ec.c

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     */
    object_name[2] = hex[((ec_q->data >> 4) & 0x0F)];
    object_name[3] = hex[(ec_q->data & 0x0F)];

    DEBUG_PRINT(ACPI_INFO, ("Read query data[0x%02x] from ec - evaluating [%s].\n", ec_q->data, object_name));

    status = acpi_evaluate_object(ec_q->ec->acpi_handle, object_name, NULL, NULL);

    kfree(ec_q);

    return_VOID;
}

/*
 * handle GPE
 */
static void
ec_gpe_handler(void *context)
{
    ACPI_STATUS             status = AE_OK;
    ec_context_t            *ec = (ec_context_t *) context;
    EC_QUERY_DATA           *ec_q = NULL;
    EC_STATUS               ec_status = 0;

    FUNCTION_TRACE("ec_gpe_handler");

    if (!ec) {
        DEBUG_PRINT(ACPI_INFO, ("Invalid (NULL) context.\n"));
        return_VOID;
    }

    // GET SPINLOCK!

    /*
     * EC_SCI?
     * -------
     * Check the EC_SCI bit to see if this is an EC_SCI event.  If not (e.g.
     * OBF/IBE) just return, as we already poll to detect these events.
     */
    ec_status = acpi_os_in8(ec->status_port);
    DEBUG_PRINT(ACPI_INFO, ("EC Status Register: [0x%02x]\n", ec_status));
    if (!(ec_status & EC_FLAG_SCI))
        return_VOID;

    DEBUG_PRINT(ACPI_INFO, ("EC_SCI detected - running QUERY.\n"));

    // TODO: Need GFP_ATOMIC 'switch' for OSL interface...
    ec_q = kmalloc(sizeof(EC_QUERY_DATA), GFP_ATOMIC);
    if (!ec_q) {
        DEBUG_PRINT(ACPI_INFO, ("Memory allocation failure.\n"));
        return_VOID;
    }

    ec_q->ec = ec;
    ec_q->data = 0;

    /*
     * Run Query:
     * ----------
     * Query the EC to find out which _Qxx method we need to evaluate.
     * Note that successful completion of the query causes the EC_SCI
     * bit to be cleared (and thus clearing the interrupt source).
     */
    status = ec_io_write(ec, ec->status_port, EC_COMMAND_QUERY, EC_EVENT_OUTPUT_BUFFER_FULL);
    if (ACPI_FAILURE(status)) {
        DEBUG_PRINT(ACPI_WARN, ("Unable to send 'query command' to EC.\n"));
        goto End;
    }

    status = ec_io_read(ec, ec->data_port, &(ec_q->data), EC_EVENT_NONE);
    if (ACPI_FAILURE(status)) {
        DEBUG_PRINT(ACPI_WARN, ("Error reading query data.\n"));
        goto End;
    }

    // RELEASE SPINLOCK!

    if (!ec_q->data) {
        DEBUG_PRINT(ACPI_WARN, ("Spurious EC SCI detected.\n"));
        status = AE_ERROR;
        goto End;
    }

    /*
     * Defer _Qxx Execution:
     * ---------------------
     * Can't evaluate this method now 'cause we're at interrupt-level.
     */
    status = acpi_os_queue_for_execution(OSD_PRIORITY_GPE, ec_query_handler, ec_q);
    if (ACPI_FAILURE(status)) {
        DEBUG_PRINT(ACPI_ERROR, ("Unable to defer _Qxx method evaluation.\n"));
        goto End;
    }

End:
    if (ACPI_FAILURE(status))
        kfree(ec_q);
    
    return_VOID;
}

static ACPI_STATUS
ec_region_setup (
    ACPI_HANDLE handle,
    u32 function,
    void *handler_context,
    void **region_context)
{
	FUNCTION_TRACE("acpi_ec_region_setup");

	printk("acpi_ec_region_setup\n");

	if (function == ACPI_REGION_DEACTIVATE)
	{
		if (*region_context)
		{
			acpi_cm_free (*region_context);
			*region_context = NULL;
		}

		return_ACPI_STATUS (AE_OK);
	}

	*region_context = NULL;

	return_ACPI_STATUS (AE_OK);
}

/*****************************************************************************
 * 
 * FUNCTION:    ec_region_handler
 *
 * PARAMETERS:  function            - Read or Write operation
 *              address             - Where in the space to read or write
 *              bit_width            - Field width in bits (8, 16, or 32)
 *              value               - Pointer to in or out value
 *              context             - context pointer
 *
 * RETURN:      <TBD>
 *
 * DESCRIPTION: Handler for the Embedded Controller (EC) address space 
 *              (Op Region)
 *
 ****************************************************************************/

static ACPI_STATUS
ec_region_handler (
    UINT32                  function,
    ACPI_PHYSICAL_ADDRESS   address,
    UINT32                  bit_width,
    UINT32                  *value,
    void                    *handler_context,
    void                    *region_context)
{
    ACPI_STATUS             status = AE_OK;
    ec_context_t              *ec = NULL;
    EC_REQUEST              ec_request;

