diff options
| author | Dinh Nguyen <dinguyen@kernel.org> | 2020-05-29 10:58:05 -0500 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2020-05-29 17:49:55 +0100 |
| commit | 7830c0ef26cb73b653c2db2f3ca7be08f44fa046 (patch) | |
| tree | 96bc89027ad2fe21653a52a89f34dfae6be9a36b /drivers/spi | |
| parent | ecfbd3cf3b8bb73ac6a80ddf430b5912fd4402a6 (diff) | |
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 <liang.j.jin@ericsson.com>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Link: https://lore.kernel.org/r/20200529155806.16758-1-dinguyen@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-dw-mmio.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/drivers/spi/spi-dw-mmio.c b/drivers/spi/spi-dw-mmio.c index 0894b4c09496..a1b87d4606ba 100644 --- a/drivers/spi/spi-dw-mmio.c +++ b/drivers/spi/spi-dw-mmio.c @@ -19,6 +19,7 @@ #include <linux/acpi.h> #include <linux/property.h> #include <linux/regmap.h> +#include <linux/reset.h> #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; } |