xref: /openbmc/linux/drivers/leds/leds-ss4200.c (revision 0244ad00)
1 /*
2  * SS4200-E Hardware API
3  * Copyright (c) 2009, Intel Corporation.
4  * Copyright IBM Corporation, 2009
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms and conditions of the GNU General Public License,
8  * version 2, as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope it will be useful, but WITHOUT
11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13  * more details.
14  *
15  * You should have received a copy of the GNU General Public License along with
16  * this program; if not, write to the Free Software Foundation, Inc.,
17  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
18  *
19  * Author: Dave Hansen <dave@sr71.net>
20  */
21 
22 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
23 
24 #include <linux/dmi.h>
25 #include <linux/init.h>
26 #include <linux/ioport.h>
27 #include <linux/kernel.h>
28 #include <linux/leds.h>
29 #include <linux/module.h>
30 #include <linux/pci.h>
31 #include <linux/types.h>
32 #include <linux/uaccess.h>
33 
34 MODULE_AUTHOR("Rodney Girod <rgirod@confocus.com>, Dave Hansen <dave@sr71.net>");
35 MODULE_DESCRIPTION("Intel NAS/Home Server ICH7 GPIO Driver");
36 MODULE_LICENSE("GPL");
37 
38 /*
39  * ICH7 LPC/GPIO PCI Config register offsets
40  */
41 #define PMBASE		0x040
42 #define GPIO_BASE	0x048
43 #define GPIO_CTRL	0x04c
44 #define GPIO_EN		0x010
45 
46 /*
47  * The ICH7 GPIO register block is 64 bytes in size.
48  */
49 #define ICH7_GPIO_SIZE	64
50 
51 /*
52  * Define register offsets within the ICH7 register block.
53  */
54 #define GPIO_USE_SEL	0x000
55 #define GP_IO_SEL	0x004
56 #define GP_LVL		0x00c
57 #define GPO_BLINK	0x018
58 #define GPI_INV		0x030
59 #define GPIO_USE_SEL2	0x034
60 #define GP_IO_SEL2	0x038
61 #define GP_LVL2		0x03c
62 
63 /*
64  * PCI ID of the Intel ICH7 LPC Device within which the GPIO block lives.
65  */
66 static DEFINE_PCI_DEVICE_TABLE(ich7_lpc_pci_id) = {
67 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH7_0) },
68 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH7_1) },
69 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH7_30) },
70 	{ } /* NULL entry */
71 };
72 
73 MODULE_DEVICE_TABLE(pci, ich7_lpc_pci_id);
74 
75 static int __init ss4200_led_dmi_callback(const struct dmi_system_id *id)
76 {
77 	pr_info("detected '%s'\n", id->ident);
78 	return 1;
79 }
80 
81 static bool __initdata nodetect;
82 module_param_named(nodetect, nodetect, bool, 0);
83 MODULE_PARM_DESC(nodetect, "Skip DMI-based hardware detection");
84 
85 /*
86  * struct nas_led_whitelist - List of known good models
87  *
88  * Contains the known good models this driver is compatible with.
89  * When adding a new model try to be as strict as possible. This
90  * makes it possible to keep the false positives (the model is
91  * detected as working, but in reality it is not) as low as
92  * possible.
93  */
94 static struct dmi_system_id nas_led_whitelist[] __initdata = {
95 	{
96 		.callback = ss4200_led_dmi_callback,
97 		.ident = "Intel SS4200-E",
98 		.matches = {
99 			DMI_MATCH(DMI_SYS_VENDOR, "Intel"),
100 			DMI_MATCH(DMI_PRODUCT_NAME, "SS4200-E"),
101 			DMI_MATCH(DMI_PRODUCT_VERSION, "1.00.00")
102 		}
103 	},
104 	{}
105 };
106 
107 /*
108  * Base I/O address assigned to the Power Management register block
109  */
110 static u32 g_pm_io_base;
111 
112 /*
113  * Base I/O address assigned to the ICH7 GPIO register block
114  */
115 static u32 nas_gpio_io_base;
116 
117 /*
118  * When we successfully register a region, we are returned a resource.
119  * We use these to identify which regions we need to release on our way
120  * back out.
