1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * GemTek radio card driver
4  *
5  * Copyright 1998 Jonas Munsin <jmunsin@iki.fi>
6  *
7  * GemTek hasn't released any specs on the card, so the protocol had to
8  * be reverse engineered with dosemu.
9  *
10  * Besides the protocol changes, this is mostly a copy of:
11  *
12  *    RadioTrack II driver for Linux radio support (C) 1998 Ben Pfaff
13  *
14  *    Based on RadioTrack I/RadioReveal (C) 1997 M. Kirkwood
15  *    Converted to new API by Alan Cox <alan@lxorguk.ukuu.org.uk>
16  *    Various bugfixes and enhancements by Russell Kroll <rkroll@exploits.org>
17  *
18  * Converted to the radio-isa framework by Hans Verkuil <hans.verkuil@cisco.com>
19  * Converted to V4L2 API by Mauro Carvalho Chehab <mchehab@kernel.org>
20  *
21  * Note: this card seems to swap the left and right audio channels!
22  *
23  * Fully tested with the Keene USB FM Transmitter and the v4l2-compliance tool.
24  */
25 
26 #include <linux/module.h>	/* Modules			*/
27 #include <linux/init.h>		/* Initdata			*/
28 #include <linux/ioport.h>	/* request_region		*/
29 #include <linux/delay.h>	/* udelay			*/
30 #include <linux/videodev2.h>	/* kernel radio structs		*/
31 #include <linux/mutex.h>
32 #include <linux/io.h>		/* outb, outb_p			*/
33 #include <linux/pnp.h>
34 #include <linux/slab.h>
35 #include <media/v4l2-ioctl.h>
36 #include <media/v4l2-device.h>
37 #include "radio-isa.h"
38 
39 /*
40  * Module info.
41  */
42 
43 MODULE_AUTHOR("Jonas Munsin, Pekka Seppänen <pexu@kapsi.fi>");
44 MODULE_DESCRIPTION("A driver for the GemTek Radio card.");
45 MODULE_LICENSE("GPL");
46 MODULE_VERSION("1.0.0");
47 
48 /*
49  * Module params.
50  */
51 
52 #ifndef CONFIG_RADIO_GEMTEK_PORT
53 #define CONFIG_RADIO_GEMTEK_PORT -1
54 #endif
55 #ifndef CONFIG_RADIO_GEMTEK_PROBE
56 #define CONFIG_RADIO_GEMTEK_PROBE 1
57 #endif
58 
59 #define GEMTEK_MAX 4
60 
61 static bool probe = CONFIG_RADIO_GEMTEK_PROBE;
62 static bool hardmute;
63 static int io[GEMTEK_MAX] = { [0] = CONFIG_RADIO_GEMTEK_PORT,
64 			      [1 ... (GEMTEK_MAX - 1)] = -1 };
65 static int radio_nr[GEMTEK_MAX]	= { [0 ... (GEMTEK_MAX - 1)] = -1 };
66 
67 module_param(probe, bool, 0444);
68 MODULE_PARM_DESC(probe, "Enable automatic device probing.");
69 
70 module_param(hardmute, bool, 0644);
71 MODULE_PARM_DESC(hardmute, "Enable 'hard muting' by shutting down PLL, may reduce static noise.");
72 
73 module_param_array(io, int, NULL, 0444);
74 MODULE_PARM_DESC(io, "Force I/O ports for the GemTek Radio card if automatic probing is disabled or fails. The most common I/O ports are: 0x20c 0x30c, 0x24c or 0x34c (0x20c, 0x248 and 0x28c have been reported to work for the combined sound/radiocard).");
75 
76 module_param_array(radio_nr, int, NULL, 0444);
77 MODULE_PARM_DESC(radio_nr, "Radio device numbers");
78 
79 /*
80  * Frequency calculation constants.  Intermediate frequency 10.52 MHz (nominal
81  * value 10.7 MHz), reference divisor 6.39 kHz (nominal 6.25 kHz).
