From patchwork Fri Aug 29 22:00:52 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Octavian Purdila X-Patchwork-Id: 384405 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id DE43E140111 for ; Sat, 30 Aug 2014 08:05:44 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751289AbaH2WFj (ORCPT ); Fri, 29 Aug 2014 18:05:39 -0400 Received: from mga11.intel.com ([192.55.52.93]:5490 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751253AbaH2WFa (ORCPT ); Fri, 29 Aug 2014 18:05:30 -0400 Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga102.fm.intel.com with ESMTP; 29 Aug 2014 15:05:29 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,862,1389772800"; d="scan'208";a="378882448" Received: from mfagerst-mobl.ger.corp.intel.com (HELO opurdila-mobl1.ger.corp.intel.com) ([10.252.15.201]) by FMSMGA003.fm.intel.com with ESMTP; 29 Aug 2014 15:01:03 -0700 From: Octavian Purdila To: gregkh@linuxfoundation.org, linus.walleij@linaro.org, gnurou@gmail.com, wsa@the-dreams.de, sameo@linux.intel.com, lee.jones@linaro.org Cc: arnd@arndb.de, johan@kernel.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, linux-gpio@vger.kernel.org, linux-i2c@vger.kernel.org, daniel.baluta@intel.com, laurentiu.palcu@intel.com, Octavian Purdila Subject: [PATCH v2 1/3] mfd: add support for Diolan DLN-2 devices Date: Sat, 30 Aug 2014 01:00:52 +0300 Message-Id: <1409349654-24841-2-git-send-email-octavian.purdila@intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1409349654-24841-1-git-send-email-octavian.purdila@intel.com> References: <1409349654-24841-1-git-send-email-octavian.purdila@intel.com> Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org This patch implements the USB part of the Diolan USB-I2C/SPI/GPIO Master Adapter DLN-2. Details about the device can be found here: https://www.diolan.com/i2c/i2c_interface.html. Information about the USB protocol can be found in the Programmer's Reference Manual [1], see section 1.7. Because the hardware has a single transmit endpoint and a single receive endpoint the communication between the various DLN2 drivers and the hardware will be muxed/demuxed by this driver. Each DLN2 module will be identified by the handle field within the DLN2 message header. If a DLN2 module issues multiple commands in parallel they will be identified by the echo counter field in the message header. The DLN2 modules can use the dln2_transfer() function to issue a command and wait for its response. They can also register a callback that is going to be called when a specific event id is generated by the device (e.g. GPIO interrupts). The device uses handle 0 for sending events. [1] https://www.diolan.com/downloads/dln-api-manual.pdf Signed-off-by: Octavian Purdila --- drivers/mfd/Kconfig | 9 + drivers/mfd/Makefile | 1 + drivers/mfd/dln2.c | 652 +++++++++++++++++++++++++++++++++++++++++++++++ include/linux/mfd/dln2.h | 64 +++++ 4 files changed, 726 insertions(+) create mode 100644 drivers/mfd/dln2.c create mode 100644 include/linux/mfd/dln2.h diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig index de5abf2..7bcf895 100644 --- a/drivers/mfd/Kconfig +++ b/drivers/mfd/Kconfig @@ -183,6 +183,15 @@ config MFD_DA9063 Additional drivers must be enabled in order to use the functionality of the device. +config MFD_DLN2 + tristate "Diolan DLN2 support" + select MFD_CORE + depends on USB + help + This adds support for Diolan USB-I2C/SPI/GPIO Master Adapter DLN-2. + Additional drivers must be enabled in order to use the functionality + of the device. + config MFD_MC13XXX tristate depends on (SPI_MASTER || I2C) diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile index f001487..591988d 100644 --- a/drivers/mfd/Makefile +++ b/drivers/mfd/Makefile @@ -169,6 +169,7 @@ obj-$(CONFIG_MFD_AS3711) += as3711.o obj-$(CONFIG_MFD_AS3722) += as3722.o obj-$(CONFIG_MFD_STW481X) += stw481x.o obj-$(CONFIG_MFD_IPAQ_MICRO) += ipaq-micro.o +obj-$(CONFIG_MFD_DLN2) += dln2.o intel-soc-pmic-objs := intel_soc_pmic_core.o intel_soc_pmic_crc.o obj-$(CONFIG_INTEL_SOC_PMIC) += intel-soc-pmic.o diff --git a/drivers/mfd/dln2.c b/drivers/mfd/dln2.c new file mode 100644 index 0000000..ccd44fe --- /dev/null +++ b/drivers/mfd/dln2.c @@ -0,0 +1,652 @@ +/* + * Driver for the Diolan DLN-2 USB adapter + * + * Copyright (c) 2014 Intel Corporation + * + * Derived from: + * i2c-diolan-u2c.c + * Copyright (c) 2010-2011 Ericsson AB + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define DRIVER_NAME "usb-dln2" + +struct dln2_header { + __le16 size; + __le16 id; + __le16 echo; + __le16 handle; +} __packed; + +struct dln2_response { + struct dln2_header hdr; + __le16 result; +} __packed; + +#define DLN2_GENERIC_MODULE_ID 0x00 +#define DLN2_GENERIC_CMD(cmd) DLN2_CMD(cmd, DLN2_GENERIC_MODULE_ID) +#define CMD_GET_DEVICE_VER DLN2_GENERIC_CMD(0x30) +#define CMD_GET_DEVICE_SN DLN2_GENERIC_CMD(0x31) + +#define DLN2_HW_ID 0x200 +#define DLN2_USB_TIMEOUT 200 /* in ms */ +#define DLN2_MAX_RX_SLOTS 16 +#define DLN2_MAX_MODULES 5 +#define DLN2_MAX_URBS 16 + +#define DLN2_HANDLE_GPIO_EVENT 0 +#define DLN2_HANDLE_CTRL 1 +#define DLN2_HANDLE_GPIO 2 +#define DLN2_HANDLE_I2C 3 + +/* Receive context used between the receive demultiplexer and the + * transfer routine. While sending a request the transfer routine + * will look for a free receive context and use it to wait for a + * response and to receive the URB and thus the response data. */ +struct dln2_rx_context { + struct completion done; + struct urb *urb; + bool connected; +}; + +/* Receive contexts for a particular DLN2 module (i2c, gpio, etc.). We + * use the handle header field to indentify the module in + * dln2_dev.mod_rx_slots and then the echo header field to index the + * slots field and find the receive context for a particular + * request. */ +struct dln2_mod_rx_slots { + /* RX slots bitmap */ + unsigned long bmap; + + /* used to wait for a free RX slot */ + wait_queue_head_t wq; + + /* used to wait for an RX operation to complete */ + struct dln2_rx_context slots[DLN2_MAX_RX_SLOTS]; + + /* avoid races between free_rx_slot and dln2_rx_transfer_cb */ + spinlock_t lock; +}; + +struct dln2_dev { + struct usb_device *usb_dev; + struct usb_interface *interface; + u8 ep_in; + u8 ep_out; + + struct urb *rx_urb[DLN2_MAX_URBS]; + void *rx_buf[DLN2_MAX_URBS]; + + struct dln2_mod_rx_slots mod_rx_slots[DLN2_MAX_MODULES]; + + struct list_head rx_cb_list; + spinlock_t rx_cb_lock; +}; + +static bool find_free_slot(struct dln2_mod_rx_slots *rxs, int *slot) +{ + unsigned long flags; + + spin_lock_irqsave(&rxs->lock, flags); + + *slot = find_first_zero_bit(&rxs->bmap, DLN2_MAX_RX_SLOTS); + + if (*slot < DLN2_MAX_RX_SLOTS) { + struct dln2_rx_context *rxc = &rxs->slots[*slot]; + + init_completion(&rxc->done); + set_bit(*slot, &rxs->bmap); + rxc->connected = true; + } + + spin_unlock_irqrestore(&rxs->lock, flags); + + return *slot < DLN2_MAX_RX_SLOTS; +} + +static int alloc_rx_slot(struct dln2_mod_rx_slots *rxs) +{ + int slot, ret; + + /* No need to timeout here, the wait is bounded by the timeout + * in _dln2_transfer */ + ret = wait_event_interruptible(rxs->wq, find_free_slot(rxs, &slot)); + if (ret < 0) + return