1 files changed, 400 insertions, 0 deletions
diff --git a/linux-core/nv50_i2c.c b/linux-core/nv50_i2c.c
new file mode 100644
index 00000000..30e317c5
--- /dev/null
+++ b/linux-core/nv50_i2c.c
@@ -0,0 +1,400 @@
+/*
+ * Copyright (C) 2008 Maarten Maathuis.
+ * All Rights Reserved.
+ *
+ * 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 (including the
+ * next paragraph) 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 COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS 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 largely a clone from xorg i2c functions, as i had serious trouble getting an i2c_bit_algo adaptor running. */
+
+#include "nv50_i2c.h"
+
+static uint32_t nv50_i2c_port(int index)
+{
+	uint32_t port = 0;
+
+	switch (index) {
+		case 0:
+			port = NV50_PCONNECTOR_I2C_PORT_0;
+			break;
+		case 1:
+			port = NV50_PCONNECTOR_I2C_PORT_1;
+			break;
+		case 2:
+			port = NV50_PCONNECTOR_I2C_PORT_2;
+			break;
+		case 3:
+			port = NV50_PCONNECTOR_I2C_PORT_3;
+			break;
+		case 4:
+			port = NV50_PCONNECTOR_I2C_PORT_4;
+			break;
+		case 5:
+			port = NV50_PCONNECTOR_I2C_PORT_5;
+			break;
+		default:
+			break;
+	}
+
+	if (!port) {
+		DRM_ERROR("Invalid i2c port, returning 0.\n");
+		BUG();
+	}
+
+	return port;
+}
+
+static void nv50_i2c_set_bits(struct nv50_i2c_channel *chan, int clock_high, int data_high)
+{
+	struct drm_nouveau_private *dev_priv = chan->dev->dev_private;
+	uint32_t port = nv50_i2c_port(chan->index);
+
+	if (!port)
+		return;
+
+	NV_WRITE(port, 4 | (data_high << 1) | clock_high);
+}
+
+static void nv50_i2c_get_bits(struct nv50_i2c_channel *chan, int *clock_high, int *data_high)
+{
+	struct drm_nouveau_private *dev_priv = chan->dev->dev_private;
+	uint32_t port = nv50_i2c_port(chan->index);
+	uint32_t val;
+
+	if (!port)
+		return;
+
+	val = NV_READ(port);
+
+	if (val & 1)
+		*clock_high = 1;
+	else
+		*clock_high = 0;
+
+	if (val & 2)
+		*data_high = 1;
+	else
+		*data_high = 0;
+}
+
+static bool nv50_i2c_raise_clock(struct nv50_i2c_channel *chan, int data)
+{
+	int i, clock;
+
+	nv50_i2c_set_bits(chan, 1, data);
+	udelay(2);
+
+	for (i = 2200; i > 0; i -= 2) {
+		nv50_i2c_get_bits(chan, &clock, &data);
+		if (clock)
+			return true;
+		udelay(2);
+	}
+
+	printk("a timeout occured in nv50_i2c_raise_clock\n");
+
+	return false;
+}
+
+static bool nv50_i2c_start(struct nv50_i2c_channel *chan)
+{
+	if (!nv50_i2c_raise_clock(chan, 1))
+		return false;
+
+	nv50_i2c_set_bits(chan, 1, 0);
+	udelay(5);
+
+	nv50_i2c_set_bits(chan, 0, 0);
+	udelay(5);
+
+	return true;
+}
+
+static void nv50_i2c_stop(struct nv50_i2c_channel *chan)
+{
+	nv50_i2c_set_bits(chan, 0, 0);
+	udelay(2);
+
+	nv50_i2c_set_bits(chan, 1, 0);
+	udelay(5);
+
+	nv50_i2c_set_bits(chan, 1, 1);
+	udelay(5);
+}
+
+static bool nv50_i2c_write_bit(struct nv50_i2c_channel *chan, int data)
+{
+	bool rval;
+
+	nv50_i2c_set_bits(chan, 0, data);
+	udelay(2);
+
+	rval = nv50_i2c_raise_clock(chan, data);
+	udelay(5);
+
+	nv50_i2c_set_bits(chan, 0, data);
+	udelay(5);
+
+	return rval;
+}
+
+static bool nv50_i2c_read_bit(struct nv50_i2c_channel *chan, int *data)
+{
+	bool rval;
+	int clock;
+
+	rval = nv50_i2c_raise_clock(chan, 1);
+	udelay(5);
+
+	nv50_i2c_get_bits(chan, &clock, data);
+	udelay(5);
+
+	nv50_i2c_set_bits(chan, 0, 1);
+	udelay(5);
+
+	return rval;
+}
+
+static bool nv50_i2c_write_byte(struct nv50_i2c_channel *chan, uint8_t byte)
+{
+	bool rval;
+	int i, clock, data;
+
+	for (i = 7; i >= 0; i--)
+		if (!nv50_i2c_write_bit(chan, (byte >> i) & 1))
+			return false;
+
+	nv50_i2c_set_bits(chan, 0, 1);
+	udelay(5);
+
+	rval = nv50_i2c_raise_clock(chan, 1);
+
+	if (rval) {
+		for (i = 40; i > 0; i -= 2) {
+			udelay(2);
+			nv50_i2c_get_bits(chan, &clock, &data);
+			if (data == 0) 
+				break;
+		}
+
+		if (i <= 0) {
+			printk("a timeout occured in nv50_i2c_write_byte\n");
