]> Pileus Git - ~andy/linux/blobdiff - drivers/hsi/hsi.c
Merge remote-tracking branch 'tip/perf/urgent' into perf/core
[~andy/linux] / drivers / hsi / hsi.c
index 4e2d79b793349c1d6c3b375677b2af7a87db2ccb..2d58f939d27f0ddbcf404909249c5f2d8f14a3a8 100644 (file)
  */
 #include <linux/hsi/hsi.h>
 #include <linux/compiler.h>
-#include <linux/rwsem.h>
 #include <linux/list.h>
-#include <linux/spinlock.h>
 #include <linux/kobject.h>
 #include <linux/slab.h>
 #include <linux/string.h>
+#include <linux/notifier.h>
 #include "hsi_core.h"
 
-static struct device_type hsi_ctrl = {
-       .name   = "hsi_controller",
-};
-
-static struct device_type hsi_cl = {
-       .name   = "hsi_client",
-};
-
-static struct device_type hsi_port = {
-       .name   = "hsi_port",
-};
-
 static ssize_t modalias_show(struct device *dev,
                        struct device_attribute *a __maybe_unused, char *buf)
 {
@@ -54,8 +41,7 @@ static struct device_attribute hsi_bus_dev_attrs[] = {
 
 static int hsi_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
-       if (dev->type == &hsi_cl)
-               add_uevent_var(env, "MODALIAS=hsi:%s", dev_name(dev));
+       add_uevent_var(env, "MODALIAS=hsi:%s", dev_name(dev));
 
        return 0;
 }
@@ -80,12 +66,10 @@ static void hsi_client_release(struct device *dev)
 static void hsi_new_client(struct hsi_port *port, struct hsi_board_info *info)
 {
        struct hsi_client *cl;
-       unsigned long flags;
 
        cl = kzalloc(sizeof(*cl), GFP_KERNEL);
        if (!cl)
                return;
-       cl->device.type = &hsi_cl;
        cl->tx_cfg = info->tx_cfg;
        cl->rx_cfg = info->rx_cfg;
        cl->device.bus = &hsi_bus_type;
@@ -93,14 +77,11 @@ static void hsi_new_client(struct hsi_port *port, struct hsi_board_info *info)
        cl->device.release = hsi_client_release;
        dev_set_name(&cl->device, info->name);
        cl->device.platform_data = info->platform_data;
-       spin_lock_irqsave(&port->clock, flags);
-       list_add_tail(&cl->link, &port->clients);
-       spin_unlock_irqrestore(&port->clock, flags);
        if (info->archdata)
                cl->device.archdata = *info->archdata;
        if (device_register(&cl->device) < 0) {
                pr_err("hsi: failed to register client: %s\n", info->name);
-               kfree(cl);
+               put_device(&cl->device);
        }
 }
 
@@ -120,13 +101,6 @@ static void hsi_scan_board_info(struct hsi_controller *hsi)
 
 static int hsi_remove_client(struct device *dev, void *data __maybe_unused)
 {
-       struct hsi_client *cl = to_hsi_client(dev);
-       struct hsi_port *port = to_hsi_port(dev->parent);
-       unsigned long flags;
-
-       spin_lock_irqsave(&port->clock, flags);
-       list_del(&cl->link);
-       spin_unlock_irqrestore(&port->clock, flags);
        device_unregister(dev);
 
        return 0;
@@ -140,12 +114,17 @@ static int hsi_remove_port(struct device *dev, void *data __maybe_unused)
        return 0;
 }
 
-static void hsi_controller_release(struct device *dev __maybe_unused)
+static void hsi_controller_release(struct device *dev)
 {
+       struct hsi_controller *hsi = to_hsi_controller(dev);
+
+       kfree(hsi->port);
+       kfree(hsi);
 }
 
-static void hsi_port_release(struct device *dev __maybe_unused)
+static void hsi_port_release(struct device *dev)
 {
+       kfree(to_hsi_port(dev));
 }
 
 /**
@@ -170,20 +149,12 @@ int hsi_register_controller(struct hsi_controller *hsi)
        unsigned int i;
        int err;
 
