Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758600AbXJKKNz (ORCPT ); Thu, 11 Oct 2007 06:13:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757281AbXJKKK6 (ORCPT ); Thu, 11 Oct 2007 06:10:58 -0400 Received: from nwd2mail10.analog.com ([137.71.25.55]:41864 "EHLO nwd2mail10.analog.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755110AbXJKKKw (ORCPT ); Thu, 11 Oct 2007 06:10:52 -0400 X-IronPort-AV: i="4.21,259,1188792000"; d="scan'208"; a="53762413:sNHT321809670" From: Bryan Wu To: dbrownell@users.sourceforge.net, spi-devel-general@lists.sourceforge.net, linux-kernel@vger.kernel.org, akpm@linux-foundation.org Cc: Sonic Zhang , Bryan Wu Subject: [PATCH 8/9] Blackfin SPI driver: Fix SPI driver to work with SPI flash ST25P16 on bf548 Date: Thu, 11 Oct 2007 18:10:40 +0800 Message-Id: <1192097441-24962-9-git-send-email-bryan.wu@analog.com> X-Mailer: git-send-email 1.5.3.4 In-Reply-To: <1192097441-24962-1-git-send-email-bryan.wu@analog.com> References: <1192097441-24962-1-git-send-email-bryan.wu@analog.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 12817 Lines: 437 From: Sonic Zhang Current SPI driver enables SPI controller and set the SPI baud register for each SPI transfer. But, they should never be changed within a SPI message session, in which seveal SPI transfers are pumped. This patch move move SPI setting to the begining of a message session. And never disables SPI controller until an error occurs. Signed-off-by: Sonic Zhang Signed-off-by: Bryan Wu --- drivers/spi/spi_bfin5xx.c | 162 ++++++++++++++++++++++++--------------------- 1 files changed, 87 insertions(+), 75 deletions(-) diff --git a/drivers/spi/spi_bfin5xx.c b/drivers/spi/spi_bfin5xx.c index c1516cb..0cdfc2b 100644 --- a/drivers/spi/spi_bfin5xx.c +++ b/drivers/spi/spi_bfin5xx.c @@ -222,9 +222,13 @@ static int restore_state(struct driver_data *drv_data) dev_dbg(&drv_data->pdev->dev, "restoring spi ctl state\n"); /* Load the registers */ - write_CTRL(chip->ctl_reg); + cs_deactive(chip); write_BAUD(chip->baud); - cs_active(chip); + chip->ctl_reg &= (~BIT_CTL_TIMOD); + chip->ctl_reg |= (chip->width << 8); + write_CTRL(chip->ctl_reg); + + bfin_spi_enable(drv_data); if (ret) dev_dbg(&drv_data->pdev->dev, @@ -271,6 +275,7 @@ static void u8_writer(struct driver_data *drv_data) { dev_dbg(&drv_data->pdev->dev, "cr8-s is 0x%x\n", read_STAT()); + while (drv_data->tx < drv_data->tx_end) { write_TDBR(*(u8 *) (drv_data->tx)); while (read_STAT() & BIT_STAT_TXS) @@ -293,16 +298,16 @@ static void u8_cs_chg_writer(struct driver_data *drv_data) write_TDBR(*(u8 *) (drv_data->tx)); while (read_STAT() & BIT_STAT_TXS) continue; - while (!(read_STAT() & BIT_STAT_SPIF)) - continue; cs_deactive(chip); if (chip->cs_chg_udelay) udelay(chip->cs_chg_udelay); ++drv_data->tx; } - cs_deactive(chip); + /* poll for SPI completion before returning */ + while (!(read_STAT() & BIT_STAT_SPIF)) + continue; } static void u8_reader(struct driver_data *drv_data) @@ -314,6 +319,7 @@ static void u8_reader(struct driver_data *drv_data) write_TDBR(0xFFFF); dummy_read(); + while (drv_data->rx < drv_data->rx_end - 1) { while (!