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authorDavid S. Miller <davem@davemloft.net>2008-08-29 22:34:14 -0700
committerDavid S. Miller <davem@davemloft.net>2008-08-29 22:34:14 -0700
commite21e245bcd9d5244735799387d14421789b20557 (patch)
treed8bfe0be5ac850764203b440566ef279cd47c7b5 /drivers
parent6b8c90f24e24505f97efaef1a46572d6b45929b9 (diff)
bbc_i2c: Convert to pure OF driver.
This thing was a mess, who wrote this junk? :) Luckily we'll soon have nice generic I2C layer drivers for this PCF based I2C stuff on sparc64. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/sbus/char/bbc_envctrl.c121
-rw-r--r--drivers/sbus/char/bbc_i2c.c267
-rw-r--r--drivers/sbus/char/bbc_i2c.h75
3 files changed, 214 insertions, 249 deletions
diff --git a/drivers/sbus/char/bbc_envctrl.c b/drivers/sbus/char/bbc_envctrl.c
index 0bde26989a23..abe4d50de21d 100644
--- a/drivers/sbus/char/bbc_envctrl.c
+++ b/drivers/sbus/char/bbc_envctrl.c
@@ -1,15 +1,15 @@
-/* $Id: bbc_envctrl.c,v 1.4 2001/04/06 16:48:08 davem Exp $
- * bbc_envctrl.c: UltraSPARC-III environment control driver.
+/* bbc_envctrl.c: UltraSPARC-III environment control driver.
*
- * Copyright (C) 2001 David S. Miller (davem@redhat.com)
+ * Copyright (C) 2001, 2008 David S. Miller (davem@davemloft.net)
*/
#include <linux/kthread.h>
#include <linux/delay.h>
#include <linux/kmod.h>
#include <linux/reboot.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
#include <asm/oplib.h>
-#include <asm/ebus.h>
#include "bbc_i2c.h"
#include "max1617.h"
@@ -75,43 +75,8 @@ static struct temp_limits amb_temp_limits[2] = {
{ 65, 55, 40, 5, -5, -10 },
};
-enum fan_action { FAN_SLOWER, FAN_SAME, FAN_FASTER, FAN_FULLBLAST, FAN_STATE_MAX };
-
-struct bbc_cpu_temperature {
- struct bbc_cpu_temperature *next;
-
- struct bbc_i2c_client *client;
- int index;
-
- /* Current readings, and history. */
- s8 curr_cpu_temp;
- s8 curr_amb_temp;
- s8 prev_cpu_temp;
- s8 prev_amb_temp;
- s8 avg_cpu_temp;
- s8 avg_amb_temp;
-
- int sample_tick;
-
- enum fan_action fan_todo[2];
-#define FAN_AMBIENT 0
-#define FAN_CPU 1
-};
-
-struct bbc_cpu_temperature *all_bbc_temps;
-
-struct bbc_fan_control {
- struct bbc_fan_control *next;
-
- struct bbc_i2c_client *client;
- int index;
-
- int psupply_fan_on;
- int cpu_fan_speed;
- int system_fan_speed;
-};
-
-struct bbc_fan_control *all_bbc_fans;
+static LIST_HEAD(all_temps);
+static LIST_HEAD(all_fans);
#define CPU_FAN_REG 0xf0
#define SYS_FAN_REG 0xf2
@@ -330,7 +295,7 @@ static enum fan_action prioritize_fan_action(int which_fan)
* recommend we do, and perform that action on all the
* fans.
*/
- for (tp = all_bbc_temps; tp; tp = tp->next) {
+ list_for_each_entry(tp, &all_temps, glob_list) {
if (tp->fan_todo[which_fan] == FAN_FULLBLAST) {
decision = FAN_FULLBLAST;
break;
@@ -439,7 +404,7 @@ static void fans_full_blast(void)
/* Since we will not be monitoring things anymore, put
* the fans on full blast.
