/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi>.
All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl>
SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and
- Jean Delvare <khali@linux-fr.org> */
+ Jean Delvare <khali@linux-fr.org>
+ Mux support by Rodolfo Giometti <giometti@enneenne.com> and
+ Michael Lawnick <michael.lawnick.ext@nsn.com> */
#include <linux/module.h>
#include <linux/kernel.h>
return 0;
}
+/* walk up mux tree */
+static int i2c_check_mux_parents(struct i2c_adapter *adapter, int addr)
+{
+ int result;
+
+ result = device_for_each_child(&adapter->dev, &addr,
+ __i2c_check_addr_busy);
+
+ if (!result && i2c_parent_is_i2c_adapter(adapter))
+ result = i2c_check_mux_parents(
+ to_i2c_adapter(adapter->dev.parent), addr);
+
+ return result;
+}
+
+/* recurse down mux tree */
+static int i2c_check_mux_children(struct device *dev, void *addrp)
+{
+ int result;
+
+ if (dev->type == &i2c_adapter_type)
+ result = device_for_each_child(dev, addrp,
+ i2c_check_mux_children);
+ else
+ result = __i2c_check_addr_busy(dev, addrp);
+
+ return result;
+}
+
static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr)
{
- return device_for_each_child(&adapter->dev, &addr,
- __i2c_check_addr_busy);
+ int result = 0;
+
+ if (i2c_parent_is_i2c_adapter(adapter))
+ result = i2c_check_mux_parents(
+ to_i2c_adapter(adapter->dev.parent), addr);
+
+ if (!result)
+ result = device_for_each_child(&adapter->dev, &addr,
+ i2c_check_mux_children);
+
+ return result;
+}
+
+/**
+ * i2c_lock_adapter - Get exclusive access to an I2C bus segment
+ * @adapter: Target I2C bus segment
+ */
+void i2c_lock_adapter(struct i2c_adapter *adapter)
+{
+ if (i2c_parent_is_i2c_adapter(adapter))
+ i2c_lock_adapter(to_i2c_adapter(adapter->dev.parent));
+ else
+ rt_mutex_lock(&adapter->bus_lock);
+}
+EXPORT_SYMBOL_GPL(i2c_lock_adapter);
+
+/**
+ * i2c_trylock_adapter - Try to get exclusive access to an I2C bus segment
+ * @adapter: Target I2C bus segment
+ */
+static int i2c_trylock_adapter(struct i2c_adapter *adapter)
+{
+ if (i2c_parent_is_i2c_adapter(adapter))
+ return i2c_trylock_adapter(to_i2c_adapter(adapter->dev.parent));
+ else
+ return rt_mutex_trylock(&adapter->bus_lock);
+}
+
+/**
+ * i2c_unlock_adapter - Release exclusive access to an I2C bus segment
+ * @adapter: Target I2C bus segment
+ */
+void i2c_unlock_adapter(struct i2c_adapter *adapter)
+{
+ if (i2c_parent_is_i2c_adapter(adapter))
+ i2c_unlock_adapter(to_i2c_adapter(adapter->dev.parent));
+ else
+ rt_mutex_unlock(&adapter->bus_lock);
}
+EXPORT_SYMBOL_GPL(i2c_unlock_adapter);
/**
* i2c_new_device - instantiate an i2c device
return -EINVAL;
/* Keep track of the added device */
- i2c_lock_adapter(adap);
+ mutex_lock(&adap->userspace_clients_lock);
list_add_tail(&client->detected, &adap->userspace_clients);
- i2c_unlock_adapter(adap);
+ mutex_unlock(&adap->userspace_clients_lock);
dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device",
info.type, info.addr);
/* Make sure the device was added through sysfs */
res = -ENOENT;
- i2c_lock_adapter(adap);
+ mutex_lock(&adap->userspace_clients_lock);
list_for_each_entry_safe(client, next, &adap->userspace_clients,
detected) {
if (client->addr == addr) {
break;
}
}
- i2c_unlock_adapter(adap);
+ mutex_unlock(&adap->userspace_clients_lock);
if (res < 0)
dev_err(dev, "%s: Can't find device in list\n",
NULL
};
-static struct device_type i2c_adapter_type = {
+struct device_type i2c_adapter_type = {
.groups = i2c_adapter_attr_groups,
.release = i2c_adapter_dev_release,
};
+EXPORT_SYMBOL_GPL(i2c_adapter_type);
#ifdef CONFIG_I2C_COMPAT
static struct class_compat *i2c_adapter_compat_class;
static int i2c_register_adapter(struct i2c_adapter *adap)
{
- int res = 0, dummy;
+ int res = 0;
/* Can't register until after driver model init */
if (unlikely(WARN_ON(!i2c_bus_type.p))) {
}
rt_mutex_init(&adap->bus_lock);
+ mutex_init(&adap->userspace_clients_lock);
