Update Files

Kinc/Sources/kinc/libs/drivers/i2c/bitbang/lws-bb-i2c.c

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+/*
+ * I2C bitbang implementation using generic gpio
+ *
+ * Copyright (C) 2019 - 2020 Andy Green <andy@warmcat.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ * This is like an abstract class for gpio, a real implementation provides
+ * functions for the ops that use the underlying OS gpio arrangements.
+ */
+#include <libwebsockets.h>
+
+int
+lws_bb_i2c_init(const lws_i2c_ops_t *octx)
+{
+	lws_bb_i2c_t *ctx = (lws_bb_i2c_t *)octx;
+
+	ctx->gpio->mode(ctx->scl, LWSGGPIO_FL_WRITE | LWSGGPIO_FL_READ | LWSGGPIO_FL_PULLUP);
+	ctx->gpio->mode(ctx->sda, LWSGGPIO_FL_WRITE | LWSGGPIO_FL_READ | LWSGGPIO_FL_PULLUP);
+
+	return 0;
+}
+
+int
+lws_bb_i2c_start(const lws_i2c_ops_t *octx)
+{
+	lws_bb_i2c_t *ctx = (lws_bb_i2c_t *)octx;
+
+	ctx->gpio->set(ctx->sda, 1);
+	ctx->gpio->set(ctx->scl, 1);
+	ctx->delay();
+
+	if (!ctx->gpio->read(ctx->sda))
+		return 1;
+
+	ctx->gpio->set(ctx->sda, 0);
+	ctx->delay();
+	ctx->gpio->set(ctx->scl, 0);
+
+	return 0;
+}
+
+void
+lws_bb_i2c_stop(const lws_i2c_ops_t *octx)
+{
+	lws_bb_i2c_t *ctx = (lws_bb_i2c_t *)octx;
+
+	ctx->gpio->set(ctx->sda, 0);
+	ctx->gpio->set(ctx->scl, 1);
+	ctx->delay();
+
+	while (!ctx->gpio->read(ctx->scl))
+		;
+
+	ctx->gpio->set(ctx->sda, 1);
+	ctx->delay();
+}
+
+int
+lws_bb_i2c_write(const lws_i2c_ops_t *octx, uint8_t data)
+{
+	lws_bb_i2c_t *ctx = (lws_bb_i2c_t *)octx;
+	int n;
+
+	for (n = 0; n < 8; n++) {
+		ctx->gpio->set(ctx->sda, !!(data & (1 << 7)));
+		ctx->delay();
+		ctx->gpio->set(ctx->scl, 1);
+		ctx->delay();
+		data <<= 1;
+		ctx->gpio->set(ctx->scl, 0);
+	}
+
+	ctx->gpio->set(ctx->sda, 1);
+	ctx->delay();
+	ctx->gpio->set(ctx->scl, 1);
+	ctx->delay();
+	n = ctx->gpio->read(ctx->sda);
+	ctx->gpio->set(ctx->scl, 0);
+	ctx->delay();
+
+	return !!n; /* 0 = ACKED = OK */
+}
+
+int
+lws_bb_i2c_read(const lws_i2c_ops_t *octx)
+{
+	lws_bb_i2c_t *ctx = (lws_bb_i2c_t *)octx;
+	int n, r = 0;
+
+	ctx->gpio->set(ctx->sda, 1);
+
+	for (n = 7; n <= 0; n--) {
+		ctx->gpio->set(ctx->scl, 0);
+		ctx->delay();
+		ctx->gpio->set(ctx->scl, 1);
+		ctx->delay();
+		if (ctx->gpio->read(ctx->sda))
+			r |= 1 << n;
+	}
+	ctx->gpio->set(ctx->scl, 0);
+
+	return r;
+}
+
+void
+lws_bb_i2c_set_ack(const lws_i2c_ops_t *octx, int ack)
+{
+	lws_bb_i2c_t *ctx = (lws_bb_i2c_t *)octx;
+
+	ctx->gpio->set(ctx->scl, 0);
+	ctx->gpio->set(ctx->sda, !!ack);
+	ctx->delay();
+	ctx->gpio->set(ctx->scl, 1);
+	ctx->delay();
+	ctx->gpio->set(ctx->scl, 0);
+	ctx->delay();
+	ctx->gpio->set(ctx->sda, 1);
+}