diff options
Diffstat (limited to 'drivers/tty/serial/imx.c')
| -rw-r--r-- | drivers/tty/serial/imx.c | 183 |
1 files changed, 146 insertions, 37 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 54fdc7866..d0388a071 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -216,6 +216,8 @@ struct imx_port { unsigned int tx_bytes; unsigned int dma_tx_nents; wait_queue_head_t dma_wait; + unsigned int saved_reg[10]; + bool context_saved; }; struct imx_port_ucrs { @@ -700,7 +702,8 @@ static irqreturn_t imx_rxint(int irq, void *dev_id) if (sport->port.ignore_status_mask & URXD_DUMMY_READ) goto out; - tty_insert_flip_char(port, rx, flg); + if (tty_insert_flip_char(port, rx, flg) == 0) + sport->port.icount.buf_overrun++; } out: @@ -766,7 +769,6 @@ static irqreturn_t imx_int(int irq, void *dev_id) writel(USR1_AWAKE, sport->port.membase + USR1); if (sts2 & USR2_ORE) { - dev_err(sport->port.dev, "Rx FIFO overrun\n"); sport->port.icount.overrun++; writel(USR2_ORE, sport->port.membase + USR2); } @@ -921,8 +923,13 @@ static void dma_rx_callback(void *data) dev_dbg(sport->port.dev, "We get %d bytes.\n", count); if (count) { - if (!(sport->port.ignore_status_mask & URXD_DUMMY_READ)) - tty_insert_flip_string(port, sport->rx_buf, count); + if (!(sport->port.ignore_status_mask & URXD_DUMMY_READ)) { + int bytes = tty_insert_flip_string(port, sport->rx_buf, + count); + + if (bytes != count) + sport->port.icount.buf_overrun++; + } tty_flip_buffer_push(port); start_rx_dma(sport); @@ -1810,36 +1817,6 @@ static struct uart_driver imx_reg = { .cons = IMX_CONSOLE, }; -static int serial_imx_suspend(struct platform_device *dev, pm_message_t state) -{ - struct imx_port *sport = platform_get_drvdata(dev); - unsigned int val; - - /* enable wakeup from i.MX UART */ - val = readl(sport->port.membase + UCR3); - val |= UCR3_AWAKEN; - writel(val, sport->port.membase + UCR3); - - uart_suspend_port(&imx_reg, &sport->port); - - return 0; -} - -static int serial_imx_resume(struct platform_device *dev) -{ - struct imx_port *sport = platform_get_drvdata(dev); - unsigned int val; - - /* disable wakeup from i.MX UART */ - val = readl(sport->port.membase + UCR3); - val &= ~UCR3_AWAKEN; - writel(val, sport->port.membase + UCR3); - - uart_resume_port(&imx_reg, &sport->port); - - return 0; -} - #ifdef CONFIG_OF /* * This function returns 1 iff pdev isn't a device instatiated by dt, 0 iff it @@ -1901,7 +1878,7 @@ static int serial_imx_probe(struct platform_device *pdev) { struct imx_port *sport; void __iomem *base; - int ret = 0; + int ret = 0, reg; struct resource *res; int txirq, rxirq, rtsirq; @@ -1956,6 +1933,19 @@ static int serial_imx_probe(struct platform_device *pdev) sport->port.uartclk = clk_get_rate(sport->clk_per); + /* For register access, we only need to enable the ipg clock. */ + ret = clk_prepare_enable(sport->clk_ipg); + if (ret) + return ret; + + /* Disable interrupts before requesting them */ + reg = readl_relaxed(sport->port.membase + UCR1); + reg &= ~(UCR1_ADEN | UCR1_TRDYEN | UCR1_IDEN | UCR1_RRDYEN | + UCR1_TXMPTYEN | UCR1_RTSDEN); + writel_relaxed(reg, sport->port.membase + UCR1); + + clk_disable_unprepare(sport->clk_ipg); + /* * Allocate the IRQ(s) i.MX1 has three interrupts whereas later * chips only have one interrupt. @@ -1991,16 +1981,135 @@ static int serial_imx_remove(struct platform_device *pdev) return uart_remove_one_port(&imx_reg, &sport->port); } +static void serial_imx_restore_context(struct imx_port *sport) +{ + if (!sport->context_saved) + return; + + writel(sport->saved_reg[4], sport->port.membase + UFCR); + writel(sport->saved_reg[5], sport->port.membase + UESC); + writel(sport->saved_reg[6], sport->port.membase + UTIM); + writel(sport->saved_reg[7], sport->port.membase + UBIR); + writel(sport->saved_reg[8], sport->port.membase + UBMR); + writel(sport->saved_reg[9], sport->port.membase + IMX21_UTS); + writel(sport->saved_reg[0], sport->port.membase + UCR1); + writel(sport->saved_reg[1] | UCR2_SRST, sport->port.membase + UCR2); + writel(sport->saved_reg[2], sport->port.membase + UCR3); + writel(sport->saved_reg[3], sport->port.membase + UCR4); + sport->context_saved = false; +} + +static void serial_imx_save_context(struct imx_port *sport) +{ + /* Save necessary regs */ + sport->saved_reg[0] = readl(sport->port.membase + UCR1); + sport->saved_reg[1] = readl(sport->port.membase + UCR2); + sport->saved_reg[2] = readl(sport->port.membase + UCR3); + sport->saved_reg[3] = readl(sport->port.membase + UCR4); + sport->saved_reg[4] = readl(sport->port.membase + UFCR); + sport->saved_reg[5] = readl(sport->port.membase + UESC); + sport->saved_reg[6] = readl(sport->port.membase + UTIM); + sport->saved_reg[7] = readl(sport->port.membase + UBIR); + sport->saved_reg[8] = readl(sport->port.membase + UBMR); + sport->saved_reg[9] = readl(sport->port.membase + IMX21_UTS); + sport->context_saved = true; +} + +static void serial_imx_enable_wakeup(struct imx_port *sport, bool on) +{ + unsigned int val; + + val = readl(sport->port.membase + UCR3); + if (on) + val |= UCR3_AWAKEN; + else + val &= ~UCR3_AWAKEN; + writel(val, sport->port.membase + UCR3); + + val = readl(sport->port.membase + UCR1); + if (on) + val |= UCR1_RTSDEN; + else + val &= ~UCR1_RTSDEN; + writel(val, sport->port.membase + UCR1); +} + +static int imx_serial_port_suspend_noirq(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct imx_port *sport = platform_get_drvdata(pdev); + int ret; + + ret = clk_enable(sport->clk_ipg); + if (ret) + return ret; + + serial_imx_save_context(sport); + + clk_disable(sport->clk_ipg); + + return 0; +} + +static int imx_serial_port_resume_noirq(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct imx_port *sport = platform_get_drvdata(pdev); + int ret; + + ret = clk_enable(sport->clk_ipg); + if (ret) + return ret; + + serial_imx_restore_context(sport); + + clk_disable(sport->clk_ipg); + + return 0; +} + +static int imx_serial_port_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct imx_port *sport = platform_get_drvdata(pdev); + + /* enable wakeup from i.MX UART */ + serial_imx_enable_wakeup(sport, true); + + uart_suspend_port(&imx_reg, &sport->port); + + return 0; +} + +static int imx_serial_port_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct imx_port *sport = platform_get_drvdata(pdev); + + /* disable wakeup from i.MX UART */ + serial_imx_enable_wakeup(sport, false); + + uart_resume_port(&imx_reg, &sport->port); + + return 0; +} + +static const struct dev_pm_ops imx_serial_port_pm_ops = { + .suspend_noirq = imx_serial_port_suspend_noirq, + .resume_noirq = imx_serial_port_resume_noirq, + .suspend = imx_serial_port_suspend, + .resume = imx_serial_port_resume, +}; + static struct platform_driver serial_imx_driver = { .probe = serial_imx_probe, .remove = serial_imx_remove, - .suspend = serial_imx_suspend, - .resume = serial_imx_resume, .id_table = imx_uart_devtype, .driver = { .name = "imx-uart", .of_match_table = imx_uart_dt_ids, + .pm = &imx_serial_port_pm_ops, }, }; |