From 93af53b8633c4cb474585158512182b21219d743 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ezequiel=20Garc=C3=ADa?= Date: Sat, 20 Sep 2014 17:53:12 +0100 Subject: [PATCH] nand: omap2: Remove horrible ifdefs to fix module probe The current code abuses ifdefs to determine if the selected ECC scheme is supported by the running kernel. As a result the code is hard to read, and it also fails to load as a module. This commit removes all the ifdefs and instead introduces a function omap2_nand_ecc_check() to check if the ECC is supported by using IS_ENABLED(CONFIG_xxx). Since IS_ENABLED() is true when a config is =y or =m, this change fixes the module so it can be loaded with no issues. Acked-by: Roger Quadros Signed-off-by: Ezequiel Garcia Signed-off-by: Brian Norris --- drivers/mtd/nand/omap2.c | 130 +++++++++++++++++++++----------------- include/linux/platform_data/elm.h | 16 +++++ 2 files changed, 87 insertions(+), 59 deletions(-) diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c index e1a9b310c159..f97a4ffd489d 100644 --- a/drivers/mtd/nand/omap2.c +++ b/drivers/mtd/nand/omap2.c @@ -136,7 +136,6 @@ #define BADBLOCK_MARKER_LENGTH 2 -#ifdef CONFIG_MTD_NAND_OMAP_BCH static u_char bch16_vector[] = {0xf5, 0x24, 0x1c, 0xd0, 0x61, 0xb3, 0xf1, 0x55, 0x2e, 0x2c, 0x86, 0xa3, 0xed, 0x36, 0x1b, 0x78, 0x48, 0x76, 0xa9, 0x3b, 0x97, 0xd1, 0x7a, 0x93, @@ -144,7 +143,6 @@ static u_char bch16_vector[] = {0xf5, 0x24, 0x1c, 0xd0, 0x61, 0xb3, 0xf1, 0x55, static u_char bch8_vector[] = {0xf3, 0xdb, 0x14, 0x16, 0x8b, 0xd2, 0xbe, 0xcc, 0xac, 0x6b, 0xff, 0x99, 0x7b}; static u_char bch4_vector[] = {0x00, 0x6b, 0x31, 0xdd, 0x41, 0xbc, 0x10}; -#endif /* oob info generated runtime depending on ecc algorithm and layout selected */ static struct nand_ecclayout omap_oobinfo; @@ -1292,7 +1290,6 @@ static int __maybe_unused omap_calculate_ecc_bch(struct mtd_info *mtd, return 0; } -#ifdef CONFIG_MTD_NAND_OMAP_BCH /** * erased_sector_bitflips - count bit flips * @data: data sector buffer @@ -1593,33 +1590,71 @@ static int omap_read_page_bch(struct mtd_info *mtd, struct nand_chip *chip, /** * is_elm_present - checks for presence of ELM module by scanning DT nodes * @omap_nand_info: NAND device structure containing platform data - * @bch_type: 0x0=BCH4, 0x1=BCH8, 0x2=BCH16 */ -static int is_elm_present(struct omap_nand_info *info, - struct device_node *elm_node, enum bch_ecc bch_type) +static bool is_elm_present(struct omap_nand_info *info, + struct device_node *elm_node) { struct platform_device *pdev; - struct nand_ecc_ctrl *ecc = &info->nand.ecc; - int err; + /* check whether elm-id is passed via DT */ if (!elm_node) { pr_err("nand: error: ELM DT node not found\n"); - return -ENODEV; + return false; } pdev = of_find_device_by_node(elm_node); /* check whether ELM device is registered */ if (!pdev) { pr_err("nand: error: ELM device not found\n"); - return -ENODEV; + return false; } /* ELM module available, now configure it */ info->elm_dev = &pdev->dev; - err = elm_config(info->elm_dev, bch_type, - (info->mtd.writesize / ecc->size), ecc->size, ecc->bytes); + return true; +} - return err; +static bool omap2_nand_ecc_check(struct omap_nand_info *info, + struct omap_nand_platform_data *pdata) +{ + bool