-       hsi->device.type = &hsi_ctrl;
-       hsi->device.bus = &hsi_bus_type;
-       hsi->device.release = hsi_controller_release;
-       err = device_register(&hsi->device);
+       err = device_add(&hsi->device);
        if (err < 0)
                return err;
        for (i = 0; i < hsi->num_ports; i++) {
-               hsi->port[i].device.parent = &hsi->device;
-               hsi->port[i].device.bus = &hsi_bus_type;
-               hsi->port[i].device.release = hsi_port_release;
-               hsi->port[i].device.type = &hsi_port;
-               INIT_LIST_HEAD(&hsi->port[i].clients);
-               spin_lock_init(&hsi->port[i].clock);
-               err = device_register(&hsi->port[i].device);
+               hsi->port[i]->device.parent = &hsi->device;
+               err = device_add(&hsi->port[i]->device);
                if (err < 0)
                        goto out;
        }
@@ -192,7 +163,9 @@ int hsi_register_controller(struct hsi_controller *hsi)
 
        return 0;
 out:
-       hsi_unregister_controller(hsi);
+       while (i-- > 0)
+               device_del(&hsi->port[i]->device);
+       device_del(&hsi->device);
 
        return err;
 }
@@ -222,6 +195,29 @@ static inline int hsi_dummy_cl(struct hsi_client *cl __maybe_unused)
        return 0;
 }
 
+/**
+ * hsi_put_controller - Free an HSI controller
+ *
+ * @hsi: Pointer to the HSI controller to freed
+ *
+ * HSI controller drivers should only use this function if they need
+ * to free their allocated hsi_controller structures before a successful
+ * call to hsi_register_controller. Other use is not allowed.
+ */
+void hsi_put_controller(struct hsi_controller *hsi)
+{
+       unsigned int i;
+
+       if (!hsi)
+               return;
+
+       for (i = 0; i < hsi->num_ports; i++)
+               if (hsi->port && hsi->port[i])
+                       put_device(&hsi->port[i]->device);
+       put_device(&hsi->device);
+}
+EXPORT_SYMBOL_GPL(hsi_put_controller);
+
 /**
  * hsi_alloc_controller - Allocate an HSI controller and its ports
  * @n_ports: Number of ports on the HSI controller
@@ -232,54 +228,51 @@ static inline int hsi_dummy_cl(struct hsi_client *cl __maybe_unused)
 struct hsi_controller *hsi_alloc_controller(unsigned int n_ports, gfp_t flags)
 {
        struct hsi_controller   *hsi;
-       struct hsi_port         *port;
+       struct hsi_port         **port;
        unsigned int            i;
 
        if (!n_ports)
                return NULL;
 
-       port = kzalloc(sizeof(*port)*n_ports, flags);
-       if (!port)
-               return NULL;
        hsi = kzalloc(sizeof(*hsi), flags);
        if (!hsi)
-               goto out;
-       for (i = 0; i < n_ports; i++) {
-               dev_set_name(&port[i].device, "port%d", i);
-               port[i].num = i;
-               port[i].async = hsi_dummy_msg;
-               port[i].setup = hsi_dummy_cl;
-               port[i].flush = hsi_dummy_cl;
-               port[i].start_tx = hsi_dummy_cl;
-               port[i].stop_tx = hsi_dummy_cl;
-               port[i].release = hsi_dummy_cl;
-               mutex_init(&port[i].lock);
+               return NULL;
+       port = kzalloc(sizeof(*port)*n_ports, flags);
+       if (!port) {
+               kfree(hsi);
+               return NULL;
        }
        hsi->num_ports = n_ports;
        hsi->port = port;
+       hsi->device.release = hsi_controller_release;
+       device_initialize(&hsi->device);
+
+       for (i = 0; i < n_ports; i++) {
+               port[i] = kzalloc(sizeof(**port), flags);
+               if (port[i] == NULL)
+                       goto out;
+               port[i]->num = i;
+               port[i]->async = hsi_dummy_msg;
+               port[i]->setup = hsi_dummy_cl;
+               port[i]->flush = hsi_dummy_cl;
+               port[i]->start_tx = hsi_dummy_cl;
+               port[i]->stop_tx = hsi_dummy_cl;
+               port[i]->release = hsi_dummy_cl;
+               mutex_init(&port[i]->lock);
+               ATOMIC_INIT_NOTIFIER_HEAD(&port[i]->n_head);
+               dev_set_name(&port[i]->device, "port%d", i);
+               hsi->port[i]->device.release = hsi_port_release;
+               device_initialize(&hsi->port[i]->device);
+       }
 
        return hsi;
 out:
-       kfree(port);
+       hsi_put_controller(hsi);
 
        return NULL;
 }
 EXPORT_SYMBOL_GPL(hsi_alloc_controller);
 
