From patchwork Mon Jul 23 01:20:37 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marek Vasut X-Patchwork-Id: 172532 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from merlin.infradead.org (unknown [IPv6:2001:4978:20e::2]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 23BB12C0269 for ; Mon, 23 Jul 2012 11:24:53 +1000 (EST) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1St7MK-0005HM-9g; Mon, 23 Jul 2012 01:22:52 +0000 Received: from casper.infradead.org ([2001:770:15f::2]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1St7Ll-0005Gb-Kc for linux-mtd@merlin.infradead.org; Mon, 23 Jul 2012 01:22:18 +0000 Received: from mail-out.m-online.net ([212.18.0.9]) by casper.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1St7Lg-0000Z4-7V for linux-mtd@lists.infradead.org; Mon, 23 Jul 2012 01:22:15 +0000 Received: from frontend1.mail.m-online.net (unknown [192.168.8.180]) by mail-out.m-online.net (Postfix) with ESMTP id 3WgPyx2RGnz4KK6R; Mon, 23 Jul 2012 03:20:41 +0200 (CEST) X-Auth-Info: CvhPb5IWtp2QBcJ5rNfpokVscTqyrQPv6ozg6Xywvvk= Received: from mashiro.lan (unknown [195.140.253.167]) by smtp-auth.mnet-online.de (Postfix) with ESMTPA id 3WgPyx0lmtzbc2b; Mon, 23 Jul 2012 03:20:40 +0200 (CEST) From: Marek Vasut To: linux-mtd@lists.infradead.org Subject: [PATCH V2] mtd: m25p80: Make fast read configurable via DT Date: Mon, 23 Jul 2012 03:20:37 +0200 Message-Id: <1343006437-11669-1-git-send-email-marex@denx.de> X-Mailer: git-send-email 1.7.10.4 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20120723_022212_400693_B722562A X-CRM114-Status: GOOD ( 21.93 ) X-Spam-Score: -1.9 (-) X-Spam-Report: SpamAssassin version 3.3.2 on casper.infradead.org summary: Content analysis details: (-1.9 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [212.18.0.9 listed in list.dnswl.org] -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: Marek Vasut , Artem Bityutskiy , David Woodhouse , Rob Herring , dedekind1@gmail.com X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: linux-mtd-bounces@lists.infradead.org Errors-To: linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org Add DT property "m25p,fast-read" that signalises the particular chip supports "fast read" opcode. NOTE: I'm not sure where to document this property, as m25p80 is a simple DT device. Any hints please? Signed-off-by: Marek Vasut Cc: Artem Bityutskiy Cc: David Woodhouse --- Documentation/devicetree/bindings/mtd/m25p80.txt | 27 ++++++++++++++++++ drivers/mtd/devices/m25p80.c | 32 +++++++++++++--------- 2 files changed, 46 insertions(+), 13 deletions(-) create mode 100644 Documentation/devicetree/bindings/mtd/m25p80.txt V2: Add documentation for the DT property. (Thanks Rob Herring for helping!) Supersedes [PATCH 3/3] [RFC] mtd: m25p80: Make fast read configurable via DT diff --git a/Documentation/devicetree/bindings/mtd/m25p80.txt b/Documentation/devicetree/bindings/mtd/m25p80.txt new file mode 100644 index 0000000..e05d9b8 --- /dev/null +++ b/Documentation/devicetree/bindings/mtd/m25p80.txt @@ -0,0 +1,27 @@ +* MTD SPI driver for ST M25Pxx (and similar) serial flash chips + +Required properties: +- #address-cells, #size-cells : Must be present if the device has sub-nodes + representing partitions. +- compatible : Should be the name of the chip, see the "m25p_ids" table in + drivers/mtd/devices/m25p80.c +- reg : Chip-Select number +- spi-max-frequency : Maximum frequency of the SPI bus the chip can operate