| Message ID | 20170630120446.13994-8-romain.perier@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Jun 30, 2017 at 02:04:46PM +0200, Romain Perier wrote: > From: Nandor Han <nandor.han@ge.com> > > In some cases, It looks that interrupts can happen after the dma was s/It/it/ > disabled and port was not yet shutdown. This will result in interrupts > handled by imx_rxint. > > This commits updates the shutdown function to ensure that underlying > components are disabled in the right order. This disables RX and TX > blocks, then it disabled interrupts. In case DMA is enabled, it disables > DMA and free corresponding resources. It disables UART port and stop > clocks. > > Signed-off-by: Nandor Han <nandor.han@ge.com> > Signed-off-by: Romain Perier <romain.perier@collabora.com> > --- > drivers/tty/serial/imx.c | 38 +++++++++++++++++++------------------- > 1 file changed, 19 insertions(+), 19 deletions(-) > > diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c > index d5b6e09..7dc6f0c 100644 > --- a/drivers/tty/serial/imx.c > +++ b/drivers/tty/serial/imx.c > @@ -1404,44 +1404,44 @@ static void imx_shutdown(struct uart_port *port) > unsigned long temp; > unsigned long flags; > > - if (sport->dma_is_enabled) { > - sport->dma_is_rxing = 0; > - sport->dma_is_txing = 0; > - dmaengine_terminate_sync(sport->dma_chan_tx); > - dmaengine_terminate_sync(sport->dma_chan_rx); > - > + if (!sport->port.suspended) { > spin_lock_irqsave(&sport->port.lock, flags); > imx_stop_tx(port); > imx_stop_rx(port); > - imx_disable_dma(sport); > spin_unlock_irqrestore(&sport->port.lock, flags); > - imx_uart_dma_exit(sport); > } > > - mctrl_gpio_disable_ms(sport->gpios); > + if (sport->dma_is_inited) { > + if (sport->dma_is_enabled) { > + spin_lock_irqsave(&sport->port.lock, flags); > + imx_disable_dma(sport); > + spin_unlock_irqrestore(&sport->port.lock, flags); > + } > + imx_uart_dma_exit(sport); > + } > > spin_lock_irqsave(&sport->port.lock, flags); > temp = readl(sport->port.membase + UCR2); > - temp &= ~(UCR2_TXEN); > + temp &= ~(UCR2_TXEN | UCR2_RXEN); > writel(temp, sport->port.membase + UCR2); > + temp = readl(sport->port.membase + UCR4); > + temp &= ~UCR4_OREN; > + writel(temp, sport->port.membase + UCR4); > spin_unlock_irqrestore(&sport->port.lock, flags); The function already had two critical blocks protected by spin_lock_irqsave on sport->port.lock. With your patch there are three. Is it possible to grab the lock only once? > > - /* > - * Stop our timer. > - */ > - del_timer_sync(&sport->timer); > + mctrl_gpio_disable_ms(sport->gpios); > > - /* > - * Disable all interrupts, port and break condition. > - */ > + /* Stop our timer. */ Updating the comment style in such a commit makes the diff unnecessarily hard to read. > + del_timer_sync(&sport->timer); > > + /* Disable port. */ > spin_lock_irqsave(&sport->port.lock, flags); > temp = readl(sport->port.membase + UCR1); > - temp &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN); > - > + temp &= ~UCR1_UARTEN; > writel(temp, sport->port.membase + UCR1); > spin_unlock_irqrestore(&sport->port.lock, flags); > > + /* Disable clocks. */ > clk_disable_unprepare(sport->clk_per); > clk_disable_unprepare(sport->clk_ipg); > } > -- > 1.8.3.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-serial" 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/imx.c b/drivers/tty/serial/imx.c index d5b6e09..7dc6f0c 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -1404,44 +1404,44 @@ static void imx_shutdown(struct uart_port *port) unsigned long temp; unsigned long flags; - if (sport->dma_is_enabled) { - sport->dma_is_rxing = 0; - sport->dma_is_txing = 0; - dmaengine_terminate_sync(sport->dma_chan_tx); - dmaengine_terminate_sync(sport->dma_chan_rx); - + if (!sport->port.suspended) { spin_lock_irqsave(&sport->port.lock, flags); imx_stop_tx(port); imx_stop_rx(port); - imx_disable_dma(sport); spin_unlock_irqrestore(&sport->port.lock, flags); - imx_uart_dma_exit(sport); } - mctrl_gpio_disable_ms(sport->gpios); + if (sport->dma_is_inited) { + if (sport->dma_is_enabled) { + spin_lock_irqsave(&sport->port.lock, flags); + imx_disable_dma(sport); + spin_unlock_irqrestore(&sport->port.lock, flags); + } + imx_uart_dma_exit(sport); + } spin_lock_irqsave(&sport->port.lock, flags); temp = readl(sport->port.membase + UCR2); - temp &= ~(UCR2_TXEN); + temp &= ~(UCR2_TXEN | UCR2_RXEN); writel(temp, sport->port.membase + UCR2); + temp = readl(sport->port.membase + UCR4); + temp &= ~UCR4_OREN; + writel(temp, sport->port.membase + UCR4); spin_unlock_irqrestore(&sport->port.lock, flags); - /* - * Stop our timer. - */ - del_timer_sync(&sport->timer); + mctrl_gpio_disable_ms(sport->gpios); - /* - * Disable all interrupts, port and break condition. - */ + /* Stop our timer. */ + del_timer_sync(&sport->timer); + /* Disable port. */ spin_lock_irqsave(&sport->port.lock, flags); temp = readl(sport->port.membase + UCR1); - temp &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN); - + temp &= ~UCR1_UARTEN; writel(temp, sport->port.membase + UCR1); spin_unlock_irqrestore(&sport->port.lock, flags); + /* Disable clocks. */ clk_disable_unprepare(sport->clk_per); clk_disable_unprepare(sport->clk_ipg); }