sc16is7xx: make sure device is in suspend once probed
Previously sc16is7xx_power was called in order to set the device to a
low power mode.
However since SC16IS7XX_EFR_ENABLE_BIT was not set beforehand this
suspend request had not effect.
Also, soft-reset the device prior to port initialization. It may
otherwise be in a state (interrupt pending, fifo not empty) which
prevents it from sleeping.
Signed-off-by: Florian Vallee <fvallee@eukrea.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index f36e6df..a9d94f7 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -1205,6 +1205,10 @@
}
#endif
+ /* reset device, purging any pending irq / data */
+ regmap_write(s->regmap, SC16IS7XX_IOCONTROL_REG << SC16IS7XX_REG_SHIFT,
+ SC16IS7XX_IOCONTROL_SRESET_BIT);
+
for (i = 0; i < devtype->nr_uart; ++i) {
s->p[i].line = i;
/* Initialize port data */
@@ -1234,6 +1238,22 @@
init_kthread_work(&s->p[i].reg_work, sc16is7xx_reg_proc);
/* Register port */
uart_add_one_port(&sc16is7xx_uart, &s->p[i].port);
+
+ /* Enable EFR */
+ sc16is7xx_port_write(&s->p[i].port, SC16IS7XX_LCR_REG,
+ SC16IS7XX_LCR_CONF_MODE_B);
+
+ regcache_cache_bypass(s->regmap, true);
+
+ /* Enable write access to enhanced features */
+ sc16is7xx_port_write(&s->p[i].port, SC16IS7XX_EFR_REG,
+ SC16IS7XX_EFR_ENABLE_BIT);
+
+ regcache_cache_bypass(s->regmap, false);
+
+ /* Restore access to general registers */
+ sc16is7xx_port_write(&s->p[i].port, SC16IS7XX_LCR_REG, 0x00);
+
/* Go to suspend mode */
sc16is7xx_power(&s->p[i].port, 0);
}