+			rval = false;
+		}
+	}
+
+	nv50_i2c_set_bits(chan, 0, 1);
+	udelay(5);
+
+	return rval;
+}
+
+static bool nv50_i2c_read_byte(struct nv50_i2c_channel *chan, uint8_t *byte, bool last)
+{
+	int i, bit;
+
+	nv50_i2c_set_bits(chan, 0, 1);
+	udelay(5);
+
+	*byte = 0;
+
+	for (i = 7; i >= 0; i--) {
+		if (nv50_i2c_read_bit(chan, &bit)) {
+			if (bit)
+				*byte |= (1 << i);
+		} else {
+			return false;
+		}
+	}
+
+	if (!nv50_i2c_write_bit(chan, last ? 1 : 0))
+		return false;
+
+	return true;
+}
+
+/* only 7 bits addresses. */
+static bool nv50_i2c_address(struct nv50_i2c_channel *chan, uint8_t address, bool write)
+{
+	if (nv50_i2c_start(chan)) {
+		uint8_t real_addr = (address << 1);
+		if (!write)
+			real_addr |= 1;
+
+		if (nv50_i2c_write_byte(chan, real_addr))
+			return true;
+
+		/* failure, so issue stop */
+		nv50_i2c_stop(chan);
+	}
+
+	return false;
+}
+
+static bool nv50_i2c_read(struct nv50_i2c_channel *chan, uint8_t address, uint8_t *buffer, uint32_t length)
+{
+	int i, j;
+	bool rval, last;
+
+	/* retries */
+	for (i = 0; i < 4; i++) {
+		rval = nv50_i2c_address(chan, address, false);
+		if (!rval)
+			return false;
+
+		for (j = 0; j < length; j++) {
+			last = false;
+			if (j == (length - 1))
+				last = true;
+			rval = nv50_i2c_read_byte(chan, &buffer[j], last);
+			if (!rval) {
+				nv50_i2c_stop(chan);
+				break;
+			}
+		}
+
+		nv50_i2c_stop(chan);
+
+		/* done */
+		if (rval)
+			break;
+	}
+
+	if (!rval)
+		printk("nv50_i2c_read failed\n");
+
+	return rval;
+}
+
+static bool nv50_i2c_write(struct nv50_i2c_channel *chan, uint8_t address, uint8_t *buffer, uint32_t length)
+{
+	int i, j;
+	bool rval;
+
+	/* retries */
+	for (i = 0; i < 4; i++) {
+		rval = nv50_i2c_address(chan, address, true);
+		if (!rval)
+			return false;
+
+		for (j = 0; j < length; j++) {
+			rval = nv50_i2c_write_byte(chan, buffer[j]);
+			if (!rval) {
+				break;
+			}
+		}
+
+		nv50_i2c_stop(chan);
+
+		/* done */
+		if (rval)
+			break;
+	}
+
+	if (!rval)
+		printk("nv50_i2c_write failed\n");
+
+	return rval;
+}
+
+static int nv50_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
+{
+	struct nv50_i2c_channel *chan = i2c_get_adapdata(i2c_adap);
+	bool rval;
+	int i;
+
+	for (i = 0; i < num; i++) {
+		if (msgs[i].flags & I2C_M_RD) { /* read */
+			rval = nv50_i2c_read(chan, msgs[i].addr, msgs[i].buf, msgs[i].len);
+		} else { /* write */
+			rval = nv50_i2c_write(chan, msgs[i].addr, msgs[i].buf, msgs[i].len);
+		}
+
+		if (!rval)
+			break;
+	}
+
+	if (rval)
+		return i;
+	else
+		return -EINVAL;
+}
+
+static u32 nv50_i2c_functionality(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C;
+}
+
+static const struct i2c_algorithm nv50_i2c_algo = {
+	.master_xfer	= nv50_i2c_xfer,
+	.functionality	= nv50_i2c_functionality,
+};
+
+static int nv50_i2c_register_bus(struct i2c_adapter *adap)
+{
+	adap->algo = &nv50_i2c_algo;
+
+	adap->timeout = 40;
+	adap->retries = 4;
+
+	return i2c_add_adapter(adap);
+}
+
+#define I2C_HW_B_NOUVEAU 0x010030
+struct nv50_i2c_channel *nv50_i2c_channel_create(struct drm_device *dev, uint32_t index)
+{
+	struct nv50_i2c_channel *chan;
+
+	chan = kzalloc(sizeof(struct nv50_i2c_channel), GFP_KERNEL);
+
+	if (!chan)
+		goto out;
+
+	DRM_INFO("Creating i2c bus with index %d\n", index);
+
+	chan->dev = dev;
+	chan->index = index;
+	snprintf(chan->adapter.name, I2C_NAME_SIZE, "nv50 i2c %d", index);
+	chan->adapter.owner = THIS_MODULE;
+	chan->adapter.id = I2C_HW_B_NOUVEAU;
+	chan->adapter.dev.parent = &dev->pdev->dev;
+
+	i2c_set_adapdata(&chan->adapter, chan);
+
+	if (nv50_i2c_register_bus(&chan->adapter))
+		goto out;
+
+	return chan;
+
+out:
+	kfree(chan);
+	return NULL;
+}
+
+void nv50_i2c_channel_destroy(struct nv50_i2c_channel *chan)
+{
+	if (!chan)
+		return;
+
+	i2c_del_adapter(&chan->adapter);
+	kfree(chan);
+}