xref: /linux/drivers/media/radio/radio-zoltrix.c (revision 0e9ab8e4d44ae9d9aaf213bfd2c90bbe7289337b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Zoltrix Radio Plus driver
4  * Copyright 1998 C. van Schaik <carl@leg.uct.ac.za>
5  *
6  * BUGS
7  *  Due to the inconsistency in reading from the signal flags
8  *  it is difficult to get an accurate tuned signal.
9  *
10  *  It seems that the card is not linear to 0 volume. It cuts off
11  *  at a low volume, and it is not possible (at least I have not found)
12  *  to get fine volume control over the low volume range.
13  *
14  *  Some code derived from code by Romolo Manfredini
15  *				   romolo@bicnet.it
16  *
17  * 1999-05-06 - (C. van Schaik)
18  *	      - Make signal strength and stereo scans
19  *		kinder to cpu while in delay
20  * 1999-01-05 - (C. van Schaik)
21  *	      - Changed tuning to 1/160Mhz accuracy
22  *	      - Added stereo support
23  *		(card defaults to stereo)
24  *		(can explicitly force mono on the card)
25  *		(can detect if station is in stereo)
26  *	      - Added unmute function
27  *	      - Reworked ioctl functions
28  * 2002-07-15 - Fix Stereo typo
29  *
30  * 2006-07-24 - Converted to V4L2 API
31  *		by Mauro Carvalho Chehab <mchehab@kernel.org>
32  *
33  * Converted to the radio-isa framework by Hans Verkuil <hans.verkuil@cisco.com>
34  *
35  * Note that this is the driver for the Zoltrix Radio Plus.
36  * This driver does not work for the Zoltrix Radio Plus 108 or the
37  * Zoltrix Radio Plus for Windows.
38  *
39  * Fully tested with the Keene USB FM Transmitter and the v4l2-compliance tool.
40  */
41 
42 #include <linux/module.h>	/* Modules                        */
43 #include <linux/init.h>		/* Initdata                       */
44 #include <linux/ioport.h>	/* request_region		  */
45 #include <linux/delay.h>	/* udelay, msleep                 */
46 #include <linux/videodev2.h>	/* kernel radio structs           */
47 #include <linux/mutex.h>
48 #include <linux/io.h>		/* outb, outb_p                   */
49 #include <linux/slab.h>
50 #include <media/v4l2-device.h>
51 #include <media/v4l2-ioctl.h>
52 #include "radio-isa.h"
53 
54 MODULE_AUTHOR("C. van Schaik");
55 MODULE_DESCRIPTION("A driver for the Zoltrix Radio Plus.");
56 MODULE_LICENSE("GPL");
57 MODULE_VERSION("0.1.99");
58 
59 #ifndef CONFIG_RADIO_ZOLTRIX_PORT
60 #define CONFIG_RADIO_ZOLTRIX_PORT -1
61 #endif
62 
63 #define ZOLTRIX_MAX 2
64 
65 static int io[ZOLTRIX_MAX] = { [0] = CONFIG_RADIO_ZOLTRIX_PORT,
66 			       [1 ... (ZOLTRIX_MAX - 1)] = -1 };
67 static int radio_nr[ZOLTRIX_MAX] = { [0 ... (ZOLTRIX_MAX - 1)] = -1 };
68 
69 module_param_array(io, int, NULL, 0444);
70 MODULE_PARM_DESC(io, "I/O addresses of the Zoltrix Radio Plus card (0x20c or 0x30c)");
71 module_param_array(radio_nr, int, NULL, 0444);
72 MODULE_PARM_DESC(radio_nr, "Radio device numbers");
73 
74 struct zoltrix {
75 	struct radio_isa_card isa;
76 	int curvol;
77 	bool muted;
78 };
79 
80 static struct radio_isa_card *zoltrix_alloc(void)
81 {
82 	struct zoltrix *zol = kzalloc(sizeof(*zol), GFP_KERNEL);
83 
84 	return zol ? &zol->isa : NULL;
85 }
86 
87 static int zoltrix_s_mute_volume(struct radio_isa_card *isa, bool mute, int vol)
88 {
89 	struct zoltrix *zol = container_of(isa, struct zoltrix, isa);
90 
91 	zol->curvol = vol;
92 	zol->muted = mute;
93 	if (mute || vol == 0) {
94 		outb(0, isa->io);
95 		outb(0, isa->io);
96 		inb(isa->io + 3);            /* Zoltrix needs to be read to confirm */
97 		return 0;
98 	}
99 
100 	outb(vol - 1, isa->io);
101 	msleep(10);
102 	inb(isa->io + 2);
103 	return 0;
104 }
105 
106 /* tunes the radio to the desired frequency */
107 static int zoltrix_s_frequency(struct radio_isa_card *isa, u32 freq)
108 {
