1 files changed, 405 insertions, 0 deletions
diff --git a/drivers/media/pci/cx25821/cx25821-i2c.c b/drivers/media/pci/cx25821/cx25821-i2c.c
new file mode 100644
index 000000000..0ef4cd652
--- /dev/null
+++ b/drivers/media/pci/cx25821/cx25821-i2c.c
@@ -0,0 +1,405 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  Driver for the Conexant CX25821 PCIe bridge
+ *
+ *  Copyright (C) 2009 Conexant Systems Inc.
+ *  Authors  <shu.lin@conexant.com>, <hiep.huynh@conexant.com>
+ *	Based on Steven Toth <stoth@linuxtv.org> cx23885 driver
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include "cx25821.h"
+
+static unsigned int i2c_debug;
+module_param(i2c_debug, int, 0644);
+MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
+
+static unsigned int i2c_scan;
+module_param(i2c_scan, int, 0444);
+MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time");
+
+#define dprintk(level, fmt, arg...)					\
+do {									\
+	if (i2c_debug >= level)						\
+		printk(KERN_DEBUG "%s/0: " fmt, dev->name, ##arg);	\
+} while (0)
+
+#define I2C_WAIT_DELAY 32
+#define I2C_WAIT_RETRY 64
+
+#define I2C_EXTEND  (1 << 3)
+#define I2C_NOSTOP  (1 << 4)
+
+static inline int i2c_slave_did_ack(struct i2c_adapter *i2c_adap)
+{
+	struct cx25821_i2c *bus = i2c_adap->algo_data;
+	struct cx25821_dev *dev = bus->dev;
+	return cx_read(bus->reg_stat) & 0x01;
+}
+
+static inline int i2c_is_busy(struct i2c_adapter *i2c_adap)
+{
+	struct cx25821_i2c *bus = i2c_adap->algo_data;
+	struct cx25821_dev *dev = bus->dev;
+	return cx_read(bus->reg_stat) & 0x02 ? 1 : 0;
+}
+
+static int i2c_wait_done(struct i2c_adapter *i2c_adap)
+{
+	int count;
+
+	for (count = 0; count < I2C_WAIT_RETRY; count++) {
+		if (!i2c_is_busy(i2c_adap))
+			break;
+		udelay(I2C_WAIT_DELAY);
+	}
+
+	if (I2C_WAIT_RETRY == count)
+		return 0;
+
+	return 1;
+}
+
+static int i2c_sendbytes(struct i2c_adapter *i2c_adap,
+			 const struct i2c_msg *msg, int joined_rlen)
+{
+	struct cx25821_i2c *bus = i2c_adap->algo_data;
+	struct cx25821_dev *dev = bus->dev;
+	u32 wdata, addr, ctrl;
+	int retval, cnt;
+
+	if (joined_rlen)
+		dprintk(1, "%s(msg->wlen=%d, nextmsg->rlen=%d)\n", __func__,
+			msg->len, joined_rlen);
+	else
+		dprintk(1, "%s(msg->len=%d)\n", __func__, msg->len);
+
+	/* Deal with i2c probe functions with zero payload */
+	if (msg->len == 0) {
+		cx_write(bus->reg_addr, msg->addr << 25);
+		cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2));
+
+		if (!i2c_wait_done(i2c_adap))
+			return -EIO;
+
+		if (!i2c_slave_did_ack(i2c_adap))
+			return -EIO;
+
+		dprintk(1, "%s(): returns 0\n", __func__);
+		return 0;
+	}
+
+	/* dev, reg + first byte */
+	addr = (msg->addr << 25) | msg->buf[0];
+	wdata = msg->buf[0];
+
+	ctrl = bus->i2c_period | (1 << 12) | (1 << 2);
+
+	if (msg->len > 1)
+		ctrl |= I2C_NOSTOP | I2C_EXTEND;
+	else if (joined_rlen)
+		ctrl |= I2C_NOSTOP;
+
+	cx_write(bus->reg_addr, addr);
+	cx_write(bus->reg_wdata, wdata);
+	cx_write(bus->reg_ctrl, ctrl);
+
+	retval = i2c_wait_done(i2c_adap);
+	if (retval < 0)
+		goto err;
+
+	if (retval == 0)
+		goto eio;
+
+	if (i2c_debug) {
+		if (!(ctrl & I2C_NOSTOP))
+			printk(" >\n");
+	}
+
