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-rw-r--r--drivers/ps2ser.c166
1 files changed, 166 insertions, 0 deletions
diff --git a/drivers/ps2ser.c b/drivers/ps2ser.c
new file mode 100644
index 0000000..71658d7
--- /dev/null
+++ b/drivers/ps2ser.c
@@ -0,0 +1,166 @@
+/***********************************************************************
+ *
+ * (C) Copyright 2004
+ * DENX Software Engineering
+ * Wolfgang Denk, wd@denx.de
+ * All rights reserved.
+ *
+ * Simple 16550A serial driver
+ *
+ * Originally from linux source (drivers/char/ps2ser.c)
+ *
+ * Used by the PS/2 multiplexer driver (ps2mult.c)
+ *
+ ***********************************************************************/
+
+#include <common.h>
+
+#ifdef CONFIG_PS2SERIAL
+
+#include <asm/io.h>
+#include <asm/atomic.h>
+#include <ps2mult.h>
+
+/* #define DEBUG */
+
+#define PS2SER_BAUD 57600
+
+static int ps2ser_getc_hw(void);
+static void ps2ser_interrupt(void *dev_id);
+
+extern struct serial_state rs_table[]; /* in serial.c */
+static struct serial_state *state = rs_table + CONFIG_PS2SERIAL;
+
+static u_char ps2buf[PS2BUF_SIZE];
+static atomic_t ps2buf_cnt;
+static int ps2buf_in_idx;
+static int ps2buf_out_idx;
+
+
+static inline unsigned int ps2ser_in(int offset)
+{
+ return readb((unsigned long) state->iomem_base + offset);
+}
+
+static inline void ps2ser_out(int offset, int value)
+{
+ writeb(value, (unsigned long) state->iomem_base + offset);
+}
+
+int ps2ser_init(void)
+{
+ int quot = state->baud_base / PS2SER_BAUD;
+ unsigned cval = 0x3; /* 8N1 - 8 data bits, no parity bits, 1 stop bit */
+
+ /* Set speed, enable interrupts, enable FIFO
+ */
+ ps2ser_out(UART_LCR, cval | UART_LCR_DLAB);
+ ps2ser_out(UART_DLL, quot & 0xff);
+ ps2ser_out(UART_DLM, quot >> 8);
+ ps2ser_out(UART_LCR, cval);
+ ps2ser_out(UART_IER, UART_IER_RDI);
+ ps2ser_out(UART_MCR, UART_MCR_OUT2 | UART_MCR_DTR | UART_MCR_RTS);
+ ps2ser_out(UART_FCR,
+ UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
+
+ /* If we read 0xff from the LSR, there is no UART here
+ */
+ if (ps2ser_in(UART_LSR) == 0xff) {
+ printf ("ps2ser.c: no UART found\n");
+ return -1;
+ }
+
+ irq_install_handler(state->irq, ps2ser_interrupt, NULL);
+
+ return 0;
+}
+
+void ps2ser_putc(int chr)
+{
+#ifdef DEBUG
+ printf(">>>> 0x%02x\n", chr);
+#endif
+
+ while (!(ps2ser_in(UART_LSR) & UART_LSR_THRE));
+
+ ps2ser_out(UART_TX, chr);
+}
+
+static int ps2ser_getc_hw(void)
+{
+ int res = -1;
+
+ if (ps2ser_in(UART_LSR) & UART_LSR_DR) {
+ res = (ps2ser_in(UART_RX));
+ }
+
+ return res;
+}
+
+int ps2ser_getc(void)
+{
+ volatile int chr;
+ int flags;
+
+#ifdef DEBUG
+ printf("<< ");
+#endif
+
+ flags = disable_interrupts();
+
+ do {
+ if (atomic_read(&ps2buf_cnt) != 0) {
+ chr = ps2buf[ps2buf_out_idx++];
+ ps2buf_out_idx &= (PS2BUF_SIZE - 1);
+ atomic_dec(&ps2buf_cnt);
+ } else {
+ chr = ps2ser_getc_hw();
+ }
+ }
+ while (chr < 0);
+
+ if (flags) enable_interrupts();
+
+#ifdef DEBUG
+ printf("0x%02x\n", chr);
+#endif
+
+ return chr;
+}
+
+int ps2ser_check(void)
+{
+ int flags;
+
+ flags = disable_interrupts();
+ ps2ser_interrupt(NULL);
+ if (flags) enable_interrupts();
+
+ return atomic_read(&ps2buf_cnt);
+}
+
+static void ps2ser_interrupt(void *dev_id)
+{
+ int chr;
+ int iir;
+
+ do {
+ chr = ps2ser_getc_hw();
+ iir = ps2ser_in(UART_IIR);
+ if (chr < 0) continue;
+
+ if (atomic_read(&ps2buf_cnt) < PS2BUF_SIZE) {
+ ps2buf[ps2buf_in_idx++] = chr;
+ ps2buf_in_idx &= (PS2BUF_SIZE - 1);
+ atomic_inc(&ps2buf_cnt);
+ } else {
+ printf ("ps2ser.c: buffer overflow\n");
+ }
+ } while (iir & UART_IIR_RDI);
+
+ if (atomic_read(&ps2buf_cnt)) {
+ ps2mult_callback(atomic_read(&ps2buf_cnt));
+ }
+}
+
+#endif /* CONFIG_PS2SERIAL */