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-rw-r--r--drivers/media/i2c/tea6420.c140
1 files changed, 140 insertions, 0 deletions
diff --git a/drivers/media/i2c/tea6420.c b/drivers/media/i2c/tea6420.c
new file mode 100644
index 0000000000..63f23784bb
--- /dev/null
+++ b/drivers/media/i2c/tea6420.c
@@ -0,0 +1,140 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+ /*
+ tea6420 - i2c-driver for the tea6420 by SGS Thomson
+
+ Copyright (C) 1998-2003 Michael Hunold <michael@mihu.de>
+ Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>
+
+ The tea6420 is a bus controlled audio-matrix with 5 stereo inputs,
+ 4 stereo outputs and gain control for each output.
+ It is cascadable, i.e. it can be found at the addresses 0x98
+ and 0x9a on the i2c-bus.
+
+ For detailed information download the specifications directly
+ from SGS Thomson at http://www.st.com
+
+ */
+
+
+#include <linux/module.h>
+#include <linux/ioctl.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <media/v4l2-device.h>
+#include "tea6420.h"
+
+MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
+MODULE_DESCRIPTION("tea6420 driver");
+MODULE_LICENSE("GPL");
+
+static int debug;
+module_param(debug, int, 0644);
+
+MODULE_PARM_DESC(debug, "Debug level (0-1)");
+
+
+/* make a connection between the input 'i' and the output 'o'
+ with gain 'g' (note: i = 6 means 'mute') */
+static int tea6420_s_routing(struct v4l2_subdev *sd,
+ u32 i, u32 o, u32 config)
+{
+ struct i2c_client *client = v4l2_get_subdevdata(sd);
+ int g = (o >> 4) & 0xf;
+ u8 byte;
+ int ret;
+
+ o &= 0xf;
+ v4l2_dbg(1, debug, sd, "i=%d, o=%d, g=%d\n", i, o, g);
+
+ /* check if the parameters are valid */
+ if (i < 1 || i > 6 || o < 1 || o > 4 || g < 0 || g > 6 || g % 2 != 0)
+ return -EINVAL;
+
+ byte = ((o - 1) << 5);
+ byte |= (i - 1);
+
+ /* to understand this, have a look at the tea6420-specs (p.5) */
+ switch (g) {
+ case 0:
+ byte |= (3 << 3);
+ break;
+ case 2:
+ byte |= (2 << 3);
+ break;
+ case 4:
+ byte |= (1 << 3);
+ break;
+ case 6:
+ break;
+ }
+
+ ret = i2c_smbus_write_byte(client, byte);
+ if (ret) {
+ v4l2_dbg(1, debug, sd,
+ "i2c_smbus_write_byte() failed, ret:%d\n", ret);
+ return -EIO;
+ }
+ return 0;
+}
+
+/* ----------------------------------------------------------------------- */
+
+static const struct v4l2_subdev_audio_ops tea6420_audio_ops = {
+ .s_routing = tea6420_s_routing,
+};
+
+static const struct v4l2_subdev_ops tea6420_ops = {
+ .audio = &tea6420_audio_ops,
+};
+
+static int tea6420_probe(struct i2c_client *client)
+{
+ struct v4l2_subdev *sd;
+ int err, i;
+
+ /* let's see whether this adapter can support what we need */
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE))
+ return -EIO;
+
+ v4l_info(client, "chip found @ 0x%x (%s)\n",
+ client->addr << 1, client->adapter->name);
+
+ sd = devm_kzalloc(&client->dev, sizeof(*sd), GFP_KERNEL);
+ if (sd == NULL)
+ return -ENOMEM;
+ v4l2_i2c_subdev_init(sd, client, &tea6420_ops);
+
+ /* set initial values: set "mute"-input to all outputs at gain 0 */
+ err = 0;
+ for (i = 1; i < 5; i++)
+ err += tea6420_s_routing(sd, 6, i, 0);
+ if (err) {
+ v4l_dbg(1, debug, client, "could not initialize tea6420\n");
+ return -ENODEV;
+ }
+ return 0;
+}
+
+static void tea6420_remove(struct i2c_client *client)
+{
+ struct v4l2_subdev *sd = i2c_get_clientdata(client);
+
+ v4l2_device_unregister_subdev(sd);
+}
+
+static const struct i2c_device_id tea6420_id[] = {
+ { "tea6420", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, tea6420_id);
+
+static struct i2c_driver tea6420_driver = {
+ .driver = {
+ .name = "tea6420",
+ },
+ .probe = tea6420_probe,
+ .remove = tea6420_remove,
+ .id_table = tea6420_id,
+};
+
+module_i2c_driver(tea6420_driver);