drivers/media/pci/ddbridge/ddbridge-dummy-fe.c

   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
  16 struct ddbridge_dummy_fe_state {
  17         struct dvb_frontend frontend;
  18 };
  19
  20 static 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
  32 static int ddbridge_dummy_fe_read_ber(struct dvb_frontend *fe, u32 *ber)
  33 {
  34         *ber = 0;
  35         return 0;
  36 }
  37
  38 static int ddbridge_dummy_fe_read_signal_strength(struct dvb_frontend *fe,
  39                                              u16 *strength)
  40 {
  41         *strength = 0;
  42         return 0;
  43 }
  44
  45 static int ddbridge_dummy_fe_read_snr(struct dvb_frontend *fe, u16 *snr)
  46 {
  47         *snr = 0;
  48         return 0;
  49 }
  50
  51 static 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  */
  62 static int ddbridge_dummy_fe_get_frontend(struct dvb_frontend *fe,
  63                                      struct dtv_frontend_properties *p)
  64 {
  65         return 0;
  66 }
  67
  68 static 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
  79 static int ddbridge_dummy_fe_sleep(struct dvb_frontend *fe)
  80 {
  81         return 0;
  82 }
  83
  84 static int ddbridge_dummy_fe_init(struct dvb_frontend *fe)
  85 {
  86         return 0;
  87 }
  88
  89 static 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
  96 static const struct dvb_frontend_ops ddbridge_dummy_fe_qam_ops;
  97
  98 struct 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 }
 115 EXPORT_SYMBOL(ddbridge_dummy_fe_qam_attach);
 116
 117 static 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
 151 MODULE_DESCRIPTION("ddbridge dummy Frontend");
 152 MODULE_AUTHOR("Emard");
 153 MODULE_LICENSE("GPL");