cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

m52790.c (4626B)


      1// SPDX-License-Identifier: GPL-2.0-or-later
      2/*
      3 * m52790 i2c ivtv driver.
      4 * Copyright (C) 2007  Hans Verkuil
      5 *
      6 * A/V source switching Mitsubishi M52790SP/FP
      7 */
      8
      9
     10#include <linux/module.h>
     11#include <linux/types.h>
     12#include <linux/slab.h>
     13#include <linux/ioctl.h>
     14#include <linux/uaccess.h>
     15#include <linux/i2c.h>
     16#include <linux/videodev2.h>
     17#include <media/i2c/m52790.h>
     18#include <media/v4l2-device.h>
     19
     20MODULE_DESCRIPTION("i2c device driver for m52790 A/V switch");
     21MODULE_AUTHOR("Hans Verkuil");
     22MODULE_LICENSE("GPL");
     23
     24
     25struct m52790_state {
     26	struct v4l2_subdev sd;
     27	u16 input;
     28	u16 output;
     29};
     30
     31static inline struct m52790_state *to_state(struct v4l2_subdev *sd)
     32{
     33	return container_of(sd, struct m52790_state, sd);
     34}
     35
     36/* ----------------------------------------------------------------------- */
     37
     38static int m52790_write(struct v4l2_subdev *sd)
     39{
     40	struct m52790_state *state = to_state(sd);
     41	struct i2c_client *client = v4l2_get_subdevdata(sd);
     42
     43	u8 sw1 = (state->input | state->output) & 0xff;
     44	u8 sw2 = (state->input | state->output) >> 8;
     45
     46	return i2c_smbus_write_byte_data(client, sw1, sw2);
     47}
     48
     49/* Note: audio and video are linked and cannot be switched separately.
     50   So audio and video routing commands are identical for this chip.
     51   In theory the video amplifier and audio modes could be handled
     52   separately for the output, but that seems to be overkill right now.
     53   The same holds for implementing an audio mute control, this is now
     54   part of the audio output routing. The normal case is that another
     55   chip takes care of the actual muting so making it part of the
     56   output routing seems to be the right thing to do for now. */
     57static int m52790_s_routing(struct v4l2_subdev *sd,
     58			    u32 input, u32 output, u32 config)
     59{
     60	struct m52790_state *state = to_state(sd);
     61
     62	state->input = input;
     63	state->output = output;
     64	m52790_write(sd);
     65	return 0;
     66}
     67
     68#ifdef CONFIG_VIDEO_ADV_DEBUG
     69static int m52790_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
     70{
     71	struct m52790_state *state = to_state(sd);
     72
     73	if (reg->reg != 0)
     74		return -EINVAL;
     75	reg->size = 1;
     76	reg->val = state->input | state->output;
     77	return 0;
     78}
     79
     80static int m52790_s_register(struct v4l2_subdev *sd, const struct v4l2_dbg_register *reg)
     81{
     82	struct m52790_state *state = to_state(sd);
     83
     84	if (reg->reg != 0)
     85		return -EINVAL;
     86	state->input = reg->val & 0x0303;
     87	state->output = reg->val & ~0x0303;
     88	m52790_write(sd);
     89	return 0;
     90}
     91#endif
     92
     93static int m52790_log_status(struct v4l2_subdev *sd)
     94{
     95	struct m52790_state *state = to_state(sd);
     96
     97	v4l2_info(sd, "Switch 1: %02x\n",
     98			(state->input | state->output) & 0xff);
     99	v4l2_info(sd, "Switch 2: %02x\n",
    100			(state->input | state->output) >> 8);
    101	return 0;
    102}
    103
    104/* ----------------------------------------------------------------------- */
    105
    106static const struct v4l2_subdev_core_ops m52790_core_ops = {
    107	.log_status = m52790_log_status,
    108#ifdef CONFIG_VIDEO_ADV_DEBUG
    109	.g_register = m52790_g_register,
    110	.s_register = m52790_s_register,
    111#endif
    112};
    113
    114static const struct v4l2_subdev_audio_ops m52790_audio_ops = {
    115	.s_routing = m52790_s_routing,
    116};
    117
    118static const struct v4l2_subdev_video_ops m52790_video_ops = {
    119	.s_routing = m52790_s_routing,
    120};
    121
    122static const struct v4l2_subdev_ops m52790_ops = {
    123	.core = &m52790_core_ops,
    124	.audio = &m52790_audio_ops,
    125	.video = &m52790_video_ops,
    126};
    127
    128/* ----------------------------------------------------------------------- */
    129
    130/* i2c implementation */
    131
    132static int m52790_probe(struct i2c_client *client,
    133			const struct i2c_device_id *id)
    134{
    135	struct m52790_state *state;
    136	struct v4l2_subdev *sd;
    137
    138	/* Check if the adapter supports the needed features */
    139	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
    140		return -EIO;
    141
    142	v4l_info(client, "chip found @ 0x%x (%s)\n",
    143			client->addr << 1, client->adapter->name);
    144
    145	state = devm_kzalloc(&client->dev, sizeof(*state), GFP_KERNEL);
    146	if (state == NULL)
    147		return -ENOMEM;
    148
    149	sd = &state->sd;
    150	v4l2_i2c_subdev_init(sd, client, &m52790_ops);
    151	state->input = M52790_IN_TUNER;
    152	state->output = M52790_OUT_STEREO;
    153	m52790_write(sd);
    154	return 0;
    155}
    156
    157static int m52790_remove(struct i2c_client *client)
    158{
    159	struct v4l2_subdev *sd = i2c_get_clientdata(client);
    160
    161	v4l2_device_unregister_subdev(sd);
    162	return 0;
    163}
    164
    165/* ----------------------------------------------------------------------- */
    166
    167static const struct i2c_device_id m52790_id[] = {
    168	{ "m52790", 0 },
    169	{ }
    170};
    171MODULE_DEVICE_TABLE(i2c, m52790_id);
    172
    173static struct i2c_driver m52790_driver = {
    174	.driver = {
    175		.name	= "m52790",
    176	},
    177	.probe		= m52790_probe,
    178	.remove		= m52790_remove,
    179	.id_table	= m52790_id,
    180};
    181
    182module_i2c_driver(m52790_driver);