hsi: Build hsi_boardinfo.c into hsi core if enabled
authorAndrew F. Davis <afd@ti.com>
Tue, 14 Jun 2016 16:13:04 +0000 (11:13 -0500)
committerSebastian Reichel <sre@kernel.org>
Wed, 15 Jun 2016 14:02:50 +0000 (16:02 +0200)
If the HSI core is built as a module hsi_boardinfo may still
be built-in as its Kconfig type is bool, which can cause build
issues. Fix this by building this code into the HSI core when
enabled.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Documentation/DocBook/device-drivers.tmpl
drivers/hsi/Makefile
drivers/hsi/hsi.c [deleted file]
drivers/hsi/hsi_core.c [new file with mode: 0644]

index de79efdad46c2c691849b681b47c10f190658593..c245e4eea56035dcf59eb960dfe731297e7d8af3 100644 (file)
@@ -511,7 +511,7 @@ X!Ilib/fonts/fonts.c
      </para>
 
 !Iinclude/linux/hsi/hsi.h
-!Edrivers/hsi/hsi.c
+!Edrivers/hsi/hsi_core.c
   </chapter>
 
   <chapter id="pwm">
index 360371e134f17c11403586bc04aada637a523c6e..96944783d584f9bb1c44dc55bf84a537388739f4 100644 (file)
@@ -1,7 +1,8 @@
 #
 # Makefile for HSI
 #
-obj-$(CONFIG_HSI_BOARDINFO)    += hsi_boardinfo.o
 obj-$(CONFIG_HSI)              += hsi.o
+hsi-objs                       := hsi_core.o
+hsi-$(CONFIG_HSI_BOARDINFO)    += hsi_boardinfo.o
 obj-y                          += controllers/
 obj-y                          += clients/
diff --git a/drivers/hsi/hsi.c b/drivers/hsi/hsi.c
deleted file mode 100644 (file)
index d7ce07a..0000000
+++ /dev/null
@@ -1,781 +0,0 @@
-/*
- * HSI core.
- *
- * Copyright (C) 2010 Nokia Corporation. All rights reserved.
- *
- * Contact: Carlos Chinea <carlos.chinea@nokia.com>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * version 2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
- * 02110-1301 USA
- */
-#include <linux/hsi/hsi.h>
-#include <linux/compiler.h>
-#include <linux/list.h>
-#include <linux/kobject.h>
-#include <linux/slab.h>
-#include <linux/string.h>
-#include <linux/notifier.h>
-#include <linux/of.h>
-#include <linux/of_device.h>
-#include "hsi_core.h"
-
-static ssize_t modalias_show(struct device *dev,
-                       struct device_attribute *a __maybe_unused, char *buf)
-{
-       return sprintf(buf, "hsi:%s\n", dev_name(dev));
-}
-static DEVICE_ATTR_RO(modalias);
-
-static struct attribute *hsi_bus_dev_attrs[] = {
-       &dev_attr_modalias.attr,
-       NULL,
-};
-ATTRIBUTE_GROUPS(hsi_bus_dev);
-
-static int hsi_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
-{
-       add_uevent_var(env, "MODALIAS=hsi:%s", dev_name(dev));
-
-       return 0;
-}
-
-static int hsi_bus_match(struct device *dev, struct device_driver *driver)
-{
-       if (of_driver_match_device(dev, driver))
-               return true;
-
-       if (strcmp(dev_name(dev), driver->name) == 0)
-               return true;
-
-       return false;
-}
-
-static struct bus_type hsi_bus_type = {
-       .name           = "hsi",
-       .dev_groups     = hsi_bus_dev_groups,
-       .match          = hsi_bus_match,
-       .uevent         = hsi_bus_uevent,
-};
-
-static void hsi_client_release(struct device *dev)
-{
-       struct hsi_client *cl = to_hsi_client(dev);
-
-       kfree(cl->tx_cfg.channels);
-       kfree(cl->rx_cfg.channels);
-       kfree(cl);
-}
-
-struct hsi_client *hsi_new_client(struct hsi_port *port,
-                                               struct hsi_board_info *info)
-{
-       struct hsi_client *cl;
-       size_t size;
-
-       cl = kzalloc(sizeof(*cl), GFP_KERNEL);
-       if (!cl)
-               goto err;
-
-       cl->tx_cfg = info->tx_cfg;
-       if (cl->tx_cfg.channels) {
-               size = cl->tx_cfg.num_channels * sizeof(*cl->tx_cfg.channels);
-               cl->tx_cfg.channels = kmemdup(info->tx_cfg.channels, size,
-                                             GFP_KERNEL);
-               if (!cl->tx_cfg.channels)
-                       goto err_tx;
-       }
-
-       cl->rx_cfg = info->rx_cfg;
-       if (cl->rx_cfg.channels) {
-               size = cl->rx_cfg.num_channels * sizeof(*cl->rx_cfg.channels);
-               cl->rx_cfg.channels = kmemdup(info->rx_cfg.channels, size,
-                                             GFP_KERNEL);
-               if (!cl->rx_cfg.channels)
-                       goto err_rx;
-       }
-
-       cl->device.bus = &hsi_bus_type;
-       cl->device.parent = &port->device;
-       cl->device.release = hsi_client_release;
-       dev_set_name(&cl->device, "%s", info->name);
-       cl->device.platform_data = info->platform_data;
-       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);
-               put_device(&cl->device);
-       }
-
-       return cl;
-err_rx:
-       kfree(cl->tx_cfg.channels);
-err_tx:
-       kfree(cl);
-err:
-       return NULL;
-}
-EXPORT_SYMBOL_GPL(hsi_new_client);
-
-static void hsi_scan_board_info(struct hsi_controller *hsi)
-{
-       struct hsi_cl_info *cl_info;
