1 files changed, 425 insertions, 0 deletions

diff --git a/drivers/staging/cx25821/cx25821-i2c.c b/drivers/staging/cx25821/cx25821-i2c.c
new file mode 100644
index 00000000000..130dfebebe2
--- /dev/null
+++ b/drivers/staging/cx25821/cx25821-i2c.c
@@ -0,0 +1,425 @@
+/*
+ *  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
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include "cx25821.h"
+#include <linux/i2c.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 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 struct i2c_adapter cx25821_i2c_adap_template = {
+        .name = "cx25821",
+        .owner = THIS_MODULE,
+        .algo = &cx25821_i2c_algo_template,
+};
+
+static struct i2c_client cx25821_i2c_client_template = {
+        .name = "cx25821 internal",
+};
+
+/* init + register i2c algo-bit adapter */
+int cx25821_i2c_register(struct cx25821_i2c *bus)
+{
+        struct cx25821_dev *dev = bus->dev;
+
+        dprintk(1, "%s(bus = %d)\n", __func__, bus->nr);
+
+        memcpy(&bus->i2c_adap, &cx25821_i2c_adap_template,
+               sizeof(bus->i2c_adap));
+        memcpy(&bus->i2c_algo, &cx25821_i2c_algo_template,
+               sizeof(bus->i2c_algo));
+        memcpy(&bus->i2c_client, &cx25821_i2c_client_template,
+               sizeof(bus->i2c_client));
+
+        bus->i2c_adap.dev.parent = &dev->pci->dev;
+
+        strlcpy(bus->i2c_adap.name, bus->dev->name, sizeof(bus->i2c_adap.name));
+
+        bus->i2c_algo.data = bus;
+        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;
+}
+
+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);
+}
+
+int cx25821_i2c_read(struct cx25821_i2c *bus, u16 reg_addr, int *value)
+{
+        struct i2c_client *client = &bus->i2c_client;
+        int retval = 0;
+        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;
+
+        retval = 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;
+}