784 lines
19 KiB
C
784 lines
19 KiB
C
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// SPDX-License-Identifier: GPL-2.0+
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/*
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* Synopsys DesignWare 8250 driver.
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*
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* Copyright 2011 Picochip, Jamie Iles.
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* Copyright 2013 Intel Corporation
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*
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* The Synopsys DesignWare 8250 has an extra feature whereby it detects if the
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* LCR is written whilst busy. If it is, then a busy detect interrupt is
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* raised, the LCR needs to be rewritten and the uart status register read.
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*/
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#include <linux/delay.h>
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#include <linux/device.h>
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#include <linux/io.h>
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#include <linux/module.h>
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#include <linux/serial_8250.h>
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#include <linux/serial_reg.h>
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#include <linux/of.h>
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#include <linux/of_irq.h>
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#include <linux/of_platform.h>
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#include <linux/platform_device.h>
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#include <linux/slab.h>
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#include <linux/acpi.h>
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#include <linux/clk.h>
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#include <linux/reset.h>
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#include <linux/pm_runtime.h>
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#include <asm/byteorder.h>
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#include "8250.h"
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/* Offsets for the DesignWare specific registers */
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#define DW_UART_USR 0x1f /* UART Status Register */
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#define DW_UART_DLF 0xc0 /* Divisor Latch Fraction Register */
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#define DW_UART_CPR 0xf4 /* Component Parameter Register */
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#define DW_UART_UCV 0xf8 /* UART Component Version */
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/* Component Parameter Register bits */
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#define DW_UART_CPR_ABP_DATA_WIDTH (3 << 0)
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#define DW_UART_CPR_AFCE_MODE (1 << 4)
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#define DW_UART_CPR_THRE_MODE (1 << 5)
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#define DW_UART_CPR_SIR_MODE (1 << 6)
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#define DW_UART_CPR_SIR_LP_MODE (1 << 7)
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#define DW_UART_CPR_ADDITIONAL_FEATURES (1 << 8)
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#define DW_UART_CPR_FIFO_ACCESS (1 << 9)
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#define DW_UART_CPR_FIFO_STAT (1 << 10)
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#define DW_UART_CPR_SHADOW (1 << 11)
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#define DW_UART_CPR_ENCODED_PARMS (1 << 12)
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#define DW_UART_CPR_DMA_EXTRA (1 << 13)
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#define DW_UART_CPR_FIFO_MODE (0xff << 16)
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/* Helper for fifo size calculation */
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#define DW_UART_CPR_FIFO_SIZE(a) (((a >> 16) & 0xff) * 16)
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/* DesignWare specific register fields */
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#define DW_UART_MCR_SIRE BIT(6)
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struct dw8250_data {
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u8 usr_reg;
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u8 dlf_size;
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int line;
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int msr_mask_on;
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int msr_mask_off;
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struct clk *clk;
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struct clk *pclk;
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struct reset_control *rst;
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struct uart_8250_dma dma;
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unsigned int skip_autocfg:1;
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unsigned int uart_16550_compatible:1;
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};
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static inline u32 dw8250_readl_ext(struct uart_port *p, int offset)
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{
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if (p->iotype == UPIO_MEM32BE)
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return ioread32be(p->membase + offset);
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return readl(p->membase + offset);
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}
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static inline void dw8250_writel_ext(struct uart_port *p, int offset, u32 reg)
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{
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if (p->iotype == UPIO_MEM32BE)
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iowrite32be(reg, p->membase + offset);
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else
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writel(reg, p->membase + offset);
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}
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static inline int dw8250_modify_msr(struct uart_port *p, int offset, int value)
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{
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struct dw8250_data *d = p->private_data;
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/* Override any modem control signals if needed */
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if (offset == UART_MSR) {
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value |= d->msr_mask_on;
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value &= ~d->msr_mask_off;
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}
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return value;
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}
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static void dw8250_force_idle(struct uart_port *p)
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{
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struct uart_8250_port *up = up_to_u8250p(p);
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serial8250_clear_and_reinit_fifos(up);
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(void)p->serial_in(p, UART_RX);
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}
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static void dw8250_check_lcr(struct uart_port *p, int value)
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{
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void __iomem *offset = p->membase + (UART_LCR << p->regshift);
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int tries = 1000;
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/* Make sure LCR write wasn't ignored */
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while (tries--) {
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unsigned int lcr = p->serial_in(p, UART_LCR);
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if ((value & ~UART_LCR_SPAR) == (lcr & ~UART_LCR_SPAR))
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return;
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dw8250_force_idle(p);
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#ifdef CONFIG_64BIT
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if (p->type == PORT_OCTEON)
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__raw_writeq(value & 0xff, offset);
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else
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#endif
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if (p->iotype == UPIO_MEM32)
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writel(value, offset);
