V4L/DVB (3661): Add wm8739 stereo audio ADC i2c driver

Add support for the Wolfson Microelectronics WM8739
stereo A/D converter from the ivtv driver.
Many thanks to Takahiro Adachi for writing the original driver.

Signed-off-by: Takahiro Adachi <[e-mail]>
Signed-off-by: Hans Verkuil <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/video/Kconfig

···
 	  module will be called cs53l32a
 
 config VIDEO_WM8775
-	tristate "Wolfson Microelectronics WM8775 audio ADC"
+	tristate "Wolfson Microelectronics WM8775 audio ADC with input mixer"
 	depends on VIDEO_DEV && I2C && EXPERIMENTAL
 	---help---
-	  Support for the Wolfson Microelectronics WM8775
-	  high performance stereo A/D Converter.
+	  Support for the Wolfson Microelectronics WM8775 high
+	  performance stereo A/D Converter with a 4 channel input mixer.
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called wm8775
+
+config VIDEO_WM8739
+	tristate "Wolfson Microelectronics WM8739 stereo audio ADC"
+	depends on VIDEO_DEV && I2C && EXPERIMENTAL
+	---help---
+	  Support for the Wolfson Microelectronics WM8739
+	  stereo A/D Converter.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called wm8739
 
 source "drivers/media/video/cx25840/Kconfig"
 

drivers/media/video/Makefile

···
 obj-$(CONFIG_VIDEO_MSP3400) += msp3400.o
 obj-$(CONFIG_VIDEO_CS53L32A) += cs53l32a.o
 obj-$(CONFIG_VIDEO_WM8775) += wm8775.o
+obj-$(CONFIG_VIDEO_WM8739) += wm8739.o
 obj-$(CONFIG_VIDEO_OVCAMCHIP) += ovcamchip/
 obj-$(CONFIG_VIDEO_CPIA2) += cpia2/
 obj-$(CONFIG_VIDEO_MXB) += saa7111.o tda9840.o tea6415c.o tea6420.o mxb.o

