From 25f33512f6ae7e37d7b3d353d57d4d6d066033ce Mon Sep 17 00:00:00 2001 From: Brian Niebuhr Date: Thu, 19 Aug 2010 12:15:22 +0530 Subject: [PATCH] spi: davinci: consolidate setup of SPIFMTn in one function Consolidate the setup of SPIFMTn register under davinci_spi_setup_transfer() simplifying the code and avoiding unnecessary reads and writes to the register. The two inline functions {set|clear}_fmt_bits() can be eliminated because of this. Signed-off-by: Brian Niebuhr Tested-By: Michael Williamson Signed-off-by: Sekhar Nori --- drivers/spi/davinci_spi.c | 154 ++++++++++++-------------------------- 1 file changed, 49 insertions(+), 105 deletions(-) diff --git a/drivers/spi/davinci_spi.c b/drivers/spi/davinci_spi.c index d4320f784070..34b28fe2d327 100644 --- a/drivers/spi/davinci_spi.c +++ b/drivers/spi/davinci_spi.c @@ -52,7 +52,6 @@ #define SPIFMT_ODD_PARITY_MASK BIT(23) #define SPIFMT_WDELAY_MASK 0x3f000000u #define SPIFMT_WDELAY_SHIFT 24 -#define SPIFMT_CHARLEN_MASK 0x0000001Fu #define SPIFMT_PRESCALE_SHIFT 8 @@ -212,16 +211,6 @@ static inline void clear_io_bits(void __iomem *addr, u32 bits) iowrite32(v, addr); } -static inline void set_fmt_bits(void __iomem *addr, u32 bits, int cs_num) -{ - set_io_bits(addr + SPIFMT0 + (0x4 * cs_num), bits); -} - -static inline void clear_fmt_bits(void __iomem *addr, u32 bits, int cs_num) -{ - clear_io_bits(addr + SPIFMT0 + (0x4 * cs_num), bits); -} - static void davinci_spi_set_dma_req(const struct spi_device *spi, int enable) { struct davinci_spi *davinci_spi = spi_master_get_devdata(spi->master); @@ -306,10 +295,14 @@ static int davinci_spi_setup_transfer(struct spi_device *spi, { struct davinci_spi *davinci_spi; + struct davinci_spi_config *spicfg; u8 bits_per_word = 0; - u32 hz = 0, prescale = 0; + u32 hz = 0, spifmt = 0, prescale = 0; davinci_spi = spi_master_get_devdata(spi->master); + spicfg = (struct davinci_spi_config *)spi->controller_data; + if (!spicfg) + spicfg = &davinci_spi_default_cfg; if (t) { bits_per_word = t->bits_per_word; @@ -338,18 +331,55 @@ static int davinci_spi_setup_transfer(struct spi_device *spi, if (!hz) hz = spi->max_speed_hz; + /* Set up SPIFMTn register, unique to this chipselect. */ + prescale = davinci_spi_get_prescale(davinci_spi, hz); if (prescale < 0) return prescale; - clear_fmt_bits(davinci_spi->base, SPIFMT_CHARLEN_MASK, - spi->chip_select); - set_fmt_bits(davinci_spi->base, bits_per_word & 0x1f, - spi->chip_select); + spifmt = (prescale << SPIFMT_PRESCALE_SHIFT) | (bits_per_word & 0x1f); + + if (spi->mode & SPI_LSB_FIRST) + spifmt |= SPIFMT_SHIFTDIR_MASK; + + if (spi->mode & SPI_CPOL) + spifmt |= SPIFMT_POLARITY_MASK; + + if (!(spi->mode & SPI_CPHA)) + spifmt |= SPIFMT_PHASE_MASK; + + /* + * Version 1 hardware supports two basic SPI modes: + * - Standard SPI mode uses 4 pins, with chipselect + * - 3 pin SPI is a 4 pin variant without CS (SPI_NO_CS) + * (distinct from SPI_3WIRE, with just one data wire; + * or similar variants without MOSI or without MISO) + * + * Version 2 hardware supports an optional handshaking signal, + * so it can support two more modes: + * - 5 pin SPI variant is standard SPI plus SPI_READY + * - 4 pin with enable is (SPI_READY | SPI_NO_CS) + */ + + if (davinci_spi->version == SPI_VERSION_2) { + + spifmt |= ((spicfg->wdelay << SPIFMT_WDELAY_SHIFT) + & SPIFMT_WDELAY_MASK); - clear_fmt_bits(davinci_spi->base, 