path: root/drivers/input/rmi4/rmi_driver.c

/*
 * Copyright (c) 2011-2016 Synaptics Incorporated
 * Copyright (c) 2011 Unixphere
 *
 * This driver provides the core support for a single RMI4-based device.
 *
 * The RMI4 specification can be found here (URL split for line length):
 *
 * http://www.synaptics.com/sites/default/files/
 *      511-000136-01-Rev-E-RMI4-Interfacing-Guide.pdf
 *
 * 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/bitmap.h>
#include <linux/delay.h>
#include <linux/fs.h>
#include <linux/kconfig.h>
#include <linux/pm.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <uapi/linux/input.h>
#include <linux/rmi.h>
#include "rmi_bus.h"
#include "rmi_driver.h"

#define HAS_NONSTANDARD_PDT_MASK 0x40
#define RMI4_MAX_PAGE 0xff
#define RMI4_PAGE_SIZE 0x100
#define RMI4_PAGE_MASK 0xFF00

#define RMI_DEVICE_RESET_CMD	0x01
#define DEFAULT_RESET_DELAY_MS	100

static void rmi_free_function_list(struct rmi_device *rmi_dev)
{
	struct rmi_function *fn, *tmp;
	struct rmi_driver_data *data = dev_get_drvdata(&rmi_dev->dev);

	data->f01_container = NULL;

	/* Doing it in the reverse order so F01 will be removed last */
	list_for_each_entry_safe_reverse(fn, tmp,
					 &data->function_list, node) {
		list_del(&fn->node);
		rmi_unregister_function(fn);
	}
}

static int reset_one_function(struct rmi_function *fn)
{
	struct rmi_function_handler *fh;
	int retval = 0;

	if (!fn || !fn->dev.driver)
		return 0;

	fh = to_rmi_function_handler(fn->dev.driver);
	if (fh->reset) {
		retval = fh->reset(fn);
		if (retval < 0)
			dev_err(&fn->dev, "Reset failed with code %d.\n",
				retval);
	}

	return retval;
}

static int configure_one_function(struct rmi_function *fn)
{
	struct rmi_function_handler *fh;
	int retval = 0;

	if (!fn || !fn->dev.driver)
		return 0;

	fh = to_rmi_function_handler(fn->dev.driver);
	if (fh->config) {
		retval = fh->config(fn);
		if (retval < 0)
			dev_err(&fn->dev, "Config failed with code %d.\n",
				retval);
	}

	return retval;
}

static int rmi_driver_process_reset_requests(struct rmi_device *rmi_dev)
{
	struct rmi_driver_data *data = dev_get_drvdata(&rmi_dev->dev);
	struct rmi_function *entry;
	int retval;

	list_for_each_entry(entry, &data->function_list, node) {
		retval = reset_one_function(entry);
		if (retval < 0)
			return retval;
	}

	return 0;
}

static int rmi_driver_process_config_requests(struct rmi_device *rmi_dev)
{
	struct rmi_driver_data *data = dev_get_drvdata(&rmi_dev->dev);
	struct rmi_function *entry;
	int retval;

	list_for_each_entry(entry, &data->function_list, node) {
		retval = configure_one_function(entry);
		if (retval < 0)
			return retval;
	}

	return 0;
}

static void process_one_interrupt(struct rmi_driver_data *data,
				  struct rmi_function *fn)
{
	struct rmi_function_handler *fh;

	if (!fn || !fn->dev.driver)
		return;

	fh = to_rmi_function_handler(fn->dev.driver);
	if (fh->attention) {
		bitmap_and(data->fn_irq_bits, data->irq_status, fn->irq_mask,
				data->irq_count);
		if (!bitmap_empty(data->fn_irq_bits, data->irq_count))
			fh->attention(fn, data->fn_irq_bits);
	}
}

int rmi_process_interrupt_requests(struct rmi_device *rmi_dev)
{
	struct rmi_driver_data *data = dev_get_drvdata(&rmi_dev->dev);
	struct device *dev = &rmi_dev->dev;
	struct rmi_function *entry;
	int error;

	if (!data)
		return 0;

	if (!rmi_dev->xport->attn_data) {
		error = rmi_read_block(rmi_dev,
				data->f01_container->fd.data_base_addr + 1,
				data->irq_status, data->num_of_irq_regs);
		if (error < 0) {
			dev_err(dev, "Failed to read irqs, code=%d\n", error);
			return error;
		}
	}

	mutex_lock(&data->irq_mutex);
	bitmap_and(data->irq_status, data->irq_status, data->current_irq_mask,
	       data->irq_count);
	/*
	 * At this point, irq_status has all bits that are set in the
	 * interrupt status register and are enabled.
	 */
	mutex_unlock(&data->irq_mutex);

	/*
	 * It would be nice to be able to use irq_chip to handle these
	 * nested IRQs.  Unfortunately, most of the current customers for
	 * this driver are using older kernels (3.0.x) that don't support
	 * the features required for that.  Once they've shifted to more
	 * recent kernels (say, 3.3 and higher), this should be switched to
	 * use irq_chip.
	 */
	list_for_each_entry(entry, &data->function_list, node)
		process_one_interrupt(data, entry);

	if (data->input)
		input_sync(data->input);

	return