diff options
Diffstat (limited to 'drivers/media/dvb-frontends/tda8261.c')
| -rw-r--r-- | drivers/media/dvb-frontends/tda8261.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/drivers/media/dvb-frontends/tda8261.c b/drivers/media/dvb-frontends/tda8261.c new file mode 100644 index 000000000..8b06f9274 --- /dev/null +++ b/drivers/media/dvb-frontends/tda8261.c @@ -0,0 +1,195 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + TDA8261 8PSK/QPSK tuner driver + Copyright (C) Manu Abraham (abraham.manu@gmail.com) + +*/ + + +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> + +#include <media/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_hz = 950 * MHz, + .frequency_max_hz = 2150 * MHz, + }, + + .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_hz = div_tab[config->step_size] * kHz; + + pr_info("%s: Attaching TDA8261 8PSK/QPSK tuner\n", __func__); + + return fe; + +exit: + kfree(state); + return NULL; +} + +EXPORT_SYMBOL_GPL(tda8261_attach); + +MODULE_AUTHOR("Manu Abraham"); +MODULE_DESCRIPTION("TDA8261 8PSK/QPSK Tuner"); +MODULE_LICENSE("GPL"); |