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    SubjectRe: [PATCH 1/2] spi: dw: add reset control
    On Thu, May 21, 2020 at 12:03:58PM -0500, Dinh Nguyen wrote:
    > 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>

    Is the From: correct here?

    Also adding everyone else who's got patches in flight for this driver
    right now.

    > ---
    > 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 */

    Should we also undo the reset in error paths from probe()? It's not the
    end of the world if we don't but...

    > @@ -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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