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authorHans de Goede <hdegoede@redhat.com>2011-07-25 15:46:09 -0400
committerJean Delvare <khali@endymion.delvare>2011-07-25 15:46:09 -0400
commit28ff2f7a742daba86ccd7021be7b27a4673b2797 (patch)
tree1c6d11e31c793adbdef731a2640842ea06566539 /drivers/hwmon/sch56xx-common.c
parentb6844e8f64920cdee620157252169ba63afb0c89 (diff)
hwmon: (sch5627) Factor out some code shared with sch5636 driver
This patch adds a new sch56xx-common.ko which contains code which will also be used in the new sch5636 driver. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
Diffstat (limited to 'drivers/hwmon/sch56xx-common.c')
-rw-r--r--drivers/hwmon/sch56xx-common.c336
1 files changed, 336 insertions, 0 deletions
diff --git a/drivers/hwmon/sch56xx-common.c b/drivers/hwmon/sch56xx-common.c
new file mode 100644
index 000000000000..a579313b55df
--- /dev/null
+++ b/drivers/hwmon/sch56xx-common.c
@@ -0,0 +1,336 @@
1/***************************************************************************
2 * Copyright (C) 2010-2011 Hans de Goede <hdegoede@redhat.com> *
3 * *
4 * This program is free software; you can redistribute it and/or modify *
5 * it under the terms of the GNU General Public License as published by *
6 * the Free Software Foundation; either version 2 of the License, or *
7 * (at your option) any later version. *
8 * *
9 * This program is distributed in the hope that it will be useful, *
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of *
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
12 * GNU General Public License for more details. *
13 * *
14 * You should have received a copy of the GNU General Public License *
15 * along with this program; if not, write to the *
16 * Free Software Foundation, Inc., *
17 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
18 ***************************************************************************/
19
20#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
21
22#include <linux/module.h>
23#include <linux/init.h>
24#include <linux/platform_device.h>
25#include <linux/err.h>
26#include <linux/io.h>
27#include <linux/acpi.h>
28#include <linux/delay.h>
29#include "sch56xx-common.h"
30
31#define SIO_SCH56XX_LD_EM 0x0C /* Embedded uController Logical Dev */
32#define SIO_UNLOCK_KEY 0x55 /* Key to enable Super-I/O */
33#define SIO_LOCK_KEY 0xAA /* Key to disable Super-I/O */
34
35#define SIO_REG_LDSEL 0x07 /* Logical device select */
36#define SIO_REG_DEVID 0x20 /* Device ID */
37#define SIO_REG_ENABLE 0x30 /* Logical device enable */
38#define SIO_REG_ADDR 0x66 /* Logical device address (2 bytes) */
39
40#define SIO_SCH5627_ID 0xC6 /* Chipset ID */
41
42#define REGION_LENGTH 9
43
44#define SCH56XX_CMD_READ 0x02
45#define SCH56XX_CMD_WRITE 0x03
46
47static struct platform_device *sch56xx_pdev;
48
49/* Super I/O functions */
50static inline int superio_inb(int base, int reg)
51{
52 outb(reg, base);
53 return inb(base + 1);
54}
55
56static inline int superio_enter(int base)
57{
58 /* Don't step on other drivers' I/O space by accident */
59 if (!request_muxed_region(base, 2, "sch56xx")) {
60 pr_err("I/O address 0x%04x already in use\n", base);
61 return -EBUSY;
62 }
63
64 outb(SIO_UNLOCK_KEY, base);
65
66 return 0;
67}
68
69static inline void superio_select(int base, int ld)
70{
71 outb(SIO_REG_LDSEL, base);
72 outb(ld, base + 1);
73}
74
75static inline void superio_exit(int base)
76{
77 outb(SIO_LOCK_KEY, base);
78 release_region(base, 2);
79}
80
81static int sch56xx_send_cmd(u16 addr, u8 cmd, u16 reg, u8 v)
82{
83 u8 val;
84 int i;
85 /*
86 * According to SMSC for the commands we use the maximum time for
87 * the EM to respond is 15 ms, but testing shows in practice it
88 * responds within 15-32 reads, so we first busy poll, and if
89 * that fails sleep a bit and try again until we are way past
90 * the 15 ms maximum response time.
