[PATCH 04/18] Blackfin Serial Driver: Change hardware flowcontrol from poll to interrupt driven.

Bryan Wu
2009-03-06T06:42:23Z

From: Sonic Zhang <sonic.zhang@analog.com>

Only CTS bit is affected.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
---
.../mach-bf527/include/mach/bfin_serial_5xx.h | 26 ----
.../mach-bf533/include/mach/bfin_serial_5xx.h | 20 ---
.../mach-bf537/include/mach/bfin_serial_5xx.h | 27 ----
.../mach-bf548/include/mach/bfin_serial_5xx.h | 45 -------
.../mach-bf561/include/mach/bfin_serial_5xx.h | 20 ---
drivers/serial/bfin_5xx.c | 131 ++++++++++++--------
6 files changed, 82 insertions(+), 187 deletions(-)

diff --git a/arch/blackfin/mach-bf527/include/mach/bfin_serial_5xx.h b/arch/blackfin/mach-bf527/include/mach/bfin_serial_5xx.h
index e8c41fd..d2b160c 100644
--- a/arch/blackfin/mach-bf527/include/mach/bfin_serial_5xx.h
+++ b/arch/blackfin/mach-bf527/include/mach/bfin_serial_5xx.h
@@ -167,29 +167,3 @@ struct bfin_serial_res bfin_serial_resource[] = {
};

#define DRIVER_NAME "bfin-uart"
-
-static void bfin_serial_hw_init(struct bfin_serial_port *uart)
-{
-
-#ifdef CONFIG_SERIAL_BFIN_UART0
- peripheral_request(P_UART0_TX, DRIVER_NAME);
- peripheral_request(P_UART0_RX, DRIVER_NAME);
-#endif
-
-#ifdef CONFIG_SERIAL_BFIN_UART1
- peripheral_request(P_UART1_TX, DRIVER_NAME);
- peripheral_request(P_UART1_RX, DRIVER_NAME);
-#endif
-
-#ifdef CONFIG_SERIAL_BFIN_CTSRTS
- if (uart->cts_pin >= 0) {
- gpio_request(uart->cts_pin, DRIVER_NAME);
- gpio_direction_input(uart->cts_pin);
- }
-
- if (uart->rts_pin >= 0) {
- gpio_request(uart->rts_pin, DRIVER_NAME);
- gpio_direction_output(uart->rts_pin, 0);
- }
-#endif
-}
diff --git a/arch/blackfin/mach-bf533/include/mach/bfin_serial_5xx.h b/arch/blackfin/mach-bf533/include/mach/bfin_serial_5xx.h
index 5f517f5..70356dd 100644
--- a/arch/blackfin/mach-bf533/include/mach/bfin_serial_5xx.h
+++ b/arch/blackfin/mach-bf533/include/mach/bfin_serial_5xx.h
@@ -142,23 +142,3 @@ struct bfin_serial_res bfin_serial_resource[] = {
};

#define DRIVER_NAME "bfin-uart"
-
-static void bfin_serial_hw_init(struct bfin_serial_port *uart)
-{
-
-#ifdef CONFIG_SERIAL_BFIN_UART0
- peripheral_request(P_UART0_TX, DRIVER_NAME);
- peripheral_request(P_UART0_RX, DRIVER_NAME);
-#endif
-
-#ifdef CONFIG_SERIAL_BFIN_CTSRTS
- if (uart->cts_pin >= 0) {
- gpio_request(uart->cts_pin, DRIVER_NAME);
- gpio_direction_input(uart->cts_pin);
- }
- if (uart->rts_pin >= 0) {
- gpio_request(uart->rts_pin, DRIVER_NAME);
- gpio_direction_output(uart->rts_pin, 0);
- }
-#endif
-}
diff --git a/arch/blackfin/mach-bf537/include/mach/bfin_serial_5xx.h b/arch/blackfin/mach-bf537/include/mach/bfin_serial_5xx.h
index 9e34700..d46fc4f 100644
--- a/arch/blackfin/mach-bf537/include/mach/bfin_serial_5xx.h
+++ b/arch/blackfin/mach-bf537/include/mach/bfin_serial_5xx.h
@@ -99,7 +99,6 @@ struct bfin_serial_port {
struct work_struct tx_dma_workqueue;
#endif
#ifdef CONFIG_SERIAL_BFIN_CTSRTS
- struct timer_list cts_timer;
int cts_pin;
int rts_pin;
#endif
@@ -167,29 +166,3 @@ struct bfin_serial_res bfin_serial_resource[] = {
};

