| Message ID | 1491200468-28463-1-git-send-email-m.szyprowski@samsung.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
On Mon, Apr 3, 2017 at 12:20 AM, Marek Szyprowski <m.szyprowski@samsung.com> wrote: > Driver should provide its own struct device for all DMA-mapping calls instead > of extracting device pointer from DMA engine channel. Although this is harmless > from the driver operation perspective on ARM architecture, it is always good > to use the DMA mapping API in a proper way. This patch fixes following DMA API > debug warning: > > WARNING: CPU: 0 PID: 0 at lib/dma-debug.c:1241 check_sync+0x520/0x9f4 > samsung-uart 12c20000.serial: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x000000006df0f580] [size=64 bytes] > Modules linked in: > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.11.0-rc1-00137-g07ca963 #51 > Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) > [<c011aaa4>] (unwind_backtrace) from [<c01127c0>] (show_stack+0x20/0x24) > [<c01127c0>] (show_stack) from [<c06ba5d8>] (dump_stack+0x84/0xa0) > [<c06ba5d8>] (dump_stack) from [<c0139528>] (__warn+0x14c/0x180) > [<c0139528>] (__warn) from [<c01395a4>] (warn_slowpath_fmt+0x48/0x50) > [<c01395a4>] (warn_slowpath_fmt) from [<c0729058>] (check_sync+0x520/0x9f4) > [<c0729058>] (check_sync) from [<c072967c>] (debug_dma_sync_single_for_device+0x88/0xc8) > [<c072967c>] (debug_dma_sync_single_for_device) from [<c0803c10>] (s3c24xx_serial_start_tx_dma+0x100/0x2f8) > [<c0803c10>] (s3c24xx_serial_start_tx_dma) from [<c0804338>] (s3c24xx_serial_tx_chars+0x198/0x33c) > > Reported-by: Seung-Woo Kim <sw0312.kim@samsung.com> > Fixes: 62c37eedb74c8 ("serial: samsung: add dma reqest/release functions") > CC: stable@vger.kernel.org # v4.0+ > Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> > Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> > Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org> The change looks good. Reviewed-by: Shuah Khan <shuahkh@osg.samsung.com> -- Shuah > --- > v3: > - extended commit message > > v2: > - fixed commit id in 'fixes' tag, added 'reviewed-by' tag > --- > drivers/tty/serial/samsung.c | 9 ++++----- > 1 file changed, 4 insertions(+), 5 deletions(-) > > diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c > index 7a17aedbf902..9f3759bdb44f 100644 > --- a/drivers/tty/serial/samsung.c > +++ b/drivers/tty/serial/samsung.c > @@ -901,14 +901,13 @@ static int s3c24xx_serial_request_dma(struct s3c24xx_uart_port *p) > return -ENOMEM; > } > > - dma->rx_addr = dma_map_single(dma->rx_chan->device->dev, dma->rx_buf, > + dma->rx_addr = dma_map_single(p->port.dev, dma->rx_buf, > dma->rx_size, DMA_FROM_DEVICE); > > spin_lock_irqsave(&p->port.lock, flags); > > /* TX buffer */ > - dma->tx_addr = dma_map_single(dma->tx_chan->device->dev, > - p->port.state->xmit.buf, > + dma->tx_addr = dma_map_single(p->port.dev, p->port.state->xmit.buf, > UART_XMIT_SIZE, DMA_TO_DEVICE); > > spin_unlock_irqrestore(&p->port.lock, flags); > @@ -922,7 +921,7 @@ static void s3c24xx_serial_release_dma(struct s3c24xx_uart_port *p) > > if (dma->rx_chan) { > dmaengine_terminate_all(dma->rx_chan); > - dma_unmap_single(dma->rx_chan->device->dev, dma->rx_addr, > + dma_unmap_single(p->port.dev, dma->rx_addr, > dma->rx_size, DMA_FROM_DEVICE); > kfree(dma->rx_buf); > dma_release_channel(dma->rx_chan); > @@ -931,7 +930,7 @@ static void s3c24xx_serial_release_dma(struct s3c24xx_uart_port *p) > > if (dma->tx_chan) { > dmaengine_terminate_all(dma->tx_chan); > - dma_unmap_single(dma->tx_chan->device->dev, dma->tx_addr, > + dma_unmap_single(p->port.dev, dma->tx_addr, > UART_XMIT_SIZE, DMA_TO_DEVICE); > dma_release_channel(dma->tx_chan); > dma->tx_chan = NULL; > -- > 1.9.