[mirror_ubuntu-hirsute-kernel.git] / drivers / macintosh / windfarm_lm87_sensor.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Windfarm PowerMac thermal control. LM87 sensor
 *
 * Copyright 2012 Benjamin Herrenschmidt, IBM Corp.
 */

#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 <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_lm87_sensor {
	struct i2c_client	*i2c;
	struct wf_sensor	sens;
};
#define wf_to_lm87(c) container_of(c, struct wf_lm87_sensor, sens)


static int wf_lm87_read_reg(struct i2c_client *chip, int reg)
{
	int rc, tries = 0;
	u8 buf;

	for (;;) {
		/* Set address */
		buf = (u8)reg;
		rc = i2c_master_send(chip, &buf, 1);
		if (rc <= 0)
			goto error;
		rc = i2c_master_recv(chip, &buf, 1);
		if (rc <= 0)
			goto error;
		return (int)buf;
	error:
		DBG("wf_lm87: Error reading LM87, retrying...\n");
		if (++tries > 10) {
			printk(KERN_ERR "wf_lm87: Error reading LM87 !\n");
			return -EIO;
		}
		msleep(10);
	}
}

static int wf_lm87_get(struct wf_sensor *sr, s32 *value)
{
	struct wf_lm87_sensor *lm = sr->priv;
	s32 temp;

	if (lm->i2c == NULL)
		return -ENODEV;

#define LM87_INT_TEMP		0x27

	/* Read temperature register */
	temp = wf_lm87_read_reg(lm->i2c, LM87_INT_TEMP);
	if (temp < 0)
		return temp;
	*value = temp << 16;

	return 0;
}

static void wf_lm87_release(struct wf_sensor *sr)
{
	struct wf_lm87_sensor *lm = wf_to_lm87(sr);

	kfree(lm);
}

static const struct wf_sensor_ops wf_lm87_ops = {
	.get_value	= wf_lm87_get,
	.release	= wf_lm87_release,
	.owner		= THIS_MODULE,
};

static int wf_lm87_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{	
	struct wf_lm87_sensor *lm;
	const char *name = NULL, *loc;
	struct device_node *np = NULL;
	int rc;

	/*
	 * The lm87 contains a whole pile of sensors, additionally,
	 * the Xserve G5 has several lm87's. However, for now we only
	 * care about the internal temperature sensor
	 */
	for_each_child_of_node(client->dev.of_node, np) {
		if (!of_node_name_eq(np, "int-temp"))
			continue;
		loc = of_get_property(np, "location", NULL);
		if (!loc)
			continue;
		if (strstr(loc, "DIMM"))
			name = "dimms-temp";
		else if (strstr(loc, "Processors"))
			name = "between-cpus-temp";
		if (name) {
			of_node_put(np);
			break;
		}
	}
	if (!name) {
		pr_warn("wf_lm87: Unsupported sensor %pOF\n",
			client->dev.of_node);
		return -ENODEV;
	}

	lm = kzalloc(sizeof(struct wf_lm87_sensor), GFP_KERNEL);
	if (lm == NULL)
		return -ENODEV;

	lm->i2c = client;
	lm->sens.name = name;
	lm->sens.ops = &wf_lm87_ops;
	lm->sens.priv = lm;
	i2c_set_clientdata(client, lm);

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

static int wf_lm87_remove(struct i2c_client *client)
{
	struct wf_lm87_sensor *lm = i2c_get_clientdata(client);

	DBG("wf_lm87: i2c detatch called for %s\n", lm->sens.name);

	/* Mark client detached */
	lm->i2c = NULL;

