Update tegra20-apbdma driver to adopt generic DMA device tree bindings.
It calls of_dma_controller_register() with of_dma_simple_xlate to get
the generic DMA device tree helper support. The #dma-cells for apbdma
must be 1, which is slave ID.
The existing nvidia,dma-request-selector still works there, and the
support will be removed after all clients get converted to generic DMA
device tree helper.
Signed-off-by: Richard Zhao <rizhao@xxxxxxxxxx>
---
drivers/dma/tegra20-apb-dma.c | 46 +++++++++++++++++++++++++++++++++++++++++--
1 file changed, 44 insertions(+), 2 deletions(-)
diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c
index f137914..0e12f78 100644
--- a/drivers/dma/tegra20-apb-dma.c
+++ b/drivers/dma/tegra20-apb-dma.c
@@ -29,6 +29,7 @@
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
+#include <linux/of_dma.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/pm_runtime.h>
@@ -199,6 +200,7 @@ struct tegra_dma_channel {
void *callback_param;
/* Channel-slave specific configuration */
+ int slave_id;
struct dma_slave_config dma_sconfig;
struct tegra_dma_channel_regs channel_reg;
};
@@ -219,6 +221,8 @@ struct tegra_dma {
struct tegra_dma_channel channels[0];
};
+static struct platform_driver tegra_dmac_driver;
+
static inline void tdma_write(struct tegra_dma *tdma, u32 reg, u32 val)
{
writel(val, tdma->base_addr + reg);
@@ -339,6 +343,14 @@ static int tegra_dma_slave_config(struct dma_chan *dc,
}
memcpy(&tdc->dma_sconfig, sconfig, sizeof(*sconfig));
+
+ /* If we didn't get slave_id from DT when request channel, use the one
+ * passed here.
+ * It makes compatible with legacy nvidia,dma-request-selector.
+ */
+ if (tdc->slave_id == -EINVAL)
+ tdc->slave_id = sconfig->slave_id;
+
tdc->config_init = true;
return 0;
}
@@ -943,7 +955,7 @@ static struct dma_async_tx_descriptor *tegra_dma_prep_slave_sg(
ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32;
csr |= TEGRA_APBDMA_CSR_ONCE | TEGRA_APBDMA_CSR_FLOW;
- csr |= tdc->dma_sconfig.slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT;
+ csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT;
if (flags & DMA_PREP_INTERRUPT)
csr |= TEGRA_APBDMA_CSR_IE_EOC;
@@ -1087,7 +1099,7 @@ struct dma_async_tx_descriptor *tegra_dma_prep_dma_cyclic(
csr |= TEGRA_APBDMA_CSR_FLOW;
if (flags & DMA_PREP_INTERRUPT)
csr |= TEGRA_APBDMA_CSR_IE_EOC;
- csr |= tdc->dma_sconfig.slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT;
+ csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT;
apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1;
@@ -1209,6 +1221,23 @@ static void tegra_dma_free_chan_resources(struct dma_chan *dc)
clk_disable_unprepare(tdma->dma_clk);
}
+static bool tegra_dma_filter_fn(struct dma_chan *dc, void *param)
+{
+ if (dc->device->dev->driver == &tegra_dmac_driver.driver) {
+ struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
+ unsigned req = *(unsigned *)param;
+
+ tdc->slave_id = req;
+
+ return true;
+ }
+ return false;
+}
+
+static struct of_dma_filter_info tegra_dma_info = {
+ .filter_fn = tegra_dma_filter_fn,
+};
+
/* Tegra20 specific DMA controller information */
static const struct tegra_dma_chip_data tegra20_dma_chip_data = {
.nr_channels = 16,
@@ -1345,6 +1374,7 @@ static int tegra_dma_probe(struct platform_device *pdev)
&tdma->dma_dev.channels);
tdc->tdma = tdma;
tdc->id = i;
+ tdc->slave_id = -EINVAL;
tasklet_init(&tdc->tasklet, tegra_dma_tasklet,
(unsigned long)tdc);
@@ -1378,10 +1408,21 @@ static int tegra_dma_probe(struct platform_device *pdev)
goto err_irq;
}
+ ret = of_dma_controller_register(pdev->dev.of_node,
+ of_dma_simple_xlate, &tegra_dma_info);
+ if (ret) {
+ dev_err(&pdev->dev,
+ "Tegra20 APB DMA controller registration failed %d\n",
+ ret);
+ goto err_of_dma;
+ }
+
dev_info(&pdev->dev, "Tegra20 APB DMA driver register %d channels\n",
cdata->nr_channels);
return 0;
+err_of_dma:
+ dma_async_device_unregister(&tdma->dma_dev);
err_irq:
while (--i >= 0) {
struct tegra_dma_channel *tdc = &tdma->channels[i];
@@ -1401,6 +1442,7 @@ static int tegra_dma_remove(struct platform_device *pdev)
int i;
struct tegra_dma_channel *tdc;
+ of_dma_controller_free(pdev->dev.of_node);
dma_async_device_unregister(&tdma->dma_dev);
for (i = 0; i < tdma->chip_data->nr_channels; ++i) {
--
1.8.1.5
--
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