dma: cirrus: add DT support for Cirrus EP93xx

- find register range from the device tree
- get clocks, interrupts from device tree

Co-developed-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Signed-off-by: Nikita Shubin <nikita.shubin@maquefel.me>

diff --git a/drivers/dma/ep93xx_dma.c b/drivers/dma/ep93xx_dma.c
index 5338a94f1a69f00be71d7371d3dc991b5ff82319..501004835368c9670d25d1ea43b5c35cab02776a 100644 (file)
--- a/drivers/dma/ep93xx_dma.c
+++ b/drivers/dma/ep93xx_dma.c
@@ -20,6 +20,7 @@
 #include <linux/dmaengine.h>
 #include <linux/module.h>
 #include <linux/mod_devicetable.h>
+#include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 
@@ -104,6 +105,11 @@
 #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,
@@ -213,7 +219,7 @@ struct ep93xx_dma_engine {
 #define INTERRUPT_NEXT_BUFFER  2
 
        size_t                  num_channels;
-       struct ep93xx_dma_chan  channels[];
+       struct ep93xx_dma_chan  *channels;
 };
 
 static inline struct device *chan2dev(struct ep93xx_dma_chan *edmac)
@@ -875,9 +881,11 @@ static int ep93xx_dma_alloc_chan_resources(struct dma_chan *chan)
        if (!edmac->edma->m2m) {
                if (!data)
                        return -EINVAL;
+
                if (data->port < EP93XX_DMA_I2S1 ||
                    data->port > EP93XX_DMA_IRDA)
                        return -EINVAL;
+
                if (data->direction != ep93xx_dma_chan_direction(chan))
                        return -EINVAL;
        } else {
@@ -1315,20 +1323,88 @@ 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 const struct of_device_id ep93xx_dma_of_ids[] = {
+       { .compatible = "cirrus,ep9301-dma-m2p", .data = (const void *)M2P_DMA },
+       { .compatible = "cirrus,ep9301-dma-m2m", .data = (const void *)M2M_DMA },
+       {},
+};
+MODULE_DEVICE_TABLE(of, ep93xx_dma_of_ids);
+
+static int ep93xx_dma_of_probe(struct platform_device *pdev,
+                       struct ep93xx_dma_engine *edma)
+{
+       struct device_node *np = pdev->dev.of_node;
+       const struct of_device_id *match = of_match_node(ep93xx_dma_of_ids, pdev->dev.of_node);
+       struct dma_device *dma_dev = &edma->dma_dev;
+       int num_channels;
+       int i, ret;
+
+       ret = of_property_read_u32(np, "dma-channels", &num_channels);
+       if (ret) {
+               dev_err(&pdev->dev, "failed to read dma-channels\n");
+               return ret;
+       }
+
+       edma->channels = devm_kzalloc(&pdev->dev,
+                                     num_channels * sizeof(struct ep93xx_dma_chan),
+                                     GFP_KERNEL);
+       if (!edma->channels)
+               return -ENOMEM;
+
+       edma->num_channels = num_channels;
+       edma->m2m = match->data;
+
+       INIT_LIST_HEAD(&dma_dev->channels);
+       for (i = 0; i < 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 0;
+}
+#else
+static int ep93xx_dma_of_probe(struct platform_device *pdev,
+                       struct ep93xx_dma_engine *edma)
+{
+       return -EINVAL;
+}
+#endif
+
+static int ep93xx_init_from_pdata(struct platform_device *pdev,
+                                 struct ep93xx_dma_engine *edma)
 {
        struct ep93xx_dma_platform_data *pdata = dev_get_platdata(&pdev->dev);
-       struct ep93xx_dma_engine *edma;
-       struct dma_device *dma_dev;
-       size_t edma_size;
-       int ret, i;
+       struct dma_device *dma_dev = &edma->dma_dev;
+       int i;
 
-       edma_size = pdata->num_channels * sizeof(struct ep93xx_dma_chan);
-       edma = kzalloc(sizeof(*edma) + edma_size, GFP_KERNEL);
-       if (!edma)
+       edma->channels = devm_kzalloc(&pdev->dev,
+                                     pdata->num_channels * sizeof(struct ep93xx_dma_chan),
+                                     GFP_KERNEL);
+       if (!edma->channels)
                return -ENOMEM;
 
-       dma_dev = &edma->dma_dev;
        edma->m2m = platform_get_device_id(pdev)->driver_data;
        edma->num_channels = pdata->num_channels;
 
@@ -1359,6 +1435,27 @@ static int __init ep93xx_dma_probe(struct platform_device *pdev)
                              &dma_dev->channels);
        }
 
+       return 0;
+}
+
+static int __init ep93xx_dma_probe(struct platform_device *pdev)
+{
+       struct ep93xx_dma_engine *edma;
+       struct dma_device *dma_dev;
+       int ret, i;
+
+       edma = devm_kzalloc(&pdev->dev, sizeof(*edma), GFP_KERNEL);
+
+       if (platform_get_device_id(pdev))
+               ret = ep93xx_init_from_pdata(pdev, edma);
+       else
+               ret = ep93xx_dma_of_probe(pdev, edma);
+
+       if (ret)
+               return ret;
+
+       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);
@@ -1415,10 +1512,12 @@ static const struct platform_device_id ep93xx_dma_driver_ids[] = {
        { "ep93xx-dma-m2m", 1 },
        { },
 };
+MODULE_DEVICE_TABLE(of, 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,
 };

diff --git a/include/linux/platform_data/dma-ep93xx.h b/include/linux/platform_data/dma-ep93xx.h
index eb9805bb3fe8a82372a9c1a8d3f9802753680da6..d485e3c21a3a764795cae92f8ae2f3df49f229a7 100644 (file)
--- a/include/linux/platform_data/dma-ep93xx.h
+++ b/include/linux/platform_data/dma-ep93xx.h
@@ -70,6 +70,9 @@ 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");
 }