82  */
83 #define FSCALE		8
84 #define IF_OFFSET	((unsigned int)(10.52 * 16000 * (1<<FSCALE)))
85 #define REF_FREQ	((unsigned int)(6.39 * 16 * (1<<FSCALE)))
86 
87 #define GEMTEK_CK		0x01	/* Clock signal			*/
88 #define GEMTEK_DA		0x02	/* Serial data			*/
89 #define GEMTEK_CE		0x04	/* Chip enable			*/
90 #define GEMTEK_NS		0x08	/* No signal			*/
91 #define GEMTEK_MT		0x10	/* Line mute			*/
92 #define GEMTEK_STDF_3_125_KHZ	0x01	/* Standard frequency 3.125 kHz	*/
93 #define GEMTEK_PLL_OFF		0x07	/* PLL off			*/
94 
95 #define BU2614_BUS_SIZE	32	/* BU2614 / BU2614FS bus size		*/
96 
97 #define SHORT_DELAY 5		/* usec */
98 #define LONG_DELAY 75		/* usec */
99 
100 struct gemtek {
101 	struct radio_isa_card isa;
102 	bool muted;
103 	u32 bu2614data;
104 };
105 
106 #define BU2614_FREQ_BITS	16 /* D0..D15, Frequency data		*/
107 #define BU2614_PORT_BITS	3 /* P0..P2, Output port control data	*/
108 #define BU2614_VOID_BITS	4 /* unused				*/
109 #define BU2614_FMES_BITS	1 /* CT, Frequency measurement beginning data */
110 #define BU2614_STDF_BITS	3 /* R0..R2, Standard frequency data	*/
111 #define BU2614_SWIN_BITS	1 /* S, Switch between FMIN / AMIN	*/
112 #define BU2614_SWAL_BITS        1 /* PS, Swallow counter division (AMIN only)*/
113 #define BU2614_VOID2_BITS	1 /* unused				*/
114 #define BU2614_FMUN_BITS	1 /* GT, Frequency measurement time & unlock */
115 #define BU2614_TEST_BITS	1 /* TS, Test data is input		*/
116 
117 #define BU2614_FREQ_SHIFT	0
118 #define BU2614_PORT_SHIFT	(BU2614_FREQ_BITS + BU2614_FREQ_SHIFT)
119 #define BU2614_VOID_SHIFT	(BU2614_PORT_BITS + BU2614_PORT_SHIFT)
120 #define BU2614_FMES_SHIFT	(BU2614_VOID_BITS + BU2614_VOID_SHIFT)
121 #define BU2614_STDF_SHIFT	(BU2614_FMES_BITS + BU2614_FMES_SHIFT)
122 #define BU2614_SWIN_SHIFT	(BU2614_STDF_BITS + BU2614_STDF_SHIFT)
123 #define BU2614_SWAL_SHIFT	(BU2614_SWIN_BITS + BU2614_SWIN_SHIFT)
124 #define BU2614_VOID2_SHIFT	(BU2614_SWAL_BITS + BU2614_SWAL_SHIFT)
125 #define BU2614_FMUN_SHIFT	(BU2614_VOID2_BITS + BU2614_VOID2_SHIFT)
126 #define BU2614_TEST_SHIFT	(BU2614_FMUN_BITS + BU2614_FMUN_SHIFT)
127 
128 #define MKMASK(field)	(((1UL<<BU2614_##field##_BITS) - 1) << \
129 			BU2614_##field##_SHIFT)
130 #define BU2614_PORT_MASK	MKMASK(PORT)
131 #define BU2614_FREQ_MASK	MKMASK(FREQ)
132 #define BU2614_VOID_MASK	MKMASK(VOID)
133 #define BU2614_FMES_MASK	MKMASK(FMES)
134 #define BU2614_STDF_MASK	MKMASK(STDF)
135 #define BU2614_SWIN_MASK	MKMASK(SWIN)
136 #define BU2614_SWAL_MASK	MKMASK(SWAL)
137 #define BU2614_VOID2_MASK	MKMASK(VOID2)
138 #define BU2614_FMUN_MASK	MKMASK(FMUN)
139 #define BU2614_TEST_MASK	MKMASK(TEST)
140 
141 /*
142  * Set data which will be sent to BU2614FS.
143  */
144 #define gemtek_bu2614_set(dev, field, data) ((dev)->bu2614data = \
145 	((dev)->bu2614data & ~field##_MASK) | ((data) << field##_SHIFT))
146 
147 /*
148  * Transmit settings to BU2614FS over GemTek IC.