ecc_needs_bch, ecc_needs_omap_bch, ecc_needs_elm; + + switch (info->ecc_opt) { + case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW: + case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: + ecc_needs_omap_bch = false; + ecc_needs_bch = true; + ecc_needs_elm = false; + break; + case OMAP_ECC_BCH4_CODE_HW: + case OMAP_ECC_BCH8_CODE_HW: + case OMAP_ECC_BCH16_CODE_HW: + ecc_needs_omap_bch = true; + ecc_needs_bch = false; + ecc_needs_elm = true; + break; + default: + ecc_needs_omap_bch = false; + ecc_needs_bch = false; + ecc_needs_elm = false; + break; + } + + if (ecc_needs_bch && !IS_ENABLED(CONFIG_MTD_NAND_ECC_BCH)) { + dev_err(&info->pdev->dev, + "CONFIG_MTD_NAND_ECC_BCH not enabled\n"); + return false; + } + if (ecc_needs_omap_bch && !IS_ENABLED(CONFIG_MTD_NAND_OMAP_BCH)) { + dev_err(&info->pdev->dev, + "CONFIG_MTD_NAND_OMAP_BCH not enabled\n"); + return false; + } + if (ecc_needs_elm && !is_elm_present(info, pdata->elm_of_node)) { + dev_err(&info->pdev->dev, "ELM not available\n"); + return false; + } + + return true; } -#endif /* CONFIG_MTD_NAND_ECC_BCH */ static int omap_nand_probe(struct platform_device *pdev) { @@ -1797,6 +1832,11 @@ static int omap_nand_probe(struct platform_device *pdev) goto return_error; } + if (!omap2_nand_ecc_check(info, pdata)) { + err = -EINVAL; + goto return_error; + } + /* populate MTD interface based on ECC scheme */ ecclayout = &omap_oobinfo; switch (info->ecc_opt) { @@ -1829,7 +1869,6 @@ static int omap_nand_probe(struct platform_device *pdev) break; case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW: -#ifdef CONFIG_MTD_NAND_ECC_BCH pr_info("nand: using OMAP_ECC_BCH4_CODE_HW_DETECTION_SW\n"); nand_chip->ecc.mode = NAND_ECC_HW; nand_chip->ecc.size = 512; @@ -1861,14 +1900,8 @@ static int omap_nand_probe(struct platform_device *pdev) err = -EINVAL; } break; -#else - pr_err("nand: error: CONFIG_MTD_NAND_ECC_BCH not enabled\n"); - err = -EINVAL; - goto return_error; -#endif case OMAP_ECC_BCH4_CODE_HW: -#ifdef CONFIG_MTD_NAND_OMAP_BCH pr_info("nand: using OMAP_ECC_BCH4_CODE_HW ECC scheme\n"); nand_chip->ecc.mode = NAND_ECC_HW; nand_chip->ecc.size = 512; @@ -1890,21 +1923,15 @@ static int omap_nand_probe(struct platform_device *pdev) /* reserved marker already included in ecclayout->eccbytes */ ecclayout->oobfree->offset = ecclayout->eccpos[ecclayout->eccbytes - 1] + 1; - /* This ECC scheme requires ELM H/W block */ - if (is_elm_present(info, pdata->elm_of_node, BCH4_ECC) < 0) { - pr_err("nand: error: could not initialize ELM\n"); - err = -ENODEV; + + err = elm_config(info->elm_dev, BCH4_ECC, + info->mtd.writesize / nand_chip->ecc.size, + nand_chip->ecc.size, nand_chip->ecc.bytes); + if (err < 0) goto return_error; - } break; -#else - pr_err("nand: error: CONFIG_MTD_NAND_OMAP_BCH not enabled\n"); - err = -EINVAL; - goto return_error; -#endif case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: -#ifdef CONFIG_MTD_NAND_ECC_BCH pr_info("nand: using OMAP_ECC_BCH8_CODE_HW_DETECTION_SW\n"); nand_chip->ecc.mode = NAND_ECC_HW; nand_chip->ecc.size = 512; @@ -1937,14 +1964,8 @@ static int omap_nand_probe(struct platform_device *pdev) goto return_error; } break; -#else - pr_err("nand: error: CONFIG_MTD_NAND_ECC_BCH not enabled\n"); - err = -EINVAL; - goto