793 lines
		
	
	
		
			18 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			793 lines
		
	
	
		
			18 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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| /*
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|  * Copyright (C) 2012-2015 Spreadtrum Communications Inc.
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|  */
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| 
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| #if defined(CONFIG_SERIAL_SPRD_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
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| #define SUPPORT_SYSRQ
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| #endif
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| 
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| #include <linux/clk.h>
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| #include <linux/console.h>
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| #include <linux/delay.h>
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| #include <linux/io.h>
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| #include <linux/ioport.h>
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| #include <linux/kernel.h>
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| #include <linux/module.h>
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| #include <linux/of.h>
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| #include <linux/platform_device.h>
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| #include <linux/serial_core.h>
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| #include <linux/serial.h>
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| #include <linux/slab.h>
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| #include <linux/tty.h>
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| #include <linux/tty_flip.h>
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| 
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| /* device name */
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| #define UART_NR_MAX		8
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| #define SPRD_TTY_NAME		"ttyS"
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| #define SPRD_FIFO_SIZE		128
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| #define SPRD_DEF_RATE		26000000
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| #define SPRD_BAUD_IO_LIMIT	3000000
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| #define SPRD_TIMEOUT		256000
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| 
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| /* the offset of serial registers and BITs for them */
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| /* data registers */
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| #define SPRD_TXD		0x0000
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| #define SPRD_RXD		0x0004
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| 
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| /* line status register and its BITs  */
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| #define SPRD_LSR		0x0008
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| #define SPRD_LSR_OE		BIT(4)
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| #define SPRD_LSR_FE		BIT(3)
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| #define SPRD_LSR_PE		BIT(2)
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| #define SPRD_LSR_BI		BIT(7)
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| #define SPRD_LSR_TX_OVER	BIT(15)
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| 
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| /* data number in TX and RX fifo */
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| #define SPRD_STS1		0x000C
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| 
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| /* interrupt enable register and its BITs */
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| #define SPRD_IEN		0x0010
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| #define SPRD_IEN_RX_FULL	BIT(0)
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| #define SPRD_IEN_TX_EMPTY	BIT(1)
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| #define SPRD_IEN_BREAK_DETECT	BIT(7)
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| #define SPRD_IEN_TIMEOUT	BIT(13)
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| 
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| /* interrupt clear register */
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| #define SPRD_ICLR		0x0014
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| #define SPRD_ICLR_TIMEOUT	BIT(13)
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| 
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| /* line control register */
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| #define SPRD_LCR		0x0018
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| #define SPRD_LCR_STOP_1BIT	0x10
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| #define SPRD_LCR_STOP_2BIT	0x30
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| #define SPRD_LCR_DATA_LEN	(BIT(2) | BIT(3))
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| #define SPRD_LCR_DATA_LEN5	0x0
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| #define SPRD_LCR_DATA_LEN6	0x4
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| #define SPRD_LCR_DATA_LEN7	0x8
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| #define SPRD_LCR_DATA_LEN8	0xc
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| #define SPRD_LCR_PARITY	(BIT(0) | BIT(1))
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| #define SPRD_LCR_PARITY_EN	0x2
