794 lines
18 KiB
C
794 lines
18 KiB
C
![]() |
/*
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* Copyright (C) 2012-2015 Spreadtrum Communications Inc.
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*
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* This software is licensed under the terms of the GNU General Public
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* License version 2, as published by the Free Software Foundation, and
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* may be copied, distributed, and modified under those terms.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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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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#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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/* 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 256
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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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/* 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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/* data number in TX and RX fifo */
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#define SPRD_STS1 0x000C
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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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/* interrupt clear register */
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#define SPRD_ICLR 0x0014
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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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/* 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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/* 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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/* config baud rate register */
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#define SPRD_CLKD0 0x0024
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#define SPRD_CLKD1 0x0028
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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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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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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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static struct sprd_uart_port *sprd_port[UART_NR_MAX];
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static int sprd_ports_num;
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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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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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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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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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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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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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iclr = serial_in(port, SPRD_ICLR);
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ien = serial_in(port, SPRD_IEN);
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iclr |= SPRD_IEN_TX_EMPTY;
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ien &= ~SPRD_IEN_TX_EMPTY;
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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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static void sprd_start_tx(struct uart_port *port)
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{
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unsigned int ien;
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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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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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iclr = serial_in(port, SPRD_ICLR);
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ien = serial_in(port, SPRD_IEN);
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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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serial_out(port, SPRD_IEN, ien);
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serial_out(port, SPRD_ICLR, iclr);
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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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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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/* 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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/* 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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return ret;
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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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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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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, &lsr, &flag))
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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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uart_insert_char(port, lsr, SPRD_LSR_OE, ch, flag);
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}
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tty_flip_buffer_push(tty);
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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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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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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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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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if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
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uart_write_wakeup(port);
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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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/* 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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spin_lock(&port->lock);
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ims = serial_in(port, SPRD_IMSR);
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if (!ims)
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return IRQ_NONE;
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serial_out(port, SPRD_ICLR, ~0);
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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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if (ims & SPRD_IMSR_TX_FIFO_EMPTY)
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sprd_tx(port);
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spin_unlock(&port->lock);
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return IRQ_HANDLED;
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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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serial_out(port, SPRD_CTL2, ((THLD_TX_EMPTY << 8) | THLD_RX_FULL));
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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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/* 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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/* 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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/* 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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/* 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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return 0;
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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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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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/* 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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quot = (unsigned int)((port->uartclk + baud / 2) / baud);
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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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/* 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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/* 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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spin_lock_irqsave(&port->lock, flags);
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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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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;
|
||
|
if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
|
||
|
port->read_status_mask |= SPRD_LSR_BI;
|
||
|
|
||
|
/* characters to ignore */
|
||
|
port->ignore_status_mask = 0;
|
||
|
if (termios->c_iflag & IGNPAR)
|
||
|
port->ignore_status_mask |= SPRD_LSR_PE | SPRD_LSR_FE;
|
||
|
if (termios->c_iflag & IGNBRK) {
|
||
|
port->ignore_status_mask |= SPRD_LSR_BI;
|
||
|
/*
|
||
|
* If we're ignoring parity and break indicators,
|
||
|
* ignore overruns too (for real raw support).
|
||
|
*/
|
||
|
if (termios->c_iflag & IGNPAR)
|
||
|
port->ignore_status_mask |= SPRD_LSR_OE;
|
||
|
}
|
||
|
|
||
|
/* flow control */
|
||
|
fc = serial_in(port, SPRD_CTL1);
|
||
|
fc &= ~(RX_HW_FLOW_CTL_THLD | RX_HW_FLOW_CTL_EN | TX_HW_FLOW_CTL_EN);
|
||
|
if (termios->c_cflag & CRTSCTS) {
|
||
|
fc |= RX_HW_FLOW_CTL_THLD;
|
||
|
fc |= RX_HW_FLOW_CTL_EN;
|
||
|
fc |= TX_HW_FLOW_CTL_EN;
|
||
|
}
|
||
|
|
||
|
/* clock divider bit0~bit15 */
|
||
|
serial_out(port, SPRD_CLKD0, quot & 0xffff);
|
||
|
|
||
|
/* clock divider bit16~bit20 */
|
||
|
serial_out(port, SPRD_CLKD1, (quot & 0x1f0000) >> 16);
|
||
|
serial_out(port, SPRD_LCR, lcr);
|
||
|
fc |= RX_TOUT_THLD_DEF | RX_HFC_THLD_DEF;
|
||
|
serial_out(port, SPRD_CTL1, fc);
|
||
|
|
||
|
spin_unlock_irqrestore(&port->lock, flags);
|
||
|
|
||
|
/* Don't rewrite B0 */
|
||
|
if (tty_termios_baud_rate(termios))
|
||
|
tty_termios_encode_baud_rate(termios, baud, baud);
|
||
|
}
|
||
|
|
||
|
static const char *sprd_type(struct uart_port *port)
|
||
|
{
|
||
|
return "SPX";
|
||
|
}
|
||
|
|
||
|
static void sprd_release_port(struct uart_port *port)
|
||
|
{
|
||
|
/* nothing to do */
|
||
|
}
|
||
|
|
||
|
static int sprd_request_port(struct uart_port *port)
|
||
|
{
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static void sprd_config_port(struct uart_port *port, int flags)
|
||
|
{
|
||
|
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;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static 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 inline 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;
|
||
|
}
|
||
|
|
||
|
EARLYCON_DECLARE(sprd_serial, sprd_early_console_setup);
|
||
|
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 (IS_ERR_VALUE(ret))
|
||
|
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 = SERIAL_IO_PORT;
|
||
|
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(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\n");
|
||
|
return -ENODEV;
|
||
|
}
|
||
|
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;
|
||
|
}
|
||
|
|
||
|
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;
|
||
|
}
|
||
|
|
||
|
static SIMPLE_DEV_PM_OPS(sprd_pm_ops, sprd_suspend, sprd_resume);
|
||
|
|
||
|
static const struct of_device_id serial_ids[] = {
|
||
|
{.compatible = "sprd,sc9836-uart",},
|
||
|
{}
|
||
|
};
|
||
|
|
||
|
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");
|