[PATCH v2 4/4] tty/serial: at91: use mctrl_gpio helpers
Richard Genoud
richard.genoud at gmail.com
Tue Feb 11 12:45:15 EST 2014
On sam9x5, dedicated CTS (and RTS) pins are unusable together with the
LCDC, the EMAC, or the MMC because they share the same line.
Moreover, the USART controller doesn't handle DTR/DSR/DCD/RI signals,
so we have to control them via GPIO.
This patch permits to use GPIOs to control the CTS/RTS/DTR/DSR/DCD/RI
signals.
Signed-off-by: Richard Genoud <richard.genoud at gmail.com>
---
.../devicetree/bindings/serial/atmel-usart.txt | 12 +-
arch/arm/mach-at91/at91rm9200_devices.c | 25 ++
arch/arm/mach-at91/at91sam9260_devices.c | 35 +++
arch/arm/mach-at91/at91sam9261_devices.c | 20 ++
arch/arm/mach-at91/at91sam9263_devices.c | 20 ++
arch/arm/mach-at91/at91sam9g45_devices.c | 25 ++
arch/arm/mach-at91/at91sam9rl_devices.c | 25 ++
drivers/tty/serial/atmel_serial.c | 290 ++++++++++++++++++---
include/linux/platform_data/atmel.h | 5 +
9 files changed, 417 insertions(+), 40 deletions(-)
diff --git a/Documentation/devicetree/bindings/serial/atmel-usart.txt b/Documentation/devicetree/bindings/serial/atmel-usart.txt
index 17c1042b2df8..77edc6504a29 100644
--- a/Documentation/devicetree/bindings/serial/atmel-usart.txt
+++ b/Documentation/devicetree/bindings/serial/atmel-usart.txt
@@ -13,8 +13,9 @@ Required properties:
Optional properties:
- atmel,use-dma-rx: use of PDC or DMA for receiving data
- atmel,use-dma-tx: use of PDC or DMA for transmitting data
-- rts-gpios: specify a GPIO for RTS line. It will use specified PIO instead of the peripheral
- function pin for the USART RTS feature. If unsure, don't specify this property.
+- {rts,cts,dtr,dsr,ri,dcd}-gpios: specify a GPIO for RTS/CTS/DTR/DSR/RI/DCD line respectively.
+ It will use specified PIO instead of the peripheral function pin for the USART feature.
+ If unsure, don't specify this property.
- add dma bindings for dma transfer:
- dmas: DMA specifier, consisting of a phandle to DMA controller node,
memory peripheral interface and USART DMA channel ID, FIFO configuration.
@@ -35,7 +36,12 @@ Example:
clock-names = "usart";
atmel,use-dma-rx;
atmel,use-dma-tx;
- rts-gpios = <&pioD 15 0>;
+ rts-gpios = <&pioD 15 GPIO_ACTIVE_LOW>;
+ cts-gpios = <&pioD 16 GPIO_ACTIVE_LOW>;
+ dtr-gpios = <&pioD 17 GPIO_ACTIVE_LOW>;
+ dsr-gpios = <&pioD 18 GPIO_ACTIVE_LOW>;
+ dcd-gpios = <&pioD 20 GPIO_ACTIVE_LOW>;
+ ri-gpios = <&pioD 19 GPIO_ACTIVE_LOW>;
};
- use DMA:
diff --git a/arch/arm/mach-at91/at91rm9200_devices.c b/arch/arm/mach-at91/at91rm9200_devices.c
index 605add05af7e..288421f38b42 100644
--- a/arch/arm/mach-at91/at91rm9200_devices.c
+++ b/arch/arm/mach-at91/at91rm9200_devices.c
@@ -923,6 +923,11 @@ static struct atmel_uart_data dbgu_data = {
.use_dma_tx = 0,
.use_dma_rx = 0, /* DBGU not capable of receive DMA */
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 dbgu_dmamask = DMA_BIT_MASK(32);