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| #define SPRD_LCR_EVEN_PAR	0x0
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| #define SPRD_LCR_ODD_PAR	0x1
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| 
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| /* control register 1 */
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| #define SPRD_CTL1			0x001C
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| #define RX_HW_FLOW_CTL_THLD	BIT(6)
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| #define RX_HW_FLOW_CTL_EN	BIT(7)
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| #define TX_HW_FLOW_CTL_EN	BIT(8)
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| #define RX_TOUT_THLD_DEF	0x3E00
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| #define RX_HFC_THLD_DEF	0x40
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| 
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| /* fifo threshold register */
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| #define SPRD_CTL2		0x0020
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| #define THLD_TX_EMPTY	0x40
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| #define THLD_RX_FULL	0x40
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| 
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| /* config baud rate register */
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| #define SPRD_CLKD0		0x0024
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| #define SPRD_CLKD1		0x0028
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| 
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| /* interrupt mask status register */
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| #define SPRD_IMSR			0x002C
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| #define SPRD_IMSR_RX_FIFO_FULL		BIT(0)
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| #define SPRD_IMSR_TX_FIFO_EMPTY	BIT(1)
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| #define SPRD_IMSR_BREAK_DETECT		BIT(7)
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| #define SPRD_IMSR_TIMEOUT		BIT(13)
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| 
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| struct reg_backup {
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| 	u32 ien;
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| 	u32 ctrl0;
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| 	u32 ctrl1;
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| 	u32 ctrl2;
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| 	u32 clkd0;
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| 	u32 clkd1;
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| 	u32 dspwait;
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| };
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| 
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| struct sprd_uart_port {
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| 	struct uart_port port;
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| 	struct reg_backup reg_bak;
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| 	char name[16];
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| };
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| 
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| static struct sprd_uart_port *sprd_port[UART_NR_MAX];
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| static int sprd_ports_num;
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| 
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| static inline unsigned int serial_in(struct uart_port *port, int offset)
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| {
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| 	return readl_relaxed(port->membase + offset);
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| }
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| 
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| static inline void serial_out(struct uart_port *port, int offset, int value)
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| {
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| 	writel_relaxed(value, port->membase + offset);
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| }
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| 
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| static unsigned int sprd_tx_empty(struct uart_port *port)
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| {
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| 	if (serial_in(port, SPRD_STS1) & 0xff00)
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| 		return 0;
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| 	else
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| 		return TIOCSER_TEMT;
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| }
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| 
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| static unsigned int sprd_get_mctrl(struct uart_port *port)
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| {
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| 	return TIOCM_DSR | TIOCM_CTS;
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| }
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| 
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| static void sprd_set_mctrl(struct uart_port *port, unsigned int mctrl)
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| {
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| 	/* nothing to do */
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| }
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| 
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| static void sprd_stop_tx(struct uart_port *port)
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| {