drivers/media/video/wm8739.c

···
+/*
+ * wm8739
+ *
+ * Copyright (C) 2005 T. Adachi <[e-mail]>
+ *
+ * Copyright (C) 2005 Hans Verkuil <[e-mail]>
+ * - Cleanup
+ *
+ * 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/i2c-id.h>
+#include <linux/videodev.h>
+#include <media/v4l2-common.h>
+
+MODULE_DESCRIPTION("wm8739 driver");
+MODULE_AUTHOR("T. Adachi, Hans Verkuil");
+MODULE_LICENSE("GPL");
+
+static int debug = 0;
+static unsigned short normal_i2c[] = { 0x34 >> 1, 0x36 >> 1, I2C_CLIENT_END };
+
+module_param(debug, int, 0644);
+
+MODULE_PARM_DESC(debug, "Debug level (0-1)");
+
+
+I2C_CLIENT_INSMOD;
+
+/* ------------------------------------------------------------------------ */
+
+enum {
+	R0 = 0, R1,
+	R5 = 5, R6, R7, R8, R9, R15 = 15,
+	TOT_REGS
+};
+
+struct wm8739_state {
+	u32 clock_freq;
+	u8 muted;
+	u16 volume;
+	u16 balance;
+	u8 vol_l; 		/* +12dB to -34.5dB 1.5dB step (5bit) def:0dB */
+	u8 vol_r; 		/* +12dB to -34.5dB 1.5dB step (5bit) def:0dB */
+};
+
+/* ------------------------------------------------------------------------ */
+
+static int wm8739_write(struct i2c_client *client, int reg, u16 val)
+{
+	int i;
+
+	if (reg < 0 || reg >= TOT_REGS) {
+		v4l_err(client, "Invalid register R%d\n", reg);
+		return -1;
+	}
+
+	v4l_dbg(1, debug, client, "write: %02x %02x\n", reg, val);
+
+	for (i = 0; i < 3; i++) {
+		if (i2c_smbus_write_byte_data(client, (reg << 1) |
+					(val >> 8), val & 0xff) == 0) {
+			return 0;
+		}
+	}
+	v4l_err(client, "I2C: cannot write %03x to register R%d\n", val, reg);
+	return -1;
+}
+
+/* write regs to set audio volume etc */
+static void wm8739_set_audio(struct i2c_client *client)
+{
+	struct wm8739_state *state = i2c_get_clientdata(client);
+	u16 mute = state->muted ? 0x80 : 0;
+
+	/* Volume setting: bits 0-4, 0x1f = 12 dB, 0x00 = -34.5 dB
+	 * Default setting: 0x17 = 0 dB
+	 */
+	wm8739_write(client, R0, (state->vol_l & 0x1f) | mute);
+	wm8739_write(client, R1, (state->vol_r & 0x1f) | mute);
+}
+
+static int wm8739_get_ctrl(struct i2c_client *client, struct v4l2_control *ctrl)
+{
+	struct wm8739_state *state = i2c_get_clientdata(client);
+
+	switch (ctrl->id) {
+	case V4L2_CID_AUDIO_MUTE:
+		ctrl->value = state->muted;
+		break;
+
+	case V4L2_CID_AUDIO_VOLUME:
+		ctrl->value = state->volume;
+		break;
+
+	case V4L2_CID_AUDIO_BALANCE:
+		ctrl->value = state->balance;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int wm8739_set_ctrl(struct i2c_client *client, struct v4l2_control *ctrl)
+{
+	struct wm8739_state *state = i2c_get_clientdata(client);
+	unsigned int work_l, work_r;
+
+	switch (ctrl->id) {
+	case V4L2_CID_AUDIO_MUTE:
+		state->muted = ctrl->value;
+		break;
+
+	case V4L2_CID_AUDIO_VOLUME:
+		state->volume = ctrl->value;
+		break;
+
+	case V4L2_CID_AUDIO_BALANCE:
+		state->balance = ctrl->value;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	/* normalize ( 65535 to 0 -> 31 to 0 (12dB to -34.5dB) ) */
+	work_l = (min(65536 - state->balance, 32768) * state->volume) / 32768;
+	work_r = (min(state->balance, (u16)32768) * state->volume) / 32768;
+
+	state->vol_l = (long)work_l * 31 / 65535;
+	state->vol_r = (long)work_r * 31 / 65535;
+
+	/* set audio volume etc. */
+	wm8739_set_audio(client);
+	return 0;
+}
+
+/* ------------------------------------------------------------------------ */
+
+static struct v4l2_queryctrl wm8739_qctrl[] = {
+	{
+		.id            = V4L2_CID_AUDIO_VOLUME,
+		.name          = "Volume",
+		.minimum       = 0,
+		.maximum       = 65535,
+		.step          = 65535/100,
+		.default_value = 58880,
+		.flags         = 0,
+		.type          = V4L2_CTRL_TYPE_INTEGER,
+	},{
+		.id            = V4L2_CID_AUDIO_MUTE,
+		.name          = "Mute",
+		.minimum       = 0,
+		.maximum       = 1,
+		.step          = 1,
+		.default_value = 1,
+		.flags         = 0,
+		.type          = V4L2_CTRL_TYPE_BOOLEAN,
+	},{
+		.id            = V4L2_CID_AUDIO_BALANCE,
+		.name          = "Balance",
+		.minimum       = 0,
+		.maximum       = 65535,
+		.step          = 65535/100,
+		.default_value = 32768,
+		.flags         = 0,