*/
- for (fp = all_bbc_fans; fp; fp = fp->next) {
+ list_for_each_entry(fp, &all_fans, glob_list) {
fp->cpu_fan_speed = FAN_SPEED_MAX;
fp->system_fan_speed = FAN_SPEED_MAX;
fp->psupply_fan_on = 1;
@@ -463,11 +428,11 @@ static int kenvctrld(void *__unused)
if (kthread_should_stop())
break;
- for (tp = all_bbc_temps; tp; tp = tp->next) {
+ list_for_each_entry(tp, &all_temps, glob_list) {
get_current_temps(tp);
analyze_temps(tp, &last_warning_jiffies);
}
- for (fp = all_bbc_fans; fp; fp = fp->next)
+ list_for_each_entry(fp, &all_fans, glob_list)
maybe_new_fan_speeds(fp);
}
printk(KERN_INFO "bbc_envctrl: kenvctrld exiting...\n");
@@ -477,7 +442,8 @@ static int kenvctrld(void *__unused)
return 0;
}
-static void attach_one_temp(struct linux_ebus_child *echild, int temp_idx)
+static void attach_one_temp(struct bbc_i2c_bus *bp, struct of_device *op,
+ int temp_idx)
{
struct bbc_cpu_temperature *tp;
@@ -485,20 +451,17 @@ static void attach_one_temp(struct linux_ebus_child *echild, int temp_idx)
if (!tp)
return;
- tp->client = bbc_i2c_attach(echild);
+ tp->client = bbc_i2c_attach(op);
if (!tp->client) {
kfree(tp);
return;
}
+
tp->index = temp_idx;
- {
- struct bbc_cpu_temperature **tpp = &all_bbc_temps;
- while (*tpp)
- tpp = &((*tpp)->next);
- tp->next = NULL;
- *tpp = tp;
- }
+
+ list_add(&tp->glob_list, &all_temps);
+ list_add(&tp->bp_list, &bp->temps);
/* Tell it to convert once every 5 seconds, clear all cfg
* bits.
@@ -524,7 +487,8 @@ static void attach_one_temp(struct linux_ebus_child *echild, int temp_idx)
tp->fan_todo[FAN_CPU] = FAN_SAME;
}
-static void attach_one_fan(struct linux_ebus_child *echild, int fan_idx)
+static void attach_one_fan(struct bbc_i2c_bus *bp, struct of_device *op,
+ int fan_idx)
{
struct bbc_fan_control *fp;
@@ -532,7 +496,7 @@ static void attach_one_fan(struct linux_ebus_child *echild, int fan_idx)
if (!fp)
return;
- fp->client = bbc_i2c_attach(echild);
+ fp->client = bbc_i2c_attach(op);
if (!fp->client) {
kfree(fp);
return;
@@ -540,13 +504,8 @@ static void attach_one_fan(struct linux_ebus_child *echild, int fan_idx)
fp->index = fan_idx;
- {
- struct bbc_fan_control **fpp = &all_bbc_fans;
- while (*fpp)
- fpp = &((*fpp)->next);
- fp->next = NULL;
- *fpp = fp;
- }
+ list_add(&fp->glob_list, &all_fans);
+ list_add(&fp->bp_list, &bp->fans);
/* The i2c device controlling the fans is write-only.
* So the only way to keep track of the current power
@@ -563,18 +522,18 @@ static void attach_one_fan(struct linux_ebus_child *echild, int fan_idx)
set_fan_speeds(fp);
}
-int bbc_envctrl_init(void)
+int bbc_envctrl_init(struct bbc_i2c_bus *bp)
{
- struct linux_ebus_child *echild;
+ struct of_device *op;
int temp_index = 0;
int fan_index = 0;
int devidx = 0;
- while ((echild = bbc_i2c_getdev(devidx++)) != NULL) {
- if (!strcmp(echild->prom_node->name, "temperature"))
- attach_one_temp(echild, temp_index++);
- if (!strcmp(echild->prom_node->name, "fan-control"))
- attach_one_fan(echild, fan_index++);
+ while ((op = bbc_i2c_getdev(devidx++)) != NULL) {
+ if (!strcmp(op->node->name, "temperature"))
