From: Brian Niebuhr <bnieb...@efjohnson.com>
Let davinci_spi_chipselect() perform both activation and
deactivation of chip selects. This lets spi_bitbang fully
control chip select activation, as intended by the SPI API.
With this change, the chip select activation code need not
be duplicated in davinci_spi_bufs_{pio|dma}().
Also, keeping chip select active control is removed as a
platform data and simply controlled using information from
spi_bitbang on whether chip slect should be activated or
de-activated.
Signed-off-by: Brian Niebuhr <bnieb...@efjohnson.com>
Tested-By: Michael Williamson <michael.william...@criticallink.com>
Signed-off-by: Sekhar Nori <nsek...@ti.com>
---
arch/arm/mach-davinci/dm355.c | 1 -
arch/arm/mach-davinci/dm365.c | 1 -
arch/arm/mach-davinci/include/mach/spi.h | 1 -
drivers/spi/davinci_spi.c | 53 ++++++++++-------------------
4 files changed, 18 insertions(+), 38 deletions(-)
diff --git a/arch/arm/mach-davinci/dm355.c b/arch/arm/mach-davinci/dm355.c
index 9be261b..6a76dfa 100644
--- a/arch/arm/mach-davinci/dm355.c
+++ b/arch/arm/mach-davinci/dm355.c
@@ -413,7 +413,6 @@ static struct davinci_spi_platform_data dm355_spi0_pdata = {
.version = SPI_VERSION_1,
.num_chipselect = 2,
.clk_internal = 1,
- .cs_hold = 1,
.intr_level = 0,
.poll_mode = 1, /* 0 -> interrupt mode 1-> polling mode */
.c2tdelay = 0,
diff --git a/arch/arm/mach-davinci/dm365.c b/arch/arm/mach-davinci/dm365.c
index a12065e..cd623db 100644
--- a/arch/arm/mach-davinci/dm365.c
+++ b/arch/arm/mach-davinci/dm365.c
@@ -626,7 +626,6 @@ static struct davinci_spi_platform_data dm365_spi0_pdata = {
.version = SPI_VERSION_1,
.num_chipselect = 2,
.clk_internal = 1,
- .cs_hold = 1,
.intr_level = 0,
.poll_mode = 1, /* 0 -> interrupt mode 1-> polling mode */
.c2tdelay = 0,
diff --git a/arch/arm/mach-davinci/include/mach/spi.h
b/arch/arm/mach-davinci/include/mach/spi.h
index 910efbf..2cb326e 100644
--- a/arch/arm/mach-davinci/include/mach/spi.h
+++ b/arch/arm/mach-davinci/include/mach/spi.h
@@ -33,7 +33,6 @@ struct davinci_spi_platform_data {
u8 wait_enable;
u8 timer_disable;
u8 clk_internal;
- u8 cs_hold;
u8 intr_level;
u8 poll_mode;
u8 use_dma;
diff --git a/drivers/spi/davinci_spi.c b/drivers/spi/davinci_spi.c
index d6b6a49..105c686 100644
--- a/drivers/spi/davinci_spi.c
+++ b/drivers/spi/davinci_spi.c
@@ -66,7 +66,7 @@
#define SPI_INTLVL_0 0x00000000u
/* SPIDAT1 */
-#define SPIDAT1_CSHOLD_SHIFT 28
+#define SPIDAT1_CSHOLD_MASK BIT(28)
#define SPIDAT1_CSNR_SHIFT 16
#define SPIGCR1_CLKMOD_MASK BIT(1)
#define SPIGCR1_MASTER_MASK BIT(0)
@@ -235,7 +235,8 @@ static void davinci_spi_chipselect(struct spi_device *spi,
int value)
{
struct davinci_spi *davinci_spi;
struct davinci_spi_platform_data *pdata;
- u32 data1_reg_val = 0;
+ u32 data1_reg_val;
+ u8 chip_sel = spi->chip_select;
davinci_spi = spi_master_get_devdata(spi->master);
pdata = davinci_spi->pdata;
@@ -244,14 +245,17 @@ static void davinci_spi_chipselect(struct spi_device
*spi, int value)
* Board specific chip select logic decides the polarity and cs
* line for the controller
*/
- if (value == BITBANG_CS_INACTIVE) {
- data1_reg_val |= CS_DEFAULT << SPIDAT1_CSNR_SHIFT;
- iowrite32(data1_reg_val, davinci_spi->base + SPIDAT1);
-
- while ((ioread32(davinci_spi->base + SPIBUF)
- & SPIBUF_RXEMPTY_MASK) == 0)