+	for (cnt = 1; cnt < msg->len; cnt++) {
+		/* following bytes */
+		wdata = msg->buf[cnt];
+		ctrl = bus->i2c_period | (1 << 12) | (1 << 2);
+
+		if (cnt < msg->len - 1)
+			ctrl |= I2C_NOSTOP | I2C_EXTEND;
+		else if (joined_rlen)
+			ctrl |= I2C_NOSTOP;
+
+		cx_write(bus->reg_addr, addr);
+		cx_write(bus->reg_wdata, wdata);
+		cx_write(bus->reg_ctrl, ctrl);
+
+		retval = i2c_wait_done(i2c_adap);
+		if (retval < 0)
+			goto err;
+
+		if (retval == 0)
+			goto eio;
+
+		if (i2c_debug) {
+			dprintk(1, " %02x", msg->buf[cnt]);
+			if (!(ctrl & I2C_NOSTOP))
+				dprintk(1, " >\n");
+		}
+	}
+
+	return msg->len;
+
+eio:
+	retval = -EIO;
+err:
+	if (i2c_debug)
+		pr_err(" ERR: %d\n", retval);
+	return retval;
+}
+
+static int i2c_readbytes(struct i2c_adapter *i2c_adap,
+			 const struct i2c_msg *msg, int joined)
+{
+	struct cx25821_i2c *bus = i2c_adap->algo_data;
+	struct cx25821_dev *dev = bus->dev;
+	u32 ctrl, cnt;
+	int retval;
+
+	if (i2c_debug && !joined)
+		dprintk(1, "6-%s(msg->len=%d)\n", __func__, msg->len);
+
+	/* Deal with i2c probe functions with zero payload */
+	if (msg->len == 0) {
+		cx_write(bus->reg_addr, msg->addr << 25);
+		cx_write(bus->reg_ctrl, bus->i2c_period | (1 << 2) | 1);
+		if (!i2c_wait_done(i2c_adap))
+			return -EIO;
+		if (!i2c_slave_did_ack(i2c_adap))
+			return -EIO;
+
+		dprintk(1, "%s(): returns 0\n", __func__);
+		return 0;
+	}
+
+	if (i2c_debug) {
+		if (joined)
+			dprintk(1, " R");
+		else
+			dprintk(1, " <R %02x", (msg->addr << 1) + 1);
+	}
+
+	for (cnt = 0; cnt < msg->len; cnt++) {
+
+		ctrl = bus->i2c_period | (1 << 12) | (1 << 2) | 1;
+
+		if (cnt < msg->len - 1)
+			ctrl |= I2C_NOSTOP | I2C_EXTEND;
+
+		cx_write(bus->reg_addr, msg->addr << 25);
+		cx_write(bus->reg_ctrl, ctrl);
+
+		retval = i2c_wait_done(i2c_adap);
+		if (retval < 0)
+			goto err;
+		if (retval == 0)
+			goto eio;
+		msg->buf[cnt] = cx_read(bus->reg_rdata) & 0xff;
+
+		if (i2c_debug) {
+			dprintk(1, " %02x", msg->buf[cnt]);
+			if (!(ctrl & I2C_NOSTOP))
+				dprintk(1, " >\n");
+		}
+	}
+
+	return msg->len;
+eio:
+	retval = -EIO;
+err:
+	if (i2c_debug)
+		pr_err(" ERR: %d\n", retval);
+	return retval;
+}
+
+static int i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
+{
+	struct cx25821_i2c *bus = i2c_adap->algo_data;
+	struct cx25821_dev *dev = bus->dev;
+	int i, retval = 0;
+
+	dprintk(1, "%s(num = %d)\n", __func__, num);
+
+	for (i = 0; i < num; i++) {
+		dprintk(1, "%s(num = %d) addr = 0x%02x  len = 0x%x\n",
+			__func__, num, msgs[i].addr, msgs[i].len);
+
+		if (msgs[i].flags & I2C_M_RD) {
+			/* read */
+			retval = i2c_readbytes(i2c_adap, &msgs[i], 0);
+		} else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
+			   msgs[i].addr == msgs[i + 1].addr) {
+			/* write then read from same address */
+			retval = i2c_sendbytes(i2c_adap, &msgs[i],
+					msgs[i + 1].len);
+
+			if (retval < 0)
+				goto err;
+			i++;
+			retval = i2c_readbytes(i2c_adap, &msgs[i], 1);
+		} else {
+			/* write */
+			retval = i2c_sendbytes(i2c_adap, &msgs[i], 0);
+		}
+
+		if (retval < 0)
+			goto err;
+	}
+	return num;
+
+err:
+	return retval;
+}
+
+
