SDIO Usage Guidelines

• How to Use
• Opening an SDIO Controller
• Claiming a Host Exclusively
• Enabling the SDIO Device
• Claiming an SDIO IRQ
• Performing SDIO Communication
• Releasing the SDIO IRQ
• Disabling the SDIO Device
• Releasing the Exclusively Claimed Host
• Closing an SDIO Controller

How to Use

Figure 1 illustrates the process of using an SDIO.

Figure 1 Process of using an SDIO

Opening an SDIO Controller

Before performing SDIO communication, obtain the device handle of an SDIO controller by calling SdioOpen. This function returns the device handle of the SDIO controller with a specified bus number.

DevHandle SdioOpen(int16_t busNum);

Table 1 Parameters and return values of SdioOpen

The following example shows how to open an SDIO controller.

DevHandle handle = NULL;
int16_t busNum = 1;
/* Open an SDIO controller whose bus number is 1. */
handle = SdioOpen(busNum);
if (handle == NULL) {
    HDF_LOGE("SdioOpen: failed!\n");
}

Claiming a Host Exclusively

After obtaining the device handle of an SDIO controller, exclusively claim the host before performing subsequent operations on the SDIO device.

void SdioClaimHost(DevHandle handle);

Table 2 Parameter description of SdioClaimHost

The following example shows how to exclusively claim a host.

SdioClaimHost(handle); /* Claim a host exclusively. */

Enabling the SDIO Device

Before accessing a register, enable the SDIO device.

int32_t SdioEnableFunc(DevHandle handle);

Table 3 Parameters and return values of SdioEnableFunc

The following example shows how to enable the SDIO device.

int32_t ret;
/* Enable the SDIO device. */
ret = SdioEnableFunc(handle);
if (ret != 0) {
    HDF_LOGE("SdioEnableFunc: failed, ret %d\n", ret);
}

Claiming an SDIO IRQ

Before SDIO communication, claim an SDIO IRQ.

int32_t SdioClaimIrq(DevHandle handle, SdioIrqHandler *handler);

Table 4 Parameters and return values of SdioClaimIrq

The following example shows how to claim an SDIO IRQ.

/* Implement the SDIO IRQ function based on the application. */
static void SdioIrqFunc(void *data)
{
    if (data == NULL) {
        HDF_LOGE("SdioIrqFunc: data is NULL.\n");
        return;
    }
    /* You need to add specific implementations. */
}

int32_t ret;
/* Claim an SDIO IRQ. */
ret = SdioClaimIrq(handle, SdioIrqFunc);
if (ret != 0) {
    HDF_LOGE("SdioClaimIrq: failed, ret %d\n", ret);
}

Performing SDIO Communication

• Incrementally write a given length of data into the SDIO device.

The corresponding function is as follows:

int32_t SdioWriteBytes(DevHandle handle, uint8_t *data, uint32_t addr, uint32_t size, uint32_t timeOut);

Table 5 Parameters and return values of SdioWriteBytes

The following example shows how to incrementally write a given length of data into the SDIO device.

int32_t ret;
uint8_t wbuff[] = {1,2,3,4,5};
uint32_t addr = 0x100 + 0x09;
/* Incrementally write 5-byte data into the start address 0x109 of the SDIO device. */
ret = SdioWriteBytes(handle, wbuff, addr, sizeof(wbuff) / sizeof(wbuff[0]), 0);
if (ret != 0) {
    HDF_LOGE("SdioWriteBytes: failed, ret %d\n", ret);
}

• Incrementally read a given length of data from the SDIO device.

The corresponding function is as follows:

int32_t SdioReadBytes(DevHandle handle, uint8_t *data, uint32_t addr, uint32_t size, uint32_t timeOut);

Table 6 Parameters and return values of SdioReadBytes

The following example shows how to incrementally read a given length of data from the SDIO device.

int32_t ret;
uint8_t rbuff[5] = {0};
uint32_t addr = 0x100 + 0x09;
/* Incrementally read 5-byte data from the start address 0x109 of the SDIO device. */
ret = SdioReadBytes(handle, rbuff, addr, 5, 0);
if (ret != 0) {
    HDF_LOGE("SdioReadBytes: failed, ret %d\n", ret);
}

• Write a given length of data into the fixed address of an SDIO device.

  The corresponding function is as follows:

  int32_t SdioWriteBytesToFixedAddr(DevHandle handle, uint8_t *data, uint32_t addr, uint32_t size, uint32_t timeOut);

  Table 7 Parameters and return values of SdioWriteBytesToFixedAddr

  Parameter	Description
  handle	Device handle of an SDIO controller.
  data	Pointer to the data to write.
  addr	Fixed address where the data is written into.
  size	Length of the data to write.
  timeOut	Timeout duration for writing data, in milliseconds. If the value is 0, the default value is used.
  Return Value	Description
  0	Data is written into the SDIO device.
  Negative value	Failed to write data into the SDIO device.