-       struct hsi_port *p;
-
-       list_for_each_entry(cl_info, &hsi_board_list, list)
-               if (cl_info->info.hsi_id == hsi->id) {
-                       p = hsi_find_port_num(hsi, cl_info->info.port);
-                       if (!p)
-                               continue;
-                       hsi_new_client(p, &cl_info->info);
-               }
-}
-
-#ifdef CONFIG_OF
-static struct hsi_board_info hsi_char_dev_info = {
-       .name = "hsi_char",
-};
-
-static int hsi_of_property_parse_mode(struct device_node *client, char *name,
-                                     unsigned int *result)
-{
-       const char *mode;
-       int err;
-
-       err = of_property_read_string(client, name, &mode);
-       if (err < 0)
-               return err;
-
-       if (strcmp(mode, "stream") == 0)
-               *result = HSI_MODE_STREAM;
-       else if (strcmp(mode, "frame") == 0)
-               *result = HSI_MODE_FRAME;
-       else
-               return -EINVAL;
-
-       return 0;
-}
-
-static int hsi_of_property_parse_flow(struct device_node *client, char *name,
-                                     unsigned int *result)
-{
-       const char *flow;
-       int err;
-
-       err = of_property_read_string(client, name, &flow);
-       if (err < 0)
-               return err;
-
-       if (strcmp(flow, "synchronized") == 0)
-               *result = HSI_FLOW_SYNC;
-       else if (strcmp(flow, "pipeline") == 0)
-               *result = HSI_FLOW_PIPE;
-       else
-               return -EINVAL;
-
-       return 0;
-}
-
-static int hsi_of_property_parse_arb_mode(struct device_node *client,
-                                         char *name, unsigned int *result)
-{
-       const char *arb_mode;
-       int err;
-
-       err = of_property_read_string(client, name, &arb_mode);
-       if (err < 0)
-               return err;
-
-       if (strcmp(arb_mode, "round-robin") == 0)
-               *result = HSI_ARB_RR;
-       else if (strcmp(arb_mode, "priority") == 0)
-               *result = HSI_ARB_PRIO;
-       else
-               return -EINVAL;
-
-       return 0;
-}
-
-static void hsi_add_client_from_dt(struct hsi_port *port,
-                                               struct device_node *client)
-{
-       struct hsi_client *cl;
-       struct hsi_channel channel;
-       struct property *prop;
-       char name[32];
-       int length, cells, err, i, max_chan, mode;
-
-       cl = kzalloc(sizeof(*cl), GFP_KERNEL);
-       if (!cl)
-               return;
-
-       err = of_modalias_node(client, name, sizeof(name));
-       if (err)
-               goto err;
-
-       dev_set_name(&cl->device, "%s", name);
-
-       err = hsi_of_property_parse_mode(client, "hsi-mode", &mode);
-       if (err) {
-               err = hsi_of_property_parse_mode(client, "hsi-rx-mode",
-                                                &cl->rx_cfg.mode);
-               if (err)
-                       goto err;
-
-               err = hsi_of_property_parse_mode(client, "hsi-tx-mode",
-                                                &cl->tx_cfg.mode);
-               if (err)
-                       goto err;
-       } else {
-               cl->rx_cfg.mode = mode;
-               cl->tx_cfg.mode = mode;
-       }
-
-       err = of_property_read_u32(client, "hsi-speed-kbps",
-                                  &cl->tx_cfg.speed);
-       if (err)
-               goto err;
-       cl->rx_cfg.speed = cl->tx_cfg.speed;
-
-       err = hsi_of_property_parse_flow(client, "hsi-flow",
-                                        &cl->rx_cfg.flow);
-       if (err)
-               goto err;
-
-       err = hsi_of_property_parse_arb_mode(client, "hsi-arb-mode",
-                                            &cl->rx_cfg.arb_mode);
-       if (err)
-               goto err;
-
-       prop = of_find_property(client, "hsi-channel-ids", &length);
-       if (!prop) {
-               err = -EINVAL;
-               goto err;
-       }
-
-       cells = length / sizeof(u32);
-
-       cl->rx_cfg.num_channels = cells;
-       cl->tx_cfg.num_channels = cells;
-
-       cl->rx_cfg.channels = kzalloc(cells * sizeof(channel), GFP_KERNEL);
-       if (!cl->rx_cfg.channels) {
-               err = -ENOMEM;
-               goto err;
-       }
-
-       cl->tx_cfg.channels = kzalloc(cells * sizeof(channel), GFP_KERNEL);
-       if (!cl->tx_cfg.channels) {
-               err = -ENOMEM;
-               goto err2;
-       }
-
-       max_chan = 0;
-       for (i = 0; i < cells; i++) {
-               err = of_property_read_u32_index(client, "hsi-channel-ids", i,
-                                                &channel.id);
-               if (err)
-                       goto err3;
-
-               err = of_property_read_string_index(client, "hsi-channel-names",
