1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * smsc47b397.c - Part of lm_sensors, Linux kernel modules
4 * for hardware monitoring
5 *
6 * Supports the SMSC LPC47B397-NC Super-I/O chip.
7 *
8 * Author/Maintainer: Mark M. Hoffman <mhoffman@lightlink.com>
9 * Copyright (C) 2004 Utilitek Systems, Inc.
10 *
11 * derived in part from smsc47m1.c:
12 * Copyright (C) 2002 Mark D. Studebaker <mdsxyz123@yahoo.com>
13 * Copyright (C) 2004 Jean Delvare <jdelvare@suse.de>
14 */
15
16#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
17
18#include <linux/module.h>
19#include <linux/slab.h>
20#include <linux/ioport.h>
21#include <linux/jiffies.h>
22#include <linux/platform_device.h>
23#include <linux/hwmon.h>
24#include <linux/hwmon-sysfs.h>
25#include <linux/err.h>
26#include <linux/init.h>
27#include <linux/mutex.h>
28#include <linux/acpi.h>
29#include <linux/io.h>
30
31static unsigned short force_id;
32module_param(force_id, ushort, 0);
33MODULE_PARM_DESC(force_id, "Override the detected device ID");
34
35static struct platform_device *pdev;
36
37#define DRVNAME "smsc47b397"
38
39/* Super-I/0 registers and commands */
40
41#define	REG	0x2e	/* The register to read/write */
42#define	VAL	0x2f	/* The value to read/write */
43
44static inline void superio_outb(int reg, int val)
45{
46	outb(reg, REG);
47	outb(val, VAL);
48}
49
50static inline int superio_inb(int reg)
51{
52	outb(reg, REG);
53	return inb(VAL);
54}
55
56/* select superio logical device */
57static inline void superio_select(int ld)
58{
59	superio_outb(0x07, ld);
60}
61
62static inline int superio_enter(void)
63{
64	if (!request_muxed_region(REG, 2, DRVNAME))
65		return -EBUSY;
66
67	outb(0x55, REG);
68	return 0;
69}
70
71static inline void superio_exit(void)
72{
73	outb(0xAA, REG);
74	release_region(REG, 2);
75}
76
77#define SUPERIO_REG_DEVID	0x20
78#define SUPERIO_REG_DEVREV	0x21
79#define SUPERIO_REG_BASE_MSB	0x60
80#define SUPERIO_REG_BASE_LSB	0x61
81#define SUPERIO_REG_LD8		0x08
82
83#define SMSC_EXTENT		0x02
84
85/* 0 <= nr <= 3 */
86static u8 smsc47b397_reg_temp[] = {0x25, 0x26, 0x27, 0x80};
87#define SMSC47B397_REG_TEMP(nr)	(smsc47b397_reg_temp[(nr)])
88
89/* 0 <= nr <= 3 */
90#define SMSC47B397_REG_FAN_LSB(nr) (0x28 + 2 * (nr))
91#define SMSC47B397_REG_FAN_MSB(nr) (0x29 + 2 * (nr))
92
93struct smsc47b397_data {
94	unsigned short addr;
95	struct mutex lock;
96
97	struct mutex update_lock;
98	unsigned long last_updated; /* in jiffies */
99	bool valid;
100
101	/* register values */
102	u16 fan[4];
103	u8 temp[4];
104};
105
106static int smsc47b397_read_value(struct smsc47b397_data *data, u8 reg)
107{
108	int res;
109
110	mutex_lock(&data->lock);
111	outb(reg, data->addr);
112	res = inb_p(data->addr + 1);
113	mutex_unlock(&data->lock);
114	return res;
115}
116
117static struct smsc47b397_data *smsc47b397_update_device(struct device *dev)
118{
119	struct smsc47b397_data *data = dev_get_drvdata(dev);
120	int i;
121
122	mutex_lock(&data->update_lock);
123
124	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
125		dev_dbg(dev, "starting device update...\n");
126
