From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan Agner Subject: [PATCH] spi: imx: do not access registers while clocks disabled Date: Sun, 7 Jan 2018 15:05:49 +0100 Message-ID: <20180107140549.17855-1-stefan@agner.ch> Cc: linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Stefan Agner , Philippe De Muyter , Huang Shijie To: broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org Return-path: Sender: linux-spi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Since clocks are disabled except during message transfer clocks are also disabled when spi_imx_remove gets called. Accessing registers leads to a freeeze at least on a i.MX 6ULL. Enable clocks before disabling accessing the MXC_CSPICTRL register. Fixes: 9e556dcc55774 ("spi: spi-imx: only enable the clocks when we start to transfer a message") Cc: Philippe De Muyter Cc: Huang Shijie Signed-off-by: Stefan Agner --- drivers/spi/spi-imx.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index 79ddefe4180d..40390d31a93b 100644 --- a/drivers/spi/spi-imx.c +++ b/drivers/spi/spi-imx.c @@ -1668,12 +1668,23 @@ static int spi_imx_remove(struct platform_device *pdev) { struct spi_master *master = platform_get_drvdata(pdev); struct spi_imx_data *spi_imx = spi_master_get_devdata(master); + int ret; spi_bitbang_stop(&spi_imx->bitbang); + ret = clk_enable(spi_imx->clk_per); + if (ret) + return ret; + + ret = clk_enable(spi_imx->clk_ipg); + if (ret) { + clk_disable(spi_imx->clk_per); + return ret; + } + writel(0, spi_imx->base + MXC_CSPICTRL); - clk_unprepare(spi_imx->clk_ipg); - clk_unprepare(spi_imx->clk_per); + clk_disable_unprepare(spi_imx->clk_ipg); + clk_disable_unprepare(spi_imx->clk_per); spi_imx_sdma_exit(spi_imx); spi_master_put(master); -- 2.15.1 -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html