mmc/sdio.h>

#define DCMD_SDIO_READ_IOREG    __DIOTF(_DCMD_MISC, 0x01, sdio_ioreg_t)

Arguments to devctl():

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

Description:

This command reads an I/O register. The sdio_ioreg_t structure is defined as follows: 

typedef struct _sdio_ioreg_t {
        uint8_t         func;
        uint8_t         val;
        uint8_t         rsvd[2];
        uint32_t        reg;
} sdio_ioreg_t;

The members include:

func
The function number
val
reg
The register to be read.

Input:

Set the func and reg members.

Output:

The value read from the register.

See also:

devctl() in the QNX OS C Library Reference

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