#define DRIVER_NAME "bfin-uart"
-
-static void bfin_serial_hw_init(struct bfin_serial_port *uart)
-{
-
-#ifdef CONFIG_SERIAL_BFIN_UART0
- peripheral_request(P_UART0_TX, DRIVER_NAME);
- peripheral_request(P_UART0_RX, DRIVER_NAME);
-#endif
-
-#ifdef CONFIG_SERIAL_BFIN_UART1
- peripheral_request(P_UART1_TX, DRIVER_NAME);
- peripheral_request(P_UART1_RX, DRIVER_NAME);
-#endif
-
-#ifdef CONFIG_SERIAL_BFIN_CTSRTS
- if (uart->cts_pin >= 0) {
- gpio_request(uart->cts_pin, DRIVER_NAME);
- gpio_direction_input(uart->cts_pin);
- }
-
- if (uart->rts_pin >= 0) {
- gpio_request(uart->rts_pin, DRIVER_NAME);
- gpio_direction_output(uart->rts_pin, 0);
- }
-#endif
-}
diff --git a/arch/blackfin/mach-bf548/include/mach/bfin_serial_5xx.h b/arch/blackfin/mach-bf548/include/mach/bfin_serial_5xx.h
index c05e79c..388e232 100644
--- a/arch/blackfin/mach-bf548/include/mach/bfin_serial_5xx.h
+++ b/arch/blackfin/mach-bf548/include/mach/bfin_serial_5xx.h
@@ -181,48 +181,3 @@ struct bfin_serial_res bfin_serial_resource[] = {
};

#define DRIVER_NAME "bfin-uart"
-
-static void bfin_serial_hw_init(struct bfin_serial_port *uart)
-{
-#ifdef CONFIG_SERIAL_BFIN_UART0
- peripheral_request(P_UART0_TX, DRIVER_NAME);
- peripheral_request(P_UART0_RX, DRIVER_NAME);
-#endif
-
-#ifdef CONFIG_SERIAL_BFIN_UART1
- peripheral_request(P_UART1_TX, DRIVER_NAME);
- peripheral_request(P_UART1_RX, DRIVER_NAME);
-
-#ifdef CONFIG_BFIN_UART1_CTSRTS
- peripheral_request(P_UART1_RTS, DRIVER_NAME);
- peripheral_request(P_UART1_CTS, DRIVER_NAME);
-#endif
-#endif
-
-#ifdef CONFIG_SERIAL_BFIN_UART2
- peripheral_request(P_UART2_TX, DRIVER_NAME);
- peripheral_request(P_UART2_RX, DRIVER_NAME);
-#endif
-
-#ifdef CONFIG_SERIAL_BFIN_UART3
- peripheral_request(P_UART3_TX, DRIVER_NAME);
- peripheral_request(P_UART3_RX, DRIVER_NAME);
-
-#ifdef CONFIG_BFIN_UART3_CTSRTS
- peripheral_request(P_UART3_RTS, DRIVER_NAME);
- peripheral_request(P_UART3_CTS, DRIVER_NAME);
-#endif
-#endif
- SSYNC();
-#ifdef CONFIG_SERIAL_BFIN_CTSRTS
- if (uart->cts_pin >= 0) {
- gpio_request(uart->cts_pin, DRIVER_NAME);
- gpio_direction_input(uart->cts_pin);
- }
-
- if (uart->rts_pin >= 0) {
- gpio_request(uart->rts_pin, DRIVER_NAME);
- gpio_direction_output(uart->rts_pin, 0);
- }
-#endif
-}
diff --git a/arch/blackfin/mach-bf561/include/mach/bfin_serial_5xx.h b/arch/blackfin/mach-bf561/include/mach/bfin_serial_5xx.h
index ca8c5f6..d0469e3 100644
--- a/arch/blackfin/mach-bf561/include/mach/bfin_serial_5xx.h
+++ b/arch/blackfin/mach-bf561/include/mach/bfin_serial_5xx.h
@@ -142,23 +142,3 @@ struct bfin_serial_res bfin_serial_resource[] = {
};

#define DRIVER_NAME "bfin-uart"
-
-static void bfin_serial_hw_init(struct bfin_serial_port *uart)
-{
-
-#ifdef CONFIG_SERIAL_BFIN_UART0
- peripheral_request(P_UART0_TX, DRIVER_NAME);
- peripheral_request(P_UART0_RX, DRIVER_NAME);
-#endif
-
-#ifdef CONFIG_SERIAL_BFIN_CTSRTS
- if (uart->cts_pin >= 0) {
- gpio_request(uart->cts_pin, DRIVER_NAME);
- gpio_direction_input(uart->cts_pin);
- }
- if (uart->rts_pin >= 0) {
- gpio_request(uart->rts_pin, DRIVER_NAME);
- gpio_direction_output(uart->rts_pin, 0);
- }
-#endif
-}
diff --git a/drivers/serial/bfin_5xx.c b/drivers/serial/bfin_5xx.c
index 1e027e3..8d34ccd 100644
--- a/drivers/serial/bfin_5xx.c
+++ b/drivers/serial/bfin_5xx.c
@@ -64,7 +64,6 @@ static int kgdboc_break_enabled;
#define DMA_RX_YCOUNT (PAGE_SIZE / DMA_RX_XCOUNT)

