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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3	TDA8261 8PSK/QPSK tuner driver4	Copyright (C) Manu Abraham (abraham.manu@gmail.com)5 6*/7 8 9#include <linux/init.h>10#include <linux/kernel.h>11#include <linux/module.h>12#include <linux/slab.h>13 14#include <media/dvb_frontend.h>15#include "tda8261.h"16 17struct tda8261_state {18	struct dvb_frontend		*fe;19	struct i2c_adapter		*i2c;20	const struct tda8261_config	*config;21 22	/* state cache */23	u32 frequency;24	u32 bandwidth;25};26 27static int tda8261_read(struct tda8261_state *state, u8 *buf)28{29	const struct tda8261_config *config = state->config;30	int err = 0;31	struct i2c_msg msg = { .addr	= config->addr, .flags = I2C_M_RD,.buf = buf,  .len = 1 };32 33	if ((err = i2c_transfer(state->i2c, &msg, 1)) != 1)34		pr_err("%s: read error, err=%d\n", __func__, err);35 36	return err;37}38 39static int tda8261_write(struct tda8261_state *state, u8 *buf)40{41	const struct tda8261_config *config = state->config;42	int err = 0;43	struct i2c_msg msg = { .addr = config->addr, .flags = 0, .buf = buf, .len = 4 };44 45	if ((err = i2c_transfer(state->i2c, &msg, 1)) != 1)46		pr_err("%s: write error, err=%d\n", __func__, err);47 48	return err;49}50 51static int tda8261_get_status(struct dvb_frontend *fe, u32 *status)52{53	struct tda8261_state *state = fe->tuner_priv;54	u8 result = 0;55	int err = 0;56 57	*status = 0;58 59	if ((err = tda8261_read(state, &result)) < 0) {60		pr_err("%s: I/O Error\n", __func__);61		return err;62	}63	if ((result >> 6) & 0x01) {64		pr_debug("%s: Tuner Phase Locked\n", __func__);65		*status = 1;66	}67 68	return err;69}70 71static const u32 div_tab[] = { 2000, 1000,  500,  250,  125 }; /* kHz */72static const u8  ref_div[] = { 0x00, 0x01, 0x02, 0x05, 0x07 };73 74static int tda8261_get_frequency(struct dvb_frontend *fe, u32 *frequency)75{76	struct tda8261_state *state = fe->tuner_priv;77 78	*frequency = state->frequency;79 80	return 0;81}82 83static int tda8261_set_params(struct dvb_frontend *fe)84{85	struct dtv_frontend_properties *c = &fe->dtv_property_cache;86	struct tda8261_state *state = fe->tuner_priv;87	const struct tda8261_config *config = state->config;88	u32 frequency, N, status = 0;89	u8 buf[4];90	int err = 0;91 92	/*93	 * N = Max VCO Frequency / Channel Spacing94	 * Max VCO Frequency = VCO frequency + (channel spacing - 1)95	 * (to account for half channel spacing on either side)96	 */97	frequency = c->frequency;98	if ((frequency < 950000) || (frequency > 2150000)) {99		pr_warn("%s: Frequency beyond limits, frequency=%d\n",100			__func__, frequency);101		return -EINVAL;102	}103	N = (frequency + (div_tab[config->step_size] - 1)) / div_tab[config->step_size];104	pr_debug("%s: Step size=%d, Divider=%d, PG=0x%02x (%d)\n",105		__func__, config->step_size, div_tab[config->step_size], N, N);106 107	buf[0] = (N >> 8) & 0xff;108	buf[1] = N & 0xff;109	buf[2] = (0x01 << 7) | ((ref_div[config->step_size] & 0x07) << 1);110 111	if (frequency < 1450000)112		buf[3] = 0x00;113	else if (frequency < 2000000)114		buf[3] = 0x40;115	else if (frequency < 2150000)116		buf[3] = 0x80;117 118	/* Set params */119	err = tda8261_write(state, buf);120	if (err < 0) {121		pr_err("%s: I/O Error\n", __func__);122		return err;123	}124	/* sleep for some time */125	pr_debug("%s: Waiting to Phase LOCK\n", __func__);126	msleep(20);127	/* check status */128	if ((err = tda8261_get_status(fe, &status)) < 0) {129		pr_err("%s: I/O Error\n", __func__);130		return err;131	}132	if (status == 1) {133		pr_debug("%s: Tuner Phase locked: status=%d\n", __func__,134			 status);135		state->frequency = frequency; /* cache successful state */136	} else {137		pr_debug("%s: No Phase lock: status=%d\n", __func__, status);138	}139 140	return 0;141}142 143static void tda8261_release(struct dvb_frontend *fe)144{145	struct tda8261_state *state = fe->tuner_priv;146 147	fe->tuner_priv = NULL;148	kfree(state);149}150 151static const struct dvb_tuner_ops tda8261_ops = {152 153	.info = {154		.name		   = "TDA8261",155		.frequency_min_hz  =  950 * MHz,156		.frequency_max_hz  = 2150 * MHz,157	},158 159	.set_params	= tda8261_set_params,160	.get_frequency	= tda8261_get_frequency,161	.get_status	= tda8261_get_status,162	.release	= tda8261_release163};164 165struct dvb_frontend *tda8261_attach(struct dvb_frontend *fe,166				    const struct tda8261_config *config,167				    struct i2c_adapter *i2c)168{169	struct tda8261_state *state = NULL;170 171	if ((state = kzalloc(sizeof (struct tda8261_state), GFP_KERNEL)) == NULL)172		goto exit;173 174	state->config		= config;175	state->i2c		= i2c;176	state->fe		= fe;177	fe->tuner_priv		= state;178	fe->ops.tuner_ops	= tda8261_ops;179 180	fe->ops.tuner_ops.info.frequency_step_hz = div_tab[config->step_size] * kHz;181 182	pr_info("%s: Attaching TDA8261 8PSK/QPSK tuner\n", __func__);183 184	return fe;185 186exit:187	kfree(state);188	return NULL;189}190 191EXPORT_SYMBOL_GPL(tda8261_attach);192 193MODULE_AUTHOR("Manu Abraham");194MODULE_DESCRIPTION("TDA8261 8PSK/QPSK Tuner");195MODULE_LICENSE("GPL");196