ASoC: tegra: Add tegra-das driver

The DAS (Digital Audio Switch) is a mux/crossbar which sits between
the DACs (Digital Audio Controllers) and the DAPs (Digital Audio
Ports). Audio data may be routed between DACs and DAPs in various
combinations as required by board design/application.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 263 insertions, 0 deletions

diff --git a/sound/soc/tegra/tegra_das.c b/sound/soc/tegra/tegra_das.c
new file mode 100644
index 000000000000..796d36d5188a
--- /dev/null
+++ b/sound/soc/tegra/tegra_das.c
@@ -0,0 +1,263 @@
+/*
+ * tegra_das.c - Tegra DAS driver
+ *
+ * Author: Stephen Warren <swarren@nvidia.com>
+ * Copyright (C) 2010 - NVIDIA, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <mach/iomap.h>
+#include <sound/soc.h>
+#include "tegra_das.h"
+
+#define DRV_NAME "tegra-das"
+
+static struct tegra_das *das;
+
+static inline void tegra_das_write(u32 reg, u32 val)
+{
+	__raw_writel(val, das->regs + reg);
+}
+
+static inline u32 tegra_das_read(u32 reg)
+{
+	return __raw_readl(das->regs + reg);
+}
+
+int tegra_das_connect_dap_to_dac(int dap, int dac)
+{
+	u32 addr;
+	u32 reg;
+
+	if (!das)
+		return -ENODEV;
+
+	addr = TEGRA_DAS_DAP_CTRL_SEL +
+		(dap * TEGRA_DAS_DAP_CTRL_SEL_STRIDE);
+	reg = dac << TEGRA_DAS_DAP_CTRL_SEL_DAP_CTRL_SEL_P;
+
+	tegra_das_write(addr, reg);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(tegra_das_connect_dap_to_dac);
+
+int tegra_das_connect_dap_to_dap(int dap, int otherdap, int master,
+					int sdata1rx, int sdata2rx)
+{
+	u32 addr;
+	u32 reg;
+
+	if (!das)
+		return -ENODEV;
+
+	addr = TEGRA_DAS_DAP_CTRL_SEL +
+		(dap * TEGRA_DAS_DAP_CTRL_SEL_STRIDE);
+	reg = otherdap << TEGRA_DAS_DAP_CTRL_SEL_DAP_CTRL_SEL_P |
+		!!sdata2rx << TEGRA_DAS_DAP_CTRL_SEL_DAP_SDATA2_TX_RX_P |
+		!!sdata1rx << TEGRA_DAS_DAP_CTRL_SEL_DAP_SDATA1_TX_RX_P |
+		!!master << TEGRA_DAS_DAP_CTRL_SEL_DAP_MS_SEL_P;
+
+	tegra_das_write(addr, reg);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(tegra_das_connect_dap_to_dap);
+
+int tegra_das_connect_dac_to_dap(int dac, int dap)
+{
+	u32 addr;
+	u32 reg;
+
+	if (!das)
+		return -ENODEV;
+
+	addr = TEGRA_DAS_DAC_INPUT_DATA_CLK_SEL +
+		(dac * TEGRA_DAS_DAC_INPUT_DATA_CLK_SEL_STRIDE);
+	reg = dap << TEGRA_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_CLK_SEL_P |
+		dap << TEGRA_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_SDATA1_SEL_P |
+		dap << TEGRA_DAS_DAC_INPUT_DATA_CLK_SEL_DAC_SDATA2_SEL_P;
+
+	tegra_das_write(addr, reg);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(tegra_das_connect_dac_to_dap);
+
+#ifdef CONFIG_DEBUG_FS
+static int tegra_das_show(struct seq_file *s, void *unused)
+{
+	int i;
+	u32 addr;
+	u32 reg;
+
+	for (i = 0; i < TEGRA_DAS_DAP_CTRL_SEL_COUNT; i++) {
+		addr = TEGRA_DAS_DAP_CTRL_SEL +
+			(i * TEGRA_DAS_DAP_CTRL_SEL_STRIDE);
+		reg = tegra_das_read(addr);
+		seq_printf(s, "TEGRA_DAS_DAP_CTRL_SEL[%d] = %08x\n", i, reg);
+	}
+
+	for (i = 0; i < TEGRA_DAS_DAC_INPUT_DATA_CLK_SEL_COUNT; i++) {
