media: chips-media: wave5: support reset lines

Add initial support for optional reset lines. For now, simply deassert
resets while probing the driver and assert them back when removing the
driver.
Signed-off-by: Ivan Bornyakov <brnkv.i1@gmail.com>
Signed-off-by: Sebastian Fricke <sebastian.fricke@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

drivers/media/platform/chips-media/wave5/wave5-vpu.c

@@ -10,6 +10,7 @@
 #include <linux/clk.h>
 #include <linux/firmware.h>
 #include <linux/interrupt.h>
+#include <linux/reset.h>
 #include "wave5-vpu.h"
 #include "wave5-regdefine.h"
 #include "wave5-vpuconfig.h"
@@ -179,6 +180,16 @@ static int wave5_vpu_probe(struct platform_device *pdev)
 	dev_set_drvdata(&pdev->dev, dev);
 	dev->dev = &pdev->dev;
 
+	dev->resets = devm_reset_control_array_get_optional_exclusive(&pdev->dev);
+	if (IS_ERR(dev->resets)) {
+		return dev_err_probe(&pdev->dev, PTR_ERR(dev->resets),
+				     "Failed to get reset control\n");
+	}
+
+	ret = reset_control_deassert(dev->resets);
+	if (ret)
+		return dev_err_probe(&pdev->dev, ret, "Failed to deassert resets\n");
+
 	ret = devm_clk_bulk_get_all(&pdev->dev, &dev->clks);
 
 	/* continue without clock, assume externally managed */
@@ -191,7 +202,7 @@ static int wave5_vpu_probe(struct platform_device *pdev)
 	ret = clk_bulk_prepare_enable(dev->num_clks, dev->clks);
 	if (ret) {
 		dev_err(&pdev->dev, "Enabling clocks, fail: %d\n", ret);
-		return ret;
+		goto err_reset_assert;
 	}
 
 	ret = of_property_read_u32(pdev->dev.of_node, "sram-size",
@@ -282,6 +293,8 @@ static int wave5_vpu_probe(struct platform_device *pdev)
 	wave5_vdi_release(&pdev->dev);
 err_clk_dis:
 	clk_bulk_disable_unprepare(dev->num_clks, dev->clks);
+err_reset_assert:
+	reset_control_assert(dev->resets);
 
 	return ret;
 }
@@ -297,6 +310,7 @@ static void wave5_vpu_remove(struct platform_device *pdev)
 
 	mutex_destroy(&dev->dev_lock);
 	mutex_destroy(&dev->hw_lock);
+	reset_control_assert(dev->resets);
 	clk_bulk_disable_unprepare(dev->num_clks, dev->clks);
 	wave5_vpu_enc_unregister_device(dev);
 	wave5_vpu_dec_unregister_device(dev);

drivers/media/platform/chips-media/wave5/wave5-vpuapi.h

@@ -762,6 +762,7 @@ struct vpu_device {
 	struct kthread_worker *worker;
 	int vpu_poll_interval;
 	int num_clks;
+	struct reset_control *resets;
 };
 
 struct vpu_instance;