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| 	unsigned int ien, iclr;
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| 
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| 	iclr = serial_in(port, SPRD_ICLR);
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| 	ien = serial_in(port, SPRD_IEN);
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| 
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| 	iclr |= SPRD_IEN_TX_EMPTY;
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| 	ien &= ~SPRD_IEN_TX_EMPTY;
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| 
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| 	serial_out(port, SPRD_ICLR, iclr);
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| 	serial_out(port, SPRD_IEN, ien);
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| }
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| 
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| static void sprd_start_tx(struct uart_port *port)
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| {
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| 	unsigned int ien;
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| 
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| 	ien = serial_in(port, SPRD_IEN);
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| 	if (!(ien & SPRD_IEN_TX_EMPTY)) {
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| 		ien |= SPRD_IEN_TX_EMPTY;
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| 		serial_out(port, SPRD_IEN, ien);
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| 	}
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| }
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| 
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| static void sprd_stop_rx(struct uart_port *port)
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| {
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| 	unsigned int ien, iclr;
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| 
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| 	iclr = serial_in(port, SPRD_ICLR);
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| 	ien = serial_in(port, SPRD_IEN);
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| 
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| 	ien &= ~(SPRD_IEN_RX_FULL | SPRD_IEN_BREAK_DETECT);
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| 	iclr |= SPRD_IEN_RX_FULL | SPRD_IEN_BREAK_DETECT;
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| 
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| 	serial_out(port, SPRD_IEN, ien);
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| 	serial_out(port, SPRD_ICLR, iclr);
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| }
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| 
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| /* The Sprd serial does not support this function. */
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| static void sprd_break_ctl(struct uart_port *port, int break_state)
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| {
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| 	/* nothing to do */
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| }
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| 
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| static int handle_lsr_errors(struct uart_port *port,
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| 			     unsigned int *flag,
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| 			     unsigned int *lsr)
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| {
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| 	int ret = 0;
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| 
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| 	/* statistics */
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| 	if (*lsr & SPRD_LSR_BI) {
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| 		*lsr &= ~(SPRD_LSR_FE | SPRD_LSR_PE);
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| 		port->icount.brk++;
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| 		ret = uart_handle_break(port);
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| 		if (ret)
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| 			return ret;
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| 	} else if (*lsr & SPRD_LSR_PE)
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| 		port->icount.parity++;
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| 	else if (*lsr & SPRD_LSR_FE)
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| 		port->icount.frame++;
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| 	if (*lsr & SPRD_LSR_OE)
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| 		port->icount.overrun++;
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| 
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| 	/* mask off conditions which should be ignored */
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| 	*lsr &= port->read_status_mask;
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| 	if (*lsr & SPRD_LSR_BI)
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| 		*flag = TTY_BREAK;
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| 	else if (*lsr & SPRD_LSR_PE)
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| 		*flag = TTY_PARITY;
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| 	else if (*lsr & SPRD_LSR_FE)
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| 		*flag = TTY_FRAME;
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| 
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| 	return ret;
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| }
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| 
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| static inline void sprd_rx(struct uart_port *port)
