Winbond W83L528G-A SDIO controller support

[Shawn Rutledge]

I discovered CONFIG_MMC_TEST, so thought I would give it a try, but
when I insert an SD flash card this Winbond behaves less well than for
SDIO devices, so I cannot see it as a mass storage device.  Is that a
prerequisite to doing the test?

<7>sdhci [sdhci_irq()]: *** mmc1 got interrupt: 0x00000001
<7>sdhci [sdhci_irq()]: *** mmc1 got interrupt: 0x00000009
<3>mmc1: Got command interrupt 0x00000001 even though no command
operation was in progress.
<7>sdhci: ============== REGISTER DUMP ==============
<7>sdhci: Sys addr: 0x2e40c160 | Version:  0x00000100
<7>sdhci: Blk size: 0x00007008 | Blk cnt:  0x00000000
<7>sdhci: Argument: 0x00000000 | Trn mode: 0x00000013
<7>sdhci: Present:  0x01ff0000 | Host ctl: 0x00000001
<7>sdhci: Power:    0x0000000d | Blk gap:  0x00000000
<7>sdhci: Wake-up:  0x00000000 | Clock:    0x00008007
<7>sdhci: Timeout:  0x00000005 | Int stat: 0x0000000a
<7>sdhci: Int enab: 0x00ff00fb | Sig enab: 0x00ff00fb
<7>sdhci: AC12 err: 0x00000000 | Slot int: 0x00000000
<7>sdhci: Caps:     0x07602188 | Max curr: 0x00000000
<7>sdhci: ===========================================
<3>mmc1: Timeout waiting for hardware interrupt.
<7>sdhci: ============== REGISTER DUMP ==============
<7>sdhci: Sys addr: 0x2e40c160 | Version:  0x00000100
<7>sdhci: Blk size: 0x00007008 | Blk cnt:  0x00000000
<7>sdhci: Argument: 0x00000000 | Trn mode: 0x00000013
<7>sdhci: Present:  0x01ff0000 | Host ctl: 0x00000001
<7>sdhci: Power:    0x0000000d | Blk gap:  0x00000000
<7>sdhci: Wake-up:  0x00000000 | Clock:    0x00008007
<7>sdhci: Timeout:  0x00000005 | Int stat: 0x00000000
<7>sdhci: Int enab: 0x00ff00fb | Sig enab: 0x00ff00fb
<7>sdhci: AC12 err: 0x00000000 | Slot int: 0x00000000
<7>sdhci: Caps:     0x07602188 | Max curr: 0x00000000
<7>sdhci: ===========================================
<7>mmc1: req done (CMD51): 0: ffffffff 00000000 00000000 00000000
<7>mmc1:     0 bytes transferred: -110
<7>mmc1: clock 0Hz busmode 1 powermode 0 cs 0 Vdd 0 width 0 timing 0
<3>mmc1: error -110 whilst initialising SD card
<7>mmc1: clock 0Hz busmode 1 powermode 0 cs 0 Vdd 0 width 0 timing 0