pciehp_ctrl.c

audio driver for hotplug pci on linux 2.6.27

/*
 * PCI Express Hot Plug Controller Driver
 *
 * Copyright (C) 1995,2001 Compaq Computer Corporation
 * Copyright (C) 2001 Greg Kroah-Hartman ([e-mail])
 * Copyright (C) 2001 IBM Corp.
 * Copyright (C) 2003-2004 Intel Corporation
 *
 * All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or (at
 * your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 * NON INFRINGEMENT.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * Send feedback to <[e-mail]>, <[e-mail]>
 *
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/smp_lock.h>
#include <linux/pci.h>
#include <linux/workqueue.h>
#include "../pci.h"
#include "pciehp.h"

static void interrupt_event_handler(struct work_struct *work);

static int queue_interrupt_event(struct slot *p_slot, u32 event_type)
{
	struct event_info *info;

	info = kmalloc(sizeof(*info), GFP_ATOMIC);
	if (!info)
		return -ENOMEM;

	info->event_type = event_type;
	info->p_slot = p_slot;
	INIT_WORK(&info->work, interrupt_event_handler);

	schedule_work(&info->work);

	return 0;
}

u8 pciehp_handle_attention_button(struct slot *p_slot)
{
	u32 event_type;

	/* Attention Button Change */
	dbg("pciehp:  Attention button interrupt received.\n");

	/*
	 *  Button pressed - See if need to TAKE ACTION!!!
	 */
	info("Button pressed on Slot(%s)\n", slot_name(p_slot));
	event_type = INT_BUTTON_PRESS;

	queue_interrupt_event(p_slot, event_type);

	return 0;
}

u8 pciehp_handle_switch_change(struct slot *p_slot)
{
	u8 getstatus;
	u32 event_type;

	/* Switch Change */
	dbg("pciehp:  Switch interrupt received.\n");

	p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
	if (getstatus) {
		/*
		 * Switch opened
		 */
		info("Latch open on Slot(%s)\n", slot_name(p_slot));
		event_type = INT_SWITCH_OPEN;
	} else {
		/*
		 *  Switch closed
		 */
		info("Latch close on Slot(%s)\n", slot_name(p_slot));
		event_type = INT_SWITCH_CLOSE;
	}

	queue_interrupt_event(p_slot, event_type);

	return 1;
}

u8 pciehp_handle_presence_change(struct slot *p_slot)
{
	u32 event_type;
	u8 presence_save;

	/* Presence Change */
	dbg("pciehp:  Presence/Notify input change.\n");

	/* Switch is open, assume a presence change
	 * Save the presence state
	 */
	p_slot->hpc_ops->get_adapter_status(p_slot, &presence_save);
	if (presence_save) {
		/*
		 * Card Present
		 */
		info("Card present on Slot(%s)\n", slot_name(p_slot));
		event_type = INT_PRESENCE_ON;
	} else {
		/*
		 * Not Present
		 */
		info("Card not present on Slot(%s)\n", slot_name(p_slot));
		event_type = INT_PRESENCE_OFF;
	}

	queue_interrupt_event(p_slot, event_type);

	return 1;
}

u8 pciehp_handle_power_fault(struct slot *p_slot)
{
	u32 event_type;

	/* power fault */
	dbg("pciehp:  Power fault interrupt received.\n");

	if ( !(p_slot->hpc_ops->query_power_fault(p_slot))) {
		/*
		 * power fault Cleared
		 */
		info("Power fault cleared on Slot(%s)\n", slot_name(p_slot));
		event_type = INT_POWER_FAULT_CLEAR;
	} else {
		/*
		 *   power fault
		 */
		info("Power fault on Slot(%s)\n", slot_name(p_slot));
		event_type = INT_POWER_FAULT;
		info("power fault bit %x set\n", 0);
	}

	queue_interrupt_event(p_slot, event_type);

	return 1;
}

/* The following routines constitute the bulk of the
   hotplug controller logic
 */

static void set_slot_off(struct controller *ctrl, struct slot * pslot)
{
	/* turn off slot, turn on Amber LED, turn off Green LED if supported*/
	if (POWER_CTRL(ctrl)) {
		if (pslot->hpc_ops->power_off_slot(pslot)) {
			err("%s: Issue of Slot Power Off command failed\n",
			    __func__);
			return;
		}
	}