-                                                   i, &channel.name);
-               if (err)
-                       channel.name = NULL;
-
-               if (channel.id > max_chan)
-                       max_chan = channel.id;
-
-               cl->rx_cfg.channels[i] = channel;
-               cl->tx_cfg.channels[i] = channel;
-       }
-
-       cl->rx_cfg.num_hw_channels = max_chan + 1;
-       cl->tx_cfg.num_hw_channels = max_chan + 1;
-
-       cl->device.bus = &hsi_bus_type;
-       cl->device.parent = &port->device;
-       cl->device.release = hsi_client_release;
-       cl->device.of_node = client;
-
-       if (device_register(&cl->device) < 0) {
-               pr_err("hsi: failed to register client: %s\n", name);
-               put_device(&cl->device);
-       }
-
-       return;
-
-err3:
-       kfree(cl->tx_cfg.channels);
-err2:
-       kfree(cl->rx_cfg.channels);
-err:
-       kfree(cl);
-       pr_err("hsi client: missing or incorrect of property: err=%d\n", err);
-}
-
-void hsi_add_clients_from_dt(struct hsi_port *port, struct device_node *clients)
-{
-       struct device_node *child;
-
-       /* register hsi-char device */
-       hsi_new_client(port, &hsi_char_dev_info);
-
-       for_each_available_child_of_node(clients, child)
-               hsi_add_client_from_dt(port, child);
-}
-EXPORT_SYMBOL_GPL(hsi_add_clients_from_dt);
-#endif
-
-int hsi_remove_client(struct device *dev, void *data __maybe_unused)
-{
-       device_unregister(dev);
-
-       return 0;
-}
-EXPORT_SYMBOL_GPL(hsi_remove_client);
-
-static int hsi_remove_port(struct device *dev, void *data __maybe_unused)
-{
-       device_for_each_child(dev, NULL, hsi_remove_client);
-       device_unregister(dev);
-
-       return 0;
-}
-
-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)
-{
-       kfree(to_hsi_port(dev));
-}
-
-/**
- * hsi_unregister_port - Unregister an HSI port
- * @port: The HSI port to unregister
- */
-void hsi_port_unregister_clients(struct hsi_port *port)
-{
-       device_for_each_child(&port->device, NULL, hsi_remove_client);
-}
-EXPORT_SYMBOL_GPL(hsi_port_unregister_clients);
-
-/**
- * hsi_unregister_controller - Unregister an HSI controller
- * @hsi: The HSI controller to register
- */
-void hsi_unregister_controller(struct hsi_controller *hsi)
-{
-       device_for_each_child(&hsi->device, NULL, hsi_remove_port);
-       device_unregister(&hsi->device);
-}
-EXPORT_SYMBOL_GPL(hsi_unregister_controller);
-
-/**
- * hsi_register_controller - Register an HSI controller and its ports
- * @hsi: The HSI controller to register
- *
- * Returns -errno on failure, 0 on success.
- */
-int hsi_register_controller(struct hsi_controller *hsi)
-{
-       unsigned int i;
-       int err;
-
-       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;
-               err = device_add(&hsi->port[i]->device);
-               if (err < 0)
-                       goto out;
-       }
-       /* Populate HSI bus with HSI clients */
-       hsi_scan_board_info(hsi);
-
-       return 0;
-out:
-       while (i-- > 0)
-               device_del(&hsi->port[i]->device);
-       device_del(&hsi->device);
-
-       return err;
-}
-EXPORT_SYMBOL_GPL(hsi_register_controller);
-
-/**
- * hsi_register_client_driver - Register an HSI client to the HSI bus
- * @drv: HSI client driver to register
- *
- * Returns -errno on failure, 0 on success.
- */
-int hsi_register_client_driver(struct hsi_client_driver *drv)
-{
-       drv->driver.bus = &hsi_bus_type;
-
-       return driver_register(&drv->driver);
-}
-EXPORT_SYMBOL_GPL(hsi_register_client_driver);
-
-static inline int hsi_dummy_msg(struct hsi_msg *msg __maybe_unused)
-{
-       return 0;
-}
-
-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
- * @flags: Kernel allocation flags
- *
- * Return NULL on failure or a pointer to an hsi_controller on success.
- */
-struct hsi_controller *hsi_alloc_controller(unsigned int n_ports, gfp_t flags)
-{
-       struct hsi_controller   *hsi;
-       struct hsi_port         **port;
-       unsigned int            i;
-
-       if (!n_ports)
-               return NULL;
-
-       hsi = kzalloc(sizeof(*hsi), flags);
-       if (!hsi)
-               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:
-       hsi_put_controller(hsi);
-
-       return NULL;
-}
-EXPORT_SYMBOL_GPL(hsi_alloc_controller);
-
-/**
- * hsi_free_msg - Free an HSI message
- * @msg: Pointer to the HSI message
- *
- * Client is responsible to free the buffers pointed by the scatterlists.
- */
-void hsi_free_msg(struct hsi_msg *msg)
-{
-       if (!msg)
-               return;
-       sg_free_table(&msg->sgt);
-       kfree(msg);
-}
-EXPORT_SYMBOL_GPL(hsi_free_msg);
-
-/**
- * hsi_alloc_msg - Allocate an HSI message
- * @nents: Number of memory entries
- * @flags: Kernel allocation flags
- *
- * nents can be 0. This mainly makes sense for read transfer.
