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      1 /* $NetBSD: acpi_i2c.c,v 1.22 2025/09/18 02:51:04 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 "iic.h"
     33 
     34 #include <sys/cdefs.h>
     35 __KERNEL_RCSID(0, "$NetBSD: acpi_i2c.c,v 1.22 2025/09/18 02:51:04 thorpej Exp $");
     36 
     37 #include <sys/device.h>
     38 
     39 #include <dev/acpi/acpireg.h>
     40 #include <dev/acpi/acpivar.h>
     41 #include <dev/acpi/acpi_i2c.h>
     42 #include <external/bsd/acpica/dist/include/acinterp.h>
     43 #include <external/bsd/acpica/dist/include/amlcode.h>
     44 #include <dev/i2c/i2cvar.h>
     45 
     46 #include <sys/kmem.h>
     47 
     48 #define _COMPONENT	ACPI_BUS_COMPONENT
     49 ACPI_MODULE_NAME	("acpi_i2c")
     50 
     51 struct acpi_i2c_address_space_context {
     52 	ACPI_CONNECTION_INFO conn_info;	/* must be first */
     53 	i2c_tag_t tag;
     54 };
     55 
     56 static const struct device_compatible_entry hid_compat_data[] = {
     57 	{ .compat = "PNP0C50" },
     58 	DEVICE_COMPAT_EOL
     59 };
     60 
     61 #if NIIC > 0
     62 struct acpi_i2c_context {
     63 	uint16_t i2c_addr;
     64 	struct acpi_devnode *res_src;
     65 };
     66 #endif
     67 
     68 static struct acpi_devnode *
     69 acpi_i2c_resource_find_source(ACPI_RESOURCE_SOURCE *rs)
     70 {
     71 	ACPI_STATUS rv;
     72 	ACPI_HANDLE hdl;
     73 	struct acpi_devnode *ad;
     74 
     75 	if (rs->StringPtr == NULL) {
     76 		return NULL;
     77 	}
     78 
     79 	rv = AcpiGetHandle(NULL, rs->StringPtr, &hdl);
     80 	if (ACPI_FAILURE(rv)) {
     81 		printf("%s: couldn't lookup '%s': %s\n", __func__,
     82 		    rs->StringPtr, AcpiFormatException(rv));
     83 		return NULL;
     84 	}
     85 
     86 	SIMPLEQ_FOREACH(ad, &acpi_softc->sc_head, ad_list) {
     87 		if (ad->ad_handle == hdl) {
     88 			return ad;
     89 		}
     90 	}
     91 
     92 	printf("%s: no acpi devnode matching resource source '%s'\n",
     93 	    __func__, rs->StringPtr);
     94 	return NULL;
     95 }
     96 
     97 static ACPI_STATUS
     98 acpi_i2c_resource_parse_callback(ACPI_RESOURCE *res, void *context)
     99 {
    100 	struct acpi_i2c_context *i2cc = context;
    101 
    102 	switch (res->Type) {
    103 	case ACPI_RESOURCE_TYPE_END_TAG:
    104 		break;
    105 	case ACPI_RESOURCE_TYPE_SERIAL_BUS:
    106 		switch (res->Data.I2cSerialBus.Type) {
    107 		case ACPI_RESOURCE_SERIAL_TYPE_I2C:
    108 			i2cc->i2c_addr = res->Data.I2cSerialBus.SlaveAddress;
    109 			i2cc->res_src = acpi_i2c_resource_find_source(
    110 			    &res->Data.I2cSerialBus.ResourceSource);
    111 			break;
    112 		}
    113 		break;
    114 	case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
    115 		break;
    116 	default:
    117 		break;
    118 	}
    119 	return_ACPI_STATUS(AE_OK);
    120 }
    121 
    122 static void
    123 acpi_enter_i2c_device(struct acpi_devnode *ad, prop_array_t array)
    124 {
    125 	prop_dictionary_t dev;
    126 	struct acpi_i2c_context i2cc;
    127 	ACPI_STATUS rv;
    128 	char *clist;
    129 	size_t clist_size;