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else if (p->iotype == UPIO_MEM32BE)
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iowrite32be(value, offset);
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else
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writeb(value, offset);
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}
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/*
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* FIXME: this deadlocks if port->lock is already held
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* dev_err(p->dev, "Couldn't set LCR to %d\n", value);
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*/
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}
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/* Returns once the transmitter is empty or we run out of retries */
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static void dw8250_tx_wait_empty(struct uart_port *p)
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{
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unsigned int tries = 20000;
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unsigned int delay_threshold = tries - 1000;
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unsigned int lsr;
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while (tries--) {
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lsr = readb (p->membase + (UART_LSR << p->regshift));
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if (lsr & UART_LSR_TEMT)
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break;
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/* The device is first given a chance to empty without delay,
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* to avoid slowdowns at high bitrates. If after 1000 tries
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* the buffer has still not emptied, allow more time for low-
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* speed links. */
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if (tries < delay_threshold)
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udelay (1);
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}
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}
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static void dw8250_serial_out38x(struct uart_port *p, int offset, int value)
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{
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struct dw8250_data *d = p->private_data;
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/* Allow the TX to drain before we reconfigure */
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if (offset == UART_LCR)
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dw8250_tx_wait_empty(p);
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writeb(value, p->membase + (offset << p->regshift));
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if (offset == UART_LCR && !d->uart_16550_compatible)
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dw8250_check_lcr(p, value);
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}
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static void dw8250_serial_out(struct uart_port *p, int offset, int value)
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{
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struct dw8250_data *d = p->private_data;
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writeb(value, p->membase + (offset << p->regshift));
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if (offset == UART_LCR && !d->uart_16550_compatible)
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dw8250_check_lcr(p, value);
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}
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static unsigned int dw8250_serial_in(struct uart_port *p, int offset)
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{
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unsigned int value = readb(p->membase + (offset << p->regshift));
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return dw8250_modify_msr(p, offset, value);
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}
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#ifdef CONFIG_64BIT
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static unsigned int dw8250_serial_inq(struct uart_port *p, int offset)
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{
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unsigned int value;
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value = (u8)__raw_readq(p->membase + (offset << p->regshift));
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return dw8250_modify_msr(p, offset, value);
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}
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static void dw8250_serial_outq(struct uart_port *p, int offset, int value)
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{
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struct dw8250_data *d = p->private_data;
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value &= 0xff;
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__raw_writeq(value, p->membase + (offset << p->regshift));
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/* Read back to ensure register write ordering. */
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__raw_readq(p->membase + (UART_LCR << p->regshift));
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if (offset == UART_LCR && !d->uart_16550_compatible)
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dw8250_check_lcr(p, value);
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}
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#endif /* CONFIG_64BIT */
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static void dw8250_serial_out32(struct uart_port *p, int offset, int value)
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{
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struct dw8250_data *d = p->private_data;
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writel(value, p->membase + (offset << p->regshift));
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if (offset == UART_LCR && !d->uart_16550_compatible)
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dw8250_check_lcr(p, value);
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}
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static unsigned int dw8250_serial_in32(struct uart_port *p, int offset)
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{
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unsigned int value = readl(p->membase + (offset << p->regshift));
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return dw8250_modify_msr(p, offset, value);
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}
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static void dw8250_serial_out32be(struct uart_port *p, int offset, int value)
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{
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struct dw8250_data *d = p->private_data;
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iowrite32be(value, p->membase + (offset << p->regshift));
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if (offset == UART_LCR && !d->uart_16550_compatible)
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dw8250_check_lcr(p, value);
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}
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static unsigned int dw8250_serial_in32be(struct uart_port *p, int offset)
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{
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unsigned int value = ioread32be(p->membase + (offset << p->regshift));
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return dw8250_modify_msr(p, offset, value);
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}
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static int dw8250_handle_irq(struct uart_port *p)
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{
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struct uart_8250_port *up = up_to_u8250p(p);
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struct dw8250_data *d = p->private_data;
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unsigned int iir = p->serial_in(p, UART_IIR);
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unsigned int status;
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unsigned long flags;
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/*
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* There are ways to get Designware-based UARTs into a state where
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* they are asserting UART_IIR_RX_TIMEOUT but there is no actual
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* data available. If we see such a case then we'll do a bogus
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* read. If we don't do this then the "RX TIMEOUT" interrupt will
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* fire forever.