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

	return 0;
}

static const struct i2c_device_id wf_lm87_id[] = {
	{ "MAC,lm87cimt", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, wf_lm87_id);

static const struct of_device_id wf_lm87_of_id[] = {
	{ .compatible = "lm87cimt", },
	{ }
};
MODULE_DEVICE_TABLE(of, wf_lm87_of_id);

static struct i2c_driver wf_lm87_driver = {
	.driver = {
		.name	= "wf_lm87",
		.of_match_table = wf_lm87_of_id,
	},
	.probe		= wf_lm87_probe,
	.remove		= wf_lm87_remove,
	.id_table	= wf_lm87_id,
};

static int __init wf_lm87_sensor_init(void)
{
	/* We only support this on the Xserve */
	if (!of_machine_is_compatible("RackMac3,1"))
		return -ENODEV;

	return i2c_add_driver(&wf_lm87_driver);
}

static void __exit wf_lm87_sensor_exit(void)
{
	i2c_del_driver(&wf_lm87_driver);
}


module_init(wf_lm87_sensor_init);
module_exit(wf_lm87_sensor_exit);

MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
MODULE_DESCRIPTION("LM87 sensor objects for PowerMacs thermal control");
MODULE_LICENSE("GPL");
Commit	Line	Data
2c162f9b	1	// SPDX-License-Identifier: GPL-2.0-only
08fe5bc7 BH	2	/*
	3	* Windfarm PowerMac thermal control. LM87 sensor
	4	*
	5	* Copyright 2012 Benjamin Herrenschmidt, IBM Corp.
08fe5bc7 BH	6	*/
	7
	8	#include <linux/types.h>
	9	#include <linux/errno.h>
	10	#include <linux/kernel.h>
	11	#include <linux/delay.h>
	12	#include <linux/slab.h>
	13	#include <linux/init.h>
	14	#include <linux/wait.h>
	15	#include <linux/i2c.h>
	16	#include <asm/prom.h>
	17	#include <asm/machdep.h>
	18	#include <asm/io.h>
	19	#include <asm/sections.h>
	20	#include <asm/pmac_low_i2c.h>
	21
	22	#include "windfarm.h"
	23
	24	#define VERSION "1.0"
	25
	26	#undef DEBUG
	27
	28	#ifdef DEBUG
	29	#define DBG(args...) printk(args)
	30	#else
	31	#define DBG(args...) do { } while(0)
	32	#endif
	33
	34	struct wf_lm87_sensor {
	35	struct i2c_client *i2c;
	36	struct wf_sensor sens;
	37	};
	38	#define wf_to_lm87(c) container_of(c, struct wf_lm87_sensor, sens)
	39
	40
	41	static int wf_lm87_read_reg(struct i2c_client *chip, int reg)
	42	{
	43	int rc, tries = 0;
	44	u8 buf;
	45
	46	for (;;) {
	47	/* Set address */
	48	buf = (u8)reg;
	49	rc = i2c_master_send(chip, &buf, 1);
	50	if (rc <= 0)
	51	goto error;
	52	rc = i2c_master_recv(chip, &buf, 1);
	53	if (rc <= 0)
	54	goto error;
	55	return (int)buf;
	56	error:
	57	DBG("wf_lm87: Error reading LM87, retrying...\n");
	58	if (++tries > 10) {
	59	printk(KERN_ERR "wf_lm87: Error reading LM87 !\n");
	60	return -EIO;
	61	}
	62	msleep(10);
	63	}
	64	}
	65
	66	static int wf_lm87_get(struct wf_sensor sr, s32 value)
	67	{
	68	struct wf_lm87_sensor *lm = sr->priv;
	69	s32 temp;
70
71	if (lm->i2c == NULL)
72	return -ENODEV;
73
74	#define LM87_INT_TEMP 0x27
75
76	/* Read temperature register */
77	temp = wf_lm87_read_reg(lm->i2c, LM87_INT_TEMP);
78	if (temp < 0)
79	return temp;
80	*value = temp << 16;
81
82	return 0;
83	}
84
85	static void wf_lm87_release(struct wf_sensor *sr)
86	{
87	struct wf_lm87_sensor *lm = wf_to_lm87(sr);
88
89	kfree(lm);
90	}
91
