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Message-Id: <20200521170359.20430-1-dinguyen@kernel.org>
Date: Thu, 21 May 2020 12:03:58 -0500
From: Dinh Nguyen <dinguyen@...nel.org>
To: linux-kernel@...r.kernel.org
Cc: dinguyen@...nel.org, devicetree@...r.kernel.org,
broonie@...nel.org, robh+dt@...nel.org, linux-spi@...r.kernel.org,
Liang Jin J <liang.j.jin@...csson.com>
Subject: [PATCH 1/2] 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@...csson.com>
Signed-off-by: Dinh Nguyen <dinguyen@...nel.org>
---
drivers/spi/spi-dw-mmio.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/drivers/spi/spi-dw-mmio.c b/drivers/spi/spi-dw-mmio.c
index 384a3ab6dc2d..5c813e15ed89 100644
--- a/drivers/spi/spi-dw-mmio.c
+++ b/drivers/spi/spi-dw-mmio.c
@@ -20,6 +20,7 @@
#include <linux/acpi.h>
#include <linux/property.h>
#include <linux/regmap.h>
+#include <linux/reset.h>
#include "spi-dw.h"
@@ -30,6 +31,7 @@ struct dw_spi_mmio {
struct clk *clk;
struct clk *pclk;
void *priv;
+ struct reset_control *rstc;
};
#define MSCC_CPU_SYSTEM_CTRL_GENERAL_CTRL 0x24
@@ -145,6 +147,10 @@ static int dw_spi_mmio_probe(struct platform_device *pdev)
if (!dwsmmio)
return -ENOMEM;
+ dwsmmio->rstc = devm_reset_control_get_exclusive(&pdev->dev, "spi");
+ if (!IS_ERR(dwsmmio->rstc))
+ reset_control_deassert(dwsmmio->rstc);
+
dws = &dwsmmio->dws;
/* Get basic io resource and map it */
@@ -220,6 +226,9 @@ static int dw_spi_mmio_remove(struct platform_device *pdev)
clk_disable_unprepare(dwsmmio->pclk);
clk_disable_unprepare(dwsmmio->clk);
+ if (dwsmmio->rstc)
+ reset_control_assert(dwsmmio->rstc);
+
return 0;
}
--
2.17.1
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