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*
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* This problem has only been observed so far when not in DMA mode
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* so we limit the workaround only to non-DMA mode.
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*/
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if (!up->dma && ((iir & 0x3f) == UART_IIR_RX_TIMEOUT)) {
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spin_lock_irqsave(&p->lock, flags);
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status = p->serial_in(p, UART_LSR);
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if (!(status & (UART_LSR_DR | UART_LSR_BI)))
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(void) p->serial_in(p, UART_RX);
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spin_unlock_irqrestore(&p->lock, flags);
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}
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if (serial8250_handle_irq(p, iir))
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return 1;
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if ((iir & UART_IIR_BUSY) == UART_IIR_BUSY) {
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/* Clear the USR */
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(void)p->serial_in(p, d->usr_reg);
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return 1;
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}
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return 0;
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}
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static void
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dw8250_do_pm(struct uart_port *port, unsigned int state, unsigned int old)
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{
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if (!state)
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pm_runtime_get_sync(port->dev);
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serial8250_do_pm(port, state, old);
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if (state)
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pm_runtime_put_sync_suspend(port->dev);
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}
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static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios,
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struct ktermios *old)
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{
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unsigned int baud = tty_termios_baud_rate(termios);
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struct dw8250_data *d = p->private_data;
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long rate;
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int ret;
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if (IS_ERR(d->clk))
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goto out;
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clk_disable_unprepare(d->clk);
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rate = clk_round_rate(d->clk, baud * 16);
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if (rate < 0)
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ret = rate;
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else if (rate == 0)
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ret = -ENOENT;
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else
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ret = clk_set_rate(d->clk, rate);
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clk_prepare_enable(d->clk);
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if (!ret)
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p->uartclk = rate;
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out:
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p->status &= ~UPSTAT_AUTOCTS;
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if (termios->c_cflag & CRTSCTS)
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p->status |= UPSTAT_AUTOCTS;
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serial8250_do_set_termios(p, termios, old);
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}
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static void dw8250_set_ldisc(struct uart_port *p, struct ktermios *termios)
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{
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struct uart_8250_port *up = up_to_u8250p(p);
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unsigned int mcr = p->serial_in(p, UART_MCR);
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if (up->capabilities & UART_CAP_IRDA) {
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if (termios->c_line == N_IRDA)
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mcr |= DW_UART_MCR_SIRE;
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else
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mcr &= ~DW_UART_MCR_SIRE;
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p->serial_out(p, UART_MCR, mcr);
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}
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serial8250_do_set_ldisc(p, termios);
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}
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/*
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* dw8250_fallback_dma_filter will prevent the UART from getting just any free
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* channel on platforms that have DMA engines, but don't have any channels
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* assigned to the UART.
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*
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* REVISIT: This is a work around for limitation in the DMA Engine API. Once the
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* core problem is fixed, this function is no longer needed.
