/*
 *  FM Driver for Connectivity chip of Texas Instruments.
 *  This file provides interfaces to V4L2 subsystem.
 *
 *  This module registers with V4L2 subsystem as Radio
 *  data system interface (/dev/radio). During the registration,
 *  it will expose two set of function pointers to V4L2 subsystem.
 *
 *    1) File operation related API (open, close, read, write, poll...etc).
 *    2) Set of V4L2 IOCTL complaint API.
 *
 *  Copyright (C) 2010 Texas Instruments
 *
 *  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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include "fmdrv.h"
#include "fmdrv_v4l2.h"
#include "fmdrv_common.h"
#include "fmdrv_rx.h"
/* TODO: Enable when FM TX is supported */
/* #include "fmdrv_tx.h" */

#ifndef DEBUG
#ifdef pr_info
#undef pr_info
#define pr_info(fmt, arg...)
#endif
#endif

static struct video_device *gradio_dev;
static unsigned char radio_disconnected;

/* Query control */
static struct v4l2_queryctrl fmdrv_v4l2_queryctrl[] = {
	{
	 .id = V4L2_CID_AUDIO_VOLUME,
	 .type = V4L2_CTRL_TYPE_INTEGER,
	 .name = "Volume",
	 .minimum = FM_RX_VOLUME_MIN,
	 .maximum = FM_RX_VOLUME_MAX,
	 .step = 1,
	 .default_value = FM_DEFAULT_RX_VOLUME,
	 },
	{
	 .id = V4L2_CID_AUDIO_BALANCE,
	 .flags = V4L2_CTRL_FLAG_DISABLED,
	 },
	{
	 .id = V4L2_CID_AUDIO_BASS,
	 .flags = V4L2_CTRL_FLAG_DISABLED,
	 },
	{
	 .id = V4L2_CID_AUDIO_TREBLE,
	 .flags = V4L2_CTRL_FLAG_DISABLED,
	 },
	{
	 .id = V4L2_CID_AUDIO_MUTE,
	 .type = V4L2_CTRL_TYPE_BOOLEAN,
	 .name = "Mute",
	 .minimum = 0,
	 .maximum = 2,
	 .step = 1,
	 .default_value = FM_MUTE_OFF,
	 },
	{
	 .id = V4L2_CID_AUDIO_LOUDNESS,
	 .flags = V4L2_CTRL_FLAG_DISABLED,
	 },
};

/* -- V4L2 RADIO (/dev/radioX) device file operation interfaces --- */
/* Read RX RDS data */
static ssize_t fm_v4l2_fops_read(struct file *file, char __user * buf,
					size_t count, loff_t *ppos)
{
	unsigned char rds_mode;
	int ret;
	struct fmdrv_ops *fmdev;

	fmdev = video_drvdata(file);

	if (!radio_disconnected) {
		pr_err("(fmdrv): FM device is already disconnected\n");
		ret = -EIO;
		goto exit;
	}

	/* Turn on RDS mode , if it is disabled */
	ret = fm_rx_get_rds_mode(fmdev, &rds_mode);
	if (ret < 0) {
		pr_err("(fmdrv): Unable to read current rds mode");
		goto exit;
	}
	if (rds_mode == FM_RDS_DISABLE) {
		ret = fmc_set_rds_mode(fmdev, FM_RDS_ENABLE);
		if (ret < 0) {
			pr_err("(fmdrv): Failed to enable rds mode");
			goto exit;
		}
	}
	/* Copy RDS data from internal buffer to user buffer */
	ret = fmc_transfer_rds_from_internal_buff(fmdev, file, buf, count);

exit:
	return ret;
}

/* Write RDS data.
 * TODO: When FM TX support is added, use "V4L2_CID_RDS_TX_XXXX" codes,
 * instead of write operation.
 */
static ssize_t fm_v4l2_fops_write(struct file *file, const char __user * buf,
					size_t count, loff_t *ppos)
{
	struct tx_rds rds;
	int ret;
	struct fmdrv_ops *fmdev;