(read_STAT() & BIT_STAT_RXS)) continue; @@ -331,23 +337,30 @@ static void u8_cs_chg_reader(struct driver_data *drv_data) { struct chip_data *chip = drv_data->cur_chip; - while (drv_data->rx < drv_data->rx_end) { - cs_active(chip); + /* clear TDBR buffer before read(else it will be shifted out) */ + write_TDBR(0xFFFF); - read_RDBR(); /* kick off */ - while (!(read_STAT() & BIT_STAT_RXS)) - continue; - while (!(read_STAT() & BIT_STAT_SPIF)) - continue; - *(u8 *) (drv_data->rx) = read_SHAW(); + cs_active(chip); + dummy_read(); + + while (drv_data->rx < drv_data->rx_end - 1) { cs_deactive(chip); if (chip->cs_chg_udelay) udelay(chip->cs_chg_udelay); + + while (!(read_STAT() & BIT_STAT_RXS)) + continue; + cs_active(chip); + *(u8 *) (drv_data->rx) = read_RDBR(); ++drv_data->rx; } cs_deactive(chip); + while (!(read_STAT() & BIT_STAT_RXS)) + continue; + *(u8 *) (drv_data->rx) = read_SHAW(); + ++drv_data->rx; } static void u8_duplex(struct driver_data *drv_data) @@ -355,7 +368,7 @@ static void u8_duplex(struct driver_data *drv_data) /* in duplex mode, clk is triggered by writing of TDBR */ while (drv_data->rx < drv_data->rx_end) { write_TDBR(*(u8 *) (drv_data->tx)); - while (!(read_STAT() & BIT_STAT_SPIF)) + while (read_STAT() & BIT_STAT_TXS) continue; while (!(read_STAT() & BIT_STAT_RXS)) continue; @@ -363,6 +376,10 @@ static void u8_duplex(struct driver_data *drv_data) ++drv_data->rx; ++drv_data->tx; } + + /* poll for SPI completion before returning */ + while (!(read_STAT() & BIT_STAT_SPIF)) + continue; } static void u8_cs_chg_duplex(struct driver_data *drv_data) @@ -372,9 +389,8 @@ static void u8_cs_chg_duplex(struct driver_data *drv_data) while (drv_data->rx < drv_data->rx_end) { cs_active(chip); - write_TDBR(*(u8 *) (drv_data->tx)); - while (!(read_STAT() & BIT_STAT_SPIF)) + while (read_STAT() & BIT_STAT_TXS) continue; while (!(read_STAT() & BIT_STAT_RXS)) continue; @@ -386,7 +402,10 @@ static void u8_cs_chg_duplex(struct driver_data *drv_data) ++drv_data->rx; ++drv_data->tx; } - cs_deactive(chip); + + /* poll for SPI completion before returning */ + while (!(read_STAT() & BIT_STAT_SPIF)) + continue; } static void u16_writer(struct driver_data *drv_data) @@ -416,21 +435,26 @@ static void u16_cs_chg_writer(struct driver_data *drv_data) write_TDBR(*(u16 *) (drv_data->tx)); while ((read_STAT() & BIT_STAT_TXS)) continue; - while (!(read_STAT() & BIT_STAT_SPIF)) - continue; cs_deactive(chip); if (chip->cs_chg_udelay) udelay(chip->cs_chg_udelay); drv_data->tx += 2; } - cs_deactive(chip); + + /* poll for SPI completion before returning */ + while (!(read_STAT() & BIT_STAT_SPIF)) + continue; } static void u16_reader(struct driver_data *drv_data) { dev_dbg(&drv_data->pdev->dev, "cr-16 is 0x%x\n", read_STAT()); + + /* clear TDBR buffer before read(else it will be shifted out) */ + write_TDBR(0xFFFF); + dummy_read(); while (drv_data->rx < (drv_data->rx_end - 2)) { @@ -450,22 +474,30 @@ static void u16_cs_chg_reader(struct driver_data *drv_data) { struct chip_data *chip = drv_data->cur_chip; - while (drv_data->rx < drv_data->rx_end) { - cs_active(chip); + /* clear TDBR buffer before read(else it will be shifted out) */ + write_TDBR(0xFFFF); - read_RDBR(); /* kick off */ - while (!(read_STAT() & BIT_STAT_RXS)) - continue; - while (!