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acpi_i2c.c revision 1.11.4.1 
      1 /* $NetBSD: acpi_i2c.c,v 1.11.4.1 2021/04/25 21:49:56 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 and Jason R. Thorpe.
      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 1.11.4.1 2021/04/25 21:49:56 thorpej Exp $");
     34 
     35 #include <dev/acpi/acpireg.h>
     36 #include <dev/acpi/acpivar.h>
     37 #include <dev/i2c/i2cvar.h>
     38 
     39 #include <sys/kmem.h>
     40 
     41 #define _COMPONENT	ACPI_BUS_COMPONENT
     42 ACPI_MODULE_NAME	("acpi_i2c")
     43 
     44 struct acpi_i2c_context {
     45 	uint16_t i2c_addr;
     46 };
     47 
     48 static ACPI_STATUS
     49 acpi_i2c_resource_parse_callback(ACPI_RESOURCE *res, void *context)
     50 {
     51 	struct acpi_i2c_context *i2cc = context;
     52 
     53 	switch (res->Type) {
     54 	case ACPI_RESOURCE_TYPE_END_TAG:
     55 		break;
     56 	case ACPI_RESOURCE_TYPE_SERIAL_BUS:
     57 		switch (res->Data.I2cSerialBus.Type) {
     58 		case ACPI_RESOURCE_SERIAL_TYPE_I2C:
     59 			i2cc->i2c_addr = res->Data.I2cSerialBus.SlaveAddress;
     60 			break;
     61 		}
     62 		break;
     63 	case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
     64 		break;
     65 	default:
     66 		printf("resource type 0x%x ignored\n", res->Type);
     67 	}
     68 	return_ACPI_STATUS(AE_OK);
     69 }
     70 
     71 static bool
     72 acpi_i2c_enumerate_device(device_t dev, struct acpi_devnode *ad,
     73     struct i2c_enumerate_devices_args * const args)
     74 {
     75 	char *clist;
     76 	size_t clist_size;
     77 	prop_dictionary_t props;
     78 	struct acpi_i2c_context i2cc;
     79 	bool cbrv;
     80 	ACPI_STATUS rv;
     81 
     82 	memset(&i2cc, 0, sizeof(i2cc));
     83 	rv = AcpiWalkResources(ad->ad_handle, "_CRS",
     84 	     acpi_i2c_resource_parse_callback, &i2cc);
     85 	if (ACPI_FAILURE(rv)) {
     86 		aprint_error("ACPI: unable to get resources "
     87 		   "for %s: %s\n", ad->ad_name,
     88 		   AcpiFormatException(rv));
     89 		return true;	/* keep enumerating */
     90 	}
     91 	if (i2cc.i2c_addr == 0)
     92 		return true;	/* keep enumerating */
     93 
     94 	clist = acpi_pack_compat_list(ad->ad_devinfo, &clist_size);
     95 	if (clist == NULL) {
     96 		aprint_error("ACPI: ignoring device %s (no _HID or _CID)\n",
     97 		    ad->ad_name);
     98 		return true;	/* keep enumerating */
     99 	}
    100 	props = prop_dictionary_create();
    101 
    102 	args->ia->ia_addr = i2cc.i2c_addr;
    103 	args->ia->ia_name = ad->ad_name;
    104 	args->ia->ia_clist = clist;
    105 	args->ia->ia_clist_size = clist_size;
    106 	args->ia->ia_prop = props;
    107 	args->ia->ia_devhandle = devhandle_from_acpi(ad->ad_handle);
    108 	args->ia->ia_cookie = (uint64_t)ad->ad_handle;	/* XXX */
    109 	args->ia->ia_cookietype = I2C_COOKIE_ACPI;	/* XXX */
    110 
    111 	cbrv = args->callback(dev, args);
    112 
    113 	prop_object_release(props);
    114 	kmem_free(clist, clist_size);
    115 
    116 	return cbrv;	/* callback decides if we keep enumerating */
    117 }
    118 
    119 static int
    120 acpi_i2c_enumerate_devices(device_t dev, devhandle_t call_handle, void *v)
    121 {
    122 	struct i2c_enumerate_devices_args *args = v;
    123 	struct acpi_devnode *ad, *devnode;
    124 	ACPI_HANDLE *hdl = devhandle_to_acpi(call_handle);
    125 
    126 	devnode = acpi_match_node(hdl);
    127 	if (devnode == NULL) {
    128 		aprint_verbose_dev(dev, "%s: no devnode matching handle\n",
    129 		    __func__);
    130 		return 0;
    131 	}
    132 
    133 	SIMPLEQ_FOREACH(ad, &devnode->ad_child_head, ad_child_list) {
    134 		if (ad->ad_devinfo->Type != ACPI_TYPE_DEVICE)
    135 			continue;
    136 		if (!acpi_device_present(ad->ad_handle))
    137 			continue;
    138 		if (!acpi_i2c_enumerate_device(dev, ad, args))
    139 			break;
    140 	}
    141 
    142 	acpi_claim_childdevs(dev, devnode);
    143 
    144 	return 0;
    145 }
    146 ACPI_DEVICE_CALL_REGISTER("i2c-enumerate-devices", acpi_i2c_enumerate_devices)
    147