Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752950Ab0KXGWP (ORCPT ); Wed, 24 Nov 2010 01:22:15 -0500 Received: from cantor2.suse.de ([195.135.220.15]:45130 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752076Ab0KXGWN (ORCPT ); Wed, 24 Nov 2010 01:22:13 -0500 From: Takashi Iwai To: Chris Ball Cc: linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, Aries Lee , Takashi Iwai Subject: [PATCH 2/2] mmc: Test bus-width for old MMC devices Date: Wed, 24 Nov 2010 07:21:14 +0100 Message-Id: <1290579674-4616-3-git-send-email-tiwai@suse.de> X-Mailer: git-send-email 1.7.3.1 In-Reply-To: <1290579674-4616-1-git-send-email-tiwai@suse.de> References: <1290579674-4616-1-git-send-email-tiwai@suse.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5783 Lines: 208 From: Aries Lee Some old MMC devices fail with the 4/8 bits the driver tries to use exclusively. This patch adds a test for the given bus setup and falls back to the lower bit mode (until 1-bit mode) when the test fails. [Major rework and refactoring by tiwai] Signed-off-by: Aries Lee Signed-off-by: Takashi Iwai --- drivers/mmc/core/mmc.c | 49 ++++++++++++--------- drivers/mmc/core/mmc_ops.c | 102 ++++++++++++++++++++++++++++++++++++++++++++ drivers/mmc/core/mmc_ops.h | 1 + 3 files changed, 131 insertions(+), 21 deletions(-) diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index e81e6fe..5d8b4b2 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -507,29 +507,36 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, */ if ((card->csd.mmca_vsn >= CSD_SPEC_VER_4) && (host->caps & (MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA))) { - unsigned ext_csd_bit, bus_width; - - if (host->caps & MMC_CAP_8_BIT_DATA) { - ext_csd_bit = EXT_CSD_BUS_WIDTH_8; - bus_width = MMC_BUS_WIDTH_8; - } else { - ext_csd_bit = EXT_CSD_BUS_WIDTH_4; - bus_width = MMC_BUS_WIDTH_4; + static unsigned ext_csd_bits[] = { + EXT_CSD_BUS_WIDTH_8, + EXT_CSD_BUS_WIDTH_4, + EXT_CSD_BUS_WIDTH_1 + }; + static unsigned bus_widths[] = { + MMC_BUS_WIDTH_8, + MMC_BUS_WIDTH_4, + MMC_BUS_WIDTH_1 + }; + unsigned idx; + + if (host->caps & MMC_CAP_8_BIT_DATA) + idx = 0; + else + idx = 1; + for (; idx < ARRAY_SIZE(bus_widths); idx++) { + err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, + EXT_CSD_BUS_WIDTH, ext_csd_bits[idx]); + if (!err) { + mmc_set_bus_width(card->host, bus_widths[idx]); + err = mmc_bus_test(card, bus_widths[idx]); + if (!err) + break; + } } - - err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, - EXT_CSD_BUS_WIDTH, ext_csd_bit); - - if (err && err != -EBADMSG) - goto free_card; - if (err) { - printk(KERN_WARNING "%s: switch to bus width %d " - "failed\n", mmc_hostname(card->host), - 1 << bus_width); - err = 0; - } else { - mmc_set_bus_width(card->host, bus_width); + printk(KERN_WARNING "%s: switch to bus width failed\n", + mmc_hostname(card->host)); + goto free_card; } } diff --git a/drivers/mmc/core/mmc_ops.c b/drivers/mmc/core/mmc_ops.c index 326447c..f8f47f9 100644 --- a/drivers/mmc/core/mmc_ops.c +++ b/drivers/mmc/core/mmc_ops.c @@ -462,3 +462,105 @@ int mmc_send_status(struct mmc_card *card, u32 *status) return 0; } +#define MMC_CMD_BUS_TEST_W 19 +#define MMC_CMD_BUS_TEST_R 14 + +static int +mmc_send_bus_test(struct mmc_card *card, struct mmc_host *host, u8 opcode, + u8 len) +{ + struct mmc_request mrq; + struct mmc_command cmd; + struct mmc_data data; + struct scatterlist sg; + u8 *data_buf; + u8 *test_buf; + int i, err; + static u8 testdata_8bit[8] = { 0x55, 0xaa, 0, 0, 0, 0, 0, 0 }; + static u8 testdata_4bit[4] = { 0x5a, 0, 0, 0 }; + + /* dma onto stack is unsafe/nonportable, but callers to this + * routine normally provide temporary on-stack buffers ... + */ + data_buf = kmalloc(len, GFP_KERNEL); + if (!data_buf) + return -ENOMEM; + + if (len == 8) + test_buf = testdata_8bit; + else if (len == 4) + test_buf = testdata_4bit; + else { + printk(KERN_ERR "%s: Invaild bus_width %d\n", + mmc_hostname(host), len); + return -EINVAL; + } + + if (opcode == MMC_CMD_BUS_TEST_W) + memcpy(data_buf, test_buf, len); + + memset(&mrq, 0, sizeof(struct mmc_request)); + memset(&cmd, 0, sizeof(struct mmc_command)); + memset(&data, 0, sizeof(struct mmc_data)); + + mrq.cmd = &cmd; + mrq.data = &data; + cmd.opcode = opcode; + cmd.arg = 0; + + /* NOTE HACK: the MMC_RSP_SPI_R1 is always correct here, but we + * rely on callers to never use this with "native" calls for reading + * CSD or CID. Native versions of those commands use the R2 type, + * not R1 plus a data block. + */ + cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC; + + data.blksz = len; + data.blocks = 1; + if (opcode == MMC_CMD_BUS_TEST_R) + data.flags = MMC_DATA_READ; + else + data.flags = MMC_DATA_WRITE; + + data.sg = &sg; + data.sg_len = 1; + sg_init_one(&sg, data_buf, len); + mmc_wait_for_req(host, &mrq); + err = 0; + if (opcode == MMC_CMD_BUS_TEST_R) { + for (i = 0; i < len / 4; i++) + if ((test_buf[i] ^ data_buf[i]) != 0xff) { + err = -EIO; + break; + } + } + kfree(data_buf); + + if (cmd.error) + return cmd.error; + if (data.error) + return data.error; + + return err; +} + +int mmc_bus_test(struct mmc_card *card, u8 bus_width) +{ + int err, width; + + if (bus_width == MMC_BUS_WIDTH_8) + width = 8; + else if (bus_width == MMC_BUS_WIDTH_4) + width = 4; + else if (bus_width == MMC_BUS_WIDTH_1) + return 0; /* no need for test */ + else + return -EINVAL; + err = mmc_send_bus_test(card, card->host, MMC_CMD_BUS_TEST_W, width); + if (err < 0) + return err; + err = mmc_send_bus_test(card, card->host, MMC_CMD_BUS_TEST_R, width); + return err; + + +} diff --git a/drivers/mmc/core/mmc_ops.h b/drivers/mmc/core/mmc_ops.h index 653eb8e..e6d44b8 100644 --- a/drivers/mmc/core/mmc_ops.h +++ b/drivers/mmc/core/mmc_ops.h @@ -26,6 +26,7 @@ int mmc_send_cid(struct mmc_host *host, u32 *cid); int mmc_spi_read_ocr(struct mmc_host *host, int highcap, u32 *ocrp); int mmc_spi_set_crc(struct mmc_host *host, int use_crc); int mmc_card_sleepawake(struct mmc_host *host, int sleep); +int mmc_bus_test(struct mmc_card *card, u8 bus_width); #endif -- 1.7.3.1 -- 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/