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 <linux/pnp.h>
33 #include <linux/slab.h>
34 #include <media/v4l2-ioctl.h>
35 #include <media/v4l2-device.h>
36 #include "radio-isa.h"
37 
38 /*
39  * Module info.
40  */
41 
42 MODULE_AUTHOR("Jonas Munsin, Pekka Seppänen <pexu@kapsi.fi>");
43 MODULE_DESCRIPTION("A driver for the GemTek Radio card.");
44 MODULE_LICENSE("GPL");
45 MODULE_VERSION("1.0.0");
46 
47 /*
48  * Module params.
49  */
50 
51 #ifndef CONFIG_RADIO_GEMTEK_PORT
52 #define CONFIG_RADIO_GEMTEK_PORT -1
53 #endif
54 #ifndef CONFIG_RADIO_GEMTEK_PROBE
55 #define CONFIG_RADIO_GEMTEK_PROBE 1
56 #endif
57 
58 #define GEMTEK_MAX 4
59 
60 static bool probe = CONFIG_RADIO_GEMTEK_PROBE;
61 static bool hardmute;
62 static int io[GEMTEK_MAX] = { [0] = CONFIG_RADIO_GEMTEK_PORT,
63 			      [1 ... (GEMTEK_MAX - 1)] = -1 };
64 static int radio_nr[GEMTEK_MAX]	= { [0 ... (GEMTEK_MAX - 1)] = -1 };
65 
66 module_param(probe, bool, 0444);
67 MODULE_PARM_DESC(probe, "Enable automatic device probing.");
68 
69 module_param(hardmute, bool, 0644);
70 MODULE_PARM_DESC(hardmute, "Enable 'hard muting' by shutting down PLL, may "
71 	 "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 "
75 	 "probing is disabled or fails. The most common I/O ports are: 0x20c "
76 	 "0x30c, 0x24c or 0x34c (0x20c, 0x248 and 0x28c have been reported to "
77 	 "work for the combined sound/radiocard).");
78 
79 module_param_array(radio_nr, int, NULL, 0444);
80 MODULE_PARM_DESC(radio_nr, "Radio device numbers");
81 
82 /*
83  * Frequency calculation constants.  Intermediate frequency 10.52 MHz (nominal
84  * value 10.7 MHz), reference divisor 6.39 kHz (nominal 6.25 kHz).
85  */
86 #define FSCALE		8
87 #define IF_OFFSET	((unsigned int)(10.52 * 16000 * (1<<FSCALE)))
88 #define REF_FREQ	((unsigned int)(6.39 * 16 * (1<<FSCALE)))
89 
90 #define GEMTEK_CK		0x01	/* Clock signal			*/
91 #define GEMTEK_DA		0x02	/* Serial data			*/
92 #define GEMTEK_CE		0x04	/* Chip enable			*/
93 #define GEMTEK_NS		0x08	/* No signal			*/
94 #define GEMTEK_MT		0x10	/* Line mute			*/
95 #define GEMTEK_STDF_3_125_KHZ	0x01	/* Standard frequency 3.125 kHz	*/
96 #define GEMTEK_PLL_OFF		0x07	/* PLL off			*/
97 
98 #define BU2614_BUS_SIZE	32	/* BU2614 / BU2614FS bus size		*/
99 
100 #define SHORT_DELAY 5		/* usec */
101 #define LONG_DELAY 75		/* usec */
102 
103 struct gemtek {
104 	struct radio_isa_card isa;
105 	bool muted;
106 	u32 bu2614data;
107 };
108 
109 #define BU2614_FREQ_BITS 	16 /* D0..D15, Frequency data		*/
110 #define BU2614_PORT_BITS	3 /* P0..P2, Output port control data	*/
111 #define BU2614_VOID_BITS	4 /* unused 				*/
112 #define BU2614_FMES_BITS	1 /* CT, Frequency measurement beginning data */
113 #define BU2614_STDF_BITS	3 /* R0..R2, Standard frequency data	*/
114 #define BU2614_SWIN_BITS	1 /* S, Switch between FMIN / AMIN	*/
115 #define BU2614_SWAL_BITS        1 /* PS, Swallow counter division (AMIN only)*/
116 #define BU2614_VOID2_BITS	1 /* unused				*/
117 #define BU2614_FMUN_BITS	1 /* GT, Frequency measurement time & unlock */
118 #define BU2614_TEST_BITS	1 /* TS, Test data is input		*/
119 
120 #define BU2614_FREQ_SHIFT 	0
121 #define BU2614_PORT_SHIFT	(BU2614_FREQ_BITS + BU2614_FREQ_SHIFT)
