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diff --git a/drivers/media/radio/radio-typhoon.c b/drivers/media/radio/radio-typhoon.c
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+// SPDX-License-Identifier: GPL-2.0-only
+/* Typhoon Radio Card driver for radio support
+ * (c) 1999 Dr. Henrik Seidel <Henrik.Seidel@gmx.de>
+ *
+ * Notes on the hardware
+ *
+ * This card has two output sockets, one for speakers and one for line.
+ * The speaker output has volume control, but only in four discrete
+ * steps. The line output has neither volume control nor mute.
+ *
+ * The card has auto-stereo according to its manual, although it all
+ * sounds mono to me (even with the Win/DOS drivers). Maybe it's my
+ * antenna - I really don't know for sure.
+ *
+ * Frequency control is done digitally.
+ *
+ * Volume control is done digitally, but there are only four different
+ * possible values. So you should better always turn the volume up and
+ * use line control. I got the best results by connecting line output
+ * to the sound card microphone input. For such a configuration the
+ * volume control has no effect, since volume control only influences
+ * the speaker output.
+ *
+ * There is no explicit mute/unmute. So I set the radio frequency to a
+ * value where I do expect just noise and turn the speaker volume down.
+ * The frequency change is necessary since the card never seems to be
+ * completely silent.
+ *
+ * Converted to V4L2 API by Mauro Carvalho Chehab <mchehab@kernel.org>
+ */
+
+#include <linux/module.h> /* Modules */
+#include <linux/init.h> /* Initdata */
+#include <linux/ioport.h> /* request_region */
+#include <linux/videodev2.h> /* kernel radio structs */
+#include <linux/io.h> /* outb, outb_p */
+#include <linux/slab.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-ioctl.h>
+#include "radio-isa.h"
+
+#define DRIVER_VERSION "0.1.2"
+
+MODULE_AUTHOR("Dr. Henrik Seidel");
+MODULE_DESCRIPTION("A driver for the Typhoon radio card (a.k.a. EcoRadio).");
+MODULE_LICENSE("GPL");
+MODULE_VERSION("0.1.99");
+
+#ifndef CONFIG_RADIO_TYPHOON_PORT
+#define CONFIG_RADIO_TYPHOON_PORT -1
+#endif
+
+#ifndef CONFIG_RADIO_TYPHOON_MUTEFREQ
+#define CONFIG_RADIO_TYPHOON_MUTEFREQ 87000
+#endif
+
+#define TYPHOON_MAX 2
+
+static int io[TYPHOON_MAX] = { [0] = CONFIG_RADIO_TYPHOON_PORT,
+ [1 ... (TYPHOON_MAX - 1)] = -1 };
+static int radio_nr[TYPHOON_MAX] = { [0 ... (TYPHOON_MAX - 1)] = -1 };
+static unsigned long mutefreq = CONFIG_RADIO_TYPHOON_MUTEFREQ;
+
+module_param_array(io, int, NULL, 0444);
+MODULE_PARM_DESC(io, "I/O addresses of the Typhoon card (0x316 or 0x336)");
+module_param_array(radio_nr, int, NULL, 0444);
+MODULE_PARM_DESC(radio_nr, "Radio device numbers");
+module_param(mutefreq, ulong, 0);
+MODULE_PARM_DESC(mutefreq, "Frequency used when muting the card (in kHz)");
+
+struct typhoon {
+ struct radio_isa_card isa;
+ int muted;
+};
+
+static struct radio_isa_card *typhoon_alloc(void)
+{
+ struct typhoon *ty = kzalloc(sizeof(*ty), GFP_KERNEL);
+
+ return ty ? &ty->isa : NULL;
+}
+
+static int typhoon_s_frequency(struct radio_isa_card *isa, u32 freq)
+{
+ unsigned long outval;
+ unsigned long x;
+
+ /*
+ * The frequency transfer curve is not linear. The best fit I could
+ * get is
+ *
+ * outval = -155 + exp((f + 15.55) * 0.057))
+ *
+ * where frequency f is in MHz. Since we don't have exp in the kernel,
+ * I approximate this function by a third order polynomial.
+ *
+ */
+
+ x = freq / 160;
+ outval = (x * x + 2500) / 5000;
+ outval = (outval * x + 5000) / 10000;
+ outval -= (10 * x * x + 10433) / 20866;
+ outval += 4 * x - 11505;
+
+ outb_p((outval >> 8) & 0x01, isa->io + 4);
+ outb_p(outval >> 9, isa->io + 6);
+ outb_p(outval & 0xff, isa->io + 8);
+ return 0;
+}
+
+static int typhoon_s_mute_volume(struct radio_isa_card *isa, bool mute, int vol)
+{
+ struct typhoon *ty = container_of(isa, struct typhoon, isa);
+
+ if (mute)
+ vol = 0;
+ vol >>= 14; /* Map 16 bit to 2 bit */
+ vol &= 3;
+ outb_p(vol / 2, isa->io); /* Set the volume, high bit. */
+ outb_p(vol % 2, isa->io + 2); /* Set the volume, low bit. */
+
+ if (vol == 0 && !ty->muted) {
+ ty->muted = true;
+ return typhoon_s_frequency(isa, mutefreq << 4);
+ }
+ if (vol && ty->muted) {
+ ty->muted = false;
+ return typhoon_s_frequency(isa, isa->freq);
+ }
+ return 0;
+}
+
+static const struct radio_isa_ops typhoon_ops = {
+ .alloc = typhoon_alloc,
+ .s_mute_volume = typhoon_s_mute_volume,
+ .s_frequency = typhoon_s_frequency,
+};
+
+static const int typhoon_ioports[] = { 0x316, 0x336 };
+
+static struct radio_isa_driver typhoon_driver = {
+ .driver = {
+ .match = radio_isa_match,
+ .probe = radio_isa_probe,
+ .remove = radio_isa_remove,
+ .driver = {
+ .name = "radio-typhoon",
+ },
+ },
+ .io_params = io,
+ .radio_nr_params = radio_nr,
+ .io_ports = typhoon_ioports,
+ .num_of_io_ports = ARRAY_SIZE(typhoon_ioports),
+ .region_size = 8,
+ .card = "Typhoon Radio",
+ .ops = &typhoon_ops,
+ .has_stereo = true,
+ .max_volume = 3,
+};
+
+static int __init typhoon_init(void)
+{
+ if (mutefreq < 87000 || mutefreq > 108000) {
+ printk(KERN_ERR "%s: You must set a frequency (in kHz) used when muting the card,\n",
+ typhoon_driver.driver.driver.name);
+ printk(KERN_ERR "%s: e.g. with \"mutefreq=87500\" (87000 <= mutefreq <= 108000)\n",
+ typhoon_driver.driver.driver.name);
+ return -ENODEV;
+ }
+ return isa_register_driver(&typhoon_driver.driver, TYPHOON_MAX);
+}
+
+static void __exit typhoon_exit(void)
+{
+ isa_unregister_driver(&typhoon_driver.driver);
+}
+
+
+module_init(typhoon_init);
+module_exit(typhoon_exit);
+