From cabb5b2a2866829177df2f1cee70f0dd42ee6ae0 Mon Sep 17 00:00:00 2001 From: Stefan Wahren Date: Tue, 25 Aug 2015 21:04:11 +0000 Subject: [PATCH] staging: fbtft: fix 9-bit SPI support detection MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Since the result of the setup function isn't adequate to check 9-bit SPI support, we better check bits_per_word_mask. Btw this change avoids a NULL pointer dereference with master drivers without a separate setup function. Signed-off-by: Stefan Wahren Acked-by: Noralf Trønnes Signed-off-by: Greg Kroah-Hartman --- drivers/staging/fbtft/fbtft-core.c | 10 +++------- drivers/staging/fbtft/flexfb.c | 11 ++++------- 2 files changed, 7 insertions(+), 14 deletions(-) diff --git a/drivers/staging/fbtft/fbtft-core.c b/drivers/staging/fbtft/fbtft-core.c index 23392eb..7f5fa3d 100644 --- a/drivers/staging/fbtft/fbtft-core.c +++ b/drivers/staging/fbtft/fbtft-core.c @@ -1436,15 +1436,11 @@ int fbtft_probe_common(struct fbtft_display *display, /* 9-bit SPI setup */ if (par->spi && display->buswidth == 9) { - par->spi->bits_per_word = 9; - ret = par->spi->master->setup(par->spi); - if (ret) { + if (par->spi->master->bits_per_word_mask & SPI_BPW_MASK(9)) { + par->spi->bits_per_word = 9; + } else { dev_warn(&par->spi->dev, "9-bit SPI not available, emulating using 8-bit.\n"); - par->spi->bits_per_word = 8; - ret = par->spi->master->setup(par->spi); - if (ret) - goto out_release; /* allocate buffer with room for dc bits */ par->extra = devm_kzalloc(par->info->device, par->txbuf.len + (par->txbuf.len / 8) + 8, diff --git a/drivers/staging/fbtft/flexfb.c b/drivers/staging/fbtft/flexfb.c index c763efc..3f380a0 100644 --- a/drivers/staging/fbtft/flexfb.c +++ b/drivers/staging/fbtft/flexfb.c @@ -463,15 +463,12 @@ static int flexfb_probe_common(struct spi_device *sdev, } par->fbtftops.write_register = fbtft_write_reg8_bus9; par->fbtftops.write_vmem = fbtft_write_vmem16_bus9; - sdev->bits_per_word = 9; - ret = sdev->master->setup(sdev); - if (ret) { + if (par->spi->master->bits_per_word_mask + & SPI_BPW_MASK(9)) { + par->spi->bits_per_word = 9; + } else { dev_warn(dev, "9-bit SPI not available, emulating using 8-bit.\n"); - sdev->bits_per_word = 8; - ret = sdev->master->setup(sdev); - if (ret) - goto out_release; /* allocate buffer with room for dc bits */ par->extra = devm_kzalloc(par->info->device, par->txbuf.len + (par->txbuf.len / 8) + 8, -- 2.7.4