	/*
	 * After turning power off, we must wait for at least 1 second
	 * before taking any action that relies on power having been
	 * removed from the slot/adapter.
	 */
	msleep(1000);

	if (PWR_LED(ctrl))
		pslot->hpc_ops->green_led_off(pslot);

	if (ATTN_LED(ctrl)) {
		if (pslot->hpc_ops->set_attention_status(pslot, 1)) {
			err("%s: Issue of Set Attention Led command failed\n",
			    __func__);
			return;
		}
	}
}

/**
 * board_added - Called after a board has been added to the system.
 * @p_slot: &slot where board is added
 *
 * Turns power on for the board.
 * Configures board.
 */
static int board_added(struct slot *p_slot)
{
	int retval = 0;
	struct controller *ctrl = p_slot->ctrl;

	dbg("%s: slot device, slot offset, hp slot = %d, %d ,%d\n",
			__func__, p_slot->device,
			ctrl->slot_device_offset, p_slot->hp_slot);

	if (POWER_CTRL(ctrl)) {
		/* Power on slot */
		retval = p_slot->hpc_ops->power_on_slot(p_slot);
		if (retval)
			return retval;
	}

	if (PWR_LED(ctrl))
		p_slot->hpc_ops->green_led_blink(p_slot);

	/* Wait for ~1 second */
	msleep(1000);

	/* Check link training status */
	retval = p_slot->hpc_ops->check_lnk_status(ctrl);
	if (retval) {
		err("%s: Failed to check link status\n", __func__);
		set_slot_off(ctrl, p_slot);
		return retval;
	}

	/* Check for a power fault */
	if (p_slot->hpc_ops->query_power_fault(p_slot)) {
		dbg("%s: power fault detected\n", __func__);
		retval = POWER_FAILURE;
		goto err_exit;
	}

	retval = pciehp_configure_device(p_slot);
	if (retval) {
		err("Cannot add device 0x%x:%x\n", p_slot->bus,
		    p_slot->device);
		goto err_exit;
	}

	/*
	 * Some PCI Express root ports require fixup after hot-plug operation.
	 */
	if (pcie_mch_quirk)
		pci_fixup_device(pci_fixup_final, ctrl->pci_dev);
	if (PWR_LED(ctrl))
  		p_slot->hpc_ops->green_led_on(p_slot);

	return 0;

err_exit:
	set_slot_off(ctrl, p_slot);
	return retval;
}

/**
 * remove_board - Turns off slot and LEDs
 * @p_slot: slot where board is being removed
 */
static int remove_board(struct slot *p_slot)
{
	int retval = 0;
	struct controller *ctrl = p_slot->ctrl;

	retval = pciehp_unconfigure_device(p_slot);
	if (retval)
		return retval;

	dbg("In %s, hp_slot = %d\n", __func__, p_slot->hp_slot);

	if (POWER_CTRL(ctrl)) {
		/* power off slot */
		retval = p_slot->hpc_ops->power_off_slot(p_slot);
		if (retval) {
			err("%s: Issue of Slot Disable command failed\n",
			    __func__);
			return retval;
		}
	}

	/*
	 * After turning power off, we must wait for at least 1 second
	 * before taking any action that relies on power having been
	 * removed from the slot/adapter.
	 */
	msleep(1000);

	if (PWR_LED(ctrl))
		/* turn off Green LED */
		p_slot->hpc_ops->green_led_off(p_slot);

	return 0;
}

struct power_work_info {
	struct slot *p_slot;
	struct work_struct work;
};

/**
 * pciehp_power_thread - handle pushbutton events
 * @work: &struct work_struct describing work to be done
 *
 * Scheduled procedure to handle blocking stuff for the pushbuttons.
 * Handles all pending events and exits.
 */
static void pciehp_power_thread(struct work_struct *work)
{
	struct power_work_info *info =
		container_of(work, struct power_work_info, work);
	struct slot *p_slot = info->p_slot;

	mutex_lock(&p_slot->lock);
	switch (p_slot->state) {
	case POWEROFF_STATE:
		mutex_unlock(&p_slot->lock);
		dbg("%s: disabling bus:device(%x:%x)\n",
		    __func__, p_slot->bus, p_slot->device);
		pciehp_disable_slot(p_slot);
		mutex_lock(&p_slot->lock);
		p_slot->state = STATIC_STATE;
		break;
	case POWERON_STATE:
		mutex_unlock(&p_slot->lock);
		if (pciehp_enable_slot(p_slot) &&
		    PWR_LED(p_slot->ctrl))
			p_slot->hpc_ops->green_led_off(p_slot);
		mutex_lock(&p_slot->lock);
		p_slot->state = STATIC_STATE;
		break;
	default:
		break;
	}
	mutex_unlock(&p_slot->lock);