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*/
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static bool dw8250_fallback_dma_filter(struct dma_chan *chan, void *param)
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{
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return false;
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}
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static bool dw8250_idma_filter(struct dma_chan *chan, void *param)
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{
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return param == chan->device->dev;
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}
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/*
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* divisor = div(I) + div(F)
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* "I" means integer, "F" means fractional
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* quot = div(I) = clk / (16 * baud)
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* frac = div(F) * 2^dlf_size
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*
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* let rem = clk % (16 * baud)
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* we have: div(F) * (16 * baud) = rem
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* so frac = 2^dlf_size * rem / (16 * baud) = (rem << dlf_size) / (16 * baud)
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*/
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static unsigned int dw8250_get_divisor(struct uart_port *p,
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unsigned int baud,
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unsigned int *frac)
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{
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unsigned int quot, rem, base_baud = baud * 16;
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struct dw8250_data *d = p->private_data;
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quot = p->uartclk / base_baud;
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rem = p->uartclk % base_baud;
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*frac = DIV_ROUND_CLOSEST(rem << d->dlf_size, base_baud);
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return quot;
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}
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static void dw8250_set_divisor(struct uart_port *p, unsigned int baud,
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unsigned int quot, unsigned int quot_frac)
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{
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dw8250_writel_ext(p, DW_UART_DLF, quot_frac);
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serial8250_do_set_divisor(p, baud, quot, quot_frac);
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}
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static void dw8250_quirks(struct uart_port *p, struct dw8250_data *data)
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{
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|
if (p->dev->of_node) {
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struct device_node *np = p->dev->of_node;
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int id;
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/* get index of serial line, if found in DT aliases */
|
||
|
id = of_alias_get_id(np, "serial");
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||
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if (id >= 0)
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p->line = id;
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|
#ifdef CONFIG_64BIT
|
