From 06f216c83c25adadc231469d51ab133afdfe110a Mon Sep 17 00:00:00 2001 From: Huang Shijie Date: Wed, 18 Dec 2013 23:40:59 +0800 Subject: [PATCH] mtd: gpmi: allocate a proper buffer for non ECC read/write The @data_buffer_dma buffer is used for non ECC read/write. Currently, the length of the buffer is PAGE_SIZE, but the NAND chip may has 8K page or 16K page. So we have to extend it for the large page NAND chips. The gpmi_alloc_dma_buffer will be called twice. The first time is to allocate a temporary buffer for scanning the NAND chip; The second time is to allocate a buffer to store the real page content. This patch allocates a buffer of PAGE_SIZE size for scanning the NAND chip when gpmi_alloc_dma_buffer is called the first time, and allocates a buffer of the real NAND page size for the second time gpmi_alloc_dma_buffer is called. Signed-off-by: Huang Shijie Signed-off-by: Brian Norris --- drivers/mtd/nand/gpmi-nand/gpmi-nand.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c index e2f5820..d1d13d8 100644 --- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c +++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c @@ -783,14 +783,23 @@ static int gpmi_alloc_dma_buffer(struct gpmi_nand_data *this) { struct bch_geometry *geo = &this->bch_geometry; struct device *dev = this->dev; + struct mtd_info *mtd = &this->mtd; /* [1] Allocate a command buffer. PAGE_SIZE is enough. */ this->cmd_buffer = kzalloc(PAGE_SIZE, GFP_DMA | GFP_KERNEL); if (this->cmd_buffer == NULL) goto error_alloc; - /* [2] Allocate a read/write data buffer. PAGE_SIZE is enough. */ - this->data_buffer_dma = kzalloc(PAGE_SIZE, GFP_DMA | GFP_KERNEL); + /* + * [2] Allocate a read/write data buffer. + * The gpmi_alloc_dma_buffer can be called twice. + * We allocate a PAGE_SIZE length buffer if gpmi_alloc_dma_buffer + * is called before the nand_scan_ident; and we allocate a buffer + * of the real NAND page size when the gpmi_alloc_dma_buffer is + * called after the nand_scan_ident. + */ + this->data_buffer_dma = kzalloc(mtd->writesize ?: PAGE_SIZE, + GFP_DMA | GFP_KERNEL); if (this->data_buffer_dma == NULL) goto error_alloc; -- 2.7.4