1 files changed, 294 insertions, 0 deletions

diff --git a/drivers/media/video/stk1160/stk1160-i2c.c b/drivers/media/video/stk1160/stk1160-i2c.c
new file mode 100644
index 00000000000..176ac937306
--- /dev/null
+++ b/drivers/media/video/stk1160/stk1160-i2c.c
@@ -0,0 +1,294 @@
+/*
+ * STK1160 driver
+ *
+ * Copyright (C) 2012 Ezequiel Garcia
+ * <elezegarcia--a.t--gmail.com>
+ *
+ * Based on Easycap driver by R.M. Thomas
+ *      Copyright (C) 2010 R.M. Thomas
+ *      <rmthomas--a.t--sciolus.org>
+ *
+ * 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.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/i2c.h>
+
+#include "stk1160.h"
+#include "stk1160-reg.h"
+
+static unsigned int i2c_debug;
+module_param(i2c_debug, int, 0644);
+MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
+
+#define dprintk_i2c(fmt, args...)                               \
+do {                                                            \
+        if (i2c_debug)                                          \
+                printk(KERN_DEBUG fmt, ##args);                 \
+} while (0)
+
+static int stk1160_i2c_busy_wait(struct stk1160 *dev, u8 wait_bit_mask)
+{
+        unsigned long end;
+        u8 flag;
+
+        /* Wait until read/write finish bit is set */
+        end = jiffies + msecs_to_jiffies(STK1160_I2C_TIMEOUT);
+        while (time_is_after_jiffies(end)) {
+
+                stk1160_read_reg(dev, STK1160_SICTL+1, &flag);
+                /* read/write done? */
+                if (flag & wait_bit_mask)
+                        goto done;
+
+                usleep_range(10 * USEC_PER_MSEC, 20 * USEC_PER_MSEC);
+        }
+
+        return -ETIMEDOUT;
+
+done:
+        return 0;
+}
+
+static int stk1160_i2c_write_reg(struct stk1160 *dev, u8 addr,
+                u8 reg, u8 value)
+{
+        int rc;
+
+        /* Set serial device address */
+        rc = stk1160_write_reg(dev, STK1160_SICTL_SDA, addr);
+        if (rc < 0)
+                return rc;
+
+        /* Set i2c device register sub-address */
+        rc = stk1160_write_reg(dev, STK1160_SBUSW_WA, reg);
+        if (rc < 0)
+                return rc;
+
+        /* Set i2c device register value */
+        rc = stk1160_write_reg(dev, STK1160_SBUSW_WD, value);
+        if (rc < 0)
+                return rc;
+
+        /* Start write now */
+        rc = stk1160_write_reg(dev, STK1160_SICTL, 0x01);
+        if (rc < 0)
+                return rc;
+
+        rc = stk1160_i2c_busy_wait(dev, 0x04);
+        if (rc < 0)
+                return rc;
+
+        return 0;
+}
+
+static int stk1160_i2c_read_reg(struct stk1160 *dev, u8 addr,
+                u8 reg, u8 *value)
+{
+        int rc;
+
+        /* Set serial device address */
+        rc = stk1160_write_reg(dev, STK1160_SICTL_SDA, addr);
+        if (rc < 0)
+                return rc;
+
+        /* Set i2c device register sub-address */
+        rc = stk1160_write_reg(dev, STK1160_SBUSR_RA, reg);
+        if (rc < 0)
+                return rc;
+
+        /* Start read now */
+        rc = stk1160_write_reg(dev, STK1160_SICTL, 0x20);
+        if (rc < 0)
+                return rc;
+
+        rc = stk1160_i2c_busy_wait(dev, 0x01);
+        if (rc < 0)
+                return rc;
+
+        stk1160_read_reg(dev, STK1160_SBUSR_RD, value);
+        if (rc < 0)
+                return rc;
+
+        return 0;
+}
+
+/*
+ * stk1160_i2c_check_for_device()
+ * check if there is a i2c_device at the supplied address
+ */
+static int stk1160_i2c_check_for_device(struct stk1160 *dev,
+                unsigned char addr)
+{
+        int rc;
+
+        /* Set serial device address */
+        rc = stk1160_write_reg(dev, STK1160_SICTL_SDA, addr);
+        if (rc < 0)
+                return rc;
+
+        /* Set device sub-address, we'll chip version reg */
+        rc = stk1160_write_reg(dev, STK1160_SBUSR_RA, 0x00);
+        if (rc < 0)
+                return rc;
+
+        /* Start read now */
+        rc = stk1160_write_reg(dev, STK1160_SICTL, 0x20);
+        if (rc < 0)
+                return rc;
+
+        rc = stk1160_i2c_busy_wait(dev, 0x01);
+        if (rc < 0)
+                return -ENODEV;
+
