marvell/linux/drivers/crypto/asr/asr_aes_clk.c

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/clk-provider.h>
#include <linux/clk.h>
#include <linux/mutex.h>

struct asr_crypto {
	struct clk *aes_clk;
	refcount_t	refcount;
	struct mutex clk_lock;
};

static struct asr_crypto asr_crypto = {
	.aes_clk = 0,
	.refcount = REFCOUNT_INIT(0),
	.clk_lock = __MUTEX_INITIALIZER(asr_crypto.clk_lock),
};

int asr_aes_clk_get(struct clk *aes_clk)
{
	mutex_lock(&asr_crypto.clk_lock);

	if (asr_crypto.aes_clk != aes_clk) {
		asr_crypto.aes_clk = aes_clk;
	}

	if (refcount_read(&asr_crypto.refcount) == 0) {
		clk_enable(asr_crypto.aes_clk);
		refcount_set(&asr_crypto.refcount, 1);
	} else {
		refcount_inc(&asr_crypto.refcount);
	}

	mutex_unlock(&asr_crypto.clk_lock);
	return 0;
}
EXPORT_SYMBOL_GPL(asr_aes_clk_get);

int asr_aes_clk_put(struct clk *aes_clk)
{
	mutex_lock(&asr_crypto.clk_lock);

	if (refcount_dec_and_test(&asr_crypto.refcount)) {
		clk_disable(asr_crypto.aes_clk);
	}

	mutex_unlock(&asr_crypto.clk_lock);
	return 0;
}

EXPORT_SYMBOL_GPL(asr_aes_clk_put);