diff options
Diffstat (limited to 'drivers/tty/serial/8250/8250_omap.c')
| -rw-r--r-- | drivers/tty/serial/8250/8250_omap.c | 193 |
1 files changed, 120 insertions, 73 deletions
diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c index 9289999cb7c6..d75a66c72750 100644 --- a/drivers/tty/serial/8250/8250_omap.c +++ b/drivers/tty/serial/8250/8250_omap.c @@ -22,6 +22,7 @@ #include <linux/pm_runtime.h> #include <linux/console.h> #include <linux/pm_qos.h> +#include <linux/pm_wakeirq.h> #include <linux/dma-mapping.h> #include "8250.h" @@ -98,6 +99,7 @@ struct omap8250_priv { struct pm_qos_request pm_qos_request; struct work_struct qos_work; struct uart_8250_dma omap8250_dma; + spinlock_t rx_dma_lock; }; static u32 uart_read(struct uart_8250_port *up, u32 reg) @@ -551,39 +553,71 @@ static void omap8250_uart_qos_work(struct work_struct *work) pm_qos_update_request(&priv->pm_qos_request, priv->latency); } -static irqreturn_t omap_wake_irq(int irq, void *dev_id) +#ifdef CONFIG_SERIAL_8250_DMA +static int omap_8250_dma_handle_irq(struct uart_port *port); +#endif + +static irqreturn_t omap8250_irq(int irq, void *dev_id) { struct uart_port *port = dev_id; + struct uart_8250_port *up = up_to_u8250p(port); + unsigned int iir; int ret; - ret = port->handle_irq(port); - if (ret) - return IRQ_HANDLED; - return IRQ_NONE; +#ifdef CONFIG_SERIAL_8250_DMA + if (up->dma) { + ret = omap_8250_dma_handle_irq(port); + return IRQ_RETVAL(ret); + } +#endif + + serial8250_rpm_get(up); + iir = serial_port_in(port, UART_IIR); + ret = serial8250_handle_irq(port, iir); + serial8250_rpm_put(up); + + return IRQ_RETVAL(ret); } static int omap_8250_startup(struct uart_port *port) { - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); + struct uart_8250_port *up = up_to_u8250p(port); struct omap8250_priv *priv = port->private_data; - int ret; if (priv->wakeirq) { - ret = request_irq(priv->wakeirq, omap_wake_irq, - port->irqflags, "uart wakeup irq", port); + ret = dev_pm_set_dedicated_wake_irq(port->dev, priv->wakeirq); if (ret) return ret; - disable_irq(priv->wakeirq); } pm_runtime_get_sync(port->dev); - ret = serial8250_do_startup(port); - if (ret) + up->mcr = 0; + serial_out(up, UART_FCR, UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); + + serial_out(up, UART_LCR, UART_LCR_WLEN8); + + up->lsr_saved_flags = 0; + up->msr_saved_flags = 0; + + if (up->dma) { + ret = serial8250_request_dma(up); + if (ret) { + dev_warn_ratelimited(port->dev, + "failed to request DMA\n"); + up->dma = NULL; + } + } + + ret = request_irq(port->irq, omap8250_irq, IRQF_SHARED, + dev_name(port->dev), port); + if (ret < 0) goto err; + up->ier = UART_IER_RLSI | UART_IER_RDI; + serial_out(up, UART_IER, up->ier); + #ifdef CONFIG_PM up->capabilities |= UART_CAP_RPM; #endif @@ -603,15 +637,13 @@ static int omap_8250_startup(struct uart_port *port) err: pm_runtime_mark_last_busy(port->dev); pm_runtime_put_autosuspend(port->dev); - if (priv->wakeirq) - free_irq(priv->wakeirq, port); + dev_pm_clear_wake_irq(port->dev); return ret; } static void omap_8250_shutdown(struct uart_port *port) { - struct uart_8250_port *up = - container_of(port, struct uart_8250_port, port); + struct uart_8250_port *up = up_to_u8250p(port); struct omap8250_priv *priv = port->private_data; flush_work(&priv->qos_work); @@ -621,13 +653,24 @@ static void omap_8250_shutdown(struct uart_port *port) pm_runtime_get_sync(port->dev); serial_out(up, UART_OMAP_WER, 