[PATCH v3 22/42] dma: cirrus: add DT support for Cirrus EP93xx
Nikita Shubin via B4 Relay
devnull+nikita.shubin.maquefel.me at kernel.org
Thu Jul 20 04:29:22 PDT 2023
From: Nikita Shubin <nikita.shubin at maquefel.me>
- drop subsys_initcall code
- add OF ID match table with data
- add of_probe for device tree
Co-developed-by: Alexander Sverdlin <alexander.sverdlin at gmail.com>
Signed-off-by: Alexander Sverdlin <alexander.sverdlin at gmail.com>
Signed-off-by: Nikita Shubin <nikita.shubin at maquefel.me>
---
drivers/dma/ep93xx_dma.c | 131 ++++++++++++++++++++++++++++---
include/linux/platform_data/dma-ep93xx.h | 4 +
2 files changed, 122 insertions(+), 13 deletions(-)
diff --git a/drivers/dma/ep93xx_dma.c b/drivers/dma/ep93xx_dma.c
index 5338a94f1a69..1b38180e2a2c 100644
--- a/drivers/dma/ep93xx_dma.c
+++ b/drivers/dma/ep93xx_dma.c
@@ -20,6 +20,8 @@
#include <linux/dmaengine.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
+#include <linux/of_device.h>
+#include <linux/overflow.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
@@ -104,6 +106,11 @@
#define DMA_MAX_CHAN_BYTES 0xffff
#define DMA_MAX_CHAN_DESCRIPTORS 32
+enum ep93xx_dma_type {
+ M2P_DMA,
+ M2M_DMA,
+};
+
struct ep93xx_dma_engine;
static int ep93xx_dma_slave_config_write(struct dma_chan *chan,
enum dma_transfer_direction dir,
@@ -216,6 +223,11 @@ struct ep93xx_dma_engine {
struct ep93xx_dma_chan channels[];
};
+struct ep93xx_edma_data {
+ u32 id;
+ size_t num_channels;
+};
+
static inline struct device *chan2dev(struct ep93xx_dma_chan *edmac)
{
return &edmac->chan.dev->device;
@@ -1315,22 +1327,82 @@ static void ep93xx_dma_issue_pending(struct dma_chan *chan)
ep93xx_dma_advance_work(to_ep93xx_dma_chan(chan));
}
-static int __init ep93xx_dma_probe(struct platform_device *pdev)
+
+#ifdef CONFIG_OF
+static struct ep93xx_dma_engine *ep93xx_dma_of_probe(struct platform_device *pdev)
{
- struct ep93xx_dma_platform_data *pdata = dev_get_platdata(&pdev->dev);
+ struct device_node *np = pdev->dev.of_node;
+ const struct ep93xx_edma_data *data;
struct ep93xx_dma_engine *edma;
struct dma_device *dma_dev;
- size_t edma_size;
- int ret, i;
+ int i;
+
+ data = of_device_get_match_data(&pdev->dev);
+ if (!data)
+ return ERR_PTR(dev_err_probe(&pdev->dev, -ENODEV, "No device match found\n"));
- edma_size = pdata->num_channels * sizeof(struct ep93xx_dma_chan);
- edma = kzalloc(sizeof(*edma) + edma_size, GFP_KERNEL);
+ edma = devm_kzalloc(&pdev->dev,
+ struct_size(edma, channels, data->num_channels),
+ GFP_KERNEL);
if (!edma)
- return -ENOMEM;
+ return ERR_PTR(-ENOMEM);
+ edma->m2m = data->id;
+ edma->num_channels = data->num_channels;
dma_dev = &edma->dma_dev;
+
+ INIT_LIST_HEAD(&dma_dev->channels);
+ for (i = 0; i < edma->num_channels; i++) {
+ struct ep93xx_dma_chan *edmac = &edma->channels[i];
+
+ edmac->chan.device = dma_dev;
+ edmac->regs = devm_platform_ioremap_resource(pdev, i);
+ edmac->irq = platform_get_irq(pdev, i);
+ edmac->edma = edma;
+
+ edmac->clk = of_clk_get(np, i);
+
+ if (IS_ERR(edmac->clk)) {
+ dev_warn(&pdev->dev, "failed to get clock\n");
+ continue;
+ }
+
+ spin_lock_init(&edmac->lock);
+ INIT_LIST_HEAD(&edmac->active);
+ INIT_LIST_HEAD(&edmac->queue);
+ INIT_LIST_HEAD(&edmac->free_list);
+ tasklet_setup(&edmac->tasklet, ep93xx_dma_tasklet);
+
+ list_add_tail(&edmac->chan.device_node,
+ &dma_dev->channels);
+ }
