linux/drivers/media/dvb-frontends/tda8261.c

209 lines
5.2 KiB
C

/*
TDA8261 8PSK/QPSK tuner driver
Copyright (C) Manu Abraham (abraham.manu@gmail.com)
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/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include "dvb_frontend.h"
#include "tda8261.h"
struct tda8261_state {
struct dvb_frontend *fe;
struct i2c_adapter *i2c;
const struct tda8261_config *config;
/* state cache */
u32 frequency;
u32 bandwidth;
};
static int tda8261_read(struct tda8261_state *state, u8 *buf)
{
const struct tda8261_config *config = state->config;
int err = 0;
struct i2c_msg msg = { .addr = config->addr, .flags = I2C_M_RD,.buf = buf, .len = 1 };
if ((err = i2c_transfer(state->i2c, &msg, 1)) != 1)
pr_err("%s: read error, err=%d\n", __func__, err);
return err;
}
static int tda8261_write(struct tda8261_state *state, u8 *buf)
{
const struct tda8261_config *config = state->config;
int err = 0;
struct i2c_msg msg = { .addr = config->addr, .flags = 0, .buf = buf, .len = 4 };
if ((err = i2c_transfer(state->i2c, &msg, 1)) != 1)
pr_err("%s: write error, err=%d\n", __func__, err);
return err;
}
static int tda8261_get_status(struct dvb_frontend *fe, u32 *status)
{
struct tda8261_state *state = fe->tuner_priv;
u8 result = 0;
int err = 0;
*status = 0;
if ((err = tda8261_read(state, &result)) < 0) {
pr_err("%s: I/O Error\n", __func__);
return err;
}
if ((result >> 6) & 0x01) {
pr_debug("%s: Tuner Phase Locked\n", __func__);
*status = 1;
}
return err;
}
static const u32 div_tab[] = { 2000, 1000, 500, 250, 125 }; /* kHz */
static const u8 ref_div[] = { 0x00, 0x01, 0x02, 0x05, 0x07 };
static int tda8261_get_frequency(struct dvb_frontend *fe, u32 *frequency)
{
struct tda8261_state *state = fe->tuner_priv;
*frequency = state->frequency;
return 0;
}
static int tda8261_set_params(struct dvb_frontend *fe)
{
struct dtv_frontend_properties *c = &fe->dtv_property_cache;
struct tda8261_state *state = fe->tuner_priv;
const struct tda8261_config *config = state->config;
u32 frequency, N, status = 0;
u8 buf[4];
int err = 0;
/*
* N = Max VCO Frequency / Channel Spacing
* Max VCO Frequency = VCO frequency + (channel spacing - 1)
* (to account for half channel spacing on either side)
*/
frequency = c->frequency;
if ((frequency < 950000) || (frequency > 2150000)) {
pr_warn("%s: Frequency beyond limits, frequency=%d\n",
__func__, frequency);
return -EINVAL;
}
N = (frequency + (div_tab[config->step_size] - 1)) / div_tab[config->step_size];
pr_debug("%s: Step size=%d, Divider=%d, PG=0x%02x (%d)\n",
__func__, config->step_size, div_tab[config->step_size], N, N);
buf[0] = (N >> 8) & 0xff;
buf[1] = N & 0xff;
buf[2] = (0x01 << 7) | ((ref_div[config->step_size] & 0x07) << 1);
if (frequency < 1450000)
buf[3] = 0x00;
else if (frequency < 2000000)
buf[3] = 0x40;
else if (frequency < 2150000)
buf[3] = 0x80;
/* Set params */
err = tda8261_write(state, buf);
if (err < 0) {
pr_err("%s: I/O Error\n", __func__);
return err;
}
/* sleep for some time */
pr_debug("%s: Waiting to Phase LOCK\n", __func__);
msleep(20);
/* check status */
if ((err = tda8261_get_status(fe, &status)) < 0) {
pr_err("%s: I/O Error\n", __func__);
return err;
}
if (status == 1) {
pr_debug("%s: Tuner Phase locked: status=%d\n", __func__,
status);
state->frequency = frequency; /* cache successful state */
} else {
pr_debug("%s: No Phase lock: status=%d\n", __func__, status);
}
return 0;
}
static void tda8261_release(struct dvb_frontend *fe)
{
struct tda8261_state *state = fe->tuner_priv;
fe->tuner_priv = NULL;
kfree(state);
}
static const struct dvb_tuner_ops tda8261_ops = {
.info = {
.name = "TDA8261",
.frequency_min = 950000,
.frequency_max = 2150000,
.frequency_step = 0
},
.set_params = tda8261_set_params,
.get_frequency = tda8261_get_frequency,
.get_status = tda8261_get_status,
.release = tda8261_release
};
struct dvb_frontend *tda8261_attach(struct dvb_frontend *fe,
const struct tda8261_config *config,
struct i2c_adapter *i2c)
{
struct tda8261_state *state = NULL;
if ((state = kzalloc(sizeof (struct tda8261_state), GFP_KERNEL)) == NULL)
goto exit;
state->config = config;
state->i2c = i2c;
state->fe = fe;
fe->tuner_priv = state;
fe->ops.tuner_ops = tda8261_ops;
fe->ops.tuner_ops.info.frequency_step = div_tab[config->step_size];
pr_info("%s: Attaching TDA8261 8PSK/QPSK tuner\n", __func__);
return fe;
exit:
kfree(state);
return NULL;
}
EXPORT_SYMBOL(tda8261_attach);
MODULE_AUTHOR("Manu Abraham");
MODULE_DESCRIPTION("TDA8261 8PSK/QPSK Tuner");
MODULE_LICENSE("GPL");