ret; + + return slot; +} + +static void free_rx_slot(struct dln2_dev *dln2, struct dln2_mod_rx_slots *rxs, + int slot) +{ + struct urb *urb = NULL; + unsigned long flags; + struct dln2_rx_context *rxc; + struct device *dev = &dln2->interface->dev; + int ret; + + spin_lock_irqsave(&rxs->lock, flags); + + clear_bit(slot, &rxs->bmap); + + rxc = &rxs->slots[slot]; + rxc->connected = false; + urb = rxc->urb; + rxc->urb = NULL; + + spin_unlock_irqrestore(&rxs->lock, flags); + + if (urb) { + ret = usb_submit_urb(urb, GFP_KERNEL); + if (ret < 0) + dev_err(dev, "failed to re-submit RX URB: %d\n", ret); + } + + wake_up_interruptible(&rxs->wq); +} + +struct dln2_rx_cb_entry { + struct list_head list; + u16 id; + struct platform_device *pdev; + dln2_rx_cb_t callback; +}; + +int dln2_register_event_cb(struct platform_device *pdev, u16 id, + dln2_rx_cb_t rx_cb) +{ + struct dln2_dev *dln2 = dev_get_drvdata(pdev->dev.parent); + struct dln2_rx_cb_entry *i, *new; + unsigned long flags; + int ret = 0; + + new = kmalloc(sizeof(*new), GFP_KERNEL); + if (!new) + return -ENOMEM; + + new->id = id; + new->callback = rx_cb; + new->pdev = pdev; + + spin_lock_irqsave(&dln2->rx_cb_lock, flags); + + list_for_each_entry(i, &dln2->rx_cb_list, list) { + if (i->id == id) { + ret = -EBUSY; + break; + } + } + + if (!ret) + list_add(&new->list, &dln2->rx_cb_list); + + spin_unlock_irqrestore(&dln2->rx_cb_lock, flags); + + if (ret) + kfree(new); + + return ret; +} +EXPORT_SYMBOL(dln2_register_event_cb); + +void dln2_unregister_event_cb(struct platform_device *pdev, u16 id) +{ + struct dln2_dev *dln2 = dev_get_drvdata(pdev->dev.parent); + struct dln2_rx_cb_entry *i, *tmp; + unsigned long flags; + + spin_lock_irqsave(&dln2->rx_cb_lock, flags); + + list_for_each_entry_safe(i, tmp, &dln2->rx_cb_list, list) { + if (i->id == id) { + list_del(&i->list); + kfree(i); + } + } + + spin_unlock_irqrestore(&dln2->rx_cb_lock, flags); +} +EXPORT_SYMBOL(dln2_unregister_event_cb); + +static void dln2_rx_transfer(struct dln2_dev *dln2, struct urb *urb, + u16 handle, u16 rx_slot) +{ + struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[handle]; + struct dln2_rx_context *rxc; + struct device *dev = &dln2->interface->dev; + int err; + + spin_lock(&rxs->lock); + rxc = &rxs->slots[rx_slot]; + if (rxc->connected) { + rxc->urb = urb; + complete(&rxc->done); + } else { + dev_warn(dev, "droping response %d/%d", handle, rx_slot); + err = usb_submit_urb(urb, GFP_ATOMIC); + if (err < 0) + dev_err(dev, "failed to re-submit RX URB: %d\n", err); + } + spin_unlock(&rxs->lock); +} + +static void dln2_run_rx_callbacks(struct dln2_dev *dln2, u16 id, u16 echo, + void *data, int len) +{ + struct dln2_rx_cb_entry *i; + + spin_lock(&dln2->rx_cb_lock); + + list_for_each_entry(i, &dln2->rx_cb_list, list) + if (i->id == id) + i->callback(i->pdev, echo, data, len); + + spin_unlock(&dln2->rx_cb_lock); +} + +static void dln2_rx(struct urb *urb) +{ + struct dln2_dev *dln2 = urb->context; + struct dln2_header *hdr = urb->transfer_buffer; + struct device *dev = &dln2->interface->dev; + u16 id, echo, handle, size; + u8 *data; + int len, err; + + switch (urb->status) { + case 0: + /* success */ + break; + case -ECONNRESET: + case -ENOENT: + case -ESHUTDOWN: + case -EPIPE: + /* this urb is terminated, clean up */ + dev_dbg(dev, "urb shutting down with status %d\n", urb->status); + return; + default: + dev_dbg(dev, "nonzero urb status received %d\n", urb->status); + goto out; + } + + if (urb->actual_length < sizeof(struct dln2_header)) { + dev_err(dev, "short response: %d\n", urb->actual_length); + goto