- cpu_relax();
+ data1_reg_val = CS_DEFAULT << SPIDAT1_CSNR_SHIFT;
+ if (value == BITBANG_CS_ACTIVE) {
+ data1_reg_val |= SPIDAT1_CSHOLD_MASK;
+ data1_reg_val &= ~((0x1 << chip_sel) << SPIDAT1_CSNR_SHIFT);
}
+
+ iowrite32(data1_reg_val, davinci_spi->base + SPIDAT1);
+ while ((ioread32(davinci_spi->base + SPIBUF)
+ & SPIBUF_RXEMPTY_MASK) == 0)
+ cpu_relax();
+
}
/**
@@ -632,7 +636,7 @@ static int davinci_spi_bufs_pio(struct spi_device *spi,
struct spi_transfer *t)
{
struct davinci_spi *davinci_spi;
int int_status, count, ret;
- u8 conv, tmp;
+ u8 conv;
u32 tx_data, data1_reg_val;
u32 buf_val, flg_val;
struct davinci_spi_platform_data *pdata;
@@ -647,6 +651,8 @@ static int davinci_spi_bufs_pio(struct spi_device *spi,
struct spi_transfer *t)
conv = davinci_spi->slave[spi->chip_select].bytes_per_word;
davinci_spi->count = t->len / conv;
+ data1_reg_val = ioread32(davinci_spi->base + SPIDAT1);
+
INIT_COMPLETION(davinci_spi->done);
ret = davinci_spi_bufs_prep(spi, davinci_spi);
@@ -661,16 +667,6 @@ static int davinci_spi_bufs_pio(struct spi_device *spi,
struct spi_transfer *t)
davinci_spi->base + SPIDELAY);
count = davinci_spi->count;
- data1_reg_val = pdata->cs_hold << SPIDAT1_CSHOLD_SHIFT;
- tmp = ~(0x1 << spi->chip_select);
-
- clear_io_bits(davinci_spi->base + SPIDEF, ~tmp);
-
- data1_reg_val |= tmp << SPIDAT1_CSNR_SHIFT;
-
- while ((ioread32(davinci_spi->base + SPIBUF)
- & SPIBUF_RXEMPTY_MASK) == 0)
- cpu_relax();
/* Determine the command to execute READ or WRITE */
if (t->tx_buf) {
@@ -770,7 +766,6 @@ static int davinci_spi_bufs_dma(struct spi_device *spi,
struct spi_transfer *t)
int int_status = 0;
int count, temp_count;
u8 conv = 1;
- u8 tmp;
u32 data1_reg_val;
struct davinci_spi_dma *davinci_spi_dma;
int word_len, data_type, ret;
@@ -794,6 +789,8 @@ static int davinci_spi_bufs_dma(struct spi_device *spi,
struct spi_transfer *t)
conv = davinci_spi->slave[spi->chip_select].bytes_per_word;
davinci_spi->count = t->len / conv;
+ data1_reg_val = ioread32(davinci_spi->base + SPIDAT1);
+
INIT_COMPLETION(davinci_spi->done);
init_completion(&davinci_spi_dma->dma_rx_completion);
@@ -820,28 +817,14 @@ static int davinci_spi_bufs_dma(struct spi_device *spi,
struct spi_transfer *t)
davinci_spi->base + SPIDELAY);
count = davinci_spi->count; /* the number of elements */
- data1_reg_val = pdata->cs_hold << SPIDAT1_CSHOLD_SHIFT;
-
- /* CS default = 0xFF */
- tmp = ~(0x1 << spi->chip_select);
-
- clear_io_bits(davinci_spi->base + SPIDEF, ~tmp);
-
- data1_reg_val |= tmp << SPIDAT1_CSNR_SHIFT;
/* disable all interrupts for dma transfers */
clear_io_bits(davinci_spi->base + SPIINT, SPIINT_MASKALL);
/* Disable SPI to write configuration bits in SPIDAT */
clear_io_bits(davinci_spi->base + SPIGCR1, SPIGCR1_SPIENA_MASK);
- iowrite32(data1_reg_val, davinci_spi->base + SPIDAT1);
/* Enable SPI */
set_io_bits(davinci_spi->base + SPIGCR1, SPIGCR1_SPIENA_MASK);
- while ((ioread32(davinci_spi->base + SPIBUF)
- & SPIBUF_RXEMPTY_MASK) == 0)
- cpu_relax();
-
-
if (t->tx_buf) {
t->tx_dma = dma_map_single(&spi->dev, (void *)t->tx_buf, count,
DMA_TO_DEVICE);
--
1.7.3.2
_______________________________________________
Davinci-linux-open-source mailing list
Davinci-linux-open-source@linux.davincidsp.com
http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
