1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *  Driver for Dummy Frontend
4 *
5 *  Written by Emard <emard@softhome.net>
6 */
7
8#include <linux/module.h>
9#include <linux/init.h>
10#include <linux/string.h>
11#include <linux/slab.h>
12
13#include <media/dvb_frontend.h>
14#include "ddbridge-dummy-fe.h"
15
16struct ddbridge_dummy_fe_state {
17	struct dvb_frontend frontend;
18};
19
20static int ddbridge_dummy_fe_read_status(struct dvb_frontend *fe,
21				    enum fe_status *status)
22{
23	*status = FE_HAS_SIGNAL
24		| FE_HAS_CARRIER
25		| FE_HAS_VITERBI
26		| FE_HAS_SYNC
27		| FE_HAS_LOCK;
28
29	return 0;
30}
31
32static int ddbridge_dummy_fe_read_ber(struct dvb_frontend *fe, u32 *ber)
33{
34	*ber = 0;
35	return 0;
36}
37
38static int ddbridge_dummy_fe_read_signal_strength(struct dvb_frontend *fe,
39					     u16 *strength)
40{
41	*strength = 0;
42	return 0;
43}
44
45static int ddbridge_dummy_fe_read_snr(struct dvb_frontend *fe, u16 *snr)
46{
47	*snr = 0;
48	return 0;
49}
50
51static int ddbridge_dummy_fe_read_ucblocks(struct dvb_frontend *fe, u32 *ucblocks)
52{
53	*ucblocks = 0;
54	return 0;
55}
56
57/*
58 * Should only be implemented if it actually reads something from the hardware.
59 * Also, it should check for the locks, in order to avoid report wrong data
60 * to userspace.
61 */
62static int ddbridge_dummy_fe_get_frontend(struct dvb_frontend *fe,
63				     struct dtv_frontend_properties *p)
64{
65	return 0;
66}
67
68static int ddbridge_dummy_fe_set_frontend(struct dvb_frontend *fe)
69{
70	if (fe->ops.tuner_ops.set_params) {
71		fe->ops.tuner_ops.set_params(fe);
72		if (fe->ops.i2c_gate_ctrl)
73			fe->ops.i2c_gate_ctrl(fe, 0);
74	}
75
76	return 0;
77}
78
79static int ddbridge_dummy_fe_sleep(struct dvb_frontend *fe)
80{
81	return 0;
82}
83
84static int ddbridge_dummy_fe_init(struct dvb_frontend *fe)
85{
86	return 0;
87}
88
89static void ddbridge_dummy_fe_release(struct dvb_frontend *fe)
90{
91	struct ddbridge_dummy_fe_state *state = fe->demodulator_priv;
92
93	kfree(state);
94}
95
96static const struct dvb_frontend_ops ddbridge_dummy_fe_qam_ops;
97
98struct dvb_frontend *ddbridge_dummy_fe_qam_attach(void)
99{
100	struct ddbridge_dummy_fe_state *state = NULL;
101
102	/* allocate memory for the internal state */
103	state = kzalloc(sizeof(struct ddbridge_dummy_fe_state), GFP_KERNEL);
104	if (!state)
105		return NULL;
106
107	/* create dvb_frontend */
108	memcpy(&state->frontend.ops,
109	       &ddbridge_dummy_fe_qam_ops,
110	       sizeof(struct dvb_frontend_ops));
111
112	state->frontend.demodulator_priv = state;
113	return &state->frontend;
114}
115EXPORT_SYMBOL_GPL(ddbridge_dummy_fe_qam_attach);
116
117static const struct dvb_frontend_ops ddbridge_dummy_fe_qam_ops = {
118	.delsys = { SYS_DVBC_ANNEX_A },
119	.info = {
120		.name			= "ddbridge dummy DVB-C",
121		.frequency_min_hz	=  51 * MHz,
122		.frequency_max_hz	= 858 * MHz,
123		.frequency_stepsize_hz	= 62500,
124		/* symbol_rate_min: SACLK/64 == (XIN/2)/64 */
125		.symbol_rate_min	= (57840000 / 2) / 64,
126		.symbol_rate_max	= (57840000 / 2) / 4,   /* SACLK/4 */
127		.caps = FE_CAN_QAM_16 |
128			FE_CAN_QAM_32 |
129			FE_CAN_QAM_64 |
130			FE_CAN_QAM_128 |
131			FE_CAN_QAM_256 |
132			FE_CAN_FEC_AUTO |
133			FE_CAN_INVERSION_AUTO
134	},
135
136	.release = ddbridge_dummy_fe_release,
137
138	.init = ddbridge_dummy_fe_init,
139	.sleep = ddbridge_dummy_fe_sleep,
140
141	.set_frontend = ddbridge_dummy_fe_set_frontend,
142	.get_frontend = ddbridge_dummy_fe_get_frontend,
143
144	.read_status = ddbridge_dummy_fe_read_status,
145	.read_ber = ddbridge_dummy_fe_read_ber,
146	.read_signal_strength = ddbridge_dummy_fe_read_signal_strength,
147	.read_snr = ddbridge_dummy_fe_read_snr,
148	.read_ucblocks = ddbridge_dummy_fe_read_ucblocks,
149};
150
151MODULE_DESCRIPTION("ddbridge dummy Frontend");
152MODULE_AUTHOR("Emard");
153MODULE_LICENSE("GPL");
154