INIT_LIST_HEAD(&adap->userspace_clients);
/* Set default timeout to 1 second if not already set */
/* Notify drivers */
mutex_lock(&core_lock);
- dummy = bus_for_each_drv(&i2c_bus_type, NULL, adap,
- __process_new_adapter);
+ bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter);
mutex_unlock(&core_lock);
return 0;
return res;
/* Remove devices instantiated from sysfs */
- i2c_lock_adapter(adap);
+ mutex_lock(&adap->userspace_clients_lock);
list_for_each_entry_safe(client, next, &adap->userspace_clients,
detected) {
dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name,
list_del(&client->detected);
i2c_unregister_device(client);
}
- i2c_unlock_adapter(adap);
+ mutex_unlock(&adap->userspace_clients_lock);
/* Detach any active clients. This can't fail, thus we do not
checking the returned value. */
#endif
if (in_atomic() || irqs_disabled()) {
- ret = rt_mutex_trylock(&adap->bus_lock);
+ ret = i2c_trylock_adapter(adap);
if (!ret)
/* I2C activity is ongoing. */
return -EAGAIN;
} else {
- rt_mutex_lock(&adap->bus_lock);
+ i2c_lock_adapter(adap);
}
/* Retry automatically on arbitration loss */
if (time_after(jiffies, orig_jiffies + adap->timeout))
break;
}
- rt_mutex_unlock(&adap->bus_lock);
+ i2c_unlock_adapter(adap);
return ret;
} else {
I2C_SMBUS_BYTE_DATA, &dummy);
else
#endif
- if ((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50
- || !i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK))
- err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0,
- I2C_SMBUS_BYTE, &dummy);
- else
+ if (!((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50)
+ && i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK))
err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0,
I2C_SMBUS_QUICK, NULL);
+ else if (i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE))
+ err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0,
+ I2C_SMBUS_BYTE, &dummy);
+ else {
+ dev_warn(&adap->dev, "No suitable probing method supported\n");
+ err = -EOPNOTSUPP;
+ }
return err >= 0;
}
if (!(adapter->class & driver->class))
goto exit_free;
- /* Stop here if the bus doesn't support probing */
- if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE)) {
- if (address_list[0] == I2C_CLIENT_END)
- goto exit_free;
-
- dev_warn(&adapter->dev, "Probing not supported\n");
- err = -EOPNOTSUPP;
- goto exit_free;
- }
-
for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) {
dev_dbg(&adapter->dev, "found normal entry for adapter %d, "
"addr 0x%02x\n", adap_id, address_list[i]);
return err;
}
+int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr)
+{
+ return i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0,
+ I2C_SMBUS_QUICK, NULL) >= 0;
+}
+EXPORT_SYMBOL_GPL(i2c_probe_func_quick_read);
+
struct i2c_client *
i2c_new_probed_device(struct i2c_adapter *adap,
struct i2c_board_info *info,
- unsigned short const *addr_list)
+ unsigned short const *addr_list,
+ int (*probe)(struct i2c_adapter *, unsigned short addr))
{
int i;
- /* Stop here if the bus doesn't support probing */
- if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) {
- dev_err(&adap->dev, "Probing not supported\n");
- return NULL;
- }
+ if (!probe)
+ probe = i2c_default_probe;
for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) {
/* Check address validity */
}
/* Test address responsiveness */
- if (i2c_default_probe(adap, addr_list[i]))
+ if (probe(adap, addr_list[i]))
break;
}
flags &= I2C_M_TEN | I2C_CLIENT_PEC;
if (adapter->algo->smbus_xfer) {
- rt_mutex_lock(&adapter->bus_lock);
+ i2c_lock_adapter(adapter);
/* Retry automatically on arbitration loss */
orig_jiffies = jiffies;
orig_jiffies + adapter->timeout))
break;
}
- rt_mutex_unlock(&adapter->bus_lock);
+ i2c_unlock_adapter(adapter);
} else
res = i2c_smbus_xfer_emulated(adapter, addr, flags, read_write,
command, protocol, data);
git.openpandora.org / pandora-kernel.git / blobdiff