+++ /dev/null
-/*
- * Synopsys DesignWare specific 8250 operations.
- *
- * Copyright 2011 Picochip, Jamie Iles.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * The Synopsys DesignWare 8250 has an extra feature whereby it detects if the
- * LCR is written whilst busy. If it is, then a busy detect interrupt is
- * raised, the LCR needs to be rewritten and the uart status register read.
- */
-#include <linux/io.h>
-#include <linux/serial_8250.h>
-#include <linux/serial_core.h>
-#include <linux/serial_reg.h>
-#include <linux/slab.h>
-
-struct dw8250_data {
- int last_lcr;
-};
-
-static void dw8250_serial_out(struct uart_port *p, int offset, int value)
-{
- struct dw8250_data *d = p->private_data;
-
- if (offset == UART_LCR)
- d->last_lcr = value;
-
- offset <<= p->regshift;
- writeb(value, p->membase + offset);
-}
-
-static unsigned int dw8250_serial_in(struct uart_port *p, int offset)
-{
- offset <<= p->regshift;
-
- return readb(p->membase + offset);
-}
-
-static void dw8250_serial_out32(struct uart_port *p, int offset,
- int value)
-{
- struct dw8250_data *d = p->private_data;
-
- if (offset == UART_LCR)
- d->last_lcr = value;
-
- offset <<= p->regshift;
- writel(value, p->membase + offset);
-}
-
-static unsigned int dw8250_serial_in32(struct uart_port *p, int offset)
-{
- offset <<= p->regshift;
-
- return readl(p->membase + offset);
-}
-
-/* Offset for the DesignWare's UART Status Register. */
-#define UART_USR 0x1f
-
-static int dw8250_handle_irq(struct uart_port *p)
-{
- struct dw8250_data *d = p->private_data;
- unsigned int iir = p->serial_in(p, UART_IIR);
-
- if (serial8250_handle_irq(p, iir)) {
- return 1;
- } else if ((iir & UART_IIR_BUSY) == UART_IIR_BUSY) {
- /* Clear the USR and write the LCR again. */
- (void)p->serial_in(p, UART_USR);
- p->serial_out(p, d->last_lcr, UART_LCR);
-
- return 1;
- }
-
- return 0;
-}
-
-int serial8250_use_designware_io(struct uart_port *up)
-{
- up->private_data = kzalloc(sizeof(struct dw8250_data), GFP_KERNEL);
- if (!up->private_data)
- return -ENOMEM;
-
- if (up->iotype == UPIO_MEM32) {
- up->serial_out = dw8250_serial_out32;
- up->serial_in = dw8250_serial_in32;
- } else {
- up->serial_out = dw8250_serial_out;
- up->serial_in = dw8250_serial_in;
- }
- up->handle_irq = dw8250_handle_irq;
-
- return 0;
-}