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mtd: nand: pxa3xx: Make dma code dependent on dma capable platforms

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This patch adds a macro ARCH_HAS_DMA to compile-out arch specific
dma code, namely pxa_request_dma() and pxa_free_dma(). These symbols
are available only in pxa, which makes impossible to build the driver in
other platforms than ARCH_PXA.

In order to handle non-dma capable platforms, we implement a fallbacks that
allocate buffers as if 'use_dma=false', putting the dma related code
under the ARCH_HAS_DMA conditional.

Please note that the correct way to handle this is to migrate the
dma code to use of the mmp_pdma dmaengine driver. However, currently
this is not possible because the two dmaengine drivers can't work together.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This commit is contained in:
Ezequiel Garcia 2013-08-12 14:14:56 -03:00 committed by David Woodhouse
parent 48cf7efa6b
commit f4db2e3a33
1 changed files with 34 additions and 0 deletions
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34
drivers/mtd/nand/pxa3xx_nand.c
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@ -25,7 +25,14 @@
#include <linux/of.h>
#include <linux/of_device.h>
#if defined(CONFIG_ARCH_PXA) || defined(CONFIG_ARCH_MMP)
#define ARCH_HAS_DMA
#endif
#ifdef ARCH_HAS_DMA
#include <mach/dma.h>
#endif
#include <linux/platform_data/mtd-nand-pxa3xx.h>
#define CHIP_DELAY_TIMEOUT (2 * HZ/10)
@ -381,6 +388,7 @@ static void handle_data_pio(struct pxa3xx_nand_info *info)
}
}
#ifdef ARCH_HAS_DMA
static void start_data_dma(struct pxa3xx_nand_info *info)
{
struct pxa_dma_desc *desc = info->data_desc;
@ -427,6 +435,10 @@ static void pxa3xx_nand_data_dma_irq(int channel, void *data)
enable_int(info, NDCR_INT_MASK);
nand_writel(info, NDSR, NDSR_WRDREQ | NDSR_RDDREQ);
}
#else
static void start_data_dma(struct pxa3xx_nand_info *info)
{}
#endif
static irqreturn_t pxa3xx_nand_irq(int irq, void *devid)
{
@ -905,6 +917,7 @@ static int pxa3xx_nand_detect_config(struct pxa3xx_nand_info *info)
*/
#define MAX_BUFF_SIZE PAGE_SIZE
#ifdef ARCH_HAS_DMA
static int pxa3xx_nand_init_buff(struct pxa3xx_nand_info *info)
{
struct platform_device *pdev = info->pdev;
@ -950,6 +963,20 @@ static void pxa3xx_nand_free_buff(struct pxa3xx_nand_info *info)
kfree(info->data_buff);
}
}
#else
static int pxa3xx_nand_init_buff(struct pxa3xx_nand_info *info)
{
info->data_buff = kmalloc(MAX_BUFF_SIZE, GFP_KERNEL);
if (info->data_buff == NULL)
return -ENOMEM;
return 0;
}
static void pxa3xx_nand_free_buff(struct pxa3xx_nand_info *info)
{
kfree(info->data_buff);
}
#endif
static int pxa3xx_nand_sensing(struct pxa3xx_nand_info *info)
{
@ -1265,6 +1292,13 @@ static int pxa3xx_nand_probe(struct platform_device *pdev)
struct pxa3xx_nand_info *info;
int ret, cs, probe_success;
#ifndef ARCH_HAS_DMA
if (use_dma) {
use_dma = 0;
dev_warn(&pdev->dev,
"This platform can't do DMA on this device\n");
}
#endif
ret = pxa3xx_nand_probe_dt(pdev);
if (ret)
return ret;