0); - serial8250_do_shutdown(port); + + up->ier = 0; + serial_out(up, UART_IER, 0); + + if (up->dma) + serial8250_release_dma(up); + + /* + * Disable break condition and FIFOs + */ + if (up->lcr & UART_LCR_SBC) + serial_out(up, UART_LCR, up->lcr & ~UART_LCR_SBC); + serial_out(up, UART_FCR, UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); pm_runtime_mark_last_busy(port->dev); pm_runtime_put_autosuspend(port->dev); - - if (priv->wakeirq) - free_irq(priv->wakeirq, port); + free_irq(port->irq, port); + dev_pm_clear_wake_irq(port->dev); } static void omap_8250_throttle(struct uart_port *port) @@ -669,14 +712,21 @@ static int omap_8250_rx_dma(struct uart_8250_port *p, unsigned int iir); static void __dma_rx_do_complete(struct uart_8250_port *p, bool error) { + struct omap8250_priv *priv = p->port.private_data; struct uart_8250_dma *dma = p->dma; struct tty_port *tty_port = &p->port.state->port; struct dma_tx_state state; int count; + unsigned long flags; dma_sync_single_for_cpu(dma->rxchan->device->dev, dma->rx_addr, dma->rx_size, DMA_FROM_DEVICE); + spin_lock_irqsave(&priv->rx_dma_lock, flags); + + if (!dma->rx_running) + goto unlock; + dma->rx_running = 0; dmaengine_tx_status(dma->rxchan, dma->rx_cookie, &state); dmaengine_terminate_all(dma->rxchan); @@ -685,6 +735,9 @@ static void __dma_rx_do_complete(struct uart_8250_port *p, bool error) tty_insert_flip_string(tty_port, dma->rx_buf, count); p->port.icount.rx += count; +unlock: + spin_unlock_irqrestore(&priv->rx_dma_lock, flags); + if (!error) omap_8250_rx_dma(p, 0); @@ -696,28 +749,45 @@ static void __dma_rx_complete(void *param) __dma_rx_do_complete(param, false); } +static void omap_8250_rx_dma_flush(struct uart_8250_port *p) +{ + struct omap8250_priv *priv = p->port.private_data; + struct uart_8250_dma *dma = p->dma; + unsigned long flags; + + spin_lock_irqsave(&priv->rx_dma_lock, flags); + + if (!dma->rx_running) { + spin_unlock_irqrestore(&priv->rx_dma_lock, flags); + return; + } + + dmaengine_pause(dma->rxchan); + + spin_unlock_irqrestore(&priv->rx_dma_lock, flags); + + __dma_rx_do_complete(p, true); +} + static int omap_8250_rx_dma(struct uart_8250_port *p, unsigned int iir) { + struct omap8250_priv *priv = p->port.private_data; struct uart_8250_dma *dma = p->dma; + int err = 0; struct dma_async_tx_descriptor *desc; + unsigned long flags; switch (iir & 0x3f) { case UART_IIR_RLSI: /* 8250_core handles errors and break interrupts */ - if (dma->rx_running) { - dmaengine_pause(dma->rxchan); - __dma_rx_do_complete(p, true); - } + omap_8250_rx_dma_flush(p); return -EIO; case UART_IIR_RX_TIMEOUT: /* * If RCVR FIFO trigger level was not reached, complete the * transfer and let 8250_core copy the remaining data. */ - if (dma->rx_running) { - dmaengine_pause(dma->rxchan); - __dma_rx_do_complete(p, true); - } + omap_8250_rx_dma_flush(p); return -ETIMEDOUT; case UART_IIR_RDI: /* @@ -729,24 +799,25 @@ static int omap_8250_rx_dma(struct uart_8250_port *p, unsigned int iir) * the DMA won't do anything soon so we have to cancel the DMA * transfer and purge the FIFO manually. */ - if (dma->rx_running) { - dmaengine_pause(dma->rxchan); - __dma_rx_do_complete(p, true); - } + omap_8250_rx_dma_flush(p); return -ETIMEDOUT; default: break; } + spin_lock_irqsave(&priv->rx_dma_lock, flags); + if (dma->rx_running) - return 0; + goto out; desc = dmaengine_prep_slave_single(dma->rxchan, dma->rx_addr, dma->rx_size, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); - if (!desc) - return -EBUSY; + if (!desc) { + err = -EBUSY; + goto out; + } dma->rx_running = 1; desc->callback = __dma_rx_complete; @@ -758,7 +829,9 @@ static int omap_8250_rx_dma(struct uart_8250_port *p, unsigned int iir) dma->rx_size, DMA_FROM_DEVICE); dma_async_issue_pending(dma->rxchan); - return 0; +out: + spin_unlock_irqrestore(&priv->rx_dma_lock, flags); + return err; } static int omap_8250_tx_dma(struct uart_8250_port *p); @@ -974,6 +1047,13 @@ static inline int omap_8250_rx_dma(struct uart_8250_port *p, unsigned int iir) } #endif +static int omap8250_no_handle_irq(struct uart_port *port) +{ + /* IRQ has not been requested but handling irq? */ + WARN_ONCE(1, "Unexpected irq handling before port startup\n"); + return 0; +} + static int omap8250_probe(struct platform_device *pdev) { struct resource *regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); @@ -1065,6 +1145,8 @@ static int omap8250_probe(struct platform_device *pdev) priv->latency); INIT_WORK(&priv->qos_work, omap8250_uart_qos_work); + spin_lock_init(&priv->rx_dma_lock); + device_init_wakeup(&pdev->dev, true); pm_runtime_use_autosuspend(&pdev->dev); pm_runtime_set_autosuspend_delay(&pdev->dev, -1); @@ -1075,6 +1157,7 @@ static int omap8250_probe(struct platform_device *pdev) pm_runtime_get_sync(&pdev->dev); omap_serial_fill_features_erratas(&up, priv); + up.port.handle_irq = omap8250_no_handle_irq; #ifdef CONFIG_SERIAL_8250_DMA if (pdev->dev.of_node) { /* @@ -1088,7 +1171,6 @@ static int omap8250_probe(struct platform_device *pdev) ret = of_property_count_strings(pdev->dev.of_node, "dma-names"); if (ret == 2) { up.dma = &priv->omap8250_dma; - up.port.handle_irq = omap_8250_dma_handle_irq; priv->omap8250_dma.fn = the_no_dma_filter_fn; priv->omap8250_dma.tx_dma = omap_8250_tx_dma; priv->omap8250_dma.rx_dma = omap_8250_rx_dma; @@ -1129,31 +1211,6 @@ static int omap8250_remove(struct platform_device *pdev) return 0; } -#ifdef CONFIG_PM - -static inline void omap8250_enable_wakeirq(struct omap8250_priv *priv, - bool enable) -{ - if (!priv->wakeirq) - return; - - if (enable) - enable_irq(priv->wakeirq); - else - disable_irq_nosync(priv->wakeirq); -} - -static void omap8250_enable_wakeup(struct omap8250_priv *priv, - bool enable) -{ - if (enable == priv->wakeups_enabled) - return; - - omap8250_enable_wakeirq(priv, enable); - priv->wakeups_enabled = enable; -} -#endif - #ifdef CONFIG_PM_SLEEP static int omap8250_prepare(struct device *dev) { @@ -1180,11 +1237,6 @@ static int omap8250_suspend(struct device *dev) serial8250_suspend_port(priv->line); flush_work(&priv->qos_work); - - if (device_may_wakeup(dev)) - omap8250_enable_wakeup(priv, true); - else - omap8250_enable_wakeup(priv, false); return 0; } @@ -1192,9 +1244,6 @@ static int omap8250_resume(struct device *dev) { struct omap8250_priv *priv = dev_get_drvdata(dev); - if (device_may_wakeup(dev)) - omap8250_enable_wakeup(priv, false); - serial8250_resume_port(priv->line); return 0; } @@ -1236,7 +1285,6 @@ static int omap8250_runtime_suspend(struct device *dev) return -EBUSY; } - omap8250_enable_wakeup(priv, true); if (up->dma) omap_8250_rx_dma(up, UART_IIR_RX_TIMEOUT); @@ -1257,7 +1305,6 @@ static int omap8250_runtime_resume(struct device *dev) return 0; up = serial8250_get_port(priv->line); - omap8250_enable_wakeup(priv, false); loss_cntx = omap8250_lost_context(up); if (loss_cntx) |
