Commit 2eb5618d authored by Qipan Li's avatar Qipan Li Committed by Greg Kroah-Hartman
Browse files

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: default avatarQipan Li <Qipan.Li@csr.com>
Signed-off-by: default avatarBarry Song <Baohua.Song@csr.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent a343756e

drivers/tty/serial/sirfsoc_uart.c

+118 −43
Original line number Diff line number Diff line
@@ -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);

	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,

			reg & ~uint_en->sirfsoc_cts_en);

	} else

					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

		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);

	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,

				reg | uint_en->sirfsoc_cts_en);

	} else

					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);

	uart_handle_cts_change(port,

		!(rd_regl(port, ureg->sirfsoc_afc_ctrl) &

				SIRFUART_AFC_CTS_STATUS));

	sirfport->ms_enabled = 1;

	} else

		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)) {

drivers/tty/serial/sirfsoc_uart.h

+4 −2
Original line number Diff line number Diff line
@@ -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 */