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

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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: Hein Tibosch <hein_tibosch@yahoo.es>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
This commit is contained in:
Hein_Tibosch 2012-08-30 16:34:38 +00:00 committed by Chris Ball
parent ac940938df
commit ccdfe6122f
1 changed files with 13 additions and 13 deletions
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26
drivers/mmc/host/atmel-mci.c
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@ -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;