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phy: improved lookup method
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Separates registration of the phy and the lookup. The method
is copied from clkdev.c,

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
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Heikki Krogerus authored and Kishon Vijay Abraham I committed Nov 21, 2014
1 parent d451057 commit b7bc15b
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Showing 3 changed files with 115 additions and 45 deletions.
60 changes: 16 additions & 44 deletions Documentation/phy.txt
Original file line number Diff line number Diff line change
Expand Up @@ -54,18 +54,14 @@ The PHY driver should create the PHY in order for other peripheral controllers
to make use of it. The PHY framework provides 2 APIs to create the PHY.

struct phy *phy_create(struct device *dev, struct device_node *node,
const struct phy_ops *ops,
struct phy_init_data *init_data);
const struct phy_ops *ops);
struct phy *devm_phy_create(struct device *dev, struct device_node *node,
const struct phy_ops *ops,
struct phy_init_data *init_data);
const struct phy_ops *ops);

The PHY drivers can use one of the above 2 APIs to create the PHY by passing
the device pointer, phy ops and init_data.
the device pointer and phy ops.
phy_ops is a set of function pointers for performing PHY operations such as
init, exit, power_on and power_off. *init_data* is mandatory to get a reference
to the PHY in the case of non-dt boot. See section *Board File Initialization*
on how init_data should be used.
init, exit, power_on and power_off.

Inorder to dereference the private data (in phy_ops), the phy provider driver
can use phy_set_drvdata() after creating the PHY and use phy_get_drvdata() in
Expand Down Expand Up @@ -137,42 +133,18 @@ There are exported APIs like phy_pm_runtime_get, phy_pm_runtime_get_sync,
phy_pm_runtime_put, phy_pm_runtime_put_sync, phy_pm_runtime_allow and
phy_pm_runtime_forbid for performing PM operations.

8. Board File Initialization

Certain board file initialization is necessary in order to get a reference
to the PHY in the case of non-dt boot.
Say we have a single device that implements 3 PHYs that of USB, SATA and PCIe,
then in the board file the following initialization should be done.

struct phy_consumer consumers[] = {
PHY_CONSUMER("dwc3.0", "usb"),
PHY_CONSUMER("pcie.0", "pcie"),
PHY_CONSUMER("sata.0", "sata"),
};
PHY_CONSUMER takes 2 parameters, first is the device name of the controller
(PHY consumer) and second is the port name.

struct phy_init_data init_data = {
.consumers = consumers,
.num_consumers = ARRAY_SIZE(consumers),
};

static const struct platform_device pipe3_phy_dev = {
.name = "pipe3-phy",
.id = -1,
.dev = {
.platform_data = {
.init_data = &init_data,
},
},
};

then, while doing phy_create, the PHY driver should pass this init_data
phy_create(dev, ops, pdata->init_data);

and the controller driver (phy consumer) should pass the port name along with
the device to get a reference to the PHY
phy_get(dev, "pcie");
8. PHY Mappings

In order to get reference to a PHY without help from DeviceTree, the framework
offers lookups which can be compared to clkdev that allow clk structures to be
bound to devices. A lookup can be made be made during runtime when a handle to
the struct phy already exists.

The framework offers the following API for registering and unregistering the
lookups.

int phy_create_lookup(struct phy *phy, const char *con_id, const char *dev_id);
void phy_remove_lookup(struct phy *phy, const char *con_id, const char *dev_id);

9. DeviceTree Binding

Expand Down
84 changes: 83 additions & 1 deletion drivers/phy/phy-core.c
Original file line number Diff line number Diff line change
Expand Up @@ -26,6 +26,7 @@
static struct class *phy_class;
static DEFINE_MUTEX(phy_provider_mutex);
static LIST_HEAD(phy_provider_list);
static LIST_HEAD(phys);
static DEFINE_IDA(phy_ida);

static void devm_phy_release(struct device *dev, void *res)
Expand Down Expand Up @@ -84,6 +85,87 @@ static struct phy *phy_lookup(struct device *device, const char *port)
return ERR_PTR(-ENODEV);
}

