path: root/drivers/greybus/interface.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Greybus interface code
 *
 * Copyright 2014 Google Inc.
 * Copyright 2014 Linaro Ltd.
 */

#include <linux/delay.h>
#include <linux/greybus.h>

#include "greybus_trace.h"

#define GB_INTERFACE_MODE_SWITCH_TIMEOUT	2000

#define GB_INTERFACE_DEVICE_ID_BAD	0xff

#define GB_INTERFACE_AUTOSUSPEND_MS			3000

/* Time required for interface to enter standby before disabling REFCLK */
#define GB_INTERFACE_SUSPEND_HIBERNATE_DELAY_MS			20

/* Don't-care selector index */
#define DME_SELECTOR_INDEX_NULL		0

/* DME attributes */
/* FIXME: remove ES2 support and DME_T_TST_SRC_INCREMENT */
#define DME_T_TST_SRC_INCREMENT		0x4083

#define DME_DDBL1_MANUFACTURERID	0x5003
#define DME_DDBL1_PRODUCTID		0x5004

#define DME_TOSHIBA_GMP_VID		0x6000
#define DME_TOSHIBA_GMP_PID		0x6001
#define DME_TOSHIBA_GMP_SN0		0x6002
#define DME_TOSHIBA_GMP_SN1		0x6003
#define DME_TOSHIBA_GMP_INIT_STATUS	0x6101

/* DDBL1 Manufacturer and Product ids */
#define TOSHIBA_DMID			0x0126
#define TOSHIBA_ES2_BRIDGE_DPID		0x1000
#define TOSHIBA_ES3_APBRIDGE_DPID	0x1001
#define TOSHIBA_ES3_GBPHY_DPID	0x1002

static int gb_interface_hibernate_link(struct gb_interface *intf);
static int gb_interface_refclk_set(struct gb_interface *intf, bool enable);

static int gb_interface_dme_attr_get(struct gb_interface *intf,
				     u16 attr, u32 *val)
{
	return gb_svc_dme_peer_get(intf->hd->svc, intf->interface_id,
					attr, DME_SELECTOR_INDEX_NULL, val);
}

static int gb_interface_read_ara_dme(struct gb_interface *intf)
{
	u32 sn0, sn1;
	int ret;

	/*
	 * Unless this is a Toshiba bridge, bail out until we have defined
	 * standard GMP attributes.
	 */
	if (intf->ddbl1_manufacturer_id != TOSHIBA_DMID) {
		dev_err(&intf->dev, "unknown manufacturer %08x\n",
			intf->ddbl1_manufacturer_id);
		return -ENODEV;
	}

	ret = gb_interface_dme_attr_get(intf, DME_TOSHIBA_GMP_VID,
					&intf->vendor_id);
	if (ret)
		return ret;

	ret = gb_interface_dme_attr_get(intf, DME_TOSHIBA_GMP_PID,
					&intf->product_id);
	if (ret)
		return ret;

	ret = gb_interface_dme_attr_get(intf, DME_TOSHIBA_GMP_SN0, &sn0);
	if (ret)
		return ret;

	ret = gb_interface_dme_attr_get(intf, DME_TOSHIBA_GMP_SN1, &sn1);
	if (ret)
		return ret;

	intf->serial_number = (u64)sn1 << 32 | sn0;

	return 0;
}

static int gb_interface_read_dme(struct gb_interface *intf)
{
	int ret;

	/* DME attributes have already been read */
	if (intf->dme_read)
		return 0;

	ret = gb_interface_dme_attr_get(intf, DME_DDBL1_MANUFACTURERID,
					&intf->ddbl1_manufacturer_id);
	if (ret)
		return ret;

	ret = gb_interface_dme_attr_get(intf, DME_DDBL1_PRODUCTID,
					&intf->ddbl1_product_id);
	if (ret)
		return ret;

	if (intf->ddbl1_manufacturer_id == TOSHIBA_DMID &&
	    intf->ddbl1_product_id == TOSHIBA_ES2_BRIDGE_DPID) {
		intf->quirks |= GB_INTERFACE_QUIRK_NO_GMP_IDS;
		intf->quirks |= GB_INTERFACE_QUIRK_NO_INIT_STATUS;
	}

	ret = gb_interface_read_ara_dme(intf);
	if (ret)
		return ret;

	intf->dme_read = true;

	return 0;
}

static int gb_interface_route_create(struct gb_interface *intf)
{
	struct gb_svc *svc = intf->hd->svc;
	u8 intf_id = intf->interface_id;
	u8 device_id;
	int ret;

	/* Allocate an interface device id. */
	ret = ida_simple_get(&svc->device_id_map,
			     GB_SVC_DEVICE_ID_MIN, GB_SVC_DEVICE_ID_MAX + 1,
			     GFP_KERNEL);
	if (ret < 0) {