[PATCH] v4l: 771: the wm8775 is a wolfson microelectronics 24 bit 96khz adc with 4

- Support for Wolfson Microelectronics wm8775 audio processor
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@brturbo.com.br>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

drivers/media/video/wm8775.c

+/*
+ * wm8775 - driver version 0.0.1
+ *
+ * Copyright (C) 2004 Ulf Eklund <ivtv at eklund.to>
+ *
+ * Based on saa7115 driver
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/ioctl.h>
+#include <asm/uaccess.h>
+#include <linux/i2c.h>
+#include <linux/videodev.h>
+#include <media/audiochip.h>
+#include <media/id.h>
+
+MODULE_DESCRIPTION("wm8775 driver");
+MODULE_AUTHOR("Ulf Eklund");
+MODULE_LICENSE("GPL");
+
+#define wm8775_err(fmt, arg...) do { \
+	printk(KERN_ERR "%s %d-%04x: " fmt, client->driver->name, \
+               i2c_adapter_id(client->adapter), client->addr , ## arg); } while (0)
+#define wm8775_info(fmt, arg...) do { \
+	printk(KERN_INFO "%s %d-%04x: " fmt, client->driver->name, \
+               i2c_adapter_id(client->adapter), client->addr , ## arg); } while (0)
+
+
+static unsigned short normal_i2c[] = { 0x36 >> 1, I2C_CLIENT_END };
+
+
+I2C_CLIENT_INSMOD;
+
+/* ----------------------------------------------------------------------- */
+
+enum {
+	R7 = 7, R11 = 11,
+	R12, R13, R14, R15, R16, R17, R18, R19, R20, R21, R23 = 23,
+	TOT_REGS
+};
+
+struct wm8775_state {
+	u8 input;		/* Last selected input (0-0xf) */
+	u8 muted;
+};
+
+static int wm8775_write(struct i2c_client *client, int reg, u16 val)
+{
+	int i;
+
+	if (reg < 0 || reg >= TOT_REGS) {
+		wm8775_err("Invalid register R%d\n", reg);
+		return -1;
+	}
+
+	for (i = 0; i < 3; i++) {
+		if (i2c_smbus_write_byte_data(client, (reg << 1) |
+					(val >> 8), val & 0xff) == 0) {
+			return 0;
+		}
+	}
+	wm8775_err("I2C: cannot write %03x to register R%d\n", val, reg);
+	return -1;
+}
+
+static int wm8775_command(struct i2c_client *client, unsigned int cmd,
+			  void *arg)
+{
+	struct wm8775_state *state = i2c_get_clientdata(client);
+	int *input = arg;
+
+	switch (cmd) {
+	case AUDC_SET_INPUT:
+		wm8775_write(client, R21, 0x0c0);
+		wm8775_write(client, R14, 0x1d4);
+		wm8775_write(client, R15, 0x1d4);
+
+		if (*input == AUDIO_RADIO) {
+			wm8775_write(client, R21, 0x108);
+			state->input = 8;
+			state->muted = 0;
+			break;
+		}
+		if (*input == AUDIO_MUTE) {
+			state->muted = 1;
+			break;
+		}
+		if (*input == AUDIO_UNMUTE) {
+			wm8775_write(client, R21, 0x100 + state->input);
+			state->muted = 0;
+			break;
+		}
+		/* All other inputs... */
+		wm8775_write(client, R21, 0x102);
+		state->input = 2;
+		state->muted = 0;
+		break;
+
+
+	case VIDIOCSFREQ:
+		/* If I remove this, then it can happen that I have no
+		   sound the first time I tune from static to a valid channel.
+		   It's difficult to reproduce and is almost certainly related
+		   to the zero cross detect circuit. */
+		wm8775_write(client, R21, 0x0c0);
+		wm8775_write(client, R14, 0x1d4);
+		wm8775_write(client, R15, 0x1d4);
+		wm8775_write(client, R21, 0x100 + state->input);
+		break;
+
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+/* ----------------------------------------------------------------------- */
+
+/* i2c implementation */
+
+/*
+ * Generic i2c probe