  The following example shows how to write a given length of data into the fixed address of an SDIO device.

  int32_t ret;
  uint8_t wbuff[] = {1, 2, 3, 4, 5};
  uint32_t addr = 0x100 + 0x09;
  /* Write 5-byte data into the fixed address 0x109 of the SDIO device. */
  ret = SdioWriteBytesToFixedAddr(handle, wbuff, addr, sizeof(wbuff) / sizeof(wbuff[0]), 0);
  if (ret != 0) {
      HDF_LOGE("SdioWriteBytesToFixedAddr: failed, ret %d\n", ret);
  }

• Read a given length of data from the fixed address of an SDIO device.

  The corresponding function is as follows:

  int32_t SdioReadBytesFromFixedAddr(DevHandle handle, uint8_t *data, uint32_t addr, uint32_t size, uint32_t timeOut);

  Table 8 Parameters and return values of SdioReadBytesFromFixedAddr

  Parameter	Description
  handle	Device handle of an SDIO controller.
  data	Pointer to the data to read.
  addr	Start address where the data is read from.
  size	Length of the data to read.
  timeOut	Timeout duration for reading data, in milliseconds. If the value is 0, the default value is used.
  Return Value	Description
  0	Data is read from the SDIO device.
  Negative value	Failed to read data from the SDIO device.

  The following example shows how to read a given length of data from the fixed address of an SDIO device.

  int32_t ret;
  uint8_t rbuff[5] = {0};
  uint32_t addr = 0x100 + 0x09;
  /* Read 5-byte data from the fixed address 0x109 of the SDIO device. */
  ret = SdioReadBytesFromFixedAddr(handle, rbuff, addr, 5, 0);
  if (ret != 0) {
      HDF_LOGE("SdioReadBytesFromFixedAddr: failed, ret %d\n", ret);
  }

• Write a given length of data into the address space of SDIO function 0.

Currently, only 1-byte data can be written. The corresponding function is as follows:

int32_t SdioWriteBytesToFunc0(DevHandle handle, uint8_t *data, uint32_t addr, uint32_t size, uint32_t timeOut);

Table 9 Parameters and return values of SdioWriteBytesToFunc0

The following example shows how to write a given length of data into the address space of SDIO function 0.

int32_t ret;
uint8_t wbuff = 1;
/* Write 1-byte data into the address 0x2 of SDIO function 0. */
ret = SdioWriteBytesToFunc0(handle, &wbuff, 0x2, 1, 0);
if (ret != 0) {
    HDF_LOGE("SdioWriteBytesToFunc0: failed, ret %d\n", ret);
}

• Read a given length of data from the address space of SDIO function 0.

Currently, only 1-byte data can be read. The corresponding function is as follows:

int32_t SdioReadBytesFromFunc0(DevHandle handle, uint8_t *data, uint32_t addr, uint32_t size, uint32_t timeOut);

Table 10 Parameters and return values of SdioReadBytesFromFunc0

The following example shows how to read a given length of data from the address space of SDIO function 0.

int32_t ret;
uint8_t rbuff;
/* Read 1-byte data from the address 0x2 of SDIO function 0. */
ret = SdioReadBytesFromFunc0(handle, &rbuff, 0x2, 1, 0);
if (ret != 0) {
    HDF_LOGE("SdioReadBytesFromFunc0: failed, ret %d\n", ret);
}

Releasing the SDIO IRQ

After the SDIO communication, release the SDIO IRQ.

int32_t SdioReleaseIrq(DevHandle handle);

Table 11 Parameters and return values of SdioReleaseIrq

The following example shows how to release the SDIO IRQ.

int32_t ret;
/* Release the SDIO IRQ. */
ret = SdioReleaseIrq(handle);
if (ret != 0) {
    HDF_LOGE("SdioReleaseIrq: failed, ret %d\n", ret);
}

Disabling the SDIO Device

After the SDIO communication, disable the SDIO device.

int32_t SdioDisableFunc(DevHandle handle);

Table 12 Parameters and return values of SdioDisableFunc

The following example shows how to disable the SDIO device.

int32_t ret;
/* Disable the SDIO device. */
ret = SdioDisableFunc(handle);
if (ret != 0) {
    HDF_LOGE("SdioDisableFunc: failed, ret %d\n", ret);
}

Releasing the Exclusively Claimed Host

After the SDIO communication, release the exclusively claimed host.

void SdioReleaseHost(DevHandle handle);

Table 13 Parameter description of SdioReleaseHost

The following example shows how to release the exclusively claimed host.

SdioReleaseHost(handle); /* Release the exclusively claimed host. */

Closing an SDIO Controller

After the SDIO communication, close the SDIO controller.

void SdioClose(DevHandle handle);

This function releases the resources requested.

Table 14 Parameter description of SdioClose

The following example shows how to close an SDIO controller.

SdioClose(handle); /* Close an SDIO controller. */