@@ -962,6 +967,11 @@ static struct atmel_uart_data uart0_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart0_dmamask = DMA_BIT_MASK(32);
@@ -1013,6 +1023,11 @@ static struct atmel_uart_data uart1_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart1_dmamask = DMA_BIT_MASK(32);
@@ -1065,6 +1080,11 @@ static struct atmel_uart_data uart2_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart2_dmamask = DMA_BIT_MASK(32);
@@ -1109,6 +1129,11 @@ static struct atmel_uart_data uart3_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart3_dmamask = DMA_BIT_MASK(32);
diff --git a/arch/arm/mach-at91/at91sam9260_devices.c b/arch/arm/mach-at91/at91sam9260_devices.c
index b52527c78b12..0e20ba04d43f 100644
--- a/arch/arm/mach-at91/at91sam9260_devices.c
+++ b/arch/arm/mach-at91/at91sam9260_devices.c
@@ -820,6 +820,11 @@ static struct atmel_uart_data dbgu_data = {
.use_dma_tx = 0,
.use_dma_rx = 0, /* DBGU not capable of receive DMA */
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 dbgu_dmamask = DMA_BIT_MASK(32);
@@ -859,6 +864,11 @@ static struct atmel_uart_data uart0_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart0_dmamask = DMA_BIT_MASK(32);
@@ -911,6 +921,11 @@ static struct atmel_uart_data uart1_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart1_dmamask = DMA_BIT_MASK(32);
@@ -955,6 +970,11 @@ static struct atmel_uart_data uart2_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart2_dmamask = DMA_BIT_MASK(32);
@@ -999,6 +1019,11 @@ static struct atmel_uart_data uart3_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart3_dmamask = DMA_BIT_MASK(32);
@@ -1043,6 +1068,11 @@ static struct atmel_uart_data uart4_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart4_dmamask = DMA_BIT_MASK(32);
@@ -1082,6 +1112,11 @@ static struct atmel_uart_data uart5_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart5_dmamask = DMA_BIT_MASK(32);
diff --git a/arch/arm/mach-at91/at91sam9261_devices.c b/arch/arm/mach-at91/at91sam9261_devices.c
index 6c1a2ecc306f..d3d7a546db9b 100644
--- a/arch/arm/mach-at91/at91sam9261_devices.c
+++ b/arch/arm/mach-at91/at91sam9261_devices.c
@@ -881,6 +881,11 @@ static struct atmel_uart_data dbgu_data = {
.use_dma_tx = 0,
.use_dma_rx = 0, /* DBGU not capable of receive DMA */
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 dbgu_dmamask = DMA_BIT_MASK(32);
@@ -920,6 +925,11 @@ static struct atmel_uart_data uart0_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart0_dmamask = DMA_BIT_MASK(32);
@@ -964,6 +974,11 @@ static struct atmel_uart_data uart1_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart1_dmamask = DMA_BIT_MASK(32);
@@ -1008,6 +1023,11 @@ static struct atmel_uart_data uart2_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart2_dmamask = DMA_BIT_MASK(32);
diff --git a/arch/arm/mach-at91/at91sam9263_devices.c b/arch/arm/mach-at91/at91sam9263_devices.c
index 97cc2a0d6f90..5fcb2a0383d1 100644
--- a/arch/arm/mach-at91/at91sam9263_devices.c
+++ b/arch/arm/mach-at91/at91sam9263_devices.c
