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 | 60 +++++++++++++++++++---------------- 1 file changed, 33 insertions(+), 27 deletions(-) diff --git a/drivers/usb/host/ohci-sm501.c b/drivers/usb/host/ohci-sm501.c index c26228c25f99..8b829eca04ab 100644 --- a/drivers/usb/host/ohci-sm501.c +++ b/drivers/usb/host/ohci-sm501.c @@ -16,6 +16,7 @@ #include <linux/jiffies.h> #include <linux/platform_device.h> #include <linux/dma-mapping.h> +#include <linux/genalloc.h> #include <linux/sm501.h> #include <linux/sm501-regs.h> @@ -110,40 +111,18 @@ 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 +143,36 @@ 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. + */ + + hcd->localmem_pool = devm_gen_pool_create(dev, PAGE_SHIFT, + dev_to_node(dev), + "ohci-sm501"); + if (IS_ERR(hcd->localmem_pool)) { + retval = PTR_ERR(hcd->localmem_pool); + goto err5; + } + retval = gen_pool_add_virt(hcd->localmem_pool, + (unsigned long)mem->start - + mem->parent->start, + mem->start, resource_size(mem), + dev_to_node(dev)); + if (retval < 0) { + dev_err(dev, "failed to add to pool: %d\n", retval); + goto err5; + } retval = usb_add_hcd(hcd, irq, IRQF_SHARED); if (retval) goto err5; @@ -181,8 +190,6 @@ 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 +204,6 @@ 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