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path: root/drivers/tty/serial/sh-sci.c
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Diffstat (limited to 'drivers/tty/serial/sh-sci.c')
-rw-r--r--drivers/tty/serial/sh-sci.c85
1 files changed, 55 insertions, 30 deletions
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index fdbbff547106..c181eb37f985 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -160,6 +160,7 @@ struct sci_port {
#define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
static struct sci_port sci_ports[SCI_NPORTS];
+static unsigned long sci_ports_in_use;
static struct uart_driver sci_uart_driver;
static inline struct sci_port *
@@ -2390,6 +2391,27 @@ done:
uart_update_timeout(port, termios->c_cflag, baud);
+ /* byte size and parity */
+ switch (termios->c_cflag & CSIZE) {
+ case CS5:
+ bits = 7;
+ break;
+ case CS6:
+ bits = 8;
+ break;
+ case CS7:
+ bits = 9;
+ break;
+ default:
+ bits = 10;
+ break;
+ }
+
+ if (termios->c_cflag & CSTOPB)
+ bits++;
+ if (termios->c_cflag & PARENB)
+ bits++;
+
if (best_clk >= 0) {
if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
switch (srr + 1) {
@@ -2406,8 +2428,27 @@ done:
serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
serial_port_out(port, SCSMR, smr_val);
serial_port_out(port, SCBRR, brr);
- if (sci_getreg(port, HSSRR)->size)
- serial_port_out(port, HSSRR, srr | HSCIF_SRE);
+ if (sci_getreg(port, HSSRR)->size) {
+ unsigned int hssrr = srr | HSCIF_SRE;
+ /* Calculate deviation from intended rate at the
+ * center of the last stop bit in sampling clocks.
+ */
+ int last_stop = bits * 2 - 1;
+ int deviation = min_err * srr * last_stop / 2 / baud;
+
+ if (abs(deviation) >= 2) {
+ /* At least two sampling clocks off at the
+ * last stop bit; we can increase the error
+ * margin by shifting the sampling point.
+ */
+ int shift = min(-8, max(7, deviation / 2));
+
+ hssrr |= (shift << HSCIF_SRHP_SHIFT) &
+ HSCIF_SRHP_MASK;
+ hssrr |= HSCIF_SRDE;
+ }
+ serial_port_out(port, HSSRR, hssrr);
+ }
/* Wait one bit interval */
udelay((1000000 + (baud - 1)) / baud);
@@ -2474,27 +2515,6 @@ done:
* value obtained by this formula is too small. Therefore, if the value
* is smaller than 20ms, use 20ms as the timeout value for DMA.
*/
- /* byte size and parity */
- switch (termios->c_cflag & CSIZE) {
- case CS5:
- bits = 7;
- break;
- case CS6:
- bits = 8;
- break;
- case CS7:
- bits = 9;
- break;
- default:
- bits = 10;
- break;
- }
-
- if (termios->c_cflag & CSTOPB)
- bits++;
- if (termios->c_cflag & PARENB)
- bits++;
-
s->rx_frame = (10000 * bits) / (baud / 100);
#ifdef CONFIG_SERIAL_SH_SCI_DMA
s->rx_timeout = s->buf_len_rx * 2 * s->rx_frame;
@@ -2704,8 +2724,8 @@ found:
dev_dbg(dev, "failed to get %s (%ld)\n", clk_names[i],
PTR_ERR(clk));
else
- dev_dbg(dev, "clk %s is %pC rate %pCr\n", clk_names[i],
- clk, clk);
+ dev_dbg(dev, "clk %s is %pC rate %lu\n", clk_names[i],
+ clk, clk_get_rate(clk));
sci_port->clks[i] = IS_ERR(clk) ? NULL : clk;
}
return 0;
@@ -2890,16 +2910,15 @@ static void serial_console_write(struct console *co, const char *s,
unsigned long flags;
int locked = 1;
- local_irq_save(flags);
#if defined(SUPPORT_SYSRQ)
if (port->sysrq)
locked = 0;
else
#endif
if (oops_in_progress)
- locked = spin_trylock(&port->lock);
+ locked = spin_trylock_irqsave(&port->lock, flags);
else
- spin_lock(&port->lock);
+ spin_lock_irqsave(&port->lock, flags);
/* first save SCSCR then disable interrupts, keep clock source */
ctrl = serial_port_in(port, SCSCR);
@@ -2919,8 +2938,7 @@ static void serial_console_write(struct console *co, const char *s,
serial_port_out(port, SCSCR, ctrl);
if (locked)
- spin_unlock(&port->lock);
- local_irq_restore(flags);
+ spin_unlock_irqrestore(&port->lock, flags);
}
static int serial_console_setup(struct console *co, char *options)
@@ -3026,6 +3044,7 @@ static int sci_remove(struct platform_device *dev)
{
struct sci_port *port = platform_get_drvdata(dev);
+ sci_ports_in_use &= ~BIT(port->port.line);
uart_remove_one_port(&sci_uart_driver, &port->port);
sci_cleanup_single(port);
@@ -3107,6 +3126,8 @@ static struct plat_sci_port *sci_parse_dt(struct platform_device *pdev,
/* Get the line number from the aliases node. */
id = of_alias_get_id(np, "serial");
+ if (id < 0 && ~sci_ports_in_use)
+ id = ffz(sci_ports_in_use);
if (id < 0) {
dev_err(&pdev->dev, "failed to get alias id (%d)\n", id);
return NULL;
@@ -3141,6 +3162,9 @@ static int sci_probe_single(struct platform_device *dev,
dev_notice(&dev->dev, "Consider bumping CONFIG_SERIAL_SH_SCI_NR_UARTS!\n");
return -EINVAL;
}
+ BUILD_BUG_ON(SCI_NPORTS > sizeof(sci_ports_in_use) * 8);
+ if (sci_ports_in_use & BIT(index))
+ return -EBUSY;
mutex_lock(&sci_uart_registration_lock);
if (!sci_uart_driver.state) {
@@ -3239,6 +3263,7 @@ static int sci_probe(struct platform_device *dev)
sh_bios_gdb_detach();
#endif
+ sci_ports_in_use |= BIT(dev_id);
return 0;
}