envctrl.c

linux-2.6.15.6

 * Return: None.
 */
static void envctrl_init_adc(struct i2c_child_t *pchild, int node)
{
	char chnls_desc[CHANNEL_DESC_SZ];
	int i = 0, len;
	char *pos = chnls_desc;

	/* Firmware describe channels into a stream separated by a '\0'. */
	len = prom_getproperty(node, "channels-description", chnls_desc,
			       CHANNEL_DESC_SZ);
	chnls_desc[CHANNEL_DESC_SZ - 1] = '\0';

	while (len > 0) {
		int l = strlen(pos) + 1;
		envctrl_set_mon(pchild, pos, i++);
		len -= l;
		pos += l;
	}

	/* Get optional properties. */
        len = prom_getproperty(node, "warning-temp", (char *)&warning_temperature,
			       sizeof(warning_temperature));
        len = prom_getproperty(node, "shutdown-temp", (char *)&shutdown_temperature,
			       sizeof(shutdown_temperature));
}

/* Function Description: Initialize child device monitoring fan status.
 * Return: None.
 */
static void envctrl_init_fanstat(struct i2c_child_t *pchild)
{
	int i;

	/* Go through all channels and set up the mask. */
	for (i = 0; i < pchild->total_chnls; i++)
		pchild->fan_mask |= chnls_mask[(pchild->chnl_array[i]).chnl_no];

	/* We only need to know if this child has fan status monitored.
	 * We don't care which channels since we have the mask already.
	 */
	pchild->mon_type[0] = ENVCTRL_FANSTAT_MON;
}

/* Function Description: Initialize child device for global addressing line.
 * Return: None.
 */
static void envctrl_init_globaladdr(struct i2c_child_t *pchild)
{
	int i;

	/* Voltage/PowerSupply monitoring is piggybacked 
	 * with Global Address on CompactPCI.  See comments
	 * within envctrl_i2c_globaladdr for bit assignments.
	 *
	 * The mask is created here by assigning mask bits to each
	 * bit position that represents PCF8584_VOLTAGE_TYPE data.
	 * Channel numbers are not consecutive within the globaladdr
	 * node (why?), so we use the actual counter value as chnls_mask
	 * index instead of the chnl_array[x].chnl_no value.
	 *
	 * NOTE: This loop could be replaced with a constant representing
	 * a mask of bits 5&6 (ENVCTRL_GLOBALADDR_PSTAT_MASK).
	 */
	for (i = 0; i < pchild->total_chnls; i++) {
		if (PCF8584_VOLTAGE_TYPE == pchild->chnl_array[i].type) {
			pchild->voltage_mask |= chnls_mask[i];
		}
	}

	/* We only need to know if this child has global addressing 
	 * line monitored.  We don't care which channels since we know 
	 * the mask already (ENVCTRL_GLOBALADDR_ADDR_MASK).
	 */
	pchild->mon_type[0] = ENVCTRL_GLOBALADDR_MON;
}

/* Initialize child device monitoring voltage status. */
static void envctrl_init_voltage_status(struct i2c_child_t *pchild)
{
	int i;

	/* Go through all channels and set up the mask. */
	for (i = 0; i < pchild->total_chnls; i++)
		pchild->voltage_mask |= chnls_mask[(pchild->chnl_array[i]).chnl_no];

	/* We only need to know if this child has voltage status monitored.
	 * We don't care which channels since we have the mask already.
	 */
	pchild->mon_type[0] = ENVCTRL_VOLTAGESTAT_MON;
}

/* Function Description: Initialize i2c child device.
 * Return: None.
 */
static void envctrl_init_i2c_child(struct linux_ebus_child *edev_child,
				   struct i2c_child_t *pchild)
{
	int node, len, i, tbls_size = 0;

	node = edev_child->prom_node;

	/* Get device address. */
	len = prom_getproperty(node, "reg",
			       (char *) &(pchild->addr),
			       sizeof(pchild->addr));

	/* Get tables property.  Read firmware temperature tables. */
	len = prom_getproperty(node, "translation",
			       (char *) pchild->tblprop_array,
			       (PCF8584_MAX_CHANNELS *
				sizeof(struct pcf8584_tblprop)));
	if (len > 0) {
                pchild->total_tbls = len / sizeof(struct pcf8584_tblprop);
		for (i = 0; i < pchild->total_tbls; i++) {
			if ((pchild->tblprop_array[i].size + pchild->tblprop_array[i].offset) > tbls_size) {
				tbls_size = pchild->tblprop_array[i].size + pchild->tblprop_array[i].offset;
			}
		}

                pchild->tables = kmalloc(tbls_size, GFP_KERNEL);
		if (pchild->tables == NULL){
			printk("envctrl: Failed to allocate table.\n");
			return;
		}
                len = prom_getproperty(node, "tables",
				       (char *) pchild->tables, tbls_size);
                if (len <= 0) {
			printk("envctrl: Failed to get table.\n");
			return;
		}
	}

