root/drivers/clk/clk-bulk.c
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright 2017 NXP
 *
 * Dong Aisheng <aisheng.dong@nxp.com>
 */

#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/device.h>
#include <linux/export.h>
#include <linux/of.h>
#include <linux/slab.h>

static int __must_check of_clk_bulk_get(struct device_node *np, int num_clks,
                                        struct clk_bulk_data *clks)
{
        int ret;
        int i;

        for (i = 0; i < num_clks; i++) {
                clks[i].id = NULL;
                clks[i].clk = NULL;
        }

        for (i = 0; i < num_clks; i++) {
                of_property_read_string_index(np, "clock-names", i, &clks[i].id);
                clks[i].clk = of_clk_get(np, i);
                if (IS_ERR(clks[i].clk)) {
                        ret = PTR_ERR(clks[i].clk);
                        pr_err("%pOF: Failed to get clk index: %d ret: %d\n",
                               np, i, ret);
                        clks[i].clk = NULL;
                        goto err;
                }
        }

        return 0;

err:
        clk_bulk_put(i, clks);

        return ret;
}

static int __must_check of_clk_bulk_get_all(struct device_node *np,
                                            struct clk_bulk_data **clks)
{
        struct clk_bulk_data *clk_bulk;
        int num_clks;
        int ret;

        num_clks = of_clk_get_parent_count(np);
        if (!num_clks)
                return 0;

        clk_bulk = kmalloc_objs(*clk_bulk, num_clks);
        if (!clk_bulk)
                return -ENOMEM;

        ret = of_clk_bulk_get(np, num_clks, clk_bulk);
        if (ret) {
                kfree(clk_bulk);
                return ret;
        }

        *clks = clk_bulk;

        return num_clks;
}

void clk_bulk_put(int num_clks, struct clk_bulk_data *clks)
{
        while (--num_clks >= 0) {
                clk_put(clks[num_clks].clk);
                clks[num_clks].clk = NULL;
        }
}
EXPORT_SYMBOL_GPL(clk_bulk_put);

static int __clk_bulk_get(struct device *dev, int num_clks,
                          struct clk_bulk_data *clks, bool optional)
{
        int ret;
        int i;

        for (i = 0; i < num_clks; i++)
                clks[i].clk = NULL;

        for (i = 0; i < num_clks; i++) {
                clks[i].clk = clk_get(dev, clks[i].id);
                if (IS_ERR(clks[i].clk)) {
                        ret = PTR_ERR(clks[i].clk);
                        clks[i].clk = NULL;

                        if (ret == -ENOENT && optional)
                                continue;

                        dev_err_probe(dev, ret,
                                      "Failed to get clk '%s'\n",
                                      clks[i].id);
                        goto err;
                }
        }

        return 0;

err:
        clk_bulk_put(i, clks);

        return ret;
}

int __must_check clk_bulk_get(struct device *dev, int num_clks,
                              struct clk_bulk_data *clks)
{
        return __clk_bulk_get(dev, num_clks, clks, false);
}
EXPORT_SYMBOL(clk_bulk_get);

int __must_check clk_bulk_get_optional(struct device *dev, int num_clks,
                                       struct clk_bulk_data *clks)
{
        return __clk_bulk_get(dev, num_clks, clks, true);
}
EXPORT_SYMBOL_GPL(clk_bulk_get_optional);

void clk_bulk_put_all(int num_clks, struct clk_bulk_data *clks)
{
        if (IS_ERR_OR_NULL(clks))
                return;

        clk_bulk_put(num_clks, clks);

        kfree(clks);
}
EXPORT_SYMBOL(clk_bulk_put_all);

int __must_check clk_bulk_get_all(struct device *dev,
                                  struct clk_bulk_data **clks)
{
        struct device_node *np = dev_of_node(dev);

        if (!np)
                return 0;

        return of_clk_bulk_get_all(np, clks);
}
EXPORT_SYMBOL(clk_bulk_get_all);

#ifdef CONFIG_HAVE_CLK_PREPARE

/**
 * clk_bulk_unprepare - undo preparation of a set of clock sources
 * @num_clks: the number of clk_bulk_data
 * @clks: the clk_bulk_data table being unprepared
 *
 * clk_bulk_unprepare may sleep, which differentiates it from clk_bulk_disable.
 * Returns 0 on success, -EERROR otherwise.
 */
void clk_bulk_unprepare(int num_clks, const struct clk_bulk_data *clks)
{
        while (--num_clks >= 0)
                clk_unprepare(clks[num_clks].clk);
}
EXPORT_SYMBOL_GPL(clk_bulk_unprepare);

/**
 * clk_bulk_prepare - prepare a set of clocks
 * @num_clks: the number of clk_bulk_data
 * @clks: the clk_bulk_data table being prepared
 *
 * clk_bulk_prepare may sleep, which differentiates it from clk_bulk_enable.
 * Returns 0 on success, -EERROR otherwise.
 */
int __must_check clk_bulk_prepare(int num_clks,
                                  const struct clk_bulk_data *clks)
{
        int ret;
        int i;

        for (i = 0; i < num_clks; i++) {
                ret = clk_prepare(clks[i].clk);
                if (ret) {
                        pr_err("Failed to prepare clk '%s': %d\n",
                                clks[i].id, ret);
                        goto err;
                }
        }

        return 0;

err:
        clk_bulk_unprepare(i, clks);

        return  ret;
}
EXPORT_SYMBOL_GPL(clk_bulk_prepare);

#endif /* CONFIG_HAVE_CLK_PREPARE */

/**
 * clk_bulk_disable - gate a set of clocks
 * @num_clks: the number of clk_bulk_data
 * @clks: the clk_bulk_data table being gated
 *
 * clk_bulk_disable must not sleep, which differentiates it from
 * clk_bulk_unprepare. clk_bulk_disable must be called before
 * clk_bulk_unprepare.
 */
void clk_bulk_disable(int num_clks, const struct clk_bulk_data *clks)
{

        while (--num_clks >= 0)
                clk_disable(clks[num_clks].clk);
}
EXPORT_SYMBOL_GPL(clk_bulk_disable);

/**
 * clk_bulk_enable - ungate a set of clocks
 * @num_clks: the number of clk_bulk_data
 * @clks: the clk_bulk_data table being ungated
 *
 * clk_bulk_enable must not sleep
 * Returns 0 on success, -EERROR otherwise.
 */
int __must_check clk_bulk_enable(int num_clks, const struct clk_bulk_data *clks)
{
        int ret;
        int i;

        for (i = 0; i < num_clks; i++) {
                ret = clk_enable(clks[i].clk);
                if (ret) {
                        pr_err("Failed to enable clk '%s': %d\n",
                                clks[i].id, ret);
                        goto err;
                }
        }

        return 0;

err:
        clk_bulk_disable(i, clks);

        return  ret;
}
EXPORT_SYMBOL_GPL(clk_bulk_enable);