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acpi_i2c.c revision 1.12 
      1 /* $NetBSD: acpi_i2c.c,v 1.12 2022/07/23 03:08:17 thorpej Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 2017, 2021 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Manuel Bouyer.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/cdefs.h>
     33 __KERNEL_RCSID(0, "$NetBSD: acpi_i2c.c,v 1.12 2022/07/23 03:08:17 thorpej Exp $");
     34 
     35 #include <dev/acpi/acpireg.h>
     36 #include <dev/acpi/acpivar.h>
     37 #include <dev/acpi/acpi_i2c.h>
     38 #include <dev/i2c/i2cvar.h>
     39 
     40 #include <sys/kmem.h>
     41 
     42 #define _COMPONENT	ACPI_BUS_COMPONENT
     43 ACPI_MODULE_NAME	("acpi_i2c")
     44 
     45 struct acpi_i2c_context {
     46 	uint16_t i2c_addr;
     47 };
     48 
     49 static ACPI_STATUS
     50 acpi_i2c_resource_parse_callback(ACPI_RESOURCE *res, void *context)
     51 {
     52 	struct acpi_i2c_context *i2cc = context;
     53 
     54 	switch (res->Type) {
     55 	case ACPI_RESOURCE_TYPE_END_TAG:
     56 		break;
     57 	case ACPI_RESOURCE_TYPE_SERIAL_BUS:
     58 		switch (res->Data.I2cSerialBus.Type) {
     59 		case ACPI_RESOURCE_SERIAL_TYPE_I2C:
     60 			i2cc->i2c_addr = res->Data.I2cSerialBus.SlaveAddress;
     61 			break;
     62 		}
     63 		break;
     64 	case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
     65 		break;
     66 	default:
     67 		printf("resource type 0x%x ignored\n", res->Type);
     68 	}
     69 	return_ACPI_STATUS(AE_OK);
     70 }
     71 
     72 static void
     73 acpi_enter_i2c_device(struct acpi_devnode *ad, prop_array_t array)
     74 {
     75 	prop_dictionary_t dev;
     76 	struct acpi_i2c_context i2cc;
     77 	ACPI_STATUS rv;
     78 	char *clist;
     79 	size_t clist_size;
     80 
     81 	memset(&i2cc, 0, sizeof(i2cc));
     82 	rv = AcpiWalkResources(ad->ad_handle, "_CRS",
     83 	     acpi_i2c_resource_parse_callback, &i2cc);
     84 	if (ACPI_FAILURE(rv)) {
     85 		aprint_error("ACPI: unable to get resources "
     86 		   "for %s: %s\n", ad->ad_name,
     87 		   AcpiFormatException(rv));
     88 		return;
     89 	}
     90 	if (i2cc.i2c_addr == 0)
     91 		return;
     92 	dev = prop_dictionary_create();
     93 	if (dev == NULL) {
     94 		aprint_error("ignoring device %s (no memory)\n",
     95 		    ad->ad_name);
     96 		return;
     97 	}
     98 	clist = acpi_pack_compat_list(ad, &clist_size);
     99 	if (clist == NULL) {
    100 		prop_object_release(dev);
    101 		aprint_error("ignoring device %s (no _HID or _CID)\n",
    102 		    ad->ad_name);
    103 		return;
    104 	}
    105 	prop_dictionary_set_string(dev, "name", ad->ad_name);
    106 	prop_dictionary_set_uint32(dev, "addr", i2cc.i2c_addr);
    107 	prop_dictionary_set_uint64(dev, "cookie", (uintptr_t)ad->ad_handle);
    108 	prop_dictionary_set_uint32(dev, "cookietype", I2C_COOKIE_ACPI);
    109 	prop_dictionary_set_data(dev, "compatible", clist, clist_size);
    110 	kmem_free(clist, clist_size);
    111 
    112 	prop_array_add(array, dev);
    113 	prop_object_release(dev);
    114 }
    115 
    116 prop_array_t
    117 acpi_enter_i2c_devs(device_t dev, struct acpi_devnode *devnode)
    118 {
    119 	struct acpi_devnode *ad;
    120 	prop_array_t array = prop_array_create();
    121 
    122 	if (array == NULL)
    123 		return NULL;
    124 
    125 	SIMPLEQ_FOREACH(ad, &devnode->ad_child_head, ad_child_list) {
    126 		if (ad->ad_devinfo->Type != ACPI_TYPE_DEVICE)
    127 			continue;
    128 		if (!acpi_device_present(ad->ad_handle))
    129 			continue;
    130 		acpi_enter_i2c_device(ad, array);
    131 	}
    132 
    133 	if (dev != NULL) {
    134 		acpi_claim_childdevs(dev, devnode);
    135 	}
    136 
    137 	return array;
    138 }
    139