On Tue, Mar 30, 2010 at 10:22:03AM +0200, Christian Pellegrin wrote: > Option CONFIG_MTD_NAND_S3C2410_CLKSTOP was broken by higher MTD layers > calling select_chip with -1 twice in a row. This patch fixes the problem > by making sure that clk_disable is not called too many times. > > Signed-off-by: Christian Pellegrin <[email protected]> > --- > drivers/mtd/nand/s3c2410.c | 10 ++++++++-- > 1 files changed, 8 insertions(+), 2 deletions(-) > > diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c > index fa6e9c7..9adecc6 100644 > --- a/drivers/mtd/nand/s3c2410.c > +++ b/drivers/mtd/nand/s3c2410.c > @@ -37,6 +37,7 @@ > #include <linux/slab.h> > #include <linux/clk.h> > #include <linux/cpufreq.h> > +#include <linux/bitops.h> > > #include <linux/mtd/mtd.h> > #include <linux/mtd/nand.h> > @@ -135,6 +136,9 @@ struct s3c2410_nand_info { > #ifdef CONFIG_CPU_FREQ > struct notifier_block freq_transition; > #endif > +#ifdef CONFIG_MTD_NAND_S3C2410_CLKSTOP > + unsigned long clk_running; > +#endif > }; > > /* conversion functions */ > @@ -333,7 +337,8 @@ static void s3c2410_nand_select_chip(struct mtd_info > *mtd, int chip) > nmtd = this->priv; > info = nmtd->info; > > - if (chip != -1 && allow_clk_stop(info)) > + if (chip != -1 && allow_clk_stop(info) && > + !test_and_set_bit(0, &info->clk_running)) > clk_enable(info->clk);
please let me know why you feel the need to use test_and_set_bit on a variable that is single use. > cur = readl(info->sel_reg); > @@ -356,7 +361,8 @@ static void s3c2410_nand_select_chip(struct mtd_info > *mtd, int chip) > > writel(cur, info->sel_reg); > > - if (chip == -1 && allow_clk_stop(info)) > + if (chip == -1 && allow_clk_stop(info) && > + test_and_clear_bit(0, &info->clk_running)) > clk_disable(info->clk); > } > > -- > 1.5.6.5 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" > in > the body of a message to [email protected] > More majordomo info at http://vger.kernel.org/majordomo-info.html -- -- Ben Q: What's a light-year? A: One-third less calories than a regular year. -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
