[PATCH 07/17] i3c: mipi-i3c-hci: Manage DMA deallocation via devres action

[Adrian Hunter]

The driver already uses devres for resource management, but the standard
resource-managed DMA allocation helpers cannot be used because they assume
the DMA device matches the managed device.

To address this, factor out the deallocation logic from hci_dma_cleanup()
into a new helper, hci_dma_free(), and register it as a devres action.

Signed-off-by: Adrian Hunter <adrian.hunter at intel.com>
---
 drivers/i3c/master/mipi-i3c-hci/dma.c | 53 ++++++++++++++++++---------
 1 file changed, 36 insertions(+), 17 deletions(-)

diff --git a/drivers/i3c/master/mipi-i3c-hci/dma.c b/drivers/i3c/master/mipi-i3c-hci/dma.c
index 54849aa98fad..703d5cf79d5e 100644
--- a/drivers/i3c/master/mipi-i3c-hci/dma.c
+++ b/drivers/i3c/master/mipi-i3c-hci/dma.c
@@ -146,30 +146,18 @@ struct hci_dma_dev_ibi_data {
 	unsigned int max_len;
 };
 
-static void hci_dma_cleanup(struct i3c_hci *hci)
+static void hci_dma_free(void *data)
 {
+	struct i3c_hci *hci = data;
 	struct hci_rings_data *rings = hci->io_data;
 	struct hci_rh_data *rh;
-	unsigned int i;
 
 	if (!rings)
 		return;
 
-	for (i = 0; i < rings->total; i++) {
-		rh = &rings->headers[i];
-
-		rh_reg_write(INTR_SIGNAL_ENABLE, 0);
-		rh_reg_write(RING_CONTROL, 0);
-	}
-
-	i3c_hci_sync_irq_inactive(hci);
-
-	for (i = 0; i < rings->total; i++) {
+	for (int i = 0; i < rings->total; i++) {
 		rh = &rings->headers[i];
 
-		rh_reg_write(CR_SETUP, 0);
-		rh_reg_write(IBI_SETUP, 0);
-
 		if (rh->xfer)
 			dma_free_coherent(rings->sysdev,
 					  rh->xfer_struct_sz * rh->xfer_entries,
@@ -190,12 +178,38 @@ static void hci_dma_cleanup(struct i3c_hci *hci)
 		kfree(rh->ibi_data);
 	}
 
-	rhs_reg_write(CONTROL, 0);
-
 	kfree(rings);
 	hci->io_data = NULL;
 }
 
+static void hci_dma_cleanup(struct i3c_hci *hci)
+{
+	struct hci_rings_data *rings = hci->io_data;
+	struct hci_rh_data *rh;
+	unsigned int i;
+
+	if (!rings)
+		return;
+
+	for (i = 0; i < rings->total; i++) {
+		rh = &rings->headers[i];
+
+		rh_reg_write(INTR_SIGNAL_ENABLE, 0);
+		rh_reg_write(RING_CONTROL, 0);
+	}
+
+	i3c_hci_sync_irq_inactive(hci);
+
+	for (i = 0; i < rings->total; i++) {
+		rh = &rings->headers[i];
+
+		rh_reg_write(CR_SETUP, 0);
+		rh_reg_write(IBI_SETUP, 0);
+	}
+
+	rhs_reg_write(CONTROL, 0);
+}
+
 static int hci_dma_init(struct i3c_hci *hci)
 {
 	struct hci_rings_data *rings;
@@ -359,10 +373,15 @@ static int hci_dma_init(struct i3c_hci *hci)
 					   RING_CTRL_RUN_STOP);
 	}
 
+	ret = devm_add_action(hci->master.dev.parent, hci_dma_free, hci);
+	if (ret)
+		goto err_out;
+
 	return 0;
 
 err_out:
 	hci_dma_cleanup(hci);
+	hci_dma_free(hci);
 	return ret;
 }
 
-- 
2.51.0