From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S940124AbdAJQL4 (ORCPT ); Tue, 10 Jan 2017 11:11:56 -0500 Received: from mx1.redhat.com ([209.132.183.28]:54692 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S940038AbdAJQLu (ORCPT ); Tue, 10 Jan 2017 11:11:50 -0500 From: Benjamin Tissoires To: Dmitry Torokhov , KT Liao , Andrew Duggan Cc: Adrian Alves , linux-kernel@vger.kernel.org, linux-input@vger.kernel.org Subject: [PATCH 08/10] Input: add a PS/2 to SMBus platform module Date: Tue, 10 Jan 2017 17:11:26 +0100 Message-Id: <20170110161128.7441-9-benjamin.tissoires@redhat.com> In-Reply-To: <20170110161128.7441-1-benjamin.tissoires@redhat.com> References: <20170110161128.7441-1-benjamin.tissoires@redhat.com> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Tue, 10 Jan 2017 16:11:51 +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 devices and Elan touchpads to the RMI4 (or Elan) SMBus driver. We 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 --- drivers/input/misc/Kconfig | 11 ++ drivers/input/misc/Makefile | 1 + drivers/input/misc/ps2_smbus.c | 255 +++++++++++++++++++++++++++++++++++++++++ drivers/input/rmi4/Kconfig | 1 + 4 files changed, 268 insertions(+) create mode 100644 drivers/input/misc/ps2_smbus.c diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig index 1ae4d96..e0dfefc 100644 --- a/drivers/input/misc/Kconfig +++ b/drivers/input/misc/Kconfig @@ -832,4 +832,15 @@ config INPUT_HISI_POWERKEY To compile this driver as a module, choose M here: the module will be called hisi_powerkey. +config PS2_SMBUS + tristate "Platform Support for PS/2 Nodes also connected over SMBus" + depends on I2C + help + Say Y here if you want to support RMI4 or Elan 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 ps2_smbus. + endif diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile index 0b6d025..094a911 100644 --- a/drivers/input/misc/Makefile +++ b/drivers/input/misc/Makefile @@ -57,6 +57,7 @@ obj-$(CONFIG_INPUT_PCSPKR) += pcspkr.o obj-$(CONFIG_INPUT_PM8941_PWRKEY) += pm8941-pwrkey.o obj-$(CONFIG_INPUT_PM8XXX_VIBRATOR) += pm8xxx-vibrator.o obj-$(CONFIG_INPUT_PMIC8XXX_PWRKEY) += pmic8xxx-pwrkey.o +obj-$(CONFIG_PS2_SMBUS) += ps2_smbus.o obj-$(CONFIG_INPUT_POWERMATE) += powermate.o obj-$(CONFIG_INPUT_PWM_BEEPER) += pwm-beeper.o obj-$(CONFIG_INPUT_RB532_BUTTON) += rb532_button.o diff --git a/drivers/input/misc/ps2_smbus.c b/drivers/input/misc/ps2_smbus.c new file mode 100644 index 0000000..d1f27ed --- /dev/null +++ b/drivers/input/misc/ps2_smbus.c @@ -0,0 +1,255 @@ +/* + * Copyright (c) 2017 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 +#include + +MODULE_AUTHOR("Benjamin Tissoires "); +MODULE_DESCRIPTION("Platform PS/2 - SMBus bridge driver"); +MODULE_LICENSE("GPL"); + +static struct workqueue_struct *kps2smbus_wq; +DEFINE_MUTEX(ps2smbus_mutex); + +enum ps2smbus_type { + PS2SMBUS_SYNAPTICS_RMI4, +}; + +struct ps2smbus { + struct i2c_client *smbus_client; + struct notifier_block i2c_notifier; + enum ps2smbus_type type; + void *pdata; +}; + +enum ps2smbus_event_type { + PS2SMBUS_REGISTER_DEVICE, + PS2SMBUS_UNREGISTER_DEVICE, +}; + +struct ps2smbus_work { + struct work_struct work; + enum ps2smbus_event_type type; + struct ps2smbus *ps2smbus; + struct i2c_adapter *adap; +}; + +static void ps2smbus_create_rmi4(struct ps2smbus *ps2smbus, + struct i2c_adapter *adap) +{ + const struct i2c_board_info i2c_info = { + I2C_BOARD_INFO("rmi4_smbus", 0x2c), + .platform_data = ps2smbus->pdata, + .flags = I2C_CLIENT_HOST_NOTIFY, + }; + + ps2smbus->smbus_client = i2c_new_device(adap, &i2c_info); +} + +static void ps2smbus_worker(struct work_struct *work) +{ + struct ps2smbus_work *ps2smbus_work; + struct i2c_client *client; + + ps2smbus_work = container_of(work, struct ps2smbus_work, work); + client = ps2smbus_work->ps2smbus->smbus_client; + + mutex_lock(&ps2smbus_mutex); + + switch (ps2smbus_work->type) { + case PS2SMBUS_REGISTER_DEVICE: + if (ps2smbus_work->ps2smbus->type == PS2SMBUS_SYNAPTICS_RMI4) + ps2smbus_create_rmi4(ps2smbus_work->ps2smbus, + ps2smbus_work->adap); + break; + case PS2SMBUS_UNREGISTER_DEVICE: + if (client) + i2c_unregister_device(client); + break; + } + + kfree(ps2smbus_work); + + mutex_unlock(&ps2smbus_mutex); +} + +static int ps2smbus_schedule_work(enum ps2smbus_event_type type, + struct ps2smbus *ps2smbus, + struct i2c_adapter *adap) +{ + struct ps2smbus_work *ps2smbus_work; + + ps2smbus_work = kzalloc(sizeof(*ps2smbus_work), GFP_KERNEL); + if (!ps2smbus_work) + return -ENOMEM; + + ps2smbus_work->type = type; + ps2smbus_work->ps2smbus = ps2smbus; + ps2smbus_work->adap = adap; + + INIT_WORK(&ps2smbus_work->work, ps2smbus_worker); + + queue_work(kps2smbus_wq, &ps2smbus_work->work); + + return 0; +} + +static int ps2smbus_attach_i2c_device(struct device *dev, void *data) +{ + struct ps2smbus *ps2smbus = 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 (ps2smbus->smbus_client) + return 0; + + ps2smbus_schedule_work(PS2SMBUS_REGISTER_DEVICE, ps2smbus, adap); + + pr_debug("ps2smbus: adapter [%s] registered\n", adap->name); + return 0; +} + +static int ps2smbus_detach_i2c_device(struct device *dev, + struct ps2smbus *ps2smbus) +{ + struct i2c_client *client; + + if (dev->type == &i2c_adapter_type) + return 0; + + mutex_lock(&ps2smbus_mutex); + + client = to_i2c_client(dev); + if (client == ps2smbus->smbus_client) + ps2smbus->smbus_client = NULL; + + mutex_unlock(&ps2smbus_mutex); + + pr_debug("ps2smbus: client [%s] unregistered\n", client->name); + return 0; +} + +static int ps2smbus_notifier_call(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct device *dev = data; + struct ps2smbus *ps2smbus; + + ps2smbus = container_of(nb, struct ps2smbus, i2c_notifier); + + switch (action) { + case BUS_NOTIFY_ADD_DEVICE: + return ps2smbus_attach_i2c_device(dev, ps2smbus); + case BUS_NOTIFY_DEL_DEVICE: + return ps2smbus_detach_i2c_device(dev, ps2smbus); + } + + return 0; +} + +static int ps2smbus_probe(struct platform_device *pdev) +{ + struct rmi_device_platform_data *rmi_pdata = pdev->dev.platform_data; + struct serio *parent; + struct ps2smbus *ps2smbus; + int error; + + ps2smbus = devm_kzalloc(&pdev->dev, sizeof(struct ps2smbus), + GFP_KERNEL); + if (!ps2smbus) + return -ENOMEM; + + ps2smbus->i2c_notifier.notifier_call = ps2smbus_notifier_call; + ps2smbus->pdata = pdev->dev.platform_data; + ps2smbus->type = pdev->id_entry->driver_data; + if (pdev->dev.parent) { + parent = to_serio_port(pdev->dev.parent); + if (ps2smbus->type == PS2SMBUS_SYNAPTICS_RMI4) + rmi_pdata->parent = parent; + } + + /* Keep track of adapters which will be added or removed later */ + error = bus_register_notifier(&i2c_bus_type, &ps2smbus->i2c_notifier); + if (error) + return error; + + /* Bind to already existing adapters right away */ + i2c_for_each_dev(ps2smbus, ps2smbus_attach_i2c_device); + + platform_set_drvdata(pdev, ps2smbus); + + return 0; +} + +static int ps2smbus_remove(struct platform_device *pdev) +{ + struct ps2smbus *ps2smbus = platform_get_drvdata(pdev); + + bus_unregister_notifier(&i2c_bus_type, &ps2smbus->i2c_notifier); + + if (ps2smbus->smbus_client) + ps2smbus_schedule_work(PS2SMBUS_UNREGISTER_DEVICE, ps2smbus, + NULL); + + platform_set_drvdata(pdev, NULL); + + return 0; +} + +static const struct platform_device_id ps2smbus_id_table[] = { + { .name = "rmi4", .driver_data = PS2SMBUS_SYNAPTICS_RMI4 }, + { } +}; +MODULE_DEVICE_TABLE(platform, ps2smbus_id_table); + +static struct platform_driver ps2smbus_drv = { + .driver = { + .name = "ps2smbus", + }, + .probe = ps2smbus_probe, + .remove = ps2smbus_remove, + .id_table = ps2smbus_id_table, +}; + +static int __init ps2smbus_init(void) +{ + int err; + + kps2smbus_wq = alloc_ordered_workqueue("kps2smbusd", WQ_MEM_RECLAIM); + if (!kps2smbus_wq) { + pr_err("failed to create kps2smbusd workqueue\n"); + return -ENOMEM; + } + + err = platform_driver_register(&ps2smbus_drv); + if (err) + destroy_workqueue(kps2smbus_wq); + + return err; +} + +static void __exit ps2smbus_exit(void) +{ + platform_driver_unregister(&ps2smbus_drv); + destroy_workqueue(kps2smbus_wq); +} + +module_init(ps2smbus_init); +module_exit(ps2smbus_exit); diff --git a/drivers/input/rmi4/Kconfig b/drivers/input/rmi4/Kconfig index 30cc627..eb74678 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. -- 2.9.3