/*
   *
   * Hardware accelerated Matrox Millennium I, II, Mystique, G100, G200, G400 and G450.
   *
   * (c) 1998-2002 Petr Vandrovec <vandrove@vc.cvut.cz>
   *
   * Version: 1.64 2002/06/10
   *
   * See matroxfb_base.c for contributors.
   *
   */
  
  #include "matroxfb_base.h"
  #include "matroxfb_maven.h"
  #include <linux/i2c.h>
  #include <linux/slab.h>
  #include <linux/i2c-algo-bit.h>
  
  /* MGA-TVO I2C for G200, G400 */
  #define MAT_CLK		0x20
  #define MAT_DATA	0x10
  /* primary head DDC for Mystique(?), G100, G200, G400 */
  #define DDC1_CLK	0x08
  #define DDC1_DATA	0x02
  /* primary head DDC for Millennium, Millennium II */
  #define DDC1B_CLK	0x10
  #define DDC1B_DATA	0x04
  /* secondary head DDC for G400 */
  #define DDC2_CLK	0x04
  #define DDC2_DATA	0x01
  
  /******************************************************/
  
  struct matroxfb_dh_maven_info {
  	struct i2c_bit_adapter	maven;
  	struct i2c_bit_adapter	ddc1;
  	struct i2c_bit_adapter	ddc2;
  };
  
  static int matroxfb_read_gpio(struct matrox_fb_info* minfo) {
  	unsigned long flags;
  	int v;
  
  	matroxfb_DAC_lock_irqsave(flags);
  	v = matroxfb_DAC_in(minfo, DAC_XGENIODATA);
  	matroxfb_DAC_unlock_irqrestore(flags);
  	return v;
  }
  
  static void matroxfb_set_gpio(struct matrox_fb_info* minfo, int mask, int val) {
  	unsigned long flags;
  	int v;
  
  	matroxfb_DAC_lock_irqsave(flags);
  	v = (matroxfb_DAC_in(minfo, DAC_XGENIOCTRL) & mask) | val;
  	matroxfb_DAC_out(minfo, DAC_XGENIOCTRL, v);
  	/* We must reset GENIODATA very often... XFree plays with this register */
  	matroxfb_DAC_out(minfo, DAC_XGENIODATA, 0x00);
  	matroxfb_DAC_unlock_irqrestore(flags);
  }
  
  /* software I2C functions */
  static inline void matroxfb_i2c_set(struct matrox_fb_info* minfo, int mask, int state) {
  	if (state)
  		state = 0;
  	else
  		state = mask;
  	matroxfb_set_gpio(minfo, ~mask, state);
  }
  
  static void matroxfb_gpio_setsda(void* data, int state) {
  	struct i2c_bit_adapter* b = data;
  	matroxfb_i2c_set(b->minfo, b->mask.data, state);
  }
  
  static void matroxfb_gpio_setscl(void* data, int state) {
  	struct i2c_bit_adapter* b = data;
  	matroxfb_i2c_set(b->minfo, b->mask.clock, state);
  }
  
  static int matroxfb_gpio_getsda(void* data) {
  	struct i2c_bit_adapter* b = data;
  	return (matroxfb_read_gpio(b->minfo) & b->mask.data) ? 1 : 0;
  }
  
  static int matroxfb_gpio_getscl(void* data) {
  	struct i2c_bit_adapter* b = data;
  	return (matroxfb_read_gpio(b->minfo) & b->mask.clock) ? 1 : 0;
  }
  
  static const struct i2c_algo_bit_data matrox_i2c_algo_template =
  {
  	.setsda		= matroxfb_gpio_setsda,
  	.setscl		= matroxfb_gpio_setscl,
  	.getsda		= matroxfb_gpio_getsda,
  	.getscl		= matroxfb_gpio_getscl,
  	.udelay		= 10,
  	.timeout	= 100,
  };
  
  static int i2c_bus_reg(struct i2c_bit_adapter* b, struct matrox_fb_info* minfo, 
  		unsigned int data, unsigned int clock, const char *name,
  		int class)
  {
  	int err;
  
  	b->minfo = minfo;
  	b->mask.data = data;
  	b->mask.clock = clock;
  	b->adapter.owner = THIS_MODULE;
  	snprintf(b->adapter.name, sizeof(b->adapter.name), name,
  		minfo->fbcon.node);
  	i2c_set_adapdata(&b->adapter, b);
  	b->adapter.class = class;
  	b->adapter.algo_data = &b->bac;
  	b->adapter.dev.parent = &minfo->pcidev->dev;
  	b->bac = matrox_i2c_algo_template;
  	b->bac.data = b;
  	err = i2c_bit_add_bus(&b->adapter);
  	b->initialized = !err;
  	return err;
  }
  