-/**
- * hsi_free_controller - Free an HSI controller
- * @hsi: Pointer to HSI controller
- */
-void hsi_free_controller(struct hsi_controller *hsi)
-{
-       if (!hsi)
-               return;
-
-       kfree(hsi->port);
-       kfree(hsi);
-}
-EXPORT_SYMBOL_GPL(hsi_free_controller);
-
 /**
  * hsi_free_msg - Free an HSI message
  * @msg: Pointer to the HSI message
@@ -414,37 +407,67 @@ void hsi_release_port(struct hsi_client *cl)
 }
 EXPORT_SYMBOL_GPL(hsi_release_port);
 
-static int hsi_start_rx(struct hsi_client *cl, void *data __maybe_unused)
+static int hsi_event_notifier_call(struct notifier_block *nb,
+                               unsigned long event, void *data __maybe_unused)
 {
-       if (cl->hsi_start_rx)
-               (*cl->hsi_start_rx)(cl);
+       struct hsi_client *cl = container_of(nb, struct hsi_client, nb);
+
+       (*cl->ehandler)(cl, event);
 
        return 0;
 }
 
-static int hsi_stop_rx(struct hsi_client *cl, void *data __maybe_unused)
+/**
+ * hsi_register_port_event - Register a client to receive port events
+ * @cl: HSI client that wants to receive port events
+ * @cb: Event handler callback
+ *
+ * Clients should register a callback to be able to receive
+ * events from the ports. Registration should happen after
+ * claiming the port.
+ * The handler can be called in interrupt context.
+ *
+ * Returns -errno on error, or 0 on success.
+ */
+int hsi_register_port_event(struct hsi_client *cl,
+                       void (*handler)(struct hsi_client *, unsigned long))
 {
-       if (cl->hsi_stop_rx)
-               (*cl->hsi_stop_rx)(cl);
+       struct hsi_port *port = hsi_get_port(cl);
 
-       return 0;
+       if (!handler || cl->ehandler)
+               return -EINVAL;
+       if (!hsi_port_claimed(cl))
+               return -EACCES;
+       cl->ehandler = handler;
+       cl->nb.notifier_call = hsi_event_notifier_call;
+
+       return atomic_notifier_chain_register(&port->n_head, &cl->nb);
 }
+EXPORT_SYMBOL_GPL(hsi_register_port_event);
 
-static int hsi_port_for_each_client(struct hsi_port *port, void *data,
-                               int (*fn)(struct hsi_client *cl, void *data))
+/**
+ * hsi_unregister_port_event - Stop receiving port events for a client
+ * @cl: HSI client that wants to stop receiving port events
+ *
+ * Clients should call this function before releasing their associated
+ * port.
+ *
+ * Returns -errno on error, or 0 on success.
+ */
+int hsi_unregister_port_event(struct hsi_client *cl)
 {
-       struct hsi_client *cl;
+       struct hsi_port *port = hsi_get_port(cl);
+       int err;
 
-       spin_lock(&port->clock);
-       list_for_each_entry(cl, &port->clients, link) {
-               spin_unlock(&port->clock);
-               (*fn)(cl, data);
-               spin_lock(&port->clock);
-       }
-       spin_unlock(&port->clock);
+       WARN_ON(!hsi_port_claimed(cl));
 
-       return 0;
+       err = atomic_notifier_chain_unregister(&port->n_head, &cl->nb);
+       if (!err)
+               cl->ehandler = NULL;
+
+       return err;
 }
+EXPORT_SYMBOL_GPL(hsi_unregister_port_event);
 
 /**
  * hsi_event -Notifies clients about port events
@@ -458,22 +481,12 @@ static int hsi_port_for_each_client(struct hsi_port *port, void *data,
  * Events:
  * HSI_EVENT_START_RX - Incoming wake line high
  * HSI_EVENT_STOP_RX - Incoming wake line down
+ *
+ * Returns -errno on error, or 0 on success.
  */
-void hsi_event(struct hsi_port *port, unsigned int event)
+int hsi_event(struct hsi_port *port, unsigned long event)
 {
-       int (*fn)(struct hsi_client *cl, void *data);
-
-       switch (event) {
-       case HSI_EVENT_START_RX:
-               fn = hsi_start_rx;
-               break;
-       case HSI_EVENT_STOP_RX:
-               fn = hsi_stop_rx;
-               break;
-       default:
-               return;
-       }
-       hsi_port_for_each_client(port, NULL, fn);
+       return atomic_notifier_call_chain(&port->n_head, event, NULL);
 }
 EXPORT_SYMBOL_GPL(hsi_event);