From 62310e51ac10c5e50998240e49a84d2e28377a48 Mon Sep 17 00:00:00 2001 From: Bryan Wu Date: Tue, 4 Dec 2007 23:45:20 -0800 Subject: [PATCH] spi: spi_bfin: update handling of delay-after-deselect Move cs_chg_udelay handling (specific to this driver) to cs_deactive(), fixing a bug when some SPI LCD driver needs delay after cs_deactive. Fix bug reported by Cameron Barfield https://blackfin.uclinux.org/gf/project/uclinux-dist/forum/?action=ForumBrowse&forum_id=39&_forum_action=ForumMessageBrowse&thread_id=23630&feedback=Message%20replied. Cc: Cameron Barfield Signed-off-by: Bryan Wu Signed-off-by: David Brownell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/spi/spi_bfin5xx.c | 24 +++++++++--------------- include/asm-blackfin/bfin5xx_spi.h | 2 +- 2 files changed, 10 insertions(+), 16 deletions(-) diff --git a/drivers/spi/spi_bfin5xx.c b/drivers/spi/spi_bfin5xx.c index 25b0efc5910..4dc7e674932 100644 --- a/drivers/spi/spi_bfin5xx.c +++ b/drivers/spi/spi_bfin5xx.c @@ -132,7 +132,7 @@ struct chip_data { u8 enable_dma; u8 bits_per_word; /* 8 or 16 */ u8 cs_change_per_word; - u8 cs_chg_udelay; + u16 cs_chg_udelay; /* Some devices require > 255usec delay */ void (*write) (struct driver_data *); void (*read) (struct driver_data *); void (*duplex) (struct driver_data *); @@ -211,6 +211,10 @@ static void cs_deactive(struct driver_data *drv_data, struct chip_data *chip) flag |= (chip->flag << 8); write_FLAG(drv_data, flag); + + /* Move delay here for consistency */ + if (chip->cs_chg_udelay) + udelay(chip->cs_chg_udelay); } #define MAX_SPI_SSEL 7 @@ -307,10 +311,9 @@ static void u8_cs_chg_writer(struct driver_data *drv_data) write_TDBR(drv_data, (*(u8 *) (drv_data->tx))); while (read_STAT(drv_data) & BIT_STAT_TXS) continue; + cs_deactive(drv_data, chip); - if (chip->cs_chg_udelay) - udelay(chip->cs_chg_udelay); ++drv_data->tx; } } @@ -359,9 +362,6 @@ static void u8_cs_chg_reader(struct driver_data *drv_data) while (drv_data->rx < drv_data->rx_end - 1) { cs_deactive(drv_data, chip); - if (chip->cs_chg_udelay) - udelay(chip->cs_chg_udelay); - while (!(read_STAT(drv_data) & BIT_STAT_RXS)) continue; cs_active(drv_data, chip); @@ -412,10 +412,9 @@ static void u8_cs_chg_duplex(struct driver_data *drv_data) while (!(read_STAT(drv_data) & BIT_STAT_RXS)) continue; *(u8 *) (drv_data->rx) = read_RDBR(drv_data); + cs_deactive(drv_data, chip); - if (chip->cs_chg_udelay) - udelay(chip->cs_chg_udelay); ++drv_data->rx; ++drv_data->tx; } @@ -452,10 +451,9 @@ static void u16_cs_chg_writer(struct driver_data *drv_data) write_TDBR(drv_data, (*(u16 *) (drv_data->tx))); while ((read_STAT(drv_data) & BIT_STAT_TXS)) continue; + cs_deactive(drv_data, chip); - if (chip->cs_chg_udelay) - udelay(chip->cs_chg_udelay); drv_data->tx += 2; } } @@ -504,9 +502,6 @@ static void u16_cs_chg_reader(struct driver_data *drv_data) while (drv_data->rx < drv_data->rx_end - 2) { cs_deactive(drv_data, chip); - if (chip->cs_chg_udelay) - udelay(chip->cs_chg_udelay); - while (!(read_STAT(drv_data) & BIT_STAT_RXS)) continue; cs_active(drv_data, chip); @@ -557,10 +552,9 @@ static void u16_cs_chg_duplex(struct driver_data *drv_data) while (!(read_STAT(drv_data) & BIT_STAT_RXS)) continue; *(u16 *) (drv_data->rx) = read_RDBR(drv_data); + cs_deactive(drv_data, chip); - if (chip->cs_chg_udelay) - udelay(chip->cs_chg_udelay); drv_data->rx += 2; drv_data->tx += 2; } diff --git a/include/asm-blackfin/bfin5xx_spi.h b/include/asm-blackfin/bfin5xx_spi.h index f617d876545..d4485b37d8e 100644 --- a/include/asm-blackfin/bfin5xx_spi.h +++ b/include/asm-blackfin/bfin5xx_spi.h @@ -162,7 +162,7 @@ struct bfin5xx_spi_chip { u8 enable_dma; u8 bits_per_word; u8 cs_change_per_word; - u8 cs_chg_udelay; + u16 cs_chg_udelay; /* Some devices require 16-bit delays */ }; #endif /* _SPI_CHANNEL_H_ */ -- 2.41.0