1 files changed, 418 insertions, 0 deletions
diff --git a/drivers/macintosh/windfarm_smu_sat.c b/drivers/macintosh/windfarm_smu_sat.c
new file mode 100644
index 0000000..3a32c59
--- /dev/null
+++ b/drivers/macintosh/windfarm_smu_sat.c
@@ -0,0 +1,418 @@
+/*
+ * Windfarm PowerMac thermal control.  SMU "satellite" controller sensors.
+ *
+ * Copyright (C) 2005 Paul Mackerras, IBM Corp. <paulus@samba.org>
+ *
+ * Released under the terms of the GNU GPL v2.
+ */
+
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/wait.h>
+#include <linux/i2c.h>
+#include <linux/i2c-dev.h>
+#include <asm/semaphore.h>
+#include <asm/prom.h>
+#include <asm/smu.h>
+#include <asm/pmac_low_i2c.h>
+
+#include "windfarm.h"
+
+#define VERSION "0.2"
+
+#define DEBUG
+
+#ifdef DEBUG
+#define DBG(args...)	printk(args)
+#else
+#define DBG(args...)	do { } while(0)
+#endif
+
+/* If the cache is older than 800ms we'll refetch it */
+#define MAX_AGE		msecs_to_jiffies(800)
+
+struct wf_sat {
+	int			nr;
+	atomic_t		refcnt;
+	struct semaphore	mutex;
+	unsigned long		last_read; /* jiffies when cache last updated */
+	u8			cache[16];
+	struct i2c_client	i2c;
+	struct device_node	*node;
+};
+
+static struct wf_sat *sats[2];
+
+struct wf_sat_sensor {
+	int		index;
+	int		index2;		/* used for power sensors */
+	int		shift;
+	struct wf_sat	*sat;
+	struct wf_sensor sens;
+};
+
+#define wf_to_sat(c)	container_of(c, struct wf_sat_sensor, sens)
+#define i2c_to_sat(c)	container_of(c, struct wf_sat, i2c)
+
+static int wf_sat_attach(struct i2c_adapter *adapter);
+static int wf_sat_detach(struct i2c_client *client);
+
+static struct i2c_driver wf_sat_driver = {
+	.driver = {
+		.name		= "wf_smu_sat",
+	},
+	.attach_adapter	= wf_sat_attach,
+	.detach_client	= wf_sat_detach,
+};
+
+/*
+ * XXX i2c_smbus_read_i2c_block_data doesn't pass the requested
+ * length down to the low-level driver, so we use this, which
+ * works well enough with the SMU i2c driver code...
+ */
+static int sat_read_block(struct i2c_client *client, u8 command,
+			  u8 *values, int len)
+{
+	union i2c_smbus_data data;
+	int err;
+
+	data.block[0] = len;
+	err = i2c_smbus_xfer(client->adapter, client->addr, client->flags,
+			     I2C_SMBUS_READ, command, I2C_SMBUS_I2C_BLOCK_DATA,
+			     &data);
+	if (!err)
+		memcpy(values, data.block, len);
+	return err;
+}
+
+struct smu_sdbp_header *smu_sat_get_sdb_partition(unsigned int sat_id, int id,
+						  unsigned int *size)
+{
+	struct wf_sat *sat;
+	int err;
+	unsigned int i, len;
+	u8 *buf;
+	u8 data[4];
+
+	/* TODO: Add the resulting partition to the device-tree */
+
+	if (sat_id > 1 || (sat = sats[sat_id]) == NULL)
+		return NULL;
+
+	err = i2c_smbus_write_word_data(&sat->i2c, 8, id << 8);
+	if (err) {
+		printk(KERN_ERR "smu_sat_get_sdb_part wr error %d\n", err);
+		return NULL;
+	}
+
+	len = i2c_smbus_read_word_data(&sat->i2c, 9);
+	if (len < 0) {
+		printk(KERN_ERR "smu_sat_get_sdb_part rd len error\n");
+		return NULL;
+	}
+	if (len == 0) {
+		printk(KERN_ERR "smu_sat_get_sdb_part no partition %x\n", id);
+		return NULL;
+	}
+
+	len = le16_to_cpu(len);
+	len = (len + 3) & ~3;
+	buf = kmalloc(len, GFP_KERNEL);
+	if (buf == NULL)
+		return NULL;
+
+	for (i = 0; i < len; i += 4) {
+		err = sat_read_block(&sat->i2c, 0xa, data, 4);
+		if (err) {
+			printk(KERN_ERR "smu_sat_get_sdb_part rd err %d\n",
+			       err);
+			goto fail;
