diff options
| author | Jon Hunter <jonathanh@nvidia.com> | 2015-05-05 16:17:59 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-05-10 19:12:19 +0200 |
| commit | ad909b3f8b162a61ce9e32726dadb380e51f8949 (patch) | |
| tree | 4451c62fde6d0ca954d6d329fbe63468fc55abeb | |
| parent | serial: tegra: Correct shutdown of UARTs (diff) | |
| download | linux-ad909b3f8b162a61ce9e32726dadb380e51f8949.tar.xz linux-ad909b3f8b162a61ce9e32726dadb380e51f8949.zip | |
serial: tegra: Correct error handling on DMA setup
Function tegra_uart_dma_channel_allocate() does not check that
dma_map_single() mapped the DMA buffer correctly. Add a check for this
and appropriate error handling.
Furthermore, if dmaengine_slave_config() (called by
tegra_uart_dma_channel_allocate()) fails, then memory allocated/mapped
is not freed/unmapped. Therefore, call tegra_uart_dma_channel_free()
instead of just dma_release_channel() if dmaengine_slave_config() fails.
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/tty/serial/serial-tegra.c | 51 |
1 files changed, 28 insertions, 23 deletions
diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c index 96378da9aefc..3b63f103f0c9 100644 --- a/drivers/tty/serial/serial-tegra.c +++ b/drivers/tty/serial/serial-tegra.c @@ -949,6 +949,28 @@ static int tegra_uart_hw_init(struct tegra_uart_port *tup) return 0; } +static void tegra_uart_dma_channel_free(struct tegra_uart_port *tup, + bool dma_to_memory) +{ + if (dma_to_memory) { + dmaengine_terminate_all(tup->rx_dma_chan); + dma_release_channel(tup->rx_dma_chan); + dma_free_coherent(tup->uport.dev, TEGRA_UART_RX_DMA_BUFFER_SIZE, + tup->rx_dma_buf_virt, tup->rx_dma_buf_phys); + tup->rx_dma_chan = NULL; + tup->rx_dma_buf_phys = 0; + tup->rx_dma_buf_virt = NULL; + } else { + dmaengine_terminate_all(tup->tx_dma_chan); + dma_release_channel(tup->tx_dma_chan); + dma_unmap_single(tup->uport.dev, tup->tx_dma_buf_phys, + UART_XMIT_SIZE, DMA_TO_DEVICE); + tup->tx_dma_chan = NULL; + tup->tx_dma_buf_phys = 0; + tup->tx_dma_buf_virt = NULL; + } +} + static int tegra_uart_dma_channel_allocate(struct tegra_uart_port *tup, bool dma_to_memory) { @@ -981,6 +1003,11 @@ static int tegra_uart_dma_channel_allocate(struct tegra_uart_port *tup, dma_phys = dma_map_single(tup->uport.dev, tup->uport.state->xmit.buf, UART_XMIT_SIZE, DMA_TO_DEVICE); + if (dma_mapping_error(tup->uport.dev, dma_phys)) { + dev_err(tup->uport.dev, "dma_map_single tx failed\n"); + dma_release_channel(dma_chan); + return -ENOMEM; + } dma_buf = tup->uport.state->xmit.buf; } @@ -1013,32 +1040,10 @@ static int tegra_uart_dma_channel_allocate(struct tegra_uart_port *tup, return 0; scrub: - dma_release_channel(dma_chan); + tegra_uart_dma_channel_free(tup, dma_to_memory); return ret; } -static void tegra_uart_dma_channel_free(struct tegra_uart_port *tup, - bool dma_to_memory) -{ - if (dma_to_memory) { - dmaengine_terminate_all(tup->rx_dma_chan); - dma_release_channel(tup->rx_dma_chan); - dma_free_coherent(tup->uport.dev, TEGRA_UART_RX_DMA_BUFFER_SIZE, - tup->rx_dma_buf_virt, tup->rx_dma_buf_phys); - tup->rx_dma_chan = NULL; - tup->rx_dma_buf_phys = 0; - tup->rx_dma_buf_virt = NULL; - } else { - dmaengine_terminate_all(tup->tx_dma_chan); - dma_release_channel(tup->tx_dma_chan); - dma_unmap_single(tup->uport.dev, tup->tx_dma_buf_phys, - UART_XMIT_SIZE, DMA_TO_DEVICE); - tup->tx_dma_chan = NULL; - tup->tx_dma_buf_phys = 0; - tup->tx_dma_buf_virt = NULL; - } -} - static int tegra_uart_startup(struct uart_port *u) { struct tegra_uart_port *tup = to_tegra_uport(u); |