Reserve 5 bit serial for multidrop in Atmel Serial driver

2 files changed, 53 insertions, 4 deletions

diff --git a/recipes-kernel/linux/linux-at91-4.9.87/mtcdt/linux-4.9-mtcdt-atmel-multidrop.patch b/recipes-kernel/linux/linux-at91-4.9.87/mtcdt/linux-4.9-mtcdt-atmel-multidrop.patch
new file mode 100644
index 0000000..188c5cf
--- /dev/null
+++ b/recipes-kernel/linux/linux-at91-4.9.87/mtcdt/linux-4.9-mtcdt-atmel-multidrop.patch
@@ -0,0 +1,48 @@
+ This patch was derived from the Vizzini driver and this patch:
+
+ https://www.spinics.net/lists/linux-serial/msg25999.html
+
+ Since all prior versions of MTCDT used the Vizzini driver,
+ the mapping of 5 bit serial to multidrop (9 bit serial) was
+ used.
+
+ The purpose of this patch is to reserve the Atmel 5 bit mode
+ for 9 bit usage on MTCDT MTAC-MFSER.
+===========================================================================================
+diff --git orig/drivers/tty/serial/atmel_serial.c new/drivers/tty/serial/atmel_serial.c
+index 1297853..cd7987b 100644
+--- orig/drivers/tty/serial/atmel_serial.c
++++ new/drivers/tty/serial/atmel_serial.c
+@@ -2073,7 +2073,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
+ {
+ 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ 	unsigned long flags;
+-	unsigned int old_mode, mode, imr, quot, baud, div, cd, fp = 0;
++	unsigned int old_mode, mode, mdrop, imr, quot, baud, div, cd, fp = 0;
+ 
+ 	/* save the current mode register */
+ 	mode = old_mode = atmel_uart_readl(port, ATMEL_US_MR);
+@@ -2084,10 +2084,12 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
+ 
+ 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
+ 
++	mdrop = 0;
+ 	/* byte size */
+ 	switch (termios->c_cflag & CSIZE) {
+ 	case CS5:
+-		mode |= ATMEL_US_CHRL_5;
++		mode |= ATMEL_US_PAR_MULTI_DROP;
++		mdrop = ATMEL_US_SENDA;
+ 		break;
+ 	case CS6:
+ 		mode |= ATMEL_US_CHRL_6;
+@@ -2246,7 +2248,8 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
+ 
+ 	atmel_uart_writel(port, ATMEL_US_BRGR, quot);
+ 	atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
+-	atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXEN | ATMEL_US_RXEN);
++	atmel_uart_writel(port, ATMEL_US_CR,
++				mdrop | ATMEL_US_TXEN | ATMEL_US_RXEN);
+ 	atmel_port->tx_stopped = false;
+ 
+ 	/* restore interrupts */
diff --git a/recipes-kernel/linux/linux-at91_4.9.87.bb b/recipes-kernel/linux/linux-at91_4.9.87.bb
index a1cb6a3..ec942ec 100644
--- a/recipes-kernel/linux/linux-at91_4.9.87.bb
+++ b/recipes-kernel/linux/linux-at91_4.9.87.bb
@@ -19,7 +19,7 @@ RDEPENDS_kernel-modules_remove = "kernel-module-softdog"
 FILESEXTRAPATHS_prepend := "${THISDIR}/${P}:"
 KERNEL_EXTRA_ARGS ="LOADADDR=0x20008000"
 
-PR = "r15"
+PR = "r16"
 PKGR_kernel-module-i2c-at91 = "${PR}a${EXTENDPRAUTO}"
 PKGR_kernel-module-atmel-mci = "${PR}a${EXTENDPRAUTO}"
 KERNEL_VERSION = "${PV}"
@@ -41,9 +41,9 @@ COMMON_PATCHES = " \
 		  file://defconfig \
 		  file://linux-4.9-pps-gpio.patch \
 		  file://linux-4.9-at91sam9_wdt-10second-timeout.patch \
-                  file://linux-4.9-spidev_squack.patch \
-                  file://linux-4.9-add-num_accessory_ports-config-option.patch \
-                  file://linux-4.9-cdc-acm-ignore-exar-devices.patch \
+		  file://linux-4.9-spidev_squack.patch \
+		  file://linux-4.9-add-num_accessory_ports-config-option.patch \
+		  file://linux-4.9-cdc-acm-ignore-exar-devices.patch \
 		  file://EXTRAVERSION.patch \
 		  file://linux-4.9-ledtrig-netdev.patch \
 		  file://linux-4.9-addl-time-for-pmeccerrloc.patch \
@@ -54,6 +54,7 @@ COMMON_PATCHES = " \
 		  file://0002-linux-4.9-telit_print_qmi_wwan.patch \
 		  file://make-kernel-reproducible.patch \
 		  file://linux-4.9-atmel-mci-end.patch \
+		  file://linux-4.9-mtcdt-atmel-multidrop.patch \
 		  file://i2c-at91.conf \
 		 "