struct dw8250_data {
- int last_lcr;
+ int last_mcr;
int line;
struct clk *clk;
};
+static inline int dw8250_modify_msr(struct uart_port *p, int offset, int value)
+{
+ struct dw8250_data *d = p->private_data;
+
+ /* If reading MSR, report CTS asserted when auto-CTS/RTS enabled */
+ if (offset == UART_MSR && d->last_mcr & UART_MCR_AFE) {
+ value |= UART_MSR_CTS;
+ value &= ~UART_MSR_DCTS;
+ }
+
+ return value;
+}
+
+static void dw8250_force_idle(struct uart_port *p)
+{
+ serial8250_clear_and_reinit_fifos(container_of
+ (p, struct uart_8250_port, port));
+ (void)p->serial_in(p, UART_RX);
+}
+
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;
+ if (offset == UART_MCR)
+ d->last_mcr = value;
+
+ writeb(value, p->membase + (offset << p->regshift));
- offset <<= p->regshift;
- writeb(value, p->membase + offset);
+ /* Make sure LCR write wasn't ignored */
+ if (offset == UART_LCR) {
+ int tries = 1000;
+ while (tries--) {
+ unsigned int lcr = p->serial_in(p, UART_LCR);
+ if ((value & ~UART_LCR_SPAR) == (lcr & ~UART_LCR_SPAR))
+ return;
+ dw8250_force_idle(p);
+ writeb(value, p->membase + (UART_LCR << p->regshift));
+ }
+ dev_err(p->dev, "Couldn't set LCR to %d\n", value);
+ }
}
static unsigned int dw8250_serial_in(struct uart_port *p, int offset)
{
- offset <<= p->regshift;
+ unsigned int value = readb(p->membase + (offset << p->regshift));
- return readb(p->membase + offset);
+ return dw8250_modify_msr(p, offset, value);
}
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;
+ if (offset == UART_MCR)
+ d->last_mcr = value;
- offset <<= p->regshift;
- writel(value, p->membase + offset);
+ writel(value, p->membase + (offset << p->regshift));
+
+ /* Make sure LCR write wasn't ignored */
+ if (offset == UART_LCR) {
+ int tries = 1000;
+ while (tries--) {
+ unsigned int lcr = p->serial_in(p, UART_LCR);
+ if ((value & ~UART_LCR_SPAR) == (lcr & ~UART_LCR_SPAR))
+ return;
+ dw8250_force_idle(p);
+ writel(value, p->membase + (UART_LCR << p->regshift));
+ }
+ dev_err(p->dev, "Couldn't set LCR to %d\n", value);
+ }
}
static unsigned int dw8250_serial_in32(struct uart_port *p, int offset)
{
- offset <<= p->regshift;
+ unsigned int value = readl(p->membase + (offset << p->regshift));
- return readl(p->membase + offset);
+ return dw8250_modify_msr(p, offset, value);
}
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. */
+ /* Clear the USR */
(void)p->serial_in(p, DW_UART_USR);
- p->serial_out(p, UART_LCR, d->last_lcr);
return 1;
}