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Viewing changes to drivers/spi/omap2_mcspi.c

  • Committer: Bazaar Package Importer
  • Author(s): Paolo Pisati
  • Date: 2011-06-29 15:23:51 UTC
  • mfrom: (26.1.1 natty-proposed)
  • Revision ID: james.westby@ubuntu.com-20110629152351-xs96tm303d95rpbk
Tags: 3.0.0-1200.2
* Rebased against 3.0.0-6.7
* BSP from TI based on 3.0.0

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Lines of Context:
drivers/spi/omap2_mcspi.c
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        unsigned int            count, c;
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        unsigned long           base, tx_reg, rx_reg;
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        int                     word_len, data_type, element_count;
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        int                     elements;
 
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        int                     elements = 0;
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        u32                     l;
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        u8                      * rx;
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        const u8                * tx;
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        rx_reg          = base + OMAP2_MCSPI_RX0;
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        chstat_reg      = base + OMAP2_MCSPI_CHSTAT0;
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        if (c < (word_len>>3))
 
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                return 0;
 
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        if (word_len <= 8) {
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                u8              *rx;
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                const u8        *tx;
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                                dev_vdbg(&spi->dev, "read-%d %04x\n",
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                                                word_len, *(rx - 1));
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                        }
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                } while (c);
 
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                } while (c >= 2);
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        } else if (word_len <= 32) {
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                u32             *rx;
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                const u32       *tx;
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                                dev_vdbg(&spi->dev, "read-%d %08x\n",
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                                                word_len, *(rx - 1));
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                        }
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                } while (c);
 
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                } while (c >= 4);
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        }
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        /* for TX_ONLY mode, be sure all words have shifted out */
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        return count - c;
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}
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static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
 
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{
 
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        u32 div;
 
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        for (div = 0; div < 15; div++)
 
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                if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
 
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                        return div;
 
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        return 15;
 
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}
 
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/* called only when no transfer is active to this device */
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static int omap2_mcspi_setup_transfer(struct spi_device *spi,
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                struct spi_transfer *t)
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        if (t && t->speed_hz)
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                speed_hz = t->speed_hz;
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        if (speed_hz) {
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                while (div <= 15 && (OMAP2_MCSPI_MAX_FREQ / (1 << div))
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                                        > speed_hz)
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                        div++;
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        } else
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                div = 15;
 
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        speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
 
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        div = omap2_mcspi_calc_divisor(speed_hz);
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        l = mcspi_cached_chconf0(spi);
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        mcspi_write_chconf0(spi, l);
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        dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
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                        OMAP2_MCSPI_MAX_FREQ / (1 << div),
 
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                        OMAP2_MCSPI_MAX_FREQ >> div,
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                        (spi->mode & SPI_CPHA) ? "trailing" : "leading",
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                        (spi->mode & SPI_CPOL) ? "inverted" : "normal");
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                                        t->bits_per_word);
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                        return -EINVAL;
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                }
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                if (t->speed_hz && t->speed_hz < OMAP2_MCSPI_MAX_FREQ/(1<<16)) {
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                        dev_dbg(&spi->dev, "%d Hz max exceeds %d\n",
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                                        t->speed_hz,
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                                        OMAP2_MCSPI_MAX_FREQ/(1<<16));
 
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                if (t->speed_hz && t->speed_hz < (OMAP2_MCSPI_MAX_FREQ >> 15)) {
 
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                        dev_dbg(&spi->dev, "speed_hz %d below minimum %d Hz\n",
 
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                                t->speed_hz,
 
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                                OMAP2_MCSPI_MAX_FREQ >> 15);
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                        return -EINVAL;
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                }
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