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authorStephen Warren <swarren@nvidia.com>2013-11-12 00:09:35 +0400
committerStephen Warren <swarren@nvidia.com>2013-12-12 03:43:27 +0400
commit996556c92a706058cf5ce6b3ef8dacc4032a3e0d (patch)
tree8a0df4fe6165488e9f1f218cea50cc5043d1a277 /drivers/dma/tegra20-apb-dma.c
parent9aa433d2a77220fc261cb8248bb93bdd8e3944ef (diff)
downloadlinux-996556c92a706058cf5ce6b3ef8dacc4032a3e0d.tar.xz
dma: tegra: register as an OF DMA controller
Call of_dma_controller_register() so that DMA clients can look up the Tegra DMA controller using standard APIs. This requires the of_xlate() function to save off the DMA slave ID, and for tegra_dma_slave_config() not to over-write this information; once DMA client drivers are converted to dma_request_slave_channel() and DT-based lookups, they won't set this field of struct dma_slave_config anymore. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Thierry Reding <treding@nvidia.com>
Diffstat (limited to 'drivers/dma/tegra20-apb-dma.c')
-rw-r--r--drivers/dma/tegra20-apb-dma.c39
1 files changed, 36 insertions, 3 deletions
diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c
index afa5844c9346..d11bb3620f27 100644
--- a/drivers/dma/tegra20-apb-dma.c
+++ b/drivers/dma/tegra20-apb-dma.c
@@ -1,7 +1,7 @@
/*
* DMA driver for Nvidia's Tegra20 APB DMA controller.
*
- * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
+ * Copyright (c) 2012-2013, NVIDIA CORPORATION. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
@@ -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 */
+ unsigned int slave_id;
struct dma_slave_config dma_sconfig;
struct tegra_dma_channel_regs channel_reg;
};
@@ -340,6 +342,8 @@ static int tegra_dma_slave_config(struct dma_chan *dc,
}
memcpy(&tdc->dma_sconfig, sconfig, sizeof(*sconfig));
+ if (!tdc->slave_id)
+ tdc->slave_id = sconfig->slave_id;
tdc->config_init = true;
return 0;
}
@@ -942,7 +946,7 @@ 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;
@@ -1086,7 +1090,7 @@ static 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;
@@ -1206,6 +1210,25 @@ static void tegra_dma_free_chan_resources(struct dma_chan *dc)
kfree(sg_req);
}
clk_disable_unprepare(tdma->dma_clk);
+
+ tdc->slave_id = 0;
+}
+
+static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec,
+ struct of_dma *ofdma)
+{
+ struct tegra_dma *tdma = ofdma->of_dma_data;
+ struct dma_chan *chan;
+ struct tegra_dma_channel *tdc;
+
+ chan = dma_get_any_slave_channel(&tdma->dma_dev);
+ if (!chan)
+ return NULL;
+
+ tdc = to_tegra_dma_chan(chan);
+ tdc->slave_id = dma_spec->args[0];
+
+ return chan;
}
/* Tegra20 specific DMA controller information */
@@ -1383,10 +1406,20 @@ static int tegra_dma_probe(struct platform_device *pdev)
goto err_irq;
}
+ ret = of_dma_controller_register(pdev->dev.of_node,
+ tegra_dma_of_xlate, tdma);
+ if (ret < 0) {
+ dev_err(&pdev->dev,
+ "Tegra20 APB DMA OF registration failed %d\n", ret);
+ goto err_unregister_dma_dev;
+ }
+
dev_info(&pdev->dev, "Tegra20 APB DMA driver register %d channels\n",
cdata->nr_channels);
return 0;
+err_unregister_dma_dev:
+ dma_async_device_unregister(&tdma->dma_dev);
err_irq:
while (--i >= 0) {
struct tegra_dma_channel *tdc = &tdma->channels[i];