From b0310c2f09bbe8aebefb97ed67949a3a7092aca6 Mon Sep 17 00:00:00 2001
From: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Date: Wed, 29 May 2019 13:28:40 +0300
Subject: USB: use genalloc for USB HCs with local memory
For HCs that have local memory, replace the current DMA API usage with
a genalloc generic allocator to manage the mappings for these devices.
To help users, introduce a new HCD API, usb_hcd_setup_local_mem() that
will setup up the genalloc backing up the device local memory. It will
be used in subsequent patches. This is in preparation for dropping
the existing "coherent" dma mem declaration APIs. The current
implementation was relying on a short circuit in the DMA API that in
the end, was acting as an allocator for these type of devices.
Signed-off-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Tested-by: Fredrik Noring <noring@nocrew.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/usb/core/buffer.c | 9 +++++++++
1 file changed, 9 insertions(+)
(limited to 'drivers/usb/core/buffer.c')
diff --git a/drivers/usb/core/buffer.c b/drivers/usb/core/buffer.c
index f641342cdec0..d2064ad7ad14 100644
--- a/drivers/usb/core/buffer.c
+++ b/drivers/usb/core/buffer.c
@@ -16,6 +16,7 @@
#include <linux/io.h>
#include <linux/dma-mapping.h>
#include <linux/dmapool.h>
+#include <linux/genalloc.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
@@ -124,6 +125,9 @@ void *hcd_buffer_alloc(
if (size == 0)
return NULL;
+ if (hcd->localmem_pool)
+ return gen_pool_dma_alloc(hcd->localmem_pool, size, dma);
+
/* some USB hosts just use PIO */
if (!IS_ENABLED(CONFIG_HAS_DMA) ||
(!is_device_dma_capable(bus->sysdev) &&
@@ -152,6 +156,11 @@ void hcd_buffer_free(
if (!addr)
return;
+ if (hcd->localmem_pool) {
+ gen_pool_free(hcd->localmem_pool, (unsigned long)addr, size);
+ return;
+ }
+
if (!IS_ENABLED(CONFIG_HAS_DMA) ||
(!is_device_dma_capable(bus->sysdev) &&
!(hcd->driver->flags & HCD_LOCAL_MEM))) {
--
cgit v1.2.3-70-g09d2