    FUNCTION_TRACE("ec_space_handler");

    if (address > 0xFF || bit_width != 8 || !value || !handler_context)
        return_ACPI_STATUS(AE_BAD_PARAMETER);

    ec = (ec_context_t*)handler_context;

    switch (function) {

    case ADDRESS_SPACE_READ:
        ec_request.command = EC_COMMAND_READ;
        ec_request.address = address;
        ec_request.data = 0;
        break;

    case ADDRESS_SPACE_WRITE:
        ec_request.command = EC_COMMAND_WRITE;
        ec_request.address = address;
        ec_request.data = (UINT8)(*value);
        break;

    default:
        DEBUG_PRINT(ACPI_WARN, ("Received request with invalid function [0x%08X].\n", function));
        return_ACPI_STATUS(AE_BAD_PARAMETER);
        break;
    }

    DEBUG_PRINT(ACPI_INFO, ("device[ec] command[0x%02X] address[0x%02X] data[0x%02X]\n", ec_request.command, ec_request.address, ec_request.data));

    /*
     * Perform the Transaction.
     */
    status = ec_transaction(ec, &ec_request);
    if (ACPI_SUCCESS(status))
        (*value) = (UINT32)ec_request.data;

    return_ACPI_STATUS(status);
}

/*
 * Get Embedded Controller information
 */
static ACPI_STATUS
found_ec(
	ACPI_HANDLE handle,
	u32 level, 
	void *ctx, 
	void **value)
{
	ACPI_STATUS status;
	ACPI_OBJECT obj;
	ACPI_BUFFER buf;
	RESOURCE *res;
	ec_context_t *ec_cxt;

	buf.length = 0;
	buf.pointer = NULL;
	if (acpi_get_current_resources(handle, &buf) != AE_BUFFER_OVERFLOW)
		return AE_OK;

	buf.pointer = kmalloc(buf.length, GFP_KERNEL);
	if (!buf.pointer)
		return AE_NO_MEMORY;

	if (!ACPI_SUCCESS(acpi_get_current_resources(handle, &buf))) {
		kfree(buf.pointer);
		return AE_OK;
	}

	ec_cxt = kmalloc(sizeof(ec_context_t), GFP_KERNEL);
	if (!ec_cxt) {
		kfree(buf.pointer);
		return AE_NO_MEMORY;
	}

	ec_cxt->acpi_handle = handle;

	res = (RESOURCE*) buf.pointer;
	ec_cxt->data_port = res->data.io.min_base_address;
	res = NEXT_RESOURCE(res);
	ec_cxt->status_port = (int) res->data.io.min_base_address;

	kfree(buf.pointer);

	/* determine GPE bit */
	/* BUG: in acpi 2.0 this could return a package */
	buf.length = sizeof(obj);
	buf.pointer = &obj;
	if (!ACPI_SUCCESS(acpi_evaluate_object(handle, "_GPE", NULL, &buf))
		|| obj.type != ACPI_TYPE_NUMBER)
		return AE_OK;

	ec_cxt->gpe_bit = obj.number.value;

	/* determine if we need the Global Lock when accessing */
	buf.length = sizeof(obj);
	buf.pointer = &obj;

	status = acpi_evaluate_object(handle, "_GLK", NULL, &buf);
	if (status == AE_NOT_FOUND)
		ec_cxt->need_global_lock = 0;
	else if (!ACPI_SUCCESS(status) || obj.type != ACPI_TYPE_NUMBER) {
		DEBUG_PRINT(ACPI_ERROR, ("_GLK failed\n"));
		return AE_OK;
	}

	ec_cxt->need_global_lock = obj.number.value;

	printk(KERN_INFO "ACPI: found EC @ (0x%02x,0x%02x,gpe %d GL %d)\n",
		ec_cxt->data_port, ec_cxt->status_port, ec_cxt->gpe_bit,
		ec_cxt->need_global_lock);

	if (!ACPI_SUCCESS(acpi_install_gpe_handler(
		ec_cxt->gpe_bit,
		ACPI_EVENT_EDGE_TRIGGERED,
		ec_gpe_handler,
		ec_cxt))) {
		
		REPORT_ERROR(("Could not install GPE handler for EC.\n"));
		return AE_OK;
	}

	status = acpi_install_address_space_handler (handle, ADDRESS_SPACE_EC, 
		    ec_region_handler, ec_region_setup, ec_cxt);

	if (!ACPI_SUCCESS(status)) {
		REPORT_ERROR(("Could not install EC address "
			"space handler, error %s\n", acpi_cm_format_exception (status)));
	}
	
	return AE_OK;
}

int
acpi_ec_init(void)
{
	acpi_get_devices(ACPI_EC_HID, 
			found_ec,
			NULL,
			NULL);

	return 0;
}

int
acpi_ec_terminate(void)
{
	/* TODO */	
	/* walk list of EC's */
	/* free their context and release resources */
	return 0;
}