diff options
| author | Jiri Slaby (SUSE) <jirislaby@kernel.org> | 2024-04-19 10:09:31 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-04-20 07:58:42 +0200 |
| commit | f70f95b485d78838ad28dbec804b986d11ad7bb0 (patch) | |
| tree | 982e6d07ec1284c867dc079e0a11cd0f014b8bfe /drivers/tty/serial/msm_serial.c | |
| parent | c6795fbffc4547b40933ec368200bd4926a41b44 (diff) | |
serial: msm: check dma_map_sg() return value properly
The -next commit f8fef2fa419f (tty: msm_serial: use
dmaengine_prep_slave_sg()), switched to using dma_map_sg(). But the
return value of dma_map_sg() is special: it returns number of elements
mapped. And not a standard error value.
The commit also forgot to reset dma->tx_sg in case of this failure.
Fix both these mistakes.
Thanks to Marek who helped debugging this.
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20240419080931.30949-1-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial/msm_serial.c')
| -rw-r--r-- | drivers/tty/serial/msm_serial.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c index ae7a8e3cf467..0a9c5219df88 100644 --- a/drivers/tty/serial/msm_serial.c +++ b/drivers/tty/serial/msm_serial.c @@ -499,15 +499,18 @@ static int msm_handle_tx_dma(struct msm_port *msm_port, unsigned int count) struct uart_port *port = &msm_port->uart; struct tty_port *tport = &port->state->port; struct msm_dma *dma = &msm_port->tx_dma; + unsigned int mapped; int ret; u32 val; sg_init_table(&dma->tx_sg, 1); kfifo_dma_out_prepare(&tport->xmit_fifo, &dma->tx_sg, 1, count); - ret = dma_map_sg(port->dev, &dma->tx_sg, 1, dma->dir); - if (ret) - return ret; + mapped = dma_map_sg(port->dev, &dma->tx_sg, 1, dma->dir); + if (!mapped) { + ret = -EIO; + goto zero_sg; + } dma->desc = dmaengine_prep_slave_sg(dma->chan, &dma->tx_sg, 1, DMA_MEM_TO_DEV, @@ -548,6 +551,7 @@ static int msm_handle_tx_dma(struct msm_port *msm_port, unsigned int count) return 0; unmap: dma_unmap_sg(port->dev, &dma->tx_sg, 1, dma->dir); +zero_sg: sg_init_table(&dma->tx_sg, 1); return ret; } |