/*
 *   v4l2 driver for TEA5777 Philips AM/FM radio tuner chips
 *
 *	Copyright (c) 2012 Hans de Goede <hdegoede@redhat.com>
 *
 *   Based on the ALSA driver for TEA5757/5759 Philips AM/FM radio tuner chips:
 *
 *	Copyright (c) 2004 Jaroslav Kysela <perex@perex.cz>
 *
 *   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., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

#include <linux/delay.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <media/v4l2-device.h>
#include <media/v4l2-dev.h>
#include <media/v4l2-fh.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-event.h>
#include <asm/div64.h>
#include "radio-tea5777.h"

MODULE_AUTHOR("Hans de Goede <perex@perex.cz>");
MODULE_DESCRIPTION("Routines for control of TEA5777 Philips AM/FM radio tuner chips");
MODULE_LICENSE("GPL");

/* Fixed FM only band for now, will implement multi-band support when the
   VIDIOC_ENUM_FREQ_BANDS API is upstream */
#define TEA5777_FM_RANGELOW		(76000 * 16)
#define TEA5777_FM_RANGEHIGH		(108000 * 16)

#define TEA5777_FM_IF			150 /* kHz */
#define TEA5777_FM_FREQ_STEP		50 /* kHz */

/* Write reg, common bits */
#define TEA5777_W_MUTE_MASK		(1LL << 47)
#define TEA5777_W_MUTE_SHIFT		47
#define TEA5777_W_AM_FM_MASK		(1LL << 46)
#define TEA5777_W_AM_FM_SHIFT		46
#define TEA5777_W_STB_MASK		(1LL << 45)
#define TEA5777_W_STB_SHIFT		45

#define TEA5777_W_IFCE_MASK		(1LL << 29)
#define TEA5777_W_IFCE_SHIFT		29
#define TEA5777_W_IFW_MASK		(1LL << 28)
#define TEA5777_W_IFW_SHIFT		28
#define TEA5777_W_HILO_MASK		(1LL << 27)
#define TEA5777_W_HILO_SHIFT		27
#define TEA5777_W_DBUS_MASK		(1LL << 26)
#define TEA5777_W_DBUS_SHIFT		26

#define TEA5777_W_INTEXT_MASK		(1LL << 24)
#define TEA5777_W_INTEXT_SHIFT		24
#define TEA5777_W_P1_MASK		(1LL << 23)
#define TEA5777_W_P1_SHIFT		23
#define TEA5777_W_P0_MASK		(1LL << 22)
#define TEA5777_W_P0_SHIFT		22
#define TEA5777_W_PEN1_MASK		(1LL << 21)
#define TEA5777_W_PEN1_SHIFT		21
#define TEA5777_W_PEN0_MASK		(1LL << 20)
#define TEA5777_W_PEN0_SHIFT		20

#define TEA5777_W_CHP0_MASK		(1LL << 18)
#define TEA5777_W_CHP0_SHIFT		18
#define TEA5777_W_DEEM_MASK		(1LL << 17)
#define TEA5777_W_DEEM_SHIFT		17

#define TEA5777_W_SEARCH_MASK		(1LL << 7)
#define TEA5777_W_SEARCH_SHIFT		7
#define TEA5777_W_PROGBLIM_MASK		(1LL << 6)
#define TEA5777_W_PROGBLIM_SHIFT	6
#define TEA5777_W_UPDWN_MASK		(1LL << 5)
#define TEA5777_W_UPDWN_SHIFT		5
#define TEA5777_W_SLEV_MASK		(3LL << 3)
#define TEA5777_W_SLEV_SHIFT		3

/* Write reg, FM specific bits */
#define TEA5777_W_FM_PLL_MASK		(0x1fffLL << 32)
#define TEA5777_W_FM_PLL_SHIFT		32
#define TEA5777_W_FM_FREF_MASK		(0x03LL << 30)
#define TEA5777_W_FM_FREF_SHIFT		30
#define TEA5777_W_FM_FREF_VALUE		0 /* 50 kHz tune steps, 150 kHz IF */

