media: hantro: Make struct hantro_variant.init() optional

The hantro_variant.init() function is there for platforms
to perform hardware-specific initialization, such as
clock rate bumping.

Not all platforms require it, so make it optional.
Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Tested-by: Alex Bee <knaerzche@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/staging/media/hantro/hantro.h

@@ -61,8 +61,8 @@ struct hantro_irq {
  * @num_postproc_fmts:		Number of post-processor formats.
  * @codec:			Supported codecs
  * @codec_ops:			Codec ops.
- * @init:			Initialize hardware.
- * @runtime_resume:		reenable hardware after power gating
+ * @init:			Initialize hardware, optional.
+ * @runtime_resume:		reenable hardware after power gating, optional.
  * @irqs:			array of irq names and interrupt handlers
  * @num_irqs:			number of irqs in the array
  * @clk_names:			array of clock names

drivers/staging/media/hantro/hantro_drv.c

@@ -942,11 +942,13 @@ static int hantro_probe(struct platform_device *pdev)
 		}
 	}
 
+	if (vpu->variant->init) {
 		ret = vpu->variant->init(vpu);
 		if (ret) {
 			dev_err(&pdev->dev, "Failed to init VPU hardware\n");
 			return ret;
 		}
+	}
 
 	pm_runtime_set_autosuspend_delay(vpu->dev, 100);
 	pm_runtime_use_autosuspend(vpu->dev);

drivers/staging/media/hantro/sama5d4_vdec_hw.c

@@ -64,11 +64,6 @@ static const struct hantro_fmt sama5d4_vdec_fmts[] = {
 	},
 };
 
-static int sama5d4_hw_init(struct hantro_dev *vpu)
-{
-	return 0;
-}
-
 /*
  * Supported codec ops.
  */
@@ -109,7 +104,6 @@ const struct hantro_variant sama5d4_vdec_variant = {
 	.codec = HANTRO_MPEG2_DECODER | HANTRO_VP8_DECODER |
 		 HANTRO_H264_DECODER,
 	.codec_ops = sama5d4_vdec_codec_ops,
-	.init = sama5d4_hw_init,
 	.irqs = sama5d4_irqs,
 	.num_irqs = ARRAY_SIZE(sama5d4_irqs),
 	.clk_names = sama5d4_clk_names,