121  */
122 static struct resource *gp_gpio_resource;
123 
124 struct nasgpio_led {
125 	char *name;
126 	u32 gpio_bit;
127 	struct led_classdev led_cdev;
128 };
129 
130 /*
131  * gpio_bit(s) are the ICH7 GPIO bit assignments
132  */
133 static struct nasgpio_led nasgpio_leds[] = {
134 	{ .name = "hdd1:blue:sata",	.gpio_bit = 0 },
135 	{ .name = "hdd1:amber:sata",	.gpio_bit = 1 },
136 	{ .name = "hdd2:blue:sata",	.gpio_bit = 2 },
137 	{ .name = "hdd2:amber:sata",	.gpio_bit = 3 },
138 	{ .name = "hdd3:blue:sata",	.gpio_bit = 4 },
139 	{ .name = "hdd3:amber:sata",	.gpio_bit = 5 },
140 	{ .name = "hdd4:blue:sata",	.gpio_bit = 6 },
141 	{ .name = "hdd4:amber:sata",	.gpio_bit = 7 },
142 	{ .name = "power:blue:power",	.gpio_bit = 27},
143 	{ .name = "power:amber:power",  .gpio_bit = 28},
144 };
145 
146 #define NAS_RECOVERY	0x00000400	/* GPIO10 */
147 
148 static struct nasgpio_led *
149 led_classdev_to_nasgpio_led(struct led_classdev *led_cdev)
150 {
151 	return container_of(led_cdev, struct nasgpio_led, led_cdev);
152 }
153 
154 static struct nasgpio_led *get_led_named(char *name)
155 {
156 	int i;
157 	for (i = 0; i < ARRAY_SIZE(nasgpio_leds); i++) {
158 		if (strcmp(nasgpio_leds[i].name, name))
159 			continue;
160 		return &nasgpio_leds[i];
161 	}
162 	return NULL;
163 }
164 
165 /*
166  * This protects access to the gpio ports.
167  */
168 static DEFINE_SPINLOCK(nasgpio_gpio_lock);
169 
170 /*
171  * There are two gpio ports, one for blinking and the other
172  * for power.  @port tells us if we're doing blinking or
173  * power control.
174  *
175  * Caller must hold nasgpio_gpio_lock
176  */
177 static void __nasgpio_led_set_attr(struct led_classdev *led_cdev,
178 				   u32 port, u32 value)
179 {
180 	struct nasgpio_led *led = led_classdev_to_nasgpio_led(led_cdev);
181 	u32 gpio_out;
182 
183 	gpio_out = inl(nas_gpio_io_base + port);
184 	if (value)
185 		gpio_out |= (1<<led->gpio_bit);
186 	else
187 		gpio_out &= ~(1<<led->gpio_bit);
188 
189 	outl(gpio_out, nas_gpio_io_base + port);
190 }
191 
192 static void nasgpio_led_set_attr(struct led_classdev *led_cdev,
193 				 u32 port, u32 value)
194 {
195 	spin_lock(&nasgpio_gpio_lock);
196 	__nasgpio_led_set_attr(led_cdev, port, value);
197 	spin_unlock(&nasgpio_gpio_lock);
198 }
199 
200 static u32 nasgpio_led_get_attr(struct led_classdev *led_cdev, u32 port)
201 {
202 	struct nasgpio_led *led = led_classdev_to_nasgpio_led(led_cdev);
203 	u32 gpio_in;
204 
205 	spin_lock(&nasgpio_gpio_lock);
206 	gpio_in = inl(nas_gpio_io_base + port);
207 	spin_unlock(&nasgpio_gpio_lock);
208 	if (gpio_in & (1<<led->gpio_bit))
209 		return 1;
210 	return 0;
211 }
212 
213 /*
214  * There is actual brightness control in the hardware,
215  * but it is via smbus commands and not implemented
216  * in this driver.
217  */
218 static void nasgpio_led_set_brightness(struct led_classdev *led_cdev,
219 				       enum led_brightness brightness)
220 {
221 	u32 setting = 0;
222 	if (brightness >= LED_HALF)
223 		setting = 1;
224 	/*
225 	 * Hold the lock across both operations.  This ensures
226 	 * consistency so that both the "turn off blinking"
227 	 * and "turn light off" operations complete as a set.
228 	 */
229 	spin_lock(&nasgpio_gpio_lock);
230 	/*
231 	 * LED class documentation asks that past blink state
232 	 * be disabled when brightness is turned to zero.
