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spi: davinci: Use dma_request_chan() for requesting DMA channel

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With the new dma_request_chan() the client driver does not need to look for
the DMA resource and it does not need to pass filter_fn anymore.
By switching to the new API the driver can now support deferred probing
against DMA.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Peter Ujfalusi 2016-04-29 16:10:22 +03:00 committed by Mark Brown
parent f55532a0c0
commit fe5fd25409
1 changed files with 23 additions and 51 deletions
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74
drivers/spi/spi-davinci.c
View file

@ -23,7 +23,6 @@
#include <linux/clk.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/edma.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_gpio.h>
@ -33,8 +32,6 @@
#include <linux/platform_data/spi-davinci.h>
#define SPI_NO_RESOURCE ((resource_size_t)-1)
#define CS_DEFAULT 0xFF
#define SPIFMT_PHASE_MASK BIT(16)
@ -130,8 +127,6 @@ struct davinci_spi {
struct dma_chan *dma_rx;
struct dma_chan *dma_tx;
int dma_rx_chnum;
int dma_tx_chnum;
struct davinci_spi_platform_data pdata;
@ -797,35 +792,19 @@ static irqreturn_t davinci_spi_irq(s32 irq, void *data)
static int davinci_spi_request_dma(struct davinci_spi *dspi)
{
dma_cap_mask_t mask;
struct device *sdev = dspi->bitbang.master->dev.parent;
int r;
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
dspi->dma_rx = dma_request_chan(sdev, "rx");
if (IS_ERR(dspi->dma_rx))
return PTR_ERR(dspi->dma_rx);
dspi->dma_rx = dma_request_channel(mask, edma_filter_fn,
&dspi->dma_rx_chnum);
if (!dspi->dma_rx) {
dev_err(sdev, "request RX DMA channel failed\n");
r = -ENODEV;
goto rx_dma_failed;
}
dspi->dma_tx = dma_request_channel(mask, edma_filter_fn,
&dspi->dma_tx_chnum);
if (!dspi->dma_tx) {
dev_err(sdev, "request TX DMA channel failed\n");
r = -ENODEV;
goto tx_dma_failed;
dspi->dma_tx = dma_request_chan(sdev, "tx");
if (IS_ERR(dspi->dma_tx)) {
dma_release_channel(dspi->dma_rx);
return PTR_ERR(dspi->dma_tx);
}
return 0;
tx_dma_failed:
dma_release_channel(dspi->dma_rx);
rx_dma_failed:
return r;
}
#if defined(CONFIG_OF)
@ -936,8 +915,6 @@ static int davinci_spi_probe(struct platform_device *pdev)
struct davinci_spi *dspi;
struct davinci_spi_platform_data *pdata;
struct resource *r;
resource_size_t dma_rx_chan = SPI_NO_RESOURCE;
resource_size_t dma_tx_chan = SPI_NO_RESOURCE;
int ret = 0;
u32 spipc0;
@ -1044,27 +1021,15 @@ static int davinci_spi_probe(struct platform_device *pdev)
}
}
r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
if (r)
dma_rx_chan = r->start;
r = platform_get_resource(pdev, IORESOURCE_DMA, 1);
if (r)
dma_tx_chan = r->start;
dspi->bitbang.txrx_bufs = davinci_spi_bufs;
if (dma_rx_chan != SPI_NO_RESOURCE &&
dma_tx_chan != SPI_NO_RESOURCE) {
dspi->dma_rx_chnum = dma_rx_chan;
dspi->dma_tx_chnum = dma_tx_chan;
ret = davinci_spi_request_dma(dspi);
if (ret)
goto free_clk;
dev_info(&pdev->dev, "DMA: supported\n");
dev_info(&pdev->dev, "DMA: RX channel: %pa, TX channel: %pa, event queue: %d\n",
&dma_rx_chan, &dma_tx_chan,
pdata->dma_event_q);
ret = davinci_spi_request_dma(dspi);
if (ret == -EPROBE_DEFER) {
goto free_clk;
} else if (ret) {
dev_info(&pdev->dev, "DMA is not supported (%d)\n", ret);
dspi->dma_rx = NULL;
dspi->dma_tx = NULL;
}
dspi->get_rx = davinci_spi_rx_buf_u8;
@ -1102,8 +1067,10 @@ static int davinci_spi_probe(struct platform_device *pdev)
return ret;
free_dma:
dma_release_channel(dspi->dma_rx);
dma_release_channel(dspi->dma_tx);
if (dspi->dma_rx) {
dma_release_channel(dspi->dma_rx);
dma_release_channel(dspi->dma_tx);
}
free_clk:
clk_disable_unprepare(dspi->clk);
free_master:
@ -1134,6 +1101,11 @@ static int davinci_spi_remove(struct platform_device *pdev)
clk_disable_unprepare(dspi->clk);
spi_master_put(master);
if (dspi->dma_rx) {
dma_release_channel(dspi->dma_rx);
dma_release_channel(dspi->dma_tx);
}
return 0;
}