// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Generic pwmlib implementation
*
* Copyright (C) 2011 Sascha Hauer <s.hauer@pengutronix.de>
* Copyright (C) 2011-2012 Avionic Design GmbH
*/
#include <linux/acpi.h>
#include <linux/module.h>
#include <linux/pwm.h>
#include <linux/radix-tree.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <dt-bindings/pwm/pwm.h>
#define CREATE_TRACE_POINTS
#include <trace/events/pwm.h>
#define MAX_PWMS 1024
static DEFINE_MUTEX(pwm_lookup_lock);
static LIST_HEAD(pwm_lookup_list);
static DEFINE_MUTEX(pwm_lock);
static LIST_HEAD(pwm_chips);
static DECLARE_BITMAP(allocated_pwms, MAX_PWMS);
static RADIX_TREE(pwm_tree, GFP_KERNEL);
static struct pwm_device *pwm_to_device(unsigned int pwm)
{
return radix_tree_lookup(&pwm_tree, pwm);
}
static int alloc_pwms(int pwm, unsigned int count)
{
unsigned int from = 0;
unsigned int start;
if (pwm >= MAX_PWMS)
return -EINVAL;
if (pwm >= 0)
from = pwm;
start = bitmap_find_next_zero_area(allocated_pwms, MAX_PWMS, from,
count, 0);
if (pwm >= 0 && start != pwm)
return -EEXIST;
if (start + count > MAX_PWMS)
return -ENOSPC;
return start;
}
static void free_pwms(struct pwm_chip *chip)
{
unsigned int i;
for (i = 0; i < chip->npwm; i++) {
struct pwm_device *pwm = &chip->pwms[i];
radix_tree_delete(&pwm_tree, pwm->pwm);
}
bitmap_clear(allocated_pwms, chip->base, chip->npwm);
kfree(chip->pwms);
chip->pwms = NULL;
}
static struct pwm_chip *pwmchip_find_by_name(const char *name)
{
struct pwm_chip *chip;
if (!name)
return NULL;
mutex_lock(&pwm_lock);
list_for_each_entry(chip, &pwm_chips, list) {
const char *chip_name = dev_name(chip->dev);
if (chip_name && strcmp(chip_name, name) == 0) {
mutex_unlock(&pwm_lock);
return chip;
}
}
mutex_unlock(&pwm_lock);
return NULL;
}
static int pwm_device_request(struct pwm_device *pwm, const char *label)
{
int err;
if (test_bit(PWMF_REQUESTED,