Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753537AbaAWKcF (ORCPT ); Thu, 23 Jan 2014 05:32:05 -0500 Received: from mail-wg0-f53.google.com ([74.125.82.53]:48637 "EHLO mail-wg0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753169AbaAWKcB (ORCPT ); Thu, 23 Jan 2014 05:32:01 -0500 From: Lee Jones To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: linus.walleij@linaro.org, dwmw2@infradead.org, linux-mtd@lists.infradead.org, computersforpeace@gmail.com, Angus.Clark@st.com, DCG_UPD_stlinux_kernel@list.st.com, olivier.clergeaud@st.com, Lee Jones Subject: [PATCH RESEND v4 07/37] mtd: st_spi_fsm: Add support for JEDEC ID extraction Date: Thu, 23 Jan 2014 10:30:55 +0000 Message-Id: <1390473085-24626-8-git-send-email-lee.jones@linaro.org> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1390473085-24626-1-git-send-email-lee.jones@linaro.org> References: <1390473085-24626-1-git-send-email-lee.jones@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Once we start supporting devices it will be handy go detect them dynamically. This will be done using the chip's unique JEDEC ID. This patch allows us to extract a device's JEDEC ID using the a predefined FSM register write sequence. Signed-off-by: Lee Jones --- drivers/mtd/devices/st_spi_fsm.c | 55 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) diff --git a/drivers/mtd/devices/st_spi_fsm.c b/drivers/mtd/devices/st_spi_fsm.c index bb0f20a..8a10f16 100644 --- a/drivers/mtd/devices/st_spi_fsm.c +++ b/drivers/mtd/devices/st_spi_fsm.c @@ -255,6 +255,22 @@ struct stfsm_seq { uint32_t seq_cfg; } __packed __aligned(4); +static struct stfsm_seq stfsm_seq_read_jedec = { + .data_size = TRANSFER_SIZE(8), + .seq_opc[0] = (SEQ_OPC_PADS_1 | + SEQ_OPC_CYCLES(8) | + SEQ_OPC_OPCODE(FLASH_CMD_RDID)), + .seq = { + STFSM_INST_CMD1, + STFSM_INST_DATA_READ, + STFSM_INST_STOP, + }, + .seq_cfg = (SEQ_CFG_PADS_1 | + SEQ_CFG_READNOTWRITE | + SEQ_CFG_CSDEASSERT | + SEQ_CFG_STARTSEQ), +}; + static inline int stfsm_is_idle(struct stfsm *fsm) { return readl(fsm->base + SPI_FAST_SEQ_STA) & 0x10; @@ -338,6 +354,42 @@ static void stfsm_read_fifo(struct stfsm *fsm, uint32_t *buf, } } +static void stfsm_read_jedec(struct stfsm *fsm, uint8_t *const jedec) +{ + const struct stfsm_seq *seq = &stfsm_seq_read_jedec; + uint32_t tmp[2]; + + stfsm_load_seq(fsm, seq); + + stfsm_read_fifo(fsm, tmp, 8); + + memcpy(jedec, tmp, 5); + + stfsm_wait_seq(fsm); +} + +static struct flash_info *stfsm_jedec_probe(struct stfsm *fsm) +{ + u16 ext_jedec; + u32 jedec; + u8 id[5]; + + stfsm_read_jedec(fsm, id); + + jedec = id[0] << 16 | id[1] << 8 | id[2]; + /* + * JEDEC also defines an optional "extended device information" + * string for after vendor-specific data, after the three bytes + * we use here. Supporting some chips might require using it. + */ + ext_jedec = id[3] << 8 | id[4]; + + dev_dbg(fsm->dev, "JEDEC = 0x%08x [%02x %02x %02x %02x %02x]\n", + jedec, id[0], id[1], id[2], id[3], id[4]); + + return NULL; +} + static int stfsm_set_mode(struct stfsm *fsm, uint32_t mode) { int ret, timeout = 10; @@ -474,6 +526,9 @@ static int stfsm_probe(struct platform_device *pdev) return ret; } + /* Detect SPI FLASH device */ + stfsm_jedec_probe(fsm); + platform_set_drvdata(pdev, fsm); fsm->mtd.dev.parent = &pdev->dev; -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/