+ * concerning the addresses: i2c wants 7 bit (without the r/w bit), so '>>1'
+ */
+
+static struct i2c_driver i2c_driver;
+
+static int wm8775_attach(struct i2c_adapter *adapter, int address, int kind)
+{
+	struct i2c_client *client;
+	struct wm8775_state *state;
+
+	/* Check if the adapter supports the needed features */
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+		return 0;
+
+	client = kmalloc(sizeof(struct i2c_client), GFP_KERNEL);
+	if (client == 0)
+		return -ENOMEM;
+
+	memset(client, 0, sizeof(struct i2c_client));
+	client->addr = address;
+	client->adapter = adapter;
+	client->driver = &i2c_driver;
+	client->flags = I2C_CLIENT_ALLOW_USE;
+	snprintf(client->name, sizeof(client->name) - 1, "wm8775");
+
+	wm8775_info("chip found @ 0x%x (%s)\n", address << 1, adapter->name);
+
+	state = kmalloc(sizeof(struct wm8775_state), GFP_KERNEL);
+	if (state == NULL) {
+		kfree(client);
+		return -ENOMEM;
+	}
+	state->input = 2;
+	state->muted = 0;
+	i2c_set_clientdata(client, state);
+
+	/* initialize wm8775 */
+	wm8775_write(client, R23, 0x000);	/* RESET */
+	wm8775_write(client, R7, 0x000);	/* Disable zero cross detect timeout */
+	wm8775_write(client, R11, 0x021);	/* Left justified, 24-bit mode */
+	wm8775_write(client, R12, 0x102);	/* Master mode, clock ratio 256fs */
+	wm8775_write(client, R13, 0x000);	/* Powered up */
+	wm8775_write(client, R14, 0x1d4);	/* ADC gain +2.5dB, enable zero cross */
+	wm8775_write(client, R15, 0x1d4);	/* ADC gain +2.5dB, enable zero cross */
+	wm8775_write(client, R16, 0x1bf);	/* ALC Stereo, ALC target level -1dB FS */
+	/* max gain +8dB */
+	wm8775_write(client, R17, 0x185);	/* Enable gain control, use zero cross */
+	/* detection, ALC hold time 42.6 ms */
+	wm8775_write(client, R18, 0x0a2);	/* ALC gain ramp up delay 34 s, */
+	/* ALC gain ramp down delay 33 ms */
+	wm8775_write(client, R19, 0x005);	/* Enable noise gate, threshold -72dBfs */
+	wm8775_write(client, R20, 0x07a);	/* Transient window 4ms, lower PGA gain */
+	/* limit -1dB */
+	wm8775_write(client, R21, 0x102);	/* LRBOTH = 1, use input 2. */
+	i2c_attach_client(client);
+
+	return 0;
+}
+
+static int wm8775_probe(struct i2c_adapter *adapter)
+{
+#ifdef I2C_CLASS_TV_ANALOG
+	if (adapter->class & I2C_CLASS_TV_ANALOG)
+		return i2c_probe(adapter, &addr_data, wm8775_attach);
+#else
+	switch (adapter->id) {
+	case I2C_HW_B_BT848:
+		return i2c_probe(adapter, &addr_data, tda9887_attach);
+	}
+#endif /* I2C_CLASS_TV_ANALOG */
+
+	return 0;
+}
+
+static int wm8775_detach(struct i2c_client *client)
+{
+	int err;
+
+	err = i2c_detach_client(client);
+	if (err) {
+		return err;
+	}
+	kfree(client);
+
+	return 0;
+}
+
+/* ----------------------------------------------------------------------- */
+
+/* i2c implementation */
+static struct i2c_driver i2c_driver = {
+	.name = "wm8775",
+
+	.id = I2C_DRIVERID_WM8775,
+	.flags = I2C_DF_NOTIFY,
+
+	.attach_adapter = wm8775_probe,
+	.detach_client = wm8775_detach,
+	.command = wm8775_command,
+	.owner = THIS_MODULE,
+};
+
+
+static int __init wm8775_init_module(void)
+{
+	return i2c_add_driver(&i2c_driver);
+}
+
+static void __exit wm8775_cleanup_module(void)
+{
+	i2c_del_driver(&i2c_driver);
+}
+
+module_init(wm8775_init_module);
+module_exit(wm8775_cleanup_module);