149  */
gemtek_bu2614_transmit(struct gemtek * gt)150 static void gemtek_bu2614_transmit(struct gemtek *gt)
151 {
152 	struct radio_isa_card *isa = &gt->isa;
153 	int i, bit, q, mute;
154 
155 	mute = gt->muted ? GEMTEK_MT : 0x00;
156 
157 	outb_p(mute | GEMTEK_CE | GEMTEK_DA | GEMTEK_CK, isa->io);
158 	udelay(LONG_DELAY);
159 
160 	for (i = 0, q = gt->bu2614data; i < 32; i++, q >>= 1) {
161 		bit = (q & 1) ? GEMTEK_DA : 0;
162 		outb_p(mute | GEMTEK_CE | bit, isa->io);
163 		udelay(SHORT_DELAY);
164 		outb_p(mute | GEMTEK_CE | bit | GEMTEK_CK, isa->io);
165 		udelay(SHORT_DELAY);
166 	}
167 
168 	outb_p(mute | GEMTEK_DA | GEMTEK_CK, isa->io);
169 	udelay(SHORT_DELAY);
170 }
171 
172 /*
173  * Calculate divisor from FM-frequency for BU2614FS (3.125 KHz STDF expected).
174  */
gemtek_convfreq(unsigned long freq)175 static unsigned long gemtek_convfreq(unsigned long freq)
176 {
177 	return ((freq << FSCALE) + IF_OFFSET + REF_FREQ / 2) / REF_FREQ;
178 }
179 
gemtek_alloc(void)180 static struct radio_isa_card *gemtek_alloc(void)
181 {
182 	struct gemtek *gt = kzalloc(sizeof(*gt), GFP_KERNEL);
183 
184 	if (gt)
185 		gt->muted = true;
186 	return gt ? &gt->isa : NULL;
187 }
188 
189 /*
190  * Set FM-frequency.
191  */
gemtek_s_frequency(struct radio_isa_card * isa,u32 freq)192 static int gemtek_s_frequency(struct radio_isa_card *isa, u32 freq)
193 {
194 	struct gemtek *gt = container_of(isa, struct gemtek, isa);
195 
196 	if (hardmute && gt->muted)
197 		return 0;
198 
199 	gemtek_bu2614_set(gt, BU2614_PORT, 0);
200 	gemtek_bu2614_set(gt, BU2614_FMES, 0);
201 	gemtek_bu2614_set(gt, BU2614_SWIN, 0);	/* FM-mode	*/
202 	gemtek_bu2614_set(gt, BU2614_SWAL, 0);
203 	gemtek_bu2614_set(gt, BU2614_FMUN, 1);	/* GT bit set	*/
204 	gemtek_bu2614_set(gt, BU2614_TEST, 0);
205 	gemtek_bu2614_set(gt, BU2614_STDF, GEMTEK_STDF_3_125_KHZ);
206 	gemtek_bu2614_set(gt, BU2614_FREQ, gemtek_convfreq(freq));
207 	gemtek_bu2614_transmit(gt);
208 	return 0;
209 }
210 
211 /*
212  * Set mute flag.
213  */
gemtek_s_mute_volume(struct radio_isa_card * isa,bool mute,int vol)214 static int gemtek_s_mute_volume(struct radio_isa_card *isa, bool mute, int vol)
215 {
216 	struct gemtek *gt = container_of(isa, struct gemtek, isa);
217 	int i;
218 
219 	gt->muted = mute;
220 	if (hardmute) {
221 		if (!mute)
222 			return gemtek_s_frequency(isa, isa->freq);
223 
224 		/* Turn off PLL, disable data output */
225 		gemtek_bu2614_set(gt, BU2614_PORT, 0);
226 		gemtek_bu2614_set(gt, BU2614_FMES, 0);	/* CT bit off	*/
227 		gemtek_bu2614_set(gt, BU2614_SWIN, 0);	/* FM-mode	*/
228 		gemtek_bu2614_set(gt, BU2614_SWAL, 0);
229 		gemtek_bu2614_set(gt, BU2614_FMUN, 0);	/* GT bit off	*/
230 		gemtek_bu2614_set(gt, BU2614_TEST, 0);
231 		gemtek_bu2614_set(gt, BU2614_STDF, GEMTEK_PLL_OFF);
232 		gemtek_bu2614_set(gt, BU2614_FREQ, 0);
233 		gemtek_bu2614_transmit(gt);
234 		return 0;
235 	}
236 
237 	/* Read bus contents (CE, CK and DA). */
238 	i = inb_p(isa->io);
239 	/* Write it back with mute flag set. */
240 	outb_p((i >> 5) | (mute ? GEMTEK_MT : 0), isa->io);
241 	udelay(SHORT_DELAY);
242 	return 0;
243 }
244 
gemtek_g_rxsubchans(struct radio_isa_card * isa)245 static u32 gemtek_g_rxsubchans(struct radio_isa_card *isa)
246 {
247 	if (inb_p(isa->io) & GEMTEK_NS)
248 		return V4L2_TUNER_SUB_MONO;
249 	return V4L2_TUNER_SUB_STEREO;
250 }
251 
252 /*
253  * Check if requested card acts like GemTek Radio card.