(read_STAT() & BIT_STAT_SPIF)) - continue; - *(u16 *) (drv_data->rx) = read_SHAW(); + cs_active(chip); + dummy_read(); + + while (drv_data->rx < drv_data->rx_end) { cs_deactive(chip); if (chip->cs_chg_udelay) udelay(chip->cs_chg_udelay); + + while (!(read_STAT() & BIT_STAT_RXS)) + continue; + cs_active(chip); + *(u16 *) (drv_data->rx) = read_RDBR(); drv_data->rx += 2; } cs_deactive(chip); + + while (!(read_STAT() & BIT_STAT_RXS)) + continue; + *(u16 *) (drv_data->rx) = read_SHAW(); + drv_data->rx += 2; } static void u16_duplex(struct driver_data *drv_data) @@ -473,7 +505,7 @@ static void u16_duplex(struct driver_data *drv_data) /* in duplex mode, clk is triggered by writing of TDBR */ while (drv_data->tx < drv_data->tx_end) { write_TDBR(*(u16 *) (drv_data->tx)); - while (!(read_STAT() & BIT_STAT_SPIF)) + while (read_STAT() & BIT_STAT_TXS) continue; while (!(read_STAT() & BIT_STAT_RXS)) continue; @@ -481,6 +513,10 @@ static void u16_duplex(struct driver_data *drv_data) drv_data->rx += 2; drv_data->tx += 2; } + + /* poll for SPI completion before returning */ + while (!(read_STAT() & BIT_STAT_SPIF)) + continue; } static void u16_cs_chg_duplex(struct driver_data *drv_data) @@ -491,7 +527,7 @@ static void u16_cs_chg_duplex(struct driver_data *drv_data) cs_active(chip); write_TDBR(*(u16 *) (drv_data->tx)); - while (!(read_STAT() & BIT_STAT_SPIF)) + while (read_STAT() & BIT_STAT_TXS) continue; while (!(read_STAT() & BIT_STAT_RXS)) continue; @@ -503,7 +539,10 @@ static void u16_cs_chg_duplex(struct driver_data *drv_data) drv_data->rx += 2; drv_data->tx += 2; } - cs_deactive(chip); + + /* poll for SPI completion before returning */ + while (!(read_STAT() & BIT_STAT_SPIF)) + continue; } /* test if ther is more transfer to be done */ @@ -587,8 +626,6 @@ static irqreturn_t dma_irq_handler(int irq, void *dev_id) while (!(read_STAT() & SPIF)) continue; - bfin_spi_disable(drv_data); - msg->actual_length += drv_data->len_in_bytes; if (drv_data->cs_change) @@ -698,12 +735,8 @@ static void pump_transfers(unsigned long data) message->state = RUNNING_STATE; dma_config = 0; - /* restore spi status for each spi transfer */ - if (transfer->speed_hz) { - write_BAUD(hz_to_spi_baud(transfer->speed_hz)); - } else { - write_BAUD(chip->baud); - } + write_STAT(BIT_STAT_CLR); + cr = (read_CTRL() & (~BIT_CTL_TIMOD)); cs_active(chip); dev_dbg(&drv_data->pdev->dev, @@ -717,10 +750,8 @@ static void pump_transfers(unsigned long data) */ if (drv_data->cur_chip->enable_dma && drv_data->len > 6) { - write_STAT(BIT_STAT_CLR); disable_dma(spi_dma_ch); clear_dma_irqstat(spi_dma_ch); - bfin_spi_disable(drv_data); /* config dma channel */ dev_dbg(&drv_data->pdev->dev, "doing dma transfer\n"); @@ -734,14 +765,14 @@ static void pump_transfers(unsigned long data) dma_width = WDSIZE_8; } - /* set transfer width,direction. And enable spi */ - cr = (read_CTRL() & (~BIT_CTL_TIMOD)); - /* dirty hack for autobuffer DMA mode */ if (drv_data->tx_dma == 0xFFFF) { dev_dbg(&drv_data->pdev->dev, "doing autobuffer DMA out.