dmaengine: tegra: Return correct DMA status when paused

Currently, the driver does not return the correct DMA status when a DMA
pause is issued by the client drivers. This causes GPCDMA users to
assume that DMA is still running, while in reality, the DMA is paused.

Return DMA_PAUSED for tx_status() if the channel is paused in the middle
of a transfer.

Fixes: ee17028009d4 ("dmaengine: tegra: Add tegra gpcdma driver")
Cc: [e-mail]
Signed-off-by: Akhil R <[e-mail]>
Signed-off-by: Kartik Rajput <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

drivers/dma/tegra186-gpc-dma.c

···
 	bool config_init;
 	char name[30];
 	enum dma_transfer_direction sid_dir;
+	enum dma_status status;
 	int id;
 	int irq;
 	int slave_id;
···
 		tegra_dma_dump_chan_regs(tdc);
 	}
 
+	tdc->status = DMA_PAUSED;
+
 	return ret;
 }
 
···
 	val = tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSRE);
 	val &= ~TEGRA_GPCDMA_CHAN_CSRE_PAUSE;
 	tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSRE, val);
+
+	tdc->status = DMA_IN_PROGRESS;
 }
 
 static int tegra_dma_device_resume(struct dma_chan *dc)
···
 
 	tegra_dma_sid_free(tdc);
 	tdc->dma_desc = NULL;
+	tdc->status = DMA_COMPLETE;
 }
 
 static void tegra_dma_chan_decode_error(struct tegra_dma_channel *tdc,
···
 		tdc->dma_desc = NULL;
 	}
 
+	tdc->status = DMA_COMPLETE;
 	tegra_dma_sid_free(tdc);
 	vchan_get_all_descriptors(&tdc->vc, &head);
 	spin_unlock_irqrestore(&tdc->vc.lock, flags);
···
 	ret = dma_cookie_status(dc, cookie, txstate);
 	if (ret == DMA_COMPLETE)
 		return ret;
+
+	if (tdc->status == DMA_PAUSED)
+		ret = DMA_PAUSED;
 
 	spin_lock_irqsave(&tdc->vc.lock, flags);
 	vd = vchan_find_desc(&tdc->vc, cookie);