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| {
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| 	struct tty_port *tty = &port->state->port;
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| 	unsigned int ch, flag, lsr, max_count = SPRD_TIMEOUT;
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| 
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| 	while ((serial_in(port, SPRD_STS1) & 0x00ff) && max_count--) {
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| 		lsr = serial_in(port, SPRD_LSR);
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| 		ch = serial_in(port, SPRD_RXD);
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| 		flag = TTY_NORMAL;
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| 		port->icount.rx++;
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| 
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| 		if (lsr & (SPRD_LSR_BI | SPRD_LSR_PE |
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| 			SPRD_LSR_FE | SPRD_LSR_OE))
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| 			if (handle_lsr_errors(port, &flag, &lsr))
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| 				continue;
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| 		if (uart_handle_sysrq_char(port, ch))
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| 			continue;
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| 
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| 		uart_insert_char(port, lsr, SPRD_LSR_OE, ch, flag);
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| 	}
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| 
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| 	tty_flip_buffer_push(tty);
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| }
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| 
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| static inline void sprd_tx(struct uart_port *port)
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| {
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| 	struct circ_buf *xmit = &port->state->xmit;
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| 	int count;
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| 
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| 	if (port->x_char) {
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| 		serial_out(port, SPRD_TXD, port->x_char);
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| 		port->icount.tx++;
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| 		port->x_char = 0;
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| 		return;
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| 	}
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| 
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| 	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
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| 		sprd_stop_tx(port);
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| 		return;
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| 	}
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| 
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| 	count = THLD_TX_EMPTY;
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| 	do {
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| 		serial_out(port, SPRD_TXD, xmit->buf[xmit->tail]);
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| 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
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| 		port->icount.tx++;
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| 		if (uart_circ_empty(xmit))
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| 			break;
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| 	} while (--count > 0);
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| 
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| 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
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| 		uart_write_wakeup(port);
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| 
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| 	if (uart_circ_empty(xmit))
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| 		sprd_stop_tx(port);
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| }
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| 
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| /* this handles the interrupt from one port */
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| static irqreturn_t sprd_handle_irq(int irq, void *dev_id)
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| {
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| 	struct uart_port *port = dev_id;
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| 	unsigned int ims;
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| 
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| 	spin_lock(&port->lock);
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| 
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| 	ims = serial_in(port, SPRD_IMSR);
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| 
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| 	if (!ims) {
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| 		spin_unlock(&port->lock);
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| 		return IRQ_NONE;
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| 	}
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| 
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| 	if (ims & SPRD_IMSR_TIMEOUT)
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| 		serial_out(port, SPRD_ICLR, SPRD_ICLR_TIMEOUT);
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| 
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| 	if (ims & (SPRD_IMSR_RX_FIFO_FULL |
