From 7830c0ef26cb73b653c2db2f3ca7be08f44fa046 Mon Sep 17 00:00:00 2001 From: Dinh Nguyen Date: Fri, 29 May 2020 10:58:05 -0500 Subject: [PATCH] spi: dw: add reset control Add mechanism to get the reset control and deassert it in order to bring the IP out of reset. Signed-off-by: Liang Jin J Signed-off-by: Dinh Nguyen Link: https://lore.kernel.org/r/20200529155806.16758-1-dinguyen@kernel.org Signed-off-by: Mark Brown --- drivers/spi/spi-dw-mmio.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/spi/spi-dw-mmio.c b/drivers/spi/spi-dw-mmio.c index 0894b4c..a1b87d4 100644 --- a/drivers/spi/spi-dw-mmio.c +++ b/drivers/spi/spi-dw-mmio.c @@ -19,6 +19,7 @@ #include #include #include +#include #include "spi-dw.h" @@ -29,6 +30,7 @@ struct dw_spi_mmio { struct clk *clk; struct clk *pclk; void *priv; + struct reset_control *rstc; }; #define MSCC_CPU_SYSTEM_CTRL_GENERAL_CTRL 0x24 @@ -224,6 +226,14 @@ static int dw_spi_mmio_probe(struct platform_device *pdev) if (ret) goto out_clk; + /* find an optional reset controller */ + dwsmmio->rstc = devm_reset_control_get_optional_exclusive(&pdev->dev, "spi"); + if (IS_ERR(dwsmmio->rstc)) { + ret = PTR_ERR(dwsmmio->rstc); + goto out_clk; + } + reset_control_deassert(dwsmmio->rstc); + dws->bus_num = pdev->id; dws->max_freq = clk_get_rate(dwsmmio->clk); @@ -257,6 +267,8 @@ out: clk_disable_unprepare(dwsmmio->pclk); out_clk: clk_disable_unprepare(dwsmmio->clk); + reset_control_assert(dwsmmio->rstc); + return ret; } @@ -268,6 +280,7 @@ static int dw_spi_mmio_remove(struct platform_device *pdev) pm_runtime_disable(&pdev->dev); clk_disable_unprepare(dwsmmio->pclk); clk_disable_unprepare(dwsmmio->clk); + reset_control_assert(dwsmmio->rstc); return 0; } -- 2.7.4