From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756390AbcJMPyQ (ORCPT ); Thu, 13 Oct 2016 11:54:16 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54280 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756348AbcJMPvy (ORCPT ); Thu, 13 Oct 2016 11:51:54 -0400 From: Benjamin Tissoires To: Dmitry Torokhov , Andrew Duggan , Lyude Paul , Christopher Heiny , Nick Dyer , Bjorn Andersson , Dennis Wassenberg Cc: linux-kernel@vger.kernel.org, linux-input@vger.kernel.org Subject: [PATCH v3 15/18] Input: synaptics-rmi4 - add rmi_platform Date: Thu, 13 Oct 2016 17:51:09 +0200 Message-Id: <1476373872-18027-16-git-send-email-benjamin.tissoires@redhat.com> In-Reply-To: <1476373872-18027-1-git-send-email-benjamin.tissoires@redhat.com> References: <1476373872-18027-1-git-send-email-benjamin.tissoires@redhat.com> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Thu, 13 Oct 2016 15:51:54 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This driver is a glue between PS/2 devices that enumerate the RMI4 device and the RMI4 SMBus driver. We mostly use an intermediate platform device to not add a dependency between psmouse and I2C. It also handles the subtleties of going around the serio mutex lock by deferring the i2c creation/destruction in a separate thread. Signed-off-by: Benjamin Tissoires --- no changes in v3 changes in v2: - use alloc_ordered_workqueue instead of create_singlethread_workqueue - Remove unneeded semicolon reported by scripts/coccinelle/misc/semicolon.cocci --- drivers/input/rmi4/Kconfig | 12 ++ drivers/input/rmi4/Makefile | 1 + drivers/input/rmi4/rmi_platform.c | 235 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 248 insertions(+) create mode 100644 drivers/input/rmi4/rmi_platform.c diff --git a/drivers/input/rmi4/Kconfig b/drivers/input/rmi4/Kconfig index eea1862..7a755fe 100644 --- a/drivers/input/rmi4/Kconfig +++ b/drivers/input/rmi4/Kconfig @@ -30,6 +30,7 @@ config RMI4_SPI config RMI4_SMB tristate "RMI4 SMB Support" depends on RMI4_CORE && I2C + select RMI4_PLATFORM help Say Y here if you want to support RMI4 devices connected to an SMB bus. @@ -39,6 +40,17 @@ config RMI4_SMB To compile this driver as a module, choose M here: the module will be called rmi_smbus. +config RMI4_PLATFORM + tristate "RMI4 Platform Support" + depends on RMI4_CORE && RMI4_SMB && I2C + help + Say Y here if you want to support RMI4 devices connected to an SMB + bus but enumerated through PS/2. + + if unsure, say N. + To compile this driver as a module, choose M here: the module will be + called rmi_platform. + config RMI4_F03 bool "RMI4 Function 03 (PS2 Guest)" depends on RMI4_CORE diff --git a/drivers/input/rmi4/Makefile b/drivers/input/rmi4/Makefile index 8271b65..c5a34ce 100644 --- a/drivers/input/rmi4/Makefile +++ b/drivers/input/rmi4/Makefile @@ -14,3 +14,4 @@ rmi_core-$(CONFIG_RMI4_F54) += rmi_f54.o obj-$(CONFIG_RMI4_I2C) += rmi_i2c.o obj-$(CONFIG_RMI4_SPI) += rmi_spi.o obj-$(CONFIG_RMI4_SMB) += rmi_smbus.o +obj-$(CONFIG_RMI4_PLATFORM) += rmi_platform.o diff --git a/drivers/input/rmi4/rmi_platform.c b/drivers/input/rmi4/rmi_platform.c new file mode 100644 index 0000000..6d31aea --- /dev/null +++ b/drivers/input/rmi4/rmi_platform.c @@ -0,0 +1,235 @@ +/* + * Copyright (c) 2016 Red Hat, Inc + * + * 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. + */ + +#include +#include +#include +#include +#include +#include + +#define DRIVER_DESC "RMI4 Platform PS/2 - SMBus bridge driver" + +MODULE_AUTHOR("Benjamin Tissoires "); +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_LICENSE("GPL"); + +static struct workqueue_struct *krmi_wq; +DEFINE_MUTEX(rmi_mutex); + +struct rmi_pltf { + struct i2c_client *smbus_client; + struct notifier_block i2c_notifier; + struct rmi_device_platform_data *pdata; +}; + +enum rmi_event_type { + RMI_REGISTER_DEVICE, + RMI_UNREGISTER_DEVICE, +}; + +struct rmi_work { + struct work_struct work; + enum rmi_event_type type; + struct rmi_pltf *rmi; + struct i2c_adapter *adap; +}; + +static void rmi_create_intertouch(struct rmi_pltf *rmi_pltf, + struct i2c_adapter *adap) +{ + const struct i2c_board_info i2c_info = { + I2C_BOARD_INFO("rmi4_smbus", 0x2c), + .platform_data = rmi_pltf->pdata, + }; + + rmi_pltf->smbus_client = i2c_new_device(adap, &i2c_info); +} + +static void rmi_worker(struct work_struct *work) +{ + struct rmi_work *rmi_work = container_of(work, struct rmi_work, work); + + mutex_lock(&rmi_mutex); + + switch (rmi_work->type) { + case RMI_REGISTER_DEVICE: + rmi_create_intertouch(rmi_work->rmi, rmi_work->adap); + break; + case RMI_UNREGISTER_DEVICE: + if (rmi_work->rmi->smbus_client) + i2c_unregister_device(rmi_work->rmi->smbus_client); + break; + } + + kfree(rmi_work); + + mutex_unlock(&rmi_mutex); +} + +static int rmi_schedule_work(enum rmi_event_type type, + struct rmi_pltf *rmi, + struct i2c_adapter *adap) +{ + struct rmi_work *rmi_work = kzalloc(sizeof(*rmi_work), GFP_KERNEL); + + if (!rmi_work) + return -ENOMEM; + + rmi_work->type = type; + rmi_work->rmi = rmi; + rmi_work->adap = adap; + + INIT_WORK(&rmi_work->work, rmi_worker); + + queue_work(krmi_wq, &rmi_work->work); + + return 0; +} + +static int rmi_attach_i2c_device(struct device *dev, void *data) +{ + struct rmi_pltf *rmi_pltf = data; + struct i2c_adapter *adap; + + if (dev->type != &i2c_adapter_type) + return 0; + + adap = to_i2c_adapter(dev); + + if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_HOST_NOTIFY)) + return 0; + + if (rmi_pltf->smbus_client) + return 0; + + rmi_schedule_work(RMI_REGISTER_DEVICE, rmi_pltf, adap); + + pr_debug("rmi_platform: adapter [%s] registered\n", adap->name); + return 0; +} + +static int rmi_detach_i2c_device(struct device *dev, struct rmi_pltf *rmi_pltf) +{ + struct i2c_client *client; + + if (dev->type == &i2c_adapter_type) + return 0; + + mutex_lock(&rmi_mutex); + + client = to_i2c_client(dev); + if (client == rmi_pltf->smbus_client) + rmi_pltf->smbus_client = NULL; + + mutex_unlock(&rmi_mutex); + + pr_debug("rmi_platform: client [%s] unregistered\n", client->name); + return 0; +} + +static int rmi_notifier_call(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct device *dev = data; + struct rmi_pltf *rmi_pltf; + + rmi_pltf = container_of(nb, struct rmi_pltf, i2c_notifier); + + switch (action) { + case BUS_NOTIFY_ADD_DEVICE: + return rmi_attach_i2c_device(dev, rmi_pltf); + case BUS_NOTIFY_DEL_DEVICE: + return rmi_detach_i2c_device(dev, rmi_pltf); + } + + return 0; +} + +static int rmi_probe(struct platform_device *pdev) +{ + struct rmi_device_platform_data *pdata = pdev->dev.platform_data; + struct rmi_pltf *rmi_pltf; + int error; + + rmi_pltf = devm_kzalloc(&pdev->dev, sizeof(struct rmi_pltf), + GFP_KERNEL); + if (!rmi_pltf) + return -ENOMEM; + + rmi_pltf->i2c_notifier.notifier_call = rmi_notifier_call; + + rmi_pltf->pdata = pdata; + + /* Keep track of adapters which will be added or removed later */ + error = bus_register_notifier(&i2c_bus_type, &rmi_pltf->i2c_notifier); + if (error) + return error; + + /* Bind to already existing adapters right away */ + i2c_for_each_dev(rmi_pltf, rmi_attach_i2c_device); + + platform_set_drvdata(pdev, rmi_pltf); + + return 0; +} + +static int rmi_remove(struct platform_device *pdev) +{ + struct rmi_pltf *rmi_pltf = platform_get_drvdata(pdev); + + bus_unregister_notifier(&i2c_bus_type, &rmi_pltf->i2c_notifier); + + if (rmi_pltf->smbus_client) + rmi_schedule_work(RMI_UNREGISTER_DEVICE, rmi_pltf, NULL); + + platform_set_drvdata(pdev, NULL); + + return 0; +} + +static const struct platform_device_id rmi_id_table[] = { + { .name = "rmi4" }, + { } +}; +MODULE_DEVICE_TABLE(platform, rmi_id_table); + +static struct platform_driver rmi_drv = { + .driver = { + .name = "rmi4", + }, + .probe = rmi_probe, + .remove = rmi_remove, + .id_table = rmi_id_table, +}; + +static int __init rmi_init(void) +{ + int err; + + krmi_wq = alloc_ordered_workqueue("krmid", WQ_MEM_RECLAIM); + if (!krmi_wq) { + pr_err("failed to create krmid workqueue\n"); + return -ENOMEM; + } + + err = platform_driver_register(&rmi_drv); + if (err) + destroy_workqueue(krmi_wq); + + return err; +} + +static void __exit rmi_exit(void) +{ + platform_driver_unregister(&rmi_drv); + destroy_workqueue(krmi_wq); +} + +module_init(rmi_init); +module_exit(rmi_exit); -- 2.7.4