Commit 27cbd7e8 authored by Arnd Bergmann's avatar Arnd Bergmann Committed by Ulf Hansson
Browse files

mmc: sh_mmcif: rework dma channel handling 



When compiling the sh_mmcif driver for ARM64, we currently
get a harmless build warning:

../drivers/mmc/host/sh_mmcif.c: In function 'sh_mmcif_request_dma_one':
../drivers/mmc/host/sh_mmcif.c:417:4: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
    (void *)pdata->slave_id_tx :
    ^
../drivers/mmc/host/sh_mmcif.c:418:4: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
    (void *)pdata->slave_id_rx;

This could be worked around by adding another cast to uintptr_t, but
I decided to simplify the code a little more to avoid that. This
splits out the platform data using code into a separate function
and builds that only for CONFIG_SUPERH. This part still has a typecast
but does not need a second one. The SH platform code could be further
modified to pass a pointer directly as we do on other architectures
when we have a filter function.

The normal case is simplified further and now just calls
dma_request_slave_channel() directly without going through the
compat handling.

Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent 2e4456f0

drivers/mmc/host/sh_mmcif.c

+38 −46
Original line number Diff line number Diff line
@@ -397,38 +397,26 @@ static void sh_mmcif_start_dma_tx(struct sh_mmcif_host *host) 
}



static struct dma_chan *

sh_mmcif_request_dma_one(struct sh_mmcif_host *host,

			 struct sh_mmcif_plat_data *pdata,

			 enum dma_transfer_direction direction)

sh_mmcif_request_dma_pdata(struct sh_mmcif_host *host, uintptr_t slave_id)

{

	struct dma_slave_config cfg = { 0, };

	struct dma_chan *chan;

	void *slave_data = NULL;

	struct resource *res;

	struct device *dev = sh_mmcif_host_to_dev(host);

	dma_cap_mask_t mask;

	int ret;



	dma_cap_zero(mask);

	dma_cap_set(DMA_SLAVE, mask);

	if (slave_id <= 0)

		return NULL;



	if (pdata)

		slave_data = direction == DMA_MEM_TO_DEV ?

			(void *)pdata->slave_id_tx :

			(void *)pdata->slave_id_rx;



	chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,

				slave_data, dev,

				direction == DMA_MEM_TO_DEV ? "tx" : "rx");



	dev_dbg(dev, "%s: %s: got channel %p\n", __func__,

		direction == DMA_MEM_TO_DEV ? "TX" : "RX", chan);

	return dma_request_channel(mask, shdma_chan_filter, (void *)slave_id);

}



	if (!chan)

		return NULL;

static int sh_mmcif_dma_slave_config(struct sh_mmcif_host *host,

				     struct dma_chan *chan,

				     enum dma_transfer_direction direction)

{

	struct resource *res;

	struct dma_slave_config cfg = { 0, };



	res = platform_get_resource(host->pd, IORESOURCE_MEM, 0);



	cfg.direction = direction;



	if (direction == DMA_DEV_TO_MEM) {
@@ -439,38 +427,42 @@ sh_mmcif_request_dma_one(struct sh_mmcif_host *host, 
		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;

	}



	ret = dmaengine_slave_config(chan, &cfg);

	if (ret < 0) {

		dma_release_channel(chan);

		return NULL;

	}



	return chan;

	return dmaengine_slave_config(chan, &cfg);

}



static void sh_mmcif_request_dma(struct sh_mmcif_host *host,

				 struct sh_mmcif_plat_data *pdata)

static void sh_mmcif_request_dma(struct sh_mmcif_host *host)

{

	struct device *dev = sh_mmcif_host_to_dev(host);

	host->dma_active = false;



	if (pdata) {

		if (pdata->slave_id_tx <= 0 || pdata->slave_id_rx <= 0)

			return;

	} else if (!dev->of_node) {

		return;

	/* We can only either use DMA for both Tx and Rx or not use it at all */

	if (IS_ENABLED(CONFIG_SUPERH) && dev->platform_data) {

		struct sh_mmcif_plat_data *pdata = dev->platform_data;



		host->chan_tx = sh_mmcif_request_dma_pdata(host,

							pdata->slave_id_tx);

		host->chan_rx = sh_mmcif_request_dma_pdata(host,

							pdata->slave_id_rx);

	} else {

		host->chan_tx = dma_request_slave_channel(dev, "tx");

		host->chan_tx = dma_request_slave_channel(dev, "rx");

	}

	dev_dbg(dev, "%s: got channel TX %p RX %p\n", __func__, host->chan_tx,

		host->chan_rx);



	if (!host->chan_tx || !host->chan_rx ||

	    sh_mmcif_dma_slave_config(host, host->chan_tx, DMA_MEM_TO_DEV) ||

	    sh_mmcif_dma_slave_config(host, host->chan_rx, DMA_DEV_TO_MEM))

		goto error;



	/* We can only either use DMA for both Tx and Rx or not use it at all */

	host->chan_tx = sh_mmcif_request_dma_one(host, pdata, DMA_MEM_TO_DEV);

	if (!host->chan_tx)

	return;



	host->chan_rx = sh_mmcif_request_dma_one(host, pdata, DMA_DEV_TO_MEM);

	if (!host->chan_rx) {

error:

	if (host->chan_tx)

		dma_release_channel(host->chan_tx);

		host->chan_tx = NULL;

	}

	if (host->chan_rx)

		dma_release_channel(host->chan_rx);

	host->chan_tx = host->chan_rx = NULL;

}



static void sh_mmcif_release_dma(struct sh_mmcif_host *host)
@@ -1102,7 +1094,7 @@ static void sh_mmcif_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) 
	if (ios->power_mode == MMC_POWER_UP) {

		if (!host->card_present) {

			/* See if we also get DMA */

			sh_mmcif_request_dma(host, dev->platform_data);

			sh_mmcif_request_dma(host);

			host->card_present = true;

		}

		sh_mmcif_set_power(host, ios);

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