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| 		SPRD_IMSR_BREAK_DETECT | SPRD_IMSR_TIMEOUT))
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| 		sprd_rx(port);
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| 
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| 	if (ims & SPRD_IMSR_TX_FIFO_EMPTY)
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| 		sprd_tx(port);
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| 
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| 	spin_unlock(&port->lock);
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| 
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| 	return IRQ_HANDLED;
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| }
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| 
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| static int sprd_startup(struct uart_port *port)
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| {
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| 	int ret = 0;
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| 	unsigned int ien, fc;
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| 	unsigned int timeout;
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| 	struct sprd_uart_port *sp;
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| 	unsigned long flags;
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| 
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| 	serial_out(port, SPRD_CTL2, ((THLD_TX_EMPTY << 8) | THLD_RX_FULL));
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| 
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| 	/* clear rx fifo */
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| 	timeout = SPRD_TIMEOUT;
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| 	while (timeout-- && serial_in(port, SPRD_STS1) & 0x00ff)
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| 		serial_in(port, SPRD_RXD);
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| 
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| 	/* clear tx fifo */
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| 	timeout = SPRD_TIMEOUT;
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| 	while (timeout-- && serial_in(port, SPRD_STS1) & 0xff00)
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| 		cpu_relax();
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| 
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| 	/* clear interrupt */
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| 	serial_out(port, SPRD_IEN, 0);
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| 	serial_out(port, SPRD_ICLR, ~0);
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| 
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| 	/* allocate irq */
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| 	sp = container_of(port, struct sprd_uart_port, port);
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| 	snprintf(sp->name, sizeof(sp->name), "sprd_serial%d", port->line);
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| 	ret = devm_request_irq(port->dev, port->irq, sprd_handle_irq,
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| 				IRQF_SHARED, sp->name, port);
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| 	if (ret) {
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| 		dev_err(port->dev, "fail to request serial irq %d, ret=%d\n",
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| 			port->irq, ret);
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| 		return ret;
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| 	}
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| 	fc = serial_in(port, SPRD_CTL1);
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| 	fc |= RX_TOUT_THLD_DEF | RX_HFC_THLD_DEF;
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| 	serial_out(port, SPRD_CTL1, fc);
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| 
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| 	/* enable interrupt */
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| 	spin_lock_irqsave(&port->lock, flags);
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| 	ien = serial_in(port, SPRD_IEN);
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| 	ien |= SPRD_IEN_RX_FULL | SPRD_IEN_BREAK_DETECT | SPRD_IEN_TIMEOUT;
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| 	serial_out(port, SPRD_IEN, ien);
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| 	spin_unlock_irqrestore(&port->lock, flags);
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| 
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| 	return 0;
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| }
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| 
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| static void sprd_shutdown(struct uart_port *port)
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| {
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| 	serial_out(port, SPRD_IEN, 0);
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| 	serial_out(port, SPRD_ICLR, ~0);
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| 	devm_free_irq(port->dev, port->irq, port);
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| }
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| 
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| static void sprd_set_termios(struct uart_port *port,
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| 				    struct ktermios *termios,
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| 				    struct ktermios *old)
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| {
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| 	unsigned int baud, quot;
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| 	unsigned int lcr = 0, fc;
