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authorQipan Li <Qipan.Li@csr.com>2013-08-15 06:52:15 +0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-08-14 18:33:08 -0700
commit2eb5618de87927e540055edc625b22f2d5662ab5 (patch)
tree87852ae0db68a69b7eab5fcfc43693d0a9df40c9 /drivers/tty
parenta343756e07884e4cecd3a4297de7f121e5bb8829 (diff)
serial: sirf: fix the hardware-flow-ctrl for USP-based UART
for USP-based UART, we use two gpios as RTS and CST pins. Signed-off-by: Qipan Li <Qipan.Li@csr.com> Signed-off-by: Barry Song <Baohua.Song@csr.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
-rw-r--r--drivers/tty/serial/sirfsoc_uart.c161
-rw-r--r--drivers/tty/serial/sirfsoc_uart.h6
2 files changed, 122 insertions, 45 deletions
diff --git a/drivers/tty/serial/sirfsoc_uart.c b/drivers/tty/serial/sirfsoc_uart.c
index d87003d49c0..ed3b8904627 100644
--- a/drivers/tty/serial/sirfsoc_uart.c
+++ b/drivers/tty/serial/sirfsoc_uart.c
@@ -20,6 +20,7 @@
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/io.h>
+#include <linux/of_gpio.h>
#include <asm/irq.h>
#include <asm/mach/irq.h>
@@ -110,14 +111,19 @@ static unsigned int sirfsoc_uart_get_mctrl(struct uart_port *port)
{
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
- if (!(sirfport->ms_enabled)) {
+ if (!sirfport->hw_flow_ctrl || !sirfport->ms_enabled)
goto cts_asserted;
- } else if (sirfport->hw_flow_ctrl) {
+ if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
if (!(rd_regl(port, ureg->sirfsoc_afc_ctrl) &
SIRFUART_AFC_CTS_STATUS))
goto cts_asserted;
else
goto cts_deasserted;
+ } else {
+ if (!gpio_get_value(sirfport->cts_gpio))
+ goto cts_asserted;
+ else
+ goto cts_deasserted;
}
cts_deasserted:
return TIOCM_CAR | TIOCM_DSR;
@@ -132,10 +138,18 @@ static void sirfsoc_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
unsigned int assert = mctrl & TIOCM_RTS;
unsigned int val = assert ? SIRFUART_AFC_CTRL_RX_THD : 0x0;
unsigned int current_val;
- if (sirfport->hw_flow_ctrl) {
+
+ if (!sirfport->hw_flow_ctrl || !sirfport->ms_enabled)
+ return;
+ if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
current_val = rd_regl(port, ureg->sirfsoc_afc_ctrl) & ~0xFF;
val |= current_val;
wr_regl(port, ureg->sirfsoc_afc_ctrl, val);
+ } else {
+ if (!val)
+ gpio_set_value(sirfport->rts_gpio, 1);
+ else
+ gpio_set_value(sirfport->rts_gpio, 0);
}
}
@@ -195,21 +209,32 @@ static void sirfsoc_uart_disable_ms(struct uart_port *port)
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
- unsigned long reg;
- sirfport->ms_enabled = 0;
if (!sirfport->hw_flow_ctrl)
return;
-
- reg = rd_regl(port, ureg->sirfsoc_afc_ctrl);
- wr_regl(port, ureg->sirfsoc_afc_ctrl, reg & ~0x3FF);
- if (!sirfport->is_marco) {
- reg = rd_regl(port, ureg->sirfsoc_int_en_reg);
- wr_regl(port, ureg->sirfsoc_int_en_reg,
- reg & ~uint_en->sirfsoc_cts_en);
+ sirfport->ms_enabled = false;
+ if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
+ wr_regl(port, ureg->sirfsoc_afc_ctrl,
+ rd_regl(port, ureg->sirfsoc_afc_ctrl) & ~0x3FF);
+ if (!sirfport->is_marco)
+ wr_regl(port, ureg->sirfsoc_int_en_reg,
+ rd_regl(port, ureg->sirfsoc_int_en_reg)&
+ ~uint_en->sirfsoc_cts_en);
+ else
+ wr_regl(port, SIRFUART_INT_EN_CLR,
+ uint_en->sirfsoc_cts_en);
} else
- wr_regl(port, SIRFUART_INT_EN_CLR,
- uint_en->sirfsoc_cts_en);
+ disable_irq(gpio_to_irq(sirfport->cts_gpio));
+}
+
+static irqreturn_t sirfsoc_uart_usp_cts_handler(int irq, void *dev_id)
