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From 32530970c34f0e8e447fd9a7f8991df6f04b8ccc Mon Sep 17 00:00:00 2001
From: Matthias Reichl <hias@horus.com>
Date: Sun, 11 Oct 2015 16:44:05 +0200
Subject: [PATCH] bcm2835-i2s: get base address for DMA from devicetree
Code copied from spi-bcm2835. Get physical address from devicetree
instead of using hardcoded constant.
Signed-off-by: Matthias Reichl <hias@horus.com>
---
sound/soc/bcm/bcm2835-i2s.c | 20 ++++++++++++--------
1 file changed, 12 insertions(+), 8 deletions(-)
--- a/sound/soc/bcm/bcm2835-i2s.c
+++ b/sound/soc/bcm/bcm2835-i2s.c
@@ -38,6 +38,7 @@
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/clk.h>
+#include <linux/of_address.h>
#include <sound/core.h>
#include <sound/pcm.h>
@@ -158,10 +159,6 @@ static const unsigned int bcm2835_clk_fr
#define BCM2835_I2S_INT_RXR BIT(1)
#define BCM2835_I2S_INT_TXW BIT(0)
-/* I2S DMA interface */
-/* FIXME: Needs IOMMU support */
-#define BCM2835_VCMMU_SHIFT (0x7E000000 - 0x20000000)
-
/* General device struct */
struct bcm2835_i2s_dev {
struct device *dev;
@@ -791,6 +788,15 @@ static int bcm2835_i2s_probe(struct plat
int ret;
struct regmap *regmap[2];
struct resource *mem[2];
+ const __be32 *addr;
+ dma_addr_t dma_reg_base;
+
+ addr = of_get_address(pdev->dev.of_node, 0, NULL, NULL);
+ if (!addr) {
+ dev_err(&pdev->dev, "could not get DMA-register address\n");
+ return -ENODEV;
+ }
+ dma_reg_base = be32_to_cpup(addr);
/* Request both ioareas */
for (i = 0; i <= 1; i++) {
@@ -817,12 +823,10 @@ static int bcm2835_i2s_probe(struct plat
/* Set the DMA address */
dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK].addr =
- (dma_addr_t)mem[0]->start + BCM2835_I2S_FIFO_A_REG
- + BCM2835_VCMMU_SHIFT;
+ dma_reg_base + BCM2835_I2S_FIFO_A_REG;
dev->dma_data[SNDRV_PCM_STREAM_CAPTURE].addr =
- (dma_addr_t)mem[0]->start + BCM2835_I2S_FIFO_A_REG
- + BCM2835_VCMMU_SHIFT;
+ dma_reg_base + BCM2835_I2S_FIFO_A_REG;
/* Set the bus width */
dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK].addr_width =
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