diff options
| author |   Lucas Stach <l.stach@pengutronix.de> | 2013-06-05 15:13:26 +0200 |
|---|---|---|
| committer |   Chris Ball <cjb@laptop.org> | 2013-06-27 11:29:41 -0400 |
| commit | 0ddf03c95bbb4f4ed57281fa7b781472950df749 (patch) | |
| tree | c7e231559aaace73c1ff488c50b65c8c0370565e /drivers | |
| parent | mmc: sdhci-esdhc: calculate sdclk divider from controller clock (diff) | |
| download | linux-dev-0ddf03c95bbb4f4ed57281fa7b781472950df749.tar.xz linux-dev-0ddf03c95bbb4f4ed57281fa7b781472950df749.zip | |
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')
| -rw-r--r-- | drivers/mmc/host/sdhci-esdhc-imx.c | 18 |
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 |