out; + } + + handle = le16_to_cpu(hdr->handle); + id = le16_to_cpu(hdr->id); + echo = le16_to_cpu(hdr->echo); + size = le16_to_cpu(hdr->size); + + if (size != urb->actual_length) { + dev_err(dev, "size mismatch: handle %x cmd %x echo %x size %d actual %d\n", + handle, id, echo, size, urb->actual_length); + goto out; + } + + if (handle > DLN2_MAX_MODULES) { + dev_warn(dev, "RX: invalid handle %d\n", handle); + goto out; + } + + data = urb->transfer_buffer + sizeof(struct dln2_header); + len = urb->actual_length - sizeof(struct dln2_header); + + if (!handle) { + dln2_run_rx_callbacks(dln2, id, echo, data, len); + err = usb_submit_urb(urb, GFP_ATOMIC); + if (err < 0) + goto out_submit_failed; + } else { + dln2_rx_transfer(dln2, urb, handle, echo); + } + + return; + +out: + err = usb_submit_urb(urb, GFP_ATOMIC); +out_submit_failed: + if (err < 0) + dev_err(dev, "failed to re-submit RX URB: %d\n", err); +} + +static void *dln2_prep_buf(u16 handle, u16 cmd, u16 echo, void *obuf, + int *obuf_len, gfp_t gfp) +{ + void *buf; + int len; + struct dln2_header *hdr; + + len = *obuf_len + sizeof(*hdr); + buf = kmalloc(len, gfp); + if (!buf) + return NULL; + + hdr = (struct dln2_header *)buf; + hdr->id = cpu_to_le16(cmd); + hdr->size = cpu_to_le16(len); + hdr->echo = cpu_to_le16(echo); + hdr->handle = cpu_to_le16(handle); + + memcpy(buf + sizeof(*hdr), obuf, *obuf_len); + + *obuf_len = len; + + return buf; +} + +static int dln2_send_wait(struct dln2_dev *dln2, u16 handle, u16 cmd, u16 echo, + void *obuf, int obuf_len) +{ + int len = obuf_len, ret = 0, actual; + void *buf; + + buf = dln2_prep_buf(handle, cmd, echo, obuf, &len, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + ret = usb_bulk_msg(dln2->usb_dev, + usb_sndbulkpipe(dln2->usb_dev, dln2->ep_out), + buf, len, &actual, DLN2_USB_TIMEOUT); + + kfree(buf); + + return ret; +} + +static int _dln2_transfer(struct dln2_dev *dln2, u16 handle, u16 cmd, + void *obuf, int obuf_len, void *ibuf, int *ibuf_len) +{ + u16 result, rx_slot; + struct dln2_response *rsp; + int ret = 0; + const int timeout = DLN2_USB_TIMEOUT * HZ / 1000; + struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[handle]; + struct dln2_rx_context *rxc; + struct device *dev = &dln2->interface->dev; + + rx_slot = alloc_rx_slot(rxs); + if (rx_slot < 0) + return rx_slot; + + ret = dln2_send_wait(dln2, handle, cmd, rx_slot, obuf, obuf_len); + if (ret < 0) { + free_rx_slot(dln2, rxs, rx_slot); + dev_err(dev, "USB write failed: %d", ret); + return ret; + } + + rxc = &rxs->slots[rx_slot]; + + ret = wait_for_completion_interruptible_timeout(&rxc->done, timeout); + if (ret <= 0) { + ret = !ret ? -ETIMEDOUT : ret; + goto out_free_rx_slot; + } + + /* if we got here we know that the response header has been checked */ + rsp = rxc->urb->transfer_buffer; + result = le16_to_cpu(rsp->result); + + if (result) { + dev_dbg(dev, "%d received response with error %d\n", + handle, result); + ret = -EREMOTEIO; + goto out_free_rx_slot; + } + + if (!ibuf) { + ret = 0; + goto out_free_rx_slot; + } + + if (*ibuf_len > rxc->urb->actual_length - sizeof(*rsp)) + *ibuf_len = rxc->urb->actual_length - sizeof(*rsp); + + memcpy(ibuf, rsp + 1, *ibuf_len); + +out_free_rx_slot: + free_rx_slot(dln2, rxs, rx_slot); + + return ret; +} + +struct dln2_platform_data { + u16 handle; +}; + +int dln2_transfer(struct platform_device *pdev, u16 cmd, + void *obuf, int obuf_len, void *ibuf, int *ibuf_len) +{ + struct dln2_platform_data *dln2_pdata; + struct dln2_dev *dln2; + u16 h; + + if (!pdev) + return -ENODEV; + + dln2 = dev_get_drvdata(pdev->dev.parent); + dln2_pdata = dev_get_platdata(&pdev->dev); + h = dln2_pdata->handle; + + return _dln2_transfer(dln2, h, cmd, obuf, obuf_len, ibuf, ibuf_len); +} +EXPORT_SYMBOL(dln2_transfer); + +static int dln2_check_hw(struct dln2_dev *dln2) +{ + __le32 hw_type; + int ret, len = sizeof(hw_type); + + ret = _dln2_transfer(dln2, DLN2_HANDLE_CTRL, CMD_GET_DEVICE_VER, + NULL, 0, &hw_type, &len); + if (ret < 0) + return ret; + + if (le32_to_cpu(hw_type) != DLN2_HW_ID) { + dev_err(&dln2->interface->dev, "Device ID 0x%x not supported!", + le32_to_cpu(hw_type)); + return -ENODEV; + } + + return 0; +} + +static int dln2_print_serialno(struct dln2_dev *dln2) +{ + __le32 serial_no; + int ret, len = sizeof(serial_no); + struct device *dev = &dln2->interface->dev; + + ret = _dln2_transfer(dln2, DLN2_HANDLE_CTRL, CMD_GET_DEVICE_SN, NULL, 0, + &serial_no, &len); + if (ret < 0) + return ret; + + dev_info(dev, "Diolan DLN2 serial 0x%x\n", le32_to_cpu(serial_no)); + + return 0; +} + +static int dln2_hw_init(struct dln2_dev *dln2) +{ + int ret = dln2_check_hw(dln2); + + if (ret < 0) + return ret; + + return dln2_print_serialno(dln2); +} + +static void dln2_free_rx_urbs(struct dln2_dev *dln2) +{ + int i; + + for (i = 0; i < DLN2_MAX_URBS; i++) { + usb_kill_urb(dln2->rx_urb[i]); + usb_free_urb(dln2->rx_urb[i]); + kfree(dln2->rx_buf[i]); + } +} + +static void dln2_free(struct dln2_dev *dln2) +{ + dln2_free_rx_urbs(dln2); + usb_put_dev(dln2->usb_dev); + kfree(dln2); +} + +static int dln2_setup_rx_urbs(struct dln2_dev *dln2, + struct usb_host_interface *hostif) +{ + int i, ret; + int rx_max_size = le16_to_cpu(hostif->endpoint[1].desc.wMaxPacketSize); + struct device *dev = &dln2->interface->dev; + + for (i = 0; i < DLN2_MAX_URBS; i++) { + dln2->rx_buf[i] = kmalloc(rx_max_size, GFP_KERNEL); + if (!dln2->rx_buf[i]) + return -ENOMEM; + + dln2->rx_urb[i] = usb_alloc_urb(0, GFP_KERNEL); + if (!dln2->rx_urb[i]) + return -ENOMEM; + + usb_fill_bulk_urb(dln2->rx_urb[i], dln2->usb_dev, + usb_rcvbulkpipe(dln2->usb_dev, dln2->ep_in), + dln2->rx_buf[i], rx_max_size, dln2_rx, dln2); + + ret = usb_submit_urb(dln2->rx_urb[i], GFP_KERNEL); + if (ret < 0) { + dev_err(dev, "failed to submit RX URB: %d\n", ret); + return ret; + } + } + + return 0; +} + +static struct dln2_platform_data dln2_pdata_gpio = { + .handle = DLN2_HANDLE_GPIO, +}; + +static struct dln2_platform_data dln2_pdata_i2c = { + .handle = DLN2_HANDLE_I2C, +}; + +static const struct mfd_cell dln2_devs[] = { + { + .name = "dln2-gpio", + .platform_data = &dln2_pdata_gpio, + .pdata_size = sizeof(struct dln2_platform_data), + }, + { + .name = "dln2-i2c", + .platform_data = &dln2_pdata_i2c, + .pdata_size = sizeof(struct dln2_platform_data), + }, +}; + +static void dln2_disconnect(struct usb_interface *interface) +{ + struct dln2_dev *dln2 = usb_get_intfdata(interface); + + mfd_remove_devices(&interface->dev); + dln2_free(dln2); +} + +static int dln2_probe(struct usb_interface *interface, + const struct usb_device_id *id) +{ + struct usb_host_interface *hostif = interface->cur_altsetting; + struct device *dev = &interface->dev; + struct dln2_dev *dln2; + int ret, i; + + if (hostif->desc.bInterfaceNumber != 0 || + hostif->desc.bNumEndpoints < 2) + return -ENODEV; + + dln2 = kzalloc(sizeof(*dln2), GFP_KERNEL); + if (!dln2) { + ret = -ENOMEM; + goto out; + } + + dln2->ep_out = hostif->endpoint[0].desc.bEndpointAddress; + dln2->ep_in = hostif->endpoint[1].desc.bEndpointAddress; + dln2->usb_dev = usb_get_dev(interface_to_usbdev(interface)); + dln2->interface = interface; + usb_set_intfdata(interface, dln2); + + for (i = 0; i < DLN2_MAX_MODULES; i++) { + init_waitqueue_head(&dln2->mod_rx_slots[i].wq); + spin_lock_init(&dln2->mod_rx_slots[i].lock); + } + + spin_lock_init(&dln2->rx_cb_lock); + INIT_LIST_HEAD(&dln2->rx_cb_list); + + ret = dln2_setup_rx_urbs(dln2, hostif); + if (ret) { + dln2_disconnect(interface); + return ret; + } + + ret = dln2_hw_init(dln2); + if (ret < 0) { + dev_err(dev, "failed to initialize hardware\n"); + goto out_cleanup; + } + + ret = mfd_add_devices(dev, -1, dln2_devs, ARRAY_SIZE(dln2_devs), + NULL, 0, NULL); + if (ret != 0) { + dev_err(dev, "Failed to add mfd devices to core.\n"); + goto out_cleanup; + } + + return 0; + +out_cleanup: + dln2_free(dln2); +out: + return ret; +} + +static const struct usb_device_id dln2_table[] = { + { USB_DEVICE(0xa257, 0x2013) }, + { } +}; + +MODULE_DEVICE_TABLE(usb, dln2_table); + +static struct usb_driver dln2_driver = { + .name = DRIVER_NAME, + .probe = dln2_probe, + .disconnect = dln2_disconnect, + .id_table = dln2_table, +}; + +module_usb_driver(dln2_driver); + +MODULE_AUTHOR("Octavian Purdila "); +MODULE_DESCRIPTION(DRIVER_NAME " driver"); +MODULE_LICENSE("GPL"); diff --git a/include/linux/mfd/dln2.h b/include/linux/mfd/dln2.h new file mode 100644 index 0000000..7ecbbe7 --- /dev/null +++ b/include/linux/mfd/dln2.h @@ -0,0 +1,64 @@ +#ifndef __LINUX_USB_DLN2_H +#define __LINUX_USB_DLN2_H + +#define DLN2_CMD(cmd, id) ((cmd) | ((id) << 8)) + +/** + * dln2_rx_cb - event callback function signature + * + * @pdev - the sub-driver that registered this callback + * @echo - the echo header field received in the message + * @data - the data payload + * @len - the data playload length + * + * The callback function is called in interrupt context and the data + * payload is only valid during the call. If the user needs later + * access of the data, it must copy it. + */ + +typedef void (*dln2_rx_cb_t)(struct platform_device *pdev, u16 echo, + const void *data, int len); + +/** + * dl2n_register_event_cb - register a callback function for an event + * + * @pdev - the sub-driver that registers the callback + * @event - the event for which to register a callback + * @rx_cb - the callback function + * + * @return 0 in case of success, negative value in case of error + */ +int dln2_register_event_cb(struct platform_device *pdev, u16 event, + dln2_rx_cb_t rx_cb); + +/** + * dln2_unregister_event_cb - unregister the callback function for an event + * + * @pdev - the sub-driver that registered the callback + * @event - the event for which to register a callback + */ +void dln2_unregister_event_cb(struct platform_device *pdev, u16 event); + +/** + * dln2_transfer - issue a DLN2 command and wait for a response and + * the associated data + * + * Only modules that did *NOT* register a receive callback will be + * able to use this function. + * + * @pdev - the DLN2 sub-device which is issueing this transfer + * @cmd - the command to be sent to the device + * @obuf - the buffer to be sent to the device; can be NULL if the + * user doesn't need to transmit data with this command + * @obuf_len - the size of the buffer to be sent to the device + * @ibuf - any data associated with the response will be copied here; + * it can be NULL if the user doesn't need the response data + * @ibuf_len - must be initialized to the input buffer size; it will + * be modified to indicate the actual data transfered + * + * @returns 0 for success, negative value for errors + */ +int dln2_transfer(struct platform_device *pdev, u16 cmd, + void *obuf, int obuf_len, void *ibuf, int *ibuf_len); + +#endif