    130 	devhandle_t child_devhandle;
    131 
    132 	memset(&i2cc, 0, sizeof(i2cc));
    133 	rv = AcpiWalkResources(ad->ad_handle, "_CRS",
    134 	     acpi_i2c_resource_parse_callback, &i2cc);
    135 	if (ACPI_FAILURE(rv)) {
    136 		return;
    137 	}
    138 	if (i2cc.i2c_addr == 0)
    139 		return;
    140 	dev = prop_dictionary_create();
    141 	if (dev == NULL) {
    142 		aprint_error("ignoring device %s (no memory)\n",
    143 		    ad->ad_name);
    144 		return;
    145 	}
    146 	clist = acpi_pack_compat_list(ad, &clist_size);
    147 	if (clist == NULL) {
    148 		prop_object_release(dev);
    149 		aprint_error("ignoring device %s (no _HID or _CID)\n",
    150 		    ad->ad_name);
    151 		return;
    152 	}
    153 	prop_dictionary_set_string(dev, "name", ad->ad_name);
    154 	prop_dictionary_set_uint32(dev, "addr", i2cc.i2c_addr);
    155 	child_devhandle = devhandle_from_acpi(devhandle_invalid(),
    156 	    ad->ad_handle);
    157 	prop_dictionary_set_data(dev, "devhandle", &child_devhandle,
    158 	    sizeof(child_devhandle));
    159 	prop_dictionary_set_data(dev, "compatible", clist, clist_size);
    160 	kmem_free(clist, clist_size);
    161 
    162 	prop_array_add(array, dev);
    163 	prop_object_release(dev);
    164 }
    165 
    166 static void
    167 acpi_enter_i2chid_devs(device_t dev, struct acpi_devnode *devnode,
    168     prop_array_t array)
    169 {
    170 	struct acpi_devnode *ad;
    171 
    172 	KASSERT(dev != NULL);
    173 
    174 	SIMPLEQ_FOREACH(ad, &acpi_softc->sc_head, ad_list) {
    175 		struct acpi_attach_args aa = {
    176 			.aa_node = ad
    177 		};
    178 		struct acpi_i2c_context i2cc;
    179 		ACPI_STATUS rv;
    180 
    181 		if (!acpi_device_present(ad->ad_handle))
    182 			continue;
    183 		if (ad->ad_device != NULL)
    184 			continue;
    185 		if (acpi_compatible_match(&aa, hid_compat_data) == 0)
    186 			continue;
    187 
    188 		memset(&i2cc, 0, sizeof(i2cc));
    189 		rv = AcpiWalkResources(ad->ad_handle, "_CRS",
    190 		    acpi_i2c_resource_parse_callback, &i2cc);
    191 		if (ACPI_SUCCESS(rv) &&
    192 		    i2cc.i2c_addr != 0 &&
    193 		    i2cc.res_src == devnode) {
    194 			aprint_debug_dev(dev, "claiming %s\n", ad->ad_name);
    195 			ad->ad_device = dev;
    196 			acpi_claim_childdevs(dev, ad, NULL);
    197 			acpi_enter_i2c_device(ad, array);
    198 		}
    199 	}
    200 }
    201 
    202 prop_array_t
    203 acpi_copy_i2c_devs(device_t dev)
    204 {
    205 	struct acpi_devnode *ad;
    206 	ACPI_HANDLE *hdl = devhandle_to_acpi(device_handle(dev));
    207 	struct acpi_devnode *devnode = acpi_match_node(hdl);
    208 
    209 	if (devnode == NULL) {
    210 		aprint_error_dev(dev, "%s: no devnode matching handle\n",
    211 		    __func__);
    212 		return NULL;
    213 	}
    214 
    215 	prop_array_t array = prop_array_create();
    216 	if (array == NULL)
    217 		return NULL;
    218 
    219 	SIMPLEQ_FOREACH(ad, &devnode->ad_child_head, ad_child_list) {
    220 		if (ad->ad_devinfo->Type != ACPI_TYPE_DEVICE)
    221 			continue;