#define DMA_RX_FLUSH_JIFFIES (HZ / 50)
-#define CTS_CHECK_JIFFIES (HZ / 50)

#ifdef CONFIG_SERIAL_BFIN_DMA
static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart);
@@ -72,8 +71,6 @@ static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart);
static void bfin_serial_tx_chars(struct bfin_serial_port *uart);
#endif

-static void bfin_serial_mctrl_check(struct bfin_serial_port *uart);
-
static void bfin_serial_reset_irda(struct uart_port *port);

/*
@@ -265,12 +262,6 @@ static void bfin_serial_tx_chars(struct bfin_serial_port *uart)
{
struct circ_buf *xmit = &uart->port.info->xmit;

- /*
- * Check the modem control lines before
- * transmitting anything.
- */
- bfin_serial_mctrl_check(uart);
-
if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
#ifdef CONFIG_BF54x
/* Clear TFI bit */
@@ -329,12 +320,6 @@ static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)

uart->tx_done = 0;

- /*
- * Check the modem control lines before
- * transmitting anything.
- */
- bfin_serial_mctrl_check(uart);
-
if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
uart->tx_count = 0;
uart->tx_done = 1;
@@ -524,29 +509,21 @@ static void bfin_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
#endif
}

+#ifdef CONFIG_SERIAL_BFIN_CTSRTS
/*
- * Handle any change of modem status signal since we were last called.
+ * Handle any change of modem status signal.
*/
-static void bfin_serial_mctrl_check(struct bfin_serial_port *uart)
+static irqreturn_t bfin_serial_mctrl_cts_int(int irq, void *dev_id)
{
-#ifdef CONFIG_SERIAL_BFIN_CTSRTS
+ struct bfin_serial_port *uart = dev_id;
unsigned int status;
- struct uart_info *info = uart->port.info;
- struct tty_struct *tty = info->port.tty;

status = bfin_serial_get_mctrl(&uart->port);
uart_handle_cts_change(&uart->port, status & TIOCM_CTS);
- if (!(status & TIOCM_CTS)) {
- tty->hw_stopped = 1;
- uart->cts_timer.data = (unsigned long)(uart);
- uart->cts_timer.function = (void *)bfin_serial_mctrl_check;
- uart->cts_timer.expires = jiffies + CTS_CHECK_JIFFIES;
- add_timer(&(uart->cts_timer));
- } else {
- tty->hw_stopped = 0;
- }
-#endif
+
+ return IRQ_HANDLED;
}
+#endif

/*
* Interrupts are always disabled.
@@ -606,7 +583,7 @@ static int bfin_serial_startup(struct uart_port *port)
uart->rx_dma_timer.expires = jiffies + DMA_RX_FLUSH_JIFFIES;
add_timer(&(uart->rx_dma_timer));
#else
-#if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
+# if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
if (kgdboc_port_line == uart->port.line && kgdboc_break_enabled)
kgdboc_break_enabled = 0;
@@ -661,11 +638,28 @@ static int bfin_serial_startup(struct uart_port *port)
}
}
# endif
-#if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
+# if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
}
# endif
#endif
+
+#ifdef CONFIG_SERIAL_BFIN_CTSRTS
+ if (uart->cts_pin >= 0) {
+ if (request_irq(gpio_to_irq(uart->cts_pin),
+ bfin_serial_mctrl_cts_int,
+ IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
+ IRQF_DISABLED, "BFIN_UART_CTS", uart)) {
+ uart->cts_pin = -1;
+ pr_info("Unable to attach BlackFin UART CTS interrupt.\
+ So, disable it.\n");
+ }
+ }
+ if (uart->rts_pin >= 0) {
+ gpio_request(uart->rts_pin, DRIVER_NAME);
+ gpio_direction_output(uart->rts_pin, 0);
+ }
+#endif
UART_SET_IER(uart, ERBFI);
return 0;
}
@@ -699,6 +693,13 @@ static void bfin_serial_shutdown(struct uart_port *port)
free_irq(uart->port.irq, uart);
free_irq(uart->port.irq+1, uart);
#endif
+
+# ifdef CONFIG_SERIAL_BFIN_CTSRTS
+ if (uart->cts_pin >= 0)
+ free_irq(gpio_to_irq(uart->cts_pin), uart);
+ if (uart->rts_pin >= 0)
+ gpio_free(uart->rts_pin);
+# endif
}

static void
@@ -864,6 +865,20 @@ static void bfin_serial_set_ldisc(struct uart_port *port)
}
}

