iio: adc: meson_saradc: Fix memory allocation order

BugLink: https://bugs.launchpad.net/bugs/1851550
[ Upstream commit de10ac47597e7a3596b27631d0d5ce5f48d2c099 ]

meson_saradc's irq handler uses priv->regmap so make sure that it is
allocated before the irq get enabled.

This also fixes crash when CONFIG_DEBUG_SHIRQ is enabled, as device
managed resources are freed in the inverted order they had been
allocated, priv->regmap was freed before the spurious fake irq that
CONFIG_DEBUG_SHIRQ adds called the handler.

Fixes: 3af109131b7eb8 ("iio: adc: meson-saradc: switch from polling to interrupt mode")
Reported-by: Elie Roudninski <xademax@gmail.com>
Signed-off-by: Remi Pommarel <repk@triplefau.lt>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Tested-by: Elie ROUDNINSKI <xademax@gmail.com>
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Connor Kuehl <connor.kuehl@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/drivers/iio/adc/meson_saradc.c b/drivers/iio/adc/meson_saradc.c
index 7b28d045d2719f3e3a710eaa2ffce0e3183d561e..7b27306330a351f2edbee70f202d7110a79100b3 100644 (file)
--- a/drivers/iio/adc/meson_saradc.c
+++ b/drivers/iio/adc/meson_saradc.c
@@ -1219,6 +1219,11 @@ static int meson_sar_adc_probe(struct platform_device *pdev)
        if (IS_ERR(base))
                return PTR_ERR(base);
 
+       priv->regmap = devm_regmap_init_mmio(&pdev->dev, base,
+                                            priv->param->regmap_config);
+       if (IS_ERR(priv->regmap))
+               return PTR_ERR(priv->regmap);
+
        irq = irq_of_parse_and_map(pdev->dev.of_node, 0);
        if (!irq)
                return -EINVAL;
@@ -1228,11 +1233,6 @@ static int meson_sar_adc_probe(struct platform_device *pdev)
        if (ret)
                return ret;
 
-       priv->regmap = devm_regmap_init_mmio(&pdev->dev, base,
-                                            priv->param->regmap_config);
-       if (IS_ERR(priv->regmap))
-               return PTR_ERR(priv->regmap);
-
        priv->clkin = devm_clk_get(&pdev->dev, "clkin");
        if (IS_ERR(priv->clkin)) {
                dev_err(&pdev->dev, "failed to get clkin\n");