diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-18 10:56:02 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-18 10:56:02 -0700 |
commit | b061c59c27e0385e53c961d9fbd18c1c078d9823 (patch) | |
tree | 56240ef8e98e9e4712ee58aa8e6e3d51f6ab001f /drivers/spi/omap2_mcspi.c | |
parent | 99f4065bac7b8c3f829334b4218a5c2e68cbe440 (diff) | |
parent | 568a60eda2e90a11bb3d7f8ef3f6800e9b60d4e5 (diff) |
Merge branch 'spi/next' of git://git.secretlab.ca/git/linux-2.6
* 'spi/next' of git://git.secretlab.ca/git/linux-2.6: (34 commits)
spi/dw_spi: move dw_spi.h into drivers/spi
spi/dw_spi: Fix missing header
gpio/langwell: Clear edge bit before handling
gpio/langwell: Simplify demux loop
gpio/langwell: Convert irq name space
gpio/langwell: Fix broken irq_eoi change.
gpio; Make Intel chipset gpio drivers depend on x86
gpio/cs5535-gpio: Fix section mismatch
spi/rtc-{ds1390,ds3234,m41t94}: Use spi_get_drvdata() for SPI devices
spi/davinci: Support DMA transfers larger than 65535 words
spi/davinci: Use correct length parameter to dma_map_single calls
gpio: Use __devexit at necessary places
gpio: add MODULE_DEVICE_TABLE to pch_gpio and ml_ioh_gpio
gpio/mcp23s08: support mcp23s17 variant
of_mmc_spi: add card detect irq support
spi/omap_mcspi: catch xfers of non-multiple SPI word size
spi/omap_mcspi: Off-by-one error in finding the right divisor
gpio/pca953x: Fix wrong pointer type
spi/pl022: rid dangling labels
spi: add support for SuperH SPI
...
Diffstat (limited to 'drivers/spi/omap2_mcspi.c')
-rw-r--r-- | drivers/spi/omap2_mcspi.c | 38 |
1 files changed, 24 insertions, 14 deletions
diff --git a/drivers/spi/omap2_mcspi.c b/drivers/spi/omap2_mcspi.c index 36501adc125d..3a5ed06d3d2f 100644 --- a/drivers/spi/omap2_mcspi.c +++ b/drivers/spi/omap2_mcspi.c @@ -467,6 +467,9 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) rx_reg = base + OMAP2_MCSPI_RX0; chstat_reg = base + OMAP2_MCSPI_CHSTAT0; + if (c < (word_len>>3)) + return 0; + if (word_len <= 8) { u8 *rx; const u8 *tx; @@ -514,7 +517,7 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) dev_vdbg(&spi->dev, "read-%d %02x\n", word_len, *(rx - 1)); } - } while (c); + } while (c > (word_len>>3)); } else if (word_len <= 16) { u16 *rx; const u16 *tx; @@ -561,7 +564,7 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) dev_vdbg(&spi->dev, "read-%d %04x\n", word_len, *(rx - 1)); } - } while (c); + } while (c > (word_len>>3)); } else if (word_len <= 32) { u32 *rx; const u32 *tx; @@ -608,7 +611,7 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer) dev_vdbg(&spi->dev, "read-%d %08x\n", word_len, *(rx - 1)); } - } while (c); + } while (c > (word_len>>3)); } /* for TX_ONLY mode, be sure all words have shifted out */ @@ -631,6 +634,17 @@ out: return count - c; } +static u32 omap2_mcspi_calc_divisor(u32 speed_hz) +{ + u32 div; + + for (div = 0; div < 15; div++) + if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div)) + return div; + + return 15; +} + /* called only when no transfer is active to this device */ static int omap2_mcspi_setup_transfer(struct spi_device *spi, struct spi_transfer *t) @@ -653,12 +667,8 @@ static int omap2_mcspi_setup_transfer(struct spi_device *spi, if (t && t->speed_hz) speed_hz = t->speed_hz; - if (speed_hz) { - while (div <= 15 && (OMAP2_MCSPI_MAX_FREQ / (1 << div)) - > speed_hz) - div++; - } else - div = 15; + speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ); + div = omap2_mcspi_calc_divisor(speed_hz); l = mcspi_cached_chconf0(spi); @@ -695,7 +705,7 @@ static int omap2_mcspi_setup_transfer(struct spi_device *spi, mcspi_write_chconf0(spi, l); dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n", - OMAP2_MCSPI_MAX_FREQ / (1 << div), + OMAP2_MCSPI_MAX_FREQ >> div, (spi->mode & SPI_CPHA) ? "trailing" : "leading", (spi->mode & SPI_CPOL) ? "inverted" : "normal"); @@ -996,10 +1006,10 @@ static int omap2_mcspi_transfer(struct spi_device *spi, struct spi_message *m) t->bits_per_word); return -EINVAL; } - if (t->speed_hz && t->speed_hz < OMAP2_MCSPI_MAX_FREQ/(1<<16)) { - dev_dbg(&spi->dev, "%d Hz max exceeds %d\n", - t->speed_hz, - OMAP2_MCSPI_MAX_FREQ/(1<<16)); + if (t->speed_hz && t->speed_hz < (OMAP2_MCSPI_MAX_FREQ >> 15)) { + dev_dbg(&spi->dev, "speed_hz %d below minimum %d Hz\n", + t->speed_hz, + OMAP2_MCSPI_MAX_FREQ >> 15); return -EINVAL; } |