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| 	unsigned long flags;
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| 
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| 	/* ask the core to calculate the divisor for us */
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| 	baud = uart_get_baud_rate(port, termios, old, 0, SPRD_BAUD_IO_LIMIT);
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| 
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| 	quot = (unsigned int)((port->uartclk + baud / 2) / baud);
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| 
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| 	/* set data length */
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| 	switch (termios->c_cflag & CSIZE) {
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| 	case CS5:
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| 		lcr |= SPRD_LCR_DATA_LEN5;
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| 		break;
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| 	case CS6:
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| 		lcr |= SPRD_LCR_DATA_LEN6;
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| 		break;
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| 	case CS7:
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| 		lcr |= SPRD_LCR_DATA_LEN7;
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| 		break;
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| 	case CS8:
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| 	default:
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| 		lcr |= SPRD_LCR_DATA_LEN8;
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| 		break;
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| 	}
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| 
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| 	/* calculate stop bits */
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| 	lcr &= ~(SPRD_LCR_STOP_1BIT | SPRD_LCR_STOP_2BIT);
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| 	if (termios->c_cflag & CSTOPB)
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| 		lcr |= SPRD_LCR_STOP_2BIT;
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| 	else
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| 		lcr |= SPRD_LCR_STOP_1BIT;
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| 
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| 	/* calculate parity */
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| 	lcr &= ~SPRD_LCR_PARITY;
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| 	termios->c_cflag &= ~CMSPAR;	/* no support mark/space */
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| 	if (termios->c_cflag & PARENB) {
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| 		lcr |= SPRD_LCR_PARITY_EN;
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| 		if (termios->c_cflag & PARODD)
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| 			lcr |= SPRD_LCR_ODD_PAR;
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| 		else
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| 			lcr |= SPRD_LCR_EVEN_PAR;
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| 	}
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| 
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| 	spin_lock_irqsave(&port->lock, flags);
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| 
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| 	/* update the per-port timeout */
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| 	uart_update_timeout(port, termios->c_cflag, baud);
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| 
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| 	port->read_status_mask = SPRD_LSR_OE;
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| 	if (termios->c_iflag & INPCK)
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| 		port->read_status_mask |= SPRD_LSR_FE | SPRD_LSR_PE;
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| 	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
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| 		port->read_status_mask |= SPRD_LSR_BI;
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| 
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| 	/* characters to ignore */
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| 	port->ignore_status_mask = 0;
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| 	if (termios->c_iflag & IGNPAR)
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| 		port->ignore_status_mask |= SPRD_LSR_PE | SPRD_LSR_FE;
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| 	if (termios->c_iflag & IGNBRK) {
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| 		port->ignore_status_mask |= SPRD_LSR_BI;
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| 		/*
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| 		 * If we're ignoring parity and break indicators,
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| 		 * ignore overruns too (for real raw support).
 | |
| 		 */
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| 		if (termios->c_iflag & IGNPAR)
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| 			port->ignore_status_mask |= SPRD_LSR_OE;
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| 	}
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| 
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| 	/* flow control */
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| 	fc = serial_in(port, SPRD_CTL1);
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| 	fc &= ~(RX_HW_FLOW_CTL_THLD | RX_HW_FLOW_CTL_EN | TX_HW_FLOW_CTL_EN);
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| 	if (termios->c_cflag & CRTSCTS) {
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| 		fc |= RX_HW_FLOW_CTL_THLD;
