1 files changed, 478 insertions, 0 deletions
diff --git a/drivers/input/rmi4/rmi_bus.c b/drivers/input/rmi4/rmi_bus.c
new file mode 100644
index 0000000000..1b45b1d307
--- /dev/null
+++ b/drivers/input/rmi4/rmi_bus.c
@@ -0,0 +1,478 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2011-2016 Synaptics Incorporated
+ * Copyright (c) 2011 Unixphere
+ */
+
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.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 const 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;
+	rmi_dev->dev.parent = xport->dev;
+
+	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 const 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];
+	struct device_node *node = fn->rmi_dev->xport->dev->of_node;
+
+	snprintf(of_name, sizeof(of_name), "rmi4-f%02x",
+		fn->fd.function_number);
+	fn->dev.of_node = of_get_child_by_name(node, of_name);
+}
+#else
+static inline void rmi_function_of_probe(struct rmi_function *fn)
+{}
+#endif
+
+static struct irq_chip rmi_irq_chip = {
+	.name = "rmi4",
+};
+
+static int rmi_create_function_irq(struct rmi_function *fn,
+				   struct rmi_function_handler *handler)
+{
+	struct rmi_driver_data *drvdata = dev_get_drvdata(&fn->rmi_dev->dev);
+	int i, error;
+
+	for (i = 0; i < fn->num_of_irqs; i++) {
+		set_bit(fn->irq_pos + i, fn->irq_mask);
+
+		fn->irq[i] = irq_create_mapping(drvdata->irqdomain,
+						fn->irq_pos + i);
+
+		irq_set_chip_data(fn->irq[i], fn);
+		irq_set_chip_and_handler(fn->irq[i], &rmi_irq_chip,
+					 handle_simple_irq);
+		irq_set_nested_thread(fn->irq[i], 1);
+
+		error = devm_request_threaded_irq(&fn->dev, fn->irq[i], NULL,
+					handler->attention, IRQF_ONESHOT,
+					dev_name(&fn->dev), fn);
+		if (error) {
+			dev_err(&fn->dev, "Error %d registering IRQ\n", error);
+			return error;
+		}
+	}
+
+	return 0;
+}
+
+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);
+		if (error)
+			return error;
+	}
+
+	if (fn->num_of_irqs && handler->attention) {
+		error = rmi_create_function_irq(fn, handler);
+		if (error)
+			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)
+{
+	int i;
+
+	rmi_dbg(RMI_DEBUG_CORE, &fn->dev, "Unregistering F%02X.\n",
+			fn->fd.function_number);
+
+	device_del(&fn->dev);
+	of_node_put(fn->dev.of_node);
+
+	for (i = 0; i < fn->num_of_irqs; i++)
+		irq_dispose_mapping(fn->irq[i]);
+
+	put_device(&fn->dev);
+}
+
+/**
+ * __rmi_register_function_handler - register a handler for an RMI function
+ * @handler: RMI handler that should be registered.
+ * @owner: 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(driver);
+	if (error) {
+		pr_err("driver_register() failed for %s, error: %d\n",
+			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_F03
+	&rmi_f03_handler,
+#endif
+#ifdef CONFIG_RMI4_F11
+	&rmi_f11_handler,
+#endif
+#ifdef CONFIG_RMI4_F12
+	&rmi_f12_handler,
+#endif
+#ifdef CONFIG_RMI4_F30
+	&rmi_f30_handler,
+#endif
+#ifdef CONFIG_RMI4_F34
+	&rmi_f34_handler,
+#endif
+#ifdef CONFIG_RMI4_F3A
+	&rmi_f3a_handler,
+#endif
+#ifdef CONFIG_RMI4_F54
+	&rmi_f54_handler,
+#endif
+#ifdef CONFIG_RMI4_F55
+	&rmi_f55_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");