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author | Grant Likely <grant.likely@secretlab.ca> | 2012-05-08 19:35:37 +0200 |
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committer | Grant Likely <grant.likely@secretlab.ca> | 2012-05-08 19:35:37 +0200 |
commit | 7b96c686223a5c902d6a59c7d178f3904f0ab757 (patch) | |
tree | fe328ed56ad3719de3cfebad72ef74e34f1ed92b /drivers/mmc/host/atmel-mci.c | |
parent | gpio: Move DT support code into drivers/gpio (diff) | |
parent | Linux 3.4-rc6 (diff) | |
download | linux-7b96c686223a5c902d6a59c7d178f3904f0ab757.tar.xz linux-7b96c686223a5c902d6a59c7d178f3904f0ab757.zip |
Merge tag 'v3.4-rc6' into gpio/next
Linux 3.4-rc6
Diffstat (limited to 'drivers/mmc/host/atmel-mci.c')
-rw-r--r-- | drivers/mmc/host/atmel-mci.c | 55 |
1 files changed, 37 insertions, 18 deletions
diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c index 9819dc09ce08..e94476beca18 100644 --- a/drivers/mmc/host/atmel-mci.c +++ b/drivers/mmc/host/atmel-mci.c @@ -77,6 +77,7 @@ struct atmel_mci_caps { bool has_cstor_reg; bool has_highspeed; bool has_rwproof; + bool has_odd_clk_div; }; struct atmel_mci_dma { @@ -482,7 +483,14 @@ err: static inline unsigned int atmci_ns_to_clocks(struct atmel_mci *host, unsigned int ns) { - return (ns * (host->bus_hz / 1000000) + 999) / 1000; + /* + * It is easier here to use us instead of ns for the timeout, + * it prevents from overflows during calculation. + */ + unsigned int us = DIV_ROUND_UP(ns, 1000); + + /* Maximum clock frequency is host->bus_hz/2 */ + return us * (DIV_ROUND_UP(host->bus_hz, 2000000)); } static void atmci_set_timeout(struct atmel_mci *host, @@ -1127,16 +1135,27 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) } /* Calculate clock divider */ - clkdiv = DIV_ROUND_UP(host->bus_hz, 2 * clock_min) - 1; - if (clkdiv > 255) { - dev_warn(&mmc->class_dev, - "clock %u too slow; using %lu\n", - clock_min, host->bus_hz / (2 * 256)); - clkdiv = 255; + if (host->caps.has_odd_clk_div) { + clkdiv = DIV_ROUND_UP(host->bus_hz, clock_min) - 2; + if (clkdiv > 511) { + dev_warn(&mmc->class_dev, + "clock %u too slow; using %lu\n", + clock_min, host->bus_hz / (511 + 2)); + clkdiv = 511; + } + host->mode_reg = ATMCI_MR_CLKDIV(clkdiv >> 1) + | ATMCI_MR_CLKODD(clkdiv & 1); + } else { + clkdiv = DIV_ROUND_UP(host->bus_hz, 2 * clock_min) - 1; + if (clkdiv > 255) { + dev_warn(&mmc->class_dev, + "clock %u too slow; using %lu\n", + clock_min, host->bus_hz / (2 * 256)); + clkdiv = 255; + } + host->mode_reg = ATMCI_MR_CLKDIV(clkdiv); } - host->mode_reg = ATMCI_MR_CLKDIV(clkdiv); - /* * WRPROOF and RDPROOF prevent overruns/underruns by * stopping the clock when the FIFO is full/empty. @@ -2007,35 +2026,35 @@ static void __init atmci_get_cap(struct atmel_mci *host) "version: 0x%x\n", version); host->caps.has_dma = 0; - host->caps.has_pdc = 0; + host->caps.has_pdc = 1; host->caps.has_cfg_reg = 0; host->caps.has_cstor_reg = 0; host->caps.has_highspeed = 0; host->caps.has_rwproof = 0; + host->caps.has_odd_clk_div = 0; /* keep only major version number */ switch (version & 0xf00) { - case 0x100: - case 0x200: - host->caps.has_pdc = 1; - host->caps.has_rwproof = 1; - break; - case 0x300: - case 0x400: case 0x500: + host->caps.has_odd_clk_div = 1; + case 0x400: + case 0x300: #ifdef CONFIG_AT_HDMAC host->caps.has_dma = 1; #else - host->caps.has_dma = 0; dev_info(&host->pdev->dev, "has dma capability but dma engine is not selected, then use pio\n"); #endif + host->caps.has_pdc = 0; host->caps.has_cfg_reg = 1; host->caps.has_cstor_reg = 1; host->caps.has_highspeed = 1; + case 0x200: host->caps.has_rwproof = 1; + case 0x100: break; default: + host->caps.has_pdc = 0; dev_warn(&host->pdev->dev, "Unmanaged mci version, set minimum capabilities\n"); break; |