// SPDX-License-Identifier: GPL-2.0-only

  /*
   * Windfarm PowerMac thermal control. LM75 sensor
   *
   * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
   *                    <benh@kernel.crashing.org>

   */
  
  #include <linux/types.h>
  #include <linux/errno.h>
  #include <linux/kernel.h>
  #include <linux/delay.h>
  #include <linux/slab.h>
  #include <linux/init.h>
  #include <linux/wait.h>
  #include <linux/i2c.h>

  #include <linux/of_device.h>

  #include <asm/prom.h>
  #include <asm/machdep.h>
  #include <asm/io.h>

  #include <asm/sections.h>

  #include <asm/pmac_low_i2c.h>

  
  #include "windfarm.h"

  #define VERSION "1.0"

  
  #undef DEBUG
  
  #ifdef DEBUG
  #define DBG(args...)	printk(args)
  #else
  #define DBG(args...)	do { } while(0)
  #endif
  
  struct wf_lm75_sensor {
  	int			ds1775 : 1;
  	int			inited : 1;

  	struct i2c_client	*i2c;
  	struct wf_sensor	sens;

  };
  #define wf_to_lm75(c) container_of(c, struct wf_lm75_sensor, sens)

  
  static int wf_lm75_get(struct wf_sensor *sr, s32 *value)
  {
  	struct wf_lm75_sensor *lm = wf_to_lm75(sr);
  	s32 data;

  	if (lm->i2c == NULL)

  		return -ENODEV;
  
  	/* Init chip if necessary */
  	if (!lm->inited) {

  		u8 cfg_new, cfg = (u8)i2c_smbus_read_byte_data(lm->i2c, 1);

  
  		DBG("wf_lm75: Initializing %s, cfg was: %02x
  ",
  		    sr->name, cfg);
  
  		/* clear shutdown bit, keep other settings as left by
  		 * the firmware for now
  		 */
  		cfg_new = cfg & ~0x01;

  		i2c_smbus_write_byte_data(lm->i2c, 1, cfg_new);

  		lm->inited = 1;
  
  		/* If we just powered it up, let's wait 200 ms */
  		msleep(200);
  	}
  
  	/* Read temperature register */

  	data = (s32)le16_to_cpu(i2c_smbus_read_word_data(lm->i2c, 0));

  	data <<= 8;
  	*value = data;
  
  	return 0;
  }
  
  static void wf_lm75_release(struct wf_sensor *sr)
  {
  	struct wf_lm75_sensor *lm = wf_to_lm75(sr);

  	kfree(lm);
  }

  static const struct wf_sensor_ops wf_lm75_ops = {

  	.get_value	= wf_lm75_get,
  	.release	= wf_lm75_release,
  	.owner		= THIS_MODULE,
  };

  static int wf_lm75_probe(struct i2c_client *client,
  			 const struct i2c_device_id *id)

  {	

  	struct wf_lm75_sensor *lm;

  	int rc, ds1775;

  	const char *name, *loc;

  	if (id)
  		ds1775 = id->driver_data;
  	else
  		ds1775 = !!of_device_get_match_data(&client->dev);

  	DBG("wf_lm75: creating  %s device at address 0x%02x
  ",

  	    ds1775 ? "ds1775" : "lm75", client->addr);
  
  	loc = of_get_property(client->dev.of_node, "hwsensor-location", NULL);
  	if (!loc) {
  		dev_warn(&client->dev, "Missing hwsensor-location property!
  ");
  		return -ENXIO;
  	}

  
  	/* Usual rant about sensor names not beeing very consistent in
  	 * the device-tree, oh well ...
  	 * Add more entries below as you deal with more setups
  	 */
  	if (!strcmp(loc, "Hard drive") || !strcmp(loc, "DRIVE BAY"))

  		name = "hd-temp";

  	else if (!strcmp(loc, "Incoming Air Temp"))

  		name = "incoming-air-temp";

  	else if (!strcmp(loc, "ODD Temp"))

  		name = "optical-drive-temp";

  	else if (!strcmp(loc, "HD Temp"))

  		name = "hard-drive-temp";

  	else if (!strcmp(loc, "PCI SLOTS"))
  		name = "slots-temp";
  	else if (!strcmp(loc, "CPU A INLET"))
  		name = "cpu-inlet-temp-0";
  	else if (!strcmp(loc, "CPU B INLET"))
  		name = "cpu-inlet-temp-1";

  	else

  		return -ENXIO;
   	

  	lm = kzalloc(sizeof(struct wf_lm75_sensor), GFP_KERNEL);
  	if (lm == NULL)

  		return -ENODEV;

  	lm->inited = 0;
  	lm->ds1775 = ds1775;
  	lm->i2c = client;

  	lm->sens.name = name;

  	lm->sens.ops = &wf_lm75_ops;
  	i2c_set_clientdata(client, lm);

  	rc = wf_register_sensor(&lm->sens);
  	if (rc)
  		kfree(lm);
  	return rc;

  }

  static int wf_lm75_remove(struct i2c_client *client)

  {

  	struct wf_lm75_sensor *lm = i2c_get_clientdata(client);

  	/* Mark client detached */

  	lm->i2c = NULL;

  
  	/* release sensor */
  	wf_unregister_sensor(&lm->sens);
  
  	return 0;
  }

  static const struct i2c_device_id wf_lm75_id[] = {

  	{ "MAC,lm75", 0 },
  	{ "MAC,ds1775", 1 },

  	{ }
  };

  MODULE_DEVICE_TABLE(i2c, wf_lm75_id);

  static const struct of_device_id wf_lm75_of_id[] = {
  	{ .compatible = "lm75", .data = (void *)0},
  	{ .compatible = "ds1775", .data = (void *)1 },
  	{ }
  };
  MODULE_DEVICE_TABLE(of, wf_lm75_of_id);

  static struct i2c_driver wf_lm75_driver = {
  	.driver = {
  		.name	= "wf_lm75",

  		.of_match_table = wf_lm75_of_id,

  	},

  	.probe		= wf_lm75_probe,
  	.remove		= wf_lm75_remove,
  	.id_table	= wf_lm75_id,
  };

  module_i2c_driver(wf_lm75_driver);

  
  MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
  MODULE_DESCRIPTION("LM75 sensor objects for PowerMacs thermal control");
  MODULE_LICENSE("GPL");