d29389de0b
Generalize the old at91rm9200 "bootstrap" bitbanging SPI master driver as "spi_gpio", so it works with arbitrary GPIOs and can be configured through platform_data. Such SPI masters support: - any number of bus instances (bus_num is the platform_device.id) - any number of chipselects (one GPIO per spi_device) - all four SPI_MODE values, and SPI_CS_HIGH - i/o word sizes from 1 to 32 bits; - devices configured as with any other spi_master controller When configured using platform_data, this provides relatively low clock rates. On platforms that support inlined GPIO calls, significantly improved transfer speeds are also possible with a semi-custom driver. (It's still painful when accessing flash memory, but less so.) Sanity checked by using this version to replace both native controllers on a board with six different SPI slaves, relying on three different SPI_MODE_* values and both SPI_CS_HIGH settings for correct operation. [akpm@linux-foundation.org: cleanups] Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Magnus Damm <damm@igel.co.jp> Tested-by: Magnus Damm <damm@igel.co.jp> Cc: Torgil Svensson <torgil.svensson@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| .. | ||
| acpi | ||
| asm-arm | ||
| asm-frv | ||
| asm-generic | ||
| asm-h8300 | ||
| asm-m32r | ||
| asm-m68k | ||
| asm-mn10300 | ||
| asm-xtensa | ||
| crypto | ||
| drm | ||
| keys | ||
| linux | ||
| math-emu | ||
| media | ||
| mtd | ||
| net | ||
| pcmcia | ||
| rdma | ||
| rxrpc | ||
| scsi | ||
| sound | ||
| trace | ||
| video | ||
| xen | ||
| Kbuild | ||