- * In that case, HSI drivers will call the complete callback when
- * there is data to be read without consuming it.
- *
- * Return NULL on failure or a pointer to an hsi_msg on success.
- */
-struct hsi_msg *hsi_alloc_msg(unsigned int nents, gfp_t flags)
-{
-       struct hsi_msg *msg;
-       int err;
-
-       msg = kzalloc(sizeof(*msg), flags);
-       if (!msg)
-               return NULL;
-
-       if (!nents)
-               return msg;
-
-       err = sg_alloc_table(&msg->sgt, nents, flags);
-       if (unlikely(err)) {
-               kfree(msg);
-               msg = NULL;
-       }
-
-       return msg;
-}
-EXPORT_SYMBOL_GPL(hsi_alloc_msg);
-
-/**
- * hsi_async - Submit an HSI transfer to the controller
- * @cl: HSI client sending the transfer
- * @msg: The HSI transfer passed to controller
- *
- * The HSI message must have the channel, ttype, complete and destructor
- * fields set beforehand. If nents > 0 then the client has to initialize
- * also the scatterlists to point to the buffers to write to or read from.
- *
- * HSI controllers relay on pre-allocated buffers from their clients and they
- * do not allocate buffers on their own.
- *
- * Once the HSI message transfer finishes, the HSI controller calls the
- * complete callback with the status and actual_len fields of the HSI message
- * updated. The complete callback can be called before returning from
- * hsi_async.
- *
- * Returns -errno on failure or 0 on success
- */
-int hsi_async(struct hsi_client *cl, struct hsi_msg *msg)
-{
-       struct hsi_port *port = hsi_get_port(cl);
-
-       if (!hsi_port_claimed(cl))
-               return -EACCES;
-
-       WARN_ON_ONCE(!msg->destructor || !msg->complete);
-       msg->cl = cl;
-
-       return port->async(msg);
-}
-EXPORT_SYMBOL_GPL(hsi_async);
-
-/**
- * hsi_claim_port - Claim the HSI client's port
- * @cl: HSI client that wants to claim its port
- * @share: Flag to indicate if the client wants to share the port or not.
- *
- * Returns -errno on failure, 0 on success.
- */
-int hsi_claim_port(struct hsi_client *cl, unsigned int share)
-{
-       struct hsi_port *port = hsi_get_port(cl);
-       int err = 0;
-
-       mutex_lock(&port->lock);
-       if ((port->claimed) && (!port->shared || !share)) {
-               err = -EBUSY;
-               goto out;
-       }
-       if (!try_module_get(to_hsi_controller(port->device.parent)->owner)) {
-               err = -ENODEV;
-               goto out;
-       }
-       port->claimed++;
-       port->shared = !!share;
-       cl->pclaimed = 1;
-out:
-       mutex_unlock(&port->lock);
-
-       return err;
-}
-EXPORT_SYMBOL_GPL(hsi_claim_port);
-
-/**
- * hsi_release_port - Release the HSI client's port
- * @cl: HSI client which previously claimed its port
- */
-void hsi_release_port(struct hsi_client *cl)
-{
-       struct hsi_port *port = hsi_get_port(cl);
-
-       mutex_lock(&port->lock);
-       /* Allow HW driver to do some cleanup */
-       port->release(cl);
-       if (cl->pclaimed)
-               port->claimed--;
-       BUG_ON(port->claimed < 0);
-       cl->pclaimed = 0;
-       if (!port->claimed)
-               port->shared = 0;
-       module_put(to_hsi_controller(port->device.parent)->owner);
-       mutex_unlock(&port->lock);
-}
-EXPORT_SYMBOL_GPL(hsi_release_port);
-
-static int hsi_event_notifier_call(struct notifier_block *nb,
-                               unsigned long event, void *data __maybe_unused)
-{
-       struct hsi_client *cl = container_of(nb, struct hsi_client, nb);
-
-       (*cl->ehandler)(cl, event);
-
-       return 0;
-}
-
-/**
- * hsi_register_port_event - Register a client to receive port events
- * @cl: HSI client that wants to receive port events
- * @handler: 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))
-{
-       struct hsi_port *port = hsi_get_port(cl);
-
-       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);
-
-/**
- * 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_port *port = hsi_get_port(cl);
-       int err;
-
-       WARN_ON(!hsi_port_claimed(cl));
-
-       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
- * @port: Port where the event occurred
- * @event: The event type
- *
- * Clients should not be concerned about wake line behavior. However, due
- * to a race condition in HSI HW protocol, clients need to be notified
- * about wake line changes, so they can implement a workaround for it.
- *
- * 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.
- */
-int hsi_event(struct hsi_port *port, unsigned long event)
-{
-       return atomic_notifier_call_chain(&port->n_head, event, NULL);
-}
-EXPORT_SYMBOL_GPL(hsi_event);
-
-/**
- * hsi_get_channel_id_by_name - acquire channel id by channel name
- * @cl: HSI client, which uses the channel
- * @name: name the channel is known under
- *
- * Clients can call this function to get the hsi channel ids similar to
- * requesting IRQs or GPIOs by name. This function assumes the same
- * channel configuration is used for RX and TX.
- *
- * Returns -errno on error or channel id on success.