122 #define BU2614_VOID_SHIFT	(BU2614_PORT_BITS + BU2614_PORT_SHIFT)
123 #define BU2614_FMES_SHIFT	(BU2614_VOID_BITS + BU2614_VOID_SHIFT)
124 #define BU2614_STDF_SHIFT	(BU2614_FMES_BITS + BU2614_FMES_SHIFT)
125 #define BU2614_SWIN_SHIFT	(BU2614_STDF_BITS + BU2614_STDF_SHIFT)
126 #define BU2614_SWAL_SHIFT	(BU2614_SWIN_BITS + BU2614_SWIN_SHIFT)
127 #define BU2614_VOID2_SHIFT	(BU2614_SWAL_BITS + BU2614_SWAL_SHIFT)
128 #define BU2614_FMUN_SHIFT	(BU2614_VOID2_BITS + BU2614_VOID2_SHIFT)
129 #define BU2614_TEST_SHIFT	(BU2614_FMUN_BITS + BU2614_FMUN_SHIFT)
130 
131 #define MKMASK(field)	(((1<<BU2614_##field##_BITS) - 1) << \
132 			BU2614_##field##_SHIFT)
133 #define BU2614_PORT_MASK	MKMASK(PORT)
134 #define BU2614_FREQ_MASK	MKMASK(FREQ)
135 #define BU2614_VOID_MASK	MKMASK(VOID)
136 #define BU2614_FMES_MASK	MKMASK(FMES)
137 #define BU2614_STDF_MASK	MKMASK(STDF)
138 #define BU2614_SWIN_MASK	MKMASK(SWIN)
139 #define BU2614_SWAL_MASK	MKMASK(SWAL)
140 #define BU2614_VOID2_MASK	MKMASK(VOID2)
141 #define BU2614_FMUN_MASK	MKMASK(FMUN)
142 #define BU2614_TEST_MASK	MKMASK(TEST)
143 
144 /*
145  * Set data which will be sent to BU2614FS.
146  */
147 #define gemtek_bu2614_set(dev, field, data) ((dev)->bu2614data = \
148 	((dev)->bu2614data & ~field##_MASK) | ((data) << field##_SHIFT))
149 
150 /*
151  * Transmit settings to BU2614FS over GemTek IC.
152  */
153 static void gemtek_bu2614_transmit(struct gemtek *gt)
154 {
155 	struct radio_isa_card *isa = &gt->isa;
156 	int i, bit, q, mute;
157 
158 	mute = gt->muted ? GEMTEK_MT : 0x00;
159 
160 	outb_p(mute | GEMTEK_CE | GEMTEK_DA | GEMTEK_CK, isa->io);
161 	udelay(LONG_DELAY);
162 
163 	for (i = 0, q = gt->bu2614data; i < 32; i++, q >>= 1) {
164 		bit = (q & 1) ? GEMTEK_DA : 0;
165 		outb_p(mute | GEMTEK_CE | bit, isa->io);
166 		udelay(SHORT_DELAY);
167 		outb_p(mute | GEMTEK_CE | bit | GEMTEK_CK, isa->io);
168 		udelay(SHORT_DELAY);
169 	}
170 
171 	outb_p(mute | GEMTEK_DA | GEMTEK_CK, isa->io);
172 	udelay(SHORT_DELAY);
173 }
174 
175 /*
176  * Calculate divisor from FM-frequency for BU2614FS (3.125 KHz STDF expected).
177  */
178 static unsigned long gemtek_convfreq(unsigned long freq)
179 {
180 	return ((freq << FSCALE) + IF_OFFSET + REF_FREQ / 2) / REF_FREQ;
181 }
182 
183 static struct radio_isa_card *gemtek_alloc(void)
184 {
185 	struct gemtek *gt = kzalloc(sizeof(*gt), GFP_KERNEL);
186 
187 	if (gt)
188 		gt->muted = true;
189 	return gt ? &gt->isa : NULL;
190 }
191 
192 /*
193  * Set FM-frequency.
194  */
195 static int gemtek_s_frequency(struct radio_isa_card *isa, u32 freq)
196 {
197 	struct gemtek *gt = container_of(isa, struct gemtek, isa);
198 
199 	if (hardmute && gt->muted)
200 		return 0;
201 
202 	gemtek_bu2614_set(gt, BU2614_PORT, 0);
203 	gemtek_bu2614_set(gt, BU2614_FMES, 0);
204 	gemtek_bu2614_set(gt, BU2614_SWIN, 0);	/* FM-mode	*/
205 	gemtek_bu2614_set(gt, BU2614_SWAL, 0);
206 	gemtek_bu2614_set(gt, BU2614_FMUN, 1);	/* GT bit set	*/
207 	gemtek_bu2614_set(gt, BU2614_TEST, 0);
208 	gemtek_bu2614_set(gt, BU2614_STDF, GEMTEK_STDF_3_125_KHZ);
209 	gemtek_bu2614_set(gt, BU2614_FREQ, gemtek_convfreq(freq));
210 	gemtek_bu2614_transmit(gt);
211 	return 0;
212 }
213 
214 /*
215  * Set mute flag.
