/* * Cryptographic API. * * Support for Samsung S5PV210 HW acceleration. * * Copyright (C) 2011 NetUP Inc. 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 as published * by the Free Software Foundation. * */ #include <linux/delay.h> #include <linux/err.h> #include <linux/module.h> #include <linux/init.h> #include <linux/errno.h> #include <linux/kernel.h> #include <linux/clk.h> #include <linux/platform_device.h> #include <linux/scatterlist.h> #include <linux/dma-mapping.h> #include <linux/io.h> #include <linux/of.h> #include <linux/crypto.h> #include <linux/interrupt.h> #include <crypto/algapi.h> #include <crypto/aes.h> #include <crypto/ctr.h> #define _SBF(s, v) ((v) << (s)) #define _BIT(b) _SBF(b, 1) /* Feed control registers */ #define SSS_REG_FCINTSTAT 0x0000 #define SSS_FCINTSTAT_BRDMAINT _BIT(3) #define SSS_FCINTSTAT_BTDMAINT _BIT(2) #define SSS_FCINTSTAT_HRDMAINT _BIT(1) #define SSS_FCINTSTAT_PKDMAINT _BIT(0) #define SSS_REG_FCINTENSET 0x0004 #define SSS_FCINTENSET_BRDMAINTENSET _BIT(3) #define SSS_FCINTENSET_BTDMAINTENSET _BIT(2) #define SSS_FCINTENSET_HRDMAINTENSET _BIT(1) #define SSS_FCINTENSET_PKDMAINTENSET _BIT(0) #define SSS_REG_FCINTENCLR 0x0008 #define SSS_FCINTENCLR_BRDMAINTENCLR _BIT(3) #define SSS_FCINTENCLR_BTDMAINTENCLR _BIT(2) #define SSS_FCINTENCLR_HRDMAINTENCLR _BIT(1) #define SSS_FCINTENCLR_PKDMAINTENCLR _BIT(0) #define SSS_REG_FCINTPEND 0x000C #define SSS_FCINTPEND_BRDMAINTP _BIT(3) #define SSS_FCINTPEND_BTDMAINTP _BIT(2) #define SSS_FCINTPEND_HRDMAINTP _BIT(1) #define SSS_FCINTPEND_PKDMAINTP _BIT(0) #define SSS_REG_FCFIFOSTAT 0x0010 #define SSS_FCFIFOSTAT_BRFIFOFUL _BIT(7) #define SSS_FCFIFOSTAT_BRFIFOEMP _BIT(6) #define SSS_FCFIFOSTAT_BTFIFOFUL _BIT(5) #define SSS_FCFIFOSTAT_BTFIFOEMP _BIT(4) #define SSS_FCFIFOSTAT_HRFIFOFUL _BIT(3) #define SSS_FCFIFOSTAT_HRFIFOEMP _BIT(2) #define SSS_FCFIFOSTAT_PKFIFOFUL _BIT(1) #define SSS_FCFIFOSTAT_PKFIFOEMP _BIT(0) #define SSS_REG_FCFIFOCTRL 0x0014 #define SSS_FCFIFOCTRL_DESSEL _BIT(2) #define SSS_HASHIN_INDEPENDENT _SBF(0, 0x00) #define SSS_HASHIN_CIPHER_INPUT _SBF(0, 0x01) #define SSS_HASHIN_CIPHER_OUTPUT _SBF(0, 0x02) #define SSS_REG_FCBRDMAS 0x0020 #define SSS_REG_FCBRDMAL 0x0024 #define SSS_REG_FCBRDMAC 0x0028 #define SSS_FCBRDMAC_BYTESWAP _BIT(1) #define SSS_FCBRDMAC_FLUSH _BIT(0) #define SSS_REG_FCBTDMAS 0x0030 #define SSS_REG_FCBTDMAL 0x0034 #define SSS_REG_FCBTDMAC 0x0038 #define SSS_FCBTDMAC_BYTESWAP _BIT(1) #define SSS_FCBTDMAC_FLUSH _BIT(0) #define SSS_REG_FCHRDMAS 0x0040 #define SSS_REG_FCHRDMAL 0x0044 #define SSS_REG_FCHRDMAC 0x0048 #define SSS_FCHRDMAC_BYTESWAP _BIT(1) #define SSS_FCHRDMAC_FLUSH _BIT(0) #define SSS_REG_FCPKDMAS 0x0050 #define SSS_REG_FCPKDMAL 0x0054 #define SSS_REG_FCPKDMAC 0x0058 #define SSS_FCPKDMAC_BYTESWAP _BIT(3) #define SSS_FCPKDMAC_DESCEND _BIT(2) #define SSS_FCPKDMAC_TRANSMIT _BIT(1) #define SSS_FCPKDMAC_FLUSH _BIT(0) #define SSS_REG_FCPKDMAO 0x005C /* AES registers */ #define SSS_REG_AES_CONTROL 0x00 #define SSS_AES_BYTESWAP_DI _BIT(11) #define SSS_AES_BYTESWAP_DO _BIT(10) #define SSS_AES_BYTESWAP_IV _BIT(9) #define SSS_AES_BYTESWAP_CNT _BIT(8) #define SSS_AES_BYTESWAP_KEY _BIT(7) #define SSS_AES_KEY_CHANGE_MODE _BIT(6) #define SSS_AES_KEY_SIZE_128 _SBF(4, 0x00) #define SSS_AES_KEY_SIZE_192 _SBF(4, 0x01) #define SSS_AES_KEY_SIZE_256 _SBF(4, 0x02) #define SSS_AES_FIFO_MODE _BIT(3) #define SSS_AES_CHAIN_MODE_ECB _SBF(1, 0x00) #define SSS_AES_CHAIN_MODE_CBC _SBF(1, 0x01) #define SSS_AES_CHAIN_MODE_CTR _SBF(1, 0x02) #define SSS_AES_MODE_DECRYPT _BIT(0) #define SSS_REG_AES_STATUS 0x04 #define SSS_AES_BUSY _BIT(2) #define SSS_AES_INPUT_READY _BIT(1) #define SSS_AES_OUTPUT_READY _BIT(0) #define SSS_REG_AES_IN_DATA(s) (0x10 + (s << 2)) #define SSS_REG_AES_OUT_DATA(s) (0x20 + (s << 2)) #define SSS_REG_AES_IV_DATA(s) (0x30 + (s << 2)) #define SSS_REG_AES_CNT_DATA(s) (0x40 + (s << 2)) #define SSS_REG_AES_KEY_DATA(s) (0x80 + (s << 2)) #define SSS_REG(dev, reg) ((dev)->ioaddr + (SSS_REG_##reg)) #define SSS_READ(dev, reg) __raw_readl(SSS_REG(dev, reg)) #define SSS_WRITE(dev, reg, val) __raw_writel((val), SSS_REG(dev, reg)) #define SSS_AES_REG(dev, reg) ((dev)->aes_ioaddr + SSS_REG_##reg) #define SSS_AES_WRITE(dev, reg, val) __raw_writel((val), \ SSS_AES_REG(dev, reg)) /* HW engine modes */ #define FLAGS_AES_DECRYPT _BIT(0) #define FLAGS_AES_MODE_MASK _SBF(1, 0x03) #define FLAGS_AES_CBC _SBF(1, 0x01) #define FLAGS_AES_CTR _SBF(1, 0x02) #define AES_KEY_LEN 16 #define CRYPTO_QUEUE_LEN 1 /** * struct samsung_aes_variant - platform specific SSS driver data * @has_hash_irq: true if SSS module uses hash interrupt, false otherwise * @aes_offset: AES register offset from SSS module's base. * * Specifies platform specific configuration of SSS module. * Note: A structure for driver specific platform data is used for future * expansion of its usage. */ struct samsung_aes_variant { bool has_hash_irq; unsigned int aes_offset; }; struct s5p_aes_reqctx { unsigned long mode; }; struct s5p_aes_ctx { struct s5p_aes_dev *dev; uint8_t aes_key[AES_MAX_KEY_SIZE]; uint8_t nonce[CTR_RFC3686_NONCE_SIZE]; int keylen; }; struct s5p_aes_dev { struct device *dev; struct clk *clk; void __iomem *ioaddr; void __iomem *aes_ioaddr; int irq_hash; int irq_fc; struct ablkcipher_request *req; struct s5p_aes_ctx *ctx; struct scatterlist *sg_src; struct scatterlist *sg_dst; struct tasklet_struct tasklet; struct crypto_queue queue; bool busy; spinlock_t lock; struct samsung_aes_variant *variant; }; static struct s5p_aes_dev *s5p_dev; static const struct samsung_aes_variant s5p_aes_data = { .has_hash_irq = true, .aes_offset = 0x4000, }; static const struct samsung_aes_variant exynos_aes_data = { .has_hash_irq = false, .aes_offset = 0x200, }; static const struct of_device_id s5p_sss_dt_match[] = { { .compatible = "samsung,s5pv210-secss", .data = &s5p_aes_data, }, { .compatible = "samsung,exynos4210-secss", .data = &exynos_aes_data, }, { }, }; MODULE_DEVICE_TABLE(of, s5p_sss_dt_match); static inline struct samsung_aes_variant *find_s5p_sss_version (struct platform_device *pdev) { if (IS_ENABLED(CONFIG_OF) && (pdev->dev.of_node)) { const struct of_device_id *match; match = of_match_node(s5p_sss_dt_match, pdev->dev.of_node); return (struct samsung_aes_variant *)match->data; } return (struct samsung_aes_variant *) platform_get_device_id(pdev)->driver_data; } static void s5p_set_dma_indata(struct s5p_aes_dev *dev, struct scatterlist *sg) { SSS_WRITE(dev, FCBRDMAS, sg_dma_address(sg)); SSS_WRITE(dev, FCBRDMAL, sg_dma_len(sg)); } static void s5p_set_dma_outdata(struct s5p_aes_dev *dev, struct scatterlist *sg) { SSS_WRITE(dev, FCBTDMAS, sg_dma_address(sg)); SSS_WRITE(dev, FCBTDMAL, sg_dma_len(sg)); } static void s5p_aes_complete(struct s5p_aes_dev *dev, int err) { /* holding a lock outside */ dev->req->base.complete(&dev->req->base, err); dev->busy = false; } static void s5p_unset_outdata(struct s5p_aes_dev *dev) { dma_unmap_sg(dev->dev, dev->sg_dst, 1, DMA_FROM_DEVICE); } static void s5p_unset_indata(struct s5p_aes_dev *dev) { dma_unmap_sg(dev->dev, dev->sg_src, 1, DMA_TO_DEVICE); } static int s5p_set_outdata(struct s5p_aes_dev *dev, struct scatterlist *sg) { int err; if (!IS_ALIGNED(sg_dma_len(sg), AES_BLOCK_SIZE)) { err = -EINVAL; goto exit; } if (!sg_dma_len(sg)) { err = -EINVAL; goto exit; } err = dma_map_sg(dev->dev, sg, 1, DMA_FROM_DEVICE); if (!err) { err = -ENOMEM; goto exit; } dev->sg_dst = sg; err = 0; exit: return err; } static int s5p_set_indata(struct s5p_aes_dev *dev, struct scatterlist *sg) { int err; if (!IS_ALIGNED(sg_dma_len(sg), AES_BLOCK_SIZE)) { err = -EINVAL; goto exit; } if (!sg_dma_len(sg)) { err = -EINVAL; goto exit; } err = dma_map_sg(dev->dev, sg, 1, DMA_TO_DEVICE); if (!err) { err = -ENOMEM; goto exit; } dev->sg_src = sg; err = 0; exit: return err; } static void s5p_aes_tx(struct s5p_aes_dev *dev) { int err = 0; s5p_unset_outdata(dev); if (!sg_is_last(dev->sg_dst)) { err = s5p_set_outdata(dev, sg_next(dev->sg_dst)); if (err) { s5p_aes_complete(dev, err); return; } s5p_set_dma_outdata(dev, dev->sg_dst); } else { s5p_aes_complete(dev, err); dev->busy = true; tasklet_schedule(&dev->tasklet); } } static void s5p_aes_rx(struct s5p_aes_dev *dev) { int err; s5p_unset_indata(dev); if (!sg_is_last(dev->sg_src)) { err = s5p_set_indata(dev, sg_next(dev->sg_src)); if (err) { s5p_aes_complete(dev, err); return; } s5p_set_dma_indata(dev, dev->sg_src); } } static irqreturn_t s5p_aes_interrupt(int irq, void *dev_id) { struct platform_device *pdev = dev_id; struct s5p_aes_dev *dev = platform_get_drvdata(pdev); uint32_t status; unsigned long flags; spin_lock_irqsave(&dev->lock, flags); if (irq == dev->irq_fc) { status = SSS_READ(dev, FCINTSTAT); if (status & SSS_FCINTSTAT_BRDMAINT) s5p_aes_rx(dev); if (status & SSS_FCINTSTAT_BTDMAINT) s5p_aes_tx(dev); SSS_WRITE(dev, FCINTPEND, status); } spin_unlock_irqrestore(&dev->lock, flags); return IRQ_HANDLED; } static void s5p_set_aes(struct s5p_aes_dev *dev, uint8_t *key, uint8_t *iv, unsigned int keylen) { void __iomem *keystart; if (iv) memcpy(dev->aes_ioaddr + SSS_REG_AES_IV_DATA(0), iv, 0x10); if (keylen == AES_KEYSIZE_256) keystart = dev->aes_ioaddr + SSS_REG_AES_KEY_DATA(0); else if (keylen == AES_KEYSIZE_192) keystart = dev->aes_ioaddr + SSS_REG_AES_KEY_DATA(2); else keystart = dev->aes_ioaddr + SSS_REG_AES_KEY_DATA(4); memcpy(keystart, key, keylen); } static void s5p_aes_crypt_start(struct s5p_aes_dev *dev, unsigned long mode) { struct ablkcipher_request *req = dev->req; uint32_t aes_control; int err; unsigned long flags; aes_control = SSS_AES_KEY_CHANGE_MODE; if (mode & FLAGS_AES_DECRYPT) aes_control |= SSS_AES_MODE_DECRYPT; if ((mode & FLAGS_AES_MODE_MASK) == FLAGS_AES_CBC) aes_control |= SSS_AES_CHAIN_MODE_CBC; else if ((mode & FLAGS_AES_MODE_MASK) == FLAGS_AES_CTR) aes_control |= SSS_AES_CHAIN_MODE_CTR; if (dev->ctx->keylen == AES_KEYSIZE_192) aes_control |= SSS_AES_KEY_SIZE_192; else if (dev->ctx->keylen == AES_KEYSIZE_256) aes_control |= SSS_AES_KEY_SIZE_256; aes_control |= SSS_AES_FIFO_MODE; /* as a variant it is possible to use byte swapping on DMA side */ aes_control |= SSS_AES_BYTESWAP_DI | SSS_AES_BYTESWAP_DO | SSS_AES_BYTESWAP_IV | SSS_AES_BYTESWAP_KEY | SSS_AES_BYTESWAP_CNT; spin_lock_irqsave(&dev->lock, flags); SSS_WRITE(dev, FCINTENCLR, SSS_FCINTENCLR_BTDMAINTENCLR | SSS_FCINTENCLR_BRDMAINTENCLR); SSS_WRITE(dev, FCFIFOCTRL, 0x00); err = s5p_set_indata(dev, req->src); if (err) goto indata_error; err = s5p_set_outdata(dev, req->dst); if (err) goto outdata_error; SSS_AES_WRITE(dev, AES_CONTROL, aes_control); s5p_set_aes(dev, dev->ctx->aes_key, req->info, dev->ctx->keylen); s5p_set_dma_indata(dev, req->src); s5p_set_dma_outdata(dev, req->dst); SSS_WRITE(dev, FCINTENSET, SSS_FCINTENSET_BTDMAINTENSET | SSS_FCINTENSET_BRDMAINTENSET); spin_unlock_irqrestore(&dev->lock, flags); return; outdata_error: s5p_unset_indata(dev); indata_error: s5p_aes_complete(dev, err); spin_unlock_irqrestore(&dev->lock, flags); } static void s5p_tasklet_cb(unsigned long data) { struct s5p_aes_dev *dev = (struct s5p_aes_dev *)data; struct crypto_async_request *async_req, *backlog; struct s5p_aes_reqctx *reqctx; unsigned long flags; spin_lock_irqsave(&dev->lock, flags); backlog = crypto_get_backlog(&dev->queue); async_req = crypto_dequeue_request(&dev->queue); if (!async_req) { dev->busy = false; spin_unlock_irqrestore(&dev->lock, flags); return; } spin_unlock_irqrestore(&dev->lock, flags); if (backlog) backlog->complete(backlog, -EINPROGRESS); dev->req = ablkcipher_request_cast(async_req); dev->ctx = crypto_tfm_ctx(dev->req->base.tfm); reqctx = ablkcipher_request_ctx(dev->req); s5p_aes_crypt_start(dev, reqctx->mode); } static int s5p_aes_handle_req(struct s5p_aes_dev *dev, struct ablkcipher_request *req) { unsigned