/* radio-trust.c - Trust FM Radio card driver for Linux 2.2
   * by Eric Lammerts <eric@scintilla.utwente.nl>
   *
   * Based on radio-aztech.c. Original notes:
   *
   * Adapted to support the Video for Linux API by
   * Russell Kroll <rkroll@exploits.org>.  Based on original tuner code by:
   *
   * Quay Ly
   * Donald Song
   * Jason Lewis      (jlewis@twilight.vtc.vsc.edu)
   * Scott McGrath    (smcgrath@twilight.vtc.vsc.edu)
   * William McGrath  (wmcgrath@twilight.vtc.vsc.edu)
   *
   * Converted to V4L2 API by Mauro Carvalho Chehab <mchehab@infradead.org>
   */
  
  #include <stdarg.h>
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/ioport.h>
  #include <linux/videodev2.h>
  #include <linux/io.h>
  #include <linux/slab.h>
  #include <media/v4l2-device.h>
  #include <media/v4l2-ioctl.h>
  #include "radio-isa.h"
  
  MODULE_AUTHOR("Eric Lammerts, Russell Kroll, Quay Lu, Donald Song, Jason Lewis, Scott McGrath, William McGrath");
  MODULE_DESCRIPTION("A driver for the Trust FM Radio card.");
  MODULE_LICENSE("GPL");
  MODULE_VERSION("0.1.99");
  
  /* acceptable ports: 0x350 (JP3 shorted), 0x358 (JP3 open) */
  
  #ifndef CONFIG_RADIO_TRUST_PORT
  #define CONFIG_RADIO_TRUST_PORT -1
  #endif
  
  #define TRUST_MAX 2
  
  static int io[TRUST_MAX] = { [0] = CONFIG_RADIO_TRUST_PORT,
  			      [1 ... (TRUST_MAX - 1)] = -1 };
  static int radio_nr[TRUST_MAX] = { [0 ... (TRUST_MAX - 1)] = -1 };
  
  module_param_array(io, int, NULL, 0444);
  MODULE_PARM_DESC(io, "I/O addresses of the Trust FM Radio card (0x350 or 0x358)");
  module_param_array(radio_nr, int, NULL, 0444);
  MODULE_PARM_DESC(radio_nr, "Radio device numbers");
  
  struct trust {
  	struct radio_isa_card isa;
  	int ioval;
  };
  
  static struct radio_isa_card *trust_alloc(void)
  {
  	struct trust *tr = kzalloc(sizeof(*tr), GFP_KERNEL);
  
  	return tr ? &tr->isa : NULL;
  }
  
  /* i2c addresses */
  #define TDA7318_ADDR 0x88
  #define TSA6060T_ADDR 0xc4
  
  #define TR_DELAY do { inb(tr->isa.io); inb(tr->isa.io); inb(tr->isa.io); } while (0)
  #define TR_SET_SCL outb(tr->ioval |= 2, tr->isa.io)
  #define TR_CLR_SCL outb(tr->ioval &= 0xfd, tr->isa.io)
  #define TR_SET_SDA outb(tr->ioval |= 1, tr->isa.io)
  #define TR_CLR_SDA outb(tr->ioval &= 0xfe, tr->isa.io)
  
  static void write_i2c(struct trust *tr, int n, ...)
  {
  	unsigned char val, mask;
  	va_list args;
  
  	va_start(args, n);
  
  	/* start condition */
  	TR_SET_SDA;
  	TR_SET_SCL;
  	TR_DELAY;
  	TR_CLR_SDA;
  	TR_CLR_SCL;
  	TR_DELAY;
  
  	for (; n; n--) {
  		val = va_arg(args, unsigned);
  		for (mask = 0x80; mask; mask >>= 1) {
  			if (val & mask)
  				TR_SET_SDA;
  			else
  				TR_CLR_SDA;
  			TR_SET_SCL;
  			TR_DELAY;
  			TR_CLR_SCL;
  			TR_DELAY;
  		}
  		/* acknowledge bit */
  		TR_SET_SDA;
  		TR_SET_SCL;
  		TR_DELAY;
  		TR_CLR_SCL;
  		TR_DELAY;
  	}
  