return_error; -#endif case OMAP_ECC_BCH8_CODE_HW: -#ifdef CONFIG_MTD_NAND_OMAP_BCH pr_info("nand: using OMAP_ECC_BCH8_CODE_HW ECC scheme\n"); nand_chip->ecc.mode = NAND_ECC_HW; nand_chip->ecc.size = 512; @@ -1956,12 +1977,13 @@ static int omap_nand_probe(struct platform_device *pdev) nand_chip->ecc.calculate = omap_calculate_ecc_bch; nand_chip->ecc.read_page = omap_read_page_bch; nand_chip->ecc.write_page = omap_write_page_bch; - /* This ECC scheme requires ELM H/W block */ - err = is_elm_present(info, pdata->elm_of_node, BCH8_ECC); - if (err < 0) { - pr_err("nand: error: could not initialize ELM\n"); + + err = elm_config(info->elm_dev, BCH8_ECC, + info->mtd.writesize / nand_chip->ecc.size, + nand_chip->ecc.size, nand_chip->ecc.bytes); + if (err < 0) goto return_error; - } + /* define ECC layout */ ecclayout->eccbytes = nand_chip->ecc.bytes * (mtd->writesize / @@ -1973,14 +1995,8 @@ static int omap_nand_probe(struct platform_device *pdev) ecclayout->oobfree->offset = ecclayout->eccpos[ecclayout->eccbytes - 1] + 1; break; -#else - pr_err("nand: error: CONFIG_MTD_NAND_OMAP_BCH not enabled\n"); - err = -EINVAL; - goto return_error; -#endif case OMAP_ECC_BCH16_CODE_HW: -#ifdef CONFIG_MTD_NAND_OMAP_BCH pr_info("using OMAP_ECC_BCH16_CODE_HW ECC scheme\n"); nand_chip->ecc.mode = NAND_ECC_HW; nand_chip->ecc.size = 512; @@ -1991,12 +2007,13 @@ static int omap_nand_probe(struct platform_device *pdev) nand_chip->ecc.calculate = omap_calculate_ecc_bch; nand_chip->ecc.read_page = omap_read_page_bch; nand_chip->ecc.write_page = omap_write_page_bch; - /* This ECC scheme requires ELM H/W block */ - err = is_elm_present(info, pdata->elm_of_node, BCH16_ECC); - if (err < 0) { - pr_err("ELM is required for this ECC scheme\n"); + + err = elm_config(info->elm_dev, BCH16_ECC, + info->mtd.writesize / nand_chip->ecc.size, + nand_chip->ecc.size, nand_chip->ecc.bytes); + if (err < 0) goto return_error; - } + /* define ECC layout */ ecclayout->eccbytes = nand_chip->ecc.bytes * (mtd->writesize / @@ -2008,11 +2025,6 @@ static int omap_nand_probe(struct platform_device *pdev) ecclayout->oobfree->offset = ecclayout->eccpos[ecclayout->eccbytes - 1] + 1; break; -#else - pr_err("nand: error: CONFIG_MTD_NAND_OMAP_BCH not enabled\n"); - err = -EINVAL; - goto return_error; -#endif default: pr_err("nand: error: invalid or unsupported ECC scheme\n"); err = -EINVAL; diff --git a/include/linux/platform_data/elm.h b/include/linux/platform_data/elm.h index 780d1e97f620..b8686c00f15f 100644 --- a/include/linux/platform_data/elm.h +++ b/include/linux/platform_data/elm.h @@ -42,8 +42,24 @@ struct elm_errorvec { int error_loc[16]; }; +#if IS_ENABLED(CONFIG_MTD_NAND_OMAP_BCH) void elm_decode_bch_error_page(struct device *dev, u8 *ecc_calc, struct elm_errorvec *err_vec); int elm_config(struct device *dev, enum bch_ecc bch_type, int ecc_steps, int ecc_step_size, int ecc_syndrome_size); +#else +static inline void +elm_decode_bch_error_page(struct device *dev, u8 *ecc_calc, + struct elm_errorvec *err_vec) +{ +} + +static inline int elm_config(struct device *dev, enum bch_ecc bch_type, + int ecc_steps, int ecc_step_size, + int ecc_syndrome_size) +{ + return -ENOSYS; +} +#endif /* CONFIG_MTD_NAND_ECC_BCH */ + #endif /* __ELM_H */ -- 2.11.0