Device tree provides option to specify the max freqency with property
"max-frequency" in dts and common parse function mmc_of_parse() will
parse it and use this value to set host->f_max to tell the MMC core
the maxinum frequency the host works.
However, current sdhci driver will finally overwrite this value with
host->max_clk regardless of the max-frequency property.
This patch makes sure not overwrite the max-frequency set from device
tree and do basic sanity check.
Signed-off-by: Dong Aisheng <aisheng.dong@xxxxxxxxxxxxx>
---
drivers/mmc/host/sdhci.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index bc14452..0781c92 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -2866,6 +2866,7 @@ int sdhci_add_host(struct sdhci_host *host)
u32 max_current_caps;
unsigned int ocr_avail;
unsigned int override_timeout_clk;
+ u32 max_clk;
int ret;
WARN_ON(host == NULL);
@@ -3047,18 +3048,22 @@ int sdhci_add_host(struct sdhci_host *host)
* Set host parameters.
*/
mmc->ops = &sdhci_ops;
- mmc->f_max = host->max_clk;
+ max_clk = host->max_clk;
+
if (host->ops->get_min_clock)
mmc->f_min = host->ops->get_min_clock(host);
else if (host->version >= SDHCI_SPEC_300) {
if (host->clk_mul) {
mmc->f_min = (host->max_clk * host->clk_mul) / 1024;
- mmc->f_max = host->max_clk * host->clk_mul;
+ max_clk = host->max_clk * host->clk_mul;
} else
mmc->f_min = host->max_clk / SDHCI_MAX_DIV_SPEC_300;
} else
mmc->f_min = host->max_clk / SDHCI_MAX_DIV_SPEC_200;
+ if (!mmc->f_max || (mmc->f_max && (mmc->f_max > max_clk)))
+ mmc->f_max = max_clk;
+
if (!(host->quirks & SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK)) {
host->timeout_clk = (caps[0] & SDHCI_TIMEOUT_CLK_MASK) >>
SDHCI_TIMEOUT_CLK_SHIFT;
--
1.9.1
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