#define TEA5777_W_FM_FORCEMONO_MASK	(1LL << 15)
#define TEA5777_W_FM_FORCEMONO_SHIFT	15
#define TEA5777_W_FM_SDSOFF_MASK	(1LL << 14)
#define TEA5777_W_FM_SDSOFF_SHIFT	14
#define TEA5777_W_FM_DOFF_MASK		(1LL << 13)
#define TEA5777_W_FM_DOFF_SHIFT		13

#define TEA5777_W_FM_STEP_MASK		(3LL << 1)
#define TEA5777_W_FM_STEP_SHIFT		1

/* Write reg, AM specific bits */
#define TEA5777_W_AM_PLL_MASK		(0x7ffLL << 34)
#define TEA5777_W_AM_PLL_SHIFT		34
#define TEA5777_W_AM_AGCRF_MASK		(1LL << 33)
#define TEA5777_W_AM_AGCRF_SHIFT	33
#define TEA5777_W_AM_AGCIF_MASK		(1LL << 32)
#define TEA5777_W_AM_AGCIF_SHIFT	32
#define TEA5777_W_AM_MWLW_MASK		(1LL << 31)
#define TEA5777_W_AM_MWLW_SHIFT		31
#define TEA5777_W_AM_LNA_MASK		(1LL << 30)
#define TEA5777_W_AM_LNA_SHIFT		30

#define TEA5777_W_AM_PEAK_MASK		(1LL << 25)
#define TEA5777_W_AM_PEAK_SHIFT		25

#define TEA5777_W_AM_RFB_MASK		(1LL << 16)
#define TEA5777_W_AM_RFB_SHIFT		16
#define TEA5777_W_AM_CALLIGN_MASK	(1LL << 15)
#define TEA5777_W_AM_CALLIGN_SHIFT	15
#define TEA5777_W_AM_CBANK_MASK		(0x7fLL << 8)
#define TEA5777_W_AM_CBANK_SHIFT	8

#define TEA5777_W_AM_DELAY_MASK		(1LL << 2)
#define TEA5777_W_AM_DELAY_SHIFT	2
#define TEA5777_W_AM_STEP_MASK		(1LL << 1)
#define TEA5777_W_AM_STEP_SHIFT		1

/* Read reg, common bits */
#define TEA5777_R_LEVEL_MASK		(0x0f << 17)
#define TEA5777_R_LEVEL_SHIFT		17
#define TEA5777_R_SFOUND_MASK		(0x01 << 16)
#define TEA5777_R_SFOUND_SHIFT		16
#define TEA5777_R_BLIM_MASK		(0x01 << 15)
#define TEA5777_R_BLIM_SHIFT		15

/* Read reg, FM specific bits */
#define TEA5777_R_FM_STEREO_MASK	(0x01 << 21)
#define TEA5777_R_FM_STEREO_SHIFT	21
#define TEA5777_R_FM_PLL_MASK		0x1fff
#define TEA5777_R_FM_PLL_SHIFT		0

static u32 tea5777_freq_to_v4l2_freq(struct radio_tea5777 *tea, u32 freq)
{
	return (freq * TEA5777_FM_FREQ_STEP + TEA5777_FM_IF) * 16;
}

static int radio_tea5777_set_freq(struct radio_tea5777 *tea)
{
	u64 freq;
	int res;

	freq = clamp_t(u32, tea->freq,
		       TEA5777_FM_RANGELOW, TEA5777_FM_RANGEHIGH) + 8;
	do_div(freq, 16); /* to kHz */

	freq -= TEA5777_FM_IF;
	do_div(freq, TEA5777_FM_FREQ_STEP);

