[PATCH] MMC/SD SPI-mode driver

[Warner Losh]

On Apr 10, 2013, at 5:22 PM, Adrian Chadd wrote:
> On 10 April 2013 11:50, Ian Lepore <ian at freebsd.org> wrote:
>> Maybe something like this could work?
>> 
>> static int
>> ar71xx_spi_transfer(device_t dev, device_t child, struct spi_command *cmd)
>> {
>>    if (cmd->cs == sc->magic_mapped_flash_chipsel &&
>>        cmd->tx_cmd == NULL && cmd->tx_data == NULL &&
>>        *(uint8_t *)cmd->rx_cmd == SPIFLASH_READ_OPCODE &&
>>        /* maybe some other constraints I don't know about */
>>        /* maybe even check that child is the mx25l driver */)
>>            return do_magic_mapped_read(...);
>>    else
>>            return do_mundane_nonmapped_transfer(...);
>> }
> 
> So you're special casing it in the bus code rather than the driver
> code. It's still ugly, but it's hid from the driver.

At least in the bus code we won't have to put this code into each of our SPI flash drivers...

Warner