mtd: lpc32xx_slc: Make driver independent of AMBA DMA engine driver

This patch makes the SLC NAND driver independent of the single AMBA DMA engine
driver by using the platform data provided dma_filter callback.

Signed-off-by: Roland Stigge <[e-mail]>
Signed-off-by: Artem Bityutskiy <[e-mail]>
Signed-off-by: David Woodhouse <[e-mail]>

drivers/mtd/nand/lpc32xx_slc.c

···
 #include <linux/of.h>
 #include <linux/of_mtd.h>
 #include <linux/of_gpio.h>
-#include <linux/amba/pl08x.h>
+#include <linux/mtd/lpc32xx_slc.h>
 
 #define LPC32XX_MODNAME		"lpc32xx-nand"
 
···
 
 struct lpc32xx_nand_host {
 	struct nand_chip	nand_chip;
+	struct lpc32xx_slc_platform_data *pdata;
 	struct clk		*clk;
 	struct mtd_info		mtd;
 	void __iomem		*io_base;
···
 	struct mtd_info *mtd = &host->mtd;
 	dma_cap_mask_t mask;
 
+	if (!host->pdata || !host->pdata->dma_filter) {
+		dev_err(mtd->dev.parent, "no DMA platform data\n");
+		return -ENOENT;
+	}
+
 	dma_cap_zero(mask);
 	dma_cap_set(DMA_SLAVE, mask);
-	host->dma_chan = dma_request_channel(mask, pl08x_filter_id, "nand-slc");
+	host->dma_chan = dma_request_channel(mask, host->pdata->dma_filter,
+					     "nand-slc");
 	if (!host->dma_chan) {
 		dev_err(mtd->dev.parent, "Failed to request DMA channel\n");
 		return -EBUSY;
···
 		return -EBUSY;
 	}
 	lpc32xx_wp_disable(host);
+
+	host->pdata = pdev->dev.platform_data;
 
 	mtd = &host->mtd;
 	chip = &host->nand_chip;

include/linux/mtd/lpc32xx_slc.h

···
+/*
+ * Platform data for LPC32xx SoC SLC NAND controller
+ *
+ * Copyright © 2012 Roland Stigge
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __LINUX_MTD_LPC32XX_SLC_H
+#define __LINUX_MTD_LPC32XX_SLC_H
+
+#include <linux/dmaengine.h>
+
+struct lpc32xx_slc_platform_data {
+	bool (*dma_filter)(struct dma_chan *chan, void *filter_param);
+};
+
+#endif  /* __LINUX_MTD_LPC32XX_SLC_H */