1/*
2 * smsc47b397.c - Part of lm_sensors, Linux kernel modules
3 * for hardware monitoring
4 *
5 * Supports the SMSC LPC47B397-NC Super-I/O chip.
6 *
7 * Author/Maintainer: Mark M. Hoffman <mhoffman@lightlink.com>
8 * Copyright (C) 2004 Utilitek Systems, Inc.
9 *
10 * derived in part from smsc47m1.c:
11 * Copyright (C) 2002 Mark D. Studebaker <mdsxyz123@yahoo.com>
12 * Copyright (C) 2004 Jean Delvare <jdelvare@suse.de>
13 *
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
18 *
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22 * GNU General Public License for more details.
23 *
24 * You should have received a copy of the GNU General Public License
25 * along with this program; if not, write to the Free Software
26 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
27 */
28
29#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
30
31#include <linux/module.h>
32#include <linux/slab.h>
33#include <linux/ioport.h>
34#include <linux/jiffies.h>
35#include <linux/platform_device.h>
36#include <linux/hwmon.h>
37#include <linux/hwmon-sysfs.h>
38#include <linux/err.h>
39#include <linux/init.h>
40#include <linux/mutex.h>
41#include <linux/acpi.h>
42#include <linux/io.h>
43
44static unsigned short force_id;
45module_param(force_id, ushort, 0);
46MODULE_PARM_DESC(force_id, "Override the detected device ID");
47
48static struct platform_device *pdev;
49
50#define DRVNAME "smsc47b397"
51
52/* Super-I/0 registers and commands */
53
54#define	REG	0x2e	/* The register to read/write */
55#define	VAL	0x2f	/* The value to read/write */
56
57static inline void superio_outb(int reg, int val)
58{
59	outb(reg, REG);
60	outb(val, VAL);
61}
62
63static inline int superio_inb(int reg)
64{
65	outb(reg, REG);
66	return inb(VAL);
67}
68
69/* select superio logical device */
70static inline void superio_select(int ld)
71{
72	superio_outb(0x07, ld);
73}
74
75static inline void superio_enter(void)
76{
77	outb(0x55, REG);
78}
79
80static inline void superio_exit(void)
81{
82	outb(0xAA, REG);
83}
84
85#define SUPERIO_REG_DEVID	0x20
86#define SUPERIO_REG_DEVREV	0x21
87#define SUPERIO_REG_BASE_MSB	0x60
88#define SUPERIO_REG_BASE_LSB	0x61
89#define SUPERIO_REG_LD8		0x08
90
91#define SMSC_EXTENT		0x02
92
93/* 0 <= nr <= 3 */
94static u8 smsc47b397_reg_temp[] = {0x25, 0x26, 0x27, 0x80};
95#define SMSC47B397_REG_TEMP(nr)	(smsc47b397_reg_temp[(nr)])
96
97/* 0 <= nr <= 3 */
98#define SMSC47B397_REG_FAN_LSB(nr) (0x28 + 2 * (nr))
99#define SMSC47B397_REG_FAN_MSB(nr) (0x29 + 2 * (nr))
100
101struct smsc47b397_data {
102	unsigned short addr;
103	struct mutex lock;
104
105	struct mutex update_lock;
106	unsigned long last_updated; /* in jiffies */
107	int valid;
108
109	/* register values */
110	u16 fan[4];
111	u8 temp[4];
112};
113
114static int smsc47b397_read_value(struct smsc47b397_data *data, u8 reg)
115{
116	int res;
117
118	mutex_lock(&data->lock);
119	outb(reg, data->addr);
120	res = inb_p(data->addr + 1);
121	mutex_unlock(&data->lock);
122	return res;
123}
124
125static struct smsc47b397_data *smsc47b397_update_device(struct device *dev)
126{
127	struct smsc47b397_data *data = dev_get_drvdata(dev);
128	int i;
129
130	mutex_lock(&data->update_lock);
131
132	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
133		dev_dbg(dev, "starting device update...\n");
134
135		/* 4 temperature inputs, 4 fan inputs */
136		for (i = 0; i < 4; i++) {
137			data->temp[i] = smsc47b397_read_value(data,
138					SMSC47B397_REG_TEMP(i));
139
140			/* must read LSB first */
141			data->fan[i]  = smsc47b397_read_value(data,
142					SMSC47B397_REG_FAN_LSB(i));
143			data->fan[i] |= smsc47b397_read_value(data,
144					SMSC47B397_REG_FAN_MSB(i)) << 8;
145		}
146
147		data->last_updated = jiffies;
148		data->valid = 1;
149
150		dev_dbg(dev, "... device update complete\n");
151	}
152
153	mutex_unlock(&data->update_lock);
154
155	return data;
156}
157
158/*
159 * TEMP: 0.001C/bit (-128C to +127C)
160 * REG: 1C/bit, two's complement
161 */
162static int temp_from_reg(u8 reg)
163{
164	return (s8)reg * 1000;
165}
166
167static ssize_t show_temp(struct device *dev, struct device_attribute
168			 *devattr, char *buf)
169{
170	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
171	struct smsc47b397_data *data = smsc47b397_update_device(dev);
172	return sprintf(buf, "%d\n", temp_from_reg(data->temp[attr->index]));
173}
174
175static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
176static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
177static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
178static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);
179
180/*
181 * FAN: 1 RPM/bit
182 * REG: count of 90kHz pulses / revolution
183 */
184static int fan_from_reg(u16 reg)
185{
186	if (reg == 0 || reg == 0xffff)
187		return 0;
188	return 90000 * 60 / reg;
