From 3f410690f511f9531fdc0865a931522b049d7b29 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Uwe=20Kleine-K=C3=B6nig?= Date: Tue, 10 Feb 2015 19:59:57 +0100 Subject: [PATCH] mtd: mxc-nand: Do the word to byte mangling in the read_byte callback MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit When the hardware operates in 16 bit mode it always reads 16 bits even for operations that only have the lower 8 bits defined. So the upper bits must be discarded. Do this in the read_byte callback instead of when reading the NAND id to support reading byte wise more than 5 bytes and at other occations (like reading the ONFI parameter page). Signed-off-by: Uwe Kleine-König Signed-off-by: Brian Norris --- drivers/mtd/nand/mxc_nand.c | 34 ++++++++++------------------------ 1 file changed, 10 insertions(+), 24 deletions(-) diff --git a/drivers/mtd/nand/mxc_nand.c b/drivers/mtd/nand/mxc_nand.c index d9637ae34719..aa98a0dddcfb 100644 --- a/drivers/mtd/nand/mxc_nand.c +++ b/drivers/mtd/nand/mxc_nand.c @@ -552,30 +552,17 @@ static void send_page_v1(struct mtd_info *mtd, unsigned int ops) static void send_read_id_v3(struct mxc_nand_host *host) { - struct nand_chip *this = &host->nand; - /* Read ID into main buffer */ writel(NFC_ID, NFC_V3_LAUNCH); wait_op_done(host, true); memcpy32_fromio(host->data_buf, host->main_area0, 16); - - if (this->options & NAND_BUSWIDTH_16) { - /* compress the ID info */ - host->data_buf[1] = host->data_buf[2]; - host->data_buf[2] = host->data_buf[4]; - host->data_buf[3] = host->data_buf[6]; - host->data_buf[4] = host->data_buf[8]; - host->data_buf[5] = host->data_buf[10]; - } } /* Request the NANDFC to perform a read of the NAND device ID. */ static void send_read_id_v1_v2(struct mxc_nand_host *host) { - struct nand_chip *this = &host->nand; - /* NANDFC buffer 0 is used for device ID output */ writew(host->active_cs << 4, NFC_V1_V2_BUF_ADDR); @@ -585,15 +572,6 @@ static void send_read_id_v1_v2(struct mxc_nand_host *host) wait_op_done(host, true); memcpy32_fromio(host->data_buf, host->main_area0, 16); - - if (this->options & NAND_BUSWIDTH_16) { - /* compress the ID info */ - host->data_buf[1] = host->data_buf[2]; - host->data_buf[2] = host->data_buf[4]; - host->data_buf[3] = host->data_buf[6]; - host->data_buf[4] = host->data_buf[8]; - host->data_buf[5] = host->data_buf[10]; - } } static uint16_t get_dev_status_v3(struct mxc_nand_host *host) @@ -719,9 +697,17 @@ static u_char mxc_nand_read_byte(struct mtd_info *mtd) if (host->status_request) return host->devtype_data->get_dev_status(host) & 0xFF; - ret = *(uint8_t *)(host->data_buf + host->buf_start); - host->buf_start++; + if (nand_chip->options & NAND_BUSWIDTH_16) { + /* only take the lower byte of each word */ + ret = *(uint16_t *)(host->data_buf + host->buf_start); + + host->buf_start += 2; + } else { + ret = *(uint8_t *)(host->data_buf + host->buf_start); + host->buf_start++; + } + pr_debug("%s: ret=0x%hhx (start=%u)\n", __func__, ret, host->buf_start); return ret; } -- 2.20.1