- */
-int hsi_get_channel_id_by_name(struct hsi_client *cl, char *name)
-{
-       int i;
-
-       if (!cl->rx_cfg.channels)
-               return -ENOENT;
-
-       for (i = 0; i < cl->rx_cfg.num_channels; i++)
-               if (!strcmp(cl->rx_cfg.channels[i].name, name))
-                       return cl->rx_cfg.channels[i].id;
-
-       return -ENXIO;
-}
-EXPORT_SYMBOL_GPL(hsi_get_channel_id_by_name);
-
-static int __init hsi_init(void)
-{
-       return bus_register(&hsi_bus_type);
-}
-postcore_initcall(hsi_init);
-
-static void __exit hsi_exit(void)
-{
-       bus_unregister(&hsi_bus_type);
-}
-module_exit(hsi_exit);
-
-MODULE_AUTHOR("Carlos Chinea <carlos.chinea@nokia.com>");
-MODULE_DESCRIPTION("High-speed Synchronous Serial Interface (HSI) framework");
-MODULE_LICENSE("GPL v2");
diff --git a/drivers/hsi/hsi_core.c b/drivers/hsi/hsi_core.c
new file mode 100644 (file)
index 0000000..d7ce07a
--- /dev/null
@@ -0,0 +1,781 @@
+/*
+ * HSI core.
+ *
+ * Copyright (C) 2010 Nokia Corporation. All rights reserved.
+ *
+ * Contact: Carlos Chinea <carlos.chinea@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+#include <linux/hsi/hsi.h>
+#include <linux/compiler.h>
+#include <linux/list.h>
+#include <linux/kobject.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/notifier.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include "hsi_core.h"
+
+static ssize_t modalias_show(struct device *dev,
+                       struct device_attribute *a __maybe_unused, char *buf)
+{
+       return sprintf(buf, "hsi:%s\n", dev_name(dev));
+}
+static DEVICE_ATTR_RO(modalias);
+
+static struct attribute *hsi_bus_dev_attrs[] = {
+       &dev_attr_modalias.attr,
+       NULL,
+};
+ATTRIBUTE_GROUPS(hsi_bus_dev);
+
+static int hsi_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+       add_uevent_var(env, "MODALIAS=hsi:%s", dev_name(dev));
+
+       return 0;
+}
+
+static int hsi_bus_match(struct device *dev, struct device_driver *driver)
+{
+       if (of_driver_match_device(dev, driver))
+               return true;
+
+       if (strcmp(dev_name(dev), driver->name) == 0)
+               return true;
+
+       return false;
+}
+
+static struct bus_type hsi_bus_type = {
+       .name           = "hsi",
+       .dev_groups     = hsi_bus_dev_groups,
+       .match          = hsi_bus_match,
+       .uevent         = hsi_bus_uevent,
+};
+
+static void hsi_client_release(struct device *dev)
+{
+       struct hsi_client *cl = to_hsi_client(dev);
+
+       kfree(cl->tx_cfg.channels);
+       kfree(cl->rx_cfg.channels);
+       kfree(cl);
+}
+
+struct hsi_client *hsi_new_client(struct hsi_port *port,
+                                               struct hsi_board_info *info)
+{
+       struct hsi_client *cl;
+       size_t size;
+
+       cl = kzalloc(sizeof(*cl), GFP_KERNEL);
+       if (!cl)
+               goto err;
+
+       cl->tx_cfg = info->tx_cfg;
+       if (cl->tx_cfg.channels) {
+               size = cl->tx_cfg.num_channels * sizeof(*cl->tx_cfg.channels);
+               cl->tx_cfg.channels = kmemdup(info->tx_cfg.channels, size,
+                                             GFP_KERNEL);
+               if (!cl->tx_cfg.channels)
+                       goto err_tx;
+       }
+
+       cl->rx_cfg = info->rx_cfg;
+       if (cl->rx_cfg.channels) {
+               size = cl->rx_cfg.num_channels * sizeof(*cl->rx_cfg.channels);
+               cl->rx_cfg.channels = kmemdup(info->rx_cfg.channels, size,
+                                             GFP_KERNEL);
+               if (!cl->rx_cfg.channels)
+                       goto err_rx;
+       }
+
+       cl->device.bus = &hsi_bus_type;
+       cl->device.parent = &port->device;
+       cl->device.release = hsi_client_release;
+       dev_set_name(&cl->device, "%s", info->name);
+       cl->device.platform_data = info->platform_data;
+       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);
+               put_device(&cl->device);
+       }
+
+       return cl;
+err_rx:
+       kfree(cl->tx_cfg.channels);
+err_tx:
+       kfree(cl);
+err:
+       return NULL;
+}
+EXPORT_SYMBOL_GPL(hsi_new_client);
+
+static void hsi_scan_board_info(struct hsi_controller *hsi)
+{
+       struct hsi_cl_info *cl_info;
+       struct hsi_port *p;
+
+       list_for_each_entry(cl_info, &hsi_board_list, list)
+               if (cl_info->info.hsi_id == hsi->id) {
+                       p = hsi_find_port_num(hsi, cl_info->info.port);
+                       if (!p)
+                               continue;
+                       hsi_new_client(p, &cl_info->info);
+               }
+}
+
+#ifdef CONFIG_OF
+static struct hsi_board_info hsi_char_dev_info = {
+       .name = "hsi_char",
+};
+
+static int hsi_of_property_parse_mode(struct device_node *client, char *name,
+                                     unsigned int *result)
+{
+       const char *mode;
+       int err;
+
+       err = of_property_read_string(client, name, &mode);
+       if (err < 0)
+               return err;
