From 98c8dccf2b2771fb622d449b2ec1604fc5d260e5 Mon Sep 17 00:00:00 2001 From: Nicolas Boichat Date: Mon, 9 Nov 2015 12:14:51 +0800 Subject: spi: mediatek: single device does not require cs_gpios When only one device is present, it is not necessary to specify cs_gpios, as the CS line can be controlled by the hardware module. Without this patch, older device tree bindings used before 37457607 "spi: mediatek: mt8173 spi multiple devices support" would cause a panic on boot. This fixes the crash, and re-introduces backward compatibility. Signed-off-by: Nicolas Boichat Acked-by: Leilk Liu Signed-off-by: Mark Brown --- drivers/spi/spi-mt65xx.c | 26 ++++++++++++++++++-------- 1 file changed, 18 insertions(+), 8 deletions(-) (limited to 'drivers/spi') diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c index 563954a61424..7840067062a8 100644 --- a/drivers/spi/spi-mt65xx.c +++ b/drivers/spi/spi-mt65xx.c @@ -410,7 +410,7 @@ static int mtk_spi_setup(struct spi_device *spi) if (!spi->controller_data) spi->controller_data = (void *)&mtk_default_chip_info; - if (mdata->dev_comp->need_pad_sel) + if (mdata->dev_comp->need_pad_sel && gpio_is_valid(spi->cs_gpio)) gpio_direction_output(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH)); return 0; @@ -632,13 +632,23 @@ static int mtk_spi_probe(struct platform_device *pdev) goto err_put_master; } - for (i = 0; i < master->num_chipselect; i++) { - ret = devm_gpio_request(&pdev->dev, master->cs_gpios[i], - dev_name(&pdev->dev)); - if (ret) { - dev_err(&pdev->dev, - "can't get CS GPIO %i\n", i); - goto err_put_master; + if (!master->cs_gpios && master->num_chipselect > 1) { + dev_err(&pdev->dev, + "cs_gpios not specified and num_chipselect > 1\n"); + ret = -EINVAL; + goto err_put_master; + } + + if (master->cs_gpios) { + for (i = 0; i < master->num_chipselect; i++) { + ret = devm_gpio_request(&pdev->dev, + master->cs_gpios[i], + dev_name(&pdev->dev)); + if (ret) { + dev_err(&pdev->dev, + "can't get CS GPIO %i\n", i); + goto err_put_master; + } } } } -- cgit v1.2.3