radio-zoltrix.c

  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 <hverkuil@kernel.org>
 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
 54MODULE_AUTHOR("C. van Schaik");
 55MODULE_DESCRIPTION("A driver for the Zoltrix Radio Plus.");
 56MODULE_LICENSE("GPL");
 57MODULE_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
 65static int io[ZOLTRIX_MAX] = { [0] = CONFIG_RADIO_ZOLTRIX_PORT,
 66			       [1 ... (ZOLTRIX_MAX - 1)] = -1 };
 67static int radio_nr[ZOLTRIX_MAX] = { [0 ... (ZOLTRIX_MAX - 1)] = -1 };
 68
 69module_param_array(io, int, NULL, 0444);
 70MODULE_PARM_DESC(io, "I/O addresses of the Zoltrix Radio Plus card (0x20c or 0x30c)");
 71module_param_array(radio_nr, int, NULL, 0444);
 72MODULE_PARM_DESC(radio_nr, "Radio device numbers");
 73
 74struct zoltrix {
 75	struct radio_isa_card isa;
 76	int curvol;
 77	bool muted;
 78};
 79
 80static 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
 87static 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 */
107static 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 */
164static 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
181static 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
201static int zoltrix_s_stereo(struct radio_isa_card *isa, bool stereo)
202{
203	return zoltrix_s_frequency(isa, isa->freq);
204}
205
206static 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
215static const int zoltrix_ioports[] = { 0x20c, 0x30c };
216
217static 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
237static int __init zoltrix_init(void)
238{
239	return isa_register_driver(&zoltrix_driver.driver, ZOLTRIX_MAX);
240}
241
242static void __exit zoltrix_exit(void)
243{
244	isa_unregister_driver(&zoltrix_driver.driver);
245}
246
247module_init(zoltrix_init);
248module_exit(zoltrix_exit);
249