mirror of https://gitee.com/openkylin/linux.git
8051effcbc
This patch is V2 of SPI Master support for the SuperH MSIOF. Full duplex, spi mode 0-3, active high cs, 3-wire and lsb first should all be supported, but the driver has so far only been tested with "mmc_spi". The MSIOF hardware comes with 32-bit FIFOs for receive and transmit, and this driver simply breaks the SPI messages into FIFO-sized chunks. The MSIOF hardware manages the pins for clock, receive and transmit (sck/miso/mosi), but the chip select pin is managed by software and must be configured as a regular GPIO pin by the board code. Performance wise there is still room for improvement, but on a Ecovec board with the built-in sh7724 MSIOF0 this driver gets Mini-sd read speeds of about half a megabyte per second. Future work include better clock setup and merging of 8-bit transfers into 32-bit words to reduce interrupt load and improve throughput. Signed-off-by: Magnus Damm <damm@opensource.se> Signed-off-by: Grant Likely <grant.likely@secretlab.ca> |
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| .. | ||
| acpi | ||
| asm-generic | ||
| crypto | ||
| drm | ||
| keys | ||
| linux | ||
| math-emu | ||
| media | ||
| mtd | ||
| net | ||
| pcmcia | ||
| rdma | ||
| rxrpc | ||
| scsi | ||
| sound | ||
| trace | ||
| video | ||
| xen | ||
| Kbuild | ||