||
|
if (of_device_is_compatible(np, "cavium,octeon-3860-uart")) {
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|
p->serial_in = dw8250_serial_inq;
|
||
|
p->serial_out = dw8250_serial_outq;
|
||
|
p->flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_FIXED_TYPE;
|
||
|
p->type = PORT_OCTEON;
|
||
|
data->usr_reg = 0x27;
|
||
|
data->skip_autocfg = true;
|
||
|
}
|
||
|
#endif
|
||
|
if (of_device_is_big_endian(p->dev->of_node)) {
|
||
|
p->iotype = UPIO_MEM32BE;
|
||
|
p->serial_in = dw8250_serial_in32be;
|
||
|
p->serial_out = dw8250_serial_out32be;
|
||
|
}
|
||
|
if (of_device_is_compatible(np, "marvell,armada-38x-uart"))
|
||
|
p->serial_out = dw8250_serial_out38x;
|
||
|
|
||
|
} else if (acpi_dev_present("APMC0D08", NULL, -1)) {
|
||
|
p->iotype = UPIO_MEM32;
|
||
|
p->regshift = 2;
|
||
|
p->serial_in = dw8250_serial_in32;
|
||
|
data->uart_16550_compatible = true;
|
||
|
}
|
||
|
|
||
|
/* Platforms with iDMA 64-bit */
|
||
|
if (platform_get_resource_byname(to_platform_device(p->dev),
|
||
|
IORESOURCE_MEM, "lpss_priv")) {
|
||
|
data->dma.rx_param = p->dev->parent;
|
||
|
data->dma.tx_param = p->dev->parent;
|
||
|
data->dma.fn = dw8250_idma_filter;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
static void dw8250_setup_port(struct uart_port *p)
|
||
|
{
|
||
|
struct uart_8250_port *up = up_to_u8250p(p);
|
||
|
u32 reg;
|
||
|
|
||
|
/*
|
||
|
* If the Component Version Register returns zero, we know that
|
||
|
* ADDITIONAL_FEATURES are not enabled. No need to go any further.
|
||
|
*/
|
||
|
reg = dw8250_readl_ext(p, DW_UART_UCV);
|
||
|
if (!reg)
|
||
|
return;
|
||
|
|
||
|
dev_dbg(p->dev, "Designware UART version %c.%c%c\n",
|
||
|
(reg >> 24) & 0xff, (reg >> 16) & 0xff, (reg >> 8) & 0xff);
|
||
|
|
||
|
dw8250_writel_ext(p, DW_UART_DLF, ~0U);
|
||
|
reg = dw8250_readl_ext(p, DW_UART_DLF);
|
||
|
dw8250_writel_ext(p, DW_UART_DLF, 0);
|
||
|
|
||
|
if (reg) {
|
||
|
struct dw8250_data *d = p->private_data;
|
||
|
|
||
|
d->dlf_size = fls(reg);
|
||
|
p->get_divisor = dw8250_get_divisor;
|
||
|
p->set_divisor = dw8250_set_divisor;
|
||
|
}
|
||
|
|
||
|
reg = dw8250_readl_ext(p, DW_UART_CPR);
|
||
|
if (!reg)
|
||
|
return;
|
||
|
|
||
|
/* Select the type based on fifo */
|
||
|
if (reg & DW_UART_CPR_FIFO_MODE) {
|
||
|
p->type = PORT_16550A;
|
||
|
p->flags |= UPF_FIXED_TYPE;
|
||
|
p->fifosize = DW_UART_CPR_FIFO_SIZE(reg);
|
||
|
up->capabilities = UART_CAP_FIFO;
|
||
|
}
|
||
|
|
||
|
if (reg & DW_UART_CPR_AFCE_MODE)
|
||
|
up->capabilities |= UART_CAP_AFE;
|
||
|
|
||
|
if (reg & DW_UART_CPR_SIR_MODE)
|
||
|
up->capabilities |= UART_CAP_IRDA;
|
||
|
}
|
||
|
|
||
|
static int dw8250_probe(struct platform_device *pdev)
|
||
|
{
|
||
|
struct uart_8250_port uart = {};
|
||
|
struct resource *regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
||
|
int irq = platform_get_irq(pdev, 0);
|
||
|
struct uart_port *p = &uart.port;
|
||
|
struct device *dev = &pdev->dev;
|
||
|
struct dw8250_data *data;
|
||
|
int err;
|
||
|
u32 val;
|
||
|
|
||
|
if (!regs) {
|
||
|
dev_err(dev, "no registers defined\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
if (irq < 0) {
|
||
|
if (irq != -EPROBE_DEFER)
|
||
|
dev_err(dev, "cannot get irq\n");
|
||
|
return irq;
|
||
|
}
|
||
|
|
||
|
spin_lock_init(&p->lock);
|
||
|
p->mapbase = regs->start;
|
||
|
p->irq = irq;
|
||
|
p->handle_irq = dw8250_handle_irq;
|
||
|
p->pm = dw8250_do_pm;
|
||
|
p->type = PORT_8250;
|
||
|
p->flags = UPF_SHARE_IRQ | UPF_FIXED_PORT;
|
||
|
p->dev = dev;
|
||
|
p->iotype = UPIO_MEM;
|
||
|
p->serial_in = dw8250_serial_in;
|
||
|
p->serial_out = dw8250_serial_out;
|
||
|
p->set_ldisc = dw8250_set_ldisc;
|
||
|
p->set_termios = dw8250_set_termios;
|
||
|
|
||
|
