Add qemu 2.4.0

[kvmfornfv.git] / qemu / roms / u-boot / drivers / twserial / soft_tws.c

diff --git a/qemu/roms/u-boot/drivers/twserial/soft_tws.c b/qemu/roms/u-boot/drivers/twserial/soft_tws.c
new file mode 100644 (file)
index 0000000..d0bf93d
--- /dev/null
+++ b/qemu/roms/u-boot/drivers/twserial/soft_tws.c
@@ -0,0 +1,94 @@
+/*
+ * (C) Copyright 2009
+ * Detlev Zundel, DENX Software Engineering, dzu@denx.de.
+ *
+ * SPDX-License-Identifier:    GPL-2.0+
+ */
+
+#define TWS_IMPLEMENTATION
+#include <common.h>
+
+/*=====================================================================*/
+/*                         Public Functions                            */
+/*=====================================================================*/
+
+/*-----------------------------------------------------------------------
+ * Read bits
+ */
+int tws_read(uchar *buffer, int len)
+{
+       int rem = len;
+       uchar accu, shift;
+
+       debug("tws_read: buffer %p len %d\n", buffer, len);
+
+       /* Configure the data pin for input */
+       tws_data_config_output(0);
+
+       /* Disable WR, i.e. setup a read */
+       tws_wr(0);
+       udelay(1);
+
+       /* Rise CE */
+       tws_ce(1);
+       udelay(1);
+
+       for (; rem > 0; ) {
+               for (shift = 0, accu = 0;
+                    (rem > 0) && (shift < 8);
+                    rem--, shift++) {
+                       tws_clk(1);
+                       udelay(10);
+                       accu |= (tws_data_read() << shift); /* LSB first */
+                       tws_clk(0);
+                       udelay(10);
+               }
+               *buffer++ = accu;
+       }
+
+       /* Lower CE */
+       tws_ce(0);
+
+       return len - rem;
+}
+
+
+/*-----------------------------------------------------------------------
+ * Write bits
+ */
+int tws_write(uchar *buffer, int len)
+{
+       int rem = len;
+       uchar accu, shift;
+
+       debug("tws_write: buffer %p len %d\n", buffer, len);
+
+       /* Configure the data pin for output */
+       tws_data_config_output(1);
+
+       /* Enable WR, i.e. setup a write */
+       tws_wr(1);
+       udelay(1);
+
+       /* Rise CE */
+       tws_ce(1);
+       udelay(1);
+
+       for (; rem > 0; ) {
+               for (shift = 0, accu = *buffer++;
+                    (rem > 0) && (shift < 8);
+                    rem--, shift++) {
+                       tws_data(accu & 0x01); /* LSB first */
+                       tws_clk(1);
+                       udelay(10);
+                       tws_clk(0);
+                       udelay(10);
+                       accu >>= 1;
+               }
+       }
+
+       /* Lower CE */
+       tws_ce(0);
+
+       return len - rem;
+}