2 * Copyright (c) 2016-2018 Mellanox Technologies. All rights reserved.
3 * Copyright (c) 2016-2018 Vadim Pasternak <vadimp@mellanox.com>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the names of the copyright holders nor the names of its
14 * contributors may be used to endorse or promote products derived from
15 * this software without specific prior written permission.
17 * Alternatively, this software may be distributed under the terms of the
18 * GNU General Public License ("GPL") version 2 as published by the Free
19 * Software Foundation.
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
22 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
25 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31 * POSSIBILITY OF SUCH DAMAGE.
34 #include <linux/bitops.h>
35 #include <linux/device.h>
36 #include <linux/hwmon.h>
37 #include <linux/hwmon-sysfs.h>
38 #include <linux/i2c.h>
39 #include <linux/interrupt.h>
40 #include <linux/module.h>
41 #include <linux/of_device.h>
42 #include <linux/platform_data/mlxreg.h>
43 #include <linux/platform_device.h>
44 #include <linux/spinlock.h>
45 #include <linux/regmap.h>
46 #include <linux/workqueue.h>
48 /* Offset of event and mask registers from status register. */
49 #define MLXREG_HOTPLUG_EVENT_OFF 1
50 #define MLXREG_HOTPLUG_MASK_OFF 2
51 #define MLXREG_HOTPLUG_AGGR_MASK_OFF 1
53 /* ASIC health parameters. */
54 #define MLXREG_HOTPLUG_HEALTH_MASK 0x02
55 #define MLXREG_HOTPLUG_RST_CNTR 3
57 #define MLXREG_HOTPLUG_ATTRS_MAX 24
58 #define MLXREG_HOTPLUG_NOT_ASSERT 3
61 * struct mlxreg_hotplug_priv_data - platform private data:
62 * @irq: platform device interrupt number;
64 * @pdev: platform device;
65 * @plat: platform data;
66 * @regmap: register map handle;
67 * @dwork_irq: delayed work template;
69 * @hwmon: hwmon device;
70 * @mlxreg_hotplug_attr: sysfs attributes array;
71 * @mlxreg_hotplug_dev_attr: sysfs sensor device attribute array;
72 * @group: sysfs attribute group;
73 * @groups: list of sysfs attribute group for hwmon registration;
74 * @cell: location of top aggregation interrupt register;
75 * @mask: top aggregation interrupt common mask;
76 * @aggr_cache: last value of aggregation register status;
77 * @after_probe: flag indication probing completion;
78 * @not_asserted: number of entries in workqueue with no signal assertion;
80 struct mlxreg_hotplug_priv_data
{
83 struct platform_device
*pdev
;
84 struct mlxreg_hotplug_platform_data
*plat
;
85 struct regmap
*regmap
;
86 struct delayed_work dwork_irq
;
87 spinlock_t lock
; /* sync with interrupt */
89 struct attribute
*mlxreg_hotplug_attr
[MLXREG_HOTPLUG_ATTRS_MAX
+ 1];
90 struct sensor_device_attribute_2
91 mlxreg_hotplug_dev_attr
[MLXREG_HOTPLUG_ATTRS_MAX
];
92 struct attribute_group group
;
93 const struct attribute_group
*groups
[2];
101 static int mlxreg_hotplug_device_create(struct mlxreg_hotplug_priv_data
*priv
,
102 struct mlxreg_core_data
*data
)
104 struct mlxreg_core_hotplug_platform_data
*pdata
;
107 * Return if adapter number is negative. It could be in case hotplug
108 * event is not associated with hotplug device.