    222 		if (!acpi_device_present(ad->ad_handle))
    223 			continue;
    224 		acpi_enter_i2c_device(ad, array);
    225 	}
    226 
    227 	if (dev != NULL) {
    228 		acpi_claim_childdevs(dev, devnode, "_CRS");
    229 		acpi_claim_childdevs(dev, devnode, "_ADR");
    230 		acpi_enter_i2chid_devs(dev, devnode, array);
    231 	}
    232 
    233 	return array;
    234 }
    235 
    236 #if NIIC > 0
    237 static ACPI_STATUS
    238 acpi_i2c_gsb_init(ACPI_HANDLE region_hdl, UINT32 function,
    239     void *handler_ctx, void **region_ctx)
    240 {
    241 	if (function == ACPI_REGION_DEACTIVATE) {
    242 		*region_ctx = NULL;
    243 	} else {
    244 		*region_ctx = region_hdl;
    245 	}
    246 	return AE_OK;
    247 }
    248 
    249 static ACPI_STATUS
    250 acpi_i2c_gsb_handler(UINT32 function, ACPI_PHYSICAL_ADDRESS address,
    251     UINT32 bit_width, UINT64 *value, void *handler_ctx,
    252     void *region_ctx)
    253 {
    254 	ACPI_OPERAND_OBJECT *region_obj = region_ctx;
    255 	struct acpi_i2c_address_space_context *context = handler_ctx;
    256 	UINT8 *buf = ACPI_CAST_PTR(uint8_t, value);
    257 	ACPI_PHYSICAL_ADDRESS base_address;
    258 	ACPI_RESOURCE *res;
    259 	ACPI_STATUS rv;
    260 	ACPI_CONNECTION_INFO *conn_info = &context->conn_info;
    261 	i2c_tag_t tag = context->tag;
    262 	i2c_addr_t i2c_addr;
    263 	i2c_op_t op;
    264 	union {
    265 		uint8_t cmd8;
    266 		uint16_t cmd16;
    267 		uint32_t cmd32;
    268 	} cmd;
    269 	size_t buflen;
    270 	size_t cmdlen;
    271 	bool do_xfer = true;
    272 
    273 	if (region_obj->Region.Type != ACPI_TYPE_REGION) {
    274 		return AE_OK;
    275 	}
    276 
    277 	base_address = region_obj->Region.Address;
    278 	KASSERT(region_obj->Region.SpaceId == ACPI_ADR_SPACE_GSBUS);
    279 
    280 	rv = AcpiBufferToResource(conn_info->Connection, conn_info->Length,
    281 	    &res);
    282 	if (ACPI_FAILURE(rv)) {
    283 		return rv;
    284 	}
    285 	if (res->Type != ACPI_RESOURCE_TYPE_SERIAL_BUS ||
    286 	    res->Data.CommonSerialBus.Type != ACPI_RESOURCE_SERIAL_TYPE_I2C) {
    287 		return AE_TYPE;
    288 	}
    289 
    290 	i2c_addr = res->Data.I2cSerialBus.SlaveAddress;
    291 	if ((function & ACPI_IO_MASK) != 0) {
    292 		op = I2C_OP_WRITE_WITH_STOP;
    293 	} else {
    294 		op = I2C_OP_READ_WITH_STOP;
    295 	}
    296 
    297 #ifdef ACPI_I2C_DEBUG
    298 	UINT32 length;
    299 	rv = AcpiExGetProtocolBufferLength(function >> 16, &length);
    300 	if (ACPI_FAILURE(rv)) {
    301 		printf("%s AcpiExGetProtocolBufferLength failed: %s\n",
    302 		    __func__, AcpiFormatException(rv));
    303 		length = UINT32_MAX;
    304 	}
    305 	printf("%s %s: %s Attr %X Addr %.4X BaseAddr %.4X Length %.2X BitWidth %X BufLen %X",
    306 	       __func__, AcpiUtGetRegionName(region_obj->Region.SpaceId),
    307 	       (function & ACPI_IO_MASK) ? "Write" : "Read ",
    308 	       (UINT32) (function >> 16),
    309 	       (UINT32) address, (UINT32) base_address,
    310 	       length, bit_width, buf[1]);
    311 	printf(" [AccessLength %.2X Connection %p]\n",