+		.type          = V4L2_CTRL_TYPE_INTEGER,
+	}
+};
+
+/* ------------------------------------------------------------------------ */
+
+static int wm8739_command(struct i2c_client *client, unsigned int cmd, void *arg)
+{
+	struct wm8739_state *state = i2c_get_clientdata(client);
+
+	switch (cmd) {
+	case VIDIOC_INT_AUDIO_CLOCK_FREQ:
+	{
+		u32 audiofreq = *(u32 *)arg;
+
+		state->clock_freq = audiofreq;
+		wm8739_write(client, R9, 0x000);	/* de-activate */
+		switch (audiofreq) {
+		case 44100:
+			wm8739_write(client, R8, 0x020); /* 256fps, fs=44.1k     */
+			break;
+		case 48000:
+			wm8739_write(client, R8, 0x000); /* 256fps, fs=48k       */
+			break;
+		case 32000:
+			wm8739_write(client, R8, 0x018); /* 256fps, fs=32k       */
+			break;
+		default:
+			break;
+		}
+		wm8739_write(client, R9, 0x001);	/* activate */
+		break;
+	}
+
+	case VIDIOC_G_CTRL:
+		return wm8739_get_ctrl(client, arg);
+
+	case VIDIOC_S_CTRL:
+		return wm8739_set_ctrl(client, arg);
+
+	case VIDIOC_QUERYCTRL:
+	{
+		struct v4l2_queryctrl *qc = arg;
+		int i;
+
+		for (i = 0; i < ARRAY_SIZE(wm8739_qctrl); i++)
+			if (qc->id && qc->id == wm8739_qctrl[i].id) {
+				memcpy(qc, &wm8739_qctrl[i], sizeof(*qc));
+				return 0;
+			}
+		return -EINVAL;
+	}
+
+	case VIDIOC_LOG_STATUS:
+		v4l_info(client, "Frequency: %u Hz\n", state->clock_freq);
+		v4l_info(client, "Volume L:  %02x%s\n", state->vol_l & 0x1f,
+				state->muted ? " (muted)" : "");
+		v4l_info(client, "Volume R:  %02x%s\n", state->vol_r & 0x1f,
+				state->muted ? " (muted)" : "");
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/* ------------------------------------------------------------------------ */
+
+/* i2c implementation */
+
+static struct i2c_driver i2c_driver;
+
+static int wm8739_attach(struct i2c_adapter *adapter, int address, int kind)
+{
+	struct i2c_client *client;
+	struct wm8739_state *state;
+
+	/* Check if the adapter supports the needed features */
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+		return 0;
+
+	client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL);
+	if (client == NULL)
+		return -ENOMEM;
+
+	client->addr = address;
+	client->adapter = adapter;
+	client->driver = &i2c_driver;
+	snprintf(client->name, sizeof(client->name) - 1, "wm8739");
+
+	v4l_info(client, "chip found @ 0x%x (%s)\n", address << 1, adapter->name);
+
+	state = kmalloc(sizeof(struct wm8739_state), GFP_KERNEL);
+	if (state == NULL) {
+		kfree(client);
+		return -ENOMEM;
+	}
+	state->vol_l = 0x17; /* 0dB */
+	state->vol_r = 0x17; /* 0dB */
+	state->muted = 0;
+	state->balance = 32768;
+	/* normalize (12dB(31) to -34.5dB(0) [0dB(23)] -> 65535 to 0) */
+	state->volume = ((long)state->vol_l + 1) * 65535 / 31;
+	state->clock_freq = 48000;
+	i2c_set_clientdata(client, state);
+
+	/* initialize wm8739 */
+	wm8739_write(client, R15, 0x00); /* reset */
+	wm8739_write(client, R5, 0x000); /* filter setting, high path, offet clear */
+	wm8739_write(client, R6, 0x000); /* ADC, OSC, Power Off mode Disable */
+	wm8739_write(client, R7, 0x049); /* Digital Audio interface format */
+					 /* Enable Master mode */
+					 /* 24 bit, MSB first/left justified */
+	wm8739_write(client, R8, 0x000); /* sampling control */
+					 /* normal, 256fs, 48KHz sampling rate */
+	wm8739_write(client, R9, 0x001); /* activate */
+	wm8739_set_audio(client); 	 /* set volume/mute */
+
+	i2c_attach_client(client);
+
+	return 0;
+}
+
+static int wm8739_probe(struct i2c_adapter *adapter)
+{
+	if (adapter->class & I2C_CLASS_TV_ANALOG)
+		return i2c_probe(adapter, &addr_data, wm8739_attach);
+	return 0;
+}
+
+static int wm8739_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 = {
+	.driver = {
+		.name = "wm8739",
+	},
+	.id = I2C_DRIVERID_WM8739,
+	.attach_adapter = wm8739_probe,
+	.detach_client  = wm8739_detach,
+	.command = wm8739_command,
+};
+
+
+static int __init wm8739_init_module(void)
+{
+	return i2c_add_driver(&i2c_driver);
+}
+
+static void __exit wm8739_cleanup_module(void)
+{
+	i2c_del_driver(&i2c_driver);
+}
+
+module_init(wm8739_init_module);
+module_exit(wm8739_cleanup_module);