110 if (data
->hpdev
.nr
< 0)
113 pdata
= dev_get_platdata(&priv
->pdev
->dev
);
114 data
->hpdev
.adapter
= i2c_get_adapter(data
->hpdev
.nr
+
116 if (!data
->hpdev
.adapter
) {
117 dev_err(priv
->dev
, "Failed to get adapter for bus %d\n",
118 data
->hpdev
.nr
+ pdata
->shift_nr
);
122 data
->hpdev
.client
= i2c_new_device(data
->hpdev
.adapter
,
123 data
->hpdev
.brdinfo
);
124 if (!data
->hpdev
.client
) {
125 dev_err(priv
->dev
, "Failed to create client %s at bus %d at addr 0x%02x\n",
126 data
->hpdev
.brdinfo
->type
, data
->hpdev
.nr
+
127 pdata
->shift_nr
, data
->hpdev
.brdinfo
->addr
);
129 i2c_put_adapter(data
->hpdev
.adapter
);
130 data
->hpdev
.adapter
= NULL
;
137 static void mlxreg_hotplug_device_destroy(struct mlxreg_core_data
*data
)
139 if (data
->hpdev
.client
) {
140 i2c_unregister_device(data
->hpdev
.client
);
141 data
->hpdev
.client
= NULL
;
144 if (data
->hpdev
.adapter
) {
145 i2c_put_adapter(data
->hpdev
.adapter
);
146 data
->hpdev
.adapter
= NULL
;
150 static ssize_t
mlxreg_hotplug_attr_show(struct device
*dev
,
151 struct device_attribute
*attr
,
154 struct mlxreg_hotplug_priv_data
*priv
= dev_get_drvdata(dev
);
155 struct mlxreg_core_hotplug_platform_data
*pdata
;
156 int index
= to_sensor_dev_attr_2(attr
)->index
;
157 int nr
= to_sensor_dev_attr_2(attr
)->nr
;
158 struct mlxreg_core_item
*item
;
159 struct mlxreg_core_data
*data
;
163 pdata
= dev_get_platdata(&priv
->pdev
->dev
);
164 item
= pdata
->items
+ nr
;
165 data
= item
->data
+ index
;
167 ret
= regmap_read(priv
->regmap
, data
->reg
, ®val
);
172 regval
&= data
->mask
;
174 /* Bit = 0 : functional if item->inversed is true. */
176 regval
= !(regval
& data
->mask
);
178 regval
= !!(regval
& data
->mask
);
181 return sprintf(buf
, "%u\n", regval
);
184 #define PRIV_ATTR(i) priv->mlxreg_hotplug_attr[i]
185 #define PRIV_DEV_ATTR(i) priv->mlxreg_hotplug_dev_attr[i]
187 static int mlxreg_hotplug_attr_init(struct mlxreg_hotplug_priv_data
*priv
)
189 struct mlxreg_core_hotplug_platform_data
*pdata
;
190 struct mlxreg_core_item
*item
;
191 struct mlxreg_core_data
*data
;
192 int num_attrs
= 0, id
= 0, i
, j
;
194 pdata
= dev_get_platdata(&priv
->pdev
->dev
);
197 /* Go over all kinds of items - psu, pwr, fan. */
198 for (i
= 0; i
< pdata
->counter
; i
++, item
++) {
199 num_attrs
+= item
->count
;
201 /* Go over all units within the item. */
202 for (j
= 0; j
< item
->count
; j
++, data
++, id
++) {
203 PRIV_ATTR(id
) = &PRIV_DEV_ATTR(id
).dev_attr
.attr
;
204 PRIV_ATTR(id
)->name
= devm_kasprintf(&priv
->pdev
->dev
,
208 if (!PRIV_ATTR(id
)->name
) {
209 dev_err(priv
->dev
, "Memory allocation failed for attr %d.\n",
214 PRIV_DEV_ATTR(id
).dev_attr
.attr
.name
=
216 PRIV_DEV_ATTR(id
).dev_attr
.attr
.mode
= 0444;
217 PRIV_DEV_ATTR(id
).dev_attr
.show
=
218 mlxreg_hotplug_attr_show
;
219 PRIV_DEV_ATTR(id
).nr
= i
;
220 PRIV_DEV_ATTR(id
).index
= j
;
221 sysfs_attr_init(&PRIV_DEV_ATTR(id
).dev_attr
.attr
);
225 priv
->group
.attrs
= devm_kcalloc(&priv
->pdev
->dev
,
227 sizeof(struct attribute
*),
229 if (!priv
->group
.attrs
)
232 priv
->group
.attrs
= priv
->mlxreg_hotplug_attr
;
233 priv
->groups
[0] = &priv
->group
;
234 priv
->groups
[1] = NULL
;
240 mlxreg_hotplug_work_helper(struct mlxreg_hotplug_priv_data
*priv
,
241 struct mlxreg_core_item
*item
)
243 struct mlxreg_core_data
*data
;
244 u32 asserted
, regval
, bit
;
248 * Validate if item related to received signal type is valid.
249 * It should never happen, excepted the situation when some
250 * piece of hardware is broken. In such situation just produce
251 * error message and return. Caller must continue to handle the
252 * signals from other devices if any.
