diff options
Diffstat (limited to 'drivers/input/rmi4/rmi_bus.c')
-rw-r--r-- | drivers/input/rmi4/rmi_bus.c | 419 |
1 files changed, 419 insertions, 0 deletions
diff --git a/drivers/input/rmi4/rmi_bus.c b/drivers/input/rmi4/rmi_bus.c new file mode 100644 index 000000000000..b368b0515c5a --- /dev/null +++ b/drivers/input/rmi4/rmi_bus.c @@ -0,0 +1,419 @@ +/* + * Copyright (c) 2011-2016 Synaptics Incorporated + * Copyright (c) 2011 Unixphere + * + * 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 <linux/kernel.h> +#include <linux/device.h> +#include <linux/kconfig.h> +#include <linux/list.h> +#include <linux/pm.h> +#include <linux/rmi.h> +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/of.h> +#include "rmi_bus.h" +#include "rmi_driver.h" + +static int debug_flags; +module_param(debug_flags, int, 0644); +MODULE_PARM_DESC(debug_flags, "control debugging information"); + +void rmi_dbg(int flags, struct device *dev, const char *fmt, ...) +{ + struct va_format vaf; + va_list args; + + if (flags & debug_flags) { + va_start(args, fmt); + + vaf.fmt = fmt; + vaf.va = &args; + + dev_printk(KERN_DEBUG, dev, "%pV", &vaf); + + va_end(args); + } +} +EXPORT_SYMBOL_GPL(rmi_dbg); + +/* + * RMI Physical devices + * + * Physical RMI device consists of several functions serving particular + * purpose. For example F11 is a 2D touch sensor while F01 is a generic + * function present in every RMI device. + */ + +static void rmi_release_device(struct device *dev) +{ + struct rmi_device *rmi_dev = to_rmi_device(dev); + + kfree(rmi_dev); +} + +static struct device_type rmi_device_type = { + .name = "rmi4_sensor", + .release = rmi_release_device, +}; + +bool rmi_is_physical_device(struct device *dev) +{ + return dev->type == &rmi_device_type; +} + +/** + * rmi_register_transport_device - register a transport device connection + * on the RMI bus. Transport drivers provide communication from the devices + * on a bus (such as SPI, I2C, and so on) to the RMI4 sensor. + * + * @xport: the transport device to register + */ +int rmi_register_transport_device(struct rmi_transport_dev *xport) +{ + static atomic_t transport_device_count = ATOMIC_INIT(0); + struct rmi_device *rmi_dev; + int error; + + rmi_dev = kzalloc(sizeof(struct rmi_device), GFP_KERNEL); + if (!rmi_dev) + return -ENOMEM; + + device_initialize(&rmi_dev->dev); + + rmi_dev->xport = xport; + rmi_dev->number = atomic_inc_return(&transport_device_count) - 1; + + dev_set_name(&rmi_dev->dev, "rmi4-%02d", rmi_dev->number); + + rmi_dev->dev.bus = &rmi_bus_type; + rmi_dev->dev.type = &rmi_device_type; + + xport->rmi_dev = rmi_dev; + + error = device_add(&rmi_dev->dev); + if (error) + goto err_put_device; + + rmi_dbg(RMI_DEBUG_CORE, xport->dev, + "%s: Registered %s as %s.\n", __func__, + dev_name(rmi_dev->xport->dev), dev_name(&rmi_dev->dev)); + + return 0; + +err_put_device: + put_device(&rmi_dev->dev); + return error; +} +EXPORT_SYMBOL_GPL(rmi_register_transport_device); + +/** + * rmi_unregister_transport_device - unregister a transport device connection + * @xport: the transport driver to unregister + * + */ +void rmi_unregister_transport_device(struct rmi_transport_dev *xport) +{ + struct rmi_device *rmi_dev = xport->rmi_dev; + + device_del(&rmi_dev->dev); + put_device(&rmi_dev->dev); +} +EXPORT_SYMBOL(rmi_unregister_transport_device); + + +/* Function specific stuff */ + +static void