From: Ulf Hansson <ulf.hansson@xxxxxxxxxx> Add a cache variable in the host struct that reflects the current data in the MMCIDATACTRL register. This patch will not introduce any functional change but instead provide an easy option to keep specific bits in the register between each data transfer. Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> --- drivers/mmc/host/mmci.c | 17 ++++++++++++++--- drivers/mmc/host/mmci.h | 1 + 2 files changed, 15 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c index 8d4ceb8..4530217 100644 --- a/drivers/mmc/host/mmci.c +++ b/drivers/mmc/host/mmci.c @@ -191,6 +191,17 @@ static void mmci_write_pwrreg(struct mmci_host *host, u32 pwr) /* * This must be called with host->lock held */ +static void mmci_write_datactrlreg(struct mmci_host *host, u32 datactrl) +{ + if (host->datactrl_reg != datactrl) { + host->datactrl_reg = datactrl; + writel(datactrl, host->base + MMCIDATACTRL); + } +} + +/* + * This must be called with host->lock held + */ static void mmci_set_clkreg(struct mmci_host *host, unsigned int desired) { struct variant_data *variant = host->variant; @@ -275,7 +286,7 @@ static void mmci_set_mask1(struct mmci_host *host, unsigned int mask) static void mmci_stop_data(struct mmci_host *host) { - writel(0, host->base + MMCIDATACTRL); + mmci_write_datactrlreg(host, 0); mmci_set_mask1(host, 0); host->data = NULL; } @@ -552,7 +563,7 @@ static int mmci_dma_start_data(struct mmci_host *host, unsigned int datactrl) datactrl |= MCI_DPSM_DMAENABLE; /* Trigger the DMA transfer */ - writel(datactrl, host->base + MMCIDATACTRL); + mmci_write_datactrlreg(host, datactrl); /* * Let the MMCI say when the data is ended and it's time @@ -750,7 +761,7 @@ static void mmci_start_data(struct mmci_host *host, struct mmc_data *data) irqmask = MCI_TXFIFOHALFEMPTYMASK; } - writel(datactrl, base + MMCIDATACTRL); + mmci_write_datactrlreg(host, datactrl); writel(readl(base + MMCIMASK0) & ~MCI_DATAENDMASK, base + MMCIMASK0); mmci_set_mask1(host, irqmask); } diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h index 1383c9c..0b6cc54 100644 --- a/drivers/mmc/host/mmci.h +++ b/drivers/mmc/host/mmci.h @@ -183,6 +183,7 @@ struct mmci_host { unsigned int cclk; u32 pwr_reg; u32 clk_reg; + u32 datactrl_reg; bool vqmmc_enabled; struct mmci_platform_data *plat; struct variant_data *variant; -- 1.7.10 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html