127		/* 4 temperature inputs, 4 fan inputs */
128		for (i = 0; i < 4; i++) {
129			data->temp[i] = smsc47b397_read_value(data,
130					SMSC47B397_REG_TEMP(i));
131
132			/* must read LSB first */
133			data->fan[i]  = smsc47b397_read_value(data,
134					SMSC47B397_REG_FAN_LSB(i));
135			data->fan[i] |= smsc47b397_read_value(data,
136					SMSC47B397_REG_FAN_MSB(i)) << 8;
137		}
138
139		data->last_updated = jiffies;
140		data->valid = true;
141
142		dev_dbg(dev, "... device update complete\n");
143	}
144
145	mutex_unlock(&data->update_lock);
146
147	return data;
148}
149
150/*
151 * TEMP: 0.001C/bit (-128C to +127C)
152 * REG: 1C/bit, two's complement
153 */
154static int temp_from_reg(u8 reg)
155{
156	return (s8)reg * 1000;
157}
158
159static ssize_t temp_show(struct device *dev, struct device_attribute *devattr,
160			 char *buf)
161{
162	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
163	struct smsc47b397_data *data = smsc47b397_update_device(dev);
164	return sprintf(buf, "%d\n", temp_from_reg(data->temp[attr->index]));
165}
166
167static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, 0);
168static SENSOR_DEVICE_ATTR_RO(temp2_input, temp, 1);
169static SENSOR_DEVICE_ATTR_RO(temp3_input, temp, 2);
170static SENSOR_DEVICE_ATTR_RO(temp4_input, temp, 3);
171
172/*
173 * FAN: 1 RPM/bit
174 * REG: count of 90kHz pulses / revolution
175 */
176static int fan_from_reg(u16 reg)
177{
178	if (reg == 0 || reg == 0xffff)
179		return 0;
180	return 90000 * 60 / reg;
181}
182
183static ssize_t fan_show(struct device *dev, struct device_attribute *devattr,
184			char *buf)
185{
186	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
187	struct smsc47b397_data *data = smsc47b397_update_device(dev);
188	return sprintf(buf, "%d\n", fan_from_reg(data->fan[attr->index]));
189}
190static SENSOR_DEVICE_ATTR_RO(fan1_input, fan, 0);
191static SENSOR_DEVICE_ATTR_RO(fan2_input, fan, 1);
192static SENSOR_DEVICE_ATTR_RO(fan3_input, fan, 2);
193static SENSOR_DEVICE_ATTR_RO(fan4_input, fan, 3);
194
195static struct attribute *smsc47b397_attrs[] = {
196	&sensor_dev_attr_temp1_input.dev_attr.attr,
197	&sensor_dev_attr_temp2_input.dev_attr.attr,
198	&sensor_dev_attr_temp3_input.dev_attr.attr,
199	&sensor_dev_attr_temp4_input.dev_attr.attr,
200	&sensor_dev_attr_fan1_input.dev_attr.attr,
201	&sensor_dev_attr_fan2_input.dev_attr.attr,
202	&sensor_dev_attr_fan3_input.dev_attr.attr,
203	&sensor_dev_attr_fan4_input.dev_attr.attr,
204
205	NULL
206};
207
208ATTRIBUTE_GROUPS(smsc47b397);
209
210static int smsc47b397_probe(struct platform_device *pdev);
211
212static struct platform_driver smsc47b397_driver = {
213	.driver = {
214		.name	= DRVNAME,
215	},
216	.probe		= smsc47b397_probe,
217};
218
219static int smsc47b397_probe(struct platform_device *pdev)
220{
221	struct device *dev = &pdev->dev;
222	struct smsc47b397_data *data;
223	struct device *hwmon_dev;
224	struct resource *res;
225
226	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
227	if (!devm_request_region(dev, res->start, SMSC_EXTENT,
228				 smsc47b397_driver.driver.name)) {
229		dev_err(dev, "Region 0x%lx-0x%lx already in use!\n",