@@ -1325,6 +1325,11 @@ static struct atmel_uart_data dbgu_data = {
.use_dma_tx = 0,
.use_dma_rx = 0, /* DBGU not capable of receive DMA */
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 dbgu_dmamask = DMA_BIT_MASK(32);
@@ -1364,6 +1369,11 @@ static struct atmel_uart_data uart0_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart0_dmamask = DMA_BIT_MASK(32);
@@ -1408,6 +1418,11 @@ static struct atmel_uart_data uart1_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart1_dmamask = DMA_BIT_MASK(32);
@@ -1452,6 +1467,11 @@ static struct atmel_uart_data uart2_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart2_dmamask = DMA_BIT_MASK(32);
diff --git a/arch/arm/mach-at91/at91sam9g45_devices.c b/arch/arm/mach-at91/at91sam9g45_devices.c
index c10149588e21..bd44970403e5 100644
--- a/arch/arm/mach-at91/at91sam9g45_devices.c
+++ b/arch/arm/mach-at91/at91sam9g45_devices.c
@@ -1588,6 +1588,11 @@ static struct atmel_uart_data dbgu_data = {
.use_dma_tx = 0,
.use_dma_rx = 0,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 dbgu_dmamask = DMA_BIT_MASK(32);
@@ -1627,6 +1632,11 @@ static struct atmel_uart_data uart0_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart0_dmamask = DMA_BIT_MASK(32);
@@ -1671,6 +1681,11 @@ static struct atmel_uart_data uart1_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart1_dmamask = DMA_BIT_MASK(32);
@@ -1715,6 +1730,11 @@ static struct atmel_uart_data uart2_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart2_dmamask = DMA_BIT_MASK(32);
@@ -1759,6 +1779,11 @@ static struct atmel_uart_data uart3_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart3_dmamask = DMA_BIT_MASK(32);
diff --git a/arch/arm/mach-at91/at91sam9rl_devices.c b/arch/arm/mach-at91/at91sam9rl_devices.c
index 4120af972b61..e43623dc1c9e 100644
--- a/arch/arm/mach-at91/at91sam9rl_devices.c
+++ b/arch/arm/mach-at91/at91sam9rl_devices.c
@@ -957,6 +957,11 @@ static struct atmel_uart_data dbgu_data = {
.use_dma_tx = 0,
.use_dma_rx = 0, /* DBGU not capable of receive DMA */
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 dbgu_dmamask = DMA_BIT_MASK(32);
@@ -996,6 +1001,11 @@ static struct atmel_uart_data uart0_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart0_dmamask = DMA_BIT_MASK(32);
@@ -1048,6 +1058,11 @@ static struct atmel_uart_data uart1_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart1_dmamask = DMA_BIT_MASK(32);
@@ -1092,6 +1107,11 @@ static struct atmel_uart_data uart2_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart2_dmamask = DMA_BIT_MASK(32);
@@ -1136,6 +1156,11 @@ static struct atmel_uart_data uart3_data = {
.use_dma_tx = 1,
.use_dma_rx = 1,
.rts_gpio = -EINVAL,
+ .cts_gpio = -EINVAL,
+ .dtr_gpio = -EINVAL,
+ .dsr_gpio = -EINVAL,
+ .ri_gpio = -EINVAL,
+ .dcd_gpio = -EINVAL,
};
static u64 uart3_dmamask = DMA_BIT_MASK(32);
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index a51b3a762948..7cb6d1954062 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -43,6 +43,8 @@
