diff options
Diffstat (limited to 'drivers/mmc/host/sdhci-s3c.c')
-rw-r--r-- | drivers/mmc/host/sdhci-s3c.c | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-s3c.c b/drivers/mmc/host/sdhci-s3c.c index aacb862ecc8..5309ab95aad 100644 --- a/drivers/mmc/host/sdhci-s3c.c +++ b/drivers/mmc/host/sdhci-s3c.c @@ -130,6 +130,15 @@ static unsigned int sdhci_s3c_consider_clock(struct sdhci_s3c *ourhost, if (!clksrc) return UINT_MAX; + /* + * Clock divider's step is different as 1 from that of host controller + * when 'clk_type' is S3C_SDHCI_CLK_DIV_EXTERNAL. + */ + if (ourhost->pdata->clk_type) { + rate = clk_round_rate(clksrc, wanted); + return wanted - rate; + } + rate = clk_get_rate(clksrc); for (div = 1; div < 256; div *= 2) { @@ -232,10 +241,79 @@ static unsigned int sdhci_s3c_get_min_clock(struct sdhci_host *host) return min; } +/* sdhci_cmu_get_max_clk - callback to get maximum clock frequency.*/ +static unsigned int sdhci_cmu_get_max_clock(struct sdhci_host *host) +{ + struct sdhci_s3c *ourhost = to_s3c(host); + + return clk_round_rate(ourhost->clk_bus[ourhost->cur_clk], UINT_MAX); +} + +/* sdhci_cmu_get_min_clock - callback to get minimal supported clock value. */ +static unsigned int sdhci_cmu_get_min_clock(struct sdhci_host *host) +{ + struct sdhci_s3c *ourhost = to_s3c(host); + + /* + * initial clock can be in the frequency range of + * 100KHz-400KHz, so we set it as max value. + */ + return clk_round_rate(ourhost->clk_bus[ourhost->cur_clk], 400000); +} + +/* sdhci_cmu_set_clock - callback on clock change.*/ +static void sdhci_cmu_set_clock(struct sdhci_host *host, unsigned int clock) +{ + struct sdhci_s3c *ourhost = to_s3c(host); + + /* don't bother if the clock is going off */ + if (clock == 0) + return; + + sdhci_s3c_set_clock(host, clock); + + clk_set_rate(ourhost->clk_bus[ourhost->cur_clk], clock); + + host->clock = clock; +} + +/** + * sdhci_s3c_platform_8bit_width - support 8bit buswidth + * @host: The SDHCI host being queried + * @width: MMC_BUS_WIDTH_ macro for the bus width being requested + * + * We have 8-bit width support but is not a v3 controller. + * So we add platform_8bit_width() and support 8bit width. + */ +static int sdhci_s3c_platform_8bit_width(struct sdhci_host *host, int width) +{ + u8 ctrl; + + ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL); + + switch (width) { + case MMC_BUS_WIDTH_8: + ctrl |= SDHCI_CTRL_8BITBUS; + ctrl &= ~SDHCI_CTRL_4BITBUS; + break; + case MMC_BUS_WIDTH_4: + ctrl |= SDHCI_CTRL_4BITBUS; + ctrl &= ~SDHCI_CTRL_8BITBUS; + break; + default: + break; + } + + sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL); + + return 0; +} + static struct sdhci_ops sdhci_s3c_ops = { .get_max_clock = sdhci_s3c_get_max_clk, .set_clock = sdhci_s3c_set_clock, .get_min_clock = sdhci_s3c_get_min_clock, + .platform_8bit_width = sdhci_s3c_platform_8bit_width, }; static void sdhci_s3c_notify_change(struct platform_device *dev, int state) @@ -361,6 +439,13 @@ static int __devinit sdhci_s3c_probe(struct platform_device *pdev) clks++; sc->clk_bus[ptr] = clk; + + /* + * save current clock index to know which clock bus + * is used later in overriding functions. + */ + sc->cur_clk = ptr; + clk_enable(clk); dev_info(dev, "clock source %d: %s (%ld Hz)\n", @@ -421,12 +506,29 @@ static int __devinit sdhci_s3c_probe(struct platform_device *pdev) if (pdata->cd_type == S3C_SDHCI_CD_PERMANENT) host->mmc->caps = MMC_CAP_NONREMOVABLE; + if (pdata->host_caps) + host->mmc->caps |= pdata->host_caps; + host->quirks |= (SDHCI_QUIRK_32BIT_DMA_ADDR | SDHCI_QUIRK_32BIT_DMA_SIZE); /* HSMMC on Samsung SoCs uses SDCLK as timeout clock */ host->quirks |= SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK; + /* + * If controller does not have internal clock divider, + * we can use overriding functions instead of default. + */ + if (pdata->clk_type) { + sdhci_s3c_ops.set_clock = sdhci_cmu_set_clock; + sdhci_s3c_ops.get_min_clock = sdhci_cmu_get_min_clock; + sdhci_s3c_ops.get_max_clock = sdhci_cmu_get_max_clock; + } + + /* It supports additional host capabilities if needed */ + if (pdata->host_caps) + host->mmc->caps |= pdata->host_caps; + ret = sdhci_add_host(host); if (ret) { dev_err(dev, "sdhci_add_host() failed\n"); |