dw_dmac: add ACPI support

Since we have proper ACPI DMA helpers implemented, the driver may use it. This
patch introduces custom filter function together with acpi_device_id table.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

2 files changed, 50 insertions, 19 deletions

diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c
index e33dc3bdbdba..2e5deaa82b60 100644
--- a/drivers/dma/dw_dmac.c
+++ b/drivers/dma/dw_dmac.c
@@ -25,6 +25,8 @@
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
+#include <linux/acpi.h>
+#include <linux/acpi_dma.h>
 
 #include "dw_dmac_regs.h"
 #include "dmaengine.h"
@@ -983,13 +985,6 @@ static inline void convert_burst(u32 *maxburst)
                 *maxburst = 0;
 }
 
-static inline void convert_slave_id(struct dw_dma_chan *dwc)
-{
-        struct dw_dma *dw = to_dw_dma(dwc->chan.device);
-
-        dwc->dma_sconfig.slave_id -= dw->request_line_base;
-}
-
 static int
 set_runtime_config(struct dma_chan *chan, struct dma_slave_config *sconfig)
 {
@@ -1008,7 +1003,6 @@ set_runtime_config(struct dma_chan *chan, struct dma_slave_config *sconfig)
 
         convert_burst(&dwc->dma_sconfig.src_maxburst);
         convert_burst(&dwc->dma_sconfig.dst_maxburst);
-        convert_slave_id(dwc);
 
         return 0;
 }
@@ -1284,6 +1278,46 @@ static struct dma_chan *dw_dma_of_xlate(struct of_phandle_args *dma_spec,
         return dma_request_channel(cap, dw_dma_of_filter, &fargs);
 }
 
+#ifdef CONFIG_ACPI
+static bool dw_dma_acpi_filter(struct dma_chan *chan, void *param)
+{
+        struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+        struct acpi_dma_spec *dma_spec = param;
+
+        if (chan->device->dev != dma_spec->dev ||
+            chan->chan_id != dma_spec->chan_id)
+                return false;
+
+        dwc->request_line = dma_spec->slave_id;
+        dwc->src_master = dwc_get_sms(NULL);
+        dwc->dst_master = dwc_get_dms(NULL);
+
+        return true;
+}
+
+static void dw_dma_acpi_controller_register(struct dw_dma *dw)
+{
+        struct device *dev = dw->dma.dev;
+        struct acpi_dma_filter_info *info;
+        int ret;
+
+        info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
+        if (!info)
+                return;
+
+        dma_cap_zero(info->dma_cap);
+        dma_cap_set(DMA_SLAVE, info->dma_cap);
+        info->filter_fn = dw_dma_acpi_filter;
+
+        ret = devm_acpi_dma_controller_register(dev, acpi_dma_simple_xlate,
+                                                info);
+        if (ret)
+                dev_err(dev, "could not register acpi_dma_controller\n");
+}
+#else /* !CONFIG_ACPI */
+static inline void dw_dma_acpi_controller_register(struct dw_dma *dw) {}
+#endif /* !CONFIG_ACPI */
+
 /* --------------------- Cyclic DMA API extensions -------------------- */
 
 /**
@@ -1620,7 +1654,6 @@ dw_dma_parse_dt(struct platform_device *pdev)
 
 static int dw_probe(struct platform_device *pdev)
 {
-        const struct platform_device_id *match;
         struct dw_dma_platform_data *pdata;
         struct resource         *io;
         struct dw_dma           *dw;
@@ -1704,11 +1737,6 @@ static int dw_probe(struct platform_device *pdev)
                 memcpy(dw->data_width, pdata->data_width, 4);
         }
 
-        /* Get the base request line if set */
-        match = platform_get_device_id(pdev);
-        if (match)
-                dw->request_line_base = (unsigned int)match->driver_data;
-
         /* Calculate all channel mask before DMA setup */
         dw->all_chan_mask = (1 << nr_channels) - 1;
 
@@ -1833,6 +1861,9 @@ static int dw_probe(struct platform_device *pdev)
                                 "could not register of_dma_controller\n");
         }
 
+        if (ACPI_HANDLE(&pdev->dev))
+                dw_dma_acpi_controller_register(dw);
+
         return 0;
 }
 
@@ -1904,11 +1935,12 @@ static const struct of_device_id dw_dma_of_id_table[] = {
 MODULE_DEVICE_TABLE(of, dw_dma_of_id_table);
 #endif
 
-static const struct platform_device_id dw_dma_ids[] = {
-        /* Name,        Request Line Base */
-        { "INTL9C60",   (kernel_ulong_t)16 },
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id dw_dma_acpi_id_table[] = {
+        { "INTL9C60", 0 },
         { }
 };
+#endif
 
 static struct platform_driver dw_driver = {
         .probe          = dw_probe,
@@ -1918,8 +1950,8 @@ static struct platform_driver dw_driver = {
                 .name   = "dw_dmac",
                 .pm     = &dw_dev_pm_ops,
                 .of_match_table = of_match_ptr(dw_dma_of_id_table),
+                .acpi_match_table = ACPI_PTR(dw_dma_acpi_id_table),
         },
-        .id_table       = dw_dma_ids,
 };
 
 static int __init dw_init(void)
diff --git a/drivers/dma/dw_dmac_regs.h b/drivers/dma/dw_dmac_regs.h
index 9b0e12e85e31..9d417200bd57 100644
--- a/drivers/dma/dw_dmac_regs.h
+++ b/drivers/dma/dw_dmac_regs.h
@@ -250,7 +250,6 @@ struct dw_dma {
         /* hardware configuration */
         unsigned char           nr_masters;
         unsigned char           data_width[4];
-        unsigned int            request_line_base;
 
         struct dw_dma_chan      chan[0];
 };