On 03/15/16 00:54, David Lechner wrote:
> The davinci arch now has dma_slave_map tables for dma resources, so it is
> no longer necessary to pass dma resources through the platform device.
>
> Signed-off-by: David Lechner <david@xxxxxxxxxxxxxx>
> ---
>
> v2 changes: Remove platform_get_resource completly instead of just ignoring it.
>
>
> drivers/mmc/host/davinci_mmc.c | 19 ++-----------------
> 1 file changed, 2 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c
> index 8d10a92..dc96401 100644
> --- a/drivers/mmc/host/davinci_mmc.c
> +++ b/drivers/mmc/host/davinci_mmc.c
> @@ -202,7 +202,6 @@ struct mmc_davinci_host {
> u32 buffer_bytes_left;
> u32 bytes_left;
>
> - u32 rxdma, txdma;
> struct dma_chan *dma_tx;
> struct dma_chan *dma_rx;
> bool use_dma;
> @@ -520,16 +519,14 @@ static int __init davinci_acquire_dma_channels(struct mmc_davinci_host *host)
> 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");
> + dma_request_slave_channel(mmc_dev(host->mmc), "tx");
you would need to use dma_request_chan() to be able to rely on the legacy
channel mapping.
I have staged commits for converting all daVinci and OMAP drivers, I'll attach
the patch I have for davinci-mmc for reference.
When we convert to use the dma_request_chan() we can handle deferred probing
also...
> if (!host->dma_tx) {
> dev_err(mmc_dev(host->mmc), "Can't get dma_tx channel\n");
> return -ENODEV;
> }
>
> host->dma_rx =
> - dma_request_slave_channel_compat(mask, edma_filter_fn,
> - &host->rxdma, mmc_dev(host->mmc), "rx");
> + dma_request_slave_channel(mmc_dev(host->mmc), "rx");
> if (!host->dma_rx) {
> dev_err(mmc_dev(host->mmc), "Can't get dma_rx channel\n");
> r = -ENODEV;
> @@ -1251,18 +1248,6 @@ static int __init davinci_mmcsd_probe(struct platform_device *pdev)
> host = mmc_priv(mmc);
> 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->base = devm_ioremap(&pdev->dev, mem->start, mem_size);
> if (!host->base)
>
--
Péter
>From c349c76720ffa6e203eff3865de2da8e4c0b415c Mon Sep 17 00:00:00 2001
From: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
Date: Mon, 21 Dec 2015 12:47:07 +0200
Subject: [PATCH] mmc: davinci_mmc: Use dma_request_chan() to requesting DMA
channel
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@xxxxxx>
---
drivers/mmc/host/davinci_mmc.c | 52 ++++++++++++------------------------------
1 file changed, 14 insertions(+), 38 deletions(-)
diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c
index 693144e7427b..9edc37d207d2 100644
--- a/drivers/mmc/host/davinci_mmc.c
+++ b/drivers/mmc/host/davinci_mmc.c
@@ -32,12 +32,10 @@
#include <linux/delay.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
-#include <linux/edma.h>
#include <linux/mmc/mmc.h>
#include <linux/of.h>
#include <linux/of_device.h>
-#include <linux/platform_data/edma.h>
#include <linux/platform_data/mmc-davinci.h>
/*
@@ -513,35 +511,20 @@ davinci_release_dma_channels(struct mmc_davinci_host *host)
static int __init davinci_acquire_dma_channels(struct mmc_davinci_host *host)
{
- int r;
- dma_cap_mask_t mask;
-
- 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) {
+ host->dma_tx = dma_request_chan(mmc_dev(host->mmc), "tx");
+ if (IS_ERR(host->dma_tx)) {
dev_err(mmc_dev(host->mmc), "Can't get dma_tx channel\n");
- return -ENODEV;
+ return PTR_ERR(host->dma_tx);
}
- host->dma_rx =
- dma_request_slave_channel_compat(mask, edma_filter_fn,
- &host->rxdma, mmc_dev(host->mmc), "rx");
- if (!host->dma_rx) {
+ host->dma_rx = dma_request_chan(mmc_dev(host->mmc), "rx");
+ if (IS_ERR(host->dma_rx)) {
dev_err(mmc_dev(host->mmc), "Can't get dma_rx channel\n");
- r = -ENODEV;
- goto free_master_write;
+ dma_release_channel(host->dma_tx);
+ return PTR_ERR(host->dma_rx);
}
return 0;
-
-free_master_write:
- dma_release_channel(host->dma_tx);
-
- return r;
}
/*----------------------------------------------------------------------*/
@@ -1253,18 +1236,6 @@ static int __init davinci_mmcsd_probe(struct platform_device *pdev)
host = mmc_priv(mmc);
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->base = ioremap(mem->start, mem_size);
if (!host->base)
@@ -1291,8 +1262,13 @@ static int __init davinci_mmcsd_probe(struct platform_device *pdev)
host->mmc_irq = irq;
host->sdio_irq = platform_get_irq(pdev, 1);
- if (host->use_dma && davinci_acquire_dma_channels(host) != 0)
- host->use_dma = 0;
+ if (host->use_dma) {
+ 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. */
mmc->caps |= MMC_CAP_NEEDS_POLL;
--
2.7.3