p->membase = devm_ioremap(dev, regs->start, resource_size(regs));
|
||
|
if (!p->membase)
|
||
|
return -ENOMEM;
|
||
|
|
||
|
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
|
||
|
if (!data)
|
||
|
return -ENOMEM;
|
||
|
|
||
|
data->dma.fn = dw8250_fallback_dma_filter;
|
||
|
data->usr_reg = DW_UART_USR;
|
||
|
p->private_data = data;
|
||
|
|
||
|
data->uart_16550_compatible = device_property_read_bool(dev,
|
||
|
"snps,uart-16550-compatible");
|
||
|
|
||
|
err = device_property_read_u32(dev, "reg-shift", &val);
|
||
|
if (!err)
|
||
|
p->regshift = val;
|
||
|
|
||
|
err = device_property_read_u32(dev, "reg-io-width", &val);
|
||
|
if (!err && val == 4) {
|
||
|
p->iotype = UPIO_MEM32;
|
||
|
p->serial_in = dw8250_serial_in32;
|
||
|
p->serial_out = dw8250_serial_out32;
|
||
|
}
|
||
|
|
||
|
if (device_property_read_bool(dev, "dcd-override")) {
|
||
|
/* Always report DCD as active */
|
||
|
data->msr_mask_on |= UART_MSR_DCD;
|
||
|
data->msr_mask_off |= UART_MSR_DDCD;
|
||
|
}
|
||
|
|
||
|
if (device_property_read_bool(dev, "dsr-override")) {
|
||
|
/* Always report DSR as active */
|
||
|
data->msr_mask_on |= UART_MSR_DSR;
|
||
|
data->msr_mask_off |= UART_MSR_DDSR;
|
||
|
}
|
||
|
|
||
|
if (device_property_read_bool(dev, "cts-override")) {
|
||
|
/* Always report CTS as active */
|
||
|
data->msr_mask_on |= UART_MSR_CTS;
|
||
|
data->msr_mask_off |= UART_MSR_DCTS;
|
||
|
}
|
||
|
|
||
|
if (device_property_read_bool(dev, "ri-override")) {
|
||
|
/* Always report Ring indicator as inactive */
|
||
|
data->msr_mask_off |= UART_MSR_RI;
|
||
|
data->msr_mask_off |= UART_MSR_TERI;
|
||
|
}
|
||
|
|
||
|
/* Always ask for fixed clock rate from a property. */
|
||
|
device_property_read_u32(dev, "clock-frequency", &p->uartclk);
|
||
|
|
||
|
/* If there is separate baudclk, get the rate from it. */
|
||
|
data->clk = devm_clk_get(dev, "baudclk");
|
||
|
if (IS_ERR(data->clk) && PTR_ERR(data->clk) != -EPROBE_DEFER)
|
||
|
data->clk = devm_clk_get(dev, NULL);
|
||
|
if (IS_ERR(data->clk) && PTR_ERR(data->clk) == -EPROBE_DEFER)
|
||
|
return -EPROBE_DEFER;
|
||
|
if (!IS_ERR_OR_NULL(data->clk)) {
|
||
|
err = clk_prepare_enable(data->clk);
|
||
|
if (err)
|
||
|
dev_warn(dev, "could not enable optional baudclk: %d\n",
|
||
|
err);
|
||
|
else
|
||
|
p->uartclk = clk_get_rate(data->clk);
|
||
|
}
|
||
|
|
||
|
/* If no clock rate is defined, fail. */
|
||
|
if (!p->uartclk) {
|
||
|
dev_err(dev, "clock rate not defined\n");
|
||
|
err = -EINVAL;
|
||
|
goto err_clk;
|
||
|
}
|
||
|
|
||
|
data->pclk = devm_clk_get(dev, "apb_pclk");
|
||
|
if (IS_ERR(data->pclk) && PTR_ERR(data->pclk) == -EPROBE_DEFER) {
|
||
|
err = -EPROBE_DEFER;
|
||
|
goto err_clk;
|
||
|
}
|
||
|
if (!IS_ERR(data->pclk)) {
|
||
|
err = clk_prepare_enable(data->pclk);
|
||
|
if (err) {
|
||
|
dev_err(dev, "could not enable apb_pclk\n");
|
||
|
goto err_clk;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
data->rst = devm_reset_control_get_optional_exclusive(dev, NULL);
|
||
|
if (IS_ERR(data->rst)) {
|
||
|
err = PTR_ERR(data->rst);
|
||
|
goto err_pclk;
|
||
|
}
|
||
|
reset_control_deassert(data->rst);
|
||
|
|
||
|
dw8250_quirks(p, data);
|
||
|
|
||
|
/* If the Busy Functionality is not implemented, don't handle it */
|
||
|
if (data->uart_16550_compatible)
|
||
|
p->handle_irq = NULL;
|
||
|
|
||
|
if (!data->skip_autocfg)
|
||
|
dw8250_setup_port(p);
|
||
|
|
||
|
/* If we have a valid fifosize, try hooking up DMA */
|
||
|
if (p->fifosize) {
|
||
|
data->dma.rxconf.src_maxburst = p->fifosize / 4;
|
||
|
data->dma.txconf.dst_maxburst = p->fifosize / 4;
|
||
|
uart.dma = &data->dma;
|
||
|
}
|
||
|
|
||
|
data->line = serial8250_register_8250_port(&uart);
|
||
|
if (data->line < 0) {
|
||
|
err = data->line;
|
||
|
goto err_reset;
|
||
|
}
|
||