+ attach_one_temp(bp, op, temp_index++);
+ if (!strcmp(op->node->name, "fan-control"))
+ attach_one_fan(bp, op, fan_index++);
}
if (temp_index != 0 && fan_index != 0) {
kenvctrld_task = kthread_run(kenvctrld, NULL, "kenvctrld");
@@ -597,26 +556,22 @@ static void destroy_one_fan(struct bbc_fan_control *fp)
kfree(fp);
}
-void bbc_envctrl_cleanup(void)
+void bbc_envctrl_cleanup(struct bbc_i2c_bus *bp)
{
- struct bbc_cpu_temperature *tp;
- struct bbc_fan_control *fp;
+ struct bbc_cpu_temperature *tp, *tpos;
+ struct bbc_fan_control *fp, *fpos;
kthread_stop(kenvctrld_task);
- tp = all_bbc_temps;
- while (tp != NULL) {
- struct bbc_cpu_temperature *next = tp->next;
+ list_for_each_entry_safe(tp, tpos, &bp->temps, bp_list) {
+ list_del(&tp->bp_list);
+ list_del(&tp->glob_list);
destroy_one_temp(tp);
- tp = next;
}
- all_bbc_temps = NULL;
- fp = all_bbc_fans;
- while (fp != NULL) {
- struct bbc_fan_control *next = fp->next;
+ list_for_each_entry_safe(fp, fpos, &bp->fans, bp_list) {
+ list_del(&fp->bp_list);
+ list_del(&fp->glob_list);
destroy_one_fan(fp);
- fp = next;
}
- all_bbc_fans = NULL;
}
diff --git a/drivers/sbus/char/bbc_i2c.c b/drivers/sbus/char/bbc_i2c.c
index ac8ef2ce07fb..af7f4af6c5fb 100644
--- a/drivers/sbus/char/bbc_i2c.c
+++ b/drivers/sbus/char/bbc_i2c.c
@@ -1,8 +1,7 @@
-/* $Id: bbc_i2c.c,v 1.2 2001/04/02 09:59:08 davem Exp $
- * bbc_i2c.c: I2C low-level driver for BBC device on UltraSPARC-III
+/* bbc_i2c.c: I2C low-level driver for BBC device on UltraSPARC-III
* platforms.
*
- * Copyright (C) 2001 David S. Miller (davem@redhat.com)
+ * Copyright (C) 2001, 2008 David S. Miller (davem@davemloft.net)
*/
#include <linux/module.h>
@@ -14,9 +13,8 @@
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/interrupt.h>
-#include <asm/oplib.h>
-#include <asm/ebus.h>
-#include <asm/spitfire.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
#include <asm/bbc.h>
#include <asm/io.h>
@@ -53,54 +51,12 @@
* The second controller also connects to the smartcard reader, if present.
*/
-#define NUM_CHILDREN 8
-struct bbc_i2c_bus {
- struct bbc_i2c_bus *next;
- int index;
- spinlock_t lock;
- void __iomem *i2c_bussel_reg;
- void __iomem *i2c_control_regs;
- unsigned char own, clock;
-
- wait_queue_head_t wq;
- volatile int waiting;
-
- struct linux_ebus_device *bus_edev;
- struct {
- struct linux_ebus_child *device;
- int client_claimed;
- } devs[NUM_CHILDREN];
-};
-
-static struct bbc_i2c_bus *all_bbc_i2c;
-
-struct bbc_i2c_client {
- struct bbc_i2c_bus *bp;
- struct linux_ebus_child *echild;
- int bus;
- int address;
-};
-
-static int find_device(struct bbc_i2c_bus *bp, struct linux_ebus_child *echild)
+static void set_device_claimage(struct bbc_i2c_bus *bp, struct of_device *op, int val)
{
int i;
for (i = 0; i < NUM_CHILDREN; i++) {
- if (bp->devs[i].device == echild) {
- if (bp->devs[i].client_claimed)
- return 0;
- return 1;
- }
- }
- return 0;
-}
-
-static void set_device_claimage(struct bbc_i2c_bus *bp, struct linux_ebus_child *echild, int val)
-{
- int i;
-
- for (i = 0; i < NUM_CHILDREN; i++) {
- if (bp->devs[i].device == echild) {