189}
190
191static ssize_t show_fan(struct device *dev, struct device_attribute
192			*devattr, char *buf)
193{
194	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
195	struct smsc47b397_data *data = smsc47b397_update_device(dev);
196	return sprintf(buf, "%d\n", fan_from_reg(data->fan[attr->index]));
197}
198static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, show_fan, NULL, 0);
199static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, show_fan, NULL, 1);
200static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, show_fan, NULL, 2);
201static SENSOR_DEVICE_ATTR(fan4_input, S_IRUGO, show_fan, NULL, 3);
202
203static struct attribute *smsc47b397_attrs[] = {
204	&sensor_dev_attr_temp1_input.dev_attr.attr,
205	&sensor_dev_attr_temp2_input.dev_attr.attr,
206	&sensor_dev_attr_temp3_input.dev_attr.attr,
207	&sensor_dev_attr_temp4_input.dev_attr.attr,
208	&sensor_dev_attr_fan1_input.dev_attr.attr,
209	&sensor_dev_attr_fan2_input.dev_attr.attr,
210	&sensor_dev_attr_fan3_input.dev_attr.attr,
211	&sensor_dev_attr_fan4_input.dev_attr.attr,
212
213	NULL
214};
215
216ATTRIBUTE_GROUPS(smsc47b397);
217
218static int smsc47b397_probe(struct platform_device *pdev);
219
220static struct platform_driver smsc47b397_driver = {
221	.driver = {
222		.name	= DRVNAME,
223	},
224	.probe		= smsc47b397_probe,
225};
226
227static int smsc47b397_probe(struct platform_device *pdev)
228{
229	struct device *dev = &pdev->dev;
230	struct smsc47b397_data *data;
231	struct device *hwmon_dev;
232	struct resource *res;
233
234	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
235	if (!devm_request_region(dev, res->start, SMSC_EXTENT,
236				 smsc47b397_driver.driver.name)) {
237		dev_err(dev, "Region 0x%lx-0x%lx already in use!\n",
238			(unsigned long)res->start,
239			(unsigned long)res->start + SMSC_EXTENT - 1);
240		return -EBUSY;
241	}
242
243	data = devm_kzalloc(dev, sizeof(struct smsc47b397_data), GFP_KERNEL);
244	if (!data)
245		return -ENOMEM;
246
247	data->addr = res->start;
248	mutex_init(&data->lock);
249	mutex_init(&data->update_lock);
250
251	hwmon_dev = devm_hwmon_device_register_with_groups(dev, "smsc47b397",
252							   data,
253							   smsc47b397_groups);
254	return PTR_ERR_OR_ZERO(hwmon_dev);
255}
256
257static int __init smsc47b397_device_add(unsigned short address)
258{
259	struct resource res = {
260		.start	= address,
261		.end	= address + SMSC_EXTENT - 1,
262		.name	= DRVNAME,
263		.flags	= IORESOURCE_IO,
264	};
265	int err;
266
267	err = acpi_check_resource_conflict(&res);
268	if (err)
269		goto exit;
270
271	pdev = platform_device_alloc(DRVNAME, address);
272	if (!pdev) {
273		err = -ENOMEM;
274		pr_err("Device allocation failed\n");
275		goto exit;
276	}
277
278	err = platform_device_add_resources(pdev, &res, 1);
279	if (err) {
280		pr_err("Device resource addition failed (%d)\n", err);
281		goto exit_device_put;
282	}
283
284	err = platform_device_add(pdev);
285	if (err) {
286		pr_err("Device addition failed (%d)\n", err);
287		goto exit_device_put;
288	}
289
290	return 0;
291
292exit_device_put:
293	platform_device_put(pdev);
294exit:
295	return err;
296}
297
298static int __init smsc47b397_find(void)
299{
300	u8 id, rev;
301	char *name;
302	unsigned short addr;
303
304	superio_enter();
305	id = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID);
306
307	switch (id) {
308	case 0x81:
309		name = "SCH5307-NS";
310		break;
311	case 0x6f:
312		name = "LPC47B397-NC";
313		break;
314	case 0x85:
315	case 0x8c:
316		name = "SCH5317";
317		break;
318	default:
319		superio_exit();
320		return -ENODEV;
321	}
322
323	rev = superio_inb(SUPERIO_REG_DEVREV);
324
325	superio_select(SUPERIO_REG_LD8);
326	addr = (superio_inb(SUPERIO_REG_BASE_MSB) << 8)
327		 |  superio_inb(SUPERIO_REG_BASE_LSB);
328
329	pr_info("found SMSC %s (base address 0x%04x, revision %u)\n",
330		name, addr, rev);
331
332	superio_exit();
333	return addr;
334}
335
336static int __init smsc47b397_init(void)
337{
338	unsigned short address;
339	int ret;
340
341	ret = smsc47b397_find();
342	if (ret < 0)
343		return ret;
344	address = ret;
345
346	ret = platform_driver_register(&smsc47b397_driver);
347	if (ret)
348		goto exit;
349
350	/* Sets global pdev as a side effect */
351	ret = smsc47b397_device_add(address);
352	if (ret)
353		goto exit_driver;
354
355	return 0;
356
357exit_driver:
358	platform_driver_unregister(&smsc47b397_driver);
359exit:
360	return ret;
361}
362
363static void __exit smsc47b397_exit(void)
364{
365	platform_device_unregister(pdev);
366	platform_driver_unregister(&smsc47b397_driver);
367}
368
369MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
370MODULE_DESCRIPTION("SMSC LPC47B397 driver");
371MODULE_LICENSE("GPL");
372
373module_init(smsc47b397_init);
374module_exit(smsc47b397_exit);
375