  static void i2c_bit_bus_del(struct i2c_bit_adapter* b) {
  	if (b->initialized) {
  		i2c_del_adapter(&b->adapter);
  		b->initialized = 0;
  	}
  }
  
  static inline void i2c_maven_done(struct matroxfb_dh_maven_info* minfo2) {
  	i2c_bit_bus_del(&minfo2->maven);
  }
  
  static inline void i2c_ddc1_done(struct matroxfb_dh_maven_info* minfo2) {
  	i2c_bit_bus_del(&minfo2->ddc1);
  }
  
  static inline void i2c_ddc2_done(struct matroxfb_dh_maven_info* minfo2) {
  	i2c_bit_bus_del(&minfo2->ddc2);
  }
  
  static void* i2c_matroxfb_probe(struct matrox_fb_info* minfo) {
  	int err;
  	unsigned long flags;
  	struct matroxfb_dh_maven_info* m2info;
  
  	m2info = kzalloc(sizeof(*m2info), GFP_KERNEL);
  	if (!m2info)
  		return NULL;
  
  	matroxfb_DAC_lock_irqsave(flags);
  	matroxfb_DAC_out(minfo, DAC_XGENIODATA, 0xFF);
  	matroxfb_DAC_out(minfo, DAC_XGENIOCTRL, 0x00);
  	matroxfb_DAC_unlock_irqrestore(flags);
  
  	switch (minfo->chip) {
  		case MGA_2064:
  		case MGA_2164:
  			err = i2c_bus_reg(&m2info->ddc1, minfo,
  					  DDC1B_DATA, DDC1B_CLK,
  					  "DDC:fb%u #0", I2C_CLASS_DDC);
  			break;
  		default:
  			err = i2c_bus_reg(&m2info->ddc1, minfo,
  					  DDC1_DATA, DDC1_CLK,
  					  "DDC:fb%u #0", I2C_CLASS_DDC);
  			break;
  	}
  	if (err)
  		goto fail_ddc1;
  	if (minfo->devflags.dualhead) {
  		err = i2c_bus_reg(&m2info->ddc2, minfo,
  				  DDC2_DATA, DDC2_CLK,
  				  "DDC:fb%u #1", I2C_CLASS_DDC);
  		if (err == -ENODEV) {
  			printk(KERN_INFO "i2c-matroxfb: VGA->TV plug detected, DDC unavailable.
  ");
  		} else if (err)
  			printk(KERN_INFO "i2c-matroxfb: Could not register secondary output i2c bus. Continuing anyway.
  ");
  		/* Register maven bus even on G450/G550 */
  		err = i2c_bus_reg(&m2info->maven, minfo,
  				  MAT_DATA, MAT_CLK, "MAVEN:fb%u", 0);
  		if (err)
  			printk(KERN_INFO "i2c-matroxfb: Could not register Maven i2c bus. Continuing anyway.
  ");
  		else {
  			struct i2c_board_info maven_info = {
  				I2C_BOARD_INFO("maven", 0x1b),
  			};
  			unsigned short const addr_list[2] = {
  				0x1b, I2C_CLIENT_END
  			};
  
  			i2c_new_probed_device(&m2info->maven.adapter,
  					      &maven_info, addr_list, NULL);
  		}
  	}
  	return m2info;
  fail_ddc1:;
  	kfree(m2info);
  	printk(KERN_ERR "i2c-matroxfb: Could not register primary adapter DDC bus.
  ");
  	return NULL;
  }
  
  static void i2c_matroxfb_remove(struct matrox_fb_info* minfo, void* data) {
  	struct matroxfb_dh_maven_info* m2info = data;
  
  	i2c_maven_done(m2info);
  	i2c_ddc2_done(m2info);
  	i2c_ddc1_done(m2info);
  	kfree(m2info);
  }
  
  static struct matroxfb_driver i2c_matroxfb = {
  	.node =		LIST_HEAD_INIT(i2c_matroxfb.node),
  	.name =		"i2c-matroxfb",
  	.probe = 	i2c_matroxfb_probe,
  	.remove =	i2c_matroxfb_remove,
  };
  
  static int __init i2c_matroxfb_init(void) {
  	if (matroxfb_register_driver(&i2c_matroxfb)) {
  		printk(KERN_ERR "i2c-matroxfb: failed to register driver
  ");
  		return -ENXIO;
  	}
  	return 0;
  }
  
  static void __exit i2c_matroxfb_exit(void) {
  	matroxfb_unregister_driver(&i2c_matroxfb);
  }
  
  MODULE_AUTHOR("(c) 1999-2002 Petr Vandrovec <vandrove@vc.cvut.cz>");
  MODULE_DESCRIPTION("Support module providing I2C buses present on Matrox videocards");
  
  module_init(i2c_matroxfb_init);
  module_exit(i2c_matroxfb_exit);
  /* no __setup required */
  MODULE_LICENSE("GPL");