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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hdpvr-i2c.c (4996B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2
      3/*
      4 * Hauppauge HD PVR USB driver
      5 *
      6 * Copyright (C) 2008      Janne Grunau (j@jannau.net)
      7 *
      8 * IR device registration code is
      9 * Copyright (C) 2010	Andy Walls <awalls@md.metrocast.net>
     10 */
     11
     12#if IS_ENABLED(CONFIG_I2C)
     13
     14#include <linux/i2c.h>
     15#include <linux/slab.h>
     16#include <linux/export.h>
     17
     18#include "hdpvr.h"
     19
     20#define CTRL_READ_REQUEST	0xb8
     21#define CTRL_WRITE_REQUEST	0x38
     22
     23#define REQTYPE_I2C_READ	0xb1
     24#define REQTYPE_I2C_WRITE	0xb0
     25#define REQTYPE_I2C_WRITE_STATT	0xd0
     26
     27#define Z8F0811_IR_TX_I2C_ADDR	0x70
     28#define Z8F0811_IR_RX_I2C_ADDR	0x71
     29
     30
     31struct i2c_client *hdpvr_register_ir_i2c(struct hdpvr_device *dev)
     32{
     33	struct IR_i2c_init_data *init_data = &dev->ir_i2c_init_data;
     34	struct i2c_board_info info = {
     35		I2C_BOARD_INFO("ir_z8f0811_hdpvr", Z8F0811_IR_RX_I2C_ADDR),
     36	};
     37
     38	/* Our default information for ir-kbd-i2c.c to use */
     39	init_data->ir_codes = RC_MAP_HAUPPAUGE;
     40	init_data->internal_get_key_func = IR_KBD_GET_KEY_HAUP_XVR;
     41	init_data->type = RC_PROTO_BIT_RC5 | RC_PROTO_BIT_RC6_MCE |
     42			  RC_PROTO_BIT_RC6_6A_32;
     43	init_data->name = "HD-PVR";
     44	init_data->polling_interval = 405; /* ms, duplicated from Windows */
     45	info.platform_data = init_data;
     46
     47	return i2c_new_client_device(&dev->i2c_adapter, &info);
     48}
     49
     50static int hdpvr_i2c_read(struct hdpvr_device *dev, int bus,
     51			  unsigned char addr, char *wdata, int wlen,
     52			  char *data, int len)
     53{
     54	int ret;
     55
     56	if ((len > sizeof(dev->i2c_buf)) || (wlen > sizeof(dev->i2c_buf)))
     57		return -EINVAL;
     58
     59	if (wlen) {
     60		memcpy(dev->i2c_buf, wdata, wlen);
     61		ret = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
     62				      REQTYPE_I2C_WRITE, CTRL_WRITE_REQUEST,
     63				      (bus << 8) | addr, 0, dev->i2c_buf,
     64				      wlen, 1000);
     65		if (ret < 0)
     66			return ret;
     67	}
     68
     69	ret = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
     70			      REQTYPE_I2C_READ, CTRL_READ_REQUEST,
     71			      (bus << 8) | addr, 0, dev->i2c_buf, len, 1000);
     72
     73	if (ret == len) {
     74		memcpy(data, dev->i2c_buf, len);
     75		ret = 0;
     76	} else if (ret >= 0)
     77		ret = -EIO;
     78
     79	return ret;
     80}
     81
     82static int hdpvr_i2c_write(struct hdpvr_device *dev, int bus,
     83			   unsigned char addr, char *data, int len)
     84{
     85	int ret;
     86
     87	if (len > sizeof(dev->i2c_buf))
     88		return -EINVAL;
     89
     90	memcpy(dev->i2c_buf, data, len);
     91	ret = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
     92			      REQTYPE_I2C_WRITE, CTRL_WRITE_REQUEST,
     93			      (bus << 8) | addr, 0, dev->i2c_buf, len, 1000);
     94
     95	if (ret < 0)
     96		return ret;
     97