	ret = copy_from_user(&rds, buf, sizeof(rds));
	pr_info("(fmdrv): (%d)type: %d, text %s, af %d",
		   ret, rds.text_type, rds.text, rds.af_freq);

	fmdev = video_drvdata(file);
	/* TODO: Enable when FM TX is supported */
	/* fm_tx_set_radio_text(fmdev, rds.text, rds.text_type); */
	/* fm_tx_set_af(fmdev, rds.af_freq); */

	return 0;
}

static unsigned int fm_v4l2_fops_poll(struct file *file,
				      struct poll_table_struct *pts)
{
	int ret;
	struct fmdrv_ops *fmdev;

	fmdev = video_drvdata(file);
	ret = fmc_is_rds_data_available(fmdev, file, pts);
	if (!ret)
		return POLLIN | POLLRDNORM;
	return 0;
}

/* Handle open request for "/dev/radioX" device.
 * Start with FM RX mode as default.
 */
static int fm_v4l2_fops_open(struct file *file)
{
	int ret;
	struct fmdrv_ops *fmdev = NULL;

	/* Don't allow multiple open */
	if (radio_disconnected) {
		pr_err("(fmdrv): FM device is already opened\n");
		ret = -EBUSY;
		goto exit;
	}

	fmdev = video_drvdata(file);
	ret = fmc_prepare(fmdev);
	if (ret < 0) {
		pr_err("(fmdrv): Unable to prepare FM CORE");
		goto exit;
	}

	pr_info("(fmdrv): Load FM RX firmware..");
	ret = fmc_set_mode(fmdev, FM_MODE_RX);
	if (ret < 0) {
		pr_err("(fmdrv): Unable to load FM RX firmware");
		goto exit;
	}
	radio_disconnected = 1;

exit:
	return ret;
}

static int fm_v4l2_fops_release(struct file *file)
{
	int ret = 0;
	struct fmdrv_ops *fmdev;

	fmdev = video_drvdata(file);
	if (!radio_disconnected) {
		pr_info("(fmdrv):FM dev already closed, close called again?");
		goto exit;
	}
	ret = fmc_set_mode(fmdev, FM_MODE_OFF);
	if (ret < 0) {
		pr_err("(fmdrv): Unable to turn off the chip");
		goto exit;
	}
	ret = fmc_release(fmdev);
	if (ret < 0) {
		pr_err("(fmdrv): FM CORE release failed");
		goto exit;
	}
	radio_disconnected = 0;

exit:
	return ret;
}

/* V4L2 RADIO (/dev/radioX) device IOCTL interfaces */
static int fm_v4l2_vidioc_querycap(struct file *file, void *priv,
					struct v4l2_capability *capability)
{
	strlcpy(capability->driver, FM_DRV_NAME, sizeof(capability->driver));
	strlcpy(capability->card, FM_DRV_CARD_SHORT_NAME,
		sizeof(capability->card));
	sprintf(capability->bus_info, "UART");
	capability->version = FM_DRV_RADIO_VERSION;
	capability->capabilities = V4L2_CAP_HW_FREQ_SEEK | V4L2_CAP_TUNER |
				V4L2_CAP_RADIO | V4L2_CAP_MODULATOR |
				V4L2_CAP_AUDIO | V4L2_CAP_READWRITE |
				V4L2_CAP_RDS_CAPTURE;
	return 0;
}

static int fm_v4l2_vidioc_queryctrl(struct file *file, void *priv,
					struct v4l2_queryctrl *qc)
{
	int index;
	int ret = -EINVAL;

	if (qc->id < V4L2_CID_BASE)
		return ret;