#include <linux/platform_data/atmel.h>
#include <linux/timer.h>
#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
+#include <linux/irq.h>
#include <asm/io.h>
#include <asm/ioctls.h>
@@ -57,6 +59,8 @@
#include <linux/serial_core.h>
+#include "serial_mctrl_gpio.h"
+
static void atmel_start_rx(struct uart_port *port);
static void atmel_stop_rx(struct uart_port *port);
@@ -162,8 +166,10 @@ struct atmel_uart_port {
struct circ_buf rx_ring;
struct serial_rs485 rs485; /* rs485 settings */
- int rts_gpio; /* optional RTS GPIO */
+ struct mctrl_gpios gpios;
+ int gpio_irq[UART_GPIO_MAX_INPUT];
unsigned int tx_done_mask;
+ bool ms_irq_enabled;
bool is_usart; /* usart or uart */
struct timer_list uart_timer; /* uart timer */
int (*prepare_rx)(struct uart_port *port);
@@ -237,6 +243,46 @@ static bool atmel_use_dma_rx(struct uart_port *port)
return atmel_port->use_dma_rx;
}
+static unsigned int atmel_get_lines_status(struct uart_port *port)
+{
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ unsigned int status, ret = 0;
+
+ status = UART_GET_CSR(port);
+
+ mctrl_gpio_get(&atmel_port->gpios, &ret);
+
+ if (!IS_ERR_OR_NULL(atmel_port->gpios.gpio[UART_GPIO_CTS])) {
+ if (ret & TIOCM_CTS)
+ status &= ~ATMEL_US_CTS;
+ else
+ status |= ATMEL_US_CTS;
+ }
+
+ if (!IS_ERR_OR_NULL(atmel_port->gpios.gpio[UART_GPIO_DSR])) {
+ if (ret & TIOCM_DSR)
+ status &= ~ATMEL_US_DSR;
+ else
+ status |= ATMEL_US_DSR;
+ }
+
+ if (!IS_ERR_OR_NULL(atmel_port->gpios.gpio[UART_GPIO_RI])) {
+ if (ret & TIOCM_RI)
+ status &= ~ATMEL_US_RI;
+ else
+ status |= ATMEL_US_RI;
+ }
+
+ if (!IS_ERR_OR_NULL(atmel_port->gpios.gpio[UART_GPIO_DCD])) {
+ if (ret & TIOCM_CD)
+ status &= ~ATMEL_US_DCD;
+ else
+ status |= ATMEL_US_DCD;
+ }
+
+ return status;
+}
+
/* Enable or disable the rs485 support */
void atmel_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf)
{
@@ -296,17 +342,6 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl)
unsigned int mode;
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
- /*
- * AT91RM9200 Errata #39: RTS0 is not internally connected
- * to PA21. We need to drive the pin as a GPIO.
- */
- if (gpio_is_valid(atmel_port->rts_gpio)) {
- if (mctrl & TIOCM_RTS)
- gpio_set_value(atmel_port->rts_gpio, 0);
- else
- gpio_set_value(atmel_port->rts_gpio, 1);
- }
-
if (mctrl & TIOCM_RTS)
control |= ATMEL_US_RTSEN;
else
@@ -319,6 +354,8 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl)
UART_PUT_CR(port, control);
+ mctrl_gpio_set(&atmel_port->gpios, mctrl);
+
/* Local loopback mode? */
mode = UART_GET_MR(port) & ~ATMEL_US_CHMODE;
if (mctrl & TIOCM_LOOP)
@@ -346,7 +383,8 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl)
*/
static u_int atmel_get_mctrl(struct uart_port *port)
{
- unsigned int status, ret = 0;
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ unsigned int ret = 0, status;
status = UART_GET_CSR(port);
@@ -362,7 +400,7 @@ static u_int atmel_get_mctrl(struct uart_port *port)
if (!(status & ATMEL_US_RI))