+{
+ struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)dev_id;
+ struct uart_port *port = &sirfport->port;
+ if (gpio_is_valid(sirfport->cts_gpio) && sirfport->ms_enabled)
+ uart_handle_cts_change(port,
+ !gpio_get_value(sirfport->cts_gpio));
+ return IRQ_HANDLED;
}
static void sirfsoc_uart_enable_ms(struct uart_port *port)
@@ -217,25 +242,23 @@ static void sirfsoc_uart_enable_ms(struct uart_port *port)
struct sirfsoc_uart_port *sirfport = to_sirfport(port);
struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
- unsigned long reg;
- unsigned long flg;
if (!sirfport->hw_flow_ctrl)
return;
- flg = SIRFUART_AFC_TX_EN | SIRFUART_AFC_RX_EN;
- reg = rd_regl(port, ureg->sirfsoc_afc_ctrl);
- wr_regl(port, ureg->sirfsoc_afc_ctrl, reg | flg);
- if (!sirfport->is_marco) {
- reg = rd_regl(port, ureg->sirfsoc_int_en_reg);
- wr_regl(port, ureg->sirfsoc_int_en_reg,
- reg | uint_en->sirfsoc_cts_en);
+ sirfport->ms_enabled = true;
+ if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
+ wr_regl(port, ureg->sirfsoc_afc_ctrl,
+ rd_regl(port, ureg->sirfsoc_afc_ctrl) |
+ SIRFUART_AFC_TX_EN | SIRFUART_AFC_RX_EN);
+ if (!sirfport->is_marco)
+ wr_regl(port, ureg->sirfsoc_int_en_reg,
+ rd_regl(port, ureg->sirfsoc_int_en_reg)
+ | uint_en->sirfsoc_cts_en);
+ else
+ wr_regl(port, ureg->sirfsoc_int_en_reg,
+ uint_en->sirfsoc_cts_en);
} else
- wr_regl(port, ureg->sirfsoc_int_en_reg,
- uint_en->sirfsoc_cts_en);
- uart_handle_cts_change(port,
- !(rd_regl(port, ureg->sirfsoc_afc_ctrl) &
- SIRFUART_AFC_CTS_STATUS));
- sirfport->ms_enabled = 1;
+ enable_irq(gpio_to_irq(sirfport->cts_gpio));
}
static void sirfsoc_uart_break_ctl(struct uart_port *port, int break_state)
@@ -505,8 +528,7 @@ static void sirfsoc_uart_set_termios(struct uart_port *port,
if (termios->c_iflag & INPCK)
port->read_status_mask |= uint_en->sirfsoc_frm_err_en |
uint_en->sirfsoc_parity_err_en;
- }
- if (sirfport->uart_reg->uart_type == SIRF_USP_UART) {
+ } else {
if (termios->c_iflag & INPCK)
port->read_status_mask |= uint_en->sirfsoc_frm_err_en;
}
@@ -529,8 +551,7 @@ static void sirfsoc_uart_set_termios(struct uart_port *port,
config_reg |= SIRFUART_STICK_BIT_EVEN;
}
}
- }
- if (sirfport->uart_reg->uart_type == SIRF_USP_UART) {
+ } else {
if (termios->c_iflag & IGNPAR)
port->ignore_status_mask |=
uint_en->sirfsoc_frm_err_en;
@@ -567,8 +588,7 @@ static void sirfsoc_uart_set_termios(struct uart_port *port,
clk_div_reg = sirfsoc_uart_calc_sample_div(baud_rate,
ioclk_rate, &set_baud);
wr_regl(port, ureg->sirfsoc_divisor, clk_div_reg);
- }
- if (sirfport->uart_reg->uart_type == SIRF_USP_UART) {
+ } else {
clk_div_reg = sirfsoc_usp_calc_sample_div(baud_rate,
ioclk_rate, &sample_div_reg);
sample_div_reg--;
@@ -593,8 +613,7 @@ static void sirfsoc_uart_set_termios(struct uart_port *port,
if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
config_reg |= SIRFUART_RECV_TIMEOUT(port, rx_time_out);
wr_regl(port, ureg->sirfsoc_line_ctrl, config_reg);
- }
- if (sirfport->uart_reg->uart_type == SIRF_USP_UART) {
+ } else {
/*tx frame ctrl*/
len_val = (data_bit_len - 1) << 0;
len_val |= (data_bit_len + 1 + stop_bit_len - 1) << 16;
@@ -675,7 +694,25 @@ static int sirfsoc_uart_startup(struct uart_port *port)
goto irq_err;
}
startup_uart_controller(port);
+
+ sirfport->ms_enabled = false;
+ if (sirfport->uart_reg->uart_type == SIRF_USP_UART &&
+ sirfport->hw_flow_ctrl) {
