diff options
Diffstat (limited to 'drivers/tty/serial/8250')
| -rw-r--r-- | drivers/tty/serial/8250/8250.h | 12 | ||||
| -rw-r--r-- | drivers/tty/serial/8250/8250_bcm7271.c | 18 | ||||
| -rw-r--r-- | drivers/tty/serial/8250/8250_core.c | 1 | ||||
| -rw-r--r-- | drivers/tty/serial/8250/8250_em.c | 113 | ||||
| -rw-r--r-- | drivers/tty/serial/8250/8250_port.c | 22 | ||||
| -rw-r--r-- | drivers/tty/serial/8250/8250_tegra.c | 1 |
6 files changed, 135 insertions, 32 deletions
diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h index 287153d32536..1e8fe44a7099 100644 --- a/drivers/tty/serial/8250/8250.h +++ b/drivers/tty/serial/8250/8250.h @@ -365,6 +365,13 @@ static inline void serial8250_do_prepare_rx_dma(struct uart_8250_port *p) if (dma->prepare_rx_dma) dma->prepare_rx_dma(p); } + +static inline bool serial8250_tx_dma_running(struct uart_8250_port *p) +{ + struct uart_8250_dma *dma = p->dma; + + return dma && dma->tx_running; +} #else static inline int serial8250_tx_dma(struct uart_8250_port *p) { @@ -380,6 +387,11 @@ static inline int serial8250_request_dma(struct uart_8250_port *p) return -1; } static inline void serial8250_release_dma(struct uart_8250_port *p) { } + +static inline bool serial8250_tx_dma_running(struct uart_8250_port *p) +{ + return false; +} #endif static inline int ns16550a_goto_highspeed(struct uart_8250_port *up) diff --git a/drivers/tty/serial/8250/8250_bcm7271.c b/drivers/tty/serial/8250/8250_bcm7271.c index ed5a94747692..f801b1f5b46c 100644 --- a/drivers/tty/serial/8250/8250_bcm7271.c +++ b/drivers/tty/serial/8250/8250_bcm7271.c @@ -1014,14 +1014,16 @@ static int brcmuart_probe(struct platform_device *pdev) /* See if a Baud clock has been specified */ baud_mux_clk = of_clk_get_by_name(np, "sw_baud"); if (IS_ERR(baud_mux_clk)) { - if (PTR_ERR(baud_mux_clk) == -EPROBE_DEFER) - return -EPROBE_DEFER; + if (PTR_ERR(baud_mux_clk) == -EPROBE_DEFER) { + ret = -EPROBE_DEFER; + goto release_dma; + } dev_dbg(dev, "BAUD MUX clock not specified\n"); } else { dev_dbg(dev, "BAUD MUX clock found\n"); ret = clk_prepare_enable(baud_mux_clk); if (ret) - return ret; + goto release_dma; priv->baud_mux_clk = baud_mux_clk; init_real_clk_rates(dev, priv); clk_rate = priv->default_mux_rate; @@ -1029,7 +1031,8 @@ static int brcmuart_probe(struct platform_device *pdev) if (clk_rate == 0) { dev_err(dev, "clock-frequency or clk not defined\n"); - return -EINVAL; + ret = -EINVAL; + goto release_dma; } dev_dbg(dev, "DMA is %senabled\n", priv->dma_enabled ? "" : "not "); @@ -1116,7 +1119,9 @@ err1: serial8250_unregister_port(priv->line); err: brcmuart_free_bufs(dev, priv); - brcmuart_arbitration(priv, 0); +release_dma: + if (priv->dma_enabled) + brcmuart_arbitration(priv, 0); return ret; } @@ -1128,7 +1133,8 @@ static int brcmuart_remove(struct platform_device *pdev) hrtimer_cancel(&priv->hrt); serial8250_unregister_port(priv->line); brcmuart_free_bufs(&pdev->dev, priv); - brcmuart_arbitration(priv, 0); + if (priv->dma_enabled) + brcmuart_arbitration(priv, 0); return 0; } diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index ab63c308be0a..13bf535eedcd 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -1158,6 +1158,7 @@ void serial8250_unregister_port(int line) uart->port.type = PORT_UNKNOWN; uart->port.dev = &serial8250_isa_devs->dev; uart->capabilities = 0; + serial8250_init_port(uart); serial8250_apply_quirks(uart); uart_add_one_port(&serial8250_reg, &uart->port); } else { diff --git a/drivers/tty/serial/8250/8250_em.c b/drivers/tty/serial/8250/8250_em.c index d94c3811a8f7..25a9ecf26be6 100644 --- a/drivers/tty/serial/8250/8250_em.c +++ b/drivers/tty/serial/8250/8250_em.c @@ -13,36 +13,49 @@ #include <linux/serial_reg.h> #include <linux/platform_device.h> #include <linux/clk.h> -#include <linux/slab.h> #include "8250.h" #define UART_DLL_EM 9 #define UART_DLM_EM 10 +#define UART_HCR0_EM 11 + +/* + * A high value for UART_FCR_EM avoids overlapping with existing UART_* + * register defines. UART_FCR_EM_HW is the real HW register offset. + */ +#define UART_FCR_EM 0x10003 +#define UART_FCR_EM_HW 3 + +#define UART_HCR0_EM_SW_RESET BIT(7) /* SW Reset */ struct serial8250_em_priv { - struct clk *sclk; int line; }; -static void serial8250_em_serial_out(struct uart_port *p, int offset, int value) +static void serial8250_em_serial_out_helper(struct uart_port *p, int offset, + int value) { switch (offset) { case UART_TX: /* TX @ 0x00 */ writeb(value, p->membase); break; - case UART_FCR: /* FCR @ 0x0c (+1) */ case UART_LCR: /* LCR @ 0x10 (+1) */ case UART_MCR: /* MCR @ 0x14 (+1) */ case UART_SCR: /* SCR @ 0x20 (+1) */ writel(value, p->membase + ((offset + 1) << 2)); break; + case UART_FCR_EM: + writel(value, p->membase + (UART_FCR_EM_HW << 2)); + break; case UART_IER: /* IER @ 0x04 */ value &= 0x0f; /* only 4 valid bits - not Xscale */ fallthrough; case UART_DLL_EM: /* DLL @ 0x24 (+9) */ case UART_DLM_EM: /* DLM @ 0x28 (+9) */ + case UART_HCR0_EM: /* HCR0 @ 0x2c */ writel(value, p->membase + (offset << 2)); + break; } } @@ -51,20 +64,81 @@ static unsigned int serial8250_em_serial_in(struct uart_port *p, int offset) switch (offset) { case UART_RX: /* RX @ 0x00 */ return readb(p->membase); + case UART_LCR: /* LCR @ 0x10 (+1) */ case UART_MCR: /* MCR @ 0x14 (+1) */ case UART_LSR: /* LSR @ 0x18 (+1) */ case UART_MSR: /* MSR @ 0x1c (+1) */ case UART_SCR: /* SCR @ 0x20 (+1) */ return readl(p->membase + ((offset + 1) << 2)); + case UART_FCR_EM: + return readl(p->membase + (UART_FCR_EM_HW << 2)); case UART_IER: /* IER @ 0x04 */ case UART_IIR: /* IIR @ 0x08 */ case UART_DLL_EM: /* DLL @ 0x24 (+9) */ case UART_DLM_EM: /* DLM @ 0x28 (+9) */ + case UART_HCR0_EM: /* HCR0 @ 0x2c */ return readl(p->membase + (offset << 2)); } return 0; } +static void serial8250_em_reg_update(struct uart_port *p, int off, int value) +{ + unsigned int ier, fcr, lcr, mcr, hcr0; + + ier = serial8250_em_serial_in(p, UART_IER); + fcr = serial8250_em_serial_in(p, UART_FCR_EM); + lcr = serial8250_em_serial_in(p, UART_LCR); + mcr = serial8250_em_serial_in(p, UART_MCR); + hcr0 = serial8250_em_serial_in(p, UART_HCR0_EM); + + serial8250_em_serial_out_helper(p, UART_FCR_EM, fcr | + UART_FCR_CLEAR_RCVR | + UART_FCR_CLEAR_XMIT); + serial8250_em_serial_out_helper(p, UART_HCR0_EM, hcr0 | + UART_HCR0_EM_SW_RESET); + serial8250_em_serial_out_helper(p, UART_HCR0_EM, hcr0 & + ~UART_HCR0_EM_SW_RESET); + + switch (off) { + case UART_FCR_EM: + fcr = value; + break; + case UART_LCR: + lcr = value; + break; + case UART_MCR: + mcr = value; + break; + } + + serial8250_em_serial_out_helper(p, UART_IER, ier); + serial8250_em_serial_out_helper(p, UART_FCR_EM, fcr); + serial8250_em_serial_out_helper(p, UART_MCR, mcr); + serial8250_em_serial_out_helper(p, UART_LCR, lcr); + serial8250_em_serial_out_helper(p, UART_HCR0_EM, hcr0); +} + +static void serial8250_em_serial_out(struct uart_port *p, int offset, int value) +{ + switch (offset) { + case UART_TX: + case UART_SCR: + case UART_IER: + case UART_DLL_EM: + case UART_DLM_EM: + serial8250_em_serial_out_helper(p, offset, value); + break; + case UART_FCR: + serial8250_em_reg_update(p, UART_FCR_EM, value); + break; + case UART_LCR: + case UART_MCR: + serial8250_em_reg_update(p, offset, value); + break; + } +} + static int serial8250_em_serial_dl_read(struct uart_8250_port *up) { return serial_in(up, UART_DLL_EM) | serial_in(up, UART_DLM_EM) << 8; @@ -79,8 +153,10 @@ static void serial8250_em_serial_dl_write(struct uart_8250_port *up, int value) static int serial8250_em_probe(struct platform_device *pdev) { struct serial8250_em_priv *priv; + struct device *dev = &pdev->dev; struct uart_8250_port up; struct resource *regs; + struct clk *sclk; int irq, ret; irq = platform_get_irq(pdev, 0); @@ -88,31 +164,26 @@ static int serial8250_em_probe(struct platform_device *pdev) return irq; regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (!regs) { - dev_err(&pdev->dev, "missing registers\n"); - return -EINVAL; - } + if (!regs) + return dev_err_probe(dev, -EINVAL, "missing registers\n"); - priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; - priv->sclk = devm_clk_get(&pdev->dev, "sclk"); - if (IS_ERR(priv->sclk)) { - dev_err(&pdev->dev, "unable to get clock\n"); - return PTR_ERR(priv->sclk); - } + sclk = devm_clk_get_enabled(dev, "sclk"); + if (IS_ERR(sclk)) + return dev_err_probe(dev, PTR_ERR(sclk), "unable to get clock\n"); memset(&up, 0, sizeof(up)); up.port.mapbase = regs->start; up.port.irq = irq; up.port.type = PORT_16750; up.port.flags = UPF_FIXED_PORT | UPF_IOREMAP | UPF_FIXED_TYPE; - up.port.dev = &pdev->dev; + up.port.dev = dev; up.port.private_data = priv; - clk_prepare_enable(priv->sclk); - up.port.uartclk = clk_get_rate(priv->sclk); + up.port.uartclk = clk_get_rate(sclk); up.port.iotype = UPIO_MEM32; up.port.serial_in = serial8250_em_serial_in; @@ -121,11 +192,8 @@ static int serial8250_em_probe(struct platform_device *pdev) up.dl_write = serial8250_em_serial_dl_write; ret = serial8250_register_8250_port(&up); - if (ret < 0) { - dev_err(&pdev->dev, "unable to register 8250 