diff --git a/drivers/char/ipmi/Kconfig b/drivers/char/ipmi/Kconfig index bc5f81899b629..249b31197eeae 100644 --- a/drivers/char/ipmi/Kconfig +++ b/drivers/char/ipmi/Kconfig @@ -137,6 +137,20 @@ config IPMI_KCS_BMC_CDEV_IPMI This support is also available as a module. The module will be called kcs_bmc_cdev_ipmi. +config IPMI_KCS_BMC_SERIO + depends on IPMI_KCS_BMC && SERIO + tristate "SerIO adaptor for BMC KCS devices" + help + Adapts the BMC KCS device for the SerIO subsystem. This allows users + to take advantage of userspace interfaces provided by SerIO where + appropriate. + + Say YES if you wish to expose KCS devices on the BMC via SerIO + interfaces. + + This support is also available as a module. The module will be + called kcs_bmc_serio. + config ASPEED_BT_IPMI_BMC depends on ARCH_ASPEED || COMPILE_TEST depends on REGMAP && REGMAP_MMIO && MFD_SYSCON diff --git a/drivers/char/ipmi/Makefile b/drivers/char/ipmi/Makefile index fcfa676afddbb..84f47d18007fb 100644 --- a/drivers/char/ipmi/Makefile +++ b/drivers/char/ipmi/Makefile @@ -23,6 +23,7 @@ obj-$(CONFIG_IPMI_POWERNV) += ipmi_powernv.o obj-$(CONFIG_IPMI_WATCHDOG) += ipmi_watchdog.o obj-$(CONFIG_IPMI_POWEROFF) += ipmi_poweroff.o obj-$(CONFIG_IPMI_KCS_BMC) += kcs_bmc.o +obj-$(CONFIG_IPMI_KCS_BMC_SERIO) += kcs_bmc_serio.o obj-$(CONFIG_IPMI_KCS_BMC_CDEV_IPMI) += kcs_bmc_cdev_ipmi.o obj-$(CONFIG_ASPEED_BT_IPMI_BMC) += bt-bmc.o obj-$(CONFIG_ASPEED_KCS_IPMI_BMC) += kcs_bmc_aspeed.o diff --git a/drivers/char/ipmi/kcs_bmc_serio.c b/drivers/char/ipmi/kcs_bmc_serio.c new file mode 100644 index 0000000000000..7948cabde50b4 --- /dev/null +++ b/drivers/char/ipmi/kcs_bmc_serio.c @@ -0,0 +1,157 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Copyright (c) 2021 IBM Corp. */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "kcs_bmc_client.h" + +struct kcs_bmc_serio { + struct list_head entry; + + struct kcs_bmc_client client; + struct serio *port; + + spinlock_t lock; +}; + +static inline struct kcs_bmc_serio *client_to_kcs_bmc_serio(struct kcs_bmc_client *client) +{ + return container_of(client, struct kcs_bmc_serio, client); +} + +static irqreturn_t kcs_bmc_serio_event(struct kcs_bmc_client *client) +{ + struct kcs_bmc_serio *priv; + u8 handled = IRQ_NONE; + u8 status; + + priv = client_to_kcs_bmc_serio(client); + + spin_lock(&priv->lock); + + status = kcs_bmc_read_status(client->dev); + + if (status & KCS_BMC_STR_IBF) + handled = serio_interrupt(priv->port, kcs_bmc_read_data(client->dev), 0); + + spin_unlock(&priv->lock); + + return handled; +} + +static const struct kcs_bmc_client_ops kcs_bmc_serio_client_ops = { + .event = kcs_bmc_serio_event, +}; + +static int kcs_bmc_serio_open(struct serio *port) +{ + struct kcs_bmc_serio *priv = port->port_data; + + return kcs_bmc_enable_device(priv->client.dev, &priv->client); +} + +static void kcs_bmc_serio_close(struct serio *port) +{ + struct kcs_bmc_serio *priv = port->port_data; + + kcs_bmc_disable_device(priv->client.dev, &priv->client); +} + +static DEFINE_SPINLOCK(kcs_bmc_serio_instances_lock); +static LIST_HEAD(kcs_bmc_serio_instances); + +static int kcs_bmc_serio_add_device(struct kcs_bmc_device *kcs_bmc) +{ + struct kcs_bmc_serio *priv; + struct serio *port; + + priv = devm_kzalloc(kcs_bmc->dev, sizeof(*priv), GFP_KERNEL); + + /* Use kzalloc() as the allocation is cleaned up with kfree() via serio_unregister_port() */ + port = kzalloc(sizeof(*port), GFP_KERNEL); + if (!(priv && port)) + return -ENOMEM; + + port->id.type = SERIO_8042; + port->open = kcs_bmc_serio_open; + port->close = kcs_bmc_serio_close; + port->port_data = priv; + port->dev.parent = kcs_bmc->dev; + + spin_lock_init(&priv->lock); + priv->port = port; + priv->client.dev = kcs_bmc; + priv->client.ops = &kcs_bmc_serio_client_ops; + + spin_lock_irq(&kcs_bmc_serio_instances_lock); + list_add(&priv->entry, &kcs_bmc_serio_instances); + spin_unlock_irq(&kcs_bmc_serio_instances_lock); + + serio_register_port(port); + + dev_info(kcs_bmc->dev, "Initialised serio client for channel %d", kcs_bmc->channel); + + return 0; +} + +static int kcs_bmc_serio_remove_device(struct kcs_bmc_device *kcs_bmc) +{ + struct kcs_bmc_serio *priv = NULL, *pos; + + spin_lock_irq(&kcs_bmc_serio_instances_lock); + list_for_each_entry(pos, &kcs_bmc_serio_instances, entry) { + if (pos->client.dev == kcs_bmc) { + priv = pos; + list_del(&pos->entry); + break; + } + } + spin_unlock_irq(&kcs_bmc_serio_instances_lock); + + if (!priv) + return -ENODEV; + + /* kfree()s priv->port via put_device() */ + serio_unregister_port(priv->port); + + /* Ensure the IBF IRQ is disabled if we were the active client */ + kcs_bmc_disable_device(kcs_bmc, &priv->client); + + devm_kfree(priv->client.dev->dev, priv); + + return 0; +} + +static const struct kcs_bmc_driver_ops kcs_bmc_serio_driver_ops = { + .add_device = kcs_bmc_serio_add_device, + .remove_device = kcs_bmc_serio_remove_device, +}; + +static struct kcs_bmc_driver kcs_bmc_serio_driver = { + .ops = &kcs_bmc_serio_driver_ops, +}; + +static int kcs_bmc_serio_init(void) +{ + kcs_bmc_register_driver(&kcs_bmc_serio_driver); + + return 0; +} +module_init(kcs_bmc_serio_init); + +static void kcs_bmc_serio_exit(void) +{ + kcs_bmc_unregister_driver(&kcs_bmc_serio_driver); +} +module_exit(kcs_bmc_serio_exit); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Andrew Jeffery "); +MODULE_DESCRIPTION("Adapter driver for serio access to BMC KCS devices");