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authorBrian Niebuhr <bniebuhr@efjohnson.com>2010-08-19 12:15:22 +0530
committerSekhar Nori <nsekhar@ti.com>2010-11-18 18:38:26 +0530
commit25f33512f6ae7e37d7b3d353d57d4d6d066033ce (patch)
tree2c458d56e07f842c78fd31f7e13a28fe1b7a9361 /drivers/spi/davinci_spi.c
parent53a31b07c5aea4001bbb36ddd5ef2addffc7ccbd (diff)
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 <bniebuhr@efjohnson.com> Tested-By: Michael Williamson <michael.williamson@criticallink.com> Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Diffstat (limited to 'drivers/spi/davinci_spi.c')
-rw-r--r--drivers/spi/davinci_spi.c154
1 files changed, 49 insertions, 105 deletions
diff --git a/drivers/spi/davinci_spi.c b/drivers/spi/davinci_spi.c
index d4320f78407..34b28fe2d32 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;