    312 	       conn_info->AccessLength, conn_info->Connection);
    313 #endif
    314 
    315 	switch ((UINT32)(function >> 16)) {
    316 	case AML_FIELD_ATTRIB_QUICK:
    317 		cmdlen = 0;
    318 		buflen = 0;
    319 		break;
    320 	case AML_FIELD_ATTRIB_SEND_RECEIVE:
    321 		cmdlen = 0;
    322 		buflen = 1;
    323 		break;
    324 	case AML_FIELD_ATTRIB_BYTE:
    325 		cmdlen = bit_width / NBBY;
    326 		buflen = 1;
    327 		break;
    328 	case AML_FIELD_ATTRIB_WORD:
    329 		cmdlen = bit_width / NBBY;
    330 		buflen = 2;
    331 		break;
    332 	case AML_FIELD_ATTRIB_BYTES:
    333 		cmdlen = bit_width / NBBY;
    334 		buflen = buf[1];
    335 		break;
    336 	case AML_FIELD_ATTRIB_BLOCK:
    337 		cmdlen = bit_width / NBBY;
    338 		buflen = buf[1];
    339 		op |= I2C_OPMASK_BLKMODE;
    340 		break;
    341 	case AML_FIELD_ATTRIB_RAW_BYTES:
    342 	case AML_FIELD_ATTRIB_RAW_PROCESS_BYTES:
    343 	case AML_FIELD_ATTRIB_PROCESS_CALL:
    344 	default:
    345 		cmdlen = 0;
    346 		do_xfer = false;
    347 #ifdef ACPI_I2C_DEBUG
    348 		printf("field attrib 0x%x not supported\n",
    349 		    (UINT32)(function >> 16));
    350 #endif
    351 		break;
    352 	}
    353 
    354 	switch (cmdlen) {
    355 	case 0:
    356 	case 1:
    357 		cmd.cmd8 = (uint8_t)(base_address + address);
    358 		break;
    359 	case 2:
    360 		cmd.cmd16 = (uint16_t)(base_address + address);
    361 		break;
    362 	case 4:
    363 		cmd.cmd32 = (uint32_t)(base_address + address);
    364 		break;
    365 	default:
    366 		do_xfer = false;
    367 #ifdef ACPI_I2C_DEBUG
    368 		printf("cmdlen %zu not supported\n", cmdlen);
    369 #endif
    370 		break;
    371 	}
    372 
    373 	if (!do_xfer) {
    374 		buf[0] = EINVAL;
    375 	} else {
    376 		const int flags = I2C_F_POLL;
    377 		iic_acquire_bus(tag, flags);
    378 		buf[0] = iic_exec(tag, op, i2c_addr,
    379 				  &cmd, cmdlen, &buf[2], buflen, flags);
    380 		iic_release_bus(tag, flags);
    381 		if (buf[0] == 0) {
    382 			buf[1] = buflen;
    383 		}
    384 #ifdef ACPI_I2C_DEBUG
    385 		printf("%s iic_exec op %u addr 0x%x len %zu/%zu returned %d\n",
    386 		    __func__, op, res->Data.I2cSerialBus.SlaveAddress, cmdlen,
    387 		    buflen, buf[0]);
    388 #endif
    389 	}
    390 
    391 	ACPI_FREE(res);
    392 
    393 	return AE_OK;
    394 }
    395 #endif
    396 
    397 void
    398 acpi_i2c_register(device_t dev, i2c_tag_t tag)
    399 {
    400 #if NIIC > 0
    401 	ACPI_HANDLE hdl = devhandle_to_acpi(device_handle(dev));
    402 	struct acpi_i2c_address_space_context *context;
    403 	ACPI_STATUS rv;
    404 
    405 	context = kmem_zalloc(sizeof(*context), KM_SLEEP);
    406 	context->tag = tag;
    407 
    408 	rv = AcpiInstallAddressSpaceHandler(hdl,
    409 	    ACPI_ADR_SPACE_GSBUS, acpi_i2c_gsb_handler, acpi_i2c_gsb_init,
    410 	    context);
    411 	if (ACPI_FAILURE(rv)) {
    412 		aprint_error_dev(dev,
    413 		    "couldn't install address space handler: %s",
    414 		    AcpiFormatException(rv));
    415 	}
    416 #endif
    417 }
    418