rmi_release_function(struct device *dev) +{ + struct rmi_function *fn = to_rmi_function(dev); + + kfree(fn); +} + +static struct device_type rmi_function_type = { + .name = "rmi4_function", + .release = rmi_release_function, +}; + +bool rmi_is_function_device(struct device *dev) +{ + return dev->type == &rmi_function_type; +} + +static int rmi_function_match(struct device *dev, struct device_driver *drv) +{ + struct rmi_function_handler *handler = to_rmi_function_handler(drv); + struct rmi_function *fn = to_rmi_function(dev); + + return fn->fd.function_number == handler->func; +} + +#ifdef CONFIG_OF +static void rmi_function_of_probe(struct rmi_function *fn) +{ + char of_name[9]; + + snprintf(of_name, sizeof(of_name), "rmi4-f%02x", + fn->fd.function_number); + fn->dev.of_node = of_find_node_by_name( + fn->rmi_dev->xport->dev->of_node, of_name); +} +#else +static inline void rmi_function_of_probe(struct rmi_function *fn) +{} +#endif + +static int rmi_function_probe(struct device *dev) +{ + struct rmi_function *fn = to_rmi_function(dev); + struct rmi_function_handler *handler = + to_rmi_function_handler(dev->driver); + int error; + + rmi_function_of_probe(fn); + + if (handler->probe) { + error = handler->probe(fn); + return error; + } + + return 0; +} + +static int rmi_function_remove(struct device *dev) +{ + struct rmi_function *fn = to_rmi_function(dev); + struct rmi_function_handler *handler = + to_rmi_function_handler(dev->driver); + + if (handler->remove) + handler->remove(fn); + + return 0; +} + +int rmi_register_function(struct rmi_function *fn) +{ + struct rmi_device *rmi_dev = fn->rmi_dev; + int error; + + device_initialize(&fn->dev); + + dev_set_name(&fn->dev, "%s.fn%02x", + dev_name(&rmi_dev->dev), fn->fd.function_number); + + fn->dev.parent = &rmi_dev->dev; + fn->dev.type = &rmi_function_type; + fn->dev.bus = &rmi_bus_type; + + error = device_add(&fn->dev); + if (error) { + dev_err(&rmi_dev->dev, + "Failed device_register function device %s\n", + dev_name(&fn->dev)); + goto err_put_device; + } + + rmi_dbg(RMI_DEBUG_CORE, &rmi_dev->dev, "Registered F%02X.\n", + fn->fd.function_number); + + return 0; + +err_put_device: + put_device(&fn->dev); + return error; +} + +void rmi_unregister_function(struct rmi_function *fn) +{ + device_del(&fn->dev); + + if (fn->dev.of_node) + of_node_put(fn->dev.of_node); + + put_device(&fn->dev); +} + +/** + * rmi_register_function_handler - register a handler for an RMI function + * @handler: RMI handler that should be registered. + * @module: pointer to module that implements the handler + * @mod_name: name of the module implementing the handler + * + * This function performs additional setup of RMI function handler and + * registers it with the RMI core so that it can be bound to + * RMI function devices. + */ +int __rmi_register_function_handler(struct rmi_function_handler *handler, + struct module *owner, + const char *mod_name) +{ + struct device_driver *driver = &handler->driver; + int error; + + driver->bus = &rmi_bus_type; + driver->owner = owner; + driver->mod_name = mod_name; + driver->probe = rmi_function_probe; + driver->remove = rmi_function_remove; + + error = driver_register(&handler->driver); + if (error) { + pr_err("driver_register() failed for %s, error: %d\n", + handler->driver.name, error); + return error; + } + + return 