cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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tda8261.c (4699B)


      1// SPDX-License-Identifier: GPL-2.0-or-later
      2/*
      3	TDA8261 8PSK/QPSK tuner driver
      4	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 Spacing
     94	 * 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_release
    163};
    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(tda8261_attach);
    192
    193MODULE_AUTHOR("Manu Abraham");
    194MODULE_DESCRIPTION("TDA8261 8PSK/QPSK Tuner");
    195MODULE_LICENSE("GPL");