109 	struct zoltrix *zol = container_of(isa, struct zoltrix, isa);
110 	struct v4l2_device *v4l2_dev = &isa->v4l2_dev;
111 	unsigned long long bitmask, f, m;
112 	bool stereo = isa->stereo;
113 	int i;
114 
115 	if (freq == 0) {
116 		v4l2_warn(v4l2_dev, "cannot set a frequency of 0.\n");
117 		return -EINVAL;
118 	}
119 
120 	m = (freq / 160 - 8800) * 2;
121 	f = (unsigned long long)m + 0x4d1c;
122 
123 	bitmask = 0xc480402c10080000ull;
124 	i = 45;
125 
126 	outb(0, isa->io);
127 	outb(0, isa->io);
128 	inb(isa->io + 3);            /* Zoltrix needs to be read to confirm */
129 
130 	outb(0x40, isa->io);
131 	outb(0xc0, isa->io);
132 
133 	bitmask = (bitmask ^ ((f & 0xff) << 47) ^ ((f & 0xff00) << 30) ^ (stereo << 31));
134 	while (i--) {
135 		if ((bitmask & 0x8000000000000000ull) != 0) {
136 			outb(0x80, isa->io);
137 			udelay(50);
138 			outb(0x00, isa->io);
139 			udelay(50);
140 			outb(0x80, isa->io);
141 			udelay(50);
142 		} else {
143 			outb(0xc0, isa->io);
144 			udelay(50);
145 			outb(0x40, isa->io);
146 			udelay(50);
147 			outb(0xc0, isa->io);
148 			udelay(50);
149 		}
150 		bitmask *= 2;
151 	}
152 	/* termination sequence */
153 	outb(0x80, isa->io);
154 	outb(0xc0, isa->io);
155 	outb(0x40, isa->io);
156 	udelay(1000);
157 	inb(isa->io + 2);
158 	udelay(1000);
159 
160 	return zoltrix_s_mute_volume(isa, zol->muted, zol->curvol);
161 }
162 
163 /* Get signal strength */
164 static u32 zoltrix_g_rxsubchans(struct radio_isa_card *isa)
165 {
166 	struct zoltrix *zol = container_of(isa, struct zoltrix, isa);
167 	int a, b;
168 
169 	outb(0x00, isa->io);         /* This stuff I found to do nothing */
170 	outb(zol->curvol, isa->io);
171 	msleep(20);
172 
173 	a = inb(isa->io);
174 	msleep(10);
175 	b = inb(isa->io);
176 
177 	return (a == b && a == 0xcf) ?
178 		V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO;
179 }
180 
181 static u32 zoltrix_g_signal(struct radio_isa_card *isa)
182 {
183 	struct zoltrix *zol = container_of(isa, struct zoltrix, isa);
184 	int a, b;
185 
186 	outb(0x00, isa->io);         /* This stuff I found to do nothing */
187 	outb(zol->curvol, isa->io);
188 	msleep(20);
189 
190 	a = inb(isa->io);
191 	msleep(10);
192 	b = inb(isa->io);
193 
194 	if (a != b)
195 		return 0;
196 
197 	/* I found this out by playing with a binary scanner on the card io */
198 	return (a == 0xcf || a == 0xdf || a == 0xef) ? 0xffff : 0;
199 }
200 
201 static int zoltrix_s_stereo(struct radio_isa_card *isa, bool stereo)
202 {
203 	return zoltrix_s_frequency(isa, isa->freq);
204 }
205 
206 static const struct radio_isa_ops zoltrix_ops = {
207 	.alloc = zoltrix_alloc,
208 	.s_mute_volume = zoltrix_s_mute_volume,
209 	.s_frequency = zoltrix_s_frequency,
210 	.s_stereo = zoltrix_s_stereo,
211 	.g_rxsubchans = zoltrix_g_rxsubchans,
212 	.g_signal = zoltrix_g_signal,
213 };
214 
215 static const int zoltrix_ioports[] = { 0x20c, 0x30c };
216 
217 static struct radio_isa_driver zoltrix_driver = {
218 	.driver = {
219 		.match		= radio_isa_match,
220 		.probe		= radio_isa_probe,
221 		.remove		= radio_isa_remove,
222 		.driver		= {
223 			.name	= "radio-zoltrix",
224 		},
225 	},
226 	.io_params = io,
227 	.radio_nr_params = radio_nr,
228 	.io_ports = zoltrix_ioports,
229 	.num_of_io_ports = ARRAY_SIZE(zoltrix_ioports),
230 	.region_size = 2,
231 	.card = "Zoltrix Radio Plus",
232 	.ops = &zoltrix_ops,
233 	.has_stereo = true,
234 	.max_volume = 15,
235 };
236 
237 static int __init zoltrix_init(void)
238 {
239 	return isa_register_driver(&zoltrix_driver.driver, ZOLTRIX_MAX);
240 }
241 
242 static void __exit zoltrix_exit(void)
243 {
244 	isa_unregister_driver(&zoltrix_driver.driver);
245 }
246 
247 module_init(zoltrix_init);
248 module_exit(zoltrix_exit);
249 
250