254 if (unlikely(!item
)) {
255 dev_err(priv
->dev
, "False signal: at offset:mask 0x%02x:0x%02x.\n",
256 item
->reg
, item
->mask
);
262 ret
= regmap_write(priv
->regmap
, item
->reg
+ MLXREG_HOTPLUG_MASK_OFF
,
268 ret
= regmap_read(priv
->regmap
, item
->reg
, ®val
);
272 /* Set asserted bits and save last status. */
273 regval
&= item
->mask
;
274 asserted
= item
->cache
^ regval
;
275 item
->cache
= regval
;
277 for_each_set_bit(bit
, (unsigned long *)&asserted
, 8) {
278 data
= item
->data
+ bit
;
279 if (regval
& BIT(bit
)) {
281 mlxreg_hotplug_device_destroy(data
);
283 mlxreg_hotplug_device_create(priv
, data
);
286 mlxreg_hotplug_device_create(priv
, data
);
288 mlxreg_hotplug_device_destroy(data
);
292 /* Acknowledge event. */
293 ret
= regmap_write(priv
->regmap
, item
->reg
+ MLXREG_HOTPLUG_EVENT_OFF
,
299 ret
= regmap_write(priv
->regmap
, item
->reg
+ MLXREG_HOTPLUG_MASK_OFF
,
304 dev_err(priv
->dev
, "Failed to complete workqueue.\n");
308 mlxreg_hotplug_health_work_helper(struct mlxreg_hotplug_priv_data
*priv
,
309 struct mlxreg_core_item
*item
)
311 struct mlxreg_core_data
*data
= item
->data
;
315 for (i
= 0; i
< item
->count
; i
++, data
++) {
317 ret
= regmap_write(priv
->regmap
, data
->reg
+
318 MLXREG_HOTPLUG_MASK_OFF
, 0);
323 ret
= regmap_read(priv
->regmap
, data
->reg
, ®val
);
327 regval
&= data
->mask
;
328 item
->cache
= regval
;
329 if (regval
== MLXREG_HOTPLUG_HEALTH_MASK
) {
330 if ((data
->health_cntr
++ == MLXREG_HOTPLUG_RST_CNTR
) ||
331 !priv
->after_probe
) {
332 mlxreg_hotplug_device_create(priv
, data
);
333 data
->attached
= true;
336 if (data
->attached
) {
337 mlxreg_hotplug_device_destroy(data
);
338 data
->attached
= false;
339 data
->health_cntr
= 0;
343 /* Acknowledge event. */
344 ret
= regmap_write(priv
->regmap
, data
->reg
+
345 MLXREG_HOTPLUG_EVENT_OFF
, 0);
350 ret
= regmap_write(priv
->regmap
, data
->reg
+
351 MLXREG_HOTPLUG_MASK_OFF
, data
->mask
);
358 dev_err(priv
->dev
, "Failed to complete workqueue.\n");
362 * mlxreg_hotplug_work_handler - performs traversing of device interrupt
363 * registers according to the below hierarchy schema:
365 * Aggregation registers (status/mask)
366 * PSU registers: *---*
367 * *-----------------* | |
368 * |status/event/mask|-----> | * |
369 * *-----------------* | |
370 * Power registers: | |
371 * *-----------------* | |
372 * |status/event/mask|-----> | * |
373 * *-----------------* | |
374 * FAN registers: | |--> CPU
375 * *-----------------* | |
376 * |status/event/mask|-----> | * |
377 * *-----------------* | |
378 * ASIC registers: | |
379 * *-----------------* | |
380 * |status/event/mask|-----> | * |
381 * *-----------------* | |
384 * In case some system changed are detected: FAN in/out, PSU in/out, power
385 * cable attached/detached, ASIC health good/bad, relevant device is created
388 static void mlxreg_hotplug_work_handler(struct work_struct
*work
)
390 struct mlxreg_core_hotplug_platform_data
*pdata
;
391 struct mlxreg_hotplug_priv_data
*priv
;
392 struct mlxreg_core_item
*item
;
393 u32 regval
, aggr_asserted
;
397 priv
= container_of(work
, struct mlxreg_hotplug_priv_data
,
399 pdata
= dev_get_platdata(&priv
->pdev
->dev
);
402 /* Mask aggregation event. */
403 ret
= regmap_write(priv
->regmap
, pdata
->cell
+
404 MLXREG_HOTPLUG_AGGR_MASK_OFF
, 0);
408 /* Read aggregation status. */
409 ret
= regmap_read(priv
->regmap
, pdata
->cell
, ®val
);
413 regval
&= pdata
->mask
;
414 aggr_asserted
= priv
->aggr_cache
^ regval
;
415 priv
->aggr_cache
= regval
;
418 * Handler is invoked, but no assertion is detected at top aggregation
419 * status level. Set aggr_asserted to mask value to allow handler extra
420 * run over all relevant signals to recover any missed signal.
