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authorOlof Johansson <olof@lixom.net>2013-12-26 20:03:29 +0100
committerOlof Johansson <olof@lixom.net>2013-12-26 20:03:29 +0100
commit770039fef4887d22b12525b62cc4ade1ca724173 (patch)
tree7408ae2a4dbe6a3b36af36976a04a968d951d6af /drivers/dma
parentMerge tag 'samsung-dt-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kge... (diff)
parentspi: tegra: checking for ERR_PTR instead of NULL (diff)
downloadlinux-770039fef4887d22b12525b62cc4ade1ca724173.tar.xz
linux-770039fef4887d22b12525b62cc4ade1ca724173.zip
Merge branch 'tegra/dma-reset-rework' into next/dt
Bringing in the tegra dma/reset framework cleanup as a base for the DT changes. * tegra/dma-reset-rework: (320 commits) spi: tegra: checking for ERR_PTR instead of NULL ASoC: tegra: update module reset list for Tegra124 clk: tegra: remove bogus PCIE_XCLK clk: tegra: remove legacy reset APIs ARM: tegra: remove legacy DMA entries from DT ARM: tegra: remove legacy clock entries from DT USB: EHCI: tegra: use reset framework Input: tegra-kbc - use reset framework serial: tegra: convert to standard DMA DT bindings serial: tegra: use reset framework spi: tegra: convert to standard DMA DT bindings spi: tegra: use reset framework staging: nvec: use reset framework i2c: tegra: use reset framework ASoC: tegra: convert to standard DMA DT bindings ASoC: tegra: allocate AHUB FIFO during probe() not startup() ASoC: tegra: call pm_runtime APIs around register accesses ASoC: tegra: use reset framework dma: tegra: register as an OF DMA controller dma: tegra: use reset framework ... Signed-off-by: Olof Johansson <olof@lixom.net>
Diffstat (limited to 'drivers/dma')
-rw-r--r--drivers/dma/dmaengine.c63
-rw-r--r--drivers/dma/mmp_pdma.c30
-rw-r--r--drivers/dma/of-dma.c15
-rw-r--r--drivers/dma/tegra20-apb-dma.c52
4 files changed, 121 insertions, 39 deletions
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index ea806bdc12ef..24095ff8a93b 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -535,11 +535,41 @@ struct dma_chan *dma_get_slave_channel(struct dma_chan *chan)
}
EXPORT_SYMBOL_GPL(dma_get_slave_channel);
+struct dma_chan *dma_get_any_slave_channel(struct dma_device *device)
+{
+ dma_cap_mask_t mask;
+ struct dma_chan *chan;
+ int err;
+
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+
+ /* lock against __dma_request_channel */
+ mutex_lock(&dma_list_mutex);
+
+ chan = private_candidate(&mask, device, NULL, NULL);
+ if (chan) {
+ err = dma_chan_get(chan);
+ if (err) {
+ pr_debug("%s: failed to get %s: (%d)\n",
+ __func__, dma_chan_name(chan), err);
+ chan = NULL;
+ }
+ }
+
+ mutex_unlock(&dma_list_mutex);
+
+ return chan;
+}
+EXPORT_SYMBOL_GPL(dma_get_any_slave_channel);
+
/**
* __dma_request_channel - try to allocate an exclusive channel
* @mask: capabilities that the channel must satisfy
* @fn: optional callback to disposition available channels
* @fn_param: opaque parameter to pass to dma_filter_fn
+ *
+ * Returns pointer to appropriate DMA channel on success or NULL.
*/
struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
dma_filter_fn fn, void *fn_param)
@@ -591,18 +621,43 @@ EXPORT_SYMBOL_GPL(__dma_request_channel);
* dma_request_slave_channel - try to allocate an exclusive slave channel
* @dev: pointer to client device structure
* @name: slave channel name
+ *
+ * Returns pointer to appropriate DMA channel on success or an error pointer.
*/
-struct dma_chan *dma_request_slave_channel(struct device *dev, const char *name)
+struct dma_chan *dma_request_slave_channel_reason(struct device *dev,
+ const char *name)
{
+ struct dma_chan *chan;
+
/* If device-tree is present get slave info from here */
if (dev->of_node)
return of_dma_request_slave_channel(dev->of_node, name);
/* If device was enumerated by ACPI get slave info from here */
- if (ACPI_HANDLE(dev))
- return acpi_dma_request_slave_chan_by_name(dev, name);
+ if (ACPI_HANDLE(dev)) {
+ chan = acpi_dma_request_slave_chan_by_name(dev, name);
+ if (chan)
+ return chan;
+ }
- return NULL;
+ return ERR_PTR(-ENODEV);
+}
+EXPORT_SYMBOL_GPL(dma_request_slave_channel_reason);
+
+/**
+ * dma_request_slave_channel - try to allocate an exclusive slave channel
+ * @dev: pointer to client device structure
+ * @name: slave channel name
+ *
+ * Returns pointer to appropriate DMA channel on success or NULL.