233 	 */
234 	if (brightness == 0)
235 		__nasgpio_led_set_attr(led_cdev, GPO_BLINK, 0);
236 	__nasgpio_led_set_attr(led_cdev, GP_LVL, setting);
237 	spin_unlock(&nasgpio_gpio_lock);
238 }
239 
240 static int nasgpio_led_set_blink(struct led_classdev *led_cdev,
241 				 unsigned long *delay_on,
242 				 unsigned long *delay_off)
243 {
244 	u32 setting = 1;
245 	if (!(*delay_on == 0 && *delay_off == 0) &&
246 	    !(*delay_on == 500 && *delay_off == 500))
247 		return -EINVAL;
248 	/*
249 	 * These are very approximate.
250 	 */
251 	*delay_on = 500;
252 	*delay_off = 500;
253 
254 	nasgpio_led_set_attr(led_cdev, GPO_BLINK, setting);
255 
256 	return 0;
257 }
258 
259 
260 /*
261  * Initialize the ICH7 GPIO registers for NAS usage.  The BIOS should have
262  * already taken care of this, but we will do so in a non destructive manner
263  * so that we have what we need whether the BIOS did it or not.
264  */
265 static int ich7_gpio_init(struct device *dev)
266 {
267 	int i;
268 	u32 config_data = 0;
269 	u32 all_nas_led = 0;
270 
271 	for (i = 0; i < ARRAY_SIZE(nasgpio_leds); i++)
272 		all_nas_led |= (1<<nasgpio_leds[i].gpio_bit);
273 
274 	spin_lock(&nasgpio_gpio_lock);
275 	/*
276 	 * We need to enable all of the GPIO lines used by the NAS box,
277 	 * so we will read the current Use Selection and add our usage
278 	 * to it.  This should be benign with regard to the original
279 	 * BIOS configuration.
280 	 */
281 	config_data = inl(nas_gpio_io_base + GPIO_USE_SEL);
282 	dev_dbg(dev, ": Data read from GPIO_USE_SEL = 0x%08x\n", config_data);
283 	config_data |= all_nas_led + NAS_RECOVERY;
284 	outl(config_data, nas_gpio_io_base + GPIO_USE_SEL);
285 	config_data = inl(nas_gpio_io_base + GPIO_USE_SEL);
286 	dev_dbg(dev, ": GPIO_USE_SEL = 0x%08x\n\n", config_data);
287 
288 	/*
289 	 * The LED GPIO outputs need to be configured for output, so we
290 	 * will ensure that all LED lines are cleared for output and the
291 	 * RECOVERY line ready for input.  This too should be benign with
292 	 * regard to BIOS configuration.
293 	 */
294 	config_data = inl(nas_gpio_io_base + GP_IO_SEL);
295 	dev_dbg(dev, ": Data read from GP_IO_SEL = 0x%08x\n",
296 					config_data);
297 	config_data &= ~all_nas_led;
298 	config_data |= NAS_RECOVERY;
299 	outl(config_data, nas_gpio_io_base + GP_IO_SEL);
300 	config_data = inl(nas_gpio_io_base + GP_IO_SEL);
301 	dev_dbg(dev, ": GP_IO_SEL = 0x%08x\n", config_data);
302 
303 	/*
304 	 * In our final system, the BIOS will initialize the state of all
305 	 * of the LEDs.  For now, we turn them all off (or Low).
306 	 */
307 	config_data = inl(nas_gpio_io_base + GP_LVL);
308 	dev_dbg(dev, ": Data read from GP_LVL = 0x%08x\n", config_data);
309 	/*
310 	 * In our final system, the BIOS will initialize the blink state of all
311 	 * of the LEDs.  For now, we turn blink off for all of them.
312 	 */
313 	config_data = inl(nas_gpio_io_base + GPO_BLINK);
314 	dev_dbg(dev, ": Data read from GPO_BLINK = 0x%08x\n", config_data);
315 
316 	/*
317 	 * At this moment, I am unsure if anything needs to happen with GPI_INV
318 	 */
319 	config_data = inl(nas_gpio_io_base + GPI_INV);
320 	dev_dbg(dev, ": Data read from GPI_INV = 0x%08x\n", config_data);
321 
322 	spin_unlock(&nasgpio_gpio_lock);
323 	return 0;
324 }
325 
326 static void ich7_lpc_cleanup(struct device *dev)
327 {
328 	/*
329 	 * If we were given exclusive use of the GPIO
330 	 * I/O Address range, we must return it.