+static void bfin_serial_reset_irda(struct uart_port *port)
+{
+ int line = port->line;
+ unsigned short val;
+
+ val = UART_GET_GCTL(&bfin_serial_ports[line]);
+ val &= ~(IREN | RPOLC);
+ UART_PUT_GCTL(&bfin_serial_ports[line], val);
+ SSYNC();
+ val |= (IREN | RPOLC);
+ UART_PUT_GCTL(&bfin_serial_ports[line], val);
+ SSYNC();
+}
+
#ifdef CONFIG_CONSOLE_POLL
static void bfin_serial_poll_put_char(struct uart_port *port, unsigned char chr)
{
@@ -909,20 +924,6 @@ static int bfin_kgdboc_port_startup(struct uart_port *port)
}
#endif

-static void bfin_serial_reset_irda(struct uart_port *port)
-{
- int line = port->line;
- unsigned short val;
-
- val = UART_GET_GCTL(&bfin_serial_ports[line]);
- val &= ~(IREN | RPOLC);
- UART_PUT_GCTL(&bfin_serial_ports[line], val);
- SSYNC();
- val |= (IREN | RPOLC);
- UART_PUT_GCTL(&bfin_serial_ports[line], val);
- SSYNC();
-}
-
static struct uart_ops bfin_serial_pops = {
.tx_empty = bfin_serial_tx_empty,
.set_mctrl = bfin_serial_set_mctrl,
@@ -952,6 +953,39 @@ static struct uart_ops bfin_serial_pops = {
#endif
};

+static void __init bfin_serial_hw_init(void)
+{
+#ifdef CONFIG_SERIAL_BFIN_UART0
+ peripheral_request(P_UART0_TX, DRIVER_NAME);
+ peripheral_request(P_UART0_RX, DRIVER_NAME);
+#endif
+
+#ifdef CONFIG_SERIAL_BFIN_UART1
+ peripheral_request(P_UART1_TX, DRIVER_NAME);
+ peripheral_request(P_UART1_RX, DRIVER_NAME);
+
+# if defined(CONFIG_BFIN_UART1_CTSRTS) && defined(CONFIG_BF54x)
+ peripheral_request(P_UART1_RTS, DRIVER_NAME);
+ peripheral_request(P_UART1_CTS, DRIVER_NAME);
+# endif
+#endif
+
+#ifdef CONFIG_SERIAL_BFIN_UART2
+ peripheral_request(P_UART2_TX, DRIVER_NAME);
+ peripheral_request(P_UART2_RX, DRIVER_NAME);
+#endif
+
+#ifdef CONFIG_SERIAL_BFIN_UART3
+ peripheral_request(P_UART3_TX, DRIVER_NAME);
+ peripheral_request(P_UART3_RX, DRIVER_NAME);
+
+# if defined(CONFIG_BFIN_UART3_CTSRTS) && defined(CONFIG_BF54x)
+ peripheral_request(P_UART3_RTS, DRIVER_NAME);
+ peripheral_request(P_UART3_CTS, DRIVER_NAME);
+# endif
+#endif
+}
+
static void __init bfin_serial_init_ports(void)
{
static int first = 1;
@@ -961,6 +995,8 @@ static void __init bfin_serial_init_ports(void)
return;
first = 0;

+ bfin_serial_hw_init();
+
for (i = 0; i < nr_active_ports; i++) {
bfin_serial_ports[i].port.uartclk = get_sclk();
bfin_serial_ports[i].port.fifosize = BFIN_UART_TX_FIFO_SIZE;
@@ -984,15 +1020,12 @@ static void __init bfin_serial_init_ports(void)
init_timer(&(bfin_serial_ports[i].rx_dma_timer));
#endif
#ifdef CONFIG_SERIAL_BFIN_CTSRTS
- init_timer(&(bfin_serial_ports[i].cts_timer));
bfin_serial_ports[i].cts_pin =
bfin_serial_resource[i].uart_cts_pin;
bfin_serial_ports[i].rts_pin =
bfin_serial_resource[i].uart_rts_pin;
#endif
- bfin_serial_hw_init(&bfin_serial_ports[i]);
}
-
}

#if defined(CONFIG_SERIAL_BFIN_CONSOLE) || defined(CONFIG_EARLY_PRINTK)
--
1.5.6.3