+
+ return edma;
+}
+#else
+static int ep93xx_dma_of_probe(struct platform_device *pdev,
+ struct ep93xx_dma_engine *edma)
+{
+ return -EINVAL;
+}
+#endif
+
+static struct ep93xx_dma_engine *ep93xx_init_from_pdata(struct platform_device *pdev)
+{
+ struct ep93xx_dma_platform_data *pdata = dev_get_platdata(&pdev->dev);
+ struct ep93xx_dma_engine *edma;
+ struct dma_device *dma_dev;
+ int i;
+
+ edma = devm_kzalloc(&pdev->dev,
+ struct_size(edma, channels, pdata->num_channels),
+ GFP_KERNEL);
+ if (!edma)
+ return ERR_PTR(-ENOMEM);
+
edma->m2m = platform_get_device_id(pdev)->driver_data;
edma->num_channels = pdata->num_channels;
+ dma_dev = &edma->dma_dev;
INIT_LIST_HEAD(&dma_dev->channels);
for (i = 0; i < pdata->num_channels; i++) {
@@ -1359,6 +1431,25 @@ static int __init ep93xx_dma_probe(struct platform_device *pdev)
&dma_dev->channels);
}
+ return edma;
+}
+
+static int ep93xx_dma_probe(struct platform_device *pdev)
+{
+ struct ep93xx_dma_engine *edma;
+ struct dma_device *dma_dev;
+ int ret, i;
+
+ if (platform_get_device_id(pdev))
+ edma = ep93xx_init_from_pdata(pdev);
+ else
+ edma = ep93xx_dma_of_probe(pdev);
+
+ if (!edma)
+ return PTR_ERR(edma);
+
+ dma_dev = &edma->dma_dev;
+
dma_cap_zero(dma_dev->cap_mask);
dma_cap_set(DMA_SLAVE, dma_dev->cap_mask);
dma_cap_set(DMA_CYCLIC, dma_dev->cap_mask);
@@ -1410,6 +1501,23 @@ static int __init ep93xx_dma_probe(struct platform_device *pdev)
return ret;
}
+static const struct ep93xx_edma_data edma_m2p = {
+ .id = M2P_DMA,
+ .num_channels = 10,
+};
+
+static const struct ep93xx_edma_data edma_m2m = {
+ .id = M2M_DMA,
+ .num_channels = 2,
+};
+
+static const struct of_device_id ep93xx_dma_of_ids[] = {
+ { .compatible = "cirrus,ep9301-dma-m2p", .data = &edma_m2p },
+ { .compatible = "cirrus,ep9301-dma-m2m", .data = &edma_m2m },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, ep93xx_dma_of_ids);
+
static const struct platform_device_id ep93xx_dma_driver_ids[] = {
{ "ep93xx-dma-m2p", 0 },
{ "ep93xx-dma-m2m", 1 },
@@ -1419,15 +1527,12 @@ static const struct platform_device_id ep93xx_dma_driver_ids[] = {
static struct platform_driver ep93xx_dma_driver = {
.driver = {
.name = "ep93xx-dma",
+ .of_match_table = ep93xx_dma_of_ids,
},
.id_table = ep93xx_dma_driver_ids,
+ .probe = ep93xx_dma_probe,
};
-static int __init ep93xx_dma_module_init(void)
-{
- return platform_driver_probe(&ep93xx_dma_driver, ep93xx_dma_probe);
-}
-subsys_initcall(ep93xx_dma_module_init);
-
+module_platform_driver(ep93xx_dma_driver);
MODULE_AUTHOR("Mika Westerberg <mika.westerberg at iki.fi>");
MODULE_DESCRIPTION("EP93xx DMA driver");
diff --git a/include/linux/platform_data/dma-ep93xx.h b/include/linux/platform_data/dma-ep93xx.h
index 54b41d1468ef..b5b4bd5f9a9e 100644
--- a/include/linux/platform_data/dma-ep93xx.h
+++ b/include/linux/platform_data/dma-ep93xx.h
@@ -5,6 +5,7 @@
#include <linux/types.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
+#include <linux/of.h>
#include <dt-bindings/dma/cirrus,ep93xx-dma.h>
/**
@@ -51,6 +52,9 @@ struct ep93xx_dma_platform_data {
static inline bool ep93xx_dma_chan_is_m2p(struct dma_chan *chan)
{
+ if (of_device_is_compatible(dev_of_node(chan->device->dev), "cirrus,ep9301-dma-m2p"))
+ return true;
+
return !strcmp(dev_name(chan->device->dev), "ep93xx-dma-m2p");
}
--
2.39.2
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