+ if (bp->devs[i].device == op) {
bp->devs[i].client_claimed = val;
return;
}
@@ -110,61 +66,47 @@ static void set_device_claimage(struct bbc_i2c_bus *bp, struct linux_ebus_child
#define claim_device(BP,ECHILD) set_device_claimage(BP,ECHILD,1)
#define release_device(BP,ECHILD) set_device_claimage(BP,ECHILD,0)
-static struct bbc_i2c_bus *find_bus_for_device(struct linux_ebus_child *echild)
+struct of_device *bbc_i2c_getdev(struct bbc_i2c_bus *bp, int index)
{
- struct bbc_i2c_bus *bp = all_bbc_i2c;
+ struct of_device *op = NULL;
+ int curidx = 0, i;
- while (bp != NULL) {
- if (find_device(bp, echild) != 0)
+ for (i = 0; i < NUM_CHILDREN; i++) {
+ if (!(op = bp->devs[i].device))
break;
- bp = bp->next;
+ if (curidx == index)
+ goto out;
+ op = NULL;
+ curidx++;
}
- return bp;
-}
-
-struct linux_ebus_child *bbc_i2c_getdev(int index)
-{
- struct bbc_i2c_bus *bp = all_bbc_i2c;
- struct linux_ebus_child *echild = NULL;
- int curidx = 0;
-
- while (bp != NULL) {
- struct bbc_i2c_bus *next = bp->next;
- int i;
-
- for (i = 0; i < NUM_CHILDREN; i++) {
- if (!(echild = bp->devs[i].device))
- break;
- if (curidx == index)
- goto out;
- echild = NULL;
- curidx++;
- }
- bp = next;
- }
out:
if (curidx == index)
- return echild;
+ return op;
return NULL;
}
-struct bbc_i2c_client *bbc_i2c_attach(struct linux_ebus_child *echild)
+struct bbc_i2c_client *bbc_i2c_attach(struct bbc_i2c_bus *bp, struct of_device *op)
{
- struct bbc_i2c_bus *bp = find_bus_for_device(echild);
struct bbc_i2c_client *client;
+ const u32 *reg;
- if (!bp)
- return NULL;
client = kzalloc(sizeof(*client), GFP_KERNEL);
if (!client)
return NULL;
client->bp = bp;
- client->echild = echild;
- client->bus = echild->resource[0].start;
- client->address = echild->resource[1].start;
+ client->op = op;
+
+ reg = of_get_property(op->node, "reg", NULL);
+ if (!reg) {
+ kfree(client);
+ return NULL;
+ }
- claim_device(bp, echild);
+ client->bus = reg[0];
+ client->address = reg[1];
+
+ claim_device(bp, op);
return client;
}
@@ -172,9 +114,9 @@ struct bbc_i2c_client *bbc_i2c_attach(struct linux_ebus_child *echild)
void bbc_i2c_detach(struct bbc_i2c_client *client)
{
struct bbc_i2c_bus *bp = client->bp;
- struct linux_ebus_child *echild = client->echild;
+ struct of_device *op = client->op;
- release_device(bp, echild);
+ release_device(bp, op);
kfree(client);
}
@@ -355,44 +297,43 @@ static void __init reset_one_i2c(struct bbc_i2c_bus *bp)
writeb(I2C_PCF_IDLE, bp->i2c_control_regs + 0x0);
}
-static int __init attach_one_i2c(struct linux_ebus_device *edev, int index)
+static struct bbc_i2c_bus * __init attach_one_i2c(struct of_device *op, int index)
{
struct bbc_i2c_bus *bp;
- struct linux_ebus_child *echild;
+ struct device_node *dp;
int entry;
bp = kzalloc(sizeof(*bp), GFP_KERNEL);
if (!bp)
- return -ENOMEM;
+ return NULL;
- bp->i2c_control_regs = ioremap(edev->resource[0].start, 0x2);
+ bp->i2c_control_regs = of_ioremap(&op->resource[0], 0, 0x2, "bbc_i2c_regs");
if (!bp->i2c_control_regs)
goto fail;
- if (edev->num_addrs == 2) {
- bp->i2c_bussel_reg = ioremap(edev->resource[1].start, 0x1);
