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mmc: davinci_mmc: Use dma_request_chan() to requesting DMA channel

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With the new dma_request_chan() the client driver does not need to look for
the DMA resource and it does not need to pass filter_fn anymore.
By switching to the new API the driver can now support deferred probing
against DMA.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit is contained in:
Peter Ujfalusi 2016-03-16 22:45:31 -05:00 committed by Ulf Hansson
parent 33a31ceaf0
commit 0a4d7236c5
1 changed files with 14 additions and 39 deletions
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53
drivers/mmc/host/davinci_mmc.c
View file

@ -32,12 +32,10 @@
#include <linux/delay.h> #include <linux/delay.h>
#include <linux/dmaengine.h> #include <linux/dmaengine.h>
#include <linux/dma-mapping.h> #include <linux/dma-mapping.h>
#include <linux/edma.h>
#include <linux/mmc/mmc.h> #include <linux/mmc/mmc.h>
#include <linux/of.h> #include <linux/of.h>
#include <linux/of_device.h> #include <linux/of_device.h>
#include <linux/platform_data/edma.h>
#include <linux/platform_data/mmc-davinci.h> #include <linux/platform_data/mmc-davinci.h>
/* /*
@ -202,7 +200,6 @@ struct mmc_davinci_host {
u32 buffer_bytes_left; u32 buffer_bytes_left;
u32 bytes_left; u32 bytes_left;
u32 rxdma, txdma;
struct dma_chan *dma_tx; struct dma_chan *dma_tx;
struct dma_chan *dma_rx; struct dma_chan *dma_rx;
bool use_dma; bool use_dma;
@ -513,35 +510,20 @@ davinci_release_dma_channels(struct mmc_davinci_host *host)
static int __init davinci_acquire_dma_channels(struct mmc_davinci_host *host) static int __init davinci_acquire_dma_channels(struct mmc_davinci_host *host)
{ {
int r; host->dma_tx = dma_request_chan(mmc_dev(host->mmc), "tx");
dma_cap_mask_t mask; if (IS_ERR(host->dma_tx)) {
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
host->dma_tx =
dma_request_slave_channel_compat(mask, edma_filter_fn,
&host->txdma, mmc_dev(host->mmc), "tx");
if (!host->dma_tx) {
dev_err(mmc_dev(host->mmc), "Can't get dma_tx channel\n"); dev_err(mmc_dev(host->mmc), "Can't get dma_tx channel\n");
return -ENODEV; return PTR_ERR(host->dma_tx);
} }
host->dma_rx = host->dma_rx = dma_request_chan(mmc_dev(host->mmc), "rx");
dma_request_slave_channel_compat(mask, edma_filter_fn, if (IS_ERR(host->dma_rx)) {
&host->rxdma, mmc_dev(host->mmc), "rx");
if (!host->dma_rx) {
dev_err(mmc_dev(host->mmc), "Can't get dma_rx channel\n"); dev_err(mmc_dev(host->mmc), "Can't get dma_rx channel\n");
r = -ENODEV; dma_release_channel(host->dma_tx);
goto free_master_write; return PTR_ERR(host->dma_rx);
} }
return 0; return 0;
free_master_write:
dma_release_channel(host->dma_tx);
return r;
} }
/*----------------------------------------------------------------------*/ /*----------------------------------------------------------------------*/
@ -1253,18 +1235,6 @@ static int __init davinci_mmcsd_probe(struct platform_device *pdev)
host = mmc_priv(mmc); host = mmc_priv(mmc);
host->mmc = mmc; /* Important */ host->mmc = mmc; /* Important */
r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
if (!r)
dev_warn(&pdev->dev, "RX DMA resource not specified\n");
else
host->rxdma = r->start;
r = platform_get_resource(pdev, IORESOURCE_DMA, 1);
if (!r)
dev_warn(&pdev->dev, "TX DMA resource not specified\n");
else
host->txdma = r->start;
host->mem_res = mem; host->mem_res = mem;
host->base = ioremap(mem->start, mem_size); host->base = ioremap(mem->start, mem_size);
if (!host->base) if (!host->base)
@ -1291,8 +1261,13 @@ static int __init davinci_mmcsd_probe(struct platform_device *pdev)
host->mmc_irq = irq; host->mmc_irq = irq;
host->sdio_irq = platform_get_irq(pdev, 1); host->sdio_irq = platform_get_irq(pdev, 1);
if (host->use_dma && davinci_acquire_dma_channels(host) != 0) if (host->use_dma) {
host->use_dma = 0; ret = davinci_acquire_dma_channels(host);
if (ret == -EPROBE_DEFER)
goto out;
else if (ret)
host->use_dma = 0;
}
/* REVISIT: someday, support IRQ-driven card detection. */ /* REVISIT: someday, support IRQ-driven card detection. */
mmc->caps |= MMC_CAP_NEEDS_POLL; mmc->caps |= MMC_CAP_NEEDS_POLL;