/**
* phy_create_lookup() - allocate and register PHY/device association
* @phy: the phy of the association
* @con_id: connection ID string on device
* @dev_id: the device of the association
*
* Creates and registers phy_lookup entry.
*/
int phy_create_lookup(struct phy *phy, const char *con_id, const char *dev_id)
{
struct phy_lookup *pl;

if (!phy || !dev_id || !con_id)
return -EINVAL;

pl = kzalloc(sizeof(*pl), GFP_KERNEL);
if (!pl)
return -ENOMEM;

pl->dev_id = dev_id;
pl->con_id = con_id;
pl->phy = phy;

mutex_lock(&phy_provider_mutex);
list_add_tail(&pl->node, &phys);
mutex_unlock(&phy_provider_mutex);

return 0;
}
EXPORT_SYMBOL_GPL(phy_create_lookup);

/**
* phy_remove_lookup() - find and remove PHY/device association
* @phy: the phy of the association
* @con_id: connection ID string on device
* @dev_id: the device of the association
*
* Finds and unregisters phy_lookup entry that was created with
* phy_create_lookup().
*/
void phy_remove_lookup(struct phy *phy, const char *con_id, const char *dev_id)
{
struct phy_lookup *pl;

if (!phy || !dev_id || !con_id)
return;

mutex_lock(&phy_provider_mutex);
list_for_each_entry(pl, &phys, node)
if (pl->phy == phy && !strcmp(pl->dev_id, dev_id) &&
!strcmp(pl->con_id, con_id)) {
list_del(&pl->node);
kfree(pl);
break;
}
mutex_unlock(&phy_provider_mutex);
}
EXPORT_SYMBOL_GPL(phy_remove_lookup);

static struct phy *phy_find(struct device *dev, const char *con_id)
{
const char *dev_id = dev_name(dev);
struct phy_lookup *p, *pl = NULL;
struct phy *phy;

mutex_lock(&phy_provider_mutex);
list_for_each_entry(p, &phys, node)
if (!strcmp(p->dev_id, dev_id) && !strcmp(p->con_id, con_id)) {
pl = p;
break;
}
mutex_unlock(&phy_provider_mutex);

phy = pl ? pl->phy : ERR_PTR(-ENODEV);

/* fall-back to the old lookup method for now */
if (IS_ERR(phy))
phy = phy_lookup(dev, con_id);
return phy;
}

static struct phy_provider *of_phy_provider_lookup(struct device_node *node)
{
struct phy_provider *phy_provider;
Expand Down Expand Up @@ -455,7 +537,7 @@ struct phy *phy_get(struct device *dev, const char *string)
string);
phy = _of_phy_get(dev->of_node, index);
} else {
phy = phy_lookup(dev, string);
phy = phy_find(dev, string);
}
if (IS_ERR(phy))
return phy;
Expand Down
16 changes: 16 additions & 0 deletions include/linux/phy/phy.h
Original file line number Diff line number Diff line change
Expand Up @@ -110,6 +110,13 @@ struct phy_init_data {
.port = _port, \
}

struct phy_lookup {
struct list_head node;
const char *dev_id;
const char *con_id;
struct phy *phy;
};

#define to_phy(a) (container_of((a), struct phy, dev))

#define of_phy_provider_register(dev, xlate) \
Expand Down Expand Up @@ -174,6 +181,8 @@ struct phy_provider *__devm_of_phy_provider_register(struct device *dev,
void of_phy_provider_unregister(struct phy_provider *phy_provider);
void devm_of_phy_provider_unregister(struct device *dev,
struct phy_provider *phy_provider);
int phy_create_lookup(struct phy *phy, const char *con_id, const char *dev_id);
void phy_remove_lookup(struct phy *phy, const char *con_id, const char *dev_id);
#else
static inline int phy_pm_runtime_get(struct phy *phy)
{
Expand Down Expand Up @@ -345,6 +354,13 @@ static inline void devm_of_phy_provider_unregister(struct device *dev,
struct phy_provider *phy_provider)
{
}
static inline int
phy_create_lookup(struct phy *phy, const char *con_id, const char *dev_id)
{
return 0;
}
static inline void phy_remove_lookup(struct phy *phy, const char *con_id,
const char *dev_id) { }
#endif

#endif /* __DRIVERS_PHY_H */

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