leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

serial: sh-sci: make RX FIFO parameters tunable via sysfs

Browse Source 
Allows tuning of the RX FIFO fill threshold and timeout. (The latter is
only applicable to SCIFA and SCIFB).

Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ulrich Hecht 2017-02-03 11:38:19 +01:00 committed by Greg Kroah-Hartman
parent 039403765e
commit 5d23188a47
1 changed files with 87 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

87
drivers/tty/serial/sh-sci.c
View File

@ -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