text: /*
      i2c Support for the Apple `Hydra' Mac I/O
  
      Copyright (c) 1999-2004 Geert Uytterhoeven <geert@linux-m68k.org>
  
      Based on i2c Support for Via Technologies 82C586B South Bridge
      Copyright (c) 1998, 1999 Kyösti Mälkki <kmalkki@cc.hut.fi>
  
      This program is free software; you can redistribute it and/or modify
      it under the terms of the GNU General Public License as published by
      the Free Software Foundation; either version 2 of the License, or
      (at your option) any later version.
  
      This program is distributed in the hope that it will be useful,
      but WITHOUT ANY WARRANTY; without even the implied warranty of
      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      GNU General Public License for more details.
  */
  
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/pci.h>
  #include <linux/types.h>
  #include <linux/i2c.h>
  #include <linux/i2c-algo-bit.h>
  #include <linux/io.h>
  #include <asm/hydra.h>
  
  
  #define HYDRA_CPD_PD0	0x00000001	/* CachePD lines */
  #define HYDRA_CPD_PD1	0x00000002
  #define HYDRA_CPD_PD2	0x00000004
  #define HYDRA_CPD_PD3	0x00000008
  
  #define HYDRA_SCLK	HYDRA_CPD_PD0
  #define HYDRA_SDAT	HYDRA_CPD_PD1
  #define HYDRA_SCLK_OE	0x00000010
  #define HYDRA_SDAT_OE	0x00000020
  
  static inline void pdregw(void *data, u32 val)
  {
  	struct Hydra *hydra = (struct Hydra *)data;
  	writel(val, &hydra->CachePD);
  }
  
  static inline u32 pdregr(void *data)
  {
  	struct Hydra *hydra = (struct Hydra *)data;
  	return readl(&hydra->CachePD);
  }
  
  static void hydra_bit_setscl(void *data, int state)
  {
  	u32 val = pdregr(data);
  	if (state)
  		val &= ~HYDRA_SCLK_OE;
  	else {
  		val &= ~HYDRA_SCLK;
  		val |= HYDRA_SCLK_OE;
  	}
  	pdregw(data, val);
  }
  
  static void hydra_bit_setsda(void *data, int state)
  {
  	u32 val = pdregr(data);
  	if (state)
  		val &= ~HYDRA_SDAT_OE;
  	else {
  		val &= ~HYDRA_SDAT;
  		val |= HYDRA_SDAT_OE;
  	}
  	pdregw(data, val);
  }
  
  static int hydra_bit_getscl(void *data)
  {
  	return (pdregr(data) & HYDRA_SCLK) != 0;
  }
  
  static int hydra_bit_getsda(void *data)
  {
  	return (pdregr(data) & HYDRA_SDAT) != 0;
  }
  
  /* ------------------------------------------------------------------------ */
  
  static struct i2c_algo_bit_data hydra_bit_data = {
  	.setsda		= hydra_bit_setsda,
  	.setscl		= hydra_bit_setscl,
  	.getsda		= hydra_bit_getsda,
  	.getscl		= hydra_bit_getscl,
  	.udelay		= 5,
  	.timeout	= HZ
  };
  
  static struct i2c_adapter hydra_adap = {
  	.owner		= THIS_MODULE,
  	.name		= "Hydra i2c",
  	.algo_data	= &hydra_bit_data,
  };
  
  static const struct pci_device_id hydra_ids[] = {
  	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_HYDRA) },
  	{ 0, }
  };
  
  MODULE_DEVICE_TABLE (pci, hydra_ids);
  
  static int hydra_probe(struct pci_dev *dev,
  				 const struct pci_device_id *id)
  {
  	unsigned long base = pci_resource_start(dev, 0);
  	int res;
  
  	if (!request_mem_region(base+offsetof(struct Hydra, CachePD), 4,
  				hydra_adap.name))
  		return -EBUSY;
  
  	hydra_bit_data.data = pci_ioremap_bar(dev, 0);
  	if (hydra_bit_data.data == NULL) {
  		release_mem_region(base+offsetof(struct Hydra, CachePD), 4);
  		return -ENODEV;
  	}
  
  	pdregw(hydra_bit_data.data, 0);		/* clear SCLK_OE and SDAT_OE */
  	hydra_adap.dev.parent = &dev->dev;
  	res = i2c_bit_add_bus(&hydra_adap);
  	if (res < 0) {
  		iounmap(hydra_bit_data.data);
  		release_mem_region(base+offsetof(struct Hydra, CachePD), 4);
  		return res;
  	}
  	return 0;
  }
  
  static void hydra_remove(struct pci_dev *dev)
  {
  	pdregw(hydra_bit_data.data, 0);		/* clear SCLK_OE and SDAT_OE */
  	i2c_del_adapter(&hydra_adap);
  	iounmap(hydra_bit_data.data);
  	release_mem_region(pci_resource_start(dev, 0)+
  			   offsetof(struct Hydra, CachePD), 4);
  }
  
  
  static struct pci_driver hydra_driver = {
  	.name		= "hydra_smbus",
  	.id_table	= hydra_ids,
  	.probe		= hydra_probe,
  	.remove		= hydra_remove,
  };
  
  module_pci_driver(hydra_driver);
  
  MODULE_AUTHOR("Geert Uytterhoeven <geert@linux-m68k.org>");
  MODULE_DESCRIPTION("i2c for Apple Hydra Mac I/O");
  MODULE_LICENSE("GPL");
  