422 if (priv
->not_asserted
== MLXREG_HOTPLUG_NOT_ASSERT
) {
423 priv
->not_asserted
= 0;
424 aggr_asserted
= pdata
->mask
;
429 /* Handle topology and health configuration changes. */
430 for (i
= 0; i
< pdata
->counter
; i
++, item
++) {
431 if (aggr_asserted
& item
->aggr_mask
) {
433 mlxreg_hotplug_health_work_helper(priv
, item
);
435 mlxreg_hotplug_work_helper(priv
, item
);
439 spin_lock_irqsave(&priv
->lock
, flags
);
442 * It is possible, that some signals have been inserted, while
443 * interrupt has been masked by mlxreg_hotplug_work_handler. In this
444 * case such signals will be missed. In order to handle these signals
445 * delayed work is canceled and work task re-scheduled for immediate
446 * execution. It allows to handle missed signals, if any. In other case
447 * work handler just validates that no new signals have been received
450 cancel_delayed_work(&priv
->dwork_irq
);
451 schedule_delayed_work(&priv
->dwork_irq
, 0);
453 spin_unlock_irqrestore(&priv
->lock
, flags
);
458 priv
->not_asserted
++;
459 /* Unmask aggregation event (no need acknowledge). */
460 ret
= regmap_write(priv
->regmap
, pdata
->cell
+
461 MLXREG_HOTPLUG_AGGR_MASK_OFF
, pdata
->mask
);
465 dev_err(priv
->dev
, "Failed to complete workqueue.\n");
468 static int mlxreg_hotplug_set_irq(struct mlxreg_hotplug_priv_data
*priv
)
470 struct mlxreg_core_hotplug_platform_data
*pdata
;
471 struct mlxreg_core_item
*item
;
474 pdata
= dev_get_platdata(&priv
->pdev
->dev
);
477 for (i
= 0; i
< pdata
->counter
; i
++, item
++) {
478 /* Clear group presense event. */
479 ret
= regmap_write(priv
->regmap
, item
->reg
+
480 MLXREG_HOTPLUG_EVENT_OFF
, 0);
484 /* Set group initial status as mask and unmask group event. */
485 if (item
->inversed
) {
486 item
->cache
= item
->mask
;
487 ret
= regmap_write(priv
->regmap
, item
->reg
+
488 MLXREG_HOTPLUG_MASK_OFF
,
495 /* Keep aggregation initial status as zero and unmask events. */
496 ret
= regmap_write(priv
->regmap
, pdata
->cell
+
497 MLXREG_HOTPLUG_AGGR_MASK_OFF
, pdata
->mask
);
501 /* Keep low aggregation initial status as zero and unmask events. */
502 if (pdata
->cell_low
) {
503 ret
= regmap_write(priv
->regmap
, pdata
->cell_low
+
504 MLXREG_HOTPLUG_AGGR_MASK_OFF
,
510 /* Invoke work handler for initializing hot plug devices setting. */
511 mlxreg_hotplug_work_handler(&priv
->dwork_irq
.work
);
515 dev_err(priv
->dev
, "Failed to set interrupts.\n");
516 enable_irq(priv
->irq
);
520 static void mlxreg_hotplug_unset_irq(struct mlxreg_hotplug_priv_data
*priv
)
522 struct mlxreg_core_hotplug_platform_data
*pdata
;
523 struct mlxreg_core_item
*item
;
524 struct mlxreg_core_data
*data
;
527 pdata
= dev_get_platdata(&priv
->pdev
->dev
);
529 disable_irq(priv
->irq
);
530 cancel_delayed_work_sync(&priv
->dwork_irq
);
532 /* Mask low aggregation event, if defined. */
534 regmap_write(priv
->regmap
, pdata
->cell_low
+
535 MLXREG_HOTPLUG_AGGR_MASK_OFF
, 0);
537 /* Mask aggregation event. */
538 regmap_write(priv
->regmap
, pdata
->cell
+ MLXREG_HOTPLUG_AGGR_MASK_OFF
,