+
+       if (strcmp(mode, "stream") == 0)
+               *result = HSI_MODE_STREAM;
+       else if (strcmp(mode, "frame") == 0)
+               *result = HSI_MODE_FRAME;
+       else
+               return -EINVAL;
+
+       return 0;
+}
+
+static int hsi_of_property_parse_flow(struct device_node *client, char *name,
+                                     unsigned int *result)
+{
+       const char *flow;
+       int err;
+
+       err = of_property_read_string(client, name, &flow);
+       if (err < 0)
+               return err;
+
+       if (strcmp(flow, "synchronized") == 0)
+               *result = HSI_FLOW_SYNC;
+       else if (strcmp(flow, "pipeline") == 0)
+               *result = HSI_FLOW_PIPE;
+       else
+               return -EINVAL;
+
+       return 0;
+}
+
+static int hsi_of_property_parse_arb_mode(struct device_node *client,
+                                         char *name, unsigned int *result)
+{
+       const char *arb_mode;
+       int err;
+
+       err = of_property_read_string(client, name, &arb_mode);
+       if (err < 0)
+               return err;
+
+       if (strcmp(arb_mode, "round-robin") == 0)
+               *result = HSI_ARB_RR;
+       else if (strcmp(arb_mode, "priority") == 0)
+               *result = HSI_ARB_PRIO;
+       else
+               return -EINVAL;
+
+       return 0;
+}
+
+static void hsi_add_client_from_dt(struct hsi_port *port,
+                                               struct device_node *client)
+{
+       struct hsi_client *cl;
+       struct hsi_channel channel;
+       struct property *prop;
+       char name[32];
+       int length, cells, err, i, max_chan, mode;
+
+       cl = kzalloc(sizeof(*cl), GFP_KERNEL);
+       if (!cl)
+               return;
+
+       err = of_modalias_node(client, name, sizeof(name));
+       if (err)
+               goto err;
+
+       dev_set_name(&cl->device, "%s", name);
+
+       err = hsi_of_property_parse_mode(client, "hsi-mode", &mode);
+       if (err) {
+               err = hsi_of_property_parse_mode(client, "hsi-rx-mode",
+                                                &cl->rx_cfg.mode);
+               if (err)
+                       goto err;
+
+               err = hsi_of_property_parse_mode(client, "hsi-tx-mode",
+                                                &cl->tx_cfg.mode);
+               if (err)
+                       goto err;
+       } else {
+               cl->rx_cfg.mode = mode;
+               cl->tx_cfg.mode = mode;
+       }
+
+       err = of_property_read_u32(client, "hsi-speed-kbps",
+                                  &cl->tx_cfg.speed);
+       if (err)
+               goto err;
+       cl->rx_cfg.speed = cl->tx_cfg.speed;
+
+       err = hsi_of_property_parse_flow(client, "hsi-flow",
+                                        &cl->rx_cfg.flow);
+       if (err)
+               goto err;
+
+       err = hsi_of_property_parse_arb_mode(client, "hsi-arb-mode",
+                                            &cl->rx_cfg.arb_mode);
+       if (err)
+               goto err;
+
+       prop = of_find_property(client, "hsi-channel-ids", &length);
+       if (!prop) {
+               err = -EINVAL;
+               goto err;
+       }
+
+       cells = length / sizeof(u32);
+
+       cl->rx_cfg.num_channels = cells;
+       cl->tx_cfg.num_channels = cells;
+
+       cl->rx_cfg.channels = kzalloc(cells * sizeof(channel), GFP_KERNEL);
+       if (!cl->rx_cfg.channels) {
+               err = -ENOMEM;
+               goto err;
+       }
+
+       cl->tx_cfg.channels = kzalloc(cells * sizeof(channel), GFP_KERNEL);
+       if (!cl->tx_cfg.channels) {
+               err = -ENOMEM;
+               goto err2;
+       }
+
+       max_chan = 0;
+       for (i = 0; i < cells; i++) {
+               err = of_property_read_u32_index(client, "hsi-channel-ids", i,
+                                                &channel.id);
+               if (err)
+                       goto err3;
+
+               err = of_property_read_string_index(client, "hsi-channel-names",
+                                                   i, &channel.name);
+               if (err)
+                       channel.name = NULL;
+
+               if (channel.id > max_chan)
+                       max_chan = channel.id;
+
+               cl->rx_cfg.channels[i] = channel;
+               cl->tx_cfg.channels[i] = channel;
+       }
+
+       cl->rx_cfg.num_hw_channels = max_chan + 1;
+       cl->tx_cfg.num_hw_channels = max_chan + 1;
+
+       cl->device.bus = &hsi_bus_type;
+       cl->device.parent = &port->device;
+       cl->device.release = hsi_client_release;
+       cl->device.of_node = client;
+
+       if (device_register(&cl->device) < 0) {
+               pr_err("hsi: failed to register client: %s\n", name);
+               put_device(&cl->device);
+       }
+
+       return;
+
+err3:
+       kfree(cl->tx_cfg.channels);
+err2:
+       kfree(cl->rx_cfg.channels);
+err:
+       kfree(cl);