long flags; int err; spin_lock_irqsave(&dev->lock, flags); err = ablkcipher_enqueue_request(&dev->queue, req); if (dev->busy) { spin_unlock_irqrestore(&dev->lock, flags); goto exit; } dev->busy = true; spin_unlock_irqrestore(&dev->lock, flags); tasklet_schedule(&dev->tasklet); exit: return err; } static int s5p_aes_crypt(struct ablkcipher_request *req, unsigned long mode) { struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req); struct s5p_aes_ctx *ctx = crypto_ablkcipher_ctx(tfm); struct s5p_aes_reqctx *reqctx = ablkcipher_request_ctx(req); struct s5p_aes_dev *dev = ctx->dev; if (!IS_ALIGNED(req->nbytes, AES_BLOCK_SIZE)) { pr_err("request size is not exact amount of AES blocks\n"); return -EINVAL; } reqctx->mode = mode; return s5p_aes_handle_req(dev, req); } static int s5p_aes_setkey(struct crypto_ablkcipher *cipher, const uint8_t *key, unsigned int keylen) { struct crypto_tfm *tfm = crypto_ablkcipher_tfm(cipher); struct s5p_aes_ctx *ctx = crypto_tfm_ctx(tfm); if (keylen != AES_KEYSIZE_128 && keylen != AES_KEYSIZE_192 && keylen != AES_KEYSIZE_256) return -EINVAL; memcpy(ctx->aes_key, key, keylen); ctx->keylen = keylen; return 0; } static int s5p_aes_ecb_encrypt(struct ablkcipher_request *req) { return s5p_aes_crypt(req, 0); } static int s5p_aes_ecb_decrypt(struct ablkcipher_request *req) { return s5p_aes_crypt(req, FLAGS_AES_DECRYPT); } static int s5p_aes_cbc_encrypt(struct ablkcipher_request *req) { return s5p_aes_crypt(req, FLAGS_AES_CBC); } static int s5p_aes_cbc_decrypt(struct ablkcipher_request *req) { return s5p_aes_crypt(req, FLAGS_AES_DECRYPT | FLAGS_AES_CBC); } static int s5p_aes_cra_init(struct crypto_tfm *tfm) { struct s5p_aes_ctx *ctx = crypto_tfm_ctx(tfm); ctx->dev = s5p_dev; tfm->crt_ablkcipher.reqsize = sizeof(struct s5p_aes_reqctx); return 0; } static struct crypto_alg algs[] = { { .cra_name = "ecb(aes)", .cra_driver_name = "ecb-aes-s5p", .cra_priority = 100, .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC | CRYPTO_ALG_KERN_DRIVER_ONLY, .cra_blocksize = AES_BLOCK_SIZE, .cra_ctxsize = sizeof(struct s5p_aes_ctx), .cra_alignmask = 0x0f, .cra_type = &crypto_ablkcipher_type, .cra_module = THIS_MODULE, .cra_init = s5p_aes_cra_init, .cra_u.ablkcipher = { .min_keysize = AES_MIN_KEY_SIZE, .max_keysize = AES_MAX_KEY_SIZE, .setkey = s5p_aes_setkey, .encrypt = s5p_aes_ecb_encrypt, .decrypt = s5p_aes_ecb_decrypt, } }, { .cra_name = "cbc(aes)", .cra_driver_name = "cbc-aes-s5p", .cra_priority = 100, .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC | CRYPTO_ALG_KERN_DRIVER_ONLY, .cra_blocksize = AES_BLOCK_SIZE, .cra_ctxsize = sizeof(struct s5p_aes_ctx), .cra_alignmask = 0x0f, .cra_type = &crypto_ablkcipher_type, .cra_module = THIS_MODULE, .cra_init = s5p_aes_cra_init, .cra_u.ablkcipher = { .min_keysize = AES_MIN_KEY_SIZE, .max_keysize = AES_MAX_KEY_SIZE, .ivsize = AES_BLOCK_SIZE, .setkey = s5p_aes_setkey, .encrypt = s5p_aes_cbc_encrypt, .decrypt = s5p_aes_cbc_decrypt, } }, }; static int s5p_aes_probe(struct platform_device *pdev) { int i, j, err = -ENODEV; struct s5p_aes_dev *pdata; struct device *dev = &pdev->dev; struct resource *res; struct samsung_aes_variant *variant; if (s5p_dev) return -EEXIST; pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); if (!pdata) return -ENOMEM; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); pdata->ioaddr = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(pdata->ioaddr)) return PTR_ERR(pdata->ioaddr); variant = find_s5p_sss_version(pdev); pdata->clk = devm_clk_get(dev, "secss"); if (IS_ERR(pdata->clk)) { dev_err(dev, "failed to find secss clock source\n"); return -ENOENT; } err = clk_prepare_enable(pdata->clk); if (err < 0) { dev_err(dev, "Enabling SSS clk failed, err %d\n", err); return err; } spin_lock_init(&pdata->lock); pdata->aes_ioaddr = pdata->ioaddr + variant->aes_offset; pdata->irq_fc = platform_get_irq(pdev, 0); if (pdata->irq_fc < 0) { err = pdata->irq_fc; dev_warn(dev, "feed control interrupt is not available.\n"); goto err_irq; } err = devm_request_irq(dev, pdata->irq_fc, s5p_aes_interrupt, IRQF_SHARED, pdev->name, pdev); if (err < 0) { dev_warn(dev, "feed control interrupt is not available.\n"); goto err_irq; } if (variant->has_hash_irq) { pdata->irq_hash = platform_get_irq(pdev, 1); if (pdata->irq_hash < 0) { err = pdata->irq_hash; dev_warn(dev, "hash interrupt is not available.\n"); goto err_irq; } err = devm_request_irq(dev, pdata->irq_hash, s5p_aes_interrupt, IRQF_SHARED, pdev->name, pdev); if (err < 0) { dev_warn(dev, "hash interrupt is not available.\n"); goto err_irq; } } pdata->busy = false; pdata->variant = variant; pdata->dev = dev; platform_set_drvdata(pdev, pdata); s5p_dev = pdata; tasklet_init(&pdata->tasklet, s5p_tasklet_cb, (unsigned long)pdata); crypto_init_queue(&pdata->queue, CRYPTO_QUEUE_LEN); for (i = 0; i < ARRAY_SIZE(algs); i++) { err = crypto_register_alg(&algs[i]); if (err) goto err_algs; } pr_info("s5p-sss driver registered\n"); return 0; err_algs: dev_err(dev, "can't register '%s': %d\n", algs[i].cra_name, err); for (j = 0; j < i; j++) crypto_unregister_alg(&algs[j]); tasklet_kill(&pdata->tasklet); err_irq: clk_disable_unprepare(pdata->clk); s5p_dev = NULL; return err; } static int s5p_aes_remove(struct platform_device *pdev) { struct s5p_aes_dev *pdata = platform_get_drvdata(pdev); int i; if (!pdata) return -ENODEV; for (i = 0; i < ARRAY_SIZE(algs); i++) crypto_unregister_alg(&algs[i]); tasklet_kill(&pdata->tasklet); clk_disable_unprepare(pdata->clk); s5p_dev = NULL; return 0; } static struct platform_driver s5p_aes_crypto = { .probe = s5p_aes_probe, .remove = s5p_aes_remove, .driver = { .name = "s5p-secss", .of_match_table = s5p_sss_dt_match, }, }; module_platform_driver(s5p_aes_crypto); MODULE_DESCRIPTION("S5PV210 AES hw acceleration support."); MODULE_LICENSE("GPL v2"); MODULE_AUTHOR("Vladimir Zapolskiy <vzapolskiy@gmail.com>");