91 */
92 const int max_busy_polls = 64;
93 const int max_lazy_polls = 32;
94
95 /* (Optional) Write-Clear the EC to Host Mailbox Register */
96 val = inb(addr + 1);
97 outb(val, addr + 1);
98
99 /* Set Mailbox Address Pointer to first location in Region 1 */
100 outb(0x00, addr + 2);
101 outb(0x80, addr + 3);
102
103 /* Write Request Packet Header */
104 outb(cmd, addr + 4); /* VREG Access Type read:0x02 write:0x03 */
105 outb(0x01, addr + 5); /* # of Entries: 1 Byte (8-bit) */
106 outb(0x04, addr + 2); /* Mailbox AP to first data entry loc. */
107
108 /* Write Value field */
109 if (cmd == SCH56XX_CMD_WRITE)
110 outb(v, addr + 4);
111
112 /* Write Address field */
113 outb(reg & 0xff, addr + 6);
114 outb(reg >> 8, addr + 7);
115
116 /* Execute the Random Access Command */
117 outb(0x01, addr); /* Write 01h to the Host-to-EC register */
118
119 /* EM Interface Polling "Algorithm" */
120 for (i = 0; i < max_busy_polls + max_lazy_polls; i++) {
121 if (i >= max_busy_polls)
122 msleep(1);
123 /* Read Interrupt source Register */
124 val = inb(addr + 8);
125 /* Write Clear the interrupt source bits */
126 if (val)
127 outb(val, addr + 8);
128 /* Command Completed ? */
129 if (val & 0x01)
130 break;
131 }
132 if (i == max_busy_polls + max_lazy_polls) {
133 pr_err("Max retries exceeded reading virtual "
134 "register 0x%04hx (%d)\n", reg, 1);
135 return -EIO;
136 }
137
138 /*
139 * According to SMSC we may need to retry this, but sofar I've always
140 * seen this succeed in 1 try.
141 */
142 for (i = 0; i < max_busy_polls; i++) {
143 /* Read EC-to-Host Register */
144 val = inb(addr + 1);
145 /* Command Completed ? */
146 if (val == 0x01)
147 break;
148
149 if (i == 0)
150 pr_warn("EC reports: 0x%02x reading virtual register "
151 "0x%04hx\n", (unsigned int)val, reg);
152 }
153 if (i == max_busy_polls) {
154 pr_err("Max retries exceeded reading virtual "
155 "register 0x%04hx (%d)\n", reg, 2);
156 return -EIO;
157 }
158
159 /*
160 * According to the SMSC app note we should now do:
161 *
162 * Set Mailbox Address Pointer to first location in Region 1 *
163 * outb(0x00, addr + 2);
164 * outb(0x80, addr + 3);
165 *
166 * But if we do that things don't work, so let's not.
