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.
v2:
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.
v2: in atmci_configure_dma: check both pdata and pdata->dma_slave
Signed-off-by: Hein Tibosch <hein_tibosch@xxxxxxxx>
Acked-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxx>
---
drivers/mmc/host/atmel-mci.c | 26 +++++++++++++-------------
1 files changed, 13 insertions(+), 13 deletions(-)
diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index f2c115e..a6a5593 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -71,7 +71,7 @@ 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;
@@ -411,7 +411,7 @@ 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];
@@ -767,7 +767,7 @@ 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);
@@ -954,7 +954,9 @@ 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);
@@ -2161,7 +2163,10 @@ 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 */
@@ -2202,7 +2207,7 @@ 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;
@@ -2219,12 +2224,7 @@ 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;
@@ -2298,7 +2298,7 @@ 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;
--
1.7.8.0
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