ret |= TIOCM_RI;
- return ret;
+ return mctrl_gpio_get(&atmel_port->gpios, &ret);
}
/*
@@ -449,8 +487,38 @@ static void atmel_stop_rx(struct uart_port *port)
*/
static void atmel_enable_ms(struct uart_port *port)
{
- UART_PUT_IER(port, ATMEL_US_RIIC | ATMEL_US_DSRIC
- | ATMEL_US_DCDIC | ATMEL_US_CTSIC);
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ uint32_t ier = 0;
+
+ /*
+ * Interrupt should not be enabled twice
+ */
+ if (atmel_port->ms_irq_enabled)
+ return;
+
+ atmel_port->ms_irq_enabled = true;
+
+ if (atmel_port->gpio_irq[UART_GPIO_CTS] >= 0)
+ enable_irq(atmel_port->gpio_irq[UART_GPIO_CTS]);
+ else
+ ier |= ATMEL_US_CTSIC;
+
+ if (atmel_port->gpio_irq[UART_GPIO_DSR] >= 0)
+ enable_irq(atmel_port->gpio_irq[UART_GPIO_DSR]);
+ else
+ ier |= ATMEL_US_DSRIC;
+
+ if (atmel_port->gpio_irq[UART_GPIO_RI] >= 0)
+ enable_irq(atmel_port->gpio_irq[UART_GPIO_RI]);
+ else
+ ier |= ATMEL_US_RIIC;
+
+ if (atmel_port->gpio_irq[UART_GPIO_DCD] >= 0)
+ enable_irq(atmel_port->gpio_irq[UART_GPIO_DCD]);
+ else
+ ier |= ATMEL_US_DCDIC;
+
+ UART_PUT_IER(port, ier);
}
/*
@@ -1039,11 +1107,35 @@ atmel_handle_status(struct uart_port *port, unsigned int pending,
static irqreturn_t atmel_interrupt(int irq, void *dev_id)
{
struct uart_port *port = dev_id;
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
unsigned int status, pending, pass_counter = 0;
+ bool gpio_handled = false;
do {
- status = UART_GET_CSR(port);
+ status = atmel_get_lines_status(port);
pending = status & UART_GET_IMR(port);
+ if (!gpio_handled) {
+ /*
+ * Dealing with GPIO interrupt
+ */
+ if ((irq >= 0) &&
+ (irq == atmel_port->gpio_irq[UART_GPIO_CTS]))
+ pending |= ATMEL_US_CTSIC;
+
+ if ((irq >= 0) &&
+ (irq == atmel_port->gpio_irq[UART_GPIO_DSR]))
+ pending |= ATMEL_US_DSRIC;
+
+ if ((irq >= 0) &&
+ (irq == atmel_port->gpio_irq[UART_GPIO_RI]))
+ pending |= ATMEL_US_RIIC;
+
+ if ((irq >= 0) &&
+ (irq == atmel_port->gpio_irq[UART_GPIO_DCD]))
+ pending |= ATMEL_US_DCDIC;
+
+ gpio_handled = true;
+ }
if (!pending)
break;
@@ -1523,6 +1615,45 @@ static void atmel_get_ip_name(struct uart_port *port)
}
}
+static void atmel_free_gpio_irq(struct uart_port *port)
+{
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ enum mctrl_gpio_idx i;
+
+ for (i = UART_GPIO_MIN; i < UART_GPIO_MAX_INPUT; i++)
+ if (atmel_port->gpio_irq[i] >= 0)
+ free_irq(atmel_port->gpio_irq[i], port);
+}
+
+static int atmel_request_gpio_irq(struct uart_port *port)
+{
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ int *irq = atmel_port->gpio_irq;
+ enum mctrl_gpio_idx i;
+ int err = 0;
+
+ for (i = UART_GPIO_MIN; (i < UART_GPIO_MAX_INPUT) && !err; i++) {
+ if (irq[i] < 0)
+ continue;
+
+ irq_set_status_flags(irq[i], IRQ_NOAUTOEN);
+ err = request_irq(irq[i], atmel_interrupt, IRQ_TYPE_EDGE_BOTH,
+ get_mctrl_gpio_name(i), port);
+ if (err)
+ dev_err(port->dev, "atmel_startup - Can't get %s irq\n",
+ get_mctrl_gpio_name(i));
+ }
+
+ /*
+ * If something went wrong, rollback.