|
|
||
|
platform_set_drvdata(pdev, data);
|
||
|
|
||
|
pm_runtime_set_active(dev);
|
||
|
pm_runtime_enable(dev);
|
||
|
|
||
|
return 0;
|
||
|
|
||
|
err_reset:
|
||
|
reset_control_assert(data->rst);
|
||
|
|
||
|
err_pclk:
|
||
|
if (!IS_ERR(data->pclk))
|
||
|
clk_disable_unprepare(data->pclk);
|
||
|
|
||
|
err_clk:
|
||
|
if (!IS_ERR(data->clk))
|
||
|
clk_disable_unprepare(data->clk);
|
||
|
|
||
|
return err;
|
||
|
}
|
||
|
|
||
|
static int dw8250_remove(struct platform_device *pdev)
|
||
|
{
|
||
|
struct dw8250_data *data = platform_get_drvdata(pdev);
|
||
|
|
||
|
pm_runtime_get_sync(&pdev->dev);
|
||
|
|
||
|
serial8250_unregister_port(data->line);
|
||
|
|
||
|
reset_control_assert(data->rst);
|
||
|
|
||
|
if (!IS_ERR(data->pclk))
|
||
|
clk_disable_unprepare(data->pclk);
|
||
|
|
||
|
if (!IS_ERR(data->clk))
|
||
|
clk_disable_unprepare(data->clk);
|
||
|
|
||
|
pm_runtime_disable(&pdev->dev);
|
||
|
pm_runtime_put_noidle(&pdev->dev);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
#ifdef CONFIG_PM_SLEEP
|
||
|
static int dw8250_suspend(struct device *dev)
|
||
|
{
|
||
|
struct dw8250_data *data = dev_get_drvdata(dev);
|
||
|
|
||
|
serial8250_suspend_port(data->line);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int dw8250_resume(struct device *dev)
|
||
|
{
|
||
|
struct dw8250_data *data = dev_get_drvdata(dev);
|
||
|
|
||
|
serial8250_resume_port(data->line);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
#endif /* CONFIG_PM_SLEEP */
|
||
|
|
||
|
#ifdef CONFIG_PM
|
||
|
static int dw8250_runtime_suspend(struct device *dev)
|
||
|
{
|
||
|
struct dw8250_data *data = dev_get_drvdata(dev);
|
||
|
|
||
|
if (!IS_ERR(data->clk))
|
||
|
clk_disable_unprepare(data->clk);
|
||
|
|
||
|
if (!IS_ERR(data->pclk))
|
||
|
clk_disable_unprepare(data->pclk);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int dw8250_runtime_resume(struct device *dev)
|
||
|
{
|
||
|
struct dw8250_data *data = dev_get_drvdata(dev);
|
||
|
|
||
|
if (!IS_ERR(data->pclk))
|
||
|
clk_prepare_enable(data->pclk);
|
||
|
|
||
|
if (!IS_ERR(data->clk))
|
||
|
clk_prepare_enable(data->clk);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
#endif
|
||
|
|
||
|
static const struct dev_pm_ops dw8250_pm_ops = {
|
||
|
SET_SYSTEM_SLEEP_PM_OPS(dw8250_suspend, dw8250_resume)
|
||
|
SET_RUNTIME_PM_OPS(dw8250_runtime_suspend, dw8250_runtime_resume, NULL)
|
||
|
};
|
||
|
|
||
|
static const struct of_device_id dw8250_of_match[] = {
|
||
|
{ .compatible = "snps,dw-apb-uart" },
|
||
|
{ .compatible = "cavium,octeon-3860-uart" },
|
||
|
{ .compatible = "marvell,armada-38x-uart" },
|
||
|
{ .compatible = "renesas,rzn1-uart" },
|
||
|
{ /* Sentinel */ }
|
||
|
};
|
||
|
MODULE_DEVICE_TABLE(of, dw8250_of_match);
|
||
|
|
||
|
static const struct acpi_device_id dw8250_acpi_match[] = {
|
||
|
{ "INT33C4", 0 },
|
||
|
{ "INT33C5", 0 },
|
||
|
{ "INT3434", 0 },
|
||
|
{ "INT3435", 0 },
|
||
|
{ "80860F0A", 0 },
|
||
|
{ "8086228A", 0 },
|
||
|
{ "APMC0D08", 0},
|
||
|
{ "AMD0020", 0 },
|
||
|
{ "AMDI0020", 0 },
|
||
|
{ "BRCM2032", 0 },
|
||
|
{ "HISI0031", 0 },
|
||
|
{ },
|
||
|
};
|
||
|
MODULE_DEVICE_TABLE(acpi, dw8250_acpi_match);
|
||
|
|
||
|
static struct platform_driver dw8250_platform_driver = {
|
||
|
.driver = {
|
||
|
.name = "dw-apb-uart",
|
||
|
.pm = &dw8250_pm_ops,
|
||
|
.of_match_table = dw8250_of_match,
|
||
|
.acpi_match_table = ACPI_PTR(dw8250_acpi_match),
|
||
|
},
|
||
|
.probe = dw8250_probe,
|
||
|
.remove = dw8250_remove,
|
||
|
};
|
||
|
|
||
|
module_platform_driver(dw8250_platform_driver);
|
||
|
|
||
|
MODULE_AUTHOR("Jamie Iles");
|
||
|
MODULE_LICENSE("GPL");
|
||
|
MODULE_DESCRIPTION("Synopsys DesignWare 8250 serial port driver");
|
||
|
MODULE_ALIAS("platform:dw-apb-uart");
|