From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 11 Sep 2013 16:02:07 -0700 From: Brian Norris To: Josh Wu Subject: Re: [PATCH 1/2] mtd: atmel_nand: remove unneeded ifdef CONFIG_OF Message-ID: <20130911230207.GE4550@ld-irv-0074.broadcom.com> References: <1378200028-15415-1-git-send-email-josh.wu@atmel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1378200028-15415-1-git-send-email-josh.wu@atmel.com> Cc: nicolas.ferre@atmel.com, plagnioj@jcrosoft.com, linux-mtd@lists.infradead.org, linux-arm-kernel@lists.infradead.org, dedekind1@gmail.com List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi Josh, On Tue, Sep 03, 2013 at 05:20:27PM +0800, Josh Wu wrote: > Since following commit > f3b391425d21e6138e57b2432d91134e0bc2b975 This commit ID will likely change before it gets merged, since there may be rebasing, and David usually adds his signoff. David or I can take care of that later though. > (of_mtd: Add no-op stubs to support CONFIG_OF=n) > > implements the stub for CONFIG_OF=n. Now we can safely remove all > CONFIG_OF in atmel_nand. (Thanks to Ezequiel Garcia's for this protype) I'm not quite so sure about this patch, as I was about the pxa3xx patch. With pxa3xx, the compiler can easily tell that pxa3xx_nand_probe_dt() will return 0 without doing anything in the !CONFIG_OF case (and so will likely remove the dead code), so it's no benefit to have the #ifdef. But in this driver, the atmel_of_init_port() function can't be trivially determined to do nothing (and in fact, it does something in either CONFIG_OF=y or =n case). It's only protected by the 'if (pdev->dev.of_node)' check, which the compiler can't predict. So, I don't know if we should remove the #ifdef at the expense of likely significantly larger code. I won't protest, but I won't merge it yet either. Perhaps others have better ideas, or perhaps you can find a good way to work around this -- e.g., check the of_* helpers for -ENOSYS early in atmel_of_init_port()? > Signed-off-by: Josh Wu > --- > drivers/mtd/nand/atmel_nand.c | 14 +------------- > 1 file changed, 1 insertion(+), 13 deletions(-) > > diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c > index 060feea..1ca0724 100644 > --- a/drivers/mtd/nand/atmel_nand.c > +++ b/drivers/mtd/nand/atmel_nand.c > @@ -1449,7 +1449,6 @@ static void atmel_nand_hwctl(struct mtd_info *mtd, int mode) > ecc_writel(host->ecc, CR, ATMEL_ECC_RST); > } > > -#if defined(CONFIG_OF) > static int atmel_of_init_port(struct atmel_nand_host *host, > struct device_node *np) > { > @@ -1457,7 +1456,7 @@ static int atmel_of_init_port(struct atmel_nand_host *host, > u32 offset[2]; > int ecc_mode; > struct atmel_nand_data *board = &host->board; > - enum of_gpio_flags flags; > + enum of_gpio_flags flags = 0; > > if (of_property_read_u32(np, "atmel,nand-addr-offset", &val) == 0) { > if (val >= 32) { > @@ -1540,13 +1539,6 @@ static int atmel_of_init_port(struct atmel_nand_host *host, > > return 0; > } > -#else > -static int atmel_of_init_port(struct atmel_nand_host *host, > - struct device_node *np) > -{ > - return -EINVAL; > -} > -#endif > > static int __init atmel_hw_nand_init_params(struct platform_device *pdev, > struct atmel_nand_host *host) > @@ -2207,14 +2199,12 @@ static int __exit atmel_nand_remove(struct platform_device *pdev) > return 0; > } > > -#if defined(CONFIG_OF) > static const struct of_device_id atmel_nand_dt_ids[] = { > { .compatible = "atmel,at91rm9200-nand" }, > { /* sentinel */ } > }; > > MODULE_DEVICE_TABLE(of, atmel_nand_dt_ids); > -#endif > > static int atmel_nand_nfc_probe(struct platform_device *pdev) > { > @@ -2253,12 +2243,10 @@ static int atmel_nand_nfc_probe(struct platform_device *pdev) > return 0; > } > > -#if defined(CONFIG_OF) > static struct of_device_id atmel_nand_nfc_match[] = { > { .compatible = "atmel,sama5d3-nfc" }, > { /* sentinel */ } > }; > -#endif > > static struct platform_driver atmel_nand_nfc_driver = { > .driver = { Brian