NetDev_MII_Rd()

The next function to implement is the (R)MII read/Phy_RegRd() function. This function is generally implemented within the Ethernet device driver file, since (R)MII bus reads are generally associated with the MAC device. In the case that the PHY communication mechanism is separate from the MAC, then a handler function may be provided within the net_bsp.c file and called from the device driver file instead.

Note: This function must be implemented with a timeout and should not block indefinitely should the PHY fail to respond.

Files

Every device driver’s net_dev.c

Prototype

          static void NetDev_MII_Rd (NET_IF     *pif,
                                     CPU_INT08U  phy_addr,
                                     CPU_INT08U  reg_addr,
                                     CPU_INT16U *p_data,
                                     NET_ERR    *perr);

Note that since every device driver’s Phy_RegRd()/MII_Rd() function is accessed only by function pointer via the device driver’s API structure, it doesn’t need to be globally available and should therefore be declared as ‘static’.

Arguments

pif

Pointer to the interface to read a (R)MII PHY register.

phy_addr

The bus address of the PHY.

reg_addr

The MII register number to read.

p_data

Pointer to a address to store the content of the PHY register being read.

perr

Pointer to variable that will receive the return error code from this function.

Returned Value

None.

Required Configuration

None.

Notes/Warnings

None.