diff options
Diffstat (limited to 'drivers/hsi')
| -rw-r--r-- | drivers/hsi/Kconfig | 17 | ||||
| -rw-r--r-- | drivers/hsi/Makefile | 5 | ||||
| -rw-r--r-- | drivers/hsi/hsi.c | 494 | ||||
| -rw-r--r-- | drivers/hsi/hsi_boardinfo.c | 62 | ||||
| -rw-r--r-- | drivers/hsi/hsi_core.h | 35 |
5 files changed, 613 insertions, 0 deletions
diff --git a/drivers/hsi/Kconfig b/drivers/hsi/Kconfig new file mode 100644 index 000000000000..937062e8bcd0 --- /dev/null +++ b/drivers/hsi/Kconfig @@ -0,0 +1,17 @@ +# +# HSI driver configuration +# +menuconfig HSI + tristate "HSI support" + ---help--- + The "High speed synchronous Serial Interface" is + synchronous serial interface used mainly to connect + application engines and cellular modems. + +if HSI + +config HSI_BOARDINFO + bool + default y + +endif # HSI diff --git a/drivers/hsi/Makefile b/drivers/hsi/Makefile new file mode 100644 index 000000000000..ed94a3a334a4 --- /dev/null +++ b/drivers/hsi/Makefile @@ -0,0 +1,5 @@ +# +# Makefile for HSI +# +obj-$(CONFIG_HSI_BOARDINFO) += hsi_boardinfo.o +obj-$(CONFIG_HSI) += hsi.o diff --git a/drivers/hsi/hsi.c b/drivers/hsi/hsi.c new file mode 100644 index 000000000000..4e2d79b79334 --- /dev/null +++ b/drivers/hsi/hsi.c @@ -0,0 +1,494 @@ +/* + * 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/rwsem.h> +#include <linux/list.h> +#include <linux/spinlock.h> +#include <linux/kobject.h> +#include <linux/slab.h> +#include <linux/string.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) +{ + return sprintf(buf, "hsi:%s\n", dev_name(dev)); +} + +static struct device_attribute hsi_bus_dev_attrs[] = { + __ATTR_RO(modalias), + __ATTR_NULL, +}; + +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)); + + return 0; +} + +static int hsi_bus_match(struct device *dev, struct device_driver *driver) +{ + return strcmp(dev_name(dev), driver->name) == 0; +} + +static struct bus_type hsi_bus_type = { + .name = "hsi", + .dev_attrs = hsi_bus_dev_attrs, + .match = hsi_bus_match, + .uevent = hsi_bus_uevent, +}; + +static void hsi_client_release(struct device *dev) +{ + kfree(to_hsi_client(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; + cl->device.parent = &port->device; + 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); + } +} + +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); + } +} + +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; +} + +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 __maybe_unused) +{ +} + +static void hsi_port_release(struct device *dev __maybe_unused) +{ +} + +/** + * 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; + + hsi->device.type = &hsi_ctrl; + hsi->device.bus = &hsi_bus_type; + hsi->device.release = hsi_controller_release; + err = device_register(&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); + if (err < 0) + goto out; + } + /* Populate HSI bus with HSI clients */ + hsi_scan_board_info(hsi); + + return 0; +out: + hsi_unregister_controller(hsi); + + 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_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; + + 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); + } + hsi->num_ports = n_ports; + hsi->port = port; + + return hsi; +out: + kfree(port); + + 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 + * + * 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_start_rx(struct hsi_client *cl, void *data __maybe_unused) +{ + if (cl->hsi_start_rx) + (*cl->hsi_start_rx)(cl); + + return 0; +} + +static int hsi_stop_rx(struct hsi_client *cl, void *data __maybe_unused) +{ + if (cl->hsi_stop_rx) + (*cl->hsi_stop_rx)(cl); + + return 0; +} + +static int hsi_port_for_each_client(struct hsi_port *port, void *data, + int (*fn)(struct hsi_client *cl, void *data)) +{ + struct hsi_client *cl; + + 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); + + return 0; +} + +/** + * 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 + */ +void hsi_event(struct hsi_port *port, unsigned int 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); +} +EXPORT_SYMBOL_GPL(hsi_event); + +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_boardinfo.c b/drivers/hsi/hsi_boardinfo.c new file mode 100644 index 000000000000..e56bc6da5f98 --- /dev/null +++ b/drivers/hsi/hsi_boardinfo.c @@ -0,0 +1,62 @@ +/* + * HSI clients registration interface + * + * 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/list.h> +#include <linux/slab.h> +#include "hsi_core.h" + +/* + * hsi_board_list is only used internally by the HSI framework. + * No one else is allowed to make use of it. + */ +LIST_HEAD(hsi_board_list); +EXPORT_SYMBOL_GPL(hsi_board_list); + +/** + * hsi_register_board_info - Register HSI clients information + * @info: Array of HSI clients on the board + * @len: Length of the array + * + * HSI clients are statically declared and registered on board files. + * + * HSI clients will be automatically registered to the HSI bus once the + * controller and the port where the clients wishes to attach are registered + * to it. + * + * Return -errno on failure, 0 on success. + */ +int __init hsi_register_board_info(struct hsi_board_info const *info, + unsigned int len) +{ + struct hsi_cl_info *cl_info; + + cl_info = kzalloc(sizeof(*cl_info) * len, GFP_KERNEL); + if (!cl_info) + return -ENOMEM; + + for (; len; len--, info++, cl_info++) { + cl_info->info = *info; + list_add_tail(&cl_info->list, &hsi_board_list); + } + + return 0; +} diff --git a/drivers/hsi/hsi_core.h b/drivers/hsi/hsi_core.h new file mode 100644 index 000000000000..ab5c2fb175fd --- /dev/null +++ b/drivers/hsi/hsi_core.h @@ -0,0 +1,35 @@ +/* + * HSI framework internal interfaces, + * + * 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 + */ + +#ifndef __LINUX_HSI_CORE_H__ +#define __LINUX_HSI_CORE_H__ + +#include <linux/hsi/hsi.h> + +struct hsi_cl_info { + struct list_head list; + struct hsi_board_info info; +}; + +extern struct list_head hsi_board_list; + +#endif /* __LINUX_HSI_CORE_H__ */ |