From da46a0bd42c81a473618e94871500fb792c98727 Mon Sep 17 00:00:00 2001 From: Ian Molton Date: Fri, 12 Jun 2009 21:53:05 +0100 Subject: [PATCH] tmio_mmc: fix clock setup This patch fixes the clock setup in tmio_mmc. * Incorrect divider setting * Cruft written to the clock registers (seemingly harmless but Not Good (tm)) It also eliminates some unnecessary ifs and tidies the loop syntax. Thanks to Philipp Zabel who discovered the divider issue, commenting "Except for the SDCLK = HCLK (divider bypassed) case, the clock setting resulted in double the requested frequency. The smallest possible frequency (f_max/512) is configured with a divider setting 0x80, not 0x40." Signed-off-by: Ian Molton Signed-off-by: Pierre Ossman --- drivers/mmc/host/tmio_mmc.c | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c index fe6d2b6c0161..10951b7131d6 100644 --- a/drivers/mmc/host/tmio_mmc.c +++ b/drivers/mmc/host/tmio_mmc.c @@ -37,22 +37,17 @@ static void tmio_mmc_set_clock(struct tmio_mmc_host *host, int new_clock) { - u32 clk = 0, clock, f_min = host->mmc->f_min; + u32 clk = 0, clock; if (new_clock) { - for (clock = f_min, clk = 0x100; new_clock >= (clock<<1); ) { + for (clock = host->mmc->f_min, clk = 0x80000080; + new_clock >= (clock<<1); clk >>= 1) clock <<= 1; - clk >>= 1; - } - if (clk & 0x1) - clk = 0x20000; - - clk >>= 2; - sd_config_write8(host, CNF_SD_CLK_MODE, (clk & 0x8000) ? 0 : 1); clk |= 0x100; } - sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, clk); + sd_config_write8(host, CNF_SD_CLK_MODE, clk >> 22); + sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, clk & 0x1ff); } static void tmio_mmc_clk_stop(struct tmio_mmc_host *host) -- GitLab