  	/* stop condition */
  	TR_CLR_SDA;
  	TR_DELAY;
  	TR_SET_SCL;
  	TR_DELAY;
  	TR_SET_SDA;
  	TR_DELAY;
  
  	va_end(args);
  }
  
  static int trust_s_mute_volume(struct radio_isa_card *isa, bool mute, int vol)
  {
  	struct trust *tr = container_of(isa, struct trust, isa);
  
  	tr->ioval = (tr->ioval & 0xf7) | (mute << 3);
  	outb(tr->ioval, isa->io);
  	write_i2c(tr, 2, TDA7318_ADDR, vol ^ 0x1f);
  	return 0;
  }
  
  static int trust_s_stereo(struct radio_isa_card *isa, bool stereo)
  {
  	struct trust *tr = container_of(isa, struct trust, isa);
  
  	tr->ioval = (tr->ioval & 0xfb) | (!stereo << 2);
  	outb(tr->ioval, isa->io);
  	return 0;
  }
  
  static u32 trust_g_signal(struct radio_isa_card *isa)
  {
  	int i, v;
  
  	for (i = 0, v = 0; i < 100; i++)
  		v |= inb(isa->io);
  	return (v & 1) ? 0 : 0xffff;
  }
  
  static int trust_s_frequency(struct radio_isa_card *isa, u32 freq)
  {
  	struct trust *tr = container_of(isa, struct trust, isa);
  
  	freq /= 160;	/* Convert to 10 kHz units	*/
  	freq += 1070;	/* Add 10.7 MHz IF		*/
  	write_i2c(tr, 5, TSA6060T_ADDR, (freq << 1) | 1,
  			freq >> 7, 0x60 | ((freq >> 15) & 1), 0);
  	return 0;
  }
  
  static int basstreble2chip[15] = {
  	0, 1, 2, 3, 4, 5, 6, 7, 14, 13, 12, 11, 10, 9, 8
  };
  
  static int trust_s_ctrl(struct v4l2_ctrl *ctrl)
  {
  	struct radio_isa_card *isa =
  		container_of(ctrl->handler, struct radio_isa_card, hdl);
  	struct trust *tr = container_of(isa, struct trust, isa);
  
  	switch (ctrl->id) {
  	case V4L2_CID_AUDIO_BASS:
  		write_i2c(tr, 2, TDA7318_ADDR, 0x60 | basstreble2chip[ctrl->val]);
  		return 0;
  	case V4L2_CID_AUDIO_TREBLE:
  		write_i2c(tr, 2, TDA7318_ADDR, 0x70 | basstreble2chip[ctrl->val]);
  		return 0;
  	}
  	return -EINVAL;
  }
  
  static const struct v4l2_ctrl_ops trust_ctrl_ops = {
  	.s_ctrl = trust_s_ctrl,
  };
  
  static int trust_initialize(struct radio_isa_card *isa)
  {
  	struct trust *tr = container_of(isa, struct trust, isa);
  
  	tr->ioval = 0xf;
  	write_i2c(tr, 2, TDA7318_ADDR, 0x80);	/* speaker att. LF = 0 dB */
  	write_i2c(tr, 2, TDA7318_ADDR, 0xa0);	/* speaker att. RF = 0 dB */
  	write_i2c(tr, 2, TDA7318_ADDR, 0xc0);	/* speaker att. LR = 0 dB */
  	write_i2c(tr, 2, TDA7318_ADDR, 0xe0);	/* speaker att. RR = 0 dB */
  	write_i2c(tr, 2, TDA7318_ADDR, 0x40);	/* stereo 1 input, gain = 18.75 dB */
  
  	v4l2_ctrl_new_std(&isa->hdl, &trust_ctrl_ops,
  				V4L2_CID_AUDIO_BASS, 0, 15, 1, 8);
  	v4l2_ctrl_new_std(&isa->hdl, &trust_ctrl_ops,
  				V4L2_CID_AUDIO_TREBLE, 0, 15, 1, 8);
  	return isa->hdl.error;
  }
  
  static const struct radio_isa_ops trust_ops = {
  	.init = trust_initialize,
  	.alloc = trust_alloc,
  	.s_mute_volume = trust_s_mute_volume,
  	.s_frequency = trust_s_frequency,
  	.s_stereo = trust_s_stereo,
  	.g_signal = trust_g_signal,
  };
  
  static const int trust_ioports[] = { 0x350, 0x358 };
  
  static struct radio_isa_driver trust_driver = {
  	.driver = {
  		.match		= radio_isa_match,
  		.probe		= radio_isa_probe,
  		.remove		= radio_isa_remove,
  		.driver		= {
  			.name	= "radio-trust",
  		},
  	},
  	.io_params = io,
  	.radio_nr_params = radio_nr,
  	.io_ports = trust_ioports,
  	.num_of_io_ports = ARRAY_SIZE(trust_ioports),
  	.region_size = 2,
  	.card = "Trust FM Radio",
  	.ops = &trust_ops,
  	.has_stereo = true,
  	.max_volume = 31,
  };
  
  static int __init trust_init(void)
  {
  	return isa_register_driver(&trust_driver.driver, TRUST_MAX);
  }
  
  static void __exit trust_exit(void)
  {
  	isa_unregister_driver(&trust_driver.driver);
  }
  
  module_init(trust_init);
  module_exit(trust_exit);