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| 		fc |= RX_HW_FLOW_CTL_EN;
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| 		fc |= TX_HW_FLOW_CTL_EN;
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| 	}
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| 
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| 	/* clock divider bit0~bit15 */
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| 	serial_out(port, SPRD_CLKD0, quot & 0xffff);
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| 
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| 	/* clock divider bit16~bit20 */
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| 	serial_out(port, SPRD_CLKD1, (quot & 0x1f0000) >> 16);
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| 	serial_out(port, SPRD_LCR, lcr);
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| 	fc |= RX_TOUT_THLD_DEF | RX_HFC_THLD_DEF;
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| 	serial_out(port, SPRD_CTL1, fc);
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| 
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| 	spin_unlock_irqrestore(&port->lock, flags);
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| 
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| 	/* Don't rewrite B0 */
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| 	if (tty_termios_baud_rate(termios))
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| 		tty_termios_encode_baud_rate(termios, baud, baud);
 | |
| }
 | |
| 
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| static const char *sprd_type(struct uart_port *port)
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| {
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| 	return "SPX";
 | |
| }
 | |
| 
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| static void sprd_release_port(struct uart_port *port)
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| {
 | |
| 	/* nothing to do */
 | |
| }
 | |
| 
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| static int sprd_request_port(struct uart_port *port)
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| {
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| 	return 0;
 | |
| }
 | |
| 
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| static void sprd_config_port(struct uart_port *port, int flags)
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| {
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| 	if (flags & UART_CONFIG_TYPE)
 | |
| 		port->type = PORT_SPRD;
 | |
| }
 | |
| 
 | |
| static int sprd_verify_port(struct uart_port *port,
 | |
| 				   struct serial_struct *ser)
 | |
| {
 | |
| 	if (ser->type != PORT_SPRD)
 | |
| 		return -EINVAL;
 | |
| 	if (port->irq != ser->irq)
 | |
| 		return -EINVAL;
 | |
| 	if (port->iotype != ser->io_type)
 | |
| 		return -EINVAL;
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static const struct uart_ops serial_sprd_ops = {
 | |
| 	.tx_empty = sprd_tx_empty,
 | |
| 	.get_mctrl = sprd_get_mctrl,
 | |
| 	.set_mctrl = sprd_set_mctrl,
 | |
| 	.stop_tx = sprd_stop_tx,
 | |
| 	.start_tx = sprd_start_tx,
 | |
| 	.stop_rx = sprd_stop_rx,
 | |
| 	.break_ctl = sprd_break_ctl,
 | |
| 	.startup = sprd_startup,
 | |
| 	.shutdown = sprd_shutdown,
 | |
| 	.set_termios = sprd_set_termios,
 | |
| 	.type = sprd_type,
 | |
| 	.release_port = sprd_release_port,
 | |
| 	.request_port = sprd_request_port,
 | |
| 	.config_port = sprd_config_port,
 | |
| 	.verify_port = sprd_verify_port,
 | |
| };
 | |
| 
 | |
| #ifdef CONFIG_SERIAL_SPRD_CONSOLE
 | |
| static void wait_for_xmitr(struct uart_port *port)
 | |
| {
 | |
| 	unsigned int status, tmout = 10000;
 | |
| 
 | |
| 	/* wait up to 10ms for the character(s) to be sent */
 | |
| 	do {
 | |
| 		status = serial_in(port, SPRD_STS1);
 | |
| 		if (--tmout == 0)
 | |
| 			break;
 | |
| 		udelay(1);
 | |
| 	} while (status & 0xff00);
 | |
| }
 | |
| 
 | |
| static void sprd_console_putchar(struct uart_port *port, int ch)
 | |
| {
 | |
| 	wait_for_xmitr(port);
 | |
| 	serial_out(port, SPRD_TXD, ch);
 | |
| }
 | |
| 
 | |
| static void sprd_console_write(struct console *co, const char *s,
 | |
| 				      unsigned int count)
 | |
| {
 | |
| 	struct uart_port *port = &sprd_port[co->index]->port;
 | |
| 	int locked = 1;
 | |
| 	unsigned long flags;
 | |
| 
 | |
| 	if (port->sysrq)
 | |
| 		locked = 0;
 | |
| 	else if (oops_in_progress)
 | |
| 		locked = spin_trylock_irqsave(&port->lock, flags);
 | |
| 	else
 | |
| 		spin_lock_irqsave(&port->lock, flags);
 | |
| 
 | |
| 	uart_console_write(port, s, count, sprd_console_putchar);
 | |
| 
 | |
| 	/* wait for transmitter to become empty */
 | |
| 	wait_for_xmitr(port);
 | |
| 
 | |
| 	if (locked)
 | |
| 		spin_unlock_irqrestore(&port->lock, flags);
 | |
| }
 | |
| 
 | |
| static int __init sprd_console_setup(struct console *co, char *options)
 | |
| {
 | |
| 	struct uart_port *port;
 | |
| 	int baud = 115200;
 | |
| 	int bits = 8;
 | |
| 	int parity = 'n';
 | |
| 	int flow = 'n';
 | |
| 
 | |
| 	if (co->index >= UART_NR_MAX || co->index < 0)
 | |
| 		co->index = 0;
 | |
| 
 | |
| 	port = &sprd_port[co->index]->port;
 | |
| 	if (port == NULL) {
 | |
| 		pr_info("serial port %d not yet initialized\n", co->index);
 | |
| 		return -ENODEV;
 | |
| 	}
 | |
| 	if (options)
 | |
| 		uart_parse_options(options, &baud, &parity, &bits, &flow);
 | |
| 
 | |
| 	return uart_set_options(port, co, baud, parity, bits, flow);
 | |
| }
 | |
| 
 | |
| static struct uart_driver sprd_uart_driver;
 | |
| static struct console sprd_console = {
 | |
| 	.name = SPRD_TTY_NAME,
 | |
| 	.write = sprd_console_write,
 | |
| 	.device = uart_console_device,
 | |
| 	.setup = sprd_console_setup,
 | |
| 	.flags = CON_PRINTBUFFER,
 | |
| 	.index = -1,
 | |
| 	.data = &sprd_uart_driver,
 | |
