From patchwork Mon Aug 9 13:20:46 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [02/12] mxc_nand: rework get_dev_status Date: Mon, 09 Aug 2010 03:20:46 -0000 From: Sascha Hauer X-Patchwork-Id: 61271 Message-Id: <1281360053-8386-3-git-send-email-s.hauer@pengutronix.de> To: linux-mtd@lists.infradead.org Cc: Baruch Siach , Sascha Hauer , John Ogness , linux-arm-kernel@lists.infradead.org We save/restore the value in the buffer anyway, so it makes no difference whether we use main_area0 or main_area1. So, we can use main_area0 and remove main_area1 from the driver which is otherwise unused. Also, clean up the comments in get_dev_status. Signed-off-by: Sascha Hauer --- drivers/mtd/nand/mxc_nand.c | 21 +++++++++------------ 1 files changed, 9 insertions(+), 12 deletions(-) diff --git a/drivers/mtd/nand/mxc_nand.c b/drivers/mtd/nand/mxc_nand.c index abec73a..6654446 100644 --- a/drivers/mtd/nand/mxc_nand.c +++ b/drivers/mtd/nand/mxc_nand.c @@ -102,7 +102,6 @@ struct mxc_nand_host { void *spare0; void *main_area0; - void *main_area1; void __iomem *base; void __iomem *regs; @@ -305,25 +304,24 @@ static void send_read_id(struct mxc_nand_host *host) * NAND device status and returns the current status. */ static uint16_t get_dev_status(struct mxc_nand_host *host) { - void __iomem *main_buf = host->main_area1; + void __iomem *main_buf = host->main_area0; uint32_t store; uint16_t ret; - /* Issue status request to NAND device */ - /* store the main area1 first word, later do recovery */ + writew(0x0, NFC_V1_V2_BUF_ADDR); + + /* + * The device status is stored in main_area0. To + * prevent corruption of the buffer save the value + * and restore it afterwards. + */ store = readl(main_buf); - /* NANDFC buffer 1 is used for device status to prevent - * corruption of read/write buffer on status requests. */ - writew(1, host->regs + NFC_BUF_ADDR); writew(NFC_STATUS, host->regs + NFC_CONFIG2); - - /* Wait for operation to complete */ wait_op_done(host, true); - /* Status is placed in first word of main buffer */ - /* get status, then recovery area 1 data */ ret = readw(main_buf); + writel(store, main_buf); return ret; @@ -761,7 +759,6 @@ static int __init mxcnd_probe(struct platform_device *pdev) } host->main_area0 = host->base; - host->main_area1 = host->base + 0x200; if (nfc_is_v21()) { host->regs = host->base + 0x1e00;