+       pr_err("hsi client: missing or incorrect of property: err=%d\n", err);
+}
+
+void hsi_add_clients_from_dt(struct hsi_port *port, struct device_node *clients)
+{
+       struct device_node *child;
+
+       /* register hsi-char device */
+       hsi_new_client(port, &hsi_char_dev_info);
+
+       for_each_available_child_of_node(clients, child)
+               hsi_add_client_from_dt(port, child);
+}
+EXPORT_SYMBOL_GPL(hsi_add_clients_from_dt);
+#endif
+
+int hsi_remove_client(struct device *dev, void *data __maybe_unused)
+{
+       device_unregister(dev);
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(hsi_remove_client);
+
+static int hsi_remove_port(struct device *dev, void *data __maybe_unused)
+{
+       device_for_each_child(dev, NULL, hsi_remove_client);
+       device_unregister(dev);
+
+       return 0;
+}
+
+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)
+{
+       kfree(to_hsi_port(dev));
+}
+
+/**
+ * hsi_unregister_port - Unregister an HSI port
+ * @port: The HSI port to unregister
+ */
+void hsi_port_unregister_clients(struct hsi_port *port)
+{
+       device_for_each_child(&port->device, NULL, hsi_remove_client);
+}
+EXPORT_SYMBOL_GPL(hsi_port_unregister_clients);
+
+/**
+ * hsi_unregister_controller - Unregister an HSI controller
+ * @hsi: The HSI controller to register
+ */
+void hsi_unregister_controller(struct hsi_controller *hsi)
+{
+       device_for_each_child(&hsi->device, NULL, hsi_remove_port);
+       device_unregister(&hsi->device);
+}
+EXPORT_SYMBOL_GPL(hsi_unregister_controller);
+
+/**
+ * hsi_register_controller - Register an HSI controller and its ports
+ * @hsi: The HSI controller to register
+ *
+ * Returns -errno on failure, 0 on success.
+ */
+int hsi_register_controller(struct hsi_controller *hsi)
+{
+       unsigned int i;
+       int err;
+
+       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;
+               err = device_add(&hsi->port[i]->device);
+               if (err < 0)
+                       goto out;
+       }
+       /* Populate HSI bus with HSI clients */
+       hsi_scan_board_info(hsi);
+
+       return 0;
+out:
+       while (i-- > 0)
+               device_del(&hsi->port[i]->device);
+       device_del(&hsi->device);
+
+       return err;
+}
+EXPORT_SYMBOL_GPL(hsi_register_controller);
+
+/**
+ * hsi_register_client_driver - Register an HSI client to the HSI bus
+ * @drv: HSI client driver to register
+ *
+ * Returns -errno on failure, 0 on success.
+ */
+int hsi_register_client_driver(struct hsi_client_driver *drv)
+{
+       drv->driver.bus = &hsi_bus_type;
+
+       return driver_register(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(hsi_register_client_driver);
+
+static inline int hsi_dummy_msg(struct hsi_msg *msg __maybe_unused)
+{
+       return 0;
+}
+
+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
+ * @flags: Kernel allocation flags
+ *
+ * Return NULL on failure or a pointer to an hsi_controller on success.
+ */
+struct hsi_controller *hsi_alloc_controller(unsigned int n_ports, gfp_t flags)
+{
+       struct hsi_controller   *hsi;
+       struct hsi_port         **port;
+       unsigned int            i;
+
+       if (!n_ports)
+               return NULL;
+
+       hsi = kzalloc(sizeof(*hsi), flags);
+       if (!hsi)
+               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:
+       hsi_put_controller(hsi);
+
+       return NULL;
+}
+EXPORT_SYMBOL_GPL(hsi_alloc_controller);
+
+/**
+ * hsi_free_msg - Free an HSI message
+ * @msg: Pointer to the HSI message
+ *
+ * Client is responsible to free the buffers pointed by the scatterlists.
+ */
+void hsi_free_msg(struct hsi_msg *msg)
+{
+       if (!msg)
+               return;
+       sg_free_table(&msg->sgt);
+       kfree(msg);
+}
+EXPORT_SYMBOL_GPL(hsi_free_msg);
+
+/**
+ * hsi_alloc_msg - Allocate an HSI message
+ * @nents: Number of memory entries
+ * @flags: Kernel allocation flags
+ *
+ * nents can be 0. This mainly makes sense for read transfer.
+ * In that case, HSI drivers will call the complete callback when
+ * there is data to be read without consuming it.
+ *
+ * Return NULL on failure or a pointer to an hsi_msg on success.
+ */
+struct hsi_msg *hsi_alloc_msg(unsigned int nents, gfp_t flags)
+{
+       struct hsi_msg *msg;
+       int err;
+
+       msg = kzalloc(sizeof(*msg), flags);
+       if (!msg)
+               return NULL;
+
+       if (!nents)
+               return msg;
+
+       err = sg_alloc_table(&msg->sgt, nents, flags);
+       if (unlikely(err)) {
+               kfree(msg);
+               msg = NULL;
+       }
+
+       return msg;
+}
+EXPORT_SYMBOL_GPL(hsi_alloc_msg);
+
+/**
+ * hsi_async - Submit an HSI transfer to the controller
+ * @cl: HSI client sending the transfer
+ * @msg: The HSI transfer passed to controller
+ *
+ * The HSI message must have the channel, ttype, complete and destructor
+ * fields set beforehand. If nents > 0 then the client has to initialize
+ * also the scatterlists to point to the buffers to write to or read from.