	/* SPARCengine ASM Reference Manual (ref. SMI doc 805-7581-04)
	 * sections 2.5, 3.5, 4.5 state node 0x70 for CP1400/1500 is
	 * "For Factory Use Only."
	 *
	 * We ignore the node on these platforms by assigning the
	 * 'NULL' monitor type.
	 */
	if (ENVCTRL_CPCI_IGNORED_NODE == pchild->addr) {
		int len;
		char prop[56];

		len = prom_getproperty(prom_root_node, "name", prop, sizeof(prop));
		if (0 < len && (0 == strncmp(prop, "SUNW,UltraSPARC-IIi-cEngine", len)))
		{
			for (len = 0; len < PCF8584_MAX_CHANNELS; ++len) {
				pchild->mon_type[len] = ENVCTRL_NOMON;
			}
			return;
		}
	}

	/* Get the monitor channels. */
	len = prom_getproperty(node, "channels-in-use",
			       (char *) pchild->chnl_array,
			       (PCF8584_MAX_CHANNELS *
				sizeof(struct pcf8584_channel)));
	pchild->total_chnls = len / sizeof(struct pcf8584_channel);

	for (i = 0; i < pchild->total_chnls; i++) {
		switch (pchild->chnl_array[i].type) {
		case PCF8584_TEMP_TYPE:
			envctrl_init_adc(pchild, node);
			break;

		case PCF8584_GLOBALADDR_TYPE:
			envctrl_init_globaladdr(pchild);
			i = pchild->total_chnls;
			break;

		case PCF8584_FANSTAT_TYPE:
			envctrl_init_fanstat(pchild);
			i = pchild->total_chnls;
			break;

		case PCF8584_VOLTAGE_TYPE:
			if (pchild->i2ctype == I2C_ADC) {
				envctrl_init_adc(pchild,node);
			} else {
				envctrl_init_voltage_status(pchild);
			}
			i = pchild->total_chnls;
			break;

		default:
			break;
		};
	}
}

/* Function Description: Search the child device list for a device.
 * Return : The i2c child if found. NULL otherwise.
 */
static struct i2c_child_t *envctrl_get_i2c_child(unsigned char mon_type)
{
	int i, j;

	for (i = 0; i < ENVCTRL_MAX_CPU*2; i++) {
		for (j = 0; j < PCF8584_MAX_CHANNELS; j++) {
			if (i2c_childlist[i].mon_type[j] == mon_type) {
				return (struct i2c_child_t *)(&(i2c_childlist[i]));
			}
		}
	}
	return NULL;
}

static void envctrl_do_shutdown(void)
{
	static int inprog = 0;
	static char *envp[] = {	
		"HOME=/", "TERM=linux", "PATH=/sbin:/usr/sbin:/bin:/usr/bin", NULL };
	char *argv[] = { 
		"/sbin/shutdown", "-h", "now", NULL };	

	if (inprog != 0)
		return;

	inprog = 1;
	printk(KERN_CRIT "kenvctrld: WARNING: Shutting down the system now.\n");
	if (0 > execve("/sbin/shutdown", argv, envp)) {
		printk(KERN_CRIT "kenvctrld: WARNING: system shutdown failed!\n"); 
		inprog = 0;  /* unlikely to succeed, but we could try again */
	}
}

static struct task_struct *kenvctrld_task;

static int kenvctrld(void *__unused)
{
	int poll_interval;
	int whichcpu;
	char tempbuf[10];
	struct i2c_child_t *cputemp;

	if (NULL == (cputemp = envctrl_get_i2c_child(ENVCTRL_CPUTEMP_MON))) {
		printk(KERN_ERR 
		       "envctrl: kenvctrld unable to monitor CPU temp-- exiting\n");
		return -ENODEV;
	}

	poll_interval = 5000; /* TODO env_mon_interval */

	printk(KERN_INFO "envctrl: %s starting...\n", current->comm);
	for (;;) {
		msleep_interruptible(poll_interval);

		if (kthread_should_stop())
			break;
		