	tea->write_reg &= ~(TEA5777_W_FM_PLL_MASK | TEA5777_W_FM_FREF_MASK);
	tea->write_reg |= freq << TEA5777_W_FM_PLL_SHIFT;
	tea->write_reg |= TEA5777_W_FM_FREF_VALUE << TEA5777_W_FM_FREF_SHIFT;

	res = tea->ops->write_reg(tea, tea->write_reg);
	if (res)
		return res;

	tea->needs_write = false;
	tea->read_reg = -1;
	tea->freq = tea5777_freq_to_v4l2_freq(tea, freq);

	return 0;
}

static int radio_tea5777_update_read_reg(struct radio_tea5777 *tea, int wait)
{
	int res;

	if (tea->read_reg != -1)
		return 0;

	if (tea->write_before_read && tea->needs_write) {
		res = radio_tea5777_set_freq(tea);
		if (res)
			return res;
	}

	if (wait) {
		if (schedule_timeout_interruptible(msecs_to_jiffies(wait)))
			return -ERESTARTSYS;
	}

	res = tea->ops->read_reg(tea, &tea->read_reg);
	if (res)
		return res;

	tea->needs_write = true;
	return 0;
}

/*
 * Linux Video interface
 */

static int vidioc_querycap(struct file *file, void  *priv,
					struct v4l2_capability *v)
{
	struct radio_tea5777 *tea = video_drvdata(file);

	strlcpy(v->driver, tea->v4l2_dev->name, sizeof(v->driver));
	strlcpy(v->card, tea->card, sizeof(v->card));
	strlcat(v->card, " TEA5777", sizeof(v->card));
	strlcpy(v->bus_info, tea->bus_info, sizeof(v->bus_info));
	v->device_caps = V4L2_CAP_TUNER | V4L2_CAP_RADIO;
	v->device_caps |= V4L2_CAP_HW_FREQ_SEEK;
	v->capabilities = v->device_caps | V4L2_CAP_DEVICE_CAPS;
	return 0;
}

static int vidioc_g_tuner(struct file *file, void *priv,
					struct v4l2_tuner *v)
{
	struct radio_tea5777 *tea = video_drvdata(file);
	int res;

	if (v->index > 0)
		return -EINVAL;

	res = radio_tea5777_update_read_reg(tea, 0);
	if (res)
		return res;

	memset(v, 0, sizeof(*v));
	if (tea->has_am)
		strlcpy(v->name, "AM/FM", sizeof(v->name));
	else
		strlcpy(v->name, "FM", sizeof(v->name));
	v->type = V4L2_TUNER_RADIO;
	v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO |
			V4L2_TUNER_CAP_HWSEEK_BOUNDED;
	v->rangelow   = TEA5777_FM_RANGELOW;
	v->rangehigh  = TEA5777_FM_RANGEHIGH;
	v->rxsubchans = (tea->read_reg & TEA5777_R_FM_STEREO_MASK) ?
			V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO;
	v->audmode = (tea->write_reg & TEA5777_W_FM_FORCEMONO_MASK) ?
		V4L2_TUNER_MODE_MONO : V4L2_TUNER_MODE_STEREO;
	/* shift - 12 to convert 4-bits (0-15) scale to 16-bits (0-65535) */
	v->signal = (tea->read_reg & TEA5777_R_LEVEL_MASK) >>
		    (TEA5777_R_LEVEL_SHIFT - 12);

	/* Invalidate read_reg, so that next call we return up2date signal */
	tea->read_reg = -1;

	return 0;
}

static int vidioc_s_tuner(struct file *file, void *priv,
					struct v4l2_tuner *v)
{
	struct radio_tea5777 *tea = video_drvdata(file);

	if (v->index)
		return -EINVAL;

	if (v->audmode == V4L2_TUNER_MODE_MONO)
		tea->write_reg |= TEA5777_W_FM_FORCEMONO_MASK;
	else
		tea->write_reg &= ~TEA5777_W_FM_FORCEMONO_MASK;