+ *
+ * HSI controllers relay on pre-allocated buffers from their clients and they
+ * do not allocate buffers on their own.
+ *
+ * Once the HSI message transfer finishes, the HSI controller calls the
+ * complete callback with the status and actual_len fields of the HSI message
+ * updated. The complete callback can be called before returning from
+ * hsi_async.
+ *
+ * Returns -errno on failure or 0 on success
+ */
+int hsi_async(struct hsi_client *cl, struct hsi_msg *msg)
+{
+       struct hsi_port *port = hsi_get_port(cl);
+
+       if (!hsi_port_claimed(cl))
+               return -EACCES;
+
+       WARN_ON_ONCE(!msg->destructor || !msg->complete);
+       msg->cl = cl;
+
+       return port->async(msg);
+}
+EXPORT_SYMBOL_GPL(hsi_async);
+
+/**
+ * hsi_claim_port - Claim the HSI client's port
+ * @cl: HSI client that wants to claim its port
+ * @share: Flag to indicate if the client wants to share the port or not.
+ *
+ * Returns -errno on failure, 0 on success.
+ */
+int hsi_claim_port(struct hsi_client *cl, unsigned int share)
+{
+       struct hsi_port *port = hsi_get_port(cl);
+       int err = 0;
+
+       mutex_lock(&port->lock);
+       if ((port->claimed) && (!port->shared || !share)) {
+               err = -EBUSY;
+               goto out;
+       }
+       if (!try_module_get(to_hsi_controller(port->device.parent)->owner)) {
+               err = -ENODEV;
+               goto out;
+       }
+       port->claimed++;
+       port->shared = !!share;
+       cl->pclaimed = 1;
+out:
+       mutex_unlock(&port->lock);
+
+       return err;
+}
+EXPORT_SYMBOL_GPL(hsi_claim_port);
+
+/**
+ * hsi_release_port - Release the HSI client's port
+ * @cl: HSI client which previously claimed its port
+ */
+void hsi_release_port(struct hsi_client *cl)
+{
+       struct hsi_port *port = hsi_get_port(cl);
+
+       mutex_lock(&port->lock);
+       /* Allow HW driver to do some cleanup */
+       port->release(cl);
+       if (cl->pclaimed)
+               port->claimed--;
+       BUG_ON(port->claimed < 0);
+       cl->pclaimed = 0;
+       if (!port->claimed)
+               port->shared = 0;
+       module_put(to_hsi_controller(port->device.parent)->owner);
+       mutex_unlock(&port->lock);
+}
+EXPORT_SYMBOL_GPL(hsi_release_port);
+
+static int hsi_event_notifier_call(struct notifier_block *nb,
+                               unsigned long event, void *data __maybe_unused)
+{
+       struct hsi_client *cl = container_of(nb, struct hsi_client, nb);
+
+       (*cl->ehandler)(cl, event);
+
+       return 0;
+}
+
+/**
+ * hsi_register_port_event - Register a client to receive port events
+ * @cl: HSI client that wants to receive port events
+ * @handler: 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))
+{
+       struct hsi_port *port = hsi_get_port(cl);
+
+       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);
+
+/**
+ * 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_port *port = hsi_get_port(cl);
+       int err;
+
+       WARN_ON(!hsi_port_claimed(cl));
+
+       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
+ * @port: Port where the event occurred
+ * @event: The event type
+ *
+ * Clients should not be concerned about wake line behavior. However, due
+ * to a race condition in HSI HW protocol, clients need to be notified
+ * about wake line changes, so they can implement a workaround for it.
+ *
+ * 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.
+ */
+int hsi_event(struct hsi_port *port, unsigned long event)
+{
+       return atomic_notifier_call_chain(&port->n_head, event, NULL);
+}
+EXPORT_SYMBOL_GPL(hsi_event);
+
+/**
+ * hsi_get_channel_id_by_name - acquire channel id by channel name
+ * @cl: HSI client, which uses the channel
+ * @name: name the channel is known under
+ *
+ * Clients can call this function to get the hsi channel ids similar to
+ * requesting IRQs or GPIOs by name. This function assumes the same
+ * channel configuration is used for RX and TX.
+ *
+ * Returns -errno on error or channel id on success.
+ */
+int hsi_get_channel_id_by_name(struct hsi_client *cl, char *name)
+{
+       int i;
+
+       if (!cl->rx_cfg.channels)
+               return -ENOENT;
+
+       for (i = 0; i < cl->rx_cfg.num_channels; i++)
+               if (!strcmp(cl->rx_cfg.channels[i].name, name))
+                       return cl->rx_cfg.channels[i].id;
+
+       return -ENXIO;
+}
+EXPORT_SYMBOL_GPL(hsi_get_channel_id_by_name);
+
+static int __init hsi_init(void)
+{
+       return bus_register(&hsi_bus_type);
+}
+postcore_initcall(hsi_init);
+
+static void __exit hsi_exit(void)
+{
+       bus_unregister(&hsi_bus_type);
+}
+module_exit(hsi_exit);
+
+MODULE_AUTHOR("Carlos Chinea <carlos.chinea@nokia.com>");
+MODULE_DESCRIPTION("High-speed Synchronous Serial Interface (HSI) framework");
+MODULE_LICENSE("GPL v2");