541 /* Clear topology configurations. */
542 for (i
= 0; i
< pdata
->counter
; i
++, item
++) {
544 /* Mask group presense event. */
545 regmap_write(priv
->regmap
, data
->reg
+ MLXREG_HOTPLUG_MASK_OFF
,
547 /* Clear group presense event. */
548 regmap_write(priv
->regmap
, data
->reg
+
549 MLXREG_HOTPLUG_EVENT_OFF
, 0);
551 /* Remove all the attached devices in group. */
553 for (j
= 0; j
< count
; j
++, data
++)
554 mlxreg_hotplug_device_destroy(data
);
558 static irqreturn_t
mlxreg_hotplug_irq_handler(int irq
, void *dev
)
560 struct mlxreg_hotplug_priv_data
*priv
;
562 priv
= (struct mlxreg_hotplug_priv_data
*)dev
;
564 /* Schedule work task for immediate execution.*/
565 schedule_delayed_work(&priv
->dwork_irq
, 0);
570 static int mlxreg_hotplug_probe(struct platform_device
*pdev
)
572 struct mlxreg_core_hotplug_platform_data
*pdata
;
573 struct mlxreg_hotplug_priv_data
*priv
;
574 struct i2c_adapter
*deferred_adap
;
577 pdata
= dev_get_platdata(&pdev
->dev
);
579 dev_err(&pdev
->dev
, "Failed to get platform data.\n");
583 /* Defer probing if the necessary adapter is not configured yet. */
584 deferred_adap
= i2c_get_adapter(pdata
->deferred_nr
);
586 return -EPROBE_DEFER
;
587 i2c_put_adapter(deferred_adap
);
589 priv
= devm_kzalloc(&pdev
->dev
, sizeof(*priv
), GFP_KERNEL
);
594 priv
->irq
= pdata
->irq
;
596 priv
->irq
= platform_get_irq(pdev
, 0);
598 dev_err(&pdev
->dev
, "Failed to get platform irq: %d\n",
604 priv
->regmap
= pdata
->regmap
;
605 priv
->dev
= pdev
->dev
.parent
;
608 err
= devm_request_irq(&pdev
->dev
, priv
->irq
,
609 mlxreg_hotplug_irq_handler
, IRQF_TRIGGER_FALLING
610 | IRQF_SHARED
, "mlxreg-hotplug", priv
);
612 dev_err(&pdev
->dev
, "Failed to request irq: %d\n", err
);
616 disable_irq(priv
->irq
);
617 spin_lock_init(&priv
->lock
);
618 INIT_DELAYED_WORK(&priv
->dwork_irq
, mlxreg_hotplug_work_handler
);
619 /* Perform initial interrupts setup. */
620 mlxreg_hotplug_set_irq(priv
);
622 priv
->after_probe
= true;
623 dev_set_drvdata(&pdev
->dev
, priv
);
625 err
= mlxreg_hotplug_attr_init(priv
);
627 dev_err(&pdev
->dev
, "Failed to allocate attributes: %d\n",
632 priv
->hwmon
= devm_hwmon_device_register_with_groups(&pdev
->dev
,
633 "mlxreg_hotplug", priv
, priv
->groups
);
634 if (IS_ERR(priv
->hwmon
)) {
635 dev_err(&pdev
->dev
, "Failed to register hwmon device %ld\n",
636 PTR_ERR(priv
->hwmon
));
637 return PTR_ERR(priv
->hwmon
);
643 static int mlxreg_hotplug_remove(struct platform_device
*pdev
)
645 struct mlxreg_hotplug_priv_data
*priv
= dev_get_drvdata(&pdev
->dev
);
647 /* Clean interrupts setup. */
648 mlxreg_hotplug_unset_irq(priv
);
653 static struct platform_driver mlxreg_hotplug_driver
= {
655 .name
= "mlxreg-hotplug",
657 .probe
= mlxreg_hotplug_probe
,
658 .remove
= mlxreg_hotplug_remove
,
661 module_platform_driver(mlxreg_hotplug_driver
);
663 MODULE_AUTHOR("Vadim Pasternak <vadimp@mellanox.com>");
664 MODULE_DESCRIPTION("Mellanox regmap hotplug platform driver");
665 MODULE_LICENSE("Dual BSD/GPL");
666 MODULE_ALIAS("platform:mlxreg-hotplug");