diff options
Diffstat (limited to 'drivers/tty/serial/owl-uart.c')
| -rw-r--r-- | drivers/tty/serial/owl-uart.c | 60 |
1 files changed, 52 insertions, 8 deletions
diff --git a/drivers/tty/serial/owl-uart.c b/drivers/tty/serial/owl-uart.c index 42c8cc93b603..fde39cc1145d 100644 --- a/drivers/tty/serial/owl-uart.c +++ b/drivers/tty/serial/owl-uart.c @@ -12,6 +12,7 @@ #include <linux/console.h> #include <linux/delay.h> #include <linux/io.h> +#include <linux/iopoll.h> #include <linux/module.h> #include <linux/of.h> #include <linux/platform_device.h> @@ -62,6 +63,9 @@ #define OWL_UART_STAT_TRFL_MASK GENMASK(16, 11) #define OWL_UART_STAT_UTBB BIT(17) +#define OWL_UART_POLL_USEC 5 +#define OWL_UART_TIMEOUT_USEC 10000 + static struct uart_driver owl_uart_driver; struct owl_uart_info { @@ -180,9 +184,6 @@ static void owl_uart_send_chars(struct uart_port *port) struct circ_buf *xmit = &port->state->xmit; unsigned int ch; - if (uart_tx_stopped(port)) - return; - if (port->x_char) { while (!(owl_uart_read(port, OWL_UART_STAT) & OWL_UART_STAT_TFFU)) cpu_relax(); @@ -191,13 +192,16 @@ static void owl_uart_send_chars(struct uart_port *port) port->x_char = 0; } + if (uart_tx_stopped(port)) + return; + while (!(owl_uart_read(port, OWL_UART_STAT) & OWL_UART_STAT_TFFU)) { if (uart_circ_empty(xmit)) break; ch = xmit->buf[xmit->tail]; owl_uart_write(port, ch, OWL_UART_TXDAT); - xmit->tail = (xmit->tail + 1) & (SERIAL_XMIT_SIZE - 1); + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); port->icount.tx++; } @@ -243,9 +247,7 @@ static void owl_uart_receive_chars(struct uart_port *port) stat = owl_uart_read(port, OWL_UART_STAT); } - spin_unlock(&port->lock); tty_flip_buffer_push(&port->state->port); - spin_lock(&port->lock); } static irqreturn_t owl_uart_irq(int irq, void *dev_id) @@ -326,7 +328,7 @@ static void owl_uart_change_baudrate(struct owl_uart_port *owl_port, static void owl_uart_set_termios(struct uart_port *port, struct ktermios *termios, - struct ktermios *old) + const struct ktermios *old) { struct owl_uart_port *owl_port = to_owl_uart_port(port); unsigned int baud; @@ -461,6 +463,36 @@ static void owl_uart_config_port(struct uart_port *port, int flags) } } +#ifdef CONFIG_CONSOLE_POLL + +static int owl_uart_poll_get_char(struct uart_port *port) +{ + if (owl_uart_read(port, OWL_UART_STAT) & OWL_UART_STAT_RFEM) + return NO_POLL_CHAR; + + return owl_uart_read(port, OWL_UART_RXDAT); +} + +static void owl_uart_poll_put_char(struct uart_port *port, unsigned char ch) +{ + u32 reg; + int ret; + + /* Wait while FIFO is full or timeout */ + ret = readl_poll_timeout_atomic(port->membase + OWL_UART_STAT, reg, + !(reg & OWL_UART_STAT_TFFU), + OWL_UART_POLL_USEC, + OWL_UART_TIMEOUT_USEC); + if (ret == -ETIMEDOUT) { + dev_err(port->dev, "Timeout waiting while UART TX FULL\n"); + return; + } + + owl_uart_write(port, ch, OWL_UART_TXDAT); +} + +#endif /* CONFIG_CONSOLE_POLL */ + static const struct uart_ops owl_uart_ops = { .set_mctrl = owl_uart_set_mctrl, .get_mctrl = owl_uart_get_mctrl, @@ -476,11 +508,15 @@ static const struct uart_ops owl_uart_ops = { .request_port = owl_uart_request_port, .release_port = owl_uart_release_port, .verify_port = owl_uart_verify_port, +#ifdef CONFIG_CONSOLE_POLL + .poll_get_char = owl_uart_poll_get_char, + .poll_put_char = owl_uart_poll_put_char, +#endif }; #ifdef CONFIG_SERIAL_OWL_CONSOLE -static void owl_console_putchar(struct uart_port *port, int ch) +static void owl_console_putchar(struct uart_port *port, unsigned char ch) { if (!port->membase) return; @@ -680,6 +716,12 @@ static int owl_uart_probe(struct platform_device *pdev) return PTR_ERR(owl_port->clk); } + ret = clk_prepare_enable(owl_port->clk); + if (ret) { + dev_err(&pdev->dev, "could not enable clk\n"); + return ret; + } + owl_port->port.dev = &pdev->dev; owl_port->port.line = pdev->id; owl_port->port.type = PORT_OWL; @@ -689,6 +731,7 @@ static int owl_uart_probe(struct platform_device *pdev) owl_port->port.uartclk = clk_get_rate(owl_port->clk); if (owl_port->port.uartclk == 0) { dev_err(&pdev->dev, "clock rate is zero\n"); + clk_disable_unprepare(owl_port->clk); return -EINVAL; } owl_port->port.flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP | UPF_LOW_LATENCY; @@ -712,6 +755,7 @@ static int owl_uart_remove(struct platform_device *pdev) uart_remove_one_port(&owl_uart_driver, &owl_port->port); owl_uart_ports[pdev->id] = NULL; + clk_disable_unprepare(owl_port->clk); return 0; } |