From 5d23188a473da0b2fe6849ccf03578eebfead30e Mon Sep 17 00:00:00 2001 From: Ulrich Hecht Date: Fri, 3 Feb 2017 11:38:19 +0100 Subject: [PATCH] serial: sh-sci: make RX FIFO parameters tunable via sysfs Allows tuning of the RX FIFO fill threshold and timeout. (The latter is only applicable to SCIFA and SCIFB). Signed-off-by: Ulrich Hecht Reviewed-by: Geert Uytterhoeven Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/sh-sci.c | 87 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 87 insertions(+) diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index 4a165ed..f95a56c 100644 --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -1055,6 +1055,66 @@ static void rx_fifo_timer_fn(unsigned long arg) scif_set_rtrg(port, 1); } +static ssize_t rx_trigger_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct uart_port *port = dev_get_drvdata(dev); + struct sci_port *sci = to_sci_port(port); + + return sprintf(buf, "%d\n", sci->rx_trigger); +} + +static ssize_t rx_trigger_store(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t count) +{ + struct uart_port *port = dev_get_drvdata(dev); + struct sci_port *sci = to_sci_port(port); + long r; + + if (kstrtol(buf, 0, &r) == -EINVAL) + return -EINVAL; + sci->rx_trigger = scif_set_rtrg(port, r); + scif_set_rtrg(port, 1); + return count; +} + +static DEVICE_ATTR(rx_fifo_trigger, 0644, rx_trigger_show, rx_trigger_store); + +static ssize_t rx_fifo_timeout_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct uart_port *port = dev_get_drvdata(dev); + struct sci_port *sci = to_sci_port(port); + + return sprintf(buf, "%d\n", sci->rx_fifo_timeout); +} + +static ssize_t rx_fifo_timeout_store(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t count) +{ + struct uart_port *port = dev_get_drvdata(dev); + struct sci_port *sci = to_sci_port(port); + long r; + + if (kstrtol(buf, 0, &r) == -EINVAL) + return -EINVAL; + sci->rx_fifo_timeout = r; + scif_set_rtrg(port, 1); + if (r > 0) + setup_timer(&sci->rx_fifo_timer, rx_fifo_timer_fn, + (unsigned long)sci); + return count; +} + +static DEVICE_ATTR(rx_fifo_timeout, 0644, rx_fifo_timeout_show, rx_fifo_timeout_store); + + #ifdef CONFIG_SERIAL_SH_SCI_DMA static void sci_dma_tx_complete(void *arg) { @@ -2886,6 +2946,15 @@ static int sci_remove(struct platform_device *dev) sci_cleanup_single(port); + if (port->port.fifosize > 1) { + sysfs_remove_file(&dev->dev.kobj, + &dev_attr_rx_fifo_trigger.attr); + } + if (port->port.type == PORT_SCIFA || port->port.type == PORT_SCIFB) { + sysfs_remove_file(&dev->dev.kobj, + &dev_attr_rx_fifo_timeout.attr); + } + return 0; } @@ -3051,6 +3120,24 @@ static int sci_probe(struct platform_device *dev) if (ret) return ret; + if (sp->port.fifosize > 1) { + ret = sysfs_create_file(&dev->dev.kobj, + &dev_attr_rx_fifo_trigger.attr); + if (ret) + return ret; + } + if (sp->port.type == PORT_SCIFA || sp->port.type == PORT_SCIFB) { + ret = sysfs_create_file(&dev->dev.kobj, + &dev_attr_rx_fifo_timeout.attr); + if (ret) { + if (sp->port.fifosize > 1) { + sysfs_remove_file(&dev->dev.kobj, + &dev_attr_rx_fifo_trigger.attr); + } + return ret; + } + } + #ifdef CONFIG_SH_STANDARD_BIOS sh_bios_gdb_detach(); #endif -- 2.7.4