0; +} +EXPORT_SYMBOL_GPL(__rmi_register_function_handler); + +/** + * rmi_unregister_function_handler - unregister given RMI function handler + * @handler: RMI handler that should be unregistered. + * + * This function unregisters given function handler from RMI core which + * causes it to be unbound from the function devices. + */ +void rmi_unregister_function_handler(struct rmi_function_handler *handler) +{ + driver_unregister(&handler->driver); +} +EXPORT_SYMBOL_GPL(rmi_unregister_function_handler); + +/* Bus specific stuff */ + +static int rmi_bus_match(struct device *dev, struct device_driver *drv) +{ + bool physical = rmi_is_physical_device(dev); + + /* First see if types are not compatible */ + if (physical != rmi_is_physical_driver(drv)) + return 0; + + return physical || rmi_function_match(dev, drv); +} + +struct bus_type rmi_bus_type = { + .match = rmi_bus_match, + .name = "rmi4", +}; + +static struct rmi_function_handler *fn_handlers[] = { + &rmi_f01_handler, +#ifdef CONFIG_RMI4_F11 + &rmi_f11_handler, +#endif +#ifdef CONFIG_RMI4_F12 + &rmi_f12_handler, +#endif +#ifdef CONFIG_RMI4_F30 + &rmi_f30_handler, +#endif +}; + +static void __rmi_unregister_function_handlers(int start_idx) +{ + int i; + + for (i = start_idx; i >= 0; i--) + rmi_unregister_function_handler(fn_handlers[i]); +} + +static void rmi_unregister_function_handlers(void) +{ + __rmi_unregister_function_handlers(ARRAY_SIZE(fn_handlers) - 1); +} + +static int rmi_register_function_handlers(void) +{ + int ret; + int i; + + for (i = 0; i < ARRAY_SIZE(fn_handlers); i++) { + ret = rmi_register_function_handler(fn_handlers[i]); + if (ret) { + pr_err("%s: error registering the RMI F%02x handler: %d\n", + __func__, fn_handlers[i]->func, ret); + goto err_unregister_function_handlers; + } + } + + return 0; + +err_unregister_function_handlers: + __rmi_unregister_function_handlers(i - 1); + return ret; +} + +int rmi_of_property_read_u32(struct device *dev, u32 *result, + const char *prop, bool optional) +{ + int retval; + u32 val = 0; + + retval = of_property_read_u32(dev->of_node, prop, &val); + if (retval && (!optional && retval == -EINVAL)) { + dev_err(dev, "Failed to get %s value: %d\n", + prop, retval); + return retval; + } + *result = val; + + return 0; +} +EXPORT_SYMBOL_GPL(rmi_of_property_read_u32); + +static int __init rmi_bus_init(void) +{ + int error; + + error = bus_register(&rmi_bus_type); + if (error) { + pr_err("%s: error registering the RMI bus: %d\n", + __func__, error); + return error; + } + + error = rmi_register_function_handlers(); + if (error) + goto err_unregister_bus; + + error = rmi_register_physical_driver(); + if (error) { + pr_err("%s: error registering the RMI physical driver: %d\n", + __func__, error); + goto err_unregister_bus; + } + + return 0; + +err_unregister_bus: + bus_unregister(&rmi_bus_type); + return error; +} +module_init(rmi_bus_init); + +static void __exit rmi_bus_exit(void) +{ + /* + * We should only ever get here if all drivers are unloaded, so + * all we have to do at this point is unregister ourselves. + */ + + rmi_unregister_physical_driver(); + rmi_unregister_function_handlers(); + bus_unregister(&rmi_bus_type); +} +module_exit(rmi_bus_exit); + +MODULE_AUTHOR("Christopher Heiny <cheiny@synaptics.com"); +MODULE_AUTHOR("Andrew Duggan <aduggan@synaptics.com"); +MODULE_DESCRIPTION("RMI bus"); +MODULE_LICENSE("GPL"); +MODULE_VERSION(RMI_DRIVER_VERSION); |