		for (whichcpu = 0; whichcpu < ENVCTRL_MAX_CPU; ++whichcpu) {
			if (0 < envctrl_read_cpu_info(whichcpu, cputemp,
						      ENVCTRL_CPUTEMP_MON,
						      tempbuf)) {
				if (tempbuf[0] >= shutdown_temperature) {
					printk(KERN_CRIT 
						"%s: WARNING: CPU%i temperature %i C meets or exceeds "\
						"shutdown threshold %i C\n", 
						current->comm, whichcpu, 
						tempbuf[0], shutdown_temperature);
					envctrl_do_shutdown();
				}
			}
		}
	}
	printk(KERN_INFO "envctrl: %s exiting...\n", current->comm);
	return 0;
}

static int __init envctrl_init(void)
{
	struct linux_ebus *ebus = NULL;
	struct linux_ebus_device *edev = NULL;
	struct linux_ebus_child *edev_child = NULL;
	int err, i = 0;

	for_each_ebus(ebus) {
		for_each_ebusdev(edev, ebus) {
			if (!strcmp(edev->prom_name, "bbc")) {
				/* If we find a boot-bus controller node,
				 * then this envctrl driver is not for us.
				 */
				return -ENODEV;
			}
		}
	}

	/* Traverse through ebus and ebus device list for i2c device and
	 * adc and gpio nodes.
	 */
	for_each_ebus(ebus) {
		for_each_ebusdev(edev, ebus) {
			if (!strcmp(edev->prom_name, "i2c")) {
				i2c = ioremap(edev->resource[0].start, 0x2);
				for_each_edevchild(edev, edev_child) {
					if (!strcmp("gpio", edev_child->prom_name)) {
						i2c_childlist[i].i2ctype = I2C_GPIO;
						envctrl_init_i2c_child(edev_child, &(i2c_childlist[i++]));
					}
					if (!strcmp("adc", edev_child->prom_name)) {
						i2c_childlist[i].i2ctype = I2C_ADC;
						envctrl_init_i2c_child(edev_child, &(i2c_childlist[i++]));
					}
				}
				goto done;
			}
		}
	}

done:
	if (!edev) {
		printk("envctrl: I2C device not found.\n");
		return -ENODEV;
	}

	/* Set device address. */
	writeb(CONTROL_PIN, i2c + PCF8584_CSR);
	writeb(PCF8584_ADDRESS, i2c + PCF8584_DATA);

	/* Set system clock and SCL frequencies. */ 
	writeb(CONTROL_PIN | CONTROL_ES1, i2c + PCF8584_CSR);
	writeb(CLK_4_43 | BUS_CLK_90, i2c + PCF8584_DATA);

	/* Enable serial interface. */
	writeb(CONTROL_PIN | CONTROL_ES0 | CONTROL_ACK, i2c + PCF8584_CSR);
	udelay(200);

	/* Register the device as a minor miscellaneous device. */
	err = misc_register(&envctrl_dev);
	if (err) {
		printk("envctrl: Unable to get misc minor %d\n",
		       envctrl_dev.minor);
		goto out_iounmap;
	}

	/* Note above traversal routine post-incremented 'i' to accommodate 
	 * a next child device, so we decrement before reverse-traversal of
	 * child devices.
	 */
	printk("envctrl: initialized ");
	for (--i; i >= 0; --i) {
		printk("[%s 0x%lx]%s", 
			(I2C_ADC == i2c_childlist[i].i2ctype) ? ("adc") : 
			((I2C_GPIO == i2c_childlist[i].i2ctype) ? ("gpio") : ("unknown")), 
			i2c_childlist[i].addr, (0 == i) ? ("\n") : (" "));
	}

	kenvctrld_task = kthread_run(kenvctrld, NULL, "kenvctrld");
	if (IS_ERR(kenvctrld_task)) {
		err = PTR_ERR(kenvctrld_task);
		goto out_deregister;
	}

	return 0;

out_deregister:
	misc_deregister(&envctrl_dev);
out_iounmap:
	iounmap(i2c);
	for (i = 0; i < ENVCTRL_MAX_CPU * 2; i++)
		kfree(i2c_childlist[i].tables);

	return err;
}

static void __exit envctrl_cleanup(void)
{
	int i;

	kthread_stop(kenvctrld_task);

	iounmap(i2c);
	misc_deregister(&envctrl_dev);

	for (i = 0; i < ENVCTRL_MAX_CPU * 2; i++)
		kfree(i2c_childlist[i].tables);
}

module_init(envctrl_init);
module_exit(envctrl_cleanup);
MODULE_LICENSE("GPL");