+		}
+		buf[i] = data[1];
+		buf[i+1] = data[0];
+		buf[i+2] = data[3];
+		buf[i+3] = data[2];
+	}
+#ifdef DEBUG
+	DBG(KERN_DEBUG "sat %d partition %x:", sat_id, id);
+	for (i = 0; i < len; ++i)
+		DBG(" %x", buf[i]);
+	DBG("\n");
+#endif
+
+	if (size)
+		*size = len;
+	return (struct smu_sdbp_header *) buf;
+
+ fail:
+	kfree(buf);
+	return NULL;
+}
+
+/* refresh the cache */
+static int wf_sat_read_cache(struct wf_sat *sat)
+{
+	int err;
+
+	err = sat_read_block(&sat->i2c, 0x3f, sat->cache, 16);
+	if (err)
+		return err;
+	sat->last_read = jiffies;
+#ifdef LOTSA_DEBUG
+	{
+		int i;
+		DBG(KERN_DEBUG "wf_sat_get: data is");
+		for (i = 0; i < 16; ++i)
+			DBG(" %.2x", sat->cache[i]);
+		DBG("\n");
+	}
+#endif
+	return 0;
+}
+
+static int wf_sat_get(struct wf_sensor *sr, s32 *value)
+{
+	struct wf_sat_sensor *sens = wf_to_sat(sr);
+	struct wf_sat *sat = sens->sat;
+	int i, err;
+	s32 val;
+
+	if (sat->i2c.adapter == NULL)
+		return -ENODEV;
+
+	down(&sat->mutex);
+	if (time_after(jiffies, (sat->last_read + MAX_AGE))) {
+		err = wf_sat_read_cache(sat);
+		if (err)
+			goto fail;
+	}
+
+	i = sens->index * 2;
+	val = ((sat->cache[i] << 8) + sat->cache[i+1]) << sens->shift;
+	if (sens->index2 >= 0) {
+		i = sens->index2 * 2;
+		/* 4.12 * 8.8 -> 12.20; shift right 4 to get 16.16 */
+		val = (val * ((sat->cache[i] << 8) + sat->cache[i+1])) >> 4;
+	}
+
+	*value = val;
+	err = 0;
+
+ fail:
+	up(&sat->mutex);
+	return err;
+}
+
+static void wf_sat_release(struct wf_sensor *sr)
+{
+	struct wf_sat_sensor *sens = wf_to_sat(sr);
+	struct wf_sat *sat = sens->sat;
+
+	if (atomic_dec_and_test(&sat->refcnt)) {
+		if (sat->i2c.adapter) {
+			i2c_detach_client(&sat->i2c);
+			sat->i2c.adapter = NULL;
+		}
+		if (sat->nr >= 0)
+			sats[sat->nr] = NULL;
+		kfree(sat);
+	}
+	kfree(sens);
+}
+
+static struct wf_sensor_ops wf_sat_ops = {
+	.get_value	= wf_sat_get,
+	.release	= wf_sat_release,
+	.owner		= THIS_MODULE,
+};
+
+static void wf_sat_create(struct i2c_adapter *adapter, struct device_node *dev)
+{
+	struct wf_sat *sat;
+	struct wf_sat_sensor *sens;
+	u32 *reg;
+	char *loc, *type;
+	u8 addr, chip, core;
+	struct device_node *child;
+	int shift, cpu, index;
+	char *name;
+	int vsens[2], isens[2];
+
+	reg = (u32 *) get_property(dev, "reg", NULL);
+	if (reg == NULL)
+		return;
+	addr = *reg;
+	DBG(KERN_DEBUG "wf_sat: creating sat at address %x\n", addr);
+
+	sat = kzalloc(sizeof(struct wf_sat), GFP_KERNEL);
+	if (sat == NULL)
+		return;
+	sat->nr = -1;
+	sat->node = of_node_get(dev);
+	atomic_set(&sat->refcnt, 0);
+	init_MUTEX(&sat->mutex);
+	sat->i2c.addr = (addr >> 1) & 0x7f;
+	sat->i2c.adapter = adapter;
+	sat->i2c.driver = &wf_sat_driver;
+	strncpy(sat->i2c.name, "smu-sat", I2C_NAME_SIZE-1);
+
+	if (i2c_attach_client(&sat->i2c)) {
+		printk(KERN_ERR "windfarm: failed to attach smu-sat to i2c\n");
+		goto fail;
+	}
+
+	vsens[0] = vsens[1] = -1;
+	isens[0] = isens[1] = -1;
+	child = NULL;
+	while ((child = of_get_next_child(dev, child)) != NULL) {
+		reg = (u32 *) get_property(child, "reg", NULL);
+		type = get_property(child, "device_type", NULL);
+		loc = get_property(child, "location", NULL);
+		if (reg == NULL || loc == NULL)
+			continue;
+
+		/* the cooked sensors are between 0x30 and 0x37 */
+		if (*reg < 0x30 || *reg > 0x37)
+			continue;
+		index = *reg - 0x30;
+
+		/* expect location to be CPU [AB][01] ... */
