From c50d35a9fdb628c5fcce5c2d4ab5ad9bedb2edb9 Mon Sep 17 00:00:00 2001 From: Huang Shijie Date: Thu, 13 Sep 2012 14:57:57 +0800 Subject: [PATCH] mtd: gpmi: simplify the DLL setting code The setting DLL code is a little mess. Just simplify the code and the comments. Signed-off-by: Huang Shijie Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse --- drivers/mtd/nand/gpmi-nand/gpmi-lib.c | 22 +++++++++------------- 1 file changed, 9 insertions(+), 13 deletions(-) diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c index 2d1f77c0527e..010665ca631a 100644 --- a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c +++ b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c @@ -779,30 +779,26 @@ void gpmi_begin(struct gpmi_nand_data *this) writel(BM_GPMI_CTRL1_DLL_ENABLE, gpmi_regs + HW_GPMI_CTRL1_CLR); /* Clear out the DLL control fields. */ - writel(BM_GPMI_CTRL1_RDN_DELAY, gpmi_regs + HW_GPMI_CTRL1_CLR); - writel(BM_GPMI_CTRL1_HALF_PERIOD, gpmi_regs + HW_GPMI_CTRL1_CLR); + reg = BM_GPMI_CTRL1_RDN_DELAY | BM_GPMI_CTRL1_HALF_PERIOD; + writel(reg, gpmi_regs + HW_GPMI_CTRL1_CLR); /* If no sample delay is called for, return immediately. */ if (!hw.sample_delay_factor) return; - /* Configure the HALF_PERIOD flag. */ - if (hw.use_half_periods) - writel(BM_GPMI_CTRL1_HALF_PERIOD, - gpmi_regs + HW_GPMI_CTRL1_SET); + /* Set RDN_DELAY or HALF_PERIOD. */ + reg = ((hw.use_half_periods) ? BM_GPMI_CTRL1_HALF_PERIOD : 0) + | BF_GPMI_CTRL1_RDN_DELAY(hw.sample_delay_factor); - /* Set the delay factor. */ - writel(BF_GPMI_CTRL1_RDN_DELAY(hw.sample_delay_factor), - gpmi_regs + HW_GPMI_CTRL1_SET); + writel(reg, gpmi_regs + HW_GPMI_CTRL1_SET); - /* Enable the DLL. */ + /* At last, we enable the DLL. */ writel(BM_GPMI_CTRL1_DLL_ENABLE, gpmi_regs + HW_GPMI_CTRL1_SET); /* * After we enable the GPMI DLL, we have to wait 64 clock cycles before - * we can use the GPMI. - * - * Calculate the amount of time we need to wait, in microseconds. + * we can use the GPMI. Calculate the amount of time we need to wait, + * in microseconds. */ clock_period_in_ns = NSEC_PER_SEC / clk_get_rate(r->clock[0]); dll_wait_time_in_us = (clock_period_in_ns * 64) / 1000;