+ */
+ while (err && --i)
+ if (irq[i] >= 0)
+ free_irq(irq[i], port);
+
+ return err;
+}
+
/*
* Perform initialization and enable port for reception
*/
@@ -1539,6 +1670,7 @@ static int atmel_startup(struct uart_port *port)
* handle an unexpected interrupt
*/
UART_PUT_IDR(port, -1);
+ atmel_port->ms_irq_enabled = false;
/*
* Allocate the IRQ
@@ -1551,6 +1683,13 @@ static int atmel_startup(struct uart_port *port)
}
/*
+ * Get the GPIO lines IRQ
+ */
+ retval = atmel_request_gpio_irq(port);
+ if (retval)
+ goto free_irq;
+
+ /*
* Initialize DMA (if necessary)
*/
atmel_init_property(atmel_port, pdev);
@@ -1568,7 +1707,7 @@ static int atmel_startup(struct uart_port *port)
}
/* Save current CSR for comparison in atmel_tasklet_func() */
- atmel_port->irq_status_prev = UART_GET_CSR(port);
+ atmel_port->irq_status_prev = atmel_get_lines_status(port);
atmel_port->irq_status = atmel_port->irq_status_prev;
/*
@@ -1614,6 +1753,11 @@ static int atmel_startup(struct uart_port *port)
}
return 0;
+
+free_irq:
+ free_irq(port->irq, port);
+
+ return retval;
}
/*
@@ -1661,9 +1805,12 @@ static void atmel_shutdown(struct uart_port *port)
atmel_port->rx_ring.tail = 0;
/*
- * Free the interrupt
+ * Free the interrupts
*/
free_irq(port->irq, port);
+ atmel_free_gpio_irq(port);
+
+ atmel_port->ms_irq_enabled = false;
}
/*
@@ -2327,6 +2474,86 @@ static int atmel_serial_resume(struct platform_device *pdev)
#define atmel_serial_resume NULL
#endif
+/*
+ * TODO:
+ * Suppress that stuff when the platform data is eradicated
+ */
+static int atmel_get_pdata_gpio(struct atmel_uart_port *p, struct device *dev)
+{
+ struct atmel_uart_data *pdata = dev_get_platdata(dev);
+ enum mctrl_gpio_idx i;
+ int err;
+ int ret = 0;
+
+ if (gpio_is_valid(pdata->cts_gpio))
+ p->gpios.gpio[UART_GPIO_CTS] = gpio_to_desc(pdata->cts_gpio);
+ if (gpio_is_valid(pdata->rts_gpio))
+ p->gpios.gpio[UART_GPIO_RTS] = gpio_to_desc(pdata->rts_gpio);
+ if (gpio_is_valid(pdata->dtr_gpio))
+ p->gpios.gpio[UART_GPIO_DTR] = gpio_to_desc(pdata->dtr_gpio);
+ if (gpio_is_valid(pdata->dsr_gpio))
+ p->gpios.gpio[UART_GPIO_DSR] = gpio_to_desc(pdata->dsr_gpio);
+ if (gpio_is_valid(pdata->dcd_gpio))
+ p->gpios.gpio[UART_GPIO_DCD] = gpio_to_desc(pdata->dcd_gpio);
+ if (gpio_is_valid(pdata->ri_gpio))
+ p->gpios.gpio[UART_GPIO_RI] = gpio_to_desc(pdata->ri_gpio);
+
+ for (i = UART_GPIO_MIN; i < UART_GPIO_MAX; i++) {
+ /*
+ * The GPIOs are maybe not all filled,
+ * this is not an error.