0x0000ff00, spi->chip_select); - set_fmt_bits(davinci_spi->base, - prescale << SPIFMT_PRESCALE_SHIFT, spi->chip_select); + if (spicfg->odd_parity) + spifmt |= SPIFMT_ODD_PARITY_MASK; + + if (spicfg->parity_enable) + spifmt |= SPIFMT_PARITYENA_MASK; + + if (spicfg->timer_disable) + spifmt |= SPIFMT_DISTIMER_MASK; + + if (spi->mode & SPI_READY) + spifmt |= SPIFMT_WAITENA_MASK; + } + + iowrite32(spifmt, davinci_spi->base + SPIFMT0); return 0; } @@ -436,12 +466,8 @@ static int davinci_spi_setup(struct spi_device *spi) int retval; struct davinci_spi *davinci_spi; struct davinci_spi_dma *davinci_spi_dma; - struct davinci_spi_config *spicfg; davinci_spi = spi_master_get_devdata(spi->master); - spicfg = (struct davinci_spi_config *)spi->controller_data; - if (!spicfg) - spicfg = &davinci_spi_default_cfg; /* if bits per word length is zero then set it default 8 */ if (!spi->bits_per_word) @@ -460,88 +486,6 @@ static int davinci_spi_setup(struct spi_device *spi) } } - /* - * Set up SPIFMTn register, unique to this chipselect. - * - * NOTE: we could do all of these with one write. Also, some - * of the "version 2" features are found in chips that don't - * support all of them... - */ - if (spi->mode & SPI_LSB_FIRST) - set_fmt_bits(davinci_spi->base, SPIFMT_SHIFTDIR_MASK, - spi->chip_select); - else - clear_fmt_bits(davinci_spi->base, SPIFMT_SHIFTDIR_MASK, - spi->chip_select); - - if (spi->mode & SPI_CPOL) - set_fmt_bits(davinci_spi->base, SPIFMT_POLARITY_MASK, - spi->chip_select); - else - clear_fmt_bits(davinci_spi->base, SPIFMT_POLARITY_MASK, - spi->chip_select); - - if (!(spi->mode & SPI_CPHA)) - set_fmt_bits(davinci_spi->base, SPIFMT_PHASE_MASK, - spi->chip_select); - else - clear_fmt_bits(davinci_spi->base, SPIFMT_PHASE_MASK, - spi->chip_select); - - /* - * Version 1 hardware supports two basic SPI modes: - * - Standard SPI mode uses 4 pins, with chipselect - * - 3 pin SPI is a 4 pin variant without CS (SPI_NO_CS) - * (distinct from SPI_3WIRE, with just one data wire; - * or similar variants without MOSI or without MISO) - * - * Version 2 hardware supports an optional handshaking signal, - * so it can support two more modes: - * - 5 pin SPI variant is standard SPI plus SPI_READY - * - 4 pin with enable is (SPI_READY | SPI_NO_CS) - */ - - if (davinci_spi->version == SPI_VERSION_2) { - - clear_fmt_bits(davinci_spi->base, SPIFMT_WDELAY_MASK, - spi->chip_select); - set_fmt_bits(davinci_spi->base, - (spicfg->wdelay << SPIFMT_WDELAY_SHIFT) & - SPIFMT_WDELAY_MASK, spi->chip_select); - - if (spicfg->odd_parity) - set_fmt_bits(davinci_spi->base, SPIFMT_ODD_PARITY_MASK, - spi->chip_select); - else - clear_fmt_bits(davinci_spi->base, - SPIFMT_ODD_PARITY_MASK, - spi->chip_select); - - if (spicfg->parity_enable) - set_fmt_bits(davinci_spi->base, SPIFMT_PARITYENA_MASK, - spi->chip_select); - else - clear_fmt_bits(davinci_spi->base, SPIFMT_PARITYENA_MASK, - spi->chip_select); - - if (spicfg->timer_disable) - set_fmt_bits(davinci_spi->base, SPIFMT_DISTIMER_MASK, - spi->chip_select); - else - clear_fmt_bits(davinci_spi->base, SPIFMT_DISTIMER_MASK, - spi->chip_select); - - if (spi->mode & SPI_READY) - set_fmt_bits(davinci_spi->base, - SPIFMT_WAITENA_MASK, - spi->chip_select); - else - clear_fmt_bits(davinci_spi->base, - SPIFMT_WAITENA_MASK, - spi->chip_select); - - } - retval = davinci_spi_setup_transfer(spi, NULL); return retval; -- GitLab