	/* Search control ID and copy its properties */
	for (index = 0; index < NO_OF_ENTRIES_IN_ARRAY(fmdrv_v4l2_queryctrl);\
		index++) {
		if (qc->id && qc->id == fmdrv_v4l2_queryctrl[index].id) {
			memcpy(qc, &(fmdrv_v4l2_queryctrl[index]), sizeof(*qc));
			ret = 0;
			break;
		}
	}
	return ret;
}

static int fm_v4l2_vidioc_g_ctrl(struct file *file, void *priv,
					struct v4l2_control *ctrl)
{
	int ret = -EINVAL;
	unsigned short curr_vol;
	unsigned char curr_mute_mode;
	struct fmdrv_ops *fmdev;
	unsigned char chanl_spacing;

	fmdev = video_drvdata(file);

	switch (ctrl->id) {
	case V4L2_CID_AUDIO_MUTE:	/* get mute mode */
		ret = fm_rx_get_mute_mode(fmdev, &curr_mute_mode);
		if (ret < 0)
			goto exit;
		ctrl->value = curr_mute_mode;
		break;
	case V4L2_CID_AUDIO_VOLUME:	/* get volume */
		ret = fm_rx_get_volume(fmdev, &curr_vol);
		if (ret < 0)
			goto exit;
		ctrl->value = curr_vol;
		break;
	case V4L2_CID_CHANNEL_SPACING:  /* channel spacing */
		ret = fm_rx_get_chanl_spacing(fmdev, &chanl_spacing);
		ctrl->value = chanl_spacing;
		break;
	}

exit:
	return ret;
}

static int fm_v4l2_vidioc_s_ctrl(struct file *file, void *priv,
					struct v4l2_control *ctrl)
{
	int ret = -EINVAL;
	struct fmdrv_ops *fmdev;

	fmdev = video_drvdata(file);

	switch (ctrl->id) {
	case V4L2_CID_AUDIO_MUTE:	/* set mute */
		ret = fmc_set_mute_mode(fmdev, (unsigned char)ctrl->value);
		if (ret < 0)
			goto exit;
		break;
	case V4L2_CID_AUDIO_VOLUME:	/* set volume */
		ret = fm_rx_set_volume(fmdev, (unsigned short)ctrl->value);
		if (ret < 0)
			goto exit;
		break;

	case V4L2_CID_CHANNEL_SPACING:		/* channel spacing */
		ret = fm_rx_set_chanl_spacing(fmdev, (unsigned int)ctrl->value);
		break;
	}

exit:
	return ret;
}

static int fm_v4l2_vidioc_g_audio(struct file *file, void *priv,
					struct v4l2_audio *audio)
{
	memset(audio, 0, sizeof(*audio));
	audio->index = 0;
	strcpy(audio->name, "Radio");
	audio->capability = V4L2_AUDCAP_STEREO;

	return 0;
}

static int fm_v4l2_vidioc_s_audio(struct file *file, void *priv,
					struct v4l2_audio *audio)
{
	if (audio->index != 0)
		return -EINVAL;
	return 0;
}

/* Get tuner attributes. If current mode is NOT RX, set to RX */
static int fm_v4l2_vidioc_g_tuner(struct file *file, void *priv,
					struct v4l2_tuner *tuner)
{
	unsigned int bottom_frequency;
	unsigned int top_frequency;
	unsigned short stereo_mono_mode;
	unsigned short rssilvl;
	int ret = -EINVAL;
	struct fmdrv_ops *fmdev;

	if (tuner->index != 0)
		goto exit;

	fmdev = video_drvdata(file);
	if (fmdev->curr_fmmode != FM_MODE_RX) {
		ret = fmc_set_mode(fmdev, FM_MODE_RX);
		if (ret < 0) {
			pr_err("(fmdrv): Failed to set RX mode; unable to " \
					"read tuner attributes\n");
			goto exit;
		}
	}

	ret = fm_rx_get_currband_lowhigh_freq(fmdev, &bottom_frequency,
						 &top_frequency);
	if (ret < 0)
		goto exit;

	ret = fm_rx_get_stereo_mono(fmdev, &stereo_mono_mode);
	if (ret < 0)
		goto exit;

