From patchwork Mon Oct 11 09:06:22 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Carlos Chinea X-Patchwork-Id: 244991 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id o9B9732J014574 for ; Mon, 11 Oct 2010 09:07:03 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753926Ab0JKJFl (ORCPT ); Mon, 11 Oct 2010 05:05:41 -0400 Received: from mgw-sa02.ext.nokia.com ([147.243.1.48]:40748 "EHLO mgw-sa02.nokia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753129Ab0JKJFR (ORCPT ); Mon, 11 Oct 2010 05:05:17 -0400 Received: from localhost.localdomain (helruo-dhcp022198.ntc.nokia.com [172.21.22.198]) by mgw-sa02.nokia.com (Switch-3.4.3/Switch-3.4.3) with ESMTP id o9B95EHk012964; Mon, 11 Oct 2010 12:05:15 +0300 From: Carlos Chinea To: linux-kernel@vger.kernel.org Cc: linux-omap@vger.kernel.org Subject: [RFC PATCHv3 1/7] HSI: Introducing HSI framework Date: Mon, 11 Oct 2010 12:06:22 +0300 Message-Id: <1286787988-29013-2-git-send-email-carlos.chinea@nokia.com> X-Mailer: git-send-email 1.5.6.5 In-Reply-To: <1286787988-29013-1-git-send-email-carlos.chinea@nokia.com> References: <1286787988-29013-1-git-send-email-carlos.chinea@nokia.com> X-Nokia-AV: Clean Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter1.kernel.org [140.211.167.41]); Mon, 11 Oct 2010 09:07:03 +0000 (UTC) diff --git a/drivers/Kconfig b/drivers/Kconfig index a2b902f..4fe39f9 100644 --- a/drivers/Kconfig +++ b/drivers/Kconfig @@ -50,6 +50,8 @@ source "drivers/i2c/Kconfig" source "drivers/spi/Kconfig" +source "drivers/hsi/Kconfig" + source "drivers/pps/Kconfig" source "drivers/gpio/Kconfig" diff --git a/drivers/Makefile b/drivers/Makefile index 63e3aa9..6c6922a 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -47,6 +47,7 @@ obj-$(CONFIG_SCSI) += scsi/ obj-$(CONFIG_ATA) += ata/ obj-$(CONFIG_MTD) += mtd/ obj-$(CONFIG_SPI) += spi/ +obj-$(CONFIG_HSI) += hsi/ obj-y += net/ obj-$(CONFIG_ATM) += atm/ obj-$(CONFIG_FUSION) += message/ diff --git a/drivers/hsi/Kconfig b/drivers/hsi/Kconfig new file mode 100644 index 0000000..5af62ce --- /dev/null +++ b/drivers/hsi/Kconfig @@ -0,0 +1,13 @@ +# +# HSI driver configuration +# +menuconfig HSI + bool "HSI support" + ---help--- + The "High speed synchronous Serial Interface" is + synchronous serial interface used mainly to connect + application engines and cellular modems. + +if HSI + +endif # HSI diff --git a/drivers/hsi/Makefile b/drivers/hsi/Makefile new file mode 100644 index 0000000..b42b6cf --- /dev/null +++ b/drivers/hsi/Makefile @@ -0,0 +1,4 @@ +# +# Makefile for HSI +# +obj-$(CONFIG_HSI) += hsi.o diff --git a/drivers/hsi/hsi.c b/drivers/hsi/hsi.c new file mode 100644 index 0000000..78f1df4 --- /dev/null +++ b/drivers/hsi/hsi.c @@ -0,0 +1,516 @@ +/* + * hsi.c + * + * HSI core. + * + * Copyright (C) 2010 Nokia Corporation. All rights reserved. + * + * Contact: Carlos Chinea + * + * 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 +#include +#include +#include +#include +#include +#include +#include + +struct hsi_cl_info { + struct list_head list; + struct hsi_board_info info; +}; + +static LIST_HEAD(hsi_board_list); + +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) +{ + 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); + } +} + +/** + * 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; +} + +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; + } + 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; + 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); diff --git a/include/linux/hsi/hsi.h b/include/linux/hsi/hsi.h new file mode 100644 index 0000000..54ae22a --- /dev/null +++ b/include/linux/hsi/hsi.h @@ -0,0 +1,376 @@ +/* + * hsi.h + * + * HSI core header file. + * + * Copyright (C) 2010 Nokia Corporation. All rights reserved. + * + * Contact: Carlos Chinea + * + * 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_H__ +#define __LINUX_HSI_H__ + +#include +#include +#include +#include +#include + +/* HSI message ttype */ +#define HSI_MSG_READ 0 +#define HSI_MSG_WRITE 1 + +/* HSI configuration values */ +#define HSI_MODE_STREAM 1 +#define HSI_MODE_FRAME 2 +#define HSI_FLOW_SYNC 0 /* Synchronized flow */ +#define HSI_FLOW_PIPE 1 /* Pipelined flow */ +#define HSI_ARB_RR 0 /* Round-robin arbitration */ +#define HSI_ARB_PRIO 1 /* Channel priority arbitration */ + +#define HSI_MAX_CHANNELS 16 + +/* HSI message status codes */ +enum { + HSI_STATUS_COMPLETED, /* Message transfer is completed */ + HSI_STATUS_PENDING, /* Message pending to be read/write (POLL) */ + HSI_STATUS_PROCEEDING, /* Message transfer is ongoing */ + HSI_STATUS_QUEUED, /* Message waiting to be served */ + HSI_STATUS_ERROR, /* Error when message transfer was ongoing */ +}; + +/* HSI port event codes */ +enum { + HSI_EVENT_START_RX, + HSI_EVENT_STOP_RX, +}; + +/** + * struct hsi_config - Configuration for RX/TX HSI modules + * @mode: Bit transmission mode (STREAM or FRAME) + * @flow: Flow type (SYNCHRONIZED or PIPELINE) + * @channels: Number of channels to use [1..16] + * @speed: Max bit transmission speed (Kbit/s) + * @arb_mode: Arbitration mode for TX frame (Round robin, priority) + */ +struct hsi_config { + unsigned int mode; + unsigned int flow; + unsigned int channels; + unsigned int speed; + unsigned int arb_mode; /* TX only */ +}; + +/** + * struct hsi_board_info - HSI client board info + * @name: Name for the HSI device + * @hsi_id: HSI controller id where the client sits + * @port: Port number in the controller where the client sits + * @tx_cfg: HSI TX configuration + * @rx_cfg: HSI RX configuration + * @platform_data: Platform related data + * @archdata: Architecture-dependent device data + */ +struct hsi_board_info { + const char *name; + int hsi_id; + unsigned int port; + struct hsi_config tx_cfg; + struct hsi_config rx_cfg; + void *platform_data; + struct dev_archdata *archdata; +}; + +#ifdef CONFIG_HSI +extern int hsi_register_board_info(struct hsi_board_info const *info, + unsigned int len); +#else +static inline int hsi_register_board_info(struct hsi_board_info const *info, + unsigned int len) +{ + return 0; +} +#endif + +/** + * struct hsi_client - HSI client attached to an HSI port + * @device: Driver model representation of the device + * @tx_cfg: HSI TX configuration + * @rx_cfg: HSI RX configuration + * @hsi_start_rx: Called after incoming wake line goes high + * @hsi_stop_rx: Called after incoming wake line goes low + */ +struct hsi_client { + struct device device; + struct hsi_config tx_cfg; + struct hsi_config rx_cfg; + void (*hsi_start_rx)(struct hsi_client *cl); + void (*hsi_stop_rx)(struct hsi_client *cl); + /* private: */ + unsigned int pclaimed:1; + struct list_head link; +}; + +#define to_hsi_client(dev) container_of(dev, struct hsi_client, device) + +static inline void hsi_client_set_drvdata(struct hsi_client *cl, void *data) +{ + dev_set_drvdata(&cl->device, data); +} + +static inline void *hsi_client_drvdata(struct hsi_client *cl) +{ + return