On Wed, Jul 28, 2010 at 01:54:21PM +0800, Roy Zang wrote:
> P4080 ESDHC controller induces weird register setting.
> This patch adds the workaround to correct the weird register setting.
>
> Signed-off-by: Roy Zang <tie-fei.z...@freescale.com>
> ---
> drivers/mmc/host/sdhci-of-core.c | 5 +++++
> drivers/mmc/host/sdhci.c | 13 +++++++++++++
> drivers/mmc/host/sdhci.h | 2 ++
> 3 files changed, 20 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-of-core.c
> b/drivers/mmc/host/sdhci-of-core.c
> index 0c30242..1b6945a 100644
> --- a/drivers/mmc/host/sdhci-of-core.c
> +++ b/drivers/mmc/host/sdhci-of-core.c
> @@ -164,6 +164,11 @@ static int __devinit sdhci_of_probe(struct of_device
> *ofdev,
> if (sdhci_of_wp_inverted(np))
> host->quirks |= SDHCI_QUIRK_INVERTED_WRITE_PROTECT;
>
> + if (of_device_is_compatible(np, "fsl,p4080-esdhc")) {
> + host->quirks |= SDHCI_QUIRK_QORIQ_REG_WEIRD;
> + host->quirks &= ~SDHCI_QUIRK_INVERTED_WRITE_PROTECT;
You do not mention this change in the patch description, why?
> + }
> +
> clk = of_get_property(np, "clock-frequency", &size);
> if (clk && size == sizeof(*clk) && *clk)
> of_host->clock = *clk;
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 1424d08..b5b3627 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -788,6 +788,15 @@ static void sdhci_prepare_data(struct sdhci_host *host,
> struct mmc_data *data)
> sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
> }
>
> + /* The default value of DMAS bits of Protocol Control Register is not
> + * correct. clear these two bits to use simple DMA */
> +#define ESDHCI_CTRL_DMAS_MASK 0xFFFFFCFF
> + if (host->quirks & SDHCI_QUIRK_QORIQ_REG_WEIRD) {
> + ctrl = sdhci_readl(host, SDHCI_HOST_CONTROL);
> + ctrl = ctrl & ESDHCI_CTRL_DMAS_MASK;
> + sdhci_writel(host, ctrl, SDHCI_HOST_CONTROL);
> + }
You should implement register quirks via SDHCI IO accessors.
See esdhc_writew() for example.
> if (!(host->flags & SDHCI_REQ_USE_DMA)) {
> int flags;
>
> @@ -1699,6 +1708,10 @@ int sdhci_add_host(struct sdhci_host *host)
>
> caps = sdhci_readl(host, SDHCI_CAPABILITIES);
>
> + /* Workaround for P4080 host controller capabilities */
> + if (host->quirks & SDHCI_QUIRK_QORIQ_REG_WEIRD)
> + caps &= ~(SDHCI_CAN_VDD_180 | SDHCI_CAN_VDD_330);
Ditto. Make a quirk for cap register. Or implement
SDHCI_QUIRK_NO_VDD_180 and SDHCI_QUIRK_NO_VDD_300 quirks
instead.
Thanks,
--
Anton Vorontsov
email: cbouatmai...@gmail.com
irc://irc.freenode.net/bd2
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