	ret = fm_rx_get_rssi_level(fmdev, &rssilvl);
	if (ret < 0)
		goto exit;

	strcpy(tuner->name, "FM");
	tuner->type = V4L2_TUNER_RADIO;
	/* Store rangelow and rangehigh freq in unit of 62.5 Hz */
	tuner->rangelow = bottom_frequency * 16;
	tuner->rangehigh = top_frequency * 16;
	tuner->rxsubchans = V4L2_TUNER_SUB_MONO | V4L2_TUNER_SUB_STEREO |
	((fmdev->rx.rds.flag == FM_RDS_ENABLE) ? V4L2_TUNER_SUB_RDS : 0);
	tuner->capability = V4L2_TUNER_CAP_STEREO | V4L2_TUNER_CAP_RDS |
				V4L2_TUNER_CAP_LOW;
	tuner->audmode = (stereo_mono_mode ?
			  V4L2_TUNER_MODE_MONO : V4L2_TUNER_MODE_STEREO);

	/* Actual rssi value lies in between -128 to +127.
	 * Convert this range from 0 to 255 by adding +128
	 */
	rssilvl += 128;

	/* Return signal strength value should be within 0 to 65535.
	 * Find out correct signal radio by multiplying (65535/255) = 257
	 */
	tuner->signal = rssilvl * 257;
	tuner->afc = 0;

exit:
	return ret;
}

/* Set tuner attributes. If current mode is NOT RX, set to RX.
 * Currently, we set only audio mode (mono/stereo) and RDS state (on/off).
 * Should we set other tuner attributes, too?
 */
static int fm_v4l2_vidioc_s_tuner(struct file *file, void *priv,
					struct v4l2_tuner *tuner)
{
	unsigned short aud_mode;
	unsigned char rds_mode;
	int ret = -EINVAL;
	struct fmdrv_ops *fmdev;

	if (tuner->index != 0)
		goto exit;

	aud_mode = (tuner->audmode == V4L2_TUNER_MODE_STEREO) ?
	    FM_STEREO_MODE : FM_MONO_MODE;
	rds_mode = (tuner->rxsubchans & V4L2_TUNER_SUB_RDS) ?
			FM_RDS_ENABLE : FM_RDS_DISABLE;

	fmdev = video_drvdata(file);
	if (fmdev->curr_fmmode != FM_MODE_RX) {
		ret = fmc_set_mode(fmdev, FM_MODE_RX);
		if (ret < 0) {
			pr_err("(fmdrv): Failed to set RX mode; unable to" \
					"write tuner attributes\n");
			goto exit;
		}
	}

	ret = fmc_set_stereo_mono(fmdev, aud_mode);
	if (ret < 0)
		goto exit;

	ret = fmc_set_rds_mode(fmdev, rds_mode);
	if (ret < 0)
		goto exit;

exit:
	return ret;
}

/* Get tuner or modulator radio frequency */
static int fm_v4l2_vidioc_g_frequency(struct file *file, void *priv,
					struct v4l2_frequency *freq)
{
	int ret;
	struct fmdrv_ops *fmdev;

	fmdev = video_drvdata(file);
	ret = fmc_get_frequency(fmdev, &freq->frequency);
	if (ret < 0)
		return ret;

	/* Convert the frequency from Khz to 62.5 Hz */
	freq->frequency = (unsigned int) freq->frequency * 16;

	return 0;
}

/* Set tuner or modulator radio frequency */
static int fm_v4l2_vidioc_s_frequency(struct file *file, void *priv,
					struct v4l2_frequency *freq)
{
	int ret;
	struct fmdrv_ops *fmdev;

	fmdev = video_drvdata(file);

	/* As tuner->capability is set to V4L2_TUNER_CAP_LOW, application sends
	* the frequency in units of 62.5 Hz but as FM chip accepts the frequency
	* in units of KHz convert the frequency from units of 62.5 Hz to KHz.
	*/
	freq->frequency = (unsigned int)(freq->frequency / 16);

	ret = fmc_set_frequency(fmdev, freq->frequency);
	if (ret < 0)
		return ret;
	return 0;
}