216  */
217 static int gemtek_s_mute_volume(struct radio_isa_card *isa, bool mute, int vol)
218 {
219 	struct gemtek *gt = container_of(isa, struct gemtek, isa);
220 	int i;
221 
222 	gt->muted = mute;
223 	if (hardmute) {
224 		if (!mute)
225 			return gemtek_s_frequency(isa, isa->freq);
226 
227 		/* Turn off PLL, disable data output */
228 		gemtek_bu2614_set(gt, BU2614_PORT, 0);
229 		gemtek_bu2614_set(gt, BU2614_FMES, 0);	/* CT bit off	*/
230 		gemtek_bu2614_set(gt, BU2614_SWIN, 0);	/* FM-mode	*/
231 		gemtek_bu2614_set(gt, BU2614_SWAL, 0);
232 		gemtek_bu2614_set(gt, BU2614_FMUN, 0);	/* GT bit off	*/
233 		gemtek_bu2614_set(gt, BU2614_TEST, 0);
234 		gemtek_bu2614_set(gt, BU2614_STDF, GEMTEK_PLL_OFF);
235 		gemtek_bu2614_set(gt, BU2614_FREQ, 0);
236 		gemtek_bu2614_transmit(gt);
237 		return 0;
238 	}
239 
240 	/* Read bus contents (CE, CK and DA). */
241 	i = inb_p(isa->io);
242 	/* Write it back with mute flag set. */
243 	outb_p((i >> 5) | (mute ? GEMTEK_MT : 0), isa->io);
244 	udelay(SHORT_DELAY);
245 	return 0;
246 }
247 
248 static u32 gemtek_g_rxsubchans(struct radio_isa_card *isa)
249 {
250 	if (inb_p(isa->io) & GEMTEK_NS)
251 		return V4L2_TUNER_SUB_MONO;
252 	return V4L2_TUNER_SUB_STEREO;
253 }
254 
255 /*
256  * Check if requested card acts like GemTek Radio card.
257  */
258 static bool gemtek_probe(struct radio_isa_card *isa, int io)
259 {
260 	int i, q;
261 
262 	q = inb_p(io);	/* Read bus contents before probing. */
263 	/* Try to turn on CE, CK and DA respectively and check if card responds
264 	   properly. */
265 	for (i = 0; i < 3; ++i) {
266 		outb_p(1 << i, io);
267 		udelay(SHORT_DELAY);
268 
269 		if ((inb_p(io) & ~GEMTEK_NS) != (0x17 | (1 << (i + 5))))
270 			return false;
271 	}
272 	outb_p(q >> 5, io);	/* Write bus contents back. */
273 	udelay(SHORT_DELAY);
274 	return true;
275 }
276 
277 static const struct radio_isa_ops gemtek_ops = {
278 	.alloc = gemtek_alloc,
279 	.probe = gemtek_probe,
280 	.s_mute_volume = gemtek_s_mute_volume,
281 	.s_frequency = gemtek_s_frequency,
282 	.g_rxsubchans = gemtek_g_rxsubchans,
283 };
284 
285 static const int gemtek_ioports[] = { 0x20c, 0x30c, 0x24c, 0x34c, 0x248, 0x28c };
286 
287 #ifdef CONFIG_PNP
288 static struct pnp_device_id gemtek_pnp_devices[] = {
289 	/* AOpen FX-3D/Pro Radio */
290 	{.id = "ADS7183", .driver_data = 0},
291 	{.id = ""}
292 };
293 
294 MODULE_DEVICE_TABLE(pnp, gemtek_pnp_devices);
295 #endif
296 
297 static struct radio_isa_driver gemtek_driver = {
298 	.driver = {
299 		.match		= radio_isa_match,
300 		.probe		= radio_isa_probe,
301 		.remove		= radio_isa_remove,
302 		.driver		= {
303 			.name	= "radio-gemtek",
304 		},
305 	},
306 #ifdef CONFIG_PNP
307 	.pnp_driver = {
308 		.name		= "radio-gemtek",
309 		.id_table	= gemtek_pnp_devices,
310 		.probe		= radio_isa_pnp_probe,
311 		.remove		= radio_isa_pnp_remove,
312 	},
313 #endif
314 	.io_params = io,
315 	.radio_nr_params = radio_nr,
316 	.io_ports = gemtek_ioports,
317 	.num_of_io_ports = ARRAY_SIZE(gemtek_ioports),
318 	.region_size = 1,
319 	.card = "GemTek Radio",
320 	.ops = &gemtek_ops,
321 	.has_stereo = true,
322 };
323 
324 static int __init gemtek_init(void)
325 {
326 	gemtek_driver.probe = probe;
327 #ifdef CONFIG_PNP
328 	pnp_register_driver(&gemtek_driver.pnp_driver);
329 #endif
330 	return isa_register_driver(&gemtek_driver.driver, GEMTEK_MAX);
331 }
332 
333 static void __exit gemtek_exit(void)
334 {
335 	hardmute = 1;	/* Turn off PLL */
336 #ifdef CONFIG_PNP
337 	pnp_unregister_driver(&gemtek_driver.pnp_driver);
338 #endif
339 	isa_unregister_driver(&gemtek_driver.driver);
340 }
341 
342 module_init(gemtek_init);
343 module_exit(gemtek_exit);
344