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authorLucas Stach <l.stach@pengutronix.de>2013-06-05 15:13:26 +0200
committerChris Ball <cjb@laptop.org>2013-06-27 11:29:41 -0400
commit0ddf03c95bbb4f4ed57281fa7b781472950df749 (patch)
treec7e231559aaace73c1ff488c50b65c8c0370565e /drivers/mmc
parent8ba9580a8045b6d5fed66e13b77599f3d8a77fed (diff)
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mmc: esdhc-imx: parse max-frequency from devicetree
In order to make it possible to reduce the SD bus frequency, parse the optional "max-frequency" attribute as documented in devicetree/bindings/mmc/mmc.txt Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Acked-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Chris Ball <cjb@laptop.org>
Diffstat (limited to 'drivers/mmc')
-rw-r--r--drivers/mmc/host/sdhci-esdhc-imx.c18
1 files changed, 17 insertions, 1 deletions
diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index eb1310ca021e..1dd5ba858754 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -384,6 +384,20 @@ static void esdhc_writeb_le(struct sdhci_host *host, u8 val, int reg)
}
}
+static unsigned int esdhc_pltfm_get_max_clock(struct sdhci_host *host)
+{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct pltfm_imx_data *imx_data = pltfm_host->priv;
+ struct esdhc_platform_data *boarddata = &imx_data->boarddata;
+
+ u32 f_host = clk_get_rate(pltfm_host->clk);
+
+ if (boarddata->f_max && (boarddata->f_max < f_host))
+ return boarddata->f_max;
+ else
+ return f_host;
+}
+
static unsigned int esdhc_pltfm_get_min_clock(struct sdhci_host *host)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
@@ -447,7 +461,7 @@ static const struct sdhci_ops sdhci_esdhc_ops = {
.write_w = esdhc_writew_le,
.write_b = esdhc_writeb_le,
.set_clock = esdhc_pltfm_set_clock,
- .get_max_clock = sdhci_pltfm_clk_get_max_clock,
+ .get_max_clock = esdhc_pltfm_get_max_clock,
.get_min_clock = esdhc_pltfm_get_min_clock,
.get_ro = esdhc_pltfm_get_ro,
.platform_bus_width = esdhc_pltfm_bus_width,
@@ -490,6 +504,8 @@ sdhci_esdhc_imx_probe_dt(struct platform_device *pdev,
of_property_read_u32(np, "bus-width", &boarddata->max_bus_width);
+ of_property_read_u32(np, "max-frequency", &boarddata->f_max);
+
return 0;
}
#else