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path: root/drivers/spi/pxa2xx_spi.c
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Diffstat (limited to 'drivers/spi/pxa2xx_spi.c')
-rw-r--r--drivers/spi/pxa2xx_spi.c78
1 files changed, 43 insertions, 35 deletions
diff --git a/drivers/spi/pxa2xx_spi.c b/drivers/spi/pxa2xx_spi.c
index d47d3636227f..cf12f2d84be2 100644
--- a/drivers/spi/pxa2xx_spi.c
+++ b/drivers/spi/pxa2xx_spi.c
@@ -47,6 +47,10 @@ MODULE_ALIAS("platform:pxa2xx-spi");
#define MAX_BUSES 3
+#define RX_THRESH_DFLT 8
+#define TX_THRESH_DFLT 8
+#define TIMOUT_DFLT 1000
+
#define DMA_INT_MASK (DCSR_ENDINTR | DCSR_STARTINTR | DCSR_BUSERR)
#define RESET_DMA_CHANNEL (DCSR_NODESC | DMA_INT_MASK)
#define IS_DMA_ALIGNED(x) ((((u32)(x)) & 0x07) == 0)
@@ -348,21 +352,21 @@ static int map_dma_buffers(struct driver_data *drv_data)
} else
drv_data->tx_map_len = drv_data->len;
- /* Stream map the rx buffer */
- drv_data->rx_dma = dma_map_single(dev, drv_data->rx,
- drv_data->rx_map_len,
- DMA_FROM_DEVICE);
- if (dma_mapping_error(dev, drv_data->rx_dma))
- return 0;
-
- /* Stream map the tx buffer */
+ /* Stream map the tx buffer. Always do DMA_TO_DEVICE first
+ * so we flush the cache *before* invalidating it, in case
+ * the tx and rx buffers overlap.
+ */
drv_data->tx_dma = dma_map_single(dev, drv_data->tx,
- drv_data->tx_map_len,
- DMA_TO_DEVICE);
+ drv_data->tx_map_len, DMA_TO_DEVICE);
+ if (dma_mapping_error(dev, drv_data->tx_dma))
+ return 0;
- if (dma_mapping_error(dev, drv_data->tx_dma)) {
- dma_unmap_single(dev, drv_data->rx_dma,
+ /* Stream map the rx buffer */
+ drv_data->rx_dma = dma_map_single(dev, drv_data->rx,
drv_data->rx_map_len, DMA_FROM_DEVICE);
+ if (dma_mapping_error(dev, drv_data->rx_dma)) {
+ dma_unmap_single(dev, drv_data->tx_dma,
+ drv_data->tx_map_len, DMA_TO_DEVICE);
return 0;
}
@@ -1171,6 +1175,8 @@ static int setup(struct spi_device *spi)
struct driver_data *drv_data = spi_master_get_devdata(spi->master);
struct ssp_device *ssp = drv_data->ssp;
unsigned int clk_div;
+ uint tx_thres = TX_THRESH_DFLT;
+ uint rx_thres = RX_THRESH_DFLT;
if (!spi->bits_per_word)
spi->bits_per_word = 8;
@@ -1209,8 +1215,7 @@ static int setup(struct spi_device *spi)
chip->cs_control = null_cs_control;
chip->enable_dma = 0;
- chip->timeout = 1000;
- chip->threshold = SSCR1_RxTresh(1) | SSCR1_TxTresh(1);
+ chip->timeout = TIMOUT_DFLT;
chip->dma_burst_size = drv_data->master_info->enable_dma ?