230			(unsigned long)res->start,
231			(unsigned long)res->start + SMSC_EXTENT - 1);
232		return -EBUSY;
233	}
234
235	data = devm_kzalloc(dev, sizeof(struct smsc47b397_data), GFP_KERNEL);
236	if (!data)
237		return -ENOMEM;
238
239	data->addr = res->start;
240	mutex_init(&data->lock);
241	mutex_init(&data->update_lock);
242
243	hwmon_dev = devm_hwmon_device_register_with_groups(dev, "smsc47b397",
244							   data,
245							   smsc47b397_groups);
246	return PTR_ERR_OR_ZERO(hwmon_dev);
247}
248
249static int __init smsc47b397_device_add(unsigned short address)
250{
251	struct resource res = {
252		.start	= address,
253		.end	= address + SMSC_EXTENT - 1,
254		.name	= DRVNAME,
255		.flags	= IORESOURCE_IO,
256	};
257	int err;
258
259	err = acpi_check_resource_conflict(&res);
260	if (err)
261		goto exit;
262
263	pdev = platform_device_alloc(DRVNAME, address);
264	if (!pdev) {
265		err = -ENOMEM;
266		pr_err("Device allocation failed\n");
267		goto exit;
268	}
269
270	err = platform_device_add_resources(pdev, &res, 1);
271	if (err) {
272		pr_err("Device resource addition failed (%d)\n", err);
273		goto exit_device_put;
274	}
275
276	err = platform_device_add(pdev);
277	if (err) {
278		pr_err("Device addition failed (%d)\n", err);
279		goto exit_device_put;
280	}
281
282	return 0;
283
284exit_device_put:
285	platform_device_put(pdev);
286exit:
287	return err;
288}
289
290static int __init smsc47b397_find(void)
291{
292	u8 id, rev;
293	char *name;
294	unsigned short addr;
295	int err;
296
297	err = superio_enter();
298	if (err)
299		return err;
300
301	id = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID);
302
303	switch (id) {
304	case 0x81:
305		name = "SCH5307-NS";
306		break;
307	case 0x6f:
308		name = "LPC47B397-NC";
309		break;
310	case 0x85:
311	case 0x8c:
312		name = "SCH5317";
313		break;
314	default:
315		superio_exit();
316		return -ENODEV;
317	}
318
319	rev = superio_inb(SUPERIO_REG_DEVREV);
320
321	superio_select(SUPERIO_REG_LD8);
322	addr = (superio_inb(SUPERIO_REG_BASE_MSB) << 8)
323		 |  superio_inb(SUPERIO_REG_BASE_LSB);
324
325	pr_info("found SMSC %s (base address 0x%04x, revision %u)\n",
326		name, addr, rev);
327
328	superio_exit();
329	return addr;
330}
331
332static int __init smsc47b397_init(void)
333{
334	unsigned short address;
335	int ret;
336
337	ret = smsc47b397_find();
338	if (ret < 0)
339		return ret;
340	address = ret;
341
342	ret = platform_driver_register(&smsc47b397_driver);
343	if (ret)
344		goto exit;
345
346	/* Sets global pdev as a side effect */
347	ret = smsc47b397_device_add(address);
348	if (ret)
349		goto exit_driver;
350
351	return 0;
352
353exit_driver:
354	platform_driver_unregister(&smsc47b397_driver);
355exit:
356	return ret;
357}
358
359static void __exit smsc47b397_exit(void)
360{
361	platform_device_unregister(pdev);
362	platform_driver_unregister(&smsc47b397_driver);
363}
364
365MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
366MODULE_DESCRIPTION("SMSC LPC47B397 driver");
367MODULE_LICENSE("GPL");
368
369module_init(smsc47b397_init);
370module_exit(smsc47b397_exit);
371