331 	 */
332 	if (gp_gpio_resource) {
333 		dev_dbg(dev, ": Releasing GPIO I/O addresses\n");
334 		release_region(nas_gpio_io_base, ICH7_GPIO_SIZE);
335 		gp_gpio_resource = NULL;
336 	}
337 }
338 
339 /*
340  * The OS has determined that the LPC of the Intel ICH7 Southbridge is present
341  * so we can retrive the required operational information and prepare the GPIO.
342  */
343 static struct pci_dev *nas_gpio_pci_dev;
344 static int ich7_lpc_probe(struct pci_dev *dev,
345 				    const struct pci_device_id *id)
346 {
347 	int status;
348 	u32 gc = 0;
349 
350 	status = pci_enable_device(dev);
351 	if (status) {
352 		dev_err(&dev->dev, "pci_enable_device failed\n");
353 		return -EIO;
354 	}
355 
356 	nas_gpio_pci_dev = dev;
357 	status = pci_read_config_dword(dev, PMBASE, &g_pm_io_base);
358 	if (status)
359 		goto out;
360 	g_pm_io_base &= 0x00000ff80;
361 
362 	status = pci_read_config_dword(dev, GPIO_CTRL, &gc);
363 	if (!(GPIO_EN & gc)) {
364 		status = -EEXIST;
365 		dev_info(&dev->dev,
366 			   "ERROR: The LPC GPIO Block has not been enabled.\n");
367 		goto out;
368 	}
369 
370 	status = pci_read_config_dword(dev, GPIO_BASE, &nas_gpio_io_base);
371 	if (0 > status) {
372 		dev_info(&dev->dev, "Unable to read GPIOBASE.\n");
373 		goto out;
374 	}
375 	dev_dbg(&dev->dev, ": GPIOBASE = 0x%08x\n", nas_gpio_io_base);
376 	nas_gpio_io_base &= 0x00000ffc0;
377 
378 	/*
379 	 * Insure that we have exclusive access to the GPIO I/O address range.
380 	 */
381 	gp_gpio_resource = request_region(nas_gpio_io_base, ICH7_GPIO_SIZE,
382 					  KBUILD_MODNAME);
383 	if (NULL == gp_gpio_resource) {
384 		dev_info(&dev->dev,
385 			 "ERROR Unable to register GPIO I/O addresses.\n");
386 		status = -1;
387 		goto out;
388 	}
389 
390 	/*
391 	 * Initialize the GPIO for NAS/Home Server Use
392 	 */
393 	ich7_gpio_init(&dev->dev);
394 
395 out:
396 	if (status) {
397 		ich7_lpc_cleanup(&dev->dev);
398 		pci_disable_device(dev);
399 	}
400 	return status;
401 }
402 
403 static void ich7_lpc_remove(struct pci_dev *dev)
404 {
405 	ich7_lpc_cleanup(&dev->dev);
406 	pci_disable_device(dev);
407 }
408 
409 /*
410  * pci_driver structure passed to the PCI modules
411  */
412 static struct pci_driver nas_gpio_pci_driver = {
413 	.name = KBUILD_MODNAME,
414 	.id_table = ich7_lpc_pci_id,
415 	.probe = ich7_lpc_probe,
416 	.remove = ich7_lpc_remove,
417 };
418 
419 static struct led_classdev *get_classdev_for_led_nr(int nr)
420 {
421 	struct nasgpio_led *nas_led = &nasgpio_leds[nr];
422 	struct led_classdev *led = &nas_led->led_cdev;
423 	return led;
424 }
425 
426 
427 static void set_power_light_amber_noblink(void)
428 {
429 	struct nasgpio_led *amber = get_led_named("power:amber:power");
430 	struct nasgpio_led *blue = get_led_named("power:blue:power");
431 
432 	if (!amber || !blue)
433 		return;
434 	/*
435 	 * LED_OFF implies disabling future blinking
436 	 */
437 	pr_debug("setting blue off and amber on\n");
438 
439 	nasgpio_led_set_brightness(&blue->led_cdev, LED_OFF);
440 	nasgpio_led_set_brightness(&amber->led_cdev, LED_FULL);
441 }
442 
443 static ssize_t nas_led_blink_show(struct device *dev,