\n"); + /* set SPI transfer mode */ + write_CTRL(cr | CFG_SPI_DMAWRITE); + /* no irq in autobuffer mode */ dma_config = (DMAFLOW_AUTO | RESTART | dma_width | DI_EN); @@ -749,8 +780,6 @@ static void pump_transfers(unsigned long data) set_dma_start_addr(spi_dma_ch, (unsigned long)drv_data->tx); enable_dma(spi_dma_ch); - write_CTRL(cr | CFG_SPI_DMAWRITE | (width << 8) | - (CFG_SPI_ENABLE << 14)); /* just return here, there can only be one transfer in this mode */ message->status = 0; @@ -763,11 +792,11 @@ static void pump_transfers(unsigned long data) /* set transfer mode, and enable SPI */ dev_dbg(&drv_data->pdev->dev, "doing DMA in.\n"); - /* disable SPI before write to TDBR */ - write_CTRL(cr & ~BIT_CTL_ENABLE); + /* set SPI transfer mode */ + write_CTRL(cr | CFG_SPI_DMAREAD); /* clear tx reg soformer data is not shifted out */ - write_TDBR(0xFF); + write_TDBR(0xFFFF); set_dma_x_count(spi_dma_ch, drv_data->len); @@ -779,14 +808,12 @@ static void pump_transfers(unsigned long data) (unsigned long)drv_data->rx); enable_dma(spi_dma_ch); - cr |= - CFG_SPI_DMAREAD | (width << 8) | (CFG_SPI_ENABLE << - 14); - /* set transfer mode, and enable SPI */ - write_CTRL(cr); } else if (drv_data->tx != NULL) { dev_dbg(&drv_data->pdev->dev, "doing DMA out.\n"); + /* set SPI transfer mode */ + write_CTRL(cr | CFG_SPI_DMAWRITE); + /* start dma */ dma_enable_irq(spi_dma_ch); dma_config = (RESTART | dma_width | DI_EN); @@ -794,28 +821,20 @@ static void pump_transfers(unsigned long data) set_dma_start_addr(spi_dma_ch, (unsigned long)drv_data->tx); enable_dma(spi_dma_ch); - - write_CTRL(cr | CFG_SPI_DMAWRITE | (width << 8) | - (CFG_SPI_ENABLE << 14)); - } } else { /* IO mode write then read */ dev_dbg(&drv_data->pdev->dev, "doing IO transfer\n"); - write_STAT(BIT_STAT_CLR); - if (drv_data->tx != NULL && drv_data->rx != NULL) { /* full duplex mode */ BUG_ON((drv_data->tx_end - drv_data->tx) != (drv_data->rx_end - drv_data->rx)); - cr = (read_CTRL() & (~BIT_CTL_TIMOD)); - cr |= CFG_SPI_WRITE | (width << 8) | - (CFG_SPI_ENABLE << 14); dev_dbg(&drv_data->pdev->dev, "IO duplex: cr is 0x%x\n", cr); - write_CTRL(cr); + /* set SPI transfer mode */ + write_CTRL(cr | CFG_SPI_WRITE); drv_data->duplex(drv_data); @@ -823,13 +842,11 @@ static void pump_transfers(unsigned long data) tranf_success = 0; } else if (drv_data->tx != NULL) { /* write only half duplex */ - cr = (read_CTRL() & (~BIT_CTL_TIMOD)); - cr |= CFG_SPI_WRITE | (width << 8) | - (CFG_SPI_ENABLE << 14); dev_dbg(&drv_data->pdev->dev, "IO write: cr is 0x%x\n", cr); - write_CTRL(cr); + /* set SPI transfer mode */ + write_CTRL(cr | CFG_SPI_WRITE); drv_data->write(drv_data); @@ -837,13 +854,11 @@ static void pump_transfers(unsigned long data) tranf_success = 0; } else if (drv_data->rx != NULL) { /* read only half duplex */ - cr = (read_CTRL() & (~BIT_CTL_TIMOD)); - cr |= CFG_SPI_READ | (width << 8) | - (CFG_SPI_ENABLE << 14); dev_dbg(&drv_data->pdev->dev, "IO read: cr is 0x%x\n", cr); - write_CTRL(cr); + /* set SPI transfer mode */ + write_CTRL(cr | CFG_SPI_READ); drv_data->read(drv_data); if (drv_data->rx != drv_data->rx_end) @@ -858,9 +873,6 @@ static void pump_transfers(unsigned long data) /* Update total byte transfered */ message->actual_length += drv_data->len; - if (drv_data->cs_change) - cs_deactive(chip); - /* Move to next transfer of this msg */ message->state = next_transfer(drv_data); } -- 1.5.3.4 - 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/