	return radio_tea5777_set_freq(tea);
}

static int vidioc_g_frequency(struct file *file, void *priv,
					struct v4l2_frequency *f)
{
	struct radio_tea5777 *tea = video_drvdata(file);

	if (f->tuner != 0)
		return -EINVAL;
	f->type = V4L2_TUNER_RADIO;
	f->frequency = tea->freq;
	return 0;
}

static int vidioc_s_frequency(struct file *file, void *priv,
					struct v4l2_frequency *f)
{
	struct radio_tea5777 *tea = video_drvdata(file);

	if (f->tuner != 0 || f->type != V4L2_TUNER_RADIO)
		return -EINVAL;

	tea->freq = f->frequency;
	return radio_tea5777_set_freq(tea);
}

static int vidioc_s_hw_freq_seek(struct file *file, void *fh,
					struct v4l2_hw_freq_seek *a)
{
	struct radio_tea5777 *tea = video_drvdata(file);
	u32 orig_freq = tea->freq;
	unsigned long timeout;
	int res, spacing = 200 * 16; /* 200 kHz */
	/* These are fixed *for now* */
	const u32 seek_rangelow  = TEA5777_FM_RANGELOW;
	const u32 seek_rangehigh = TEA5777_FM_RANGEHIGH;

	if (a->tuner || a->wrap_around)
		return -EINVAL;

	tea->write_reg |= TEA5777_W_PROGBLIM_MASK;
	if (seek_rangelow != tea->seek_rangelow) {
		tea->write_reg &= ~TEA5777_W_UPDWN_MASK;
		tea->freq = seek_rangelow;
		res = radio_tea5777_set_freq(tea);
		if (res)
			goto leave;
		tea->seek_rangelow = tea->freq;
	}
	if (seek_rangehigh != tea->seek_rangehigh) {
		tea->write_reg |= TEA5777_W_UPDWN_MASK;
		tea->freq = seek_rangehigh;
		res = radio_tea5777_set_freq(tea);
		if (res)
			goto leave;
		tea->seek_rangehigh = tea->freq;
	}
	tea->write_reg &= ~TEA5777_W_PROGBLIM_MASK;

	tea->write_reg |= TEA5777_W_SEARCH_MASK;
	if (a->seek_upward) {
		tea->write_reg |= TEA5777_W_UPDWN_MASK;
		tea->freq = orig_freq + spacing;
	} else {
		tea->write_reg &= ~TEA5777_W_UPDWN_MASK;
		tea->freq = orig_freq - spacing;
	}
	res = radio_tea5777_set_freq(tea);
	if (res)
		goto leave;

	timeout = jiffies + msecs_to_jiffies(5000);
	for (;;) {
		if (time_after(jiffies, timeout)) {
			res = -ENODATA;
			break;
		}

		res = radio_tea5777_update_read_reg(tea, 100);
		if (res)
			break;

		/*
		 * Note we use tea->freq to track how far we've searched sofar
		 * this is necessary to ensure we continue seeking at the right
		 * point, in the write_before_read case.
		 */
		tea->freq = (tea->read_reg & TEA5777_R_FM_PLL_MASK);
		tea->freq = tea5777_freq_to_v4l2_freq(tea, tea->freq);

		if ((tea->read_reg & TEA5777_R_SFOUND_MASK)) {
			tea->write_reg &= ~TEA5777_W_SEARCH_MASK;
			return 0;
		}

		if (tea->read_reg & TEA5777_R_BLIM_MASK) {
			res = -ENODATA;
			break;
		}

		/* Force read_reg update */
		tea->read_reg = -1;
	}
leave:
	tea->write_reg &= ~TEA5777_W_PROGBLIM_MASK;
	tea->write_reg &= ~TEA5777_W_SEARCH_MASK;
	tea->freq = orig_freq;
	radio_tea5777_set_freq(tea);
	return res;
}

static int tea575x_s_ctrl(struct v4l2_ctrl *c)
{
	struct radio_tea5777 *tea =
		container_of(c->handler, struct radio_tea5777, ctrl_handler);