444 				  struct device_attribute *attr, char *buf)
445 {
446 	struct led_classdev *led = dev_get_drvdata(dev);
447 	int blinking = 0;
448 	if (nasgpio_led_get_attr(led, GPO_BLINK))
449 		blinking = 1;
450 	return sprintf(buf, "%u\n", blinking);
451 }
452 
453 static ssize_t nas_led_blink_store(struct device *dev,
454 				   struct device_attribute *attr,
455 				   const char *buf, size_t size)
456 {
457 	int ret;
458 	struct led_classdev *led = dev_get_drvdata(dev);
459 	unsigned long blink_state;
460 
461 	ret = kstrtoul(buf, 10, &blink_state);
462 	if (ret)
463 		return ret;
464 
465 	nasgpio_led_set_attr(led, GPO_BLINK, blink_state);
466 
467 	return size;
468 }
469 
470 static DEVICE_ATTR(blink, 0644, nas_led_blink_show, nas_led_blink_store);
471 
472 static int register_nasgpio_led(int led_nr)
473 {
474 	int ret;
475 	struct nasgpio_led *nas_led = &nasgpio_leds[led_nr];
476 	struct led_classdev *led = get_classdev_for_led_nr(led_nr);
477 
478 	led->name = nas_led->name;
479 	led->brightness = LED_OFF;
480 	if (nasgpio_led_get_attr(led, GP_LVL))
481 		led->brightness = LED_FULL;
482 	led->brightness_set = nasgpio_led_set_brightness;
483 	led->blink_set = nasgpio_led_set_blink;
484 	ret = led_classdev_register(&nas_gpio_pci_dev->dev, led);
485 	if (ret)
486 		return ret;
487 	ret = device_create_file(led->dev, &dev_attr_blink);
488 	if (ret)
489 		led_classdev_unregister(led);
490 	return ret;
491 }
492 
493 static void unregister_nasgpio_led(int led_nr)
494 {
495 	struct led_classdev *led = get_classdev_for_led_nr(led_nr);
496 	led_classdev_unregister(led);
497 	device_remove_file(led->dev, &dev_attr_blink);
498 }
499 /*
500  * module load/initialization
501  */
502 static int __init nas_gpio_init(void)
503 {
504 	int i;
505 	int ret = 0;
506 	int nr_devices = 0;
507 
508 	nr_devices = dmi_check_system(nas_led_whitelist);
509 	if (nodetect) {
510 		pr_info("skipping hardware autodetection\n");
511 		pr_info("Please send 'dmidecode' output to dave@sr71.net\n");
512 		nr_devices++;
513 	}
514 
515 	if (nr_devices <= 0) {
516 		pr_info("no LED devices found\n");
517 		return -ENODEV;
518 	}
519 
520 	pr_info("registering PCI driver\n");
521 	ret = pci_register_driver(&nas_gpio_pci_driver);
522 	if (ret)
523 		return ret;
524 	for (i = 0; i < ARRAY_SIZE(nasgpio_leds); i++) {
525 		ret = register_nasgpio_led(i);
526 		if (ret)
527 			goto out_err;
528 	}
529 	/*
530 	 * When the system powers on, the BIOS leaves the power
531 	 * light blue and blinking.  This will turn it solid
532 	 * amber once the driver is loaded.
533 	 */
534 	set_power_light_amber_noblink();
535 	return 0;
536 out_err:
537 	for (i--; i >= 0; i--)
538 		unregister_nasgpio_led(i);
539 	pci_unregister_driver(&nas_gpio_pci_driver);
540 	return ret;
541 }
542 
543 /*
544  * module unload
545  */
546 static void __exit nas_gpio_exit(void)
547 {
548 	int i;
549 	pr_info("Unregistering driver\n");
550 	for (i = 0; i < ARRAY_SIZE(nasgpio_leds); i++)
551 		unregister_nasgpio_led(i);
552 	pci_unregister_driver(&nas_gpio_pci_driver);
553 }
554 
555 module_init(nas_gpio_init);
556 module_exit(nas_gpio_exit);
557