DCMD_BURST8 : 0;
}
@@ -1224,22 +1229,21 @@ static int setup(struct spi_device *spi)
if (chip_info) {
if (chip_info->cs_control)
chip->cs_control = chip_info->cs_control;
-
- chip->timeout = chip_info->timeout;
-
- chip->threshold = (SSCR1_RxTresh(chip_info->rx_threshold) &
- SSCR1_RFT) |
- (SSCR1_TxTresh(chip_info->tx_threshold) &
- SSCR1_TFT);
-
- chip->enable_dma = chip_info->dma_burst_size != 0
- && drv_data->master_info->enable_dma;
+ if (chip_info->timeout)
+ chip->timeout = chip_info->timeout;
+ if (chip_info->tx_threshold)
+ tx_thres = chip_info->tx_threshold;
+ if (chip_info->rx_threshold)
+ rx_thres = chip_info->rx_threshold;
+ chip->enable_dma = drv_data->master_info->enable_dma;
chip->dma_threshold = 0;
-
if (chip_info->enable_loopback)
chip->cr1 = SSCR1_LBM;
}
+ chip->threshold = (SSCR1_RxTresh(rx_thres) & SSCR1_RFT) |
+ (SSCR1_TxTresh(tx_thres) & SSCR1_TFT);
+
/* set dma burst and threshold outside of chip_info path so that if
* chip_info goes away after setting chip->enable_dma, the
* burst and threshold can still respond to changes in bits_per_word */
@@ -1268,17 +1272,19 @@ static int setup(struct spi_device *spi)
/* NOTE: PXA25x_SSP _could_ use external clocking ... */
if (drv_data->ssp_type != PXA25x_SSP)
- dev_dbg(&spi->dev, "%d bits/word, %ld Hz, mode %d\n",
+ dev_dbg(&spi->dev, "%d bits/word, %ld Hz, mode %d, %s\n",
spi->bits_per_word,
clk_get_rate(ssp->clk)
/ (1 + ((chip->cr0 & SSCR0_SCR) >> 8)),
- spi->mode & 0x3);
+ spi->mode & 0x3,
+ chip->enable_dma ? "DMA" : "PIO");
else
- dev_dbg(&spi->dev, "%d bits/word, %ld Hz, mode %d\n",
+ dev_dbg(&spi->dev, "%d bits/word, %ld Hz, mode %d, %s\n",
spi->bits_per_word,
- clk_get_rate(ssp->clk)
+ clk_get_rate(ssp->clk) / 2
/ (1 + ((chip->cr0 & SSCR0_SCR) >> 8)),
- spi->mode & 0x3);
+ spi->mode & 0x3,
+ chip->enable_dma ? "DMA" : "PIO");
if (spi->bits_per_word <= 8) {
chip->n_bytes = 1;
@@ -1407,9 +1413,9 @@ static int __init pxa2xx_spi_probe(struct platform_device *pdev)
struct device *dev = &pdev->dev;
struct pxa2xx_spi_master *platform_info;
struct spi_master *master;
- struct driver_data *drv_data = NULL;
+ struct driver_data *drv_data;
struct ssp_device *ssp;
- int status = 0;
+ int status;
platform_info = dev->platform_data;
@@ -1422,7 +1428,7 @@ static int __init pxa2xx_spi_probe(struct platform_device *pdev)
/* Allocate master with space for drv_data and null dma buffer */
master = spi_alloc_master(dev, sizeof(struct driver_data) + 16);
if (!master) {
- dev_err(&pdev->dev, "can not alloc spi_master\n");
+ dev_err(&pdev->dev, "cannot alloc spi_master\n");
ssp_free(ssp);
return -ENOMEM;
}
@@ -1458,7 +1464,7 @@ static int __init pxa2xx_spi_probe(struct platform_device *pdev)
status = request_irq(ssp->irq, ssp_int, 0, dev->bus_id, drv_data);
if (status < 0) {
- dev_err(&pdev->dev, "can not get IRQ\n");
+ dev_err(&pdev->dev, "cannot get IRQ %d\n", ssp->irq);
goto out_error_master_alloc;
}
@@ -1498,7 +1504,9 @@ static int __init pxa2xx_spi_probe(struct platform_device *pdev)
/* Load default SSP configuration */
write_SSCR0(0, drv_data->ioaddr);
- write_SSCR1(SSCR1_RxTresh(4) | SSCR1_TxTresh(12), drv_data->ioaddr);
+ write_SSCR1(SSCR1_RxTresh(RX_THRESH_DFLT) |
+ SSCR1_TxTresh(TX_THRESH_DFLT),
+ drv_data->ioaddr);
write_SSCR0(SSCR0_SerClkDiv(2)
| SSCR0_Motorola
| SSCR0_DataSize(8),
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-29 07:48:32 +0100