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path: root/drivers/mmc/host/sdhci-s3c.c
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-rw-r--r--drivers/mmc/host/sdhci-s3c.c102
1 files changed, 102 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-s3c.c b/drivers/mmc/host/sdhci-s3c.c
index aacb862ecc8a..5309ab95aada 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");