+		if (strncmp(loc, "CPU ", 4) != 0)
+			continue;
+		chip = loc[4] - 'A';
+		core = loc[5] - '0';
+		if (chip > 1 || core > 1) {
+			printk(KERN_ERR "wf_sat_create: don't understand "
+			       "location %s for %s\n", loc, child->full_name);
+			continue;
+		}
+		cpu = 2 * chip + core;
+		if (sat->nr < 0)
+			sat->nr = chip;
+		else if (sat->nr != chip) {
+			printk(KERN_ERR "wf_sat_create: can't cope with "
+			       "multiple CPU chips on one SAT (%s)\n", loc);
+			continue;
+		}
+
+		if (strcmp(type, "voltage-sensor") == 0) {
+			name = "cpu-voltage";
+			shift = 4;
+			vsens[core] = index;
+		} else if (strcmp(type, "current-sensor") == 0) {
+			name = "cpu-current";
+			shift = 8;
+			isens[core] = index;
+		} else if (strcmp(type, "temp-sensor") == 0) {
+			name = "cpu-temp";
+			shift = 10;
+		} else
+			continue;	/* hmmm shouldn't happen */
+
+		/* the +16 is enough for "cpu-voltage-n" */
+		sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL);
+		if (sens == NULL) {
+			printk(KERN_ERR "wf_sat_create: couldn't create "
+			       "%s sensor %d (no memory)\n", name, cpu);
+			continue;
+		}
+		sens->index = index;
+		sens->index2 = -1;
+		sens->shift = shift;
+		sens->sat = sat;
+		atomic_inc(&sat->refcnt);
+		sens->sens.ops = &wf_sat_ops;
+		sens->sens.name = (char *) (sens + 1);
+		snprintf(sens->sens.name, 16, "%s-%d", name, cpu);
+
+		if (wf_register_sensor(&sens->sens)) {
+			atomic_dec(&sat->refcnt);
+			kfree(sens);
+		}
+	}
+
+	/* make the power sensors */
+	for (core = 0; core < 2; ++core) {
+		if (vsens[core] < 0 || isens[core] < 0)
+			continue;
+		cpu = 2 * sat->nr + core;
+		sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL);
+		if (sens == NULL) {
+			printk(KERN_ERR "wf_sat_create: couldn't create power "
+			       "sensor %d (no memory)\n", cpu);
+			continue;
+		}
+		sens->index = vsens[core];
+		sens->index2 = isens[core];
+		sens->shift = 0;
+		sens->sat = sat;
+		atomic_inc(&sat->refcnt);
+		sens->sens.ops = &wf_sat_ops;
+		sens->sens.name = (char *) (sens + 1);
+		snprintf(sens->sens.name, 16, "cpu-power-%d", cpu);
+
+		if (wf_register_sensor(&sens->sens)) {
+			atomic_dec(&sat->refcnt);
+			kfree(sens);
+		}
+	}
+
+	if (sat->nr >= 0)
+		sats[sat->nr] = sat;
+
+	return;
+
+ fail:
+	kfree(sat);
+}
+
+static int wf_sat_attach(struct i2c_adapter *adapter)
+{
+	struct device_node *busnode, *dev = NULL;
+	struct pmac_i2c_bus *bus;
+
+	bus = pmac_i2c_adapter_to_bus(adapter);
+	if (bus == NULL)
+		return -ENODEV;
+	busnode = pmac_i2c_get_bus_node(bus);
+
+	while ((dev = of_get_next_child(busnode, dev)) != NULL)
+		if (device_is_compatible(dev, "smu-sat"))
+			wf_sat_create(adapter, dev);
+	return 0;
+}
+
+static int wf_sat_detach(struct i2c_client *client)
+{
+	struct wf_sat *sat = i2c_to_sat(client);
+
+	/* XXX TODO */
+
+	sat->i2c.adapter = NULL;
+	return 0;
+}
+
+static int __init sat_sensors_init(void)
+{
+	int err;
+
+	err = i2c_add_driver(&wf_sat_driver);
+	if (err < 0)
+		return err;
+	return 0;
+}
+
+static void __exit sat_sensors_exit(void)
+{
+	i2c_del_driver(&wf_sat_driver);
+}
+
+module_init(sat_sensors_init);
+/*module_exit(sat_sensors_exit); Uncomment when cleanup is implemented */
+
+MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
+MODULE_DESCRIPTION("SMU satellite sensors for PowerMac thermal control");
+MODULE_LICENSE("GPL");