| };
 | |
| 
 | |
| #define SPRD_CONSOLE	(&sprd_console)
 | |
| 
 | |
| /* Support for earlycon */
 | |
| static void sprd_putc(struct uart_port *port, int c)
 | |
| {
 | |
| 	unsigned int timeout = SPRD_TIMEOUT;
 | |
| 
 | |
| 	while (timeout-- &&
 | |
| 		   !(readl(port->membase + SPRD_LSR) & SPRD_LSR_TX_OVER))
 | |
| 		cpu_relax();
 | |
| 
 | |
| 	writeb(c, port->membase + SPRD_TXD);
 | |
| }
 | |
| 
 | |
| static void sprd_early_write(struct console *con, const char *s,
 | |
| 				    unsigned n)
 | |
| {
 | |
| 	struct earlycon_device *dev = con->data;
 | |
| 
 | |
| 	uart_console_write(&dev->port, s, n, sprd_putc);
 | |
| }
 | |
| 
 | |
| static int __init sprd_early_console_setup(
 | |
| 				struct earlycon_device *device,
 | |
| 				const char *opt)
 | |
| {
 | |
| 	if (!device->port.membase)
 | |
| 		return -ENODEV;
 | |
| 
 | |
| 	device->con->write = sprd_early_write;
 | |
| 	return 0;
 | |
| }
 | |
| OF_EARLYCON_DECLARE(sprd_serial, "sprd,sc9836-uart",
 | |
| 		    sprd_early_console_setup);
 | |
| 
 | |
| #else /* !CONFIG_SERIAL_SPRD_CONSOLE */
 | |
| #define SPRD_CONSOLE		NULL
 | |
| #endif
 | |
| 
 | |
| static struct uart_driver sprd_uart_driver = {
 | |
| 	.owner = THIS_MODULE,
 | |
| 	.driver_name = "sprd_serial",
 | |
| 	.dev_name = SPRD_TTY_NAME,
 | |
| 	.major = 0,
 | |
| 	.minor = 0,
 | |
| 	.nr = UART_NR_MAX,
 | |
| 	.cons = SPRD_CONSOLE,
 | |
| };
 | |
| 
 | |
| static int sprd_probe_dt_alias(int index, struct device *dev)
 | |
| {
 | |
| 	struct device_node *np;
 | |
| 	int ret = index;
 | |
| 
 | |
| 	if (!IS_ENABLED(CONFIG_OF))
 | |
| 		return ret;
 | |
| 
 | |
| 	np = dev->of_node;
 | |
| 	if (!np)
 | |
| 		return ret;
 | |
| 
 | |
| 	ret = of_alias_get_id(np, "serial");
 | |
| 	if (ret < 0)
 | |
| 		ret = index;
 | |
| 	else if (ret >= ARRAY_SIZE(sprd_port) || sprd_port[ret] != NULL) {
 | |
| 		dev_warn(dev, "requested serial port %d not available.\n", ret);
 | |
| 		ret = index;
 | |
| 	}
 | |
| 
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| static int sprd_remove(struct platform_device *dev)
 | |
| {
 | |
| 	struct sprd_uart_port *sup = platform_get_drvdata(dev);
 | |
| 
 | |
| 	if (sup) {
 | |
| 		uart_remove_one_port(&sprd_uart_driver, &sup->port);
 | |
| 		sprd_port[sup->port.line] = NULL;
 | |
| 		sprd_ports_num--;
 | |
| 	}
 | |
| 
 | |
| 	if (!sprd_ports_num)
 | |
| 		uart_unregister_driver(&sprd_uart_driver);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int sprd_probe(struct platform_device *pdev)
 | |
| {
 | |
| 	struct resource *res;
 | |
| 	struct uart_port *up;
 | |
| 	struct clk *clk;
 | |
| 	int irq;
 | |
| 	int index;
 | |
| 	int ret;
 | |
| 
 | |
| 	for (index = 0; index < ARRAY_SIZE(sprd_port); index++)
 | |
| 		if (sprd_port[index] == NULL)
 | |
| 			break;
 | |
| 
 | |
| 	if (index == ARRAY_SIZE(sprd_port))
 | |
| 		return -EBUSY;
 | |
| 
 | |
| 	index = sprd_probe_dt_alias(index, &pdev->dev);
 | |
| 
 | |
| 	sprd_port[index] = devm_kzalloc(&pdev->dev,
 | |
| 		sizeof(*sprd_port[index]), GFP_KERNEL);
 | |
| 	if (!sprd_port[index])
 | |
| 		return -ENOMEM;
 | |
| 
 | |
| 	up = &sprd_port[index]->port;
 | |
| 	up->dev = &pdev->dev;
 | |
| 	up->line = index;
 | |
| 	up->type = PORT_SPRD;
 | |
| 	up->iotype = UPIO_MEM;
 | |
| 	up->uartclk = SPRD_DEF_RATE;
 | |
| 	up->fifosize = SPRD_FIFO_SIZE;
 | |
| 	up->ops = &serial_sprd_ops;
 | |
| 	up->flags = UPF_BOOT_AUTOCONF;
 | |
| 
 | |
| 	clk = devm_clk_get(&pdev->dev, NULL);
 | |
| 	if (!IS_ERR_OR_NULL(clk))
 | |
| 		up->uartclk = clk_get_rate(clk);
 | |
| 
 | |
| 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 | |
| 	if (!res) {
 | |
| 		dev_err(&pdev->dev, "not provide mem resource\n");
 | |
| 		return -ENODEV;
 | |
| 	}
 | |
| 	up->mapbase = res->start;
 | |
| 	up->membase = devm_ioremap_resource(&pdev->dev, res);
 | |
| 	if (IS_ERR(up->membase))
 | |
| 		return PTR_ERR(up->membase);
 | |
| 
 | |
| 	irq = platform_get_irq(pdev, 0);
 | |
| 	if (irq < 0) {
 | |
| 		dev_err(&pdev->dev, "not provide irq resource: %d\n", irq);
 | |
| 		return irq;
 | |
| 	}
 | |
| 	up->irq = irq;
 | |
| 
 | |
| 	if (!sprd_ports_num) {
 | |
| 		ret = uart_register_driver(&sprd_uart_driver);
 | |
| 		if (ret < 0) {
 | |
| 			pr_err("Failed to register SPRD-UART driver\n");
 | |
| 			return ret;
 | |
| 		}
 | |
| 	}
 | |
| 	sprd_ports_num++;
 | |
| 
 | |
| 	ret = uart_add_one_port(&sprd_uart_driver, up);
 | |
| 	if (ret) {
 | |
| 		sprd_port[index] = NULL;
 | |
| 		sprd_remove(pdev);
 | |
| 	}
 | |
| 
 | |
| 	platform_set_drvdata(pdev, up);
 | |
| 
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| #ifdef CONFIG_PM_SLEEP
 | |
| static int sprd_suspend(struct device *dev)
 | |
| {
 | |
| 	struct sprd_uart_port *sup = dev_get_drvdata(dev);
 | |
| 
 | |
| 	uart_suspend_port(&sprd_uart_driver, &sup->port);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int sprd_resume(struct device *dev)
 | |
| {
 | |
| 	struct sprd_uart_port *sup = dev_get_drvdata(dev);
 | |
| 
 | |
| 	uart_resume_port(&sprd_uart_driver, &sup->port);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| #endif
 | |
| 
 | |
| static SIMPLE_DEV_PM_OPS(sprd_pm_ops, sprd_suspend, sprd_resume);
 | |
| 
 | |
| static const struct of_device_id serial_ids[] = {
 | |
| 	{.compatible = "sprd,sc9836-uart",},
 | |
| 	{}
 | |
| };
 | |
| MODULE_DEVICE_TABLE(of, serial_ids);
 | |
| 
 | |
| static struct platform_driver sprd_platform_driver = {
 | |
| 	.probe		= sprd_probe,
 | |
| 	.remove		= sprd_remove,
 | |
| 	.driver		= {
 | |
| 		.name	= "sprd_serial",
 | |
| 		.of_match_table = of_match_ptr(serial_ids),
 | |
| 		.pm	= &sprd_pm_ops,
 | |
| 	},
 | |
| };
 | |
| 
 | |
| module_platform_driver(sprd_platform_driver);
 | |
| 
 | |
| MODULE_LICENSE("GPL v2");
 | |
| MODULE_DESCRIPTION("Spreadtrum SoC serial driver series");
 | 
