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