This patch fixes two outstanding issues with the pxa2xx_spi driver:
1) Bad cast in the function u32_writer. Thanks to Henrik Bechmann
2) Adds support for per transfer changes to speed and bits per word
Signed-off-by: Stephen Street <[email protected]>
---
pxa2xx_spi.c | 82 +++++++++++++++++++++++++++++++++++++++++++++++++++++------
1 files changed, 75 insertions(+), 7 deletions(-)
--- linux-2.6.16-rc5-mm3/drivers/spi/pxa2xx_spi.c 2006-03-08 15:12:19.470303626 -0800
+++ linux-spi/drivers/spi/pxa2xx_spi.c 2006-03-08 15:12:25.732211119 -0800
@@ -120,6 +120,8 @@ struct driver_data {
dma_addr_t tx_dma;
size_t rx_map_len;
size_t tx_map_len;
+ u8 n_bytes;
+ u32 dma_width;
int cs_change;
void (*write)(struct driver_data *drv_data);
void (*read)(struct driver_data *drv_data);
@@ -139,6 +141,8 @@ struct chip_data {
u32 threshold;
u32 dma_threshold;
u8 enable_dma;
+ u8 bits_per_word;
+ u32 speed_hz;
void (*write)(struct driver_data *drv_data);
void (*read)(struct driver_data *drv_data);
void (*cs_control)(u32 command);
@@ -186,7 +190,7 @@ static void null_cs_control(u32 command)
static void null_writer(struct driver_data *drv_data)
{
void *reg = drv_data->ioaddr;
- u8 n_bytes = drv_data->cur_chip->n_bytes;
+ u8 n_bytes = drv_data->n_bytes;
while ((read_SSSR(reg) & SSSR_TNF)
&& (drv_data->tx < drv_data->tx_end)) {
@@ -198,7 +202,7 @@ static void null_writer(struct driver_da
static void null_reader(struct driver_data *drv_data)
{
void *reg = drv_data->ioaddr;
- u8 n_bytes = drv_data->cur_chip->n_bytes;
+ u8 n_bytes = drv_data->n_bytes;
while ((read_SSSR(reg) & SSSR_RNE)
&& (drv_data->rx < drv_data->rx_end)) {
@@ -256,7 +260,7 @@ static void u32_writer(struct driver_dat
while ((read_SSSR(reg) & SSSR_TNF)
&& (drv_data->tx < drv_data->tx_end)) {
- write_SSDR(*(u16 *)(drv_data->tx), reg);
+ write_SSDR(*(u32 *)(drv_data->tx), reg);
drv_data->tx += 4;
}
}
@@ -677,6 +681,10 @@ static void pump_transfers(unsigned long
struct spi_transfer *previous = NULL;
struct chip_data *chip = NULL;
void *reg = drv_data->ioaddr;
+ u32 clk_div = 0;
+ u8 bits = 0;
+ u32 speed = 0;
+ u32 cr0;
/* Get current state information */
message = drv_data->cur_msg;
@@ -713,6 +721,8 @@ static void pump_transfers(unsigned long
giveback(message, drv_data);
return;
}
+ drv_data->n_bytes = chip->n_bytes;
+ drv_data->dma_width = chip->dma_width;
drv_data->cs_control = chip->cs_control;
drv_data->tx = (void *)transfer->tx_buf;
drv_data->tx_end = drv_data->tx + transfer->len;
@@ -724,6 +734,62 @@ static void pump_transfers(unsigned long
drv_data->write = drv_data->tx ? chip->write : null_writer;
drv_data->read = drv_data->rx ? chip->read : null_reader;
drv_data->cs_change = transfer->cs_change;
+
+ /* Change speed and bit per word on a per transfer */
+ if (transfer->speed_hz || transfer->bits_per_word) {
+
+ /* Disable clock */
+ write_SSCR0(chip->cr0 & ~SSCR0_SSE, reg);
+ cr0 = chip->cr0;
+ bits = chip->bits_per_word;
+ speed = chip->speed_hz;
+
+ if (transfer->speed_hz)
+ speed = transfer->speed_hz;
+
+ if (transfer->bits_per_word)
+ bits = transfer->bits_per_word;
+
+ if (reg == SSP1_VIRT)
+ clk_div = SSP1_SerClkDiv(speed);
+ else if (reg == SSP2_VIRT)
+ clk_div = SSP2_SerClkDiv(speed);
+ else if (reg == SSP3_VIRT)
+ clk_div = SSP3_SerClkDiv(speed);
+
+ if (bits <= 8) {
+ drv_data->n_bytes = 1;
+ drv_data->dma_width = DCMD_WIDTH1;
+ drv_data->read = drv_data->read != null_reader ?
+ u8_reader : null_reader;
+ drv_data->write = drv_data->write != null_writer ?
+ u8_writer : null_writer;
+ } else if (bits <= 16) {
+ drv_data->n_bytes = 2;
+ drv_data->dma_width = DCMD_WIDTH2;
+ drv_data->read = drv_data->read != null_reader ?
+ u16_reader : null_reader;
+ drv_data->write = drv_data->write != null_writer ?
+ u16_writer : null_writer;
+ } else if (bits <= 32) {
+ drv_data->n_bytes = 4;
+ drv_data->dma_width = DCMD_WIDTH4;
+ drv_data->read = drv_data->read != null_reader ?
+ u32_reader : null_reader;
+ drv_data->write = drv_data->write != null_writer ?
+ u32_writer : null_writer;
+ }
+
+ cr0 = clk_div
+ | SSCR0_Motorola
+ | SSCR0_DataSize(bits & 0x0f)
+ | SSCR0_SSE
+ | (bits > 16 ? SSCR0_EDSS : 0);
+
+ /* Start it back up */
+ write_SSCR0(cr0, reg);
+ }
+
message->state = RUNNING_STATE;
/* Try to map dma buffer and do a dma transfer if successful */
@@ -739,13 +805,13 @@ static void pump_transfers(unsigned long
if (drv_data->rx == drv_data->null_dma_buf)
/* No target address increment */
DCMD(drv_data->rx_channel) = DCMD_FLOWSRC
- | chip->dma_width
+ | drv_data->dma_width
| chip->dma_burst_size
| drv_data->len;
else
DCMD(drv_data->rx_channel) = DCMD_INCTRGADDR
| DCMD_FLOWSRC
- | chip->dma_width
+ | drv_data->dma_width
| chip->dma_burst_size
| drv_data->len;
@@ -756,13 +822,13 @@ static void pump_transfers(unsigned long
if (drv_data->tx == drv_data->null_dma_buf)
/* No source address increment */
DCMD(drv_data->tx_channel) = DCMD_FLOWTRG
- | chip->dma_width
+ | drv_data->dma_width
| chip->dma_burst_size
| drv_data->len;
else
DCMD(drv_data->tx_channel) = DCMD_INCSRCADDR
| DCMD_FLOWTRG
- | chip->dma_width
+ | drv_data->dma_width
| chip->dma_burst_size
| drv_data->len;
@@ -943,6 +1009,7 @@ static int setup(struct spi_device *spi)
clk_div = SSP3_SerClkDiv(spi->max_speed_hz);
else
return -ENODEV;
+ chip->speed_hz = spi->max_speed_hz;
chip->cr0 = clk_div
| SSCR0_Motorola
@@ -987,6 +1054,7 @@ static int setup(struct spi_device *spi)
kfree(chip);
return -ENODEV;
}
+ chip->bits_per_word = spi->bits_per_word;
spi_set_ctldata(spi, chip);