/* Set hardware frequency seek. If current mode is NOT RX, set it RX. */
static int fm_v4l2_vidioc_s_hw_freq_seek(struct file *file, void *priv,
					struct v4l2_hw_freq_seek *seek)
{
	int ret;
	struct fmdrv_ops *fmdev;

	fmdev = video_drvdata(file);
	if (fmdev->curr_fmmode != FM_MODE_RX) {
		ret = fmc_set_mode(fmdev, FM_MODE_RX);
		if (ret != 0) {
			pr_err("(fmdrv): Failed to set RX mode; unable to " \
					"start HW frequency seek\n");
			goto exit;
		}
	}

	ret = fm_rx_seek(fmdev, seek->seek_upward, seek->wrap_around);
	if (ret < 0)
		goto exit;

exit:
	return ret;
}

static const struct v4l2_file_operations fm_drv_fops = {
	.owner = THIS_MODULE,
	.read = fm_v4l2_fops_read,
	.write = fm_v4l2_fops_write,
	.poll = fm_v4l2_fops_poll,
	.ioctl = video_ioctl2,
	.open = fm_v4l2_fops_open,
	.release = fm_v4l2_fops_release,
};

static const struct v4l2_ioctl_ops fm_drv_ioctl_ops = {
	.vidioc_querycap = fm_v4l2_vidioc_querycap,
	.vidioc_queryctrl = fm_v4l2_vidioc_queryctrl,
	.vidioc_g_ctrl = fm_v4l2_vidioc_g_ctrl,
	.vidioc_s_ctrl = fm_v4l2_vidioc_s_ctrl,
	.vidioc_g_audio = fm_v4l2_vidioc_g_audio,
	.vidioc_s_audio = fm_v4l2_vidioc_s_audio,
	.vidioc_g_tuner = fm_v4l2_vidioc_g_tuner,
	.vidioc_s_tuner = fm_v4l2_vidioc_s_tuner,
	.vidioc_g_frequency = fm_v4l2_vidioc_g_frequency,
	.vidioc_s_frequency = fm_v4l2_vidioc_s_frequency,
	.vidioc_s_hw_freq_seek = fm_v4l2_vidioc_s_hw_freq_seek
};

/* V4L2 RADIO device parent structure */
static struct video_device fm_viddev_template = {
	.fops = &fm_drv_fops,
	.ioctl_ops = &fm_drv_ioctl_ops,
	.name = FM_DRV_NAME,
	.release = video_device_release,
};

int fm_v4l2_init_video_device(struct fmdrv_ops *fmdev, int radio_nr)
{
	int ret = -ENOMEM;

	gradio_dev = NULL;
	/* Allocate new video device */
	gradio_dev = video_device_alloc();
	if (NULL == gradio_dev) {
		pr_err("(fmdrv): Can't allocate video device");
		goto exit;
	}

	/* Setup FM driver's V4L2 properties */
	memcpy(gradio_dev, &fm_viddev_template, sizeof(fm_viddev_template));

	video_set_drvdata(gradio_dev, fmdev);

	/* Register with V4L2 subsystem as RADIO device */
	if (video_register_device(gradio_dev, VFL_TYPE_RADIO, radio_nr)) {
		video_device_release(gradio_dev);
		pr_err("(fmdrv): Could not register video device");
		goto exit;
	}

	fmdev->radio_dev = gradio_dev;
	ret = 0;

exit:
	return ret;
}

void *fm_v4l2_deinit_video_device(void)
{
	struct fmdrv_ops *fmdev;

	fmdev = video_get_drvdata(gradio_dev);
	/* Unregister RADIO device from V4L2 subsystem */
	video_unregister_device(gradio_dev);

	return fmdev;
}