M7350/kernel/drivers/misc/qpnp-misc.c
2024-09-09 08:52:07 +00:00

168 lines
4.2 KiB
C

/* Copyright (c) 2013, The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#define pr_fmt(fmt) "%s: " fmt, __func__
#include <linux/module.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/spmi.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/qpnp-misc.h>
#define QPNP_MISC_DEV_NAME "qcom,qpnp-misc"
#define REVID_REVISION2 0x1
static DEFINE_MUTEX(qpnp_misc_dev_list_mutex);
static LIST_HEAD(qpnp_misc_dev_list);
/**
* struct qpnp_misc_dev - holds controller device specific information
* @list: Doubly-linked list parameter linking to other
* qpnp_misc devices.
* @mutex: Mutex lock that is used to ensure mutual
* exclusion between probing and accessing misc
* driver information
* @dev: Device pointer to the misc device
* @resource: Resource pointer that holds base address
* @spmi: Spmi pointer which holds spmi information
*/
struct qpnp_misc_dev {
struct list_head list;
struct mutex mutex;
struct device *dev;
struct resource *resource;
struct spmi_device *spmi;
};
static struct of_device_id qpnp_misc_match_table[] = {
{ .compatible = QPNP_MISC_DEV_NAME },
{}
};
static u8 qpnp_read_byte(struct spmi_device *spmi, u16 addr)
{
int rc;
u8 val;
rc = spmi_ext_register_readl(spmi->ctrl, spmi->sid, addr, &val, 1);
if (rc) {
pr_err("SPMI read failed rc=%d\n", rc);
return 0;
}
return val;
}
#define REV2_IRQ_AVAILABLE_VERSION 2
static bool __misc_irqs_available(struct qpnp_misc_dev *dev)
{
u8 rev2;
rev2 = qpnp_read_byte(dev->spmi,
dev->resource->start + REVID_REVISION2);
pr_debug("rev2 0x%x\n", rev2);
if (rev2 >= REV2_IRQ_AVAILABLE_VERSION)
return 1;
return 0;
}
int qpnp_misc_irqs_available(struct device *consumer_dev)
{
struct device_node *misc_node = NULL;
struct qpnp_misc_dev *mdev = NULL;
struct qpnp_misc_dev *mdev_found = NULL;
misc_node = of_parse_phandle(consumer_dev->of_node, "qcom,misc-ref", 0);
if (!misc_node) {
pr_debug("Could not find qcom,misc-ref property in %s\n",
consumer_dev->of_node->full_name);
return 0;
}
mutex_lock(&qpnp_misc_dev_list_mutex);
list_for_each_entry(mdev, &qpnp_misc_dev_list, list) {
if (mdev->dev->of_node == misc_node) {
mdev_found = mdev;
break;
}
}
mutex_unlock(&qpnp_misc_dev_list_mutex);
if (!mdev_found) {
/* No MISC device was found. This API should only
* be called by drivers which have specified the
* misc phandle in their device tree node */
pr_err("no probed misc device found\n");
return -EPROBE_DEFER;
}
return __misc_irqs_available(mdev_found);
}
static int __devinit qpnp_misc_probe(struct spmi_device *spmi)
{
struct resource *resource;
struct qpnp_misc_dev *mdev = ERR_PTR(-EINVAL);
resource = spmi_get_resource(spmi, NULL, IORESOURCE_MEM, 0);
if (!resource) {
pr_err("Unable to get spmi resource for MISC\n");
return -EINVAL;
}
mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
if (!mdev) {
pr_err("allocation failed\n");
return -ENOMEM;
}
mdev->spmi = spmi;
mdev->dev = &(spmi->dev);
mdev->resource = resource;
mutex_lock(&qpnp_misc_dev_list_mutex);
list_add_tail(&mdev->list, &qpnp_misc_dev_list);
mutex_unlock(&qpnp_misc_dev_list_mutex);
pr_debug("probed successfully\n");
return 0;
}
static struct spmi_driver qpnp_misc_driver = {
.probe = qpnp_misc_probe,
.driver = {
.name = QPNP_MISC_DEV_NAME,
.owner = THIS_MODULE,
.of_match_table = qpnp_misc_match_table,
},
};
static int __init qpnp_misc_init(void)
{
return spmi_driver_register(&qpnp_misc_driver);
}
static void __exit qpnp_misc_exit(void)
{
return spmi_driver_unregister(&qpnp_misc_driver);
}
module_init(qpnp_misc_init);
module_exit(qpnp_misc_exit);
MODULE_DESCRIPTION(QPNP_MISC_DEV_NAME);
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:" QPNP_MISC_DEV_NAME);