Commit ccdfe612 authored by Hein_Tibosch's avatar Hein_Tibosch Committed by Chris Ball
Browse files

mmc: atmel-mci: DMA can be used with other controllers 



After the latest changes to atmel-mci, it could not be used with
DMA on the AVR32 platform. This patch will allow to use DMA again
and it will avoid access to MCI register ATMCI_DMA.

Even if the IP version is lower than v3xx and doesn't have the DMA
configuration register, DMA transfers can be used with a different
controller than the Atmel AHB DMA one. For instance, some AVR chips
use the Synopsys DesignWare AHB DMA controller.

Signed-off-by: default avatarHein Tibosch <hein_tibosch@yahoo.es>
Acked-by: default avatarLudovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: default avatarChris Ball <cjb@laptop.org>
parent ac940938

drivers/mmc/host/atmel-mci.c

+13 −13
Original line number Diff line number Diff line
@@ -74,7 +74,7 @@ enum atmci_pdc_buf { 
};



struct atmel_mci_caps {

	bool    has_dma;

	bool    has_dma_conf_reg;

	bool    has_pdc;

	bool    has_cfg_reg;

	bool    has_cstor_reg;
@@ -421,7 +421,7 @@ static int atmci_regs_show(struct seq_file *s, void *v) 
	atmci_show_status_reg(s, "SR", buf[ATMCI_SR / 4]);

	atmci_show_status_reg(s, "IMR", buf[ATMCI_IMR / 4]);



	if (host->caps.has_dma) {

	if (host->caps.has_dma_conf_reg) {

		u32 val;



		val = buf[ATMCI_DMA / 4];
@@ -841,7 +841,7 @@ static void atmci_dma_complete(void *arg) 


	dev_vdbg(&host->pdev->dev, "DMA complete\n");



	if (host->caps.has_dma)

	if (host->caps.has_dma_conf_reg)

		/* Disable DMA hardware handshaking on MCI */

		atmci_writel(host, ATMCI_DMA, atmci_readl(host, ATMCI_DMA) & ~ATMCI_DMAEN);
@@ -1028,7 +1028,9 @@ atmci_prepare_data_dma(struct atmel_mci *host, struct mmc_data *data) 
		maxburst = atmci_convert_chksize(host->dma_conf.dst_maxburst);

	}



	atmci_writel(host, ATMCI_DMA, ATMCI_DMA_CHKSIZE(maxburst) | ATMCI_DMAEN);

	if (host->caps.has_dma_conf_reg)

		atmci_writel(host, ATMCI_DMA, ATMCI_DMA_CHKSIZE(maxburst) |

			ATMCI_DMAEN);



	sglen = dma_map_sg(chan->device->dev, data->sg,

			data->sg_len, direction);
@@ -2243,7 +2245,10 @@ static bool atmci_configure_dma(struct atmel_mci *host) 


	pdata = host->pdev->dev.platform_data;



	if (pdata && find_slave_dev(pdata->dma_slave)) {

	if (!pdata)

		return false;



	if (pdata->dma_slave && find_slave_dev(pdata->dma_slave)) {

		dma_cap_mask_t mask;



		/* Try to grab a DMA channel */
@@ -2284,7 +2289,7 @@ static void __init atmci_get_cap(struct atmel_mci *host) 
	dev_info(&host->pdev->dev,

			"version: 0x%x\n", version);



	host->caps.has_dma = 0;

	host->caps.has_dma_conf_reg = 0;

	host->caps.has_pdc = 1;

	host->caps.has_cfg_reg = 0;

	host->caps.has_cstor_reg = 0;
@@ -2302,12 +2307,7 @@ static void __init atmci_get_cap(struct atmel_mci *host) 
		host->caps.has_odd_clk_div = 1;

	case 0x400:

	case 0x300:

#ifdef CONFIG_AT_HDMAC

		host->caps.has_dma = 1;

#else

		dev_info(&host->pdev->dev,

			"has dma capability but dma engine is not selected, then use pio\n");

#endif

		host->caps.has_dma_conf_reg = 1;

		host->caps.has_pdc = 0;

		host->caps.has_cfg_reg = 1;

		host->caps.has_cstor_reg = 1;
@@ -2388,7 +2388,7 @@ static int __init atmci_probe(struct platform_device *pdev) 


	/* Get MCI capabilities and set operations according to it */

	atmci_get_cap(host);

	if (host->caps.has_dma && atmci_configure_dma(host)) {

	if (atmci_configure_dma(host)) {

		host->prepare_data = &atmci_prepare_data_dma;

		host->submit_data = &atmci_submit_data_dma;

		host->stop_transfer = &atmci_stop_transfer_dma;

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