From 9eb90d57b55a0af499e8fee14ef942e80ad5f6f9 Mon Sep 17 00:00:00 2001 From: Pascal Huerst Date: Fri, 29 May 2020 07:50:58 +0200 Subject: [PATCH] sc16is7xx: Add flag to activate IrDA mode This series of uart controllers is able to work in IrDA mode. Add per-port flag to the device-tree to enable that feature if needed. Signed-off-by: Pascal Huerst Signed-off-by: Daniel Mack Link: https://lore.kernel.org/r/20200529055058.1606910-3-daniel@zonque.org 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 8fee0e8b851f..d2e5c6c86643 100644 --- a/drivers/tty/serial/sc16is7xx.c +++ b/drivers/tty/serial/sc16is7xx.c @@ -315,6 +315,7 @@ struct sc16is7xx_one { struct kthread_work tx_work; struct kthread_work reg_work; struct sc16is7xx_one_config config; + bool irda_mode; }; struct sc16is7xx_port { @@ -986,6 +987,7 @@ static int sc16is7xx_config_rs485(struct uart_port *port, static int sc16is7xx_startup(struct uart_port *port) { + struct sc16is7xx_one *one = to_sc16is7xx_one(port, port); struct sc16is7xx_port *s = dev_get_drvdata(port->dev); unsigned int val; @@ -1024,6 +1026,13 @@ static int sc16is7xx_startup(struct uart_port *port) /* Now, initialize the UART */ sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, SC16IS7XX_LCR_WORD_LEN_8); + /* Enable IrDA mode if requested in DT */ + /* This bit must be written with LCR[7] = 0 */ + sc16is7xx_port_update(port, SC16IS7XX_MCR_REG, + SC16IS7XX_MCR_IRDA_BIT, + one->irda_mode ? + SC16IS7XX_MCR_IRDA_BIT : 0); + /* Enable the Rx and Tx FIFO */ sc16is7xx_port_update(port, SC16IS7XX_EFCR_REG, SC16IS7XX_EFCR_RXDISABLE_BIT | @@ -1304,6 +1313,17 @@ static int sc16is7xx_probe(struct device *dev, sc16is7xx_power(&s->p[i].port, 0); } + if (dev->of_node) { + struct property *prop; + const __be32 *p; + u32 u; + + of_property_for_each_u32(dev->of_node, "irda-mode-ports", + prop, p, u) + if (u < devtype->nr_uart) + s->p[u].irda_mode = true; + } + /* * Setup interrupt. We first try to acquire the IRQ line as level IRQ. * If that succeeds, we can allow sharing the interrupt as well.