clk: sunxi: sun9i-mmc: Implement reset callback for reset controls

commit 61d2f2a upstream. Our MMC host driver now issues a reset, instead of just deasserting the reset control, since commit c34eda6 ("mmc: sunxi: Reset the device at probe time"). The sun9i-mmc clock driver does not support this, and will fail, which results in MMC not probing. This patch implements the reset callback by asserting the reset control, then deasserting it after a small delay. Fixes: 7a6fca8 ("clk: sunxi: Add driver for A80 MMC config clocks/resets") Signed-off-by: Chen-Yu Tsai <[email protected]> Acked-by: Philipp Zabel <[email protected]> Acked-by: Maxime Ripard <[email protected]> Signed-off-by: Michael Turquette <[email protected]> Link: lkml.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
TechNexion · Dec 29, 2017 · 2635a64 · 2635a64
1 parent 18276e9
commit 2635a64
Showing 1 changed file with 12 additions and 0 deletions.
diff --git a/drivers/clk/sunxi/clk-sun9i-mmc.c b/drivers/clk/sunxi/clk-sun9i-mmc.c
@@ -16,6 +16,7 @@
 
 #include <linux/clk.h>
 #include <linux/clk-provider.h>
+#include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
@@ -83,9 +84,20 @@ static int sun9i_mmc_reset_deassert(struct reset_controller_dev *rcdev,
 	return 0;
 }
 
+static int sun9i_mmc_reset_reset(struct reset_controller_dev *rcdev,
+				 unsigned long id)
+{
+	sun9i_mmc_reset_assert(rcdev, id);
+	udelay(10);
+	sun9i_mmc_reset_deassert(rcdev, id);
+
+	return 0;
+}
+
 static const struct reset_control_ops sun9i_mmc_reset_ops = {
 	.assert		= sun9i_mmc_reset_assert,
 	.deassert	= sun9i_mmc_reset_deassert,
+	.reset		= sun9i_mmc_reset_reset,
 };
 
 static int sun9i_a80_mmc_config_clk_probe(struct platform_device *pdev)