port\n"); - clk_disable_unprepare(priv->sclk); - return ret; - } + if (ret < 0) + return dev_err_probe(dev, ret, "unable to register 8250 port\n"); priv->line = ret; platform_set_drvdata(pdev, priv); @@ -137,7 +205,6 @@ static int serial8250_em_remove(struct platform_device *pdev) struct serial8250_em_priv *priv = platform_get_drvdata(pdev); serial8250_unregister_port(priv->line); - clk_disable_unprepare(priv->sclk); return 0; } diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index fa43df05342b..fe8d79c4ae95 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -15,6 +15,7 @@ #include <linux/moduleparam.h> #include <linux/ioport.h> #include <linux/init.h> +#include <linux/irq.h> #include <linux/console.h> #include <linux/gpio/consumer.h> #include <linux/sysrq.h> @@ -1903,6 +1904,17 @@ EXPORT_SYMBOL_GPL(serial8250_modem_status); static bool handle_rx_dma(struct uart_8250_port *up, unsigned int iir) { switch (iir & 0x3f) { + case UART_IIR_THRI: + /* + * Postpone DMA or not decision to IIR_RDI or IIR_RX_TIMEOUT + * because it's impossible to do an informed decision about + * that with IIR_THRI. + * + * This also fixes one known DMA Rx corruption issue where + * DR is asserted but DMA Rx only gets a corrupted zero byte + * (too early DR?). + */ + return false; case UART_IIR_RDI: if (!up->dma->rx_running) break; @@ -1921,6 +1933,7 @@ static bool handle_rx_dma(struct uart_8250_port *up, unsigned int iir) int serial8250_handle_irq(struct uart_port *port, unsigned int iir) { struct uart_8250_port *up = up_to_u8250p(port); + struct tty_port *tport = &port->state->port; bool skip_rx = false; unsigned long flags; u16 status; @@ -1946,6 +1959,8 @@ int serial8250_handle_irq(struct uart_port *port, unsigned int iir) skip_rx = true; if (status & (UART_LSR_DR | UART_LSR_BI) && !skip_rx) { + if (irqd_is_wakeup_set(irq_get_irq_data(port->irq))) + pm_wakeup_event(tport->tty->dev, 0); if (!up->dma || handle_rx_dma(up, iir)) status = serial8250_rx_chars(up, status); } @@ -2005,18 +2020,19 @@ static int serial8250_tx_threshold_handle_irq(struct uart_port *port) static unsigned int serial8250_tx_empty(struct uart_port *port) { struct uart_8250_port *up = up_to_u8250p(port); + unsigned int result = 0; unsigned long flags; - u16 lsr; serial8250_rpm_get(up); spin_lock_irqsave(&port->lock, flags); - lsr = serial_lsr_in(up); + if (!serial8250_tx_dma_running(up) && uart_lsr_tx_empty(serial_lsr_in(up))) + result = TIOCSER_TEMT; spin_unlock_irqrestore(&port->lock, flags); serial8250_rpm_put(up); - return uart_lsr_tx_empty(lsr) ? TIOCSER_TEMT : 0; + return result; } unsigned int serial8250_do_get_mctrl(struct uart_port *port) diff --git a/drivers/tty/serial/8250/8250_tegra.c b/drivers/tty/serial/8250/8250_tegra.c index e7cddeec9d8e..2509e7f74ccf 100644 --- a/drivers/tty/serial/8250/8250_tegra.c +++ b/drivers/tty/serial/8250/8250_tegra.c @@ -11,6 +11,7 @@ #include <linux/delay.h> #include <linux/io.h> #include <linux/module.h> +#include <linux/of.h> #include <linux/reset.h> #include <linux/slab.h> |