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authorSimon Goldschmidt <simon.k.r.goldschmidt@gmail.com>2018-11-02 21:28:08 +0100
committerTom Rini <trini@konsulko.com>2018-11-16 16:52:00 -0500
commit9ad3b049ed9f8b97d76b0e5986e7258bb0a0c92e (patch)
treef072f36a4a491b019cf39ea79daeff1fd598be5c /drivers/serial
parent0a16868757f40a4b5578c0cf65d3bfc8d3fd7dc0 (diff)
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serial: ns16550: add setconfig support
Add possibility to update the serial parity used. Signed-off-by: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com> Reviewed-by: Simon Glass <sjg@chromium.org> Reviewed-by: Hannes Schmelzer <hannes.schmelzer@br-automation.com>
Diffstat (limited to 'drivers/serial')
-rw-r--r--drivers/serial/ns16550.c43
1 files changed, 41 insertions, 2 deletions
diff --git a/drivers/serial/ns16550.c b/drivers/serial/ns16550.c
index 1e6fc6c668..f21c240e64 100644
--- a/drivers/serial/ns16550.c
+++ b/drivers/serial/ns16550.c
@@ -148,10 +148,13 @@ int ns16550_calc_divisor(NS16550_t port, int clock, int baudrate)
static void NS16550_setbrg(NS16550_t com_port, int baud_divisor)
{
- serial_out(UART_LCR_BKSE | UART_LCRVAL, &com_port->lcr);
+ /* to keep serial format, read lcr before writing BKSE */
+ int lcr_val = serial_in(&com_port->lcr) & ~UART_LCR_BKSE;
+
+ serial_out(UART_LCR_BKSE | lcr_val, &com_port->lcr);
serial_out(baud_divisor & 0xff, &com_port->dll);
serial_out((baud_divisor >> 8) & 0xff, &com_port->dlm);
- serial_out(UART_LCRVAL, &com_port->lcr);
+ serial_out(lcr_val, &com_port->lcr);
}
void NS16550_init(NS16550_t com_port, int baud_divisor)
@@ -181,6 +184,8 @@ void NS16550_init(NS16550_t com_port, int baud_divisor)
serial_out(UART_MCRVAL, &com_port->mcr);
serial_out(ns16550_getfcr(com_port), &com_port->fcr);
+ /* initialize serial config to 8N1 before writing baudrate */
+ serial_out(UART_LCRVAL, &com_port->lcr);
if (baud_divisor != -1)
NS16550_setbrg(com_port, baud_divisor);
#if defined(CONFIG_ARCH_OMAP2PLUS) || defined(CONFIG_SOC_DA8XX) || \
@@ -348,6 +353,39 @@ static int ns16550_serial_setbrg(struct udevice *dev, int baudrate)
return 0;
}
+static int ns16550_serial_setconfig(struct udevice *dev, uint serial_config)
+{
+ struct NS16550 *const com_port = dev_get_priv(dev);
+ int lcr_val = UART_LCR_WLS_8;
+ uint parity = SERIAL_GET_PARITY(serial_config);
+ uint bits = SERIAL_GET_BITS(serial_config);
+ uint stop = SERIAL_GET_STOP(serial_config);
+
+ /*
+ * only parity config is implemented, check if other serial settings
+ * are the default one.
+ */
+ if (bits != SERIAL_8_BITS || stop != SERIAL_ONE_STOP)
+ return -ENOTSUPP; /* not supported in driver*/
+
+ switch (parity) {
+ case SERIAL_PAR_NONE:
+ /* no bits to add */
+ break;
+ case SERIAL_PAR_ODD:
+ lcr_val |= UART_LCR_PEN;
+ break;
+ case SERIAL_PAR_EVEN:
+ lcr_val |= UART_LCR_PEN | UART_LCR_EPS;
+ break;
+ default:
+ return -ENOTSUPP; /* not supported in driver*/
+ }
+
+ serial_out(lcr_val, &com_port->lcr);
+ return 0;
+}
+
int ns16550_serial_probe(struct udevice *dev)
{
struct NS16550 *const com_port = dev_get_priv(dev);
@@ -454,6 +492,7 @@ const struct dm_serial_ops ns16550_serial_ops = {
.pending = ns16550_serial_pending,
.getc = ns16550_serial_getc,
.setbrg = ns16550_serial_setbrg,
+ .setconfig = ns16550_serial_setconfig
};
#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)