+ */
+ if (IS_ERR_OR_NULL(p->gpios.gpio[i]))
+ continue;
+
+ err = devm_gpio_request(dev, desc_to_gpio(p->gpios.gpio[i]),
+ get_mctrl_gpio_name(i));
+ if (err) {
+ dev_err(dev, "error requesting %s GPIO\n",
+ get_mctrl_gpio_name(i));
+ ret--;
+ continue;
+ }
+
+ /* Default to 1 as all signals are active low */
+ (void) gpiod_sysfs_set_active_low(p->gpios.gpio[i], 1);
+
+ if (i < UART_GPIO_MAX_INPUT)
+ err = gpiod_direction_input(p->gpios.gpio[i]);
+ else
+ err = gpiod_direction_output(p->gpios.gpio[i], 0);
+ if (err) {
+ dev_err(dev, "Unable to set direction for %s GPIO",
+ get_mctrl_gpio_name(i));
+ devm_gpio_free(dev, desc_to_gpio(p->gpios.gpio[i]));
+ p->gpios.gpio[i] = NULL;
+ ret--;
+ }
+ }
+
+ return ret;
+}
+
+static int atmel_init_gpios(struct atmel_uart_port *p, struct device *dev)
+{
+ struct atmel_uart_data *pdata = dev_get_platdata(dev);
+ enum mctrl_gpio_idx i;
+ int err;
+
+ if (pdata)
+ err = atmel_get_pdata_gpio(p, dev);
+ else
+ err = mctrl_gpio_init(dev, &p->gpios);
+
+ for (i = UART_GPIO_MIN; i < UART_GPIO_MAX_INPUT; i++)
+ if (IS_ERR_OR_NULL(p->gpios.gpio[i]))
+ p->gpio_irq[i] = -EINVAL;
+ else
+ p->gpio_irq[i] = gpiod_to_irq(p->gpios.gpio[i]);
+
+ return err;
+}
+
static int atmel_serial_probe(struct platform_device *pdev)
{
struct atmel_uart_port *port;
@@ -2362,25 +2589,11 @@ static int atmel_serial_probe(struct platform_device *pdev)
port = &atmel_ports[ret];
port->backup_imr = 0;
port->uart.line = ret;
- port->rts_gpio = -EINVAL; /* Invalid, zero could be valid */
- if (pdata)
- port->rts_gpio = pdata->rts_gpio;
- else if (np)
- port->rts_gpio = of_get_named_gpio(np, "rts-gpios", 0);
- if (gpio_is_valid(port->rts_gpio)) {
- ret = devm_gpio_request(&pdev->dev, port->rts_gpio, "RTS");
- if (ret) {
- dev_err(&pdev->dev, "error requesting RTS GPIO\n");
- goto err;
- }
- /* Default to 1 as RTS is active low */
- ret = gpio_direction_output(port->rts_gpio, 1);
- if (ret) {
- dev_err(&pdev->dev, "error setting up RTS GPIO\n");
- goto err;
- }
- }
+ ret = atmel_init_gpios(port, &pdev->dev);
+ if (ret < 0)
+ dev_err(&pdev->dev, "Failed to initialize %d GPIOs. The serial port may not work as expected",
+ ret * -1);
ret = atmel_init_port(port, pdev);
if (ret)
@@ -2434,6 +2647,7 @@ err_alloc_ring:
port->clk = NULL;
}
err:
+ mctrl_gpio_free(&port->gpios);
return ret;
}
@@ -2457,6 +2671,8 @@ static int atmel_serial_remove(struct platform_device *pdev)
clk_put(atmel_port->clk);
+ mctrl_gpio_free(&atmel_port->gpios);
+
return ret;
}
diff --git a/include/linux/platform_data/atmel.h b/include/linux/platform_data/atmel.h
index e26b0c14edea..565c5c693c7f 100644
--- a/include/linux/platform_data/atmel.h
+++ b/include/linux/platform_data/atmel.h
@@ -85,6 +85,11 @@ struct atmel_uart_data {
void __iomem *regs; /* virt. base address, if any */
struct serial_rs485 rs485; /* rs485 settings */
int rts_gpio; /* optional RTS GPIO */
+ int cts_gpio; /* optional CTS GPIO */
+ int dtr_gpio; /* optional DTR GPIO */
+ int dsr_gpio; /* optional DSR GPIO */
+ int dcd_gpio; /* optional DCD GPIO */
+ int ri_gpio; /* optional Ring GPIO */
};
/* Touchscreen Controller */
--
1.8.5
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