+        return 0;
+}
+
+/*
+ * stk1160_i2c_xfer()
+ * the main i2c transfer function
+ */
+static int stk1160_i2c_xfer(struct i2c_adapter *i2c_adap,
+                           struct i2c_msg msgs[], int num)
+{
+        struct stk1160 *dev = i2c_adap->algo_data;
+        int addr, rc, i;
+
+        for (i = 0; i < num; i++) {
+                addr = msgs[i].addr << 1;
+                dprintk_i2c("%s: addr=%x", __func__, addr);
+
+                if (!msgs[i].len) {
+                        /* no len: check only for device presence */
+                        rc = stk1160_i2c_check_for_device(dev, addr);
+                        if (rc < 0) {
+                                dprintk_i2c(" no device\n");
+                                return rc;
+                        }
+
+                } else if (msgs[i].flags & I2C_M_RD) {
+                        /* read request without preceding register selection */
+                        dprintk_i2c(" subaddr not selected");
+                        rc = -EOPNOTSUPP;
+                        goto err;
+
+                } else if (i + 1 < num && msgs[i].len <= 2 &&
+                           (msgs[i + 1].flags & I2C_M_RD) &&
+                           msgs[i].addr == msgs[i + 1].addr) {
+
+                        if (msgs[i].len != 1 || msgs[i + 1].len != 1) {
+                                dprintk_i2c(" len not supported");
+                                rc = -EOPNOTSUPP;
+                                goto err;
+                        }
+
+                        dprintk_i2c(" subaddr=%x", msgs[i].buf[0]);
+
+                        rc = stk1160_i2c_read_reg(dev, addr, msgs[i].buf[0],
+                                msgs[i + 1].buf);
+
+                        dprintk_i2c(" read=%x", *msgs[i + 1].buf);
+
+                        /* consumed two msgs, so we skip one of them */
+                        i++;
+
+                } else {
+                        if (msgs[i].len != 2) {
+                                dprintk_i2c(" len not supported");
+                                rc = -EOPNOTSUPP;
+                                goto err;
+                        }
+
+                        dprintk_i2c(" subaddr=%x write=%x",
+                                msgs[i].buf[0],  msgs[i].buf[1]);
+
+                        rc = stk1160_i2c_write_reg(dev, addr, msgs[i].buf[0],
+                                msgs[i].buf[1]);
+                }
+
+                if (rc < 0)
+                        goto err;
+                dprintk_i2c(" OK\n");
+        }
+
+        return num;
+err:
+        dprintk_i2c(" ERROR: %d\n", rc);
+        return num;
+}
+
+/*
+ * functionality(), what da heck is this?
+ */
+static u32 functionality(struct i2c_adapter *adap)
+{
+        return I2C_FUNC_SMBUS_EMUL;
+}
+
+static struct i2c_algorithm algo = {
+        .master_xfer   = stk1160_i2c_xfer,
+        .functionality = functionality,
+};
+
+static struct i2c_adapter adap_template = {
+        .owner = THIS_MODULE,
+        .name = "stk1160",
+        .algo = &algo,
+};
+
+static struct i2c_client client_template = {
+        .name = "stk1160 internal",
+};
+
+/*
+ * stk1160_i2c_register()
+ * register i2c bus
+ */
+int stk1160_i2c_register(struct stk1160 *dev)
+{
+        int rc;
+
+        dev->i2c_adap = adap_template;
+        dev->i2c_adap.dev.parent = dev->dev;
+        strcpy(dev->i2c_adap.name, "stk1160");
+        dev->i2c_adap.algo_data = dev;
+
+        i2c_set_adapdata(&dev->i2c_adap, &dev->v4l2_dev);
+
+        rc = i2c_add_adapter(&dev->i2c_adap);
+        if (rc < 0) {
+                stk1160_err("cannot add i2c adapter (%d)\n", rc);
+                return rc;
+        }
+
+        dev->i2c_client = client_template;
+        dev->i2c_client.adapter = &dev->i2c_adap;
+
+        /* Set i2c clock divider device address */
+        stk1160_write_reg(dev, STK1160_SICTL_CD,  0x0f);
+
+        /* ??? */
+        stk1160_write_reg(dev, STK1160_ASIC + 3,  0x00);
+
+        return 0;
+}
+
+/*
+ * stk1160_i2c_unregister()
+ * unregister i2c_bus
+ */
+int stk1160_i2c_unregister(struct stk1160 *dev)
+{
+        i2c_del_adapter(&dev->i2c_adap);
+        return 0;
+}