- if (!bp->i2c_bussel_reg)
- goto fail;
- }
+ bp->i2c_bussel_reg = of_ioremap(&op->resource[1], 0, 0x1, "bbc_i2c_bussel");
+ if (!bp->i2c_bussel_reg)
+ goto fail;
bp->waiting = 0;
init_waitqueue_head(&bp->wq);
- if (request_irq(edev->irqs[0], bbc_i2c_interrupt,
+ if (request_irq(op->irqs[0], bbc_i2c_interrupt,
IRQF_SHARED, "bbc_i2c", bp))
goto fail;
bp->index = index;
- bp->bus_edev = edev;
+ bp->op = op;
spin_lock_init(&bp->lock);
- bp->next = all_bbc_i2c;
- all_bbc_i2c = bp;
entry = 0;
- for (echild = edev->children;
- echild && entry < 8;
- echild = echild->next, entry++) {
- bp->devs[entry].device = echild;
+ for (dp = op->node->child;
+ dp && entry < 8;
+ dp = dp->sibling, entry++) {
+ struct of_device *child_op;
+
+ child_op = of_find_device_by_node(dp);
+ bp->devs[entry].device = child_op;
bp->devs[entry].client_claimed = 0;
}
@@ -406,86 +347,90 @@ static int __init attach_one_i2c(struct linux_ebus_device *edev, int index)
reset_one_i2c(bp);
- return 0;
+ return bp;
fail:
if (bp->i2c_bussel_reg)
- iounmap(bp->i2c_bussel_reg);
+ of_iounmap(&op->resource[1], bp->i2c_bussel_reg, 1);
if (bp->i2c_control_regs)
- iounmap(bp->i2c_control_regs);
+ of_iounmap(&op->resource[0], bp->i2c_control_regs, 2);
kfree(bp);
- return -EINVAL;
-}
-
-static int __init bbc_present(void)
-{
- struct linux_ebus *ebus = NULL;
- struct linux_ebus_device *edev = NULL;
-
- for_each_ebus(ebus) {
- for_each_ebusdev(edev, ebus) {
- if (!strcmp(edev->prom_node->name, "bbc"))
- return 1;
- }
- }
- return 0;
+ return NULL;
}
-extern int bbc_envctrl_init(void);
-extern void bbc_envctrl_cleanup(void);
-static void bbc_i2c_cleanup(void);
+extern int bbc_envctrl_init(struct bbc_i2c_bus *bp);
+extern void bbc_envctrl_cleanup(struct bbc_i2c_bus *bp);
-static int __init bbc_i2c_init(void)
+static int __devinit bbc_i2c_probe(struct of_device *op,
+ const struct of_device_id *match)
{
- struct linux_ebus *ebus = NULL;
- struct linux_ebus_device *edev = NULL;
+ struct bbc_i2c_bus *bp;
int err, index = 0;
- if ((tlb_type != cheetah && tlb_type != cheetah_plus) ||
- !bbc_present())
- return -ENODEV;
+ bp = attach_one_i2c(op, index);
+ if (!bp)
+ return -EINVAL;
- for_each_ebus(ebus) {
- for_each_ebusdev(edev, ebus) {
- if (!strcmp(edev->prom_node->name, "i2c")) {
- if (!attach_one_i2c(edev, index))
- index++;
- }
- }
+ err = bbc_envctrl_init(bp);
+ if (err) {
+ free_irq(op->irqs[0], bp);
+ if (bp->i2c_bussel_reg)
+ of_iounmap(&op->resource[0], bp->i2c_bussel_reg, 1);
+ if (bp->i2c_control_regs)
+ of_iounmap(&op->resource[1], bp->i2c_control_regs, 2);
+ kfree(bp);
+ } else {
+ dev_set_drvdata(&op->dev, bp);
}
- if (!index)
- return -ENODEV;
-
- err = bbc_envctrl_init();
- if (err)
- bbc_i2c_cleanup();
return err;
}
-static void bbc_i2c_cleanup(void)
+static int __devexit bbc_i2c_remove(struct of_device *op)
{
- struct bbc_i2c_bus *bp = all_bbc_i2c;
+ struct bbc_i2c_bus *bp = dev_get_drvdata(&op->dev);
+
+ bbc_envctrl_cleanup(bp);
+
+ free_irq(op->irqs[0], bp);
- bbc_envctrl_cleanup();
+ if (bp->i2c_bussel_reg)
+ of_iounmap(&op->resource[0], bp->i2c_bussel_reg, 1);