254  */
gemtek_probe(struct radio_isa_card * isa,int io)255 static bool gemtek_probe(struct radio_isa_card *isa, int io)
256 {
257 	int i, q;
258 
259 	q = inb_p(io);	/* Read bus contents before probing. */
260 	/* Try to turn on CE, CK and DA respectively and check if card responds
261 	   properly. */
262 	for (i = 0; i < 3; ++i) {
263 		outb_p(1 << i, io);
264 		udelay(SHORT_DELAY);
265 
266 		if ((inb_p(io) & ~GEMTEK_NS) != (0x17 | (1 << (i + 5))))
267 			return false;
268 	}
269 	outb_p(q >> 5, io);	/* Write bus contents back. */
270 	udelay(SHORT_DELAY);
271 	return true;
272 }
273 
274 static const struct radio_isa_ops gemtek_ops = {
275 	.alloc = gemtek_alloc,
276 	.probe = gemtek_probe,
277 	.s_mute_volume = gemtek_s_mute_volume,
278 	.s_frequency = gemtek_s_frequency,
279 	.g_rxsubchans = gemtek_g_rxsubchans,
280 };
281 
282 static const int gemtek_ioports[] = { 0x20c, 0x30c, 0x24c, 0x34c, 0x248, 0x28c };
283 
284 #ifdef CONFIG_PNP
285 static const struct pnp_device_id gemtek_pnp_devices[] = {
286 	/* AOpen FX-3D/Pro Radio */
287 	{.id = "ADS7183", .driver_data = 0},
288 	{.id = ""}
289 };
290 
291 MODULE_DEVICE_TABLE(pnp, gemtek_pnp_devices);
292 #endif
293 
294 static struct radio_isa_driver gemtek_driver = {
295 	.driver = {
296 		.match		= radio_isa_match,
297 		.probe		= radio_isa_probe,
298 		.remove		= radio_isa_remove,
299 		.driver		= {
300 			.name	= "radio-gemtek",
301 		},
302 	},
303 #ifdef CONFIG_PNP
304 	.pnp_driver = {
305 		.name		= "radio-gemtek",
306 		.id_table	= gemtek_pnp_devices,
307 		.probe		= radio_isa_pnp_probe,
308 		.remove		= radio_isa_pnp_remove,
309 	},
310 #endif
311 	.io_params = io,
312 	.radio_nr_params = radio_nr,
313 	.io_ports = gemtek_ioports,
314 	.num_of_io_ports = ARRAY_SIZE(gemtek_ioports),
315 	.region_size = 1,
316 	.card = "GemTek Radio",
317 	.ops = &gemtek_ops,
318 	.has_stereo = true,
319 };
320 
gemtek_init(void)321 static int __init gemtek_init(void)
322 {
323 	gemtek_driver.probe = probe;
324 #ifdef CONFIG_PNP
325 	pnp_register_driver(&gemtek_driver.pnp_driver);
326 #endif
327 	return isa_register_driver(&gemtek_driver.driver, GEMTEK_MAX);
328 }
329 
gemtek_exit(void)330 static void __exit gemtek_exit(void)
331 {
332 	hardmute = true;	/* Turn off PLL */
333 #ifdef CONFIG_PNP
334 	pnp_unregister_driver(&gemtek_driver.pnp_driver);
335 #endif
336 	isa_unregister_driver(&gemtek_driver.driver);
337 }
338 
339 module_init(gemtek_init);
340 module_exit(gemtek_exit);
341