+ */
+struct dma_chan *dma_request_slave_channel(struct device *dev,
+ const char *name)
+{
+ struct dma_chan *ch = dma_request_slave_channel_reason(dev, name);
+ if (IS_ERR(ch))
+ return NULL;
+ return ch;
}
EXPORT_SYMBOL_GPL(dma_request_slave_channel);
diff --git a/drivers/dma/mmp_pdma.c b/drivers/dma/mmp_pdma.c
index dcb1e05149a7..2998f1bffac1 100644
--- a/drivers/dma/mmp_pdma.c
+++ b/drivers/dma/mmp_pdma.c
@@ -893,33 +893,17 @@ static struct dma_chan *mmp_pdma_dma_xlate(struct of_phandle_args *dma_spec,
struct of_dma *ofdma)
{
struct mmp_pdma_device *d = ofdma->of_dma_data;
- struct dma_chan *chan, *candidate;
+ struct dma_chan *chan;
+ struct mmp_pdma_chan *c;
-retry:
- candidate = NULL;
-
- /* walk the list of channels registered with the current instance and
- * find one that is currently unused */
- list_for_each_entry(chan, &d->device.channels, device_node)
- if (chan->client_count == 0) {
- candidate = chan;
- break;
- }
-
- if (!candidate)
+ chan = dma_get_any_slave_channel(&d->device);
+ if (!chan)
return NULL;
- /* dma_get_slave_channel will return NULL if we lost a race between
- * the lookup and the reservation */
- chan = dma_get_slave_channel(candidate);
-
- if (chan) {
- struct mmp_pdma_chan *c = to_mmp_pdma_chan(chan);
- c->drcmr = dma_spec->args[0];
- return chan;
- }
+ c = to_mmp_pdma_chan(chan);
+ c->drcmr = dma_spec->args[0];
- goto retry;
+ return chan;
}
static int mmp_pdma_probe(struct platform_device *op)
diff --git a/drivers/dma/of-dma.c b/drivers/dma/of-dma.c
index 0b88dd3d05f4..e8fe9dc455f4 100644
--- a/drivers/dma/of-dma.c
+++ b/drivers/dma/of-dma.c
@@ -143,7 +143,7 @@ static int of_dma_match_channel(struct device_node *np, const char *name,
* @np: device node to get DMA request from
* @name: name of desired channel
*
- * Returns pointer to appropriate dma channel on success or NULL on error.
+ * Returns pointer to appropriate DMA channel on success or an error pointer.
*/
struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
const char *name)
@@ -152,17 +152,18 @@ struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
struct of_dma *ofdma;
struct dma_chan *chan;
int count, i;
+ int ret_no_channel = -ENODEV;
if (!np || !name) {
pr_err("%s: not enough information provided\n", __func__);
- return NULL;
+ return ERR_PTR(-ENODEV);
}
count = of_property_count_strings(np, "dma-names");
if (count < 0) {
pr_err("%s: dma-names property of node '%s' missing or empty\n",
__func__, np->full_name);
- return NULL;
+ return ERR_PTR(-ENODEV);
}
for (i = 0; i < count; i++) {
@@ -172,10 +173,12 @@ struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
mutex_lock(&of_dma_lock);
ofdma = of_dma_find_controller(&dma_spec);
- if (ofdma)
+ if (ofdma) {
chan = ofdma->of_dma_xlate(&dma_spec, ofdma);
- else
+ } else {
+ ret_no_channel = -EPROBE_DEFER;
chan = NULL;
+ }
mutex_unlock(&of_dma_lock);
@@ -185,7 +188,7 @@ struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
return chan;
}
- return NULL;
+ return ERR_PTR(ret_no_channel);
}
/**
diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c
index 73654e33f13b..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,
@@ -29,11 +29,12 @@
#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>
+#include <linux/reset.h>
#include <linux/slab.h>
-#include <linux/clk/tegra.h>
#include "dmaengine.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;
};
@@ -208,6 +210,7 @@ struct tegra_dma {
struct dma_device dma_dev;
struct device *dev;
struct clk *dma_clk;
+ struct reset_control *rst;
spinlock_t global_lock;
void __iomem *base_addr;
const struct tegra_dma_chip_data *chip_data;
@@ -339,6 +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;
}
@@ -941,7 +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;
@@ -1085,7 +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;
@@ -1205,6 +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 */
@@ -1282,6 +1306,12 @@ static int tegra_dma_probe(struct platform_device *pdev)
return PTR_ERR(tdma->dma_clk);
}
+ tdma->rst = devm_reset_control_get(&pdev->dev, "dma");
+ if (IS_ERR(tdma->rst)) {
+ dev_err(&pdev->dev, "Error: Missing reset\n");
+ return PTR_ERR(tdma->rst);
+ }
+
spin_lock_init(&tdma->global_lock);
pm_runtime_enable(&pdev->dev);
@@ -1302,9 +1332,9 @@ static int tegra_dma_probe(struct platform_device *pdev)
}
/* Reset DMA controller */
- tegra_periph_reset_assert(tdma->dma_clk);
+ reset_control_assert(tdma->rst);
udelay(2);
- tegra_periph_reset_deassert(tdma->dma_clk);
+ reset_control_deassert(tdma->rst);
/* Enable global DMA registers */
tdma_write(tdma, TEGRA_APBDMA_GENERAL, TEGRA_APBDMA_GENERAL_ENABLE);
@@ -1376,10 +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];