	switch (c->id) {
	case V4L2_CID_AUDIO_MUTE:
		if (c->val)
			tea->write_reg |= TEA5777_W_MUTE_MASK;
		else
			tea->write_reg &= ~TEA5777_W_MUTE_MASK;

		return radio_tea5777_set_freq(tea);
	}

	return -EINVAL;
}

static const struct v4l2_file_operations tea575x_fops = {
	.unlocked_ioctl	= video_ioctl2,
	.open		= v4l2_fh_open,
	.release	= v4l2_fh_release,
	.poll		= v4l2_ctrl_poll,
};

static const struct v4l2_ioctl_ops tea575x_ioctl_ops = {
	.vidioc_querycap    = vidioc_querycap,
	.vidioc_g_tuner     = vidioc_g_tuner,
	.vidioc_s_tuner     = vidioc_s_tuner,
	.vidioc_g_frequency = vidioc_g_frequency,
	.vidioc_s_frequency = vidioc_s_frequency,
	.vidioc_s_hw_freq_seek = vidioc_s_hw_freq_seek,
	.vidioc_log_status  = v4l2_ctrl_log_status,
	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
};

static const struct video_device tea575x_radio = {
	.ioctl_ops	= &tea575x_ioctl_ops,
	.release	= video_device_release_empty,
};

static const struct v4l2_ctrl_ops tea575x_ctrl_ops = {
	.s_ctrl = tea575x_s_ctrl,
};

int radio_tea5777_init(struct radio_tea5777 *tea, struct module *owner)
{
	int res;

	tea->write_reg = (1LL << TEA5777_W_IFCE_SHIFT) |
			 (1LL << TEA5777_W_IFW_SHIFT) |
			 (1LL << TEA5777_W_INTEXT_SHIFT) |
			 (1LL << TEA5777_W_CHP0_SHIFT) |
			 (2LL << TEA5777_W_SLEV_SHIFT);
	tea->freq = 90500 * 16;	/* 90.5Mhz default */
	res = radio_tea5777_set_freq(tea);
	if (res) {
		v4l2_err(tea->v4l2_dev, "can't set initial freq (%d)\n", res);
		return res;
	}

	tea->vd = tea575x_radio;
	video_set_drvdata(&tea->vd, tea);
	mutex_init(&tea->mutex);
	strlcpy(tea->vd.name, tea->v4l2_dev->name, sizeof(tea->vd.name));
	tea->vd.lock = &tea->mutex;
	tea->vd.v4l2_dev = tea->v4l2_dev;
	tea->fops = tea575x_fops;
	tea->fops.owner = owner;
	tea->vd.fops = &tea->fops;
	set_bit(V4L2_FL_USE_FH_PRIO, &tea->vd.flags);

	tea->vd.ctrl_handler = &tea->ctrl_handler;
	v4l2_ctrl_handler_init(&tea->ctrl_handler, 1);
	v4l2_ctrl_new_std(&tea->ctrl_handler, &tea575x_ctrl_ops,
			  V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
	res = tea->ctrl_handler.error;
	if (res) {
		v4l2_err(tea->v4l2_dev, "can't initialize controls\n");
		v4l2_ctrl_handler_free(&tea->ctrl_handler);
		return res;
	}
	v4l2_ctrl_handler_setup(&tea->ctrl_handler);

	res = video_register_device(&tea->vd, VFL_TYPE_RADIO, -1);
	if (res) {
		v4l2_err(tea->v4l2_dev, "can't register video device!\n");
		v4l2_ctrl_handler_free(tea->vd.ctrl_handler);
		return res;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(radio_tea5777_init);

void radio_tea5777_exit(struct radio_tea5777 *tea)
{
	video_unregister_device(&tea->vd);
	v4l2_ctrl_handler_free(tea->vd.ctrl_handler);
}
EXPORT_SYMBOL_GPL(radio_tea5777_exit);