+ set_irq_flags(gpio_to_irq(sirfport->cts_gpio),
+ IRQF_VALID | IRQF_NOAUTOEN);
+ ret = request_irq(gpio_to_irq(sirfport->cts_gpio),
+ sirfsoc_uart_usp_cts_handler, IRQF_TRIGGER_FALLING |
+ IRQF_TRIGGER_RISING, "usp_cts_irq", sirfport);
+ if (ret != 0) {
+ dev_err(port->dev, "UART-USP:request gpio irq fail\n");
+ goto init_rx_err;
+ }
+ }
+
enable_irq(port->irq);
+
+init_rx_err:
+ free_irq(port->irq, sirfport);
irq_err:
return ret;
}
@@ -690,9 +727,12 @@ static void sirfsoc_uart_shutdown(struct uart_port *port)
wr_regl(port, SIRFUART_INT_EN_CLR, ~0UL);
free_irq(port->irq, sirfport);
- if (sirfport->ms_enabled) {
+ if (sirfport->ms_enabled)
sirfsoc_uart_disable_ms(port);
- sirfport->ms_enabled = 0;
+ if (sirfport->uart_reg->uart_type == SIRF_USP_UART &&
+ sirfport->hw_flow_ctrl) {
+ gpio_set_value(sirfport->rts_gpio, 1);
+ free_irq(gpio_to_irq(sirfport->cts_gpio), sirfport);
}
}
@@ -852,16 +892,51 @@ static int sirfsoc_uart_probe(struct platform_device *pdev)
port->private_data = sirfport;
sirfport->uart_reg = (struct sirfsoc_uart_register *)match->data;
+ sirfport->hw_flow_ctrl = of_property_read_bool(pdev->dev.of_node,
+ "sirf,uart-has-rtscts");
if (of_device_is_compatible(pdev->dev.of_node, "sirf,prima2-uart"))
sirfport->uart_reg->uart_type = SIRF_REAL_UART;
- if (of_device_is_compatible(pdev->dev.of_node, "sirf,prima2-usp-uart"))
+ if (of_device_is_compatible(pdev->dev.of_node, "sirf,prima2-usp-uart")) {
sirfport->uart_reg->uart_type = SIRF_USP_UART;
+ if (!sirfport->hw_flow_ctrl)
+ goto usp_no_flow_control;
+ if (of_find_property(pdev->dev.of_node, "cts-gpios", NULL))
+ sirfport->cts_gpio = of_get_named_gpio(
+ pdev->dev.of_node, "cts-gpios", 0);
+ else
+ sirfport->cts_gpio = -1;
+ if (of_find_property(pdev->dev.of_node, "rts-gpios", NULL))
+ sirfport->rts_gpio = of_get_named_gpio(
+ pdev->dev.of_node, "rts-gpios", 0);
+ else
+ sirfport->rts_gpio = -1;
+
+ if ((!gpio_is_valid(sirfport->cts_gpio) ||
+ !gpio_is_valid(sirfport->rts_gpio))) {
+ ret = -EINVAL;
+ dev_err(&pdev->dev,
+ "Usp flow control must have rfs and tfs gpio");
+ goto err;
+ }
+ ret = devm_gpio_request(&pdev->dev, sirfport->cts_gpio,
+ "usp-rfs-gpio");
+ if (ret) {
+ dev_err(&pdev->dev, "Unable request rfs gpio");
+ goto err;
+ }
+ gpio_direction_input(sirfport->cts_gpio);
+ ret = devm_gpio_request(&pdev->dev, sirfport->rts_gpio,
+ "usp-tfs-gpio");
+ if (ret) {
+ dev_err(&pdev->dev, "Unable request tfs gpio");
+ goto err;
+ }
+ gpio_direction_output(sirfport->rts_gpio, 1);
+ }
+usp_no_flow_control:
if (of_device_is_compatible(pdev->dev.of_node, "sirf,marco-uart"))
sirfport->is_marco = true;
- if (of_find_property(pdev->dev.of_node, "hw_flow_ctrl", NULL))
- sirfport->hw_flow_ctrl = 1;
-
if (of_property_read_u32(pdev->dev.of_node,
"fifosize",
&port->fifosize)) {
diff --git a/drivers/tty/serial/sirfsoc_uart.h b/drivers/tty/serial/sirfsoc_uart.h
index 2b41b06362d..e87035a9bbc 100644
--- a/drivers/tty/serial/sirfsoc_uart.h
+++ b/drivers/tty/serial/sirfsoc_uart.h
@@ -363,14 +363,16 @@ struct sirfsoc_baudrate_to_regv {
};
struct sirfsoc_uart_port {
- unsigned char hw_flow_ctrl;
- unsigned char ms_enabled;
+ bool hw_flow_ctrl;
+ bool ms_enabled;
struct uart_port port;
struct clk *clk;
/* for SiRFmarco, there are SET/CLR for UART_INT_EN */
bool is_marco;
struct sirfsoc_uart_register *uart_reg;
+ unsigned int cts_gpio;
+ unsigned int rts_gpio;
};
/* Hardware Flow Control */