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c index 7a17aedbf902..9f3759bdb44f 100644 --- a/drivers/tty/serial/samsung.c +++ b/drivers/tty/serial/samsung.c @@ -901,14 +901,13 @@ static int s3c24xx_serial_request_dma(struct s3c24xx_uart_port *p) return -ENOMEM; } - dma->rx_addr = dma_map_single(dma->rx_chan->device->dev, dma->rx_buf, + dma->rx_addr = dma_map_single(p->port.dev, dma->rx_buf, dma->rx_size, DMA_FROM_DEVICE); spin_lock_irqsave(&p->port.lock, flags); /* TX buffer */ - dma->tx_addr = dma_map_single(dma->tx_chan->device->dev, - p->port.state->xmit.buf, + dma->tx_addr = dma_map_single(p->port.dev, p->port.state->xmit.buf, UART_XMIT_SIZE, DMA_TO_DEVICE); spin_unlock_irqrestore(&p->port.lock, flags); @@ -922,7 +921,7 @@ static void s3c24xx_serial_release_dma(struct s3c24xx_uart_port *p) if (dma->rx_chan) { dmaengine_terminate_all(dma->rx_chan); - dma_unmap_single(dma->rx_chan->device->dev, dma->rx_addr, + dma_unmap_single(p->port.dev, dma->rx_addr, dma->rx_size, DMA_FROM_DEVICE); kfree(dma->rx_buf); dma_release_channel(dma->rx_chan); @@ -931,7 +930,7 @@ static void s3c24xx_serial_release_dma(struct s3c24xx_uart_port *p) if (dma->tx_chan) { dmaengine_terminate_all(dma->tx_chan); - dma_unmap_single(dma->tx_chan->device->dev, dma->tx_addr, + dma_unmap_single(p->port.dev, dma->tx_addr, UART_XMIT_SIZE, DMA_TO_DEVICE); dma_release_channel(dma->tx_chan); dma->tx_chan = NULL;
Driver should provide its own struct device for all DMA-mapping calls instead of extracting device pointer from DMA engine channel. Although this is harmless from the driver operation perspective on ARM architecture, it is always good to use the DMA mapping API in a proper way. This patch fixes following DMA API debug warning: WARNING: CPU: 0 PID: 0 at lib/dma-debug.c:1241 check_sync+0x520/0x9f4 samsung-uart 12c20000.serial: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x000000006df0f580] [size=64 bytes] Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.11.0-rc1-00137-g07ca963 #51 Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [<c011aaa4>] (unwind_backtrace) from [<c01127c0>] (show_stack+0x20/0x24) [<c01127c0>] (show_stack) from [<c06ba5d8>] (dump_stack+0x84/0xa0) [<c06ba5d8>] (dump_stack) from [<c0139528>] (__warn+0x14c/0x180) [<c0139528>] (__warn) from [<c01395a4>] (warn_slowpath_fmt+0x48/0x50) [<c01395a4>] (warn_slowpath_fmt) from [<c0729058>] (check_sync+0x520/0x9f4) [<c0729058>] (check_sync) from [<c072967c>] (debug_dma_sync_single_for_device+0x88/0xc8) [<c072967c>] (debug_dma_sync_single_for_device) from [<c0803c10>] (s3c24xx_serial_start_tx_dma+0x100/0x2f8) [<c0803c10>] (s3c24xx_serial_start_tx_dma) from [<c0804338>] (s3c24xx_serial_tx_chars+0x198/0x33c) Reported-by: Seung-Woo Kim <sw0312.kim@samsung.com> Fixes: 62c37eedb74c8 ("serial: samsung: add dma reqest/release functions") CC: stable@vger.kernel.org # v4.0+ Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org> --- v3: - extended commit message v2: - fixed commit id in 'fixes' tag, added 'reviewed-by' tag --- drivers/tty/serial/samsung.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-)