167 */
168
169 /* Read Value field */
170 if (cmd == SCH56XX_CMD_READ)
171 return inb(addr + 4);
172
173 return 0;
174}
175
176int sch56xx_read_virtual_reg(u16 addr, u16 reg)
177{
178 return sch56xx_send_cmd(addr, SCH56XX_CMD_READ, reg, 0);
179}
180EXPORT_SYMBOL(sch56xx_read_virtual_reg);
181
182int sch56xx_write_virtual_reg(u16 addr, u16 reg, u8 val)
183{
184 return sch56xx_send_cmd(addr, SCH56XX_CMD_WRITE, reg, val);
185}
186EXPORT_SYMBOL(sch56xx_write_virtual_reg);
187
188int sch56xx_read_virtual_reg16(u16 addr, u16 reg)
189{
190 int lsb, msb;
191
192 /* Read LSB first, this will cause the matching MSB to be latched */
193 lsb = sch56xx_read_virtual_reg(addr, reg);
194 if (lsb < 0)
195 return lsb;
196
197 msb = sch56xx_read_virtual_reg(addr, reg + 1);
198 if (msb < 0)
199 return msb;
200
201 return lsb | (msb << 8);
202}
203EXPORT_SYMBOL(sch56xx_read_virtual_reg16);
204
205int sch56xx_read_virtual_reg12(u16 addr, u16 msb_reg, u16 lsn_reg,
206 int high_nibble)
207{
208 int msb, lsn;
209
210 /* Read MSB first, this will cause the matching LSN to be latched */
211 msb = sch56xx_read_virtual_reg(addr, msb_reg);
212 if (msb < 0)
213 return msb;
214
215 lsn = sch56xx_read_virtual_reg(addr, lsn_reg);
216 if (lsn < 0)
217 return lsn;
218
219 if (high_nibble)
220 return (msb << 4) | (lsn >> 4);
221 else
222 return (msb << 4) | (lsn & 0x0f);
223}
224EXPORT_SYMBOL(sch56xx_read_virtual_reg12);
225
226static int __init sch56xx_find(int sioaddr, unsigned short *address,
227 const char **name)
228{
229 u8 devid;
230 int err;
231
232 err = superio_enter(sioaddr);
233 if (err)
234 return err;
235
236 devid = superio_inb(sioaddr, SIO_REG_DEVID);
237 switch (devid) {
238 case SIO_SCH5627_ID:
239 *name = "sch5627";
240 break;
241 default:
242 pr_debug("Unsupported device id: 0x%02x\n",
243 (unsigned int)devid);
244 err = -ENODEV;
245 goto exit;
246 }
247
248 superio_select(sioaddr, SIO_SCH56XX_LD_EM);
249
250 if (!(superio_inb(sioaddr, SIO_REG_ENABLE) & 0x01)) {
251 pr_warn("Device not activated\n");
252 err = -ENODEV;
253 goto exit;
254 }
255
256 /*
257 * Warning the order of the low / high byte is the other way around
258 * as on most other superio devices!!
259 */
260 *address = superio_inb(sioaddr, SIO_REG_ADDR) |
261 superio_inb(sioaddr, SIO_REG_ADDR + 1) << 8;
262 if (*address == 0) {
263 pr_warn("Base address not set\n");
264 err = -ENODEV;
265 goto exit;
266 }
267
268exit:
269 superio_exit(sioaddr);
270 return err;
271}
272
273static int __init sch56xx_device_add(unsigned short address, const char *name)
274{
275 struct resource res = {
276 .start = address,
277 .end = address + REGION_LENGTH - 1,
278 .flags = IORESOURCE_IO,
279 };
280 int err;
281
282 sch56xx_pdev = platform_device_alloc(name, address);
283 if (!sch56xx_pdev)
284 return -ENOMEM;
285
286 res.name = sch56xx_pdev->name;
287 err = acpi_check_resource_conflict(&res);
288 if (err)
289 goto exit_device_put;
290
291 err = platform_device_add_resources(sch56xx_pdev, &res, 1);
292 if (err) {
293 pr_err("Device resource addition failed\n");
294 goto exit_device_put;
295 }
296
297 err = platform_device_add(sch56xx_pdev);
298 if (err) {
299 pr_err("Device addition failed\n");
300 goto exit_device_put;
301 }
302
303 return 0;
304
305exit_device_put:
306 platform_device_put(sch56xx_pdev);
307
308 return err;
309}
310
311static int __init sch56xx_init(void)
312{
313 int err;
314 unsigned short address;
315 const char *name;
316
317 err = sch56xx_find(0x4e, &address, &name);
318 if (err)
319 err = sch56xx_find(0x2e, &address, &name);
320 if (err)
321 return err;
322
323 return sch56xx_device_add(address, name);
324}
325
326static void __exit sch56xx_exit(void)
327{
328 platform_device_unregister(sch56xx_pdev);
329}
330
331MODULE_DESCRIPTION("SMSC SCH56xx Hardware Monitoring Common Code");
332MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
333MODULE_LICENSE("GPL");
334
335module_init(sch56xx_init);
336module_exit(sch56xx_exit);