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(value: reg, REG);
47 outb(value: val, VAL);
48}
49
50static inline int superio_inb(int reg)
51{
52 outb(value: reg, REG);
53 return inb(VAL);
54}
55
56/* select superio logical device */
57static inline void superio_select(int ld)
58{
59 superio_outb(reg: 0x07, val: ld);
60}
61
62static inline int superio_enter(void)
63{
64 if (!request_muxed_region(REG, 2, DRVNAME))
65 return -EBUSY;
66
67 outb(value: 0x55, REG);
68 return 0;
69}
70
71static inline void superio_exit(void)
72{
73 outb(value: 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(value: reg, port: data->addr);
112 res = inb_p(port: data->addr + 1);
113 mutex_unlock(lock: &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(lock: &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, fmt: "%d\n", temp_from_reg(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, fmt: "%d\n", fan_from_reg(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, size: 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, name: "smsc47b397",
244 drvdata: data,
245 groups: smsc47b397_groups);
246 return PTR_ERR_OR_ZERO(ptr: 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: &res);
260 if (err)
261 goto exit;
262
263 pdev = platform_device_alloc(DRVNAME, id: 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: &res, num: 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

source code of linux/drivers/hwmon/smsc47b397.c