dev_get_drvdata(&cl->device); +} + +/** + * struct hsi_client_driver - Driver associated to an HSI client + * @driver: Driver model representation of the driver + */ +struct hsi_client_driver { + struct device_driver driver; +}; + +#define to_hsi_client_driver(drv) container_of(drv, struct hsi_client_driver,\ + driver) + +int hsi_register_client_driver(struct hsi_client_driver *drv); + +static inline void hsi_unregister_client_driver(struct hsi_client_driver *drv) +{ + driver_unregister(&drv->driver); +} + +/** + * struct hsi_msg - HSI message descriptor + * @link: Free to use by the current descriptor owner + * @cl: HSI device client that issues the transfer + * @sgt: Head of the scatterlist array + * @context: Client context data associated to the transfer + * @complete: Transfer completion callback + * @destructor: Destructor to free resources when flushing + * @status: Status of the transfer when completed + * @actual_len: Actual length of data transfered on completion + * @channel: Channel were to TX/RX the message + * @ttype: Transfer type (TX if set, RX otherwise) + * @break_frame: if true HSI will send/receive a break frame (FRAME MODE) + */ +struct hsi_msg { + struct list_head link; + struct hsi_client *cl; + struct sg_table sgt; + void *context; + + void (*complete)(struct hsi_msg *msg); + void (*destructor)(struct hsi_msg *msg); + + int status; + unsigned int actual_len; + unsigned int channel; + unsigned int ttype:1; + unsigned int break_frame:1; +}; + +struct hsi_msg *hsi_alloc_msg(unsigned int n_frag, gfp_t flags); +void hsi_free_msg(struct hsi_msg *msg); + +/** + * struct hsi_port - HSI port device + * @device: Driver model representation of the device + * @tx_cfg: Current TX path configuration + * @rx_cfg: Current RX path configuration + * @num: Port number + * @shared: Set when port can be shared by different clients + * @claimed: Reference count of clients which claimed the port + * @lock: Serialize port claim + * @async: Asynchronous transfer callback + * @setup: Callback to set the HSI client configuration + * @flush: Callback to clean the HW state and destroy all pending transfers + * @start_tx: Callback to inform that a client wants to TX data + * @stop_tx: Callback to inform that a client no longer wishes to TX data + * @release: Callback to inform that a client no longer uses the port + * @clients: List of hsi_clients using the port. + * @clock: Lock to serialize access to the clients list. + */ +struct hsi_port { + struct device device; + struct hsi_config tx_cfg; + struct hsi_config rx_cfg; + unsigned int num; + unsigned int shared:1; + int claimed; + struct mutex lock; + int (*async)(struct hsi_msg *msg); + int (*setup)(struct hsi_client *cl); + int (*flush)(struct hsi_client *cl); + int (*start_tx)(struct hsi_client *cl); + int (*stop_tx)(struct hsi_client *cl); + int (*release)(struct hsi_client *cl); + struct list_head clients; + spinlock_t clock; +}; + +#define to_hsi_port(dev) container_of(dev, struct hsi_port, device) +#define hsi_get_port(cl) to_hsi_port((cl)->device.parent) + +void hsi_event(struct hsi_port *port, unsigned int event); +int hsi_claim_port(struct hsi_client *cl, unsigned int share); +void hsi_release_port(struct hsi_client *cl); + +static inline int hsi_port_claimed(struct hsi_client *cl) +{ + return cl->pclaimed; +} + +static inline void hsi_port_set_drvdata(struct hsi_port *port, void *data) +{ + dev_set_drvdata(&port->device, data); +} + +static inline void *hsi_port_drvdata(struct hsi_port *port) +{ + return dev_get_drvdata(&port->device); +} + +/** + * struct hsi_controller - HSI controller device + * @device: Driver model representation of the device + * @id: HSI controller ID + * @num_ports: Number of ports in the HSI controller + * @port: Array of HSI ports + */ +struct hsi_controller { + struct device device; + int id; + unsigned int num_ports; + struct hsi_port *port; +}; + +#define to_hsi_controller(dev) container_of(dev, struct hsi_controller, device) + +struct hsi_controller *hsi_alloc_controller(unsigned int n_ports, gfp_t flags); +void hsi_free_controller(struct hsi_controller *hsi); +int hsi_register_controller(struct hsi_controller *hsi); +void hsi_unregister_controller(struct hsi_controller *hsi); + +static inline void hsi_controller_set_drvdata(struct hsi_controller *hsi, + void *data) +{ + dev_set_drvdata(&hsi->device, data); +} + +static inline void *hsi_controller_drvdata(struct hsi_controller *hsi) +{ + return dev_get_drvdata(&hsi->device); +} + +static inline struct hsi_port *hsi_find_port_num(struct hsi_controller *hsi, + unsigned int num) +{ + return (num < hsi->num_ports) ? &hsi->port[num] : NULL; +} + +/* + * API for HSI clients + */ +int hsi_async(struct hsi_client *cl, struct hsi_msg *msg); + +/** + * hsi_setup - Configure the client's port + * @cl: Pointer to the HSI client + * + * When sharing ports, clients should either relay on a single + * client setup or have the same setup for all of them. + * + * Return -errno on failure, 0 on success + */ +static inline int hsi_setup(struct hsi_client *cl) +{ + if (!hsi_port_claimed(cl)) + return -EACCES; + return hsi_get_port(cl)->setup(cl); +} + +/** + * hsi_flush - Flush all pending transactions on the client's port + * @cl: Pointer to the HSI client + * + * This function will destroy all pending hsi_msg in the port and reset + * the HW port so it is ready to receive and transmit from a clean state. + * + * Return -errno on failure, 0 on success + */ +static inline int hsi_flush(struct hsi_client *cl) +{ + if (!hsi_port_claimed(cl)) + return -EACCES; + return hsi_get_port(cl)->flush(cl); +} + +/** + * hsi_async_read - Submit a read transfer + * @cl: Pointer to the HSI client + * @msg: HSI message descriptor of the transfer + * + * Return -errno on failure, 0 on success + */ +static inline int hsi_async_read(struct hsi_client *cl, struct hsi_msg *msg) +{ + msg->ttype = HSI_MSG_READ; + return hsi_async(cl, msg); +} + +/** + * hsi_async_write - Submit a write transfer + * @cl: Pointer to the HSI client + * @msg: HSI message descriptor of the transfer + * + * Return -errno on failure, 0 on success + */ +static inline int hsi_async_write(struct hsi_client *cl, struct hsi_msg *msg) +{ + msg->ttype = HSI_MSG_WRITE; + return hsi_async(cl, msg); +} + +/** + * hsi_start_tx - Signal the port that the client wants to start a TX + * @cl: Pointer to the HSI client + * + * Return -errno on failure, 0 on success + */ +static inline int hsi_start_tx(struct hsi_client *cl) +{ + if (!hsi_port_claimed(cl)) + return -EACCES; + return hsi_get_port(cl)->start_tx(cl); +} + +/** + * hsi_stop_tx - Signal the port that the client no longer wants to transmit + * @cl: Pointer to the HSI client + * + * Return -errno on failure, 0 on success + */ +static inline int hsi_stop_tx(struct hsi_client *cl) +{ + if (!hsi_port_claimed(cl)) + return -EACCES; + return hsi_get_port(cl)->stop_tx(cl); +} +#endif /* __LINUX_HSI_H__ */