[PATCHv2 8/8] ata: sata_dwc_460ex: use devm for old DMA resource lifetime management

[Rosen Penev <rosenp@gmail.com>]

Convert sata_dwc_dma_exit_old() to a devm action callback and register
it via devm_add_action_or_reset() after dw_dma_probe() succeeds.  This
lets the devm framework handle DMA controller teardown automatically on
probe failure and driver removal.

As a result the probe function can use plain return-on-error for all
failure paths - the dma_initialized flag, the goto labels, and the
explicit sata_dwc_dma_exit_old() call in sata_dwc_remove() are all
eliminated.

Assisted-by: opencode:big-pickle
Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 drivers/ata/sata_dwc_460ex.c | 34 +++++++++++++---------------------
 1 file changed, 13 insertions(+), 21 deletions(-)

diff --git a/drivers/ata/sata_dwc_460ex.c b/drivers/ata/sata_dwc_460ex.c
index e8e2790be1d6..352cd7f02163 100644
--- a/drivers/ata/sata_dwc_460ex.c
+++ b/drivers/ata/sata_dwc_460ex.c
@@ -222,10 +222,18 @@ static int sata_dwc_dma_get_channel_old(struct sata_dwc_device_port *hsdevp)
 	return 0;
 }
 
+static void sata_dwc_dma_exit_old(void *data)
+{
+	struct sata_dwc_device *hsdev = data;
+
+	dw_dma_remove(hsdev->dma);
+}
+
 static int sata_dwc_dma_init_old(struct platform_device *pdev,
 				 struct sata_dwc_device *hsdev)
 {
 	struct device *dev = &pdev->dev;
+	int err;
 
 	hsdev->dma = devm_kzalloc(dev, sizeof(*hsdev->dma), GFP_KERNEL);
 	if (!hsdev->dma)
@@ -245,15 +253,11 @@ static int sata_dwc_dma_init_old(struct platform_device *pdev,
 		return PTR_ERR(hsdev->dma->regs);
 
 	/* Initialize AHB DMAC */
-	return dw_dma_probe(hsdev->dma);
-}
-
-static void sata_dwc_dma_exit_old(struct sata_dwc_device *hsdev)
-{
-	if (!hsdev->dma)
-		return;
+	err = dw_dma_probe(hsdev->dma);
+	if (err)
+		return err;
 
-	dw_dma_remove(hsdev->dma);
+	return devm_add_action_or_reset(dev, sata_dwc_dma_exit_old, hsdev);
 }
 
 #endif
@@ -1203,19 +1207,12 @@ static int sata_dwc_probe(struct platform_device *ofdev)
 	err = ata_host_activate(host, irq, sata_dwc_isr, 0, &sata_dwc_sht);
 	if (err) {
 		dev_err(dev, "failed to activate host");
-		goto error_out;
+		return err;
 	}
 
 	/* Enable SATA Interrupts */
 	sata_dwc_enable_interrupts(hsdev);
 	return 0;
-
-error_out:
-#ifdef CONFIG_SATA_DWC_OLD_DMA
-	if (!device_property_present(dev, "dmas"))
-		sata_dwc_dma_exit_old(hsdev);
-#endif
-	return err;
 }
 
 static void sata_dwc_remove(struct platform_device *ofdev)
@@ -1228,11 +1225,6 @@ static void sata_dwc_remove(struct platform_device *ofdev)
 
 	ata_host_detach(host);
 
-#ifdef CONFIG_SATA_DWC_OLD_DMA
-	/* Free SATA DMA resources */
-	sata_dwc_dma_exit_old(hsdev);
-#endif
-
 	dev_dbg(dev, "done\n");
 }
 
-- 
2.55.0