+static u32 cx25821_functionality(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C | I2C_FUNC_SMBUS_WORD_DATA |
+		I2C_FUNC_SMBUS_READ_WORD_DATA | I2C_FUNC_SMBUS_WRITE_WORD_DATA;
+}
+
+static const struct i2c_algorithm cx25821_i2c_algo_template = {
+	.master_xfer = i2c_xfer,
+	.functionality = cx25821_functionality,
+#ifdef NEED_ALGO_CONTROL
+	.algo_control = dummy_algo_control,
+#endif
+};
+
+static const struct i2c_adapter cx25821_i2c_adap_template = {
+	.name = "cx25821",
+	.owner = THIS_MODULE,
+	.algo = &cx25821_i2c_algo_template,
+};
+
+static const struct i2c_client cx25821_i2c_client_template = {
+	.name = "cx25821 internal",
+};
+
+/* init + register i2c adapter */
+int cx25821_i2c_register(struct cx25821_i2c *bus)
+{
+	struct cx25821_dev *dev = bus->dev;
+
+	dprintk(1, "%s(bus = %d)\n", __func__, bus->nr);
+
+	bus->i2c_adap = cx25821_i2c_adap_template;
+	bus->i2c_client = cx25821_i2c_client_template;
+	bus->i2c_adap.dev.parent = &dev->pci->dev;
+
+	strscpy(bus->i2c_adap.name, bus->dev->name, sizeof(bus->i2c_adap.name));
+
+	bus->i2c_adap.algo_data = bus;
+	i2c_set_adapdata(&bus->i2c_adap, &dev->v4l2_dev);
+	i2c_add_adapter(&bus->i2c_adap);
+
+	bus->i2c_client.adapter = &bus->i2c_adap;
+
+	/* set up the I2c */
+	bus->i2c_client.addr = (0x88 >> 1);
+
+	return bus->i2c_rc;
+}
+
+int cx25821_i2c_unregister(struct cx25821_i2c *bus)
+{
+	i2c_del_adapter(&bus->i2c_adap);
+	return 0;
+}
+
+#if 0 /* Currently unused */
+static void cx25821_av_clk(struct cx25821_dev *dev, int enable)
+{
+	/* write 0 to bus 2 addr 0x144 via i2x_xfer() */
+	char buffer[3];
+	struct i2c_msg msg;
+	dprintk(1, "%s(enabled = %d)\n", __func__, enable);
+
+	/* Register 0x144 */
+	buffer[0] = 0x01;
+	buffer[1] = 0x44;
+	if (enable == 1)
+		buffer[2] = 0x05;
+	else
+		buffer[2] = 0x00;
+
+	msg.addr = 0x44;
+	msg.flags = I2C_M_TEN;
+	msg.len = 3;
+	msg.buf = buffer;
+
+	i2c_xfer(&dev->i2c_bus[0].i2c_adap, &msg, 1);
+}
+#endif
+
+int cx25821_i2c_read(struct cx25821_i2c *bus, u16 reg_addr, int *value)
+{
+	struct i2c_client *client = &bus->i2c_client;
+	int v = 0;
+	u8 addr[2] = { 0, 0 };
+	u8 buf[4] = { 0, 0, 0, 0 };
+
+	struct i2c_msg msgs[2] = {
+		{
+			.addr = client->addr,
+			.flags = 0,
+			.len = 2,
+			.buf = addr,
+		}, {
+			.addr = client->addr,
+			.flags = I2C_M_RD,
+			.len = 4,
+			.buf = buf,
+		}
+	};
+
+	addr[0] = (reg_addr >> 8);
+	addr[1] = (reg_addr & 0xff);
+	msgs[0].addr = 0x44;
+	msgs[1].addr = 0x44;
+
+	i2c_xfer(client->adapter, msgs, 2);
+
+	v = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
+	*value = v;
+
+	return v;
+}
+
+int cx25821_i2c_write(struct cx25821_i2c *bus, u16 reg_addr, int value)
+{
+	struct i2c_client *client = &bus->i2c_client;
+	int retval = 0;
+	u8 buf[6] = { 0, 0, 0, 0, 0, 0 };
+
+	struct i2c_msg msgs[1] = {
+		{
+			.addr = client->addr,
+			.flags = 0,
+			.len = 6,
+			.buf = buf,
+		}
+	};
+
+	buf[0] = reg_addr >> 8;
+	buf[1] = reg_addr & 0xff;
+	buf[5] = (value >> 24) & 0xff;
+	buf[4] = (value >> 16) & 0xff;
+	buf[3] = (value >> 8) & 0xff;
+	buf[2] = value & 0xff;
+	client->flags = 0;
+	msgs[0].addr = 0x44;
+
+	retval = i2c_xfer(client->adapter, msgs, 1);
+
+	return retval;
+}