diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2010-05-25 12:04:17 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-05-25 12:04:17 -0700 |
| commit | 702c0b04978ce316ec05f4d0a9c148fac124335b (patch) | |
| tree | 3908c5821221d950a6b1a7e2e898899e63e7d437 /drivers/spi/davinci_spi.c | |
| parent | c19eb8f0d1bd442ed1aff0b413dd822620771c29 (diff) | |
| parent | bf6a67ee3427ab142136e03e90d0b67ecbca5ff2 (diff) | |
Merge branch 'next-spi' of git://git.secretlab.ca/git/linux-2.6
* 'next-spi' of git://git.secretlab.ca/git/linux-2.6:
spi/xilinx: Fix compile error
spi/davinci: Fix clock prescale factor computation
spi: move bitbang txrx utility functions to private header
spi/mpc5121: Add SPI master driver for MPC5121 PSC
powerpc/mpc5121: move PSC FIFO memory init to platform code
spi/ep93xx: implemented driver for Cirrus EP93xx SPI controller
Documentation/spi/* compile warning fix
spi/omap2_mcspi: Check params before dereference or use
spi/omap2_mcspi: add turbo mode support
spi/omap2_mcspi: change default DMA_MIN_BYTES value to 160
spi/pl022: fix stop queue procedure
spi/pl022: add support for the PL023 derivate
spi/pl022: fix up differences between ARM and ST versions
spi/spi_mpc8xxx: Do not use map_tx_dma to unmap rx_dma
spi/spi_mpc8xxx: Fix QE mode Litte Endian
spi/spi_mpc8xxx: fix potential memory corruption.
Diffstat (limited to 'drivers/spi/davinci_spi.c')
| -rw-r--r-- | drivers/spi/davinci_spi.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/drivers/spi/davinci_spi.c b/drivers/spi/davinci_spi.c index 95afb6b77395..b85090caf7cf 100644 --- a/drivers/spi/davinci_spi.c +++ b/drivers/spi/davinci_spi.c @@ -301,7 +301,7 @@ static int davinci_spi_setup_transfer(struct spi_device *spi, struct davinci_spi *davinci_spi; struct davinci_spi_platform_data *pdata; u8 bits_per_word = 0; - u32 hz = 0, prescale; + u32 hz = 0, prescale = 0, clkspeed; davinci_spi = spi_master_get_devdata(spi->master); pdata = davinci_spi->pdata; @@ -338,10 +338,16 @@ static int davinci_spi_setup_transfer(struct spi_device *spi, set_fmt_bits(davinci_spi->base, bits_per_word & 0x1f, spi->chip_select); - prescale = ((clk_get_rate(davinci_spi->clk) / hz) - 1) & 0xff; + clkspeed = clk_get_rate(davinci_spi->clk); + if (hz > clkspeed / 2) + prescale = 1 << 8; + if (hz < clkspeed / 256) + prescale = 255 << 8; + if (!prescale) + prescale = ((clkspeed / hz - 1) << 8) & 0x0000ff00; clear_fmt_bits(davinci_spi->base, 0x0000ff00, spi->chip_select); - set_fmt_bits(davinci_spi->base, prescale << 8, spi->chip_select); + set_fmt_bits(davinci_spi->base, prescale, spi->chip_select); return 0; } |