     98	ret = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
     99			      REQTYPE_I2C_WRITE_STATT, CTRL_READ_REQUEST,
    100			      0, 0, dev->i2c_buf, 2, 1000);
    101
    102	if ((ret == 2) && (dev->i2c_buf[1] == (len - 1)))
    103		ret = 0;
    104	else if (ret >= 0)
    105		ret = -EIO;
    106
    107	return ret;
    108}
    109
    110static int hdpvr_transfer(struct i2c_adapter *i2c_adapter, struct i2c_msg *msgs,
    111			  int num)
    112{
    113	struct hdpvr_device *dev = i2c_get_adapdata(i2c_adapter);
    114	int retval = 0, addr;
    115
    116	mutex_lock(&dev->i2c_mutex);
    117
    118	addr = msgs[0].addr << 1;
    119
    120	if (num == 1) {
    121		if (msgs[0].flags & I2C_M_RD)
    122			retval = hdpvr_i2c_read(dev, 1, addr, NULL, 0,
    123						msgs[0].buf, msgs[0].len);
    124		else
    125			retval = hdpvr_i2c_write(dev, 1, addr, msgs[0].buf,
    126						 msgs[0].len);
    127	} else if (num == 2) {
    128		if (msgs[0].addr != msgs[1].addr) {
    129			v4l2_warn(&dev->v4l2_dev, "refusing 2-phase i2c xfer with conflicting target addresses\n");
    130			retval = -EINVAL;
    131			goto out;
    132		}
    133
    134		if ((msgs[0].flags & I2C_M_RD) || !(msgs[1].flags & I2C_M_RD)) {
    135			v4l2_warn(&dev->v4l2_dev, "refusing complex xfer with r0=%d, r1=%d\n",
    136				  msgs[0].flags & I2C_M_RD,
    137				  msgs[1].flags & I2C_M_RD);
    138			retval = -EINVAL;
    139			goto out;
    140		}
    141
    142		/*
    143		 * Write followed by atomic read is the only complex xfer that
    144		 * we actually support here.
    145		 */
    146		retval = hdpvr_i2c_read(dev, 1, addr, msgs[0].buf, msgs[0].len,
    147					msgs[1].buf, msgs[1].len);
    148	} else {
    149		v4l2_warn(&dev->v4l2_dev, "refusing %d-phase i2c xfer\n", num);
    150	}
    151
    152out:
    153	mutex_unlock(&dev->i2c_mutex);
    154
    155	return retval ? retval : num;
    156}
    157
    158static u32 hdpvr_functionality(struct i2c_adapter *adapter)
    159{
    160	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
    161}
    162
    163static const struct i2c_algorithm hdpvr_algo = {
    164	.master_xfer   = hdpvr_transfer,
    165	.functionality = hdpvr_functionality,
    166};
    167
    168static const struct i2c_adapter hdpvr_i2c_adapter_template = {
    169	.name   = "Hauppauge HD PVR I2C",
    170	.owner  = THIS_MODULE,
    171	.algo   = &hdpvr_algo,
    172};
    173
    174static int hdpvr_activate_ir(struct hdpvr_device *dev)
    175{
    176	char buffer[2];
    177
    178	mutex_lock(&dev->i2c_mutex);
    179
    180	hdpvr_i2c_read(dev, 0, 0x54, NULL, 0, buffer, 1);
    181
    182	buffer[0] = 0;
    183	buffer[1] = 0x8;
    184	hdpvr_i2c_write(dev, 1, 0x54, buffer, 2);
    185
    186	buffer[1] = 0x18;
    187	hdpvr_i2c_write(dev, 1, 0x54, buffer, 2);
    188
    189	mutex_unlock(&dev->i2c_mutex);
    190
    191	return 0;
    192}
    193
    194int hdpvr_register_i2c_adapter(struct hdpvr_device *dev)
    195{
    196	hdpvr_activate_ir(dev);
    197
    198	dev->i2c_adapter = hdpvr_i2c_adapter_template;
    199	dev->i2c_adapter.dev.parent = &dev->udev->dev;
    200
    201	i2c_set_adapdata(&dev->i2c_adapter, dev);
    202
    203	return i2c_add_adapter(&dev->i2c_adapter);
    204}
    205
    206#endif