+ if (bp->i2c_control_regs)
+ of_iounmap(&op->resource[1], bp->i2c_control_regs, 2);
- while (bp != NULL) {
- struct bbc_i2c_bus *next = bp->next;
+ kfree(bp);
- free_irq(bp->bus_edev->irqs[0], bp);
+ return 0;
+}
- if (bp->i2c_bussel_reg)
- iounmap(bp->i2c_bussel_reg);
- if (bp->i2c_control_regs)
- iounmap(bp->i2c_control_regs);
+static struct of_device_id bbc_i2c_match[] = {
+ {
+ .name = "i2c",
+ .compatible = "SUNW,bbc-i2c",
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, bbc_i2c_match);
- kfree(bp);
+static struct of_platform_driver bbc_i2c_driver = {
+ .name = "bbc_i2c",
+ .match_table = bbc_i2c_match,
+ .probe = bbc_i2c_probe,
+ .remove = __devexit_p(bbc_i2c_remove),
+};
- bp = next;
- }
- all_bbc_i2c = NULL;
+static int __init bbc_i2c_init(void)
+{
+ return of_register_driver(&bbc_i2c_driver, &of_bus_type);
+}
+
+static void __exit bbc_i2c_exit(void)
+{
+ of_unregister_driver(&bbc_i2c_driver);
}
module_init(bbc_i2c_init);
-module_exit(bbc_i2c_cleanup);
+module_exit(bbc_i2c_exit);
+
MODULE_LICENSE("GPL");
diff --git a/drivers/sbus/char/bbc_i2c.h b/drivers/sbus/char/bbc_i2c.h
index fb01bd17704b..83c4811b7b5e 100644
--- a/drivers/sbus/char/bbc_i2c.h
+++ b/drivers/sbus/char/bbc_i2c.h
@@ -1,14 +1,79 @@
-/* $Id: bbc_i2c.h,v 1.2 2001/04/02 09:59:25 davem Exp $ */
#ifndef _BBC_I2C_H
#define _BBC_I2C_H
-#include <asm/ebus.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/list.h>
-struct bbc_i2c_client;
+struct bbc_i2c_client {
+ struct bbc_i2c_bus *bp;
+ struct of_device *op;
+ int bus;
+ int address;
+};
+
+enum fan_action { FAN_SLOWER, FAN_SAME, FAN_FASTER, FAN_FULLBLAST, FAN_STATE_MAX };
+
+struct bbc_cpu_temperature {
+ struct list_head bp_list;
+ struct list_head glob_list;
+
+ struct bbc_i2c_client *client;
+ int index;
+
+ /* Current readings, and history. */
+ s8 curr_cpu_temp;
+ s8 curr_amb_temp;
+ s8 prev_cpu_temp;
+ s8 prev_amb_temp;
+ s8 avg_cpu_temp;
+ s8 avg_amb_temp;
+
+ int sample_tick;
+
+ enum fan_action fan_todo[2];
+#define FAN_AMBIENT 0
+#define FAN_CPU 1
+};
+
+struct bbc_fan_control {
+ struct list_head bp_list;
+ struct list_head glob_list;
+
+ struct bbc_i2c_client *client;
+ int index;
+
+ int psupply_fan_on;
+ int cpu_fan_speed;
+ int system_fan_speed;
+};
+
+#define NUM_CHILDREN 8
+
+struct bbc_i2c_bus {
+ struct bbc_i2c_bus *next;
+ int index;
+ spinlock_t lock;
+ void __iomem *i2c_bussel_reg;
+ void __iomem *i2c_control_regs;
+ unsigned char own, clock;
+
+ wait_queue_head_t wq;
+ volatile int waiting;
+
+ struct list_head temps;
+ struct list_head fans;
+
+ struct of_device *op;
+ struct {
+ struct of_device *device;
+ int client_claimed;
+ } devs[NUM_CHILDREN];
+};
/* Probing and attachment. */
-extern struct linux_ebus_child *bbc_i2c_getdev(int);
-extern struct bbc_i2c_client *bbc_i2c_attach(struct linux_ebus_child *);
+extern struct of_device *bbc_i2c_getdev(struct bbc_i2c_bus *, int);
+extern struct bbc_i2c_client *bbc_i2c_attach(struct bbc_i2c_bus *bp, struct of_device *);
extern void bbc_i2c_detach(struct bbc_i2c_client *);
/* Register read/write. NOTE: Blocking! */