at + +Optional properties: +- m25p,fast-read : Use the "fast read" opcode to read data from the chip instead + of the usual "read" opcode. This opcode isn not supported by + all chips and support for it can not be detected at runtime. + Refer to your chips' datasheet to check if this is supported + by your chip. + +Example: + + flash: s25sl064p@0 { + #address-cells = <1>; + #size-cells = <1>; + compatible = "s25sl064p"; + reg = <0>; + spi-max-frequency = <40000000>; + m25p,fast-read; + }; diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c index d16f75c..c5284cd 100644 --- a/drivers/mtd/devices/m25p80.c +++ b/drivers/mtd/devices/m25p80.c @@ -73,14 +73,6 @@ #define MAX_READY_WAIT_JIFFIES (40 * HZ) /* M25P16 specs 40s max chip erase */ #define MAX_CMD_SIZE 5 -#ifdef CONFIG_M25PXX_USE_FAST_READ -#define OPCODE_READ OPCODE_FAST_READ -#define FAST_READ_DUMMY_BYTE 1 -#else -#define OPCODE_READ OPCODE_NORM_READ -#define FAST_READ_DUMMY_BYTE 0 -#endif - #define JEDEC_MFR(_jedec_id) ((_jedec_id) >> 16) /****************************************************************************/ @@ -93,6 +85,7 @@ struct m25p { u16 addr_width; u8 erase_opcode; u8 *command; + bool fast_read; }; static inline struct m25p *mtd_to_m25p(struct mtd_info *mtd) @@ -342,6 +335,7 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len, struct m25p *flash = mtd_to_m25p(mtd); struct spi_transfer t[2]; struct spi_message m; + uint8_t opcode; pr_debug("%s: %s from 0x%08x, len %zd\n", dev_name(&flash->spi->dev), __func__, (u32)from, len); @@ -354,7 +348,7 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len, * Should add 1 byte DUMMY_BYTE. */ t[0].tx_buf = flash->command; - t[0].len = m25p_cmdsz(flash) + FAST_READ_DUMMY_BYTE; + t[0].len = m25p_cmdsz(flash) + (flash->fast_read ? 1 : 0); spi_message_add_tail(&t[0], &m); t[1].rx_buf = buf; @@ -376,12 +370,14 @@ static int m25p80_read(struct mtd_info *mtd, loff_t from, size_t len, */ /* Set up the write data buffer. */ - flash->command[0] = OPCODE_READ; + opcode = flash->fast_read ? OPCODE_FAST_READ : OPCODE_NORM_READ; + flash->command[0] = opcode; m25p_addr2cmd(flash, from, flash->command); spi_sync(flash->spi, &m); - *retlen = m.actual_length - m25p_cmdsz(flash) - FAST_READ_DUMMY_BYTE; + *retlen = m.actual_length - m25p_cmdsz(flash) - + (flash->fast_read ? 1 : 0); mutex_unlock(&flash->lock); @@ -804,9 +800,10 @@ static int __devinit m25p_probe(struct spi_device *spi) struct flash_info *info; unsigned i; struct mtd_part_parser_data ppdata; + struct device_node *np = spi->dev.of_node; #ifdef CONFIG_MTD_OF_PARTS - if (!of_device_is_available(spi->dev.of_node)) + if (!of_device_is_available(np)) return -ENODEV; #endif @@ -858,7 +855,8 @@ static int __devinit m25p_probe(struct spi_device *spi) flash = kzalloc(sizeof *flash, GFP_KERNEL); if (!flash) return -ENOMEM; - flash->command = kmalloc(MAX_CMD_SIZE + FAST_READ_DUMMY_BYTE, GFP_KERNEL); + flash->command = kmalloc(MAX_CMD_SIZE + (flash->fast_read ? 1 : 0), + GFP_KERNEL); if (!flash->command) { kfree(flash); return -ENOMEM; @@ -915,6 +913,14 @@ static int __devinit m25p_probe(struct spi_device *spi) flash->page_size = info->page_size; flash->mtd.writebufsize = flash->page_size; + flash->fast_read = false; + if (np && of_find_property(np, "m25p,fast-read", NULL)) + flash->fast_read = true; + +#ifdef CONFIG_M25PXX_USE_FAST_READ + flash->fast_read = true; +#endif + if (info->addr_width) flash->addr_width = info->addr_width; else {