From 43c51bb573aab63cd67ad7216dc0b849036bc47a Mon Sep 17 00:00:00 2001 From: Florian Vallee Date: Tue, 19 Jul 2016 16:29:36 +0200 Subject: [PATCH] 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 Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/sc16is7xx.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c index f36e6df2fa90..a9d94f7cf683 100644 --- a/drivers/tty/serial/sc16is7xx.c +++ b/drivers/tty/serial/sc16is7xx.c @@ -1205,6 +1205,10 @@ static int sc16is7xx_probe(struct device *dev, } #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 @@ static int sc16is7xx_probe(struct device *dev, 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); } -- 2.39.5