+		addr = TEGRA_DAS_DAC_INPUT_DATA_CLK_SEL +
+			(i * TEGRA_DAS_DAC_INPUT_DATA_CLK_SEL_STRIDE);
+		reg = tegra_das_read(addr);
+		seq_printf(s, "TEGRA_DAS_DAC_INPUT_DATA_CLK_SEL[%d] = %08x\n",
+				 i, reg);
+	}
+
+	return 0;
+}
+
+static int tegra_das_debug_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, tegra_das_show, inode->i_private);
+}
+
+static const struct file_operations tegra_das_debug_fops = {
+	.open    = tegra_das_debug_open,
+	.read    = seq_read,
+	.llseek  = seq_lseek,
+	.release = single_release,
+};
+
+static void tegra_das_debug_add(struct tegra_das *das)
+{
+	das->debug = debugfs_create_file(DRV_NAME, S_IRUGO, asoc_debugfs_root,
+						das, &tegra_das_debug_fops);
+}
+
+static void tegra_das_debug_remove(struct tegra_das *das)
+{
+	if (das->debug)
+		debugfs_remove(das->debug);
+}
+#else
+static inline void tegra_das_debug_add(struct tegra_das *das)
+{
+}
+
+static inline void tegra_das_debug_remove(struct tegra_das *das)
+{
+}
+#endif
+
+static int __devinit tegra_das_probe(struct platform_device *pdev)
+{
+	struct resource *res, *region;
+	int ret = 0;
+
+	if (das)
+		return -ENODEV;
+
+	das = kzalloc(sizeof(struct tegra_das), GFP_KERNEL);
+	if (!das) {
+		dev_err(&pdev->dev, "Can't allocate tegra_das\n");
+		ret = -ENOMEM;
+		goto exit;
+	}
+	das->dev = &pdev->dev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "No memory resource\n");
+		ret = -ENODEV;
+		goto err_free;
+	}
+
+	region = request_mem_region(res->start, resource_size(res),
+					pdev->name);
+	if (!region) {
+		dev_err(&pdev->dev, "Memory region already claimed\n");
+		ret = -EBUSY;
+		goto err_free;
+	}
+
+	das->regs = ioremap(res->start, resource_size(res));
+	if (!das->regs) {
+		dev_err(&pdev->dev, "ioremap failed\n");
+		ret = -ENOMEM;
+		goto err_release;
+	}
+
+	tegra_das_debug_add(das);
+
+	platform_set_drvdata(pdev, das);
+
+	return 0;
+
+err_release:
+	release_mem_region(res->start, resource_size(res));
+err_free:
+	kfree(das);
+	das = 0;
+exit:
+	return ret;
+}
+
+static int __devexit tegra_das_remove(struct platform_device *pdev)
+{
+	struct resource *res;
+
+	if (!das)
+		return -ENODEV;
+
+	platform_set_drvdata(pdev, NULL);
+
+	tegra_das_debug_remove(das);
+
+	iounmap(das->regs);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	release_mem_region(res->start, resource_size(res));
+
+	kfree(das);
+	das = 0;
+
+	return 0;
+}
+
+static struct platform_driver tegra_das_driver = {
+	.probe = tegra_das_probe,
+	.remove = __devexit_p(tegra_das_remove),
+	.driver = {
+		.name = DRV_NAME,
+	},
+};
+
+static int __init tegra_das_modinit(void)
+{
+	return platform_driver_register(&tegra_das_driver);
+}
+module_init(tegra_das_modinit);
+
+static void __exit tegra_das_modexit(void)
+{
+	platform_driver_unregister(&tegra_das_driver);
+}
+module_exit(tegra_das_modexit);
+
+MODULE_AUTHOR("Stephen Warren <swarren@nvidia.com>");
+MODULE_DESCRIPTION("Tegra DAS driver");
+MODULE_LICENSE("GPL");