[PATCH v6 3/5] usb: host: ohci-sm501: init genalloc for local memory

[laurentiu . tudor]

From: Laurentiu Tudor <laurentiu.tudor@xxxxxxx>

In preparation for dropping the existing "coherent" dma mem declaration
APIs, replace the current dma_declare_coherent_memory() based mechanism
with the creation of a genalloc pool that will be used in the OHCI
subsystem as replacement for the DMA APIs.

For context, see thread here: https://lkml.org/lkml/2019/4/22/357

Signed-off-by: Laurentiu Tudor <laurentiu.tudor@xxxxxxx>
---
 drivers/usb/host/ohci-sm501.c | 47 +++++++++++++++--------------------
 1 file changed, 20 insertions(+), 27 deletions(-)

diff --git a/drivers/usb/host/ohci-sm501.c b/drivers/usb/host/ohci-sm501.c
index c26228c25f99..b710e100aec9 100644
--- a/drivers/usb/host/ohci-sm501.c
+++ b/drivers/usb/host/ohci-sm501.c
@@ -110,40 +110,18 @@ static int ohci_hcd_sm501_drv_probe(struct platform_device *pdev)
 		goto err0;
 	}
 
-	/* The sm501 chip is equipped with local memory that may be used
-	 * by on-chip devices such as the video controller and the usb host.
-	 * This driver uses dma_declare_coherent_memory() to make sure
-	 * usb allocations with dma_alloc_coherent() allocate from
-	 * this local memory. The dma_handle returned by dma_alloc_coherent()
-	 * will be an offset starting from 0 for the first local memory byte.
-	 *
-	 * So as long as data is allocated using dma_alloc_coherent() all is
-	 * fine. This is however not always the case - buffers may be allocated
-	 * using kmalloc() - so the usb core needs to be told that it must copy
-	 * data into our local memory if the buffers happen to be placed in
-	 * regular memory. The HCD_LOCAL_MEM flag does just that.
-	 */
-
-	retval = dma_declare_coherent_memory(dev, mem->start,
-					 mem->start - mem->parent->start,
-					 resource_size(mem));
-	if (retval) {
-		dev_err(dev, "cannot declare coherent memory\n");
-		goto err1;
-	}
-
 	/* allocate, reserve and remap resources for registers */
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (res == NULL) {
 		dev_err(dev, "no resource definition for registers\n");
 		retval = -ENOENT;
-		goto err2;
+		goto err1;
 	}
 
 	hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
 	if (!hcd) {
 		retval = -ENOMEM;
-		goto err2;
+		goto err1;
 	}
 
 	hcd->rsrc_start = res->start;
@@ -164,6 +142,24 @@ static int ohci_hcd_sm501_drv_probe(struct platform_device *pdev)
 
 	ohci_hcd_init(hcd_to_ohci(hcd));
 
+	/* The sm501 chip is equipped with local memory that may be used
+	 * by on-chip devices such as the video controller and the usb host.
+	 * This driver uses genalloc so that usb allocations with
+	 * gen_pool_dma_alloc() allocate from this local memory. The dma_handle
+	 * returned by gen_pool_dma_alloc() will be an offset starting from 0
+	 * for the first local memory byte.
+	 *
+	 * So as long as data is allocated using gen_pool_dma_alloc() all is
+	 * fine. This is however not always the case - buffers may be allocated
+	 * using kmalloc() - so the usb core needs to be told that it must copy
+	 * data into our local memory if the buffers happen to be placed in
+	 * regular memory. The HCD_LOCAL_MEM flag does just that.
+	 */
+
+	if (usb_hcd_setup_local_mem(hcd, mem->start,
+				    mem->start - mem->parent->start,
+				    resource_size(mem)) < 0)
+		goto err5;
 	retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
 	if (retval)
 		goto err5;
@@ -181,8 +177,6 @@ static int ohci_hcd_sm501_drv_probe(struct platform_device *pdev)
 	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
 err3:
 	usb_put_hcd(hcd);
-err2:
-	dma_release_declared_memory(dev);
 err1:
 	release_mem_region(mem->start, resource_size(mem));
 err0:
@@ -197,7 +191,6 @@ static int ohci_hcd_sm501_drv_remove(struct platform_device *pdev)
 	usb_remove_hcd(hcd);
 	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
 	usb_put_hcd(hcd);
-	dma_release_declared_memory(&pdev->dev);
 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 	if (mem)
 		release_mem_region(mem->start, resource_size(mem));
-- 
2.17.1