From mboxrd@z Thu Jan 1 00:00:00 1970 From: jbe@pengutronix.de (Juergen Beisert) Date: Tue, 8 Dec 2009 10:56:40 +0100 Subject: [PATCH] [NAND] S3C2410: Fix NFC clock enable/disable imbalance Message-ID: <200912081056.40210.jbe@pengutronix.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org When unmounting an mtd filesystem the s3c2410_nand_select_chip() function gets called again with "chip == -1". In this case the current code disables the NFC clock at least a second time, so it does not work anymore. Clock disabling should only happen if it was really enabled. Signed-off-by: Juergen Beisert --- drivers/mtd/nand/s3c2410.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) Index: linux-2.6.32/drivers/mtd/nand/s3c2410.c =================================================================== --- linux-2.6.32.orig/drivers/mtd/nand/s3c2410.c +++ linux-2.6.32/drivers/mtd/nand/s3c2410.c @@ -329,12 +329,16 @@ static void s3c2410_nand_select_chip(str struct s3c2410_nand_mtd *nmtd; struct nand_chip *this = mtd->priv; unsigned long cur; + int clock_enabled; nmtd = this->priv; info = nmtd->info; - if (chip != -1 && allow_clk_stop(info)) + if (chip != -1 && allow_clk_stop(info)) { clk_enable(info->clk); + clock_enabled = 1; + } else + clock_enabled = 0; cur = readl(info->sel_reg); @@ -356,7 +360,7 @@ static void s3c2410_nand_select_chip(str writel(cur, info->sel_reg); - if (chip == -1 && allow_clk_stop(info)) + if (chip == -1 && allow_clk_stop(info) && clock_enabled != 0) clk_disable(info->clk); } -- Pengutronix e.K. | Juergen Beisert | Linux Solutions for Science and Industry | Phone: +49-8766-939 228 | Vertretung Sued/Muenchen, Germany | Fax: +49-5121-206917-5555 | Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de/ |