1// SPDX-License-Identifier: GPL-2.0-or-later
2/* cx25840 firmware functions
3 */
4
5#include <linux/module.h>
6#include <linux/i2c.h>
7#include <linux/firmware.h>
8#include <media/v4l2-common.h>
9#include <media/drv-intf/cx25840.h>
10
11#include "cx25840-core.h"
12
13/*
14 * Mike Isely <isely@pobox.com> - The FWSEND parameter controls the
15 * size of the firmware chunks sent down the I2C bus to the chip.
16 * Previously this had been set to 1024 but unfortunately some I2C
17 * implementations can't transfer data in such big gulps.
18 * Specifically, the pvrusb2 driver has a hard limit of around 60
19 * bytes, due to the encapsulation there of I2C traffic into USB
20 * messages.  So we have to significantly reduce this parameter.
21 */
22#define FWSEND 48
23
24#define FWDEV(x) &((x)->dev)
25
26static char *firmware = "";
27
28module_param(firmware, charp, 0444);
29
30MODULE_PARM_DESC(firmware, "Firmware image to load");
31
32static void start_fw_load(struct i2c_client *client)
33{
34	/* DL_ADDR_LB=0 DL_ADDR_HB=0 */
35	cx25840_write(client, 0x800, 0x00);
36	cx25840_write(client, 0x801, 0x00);
37	// DL_MAP=3 DL_AUTO_INC=0 DL_ENABLE=1
38	cx25840_write(client, 0x803, 0x0b);
39	/* AUTO_INC_DIS=1 */
40	cx25840_write(client, 0x000, 0x20);
41}
42
43static void end_fw_load(struct i2c_client *client)
44{
45	/* AUTO_INC_DIS=0 */
46	cx25840_write(client, 0x000, 0x00);
47	/* DL_ENABLE=0 */
48	cx25840_write(client, 0x803, 0x03);
49}
50
51#define CX2388x_FIRMWARE "v4l-cx23885-avcore-01.fw"
52#define CX231xx_FIRMWARE "v4l-cx231xx-avcore-01.fw"
53#define CX25840_FIRMWARE "v4l-cx25840.fw"
54
55static const char *get_fw_name(struct i2c_client *client)
56{
57	struct cx25840_state *state = to_state(i2c_get_clientdata(client));
58
59	if (firmware[0])
60		return firmware;
61	if (is_cx2388x(state))
62		return CX2388x_FIRMWARE;
63	if (is_cx231xx(state))
64		return CX231xx_FIRMWARE;
65	return CX25840_FIRMWARE;
66}
67
68static int check_fw_load(struct i2c_client *client, int size)
69{
70	/* DL_ADDR_HB DL_ADDR_LB */
71	int s = cx25840_read(client, 0x801) << 8;
72	s |= cx25840_read(client, 0x800);
73
74	if (size != s) {
75		v4l_err(client, "firmware %s load failed\n",
76				get_fw_name(client));
77		return -EINVAL;
78	}
79
80	v4l_info(client, "loaded %s firmware (%d bytes)\n",
81			get_fw_name(client), size);
82	return 0;
83}
84
85static int fw_write(struct i2c_client *client, const u8 *data, int size)
86{
87	if (i2c_master_send(client, data, size) < size) {
88		v4l_err(client, "firmware load i2c failure\n");
89		return -ENOSYS;
90	}
91
92	return 0;
93}
94
95int cx25840_loadfw(struct i2c_client *client)
96{
97	struct cx25840_state *state = to_state(i2c_get_clientdata(client));
98	const struct firmware *fw = NULL;
99	u8 buffer[FWSEND];
100	const u8 *ptr;
101	const char *fwname = get_fw_name(client);
102	int size, retval;
103	int max_buf_size = FWSEND;
104	u32 gpio_oe = 0, gpio_da = 0;
105
106	if (is_cx2388x(state)) {
107		/* Preserve the GPIO OE and output bits */
108		gpio_oe = cx25840_read(client, 0x160);
109		gpio_da = cx25840_read(client, 0x164);
110	}
111
112	/* cx231xx cannot accept more than 16 bytes at a time */
113	if (is_cx231xx(state) && max_buf_size > 16)
114		max_buf_size = 16;
115
116	if (request_firmware(&fw, fwname, FWDEV(client)) != 0) {
117		v4l_err(client, "unable to open firmware %s\n", fwname);
118		return -EINVAL;
119	}
120
121	start_fw_load(client);
122
123	buffer[0] = 0x08;
124	buffer[1] = 0x02;
125
126	size = fw->size;
127	ptr = fw->data;
128	while (size > 0) {
129		int len = min(max_buf_size - 2, size);
130
131		memcpy(buffer + 2, ptr, len);
132
133		retval = fw_write(client, buffer, len + 2);
134
135		if (retval < 0) {
136			release_firmware(fw);
137			return retval;
138		}
139
140		size -= len;
141		ptr += len;
142	}
143
144	end_fw_load(client);
145
146	size = fw->size;
147	release_firmware(fw);
148
149	if (is_cx2388x(state)) {
150		/* Restore GPIO configuration after f/w load */
151		cx25840_write(client, 0x160, gpio_oe);
152		cx25840_write(client, 0x164, gpio_da);
153	}
154
155	return check_fw_load(client, size);
156}
157
158MODULE_FIRMWARE(CX2388x_FIRMWARE);
159MODULE_FIRMWARE(CX231xx_FIRMWARE);
160MODULE_FIRMWARE(CX25840_FIRMWARE);
161
162