de854e54	92	static const struct wf_sensor_ops wf_lm87_ops = {
08fe5bc7 BH	93	.get_value = wf_lm87_get,
	94	.release = wf_lm87_release,
	95	.owner = THIS_MODULE,
	96	};
	97
	98	static int wf_lm87_probe(struct i2c_client *client,
	99	const struct i2c_device_id *id)
	100	{
	101	struct wf_lm87_sensor *lm;
	102	const char name = NULL, loc;
	103	struct device_node *np = NULL;
	104	int rc;
	105
	106	/*
	107	* The lm87 contains a whole pile of sensors, additionally,
	108	* the Xserve G5 has several lm87's. However, for now we only
	109	* care about the internal temperature sensor
	110	*/
f1e0addc RH	111	for_each_child_of_node(client->dev.of_node, np) {
f1e0addc RH	112	if (!of_node_name_eq(np, "int-temp"))
08fe5bc7 BH	113	continue;
	114	loc = of_get_property(np, "location", NULL);
	115	if (!loc)
	116	continue;
	117	if (strstr(loc, "DIMM"))
	118	name = "dimms-temp";
	119	else if (strstr(loc, "Processors"))
	120	name = "between-cpus-temp";
	121	if (name) {
	122	of_node_put(np);
	123	break;
	124	}
	125	}
	126	if (!name) {
2ee9a0db KW	127	pr_warn("wf_lm87: Unsupported sensor %pOF\n",
2ee9a0db KW	128	client->dev.of_node);
08fe5bc7 BH	129	return -ENODEV;
	130	}
	131
	132	lm = kzalloc(sizeof(struct wf_lm87_sensor), GFP_KERNEL);
	133	if (lm == NULL)
	134	return -ENODEV;
	135
	136	lm->i2c = client;
	137	lm->sens.name = name;
	138	lm->sens.ops = &wf_lm87_ops;
	139	lm->sens.priv = lm;
	140	i2c_set_clientdata(client, lm);
	141
	142	rc = wf_register_sensor(&lm->sens);
	143	if (rc)
	144	kfree(lm);
	145	return rc;
	146	}
	147
	148	static int wf_lm87_remove(struct i2c_client *client)
	149	{
	150	struct wf_lm87_sensor *lm = i2c_get_clientdata(client);
	151
	152	DBG("wf_lm87: i2c detatch called for %s\n", lm->sens.name);
	153
	154	/* Mark client detached */
	155	lm->i2c = NULL;
	156
	157	/* release sensor */
	158	wf_unregister_sensor(&lm->sens);
	159
	160	return 0;
	161	}
	162
	163	static const struct i2c_device_id wf_lm87_id[] = {
	164	{ "MAC,lm87cimt", 0 },
	165	{ }
	166	};
	167	MODULE_DEVICE_TABLE(i2c, wf_lm87_id);
	168
bcf3588d WS	169	static const struct of_device_id wf_lm87_of_id[] = {
	170	{ .compatible = "lm87cimt", },
	171	{ }
	172	};
	173	MODULE_DEVICE_TABLE(of, wf_lm87_of_id);
	174
08fe5bc7 BH	175	static struct i2c_driver wf_lm87_driver = {
	176	.driver = {
	177	.name = "wf_lm87",
bcf3588d	178	.of_match_table = wf_lm87_of_id,
08fe5bc7 BH	179	},
	180	.probe = wf_lm87_probe,
	181	.remove = wf_lm87_remove,
	182	.id_table = wf_lm87_id,
	183	};
	184
	185	static int __init wf_lm87_sensor_init(void)
	186	{
	187	/* We only support this on the Xserve */
	188	if (!of_machine_is_compatible("RackMac3,1"))
	189	return -ENODEV;
	190
	191	return i2c_add_driver(&wf_lm87_driver);
	192	}
	193
	194	static void __exit wf_lm87_sensor_exit(void)
	195	{
	196	i2c_del_driver(&wf_lm87_driver);
	197	}
	198
	199
	200	module_init(wf_lm87_sensor_init);
	201	module_exit(wf_lm87_sensor_exit);
	202
	203	MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
	204	MODULE_DESCRIPTION("LM87 sensor objects for PowerMacs thermal control");
	205	MODULE_LICENSE("GPL");
	206