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path: root/drivers/media/usb/au0828/au0828-i2c.c
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Diffstat (limited to 'drivers/media/usb/au0828/au0828-i2c.c')
-rw-r--r--drivers/media/usb/au0828/au0828-i2c.c393
1 files changed, 393 insertions, 0 deletions
diff --git a/drivers/media/usb/au0828/au0828-i2c.c b/drivers/media/usb/au0828/au0828-i2c.c
new file mode 100644
index 000000000..749f90d73
--- /dev/null
+++ b/drivers/media/usb/au0828/au0828-i2c.c
@@ -0,0 +1,393 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Driver for the Auvitek AU0828 USB bridge
+ *
+ * Copyright (c) 2008 Steven Toth <stoth@linuxtv.org>
+ */
+
+#include "au0828.h"
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+
+#include "media/tuner.h"
+#include <media/v4l2-common.h>
+
+static int i2c_scan;
+module_param(i2c_scan, int, 0444);
+MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time");
+
+#define I2C_WAIT_DELAY 25
+#define I2C_WAIT_RETRY 1000
+
+static inline int i2c_slave_did_read_ack(struct i2c_adapter *i2c_adap)
+{
+ struct au0828_dev *dev = i2c_adap->algo_data;
+ return au0828_read(dev, AU0828_I2C_STATUS_201) &
+ AU0828_I2C_STATUS_NO_READ_ACK ? 0 : 1;
+}
+
+static int i2c_wait_read_ack(struct i2c_adapter *i2c_adap)
+{
+ int count;
+
+ for (count = 0; count < I2C_WAIT_RETRY; count++) {
+ if (!i2c_slave_did_read_ack(i2c_adap))
+ break;
+ udelay(I2C_WAIT_DELAY);
+ }
+
+ if (I2C_WAIT_RETRY == count)
+ return 0;
+
+ return 1;
+}
+
+static inline int i2c_is_read_busy(struct i2c_adapter *i2c_adap)
+{
+ struct au0828_dev *dev = i2c_adap->algo_data;
+ return au0828_read(dev, AU0828_I2C_STATUS_201) &
+ AU0828_I2C_STATUS_READ_DONE ? 0 : 1;
+}
+
+static int i2c_wait_read_done(struct i2c_adapter *i2c_adap)
+{
+ int count;
+
+ for (count = 0; count < I2C_WAIT_RETRY; count++) {
+ if (!i2c_is_read_busy(i2c_adap))
+ break;
+ udelay(I2C_WAIT_DELAY);
+ }
+
+ if (I2C_WAIT_RETRY == count)
+ return 0;
+
+ return 1;
+}
+
+static inline int i2c_is_write_done(struct i2c_adapter *i2c_adap)
+{
+ struct au0828_dev *dev = i2c_adap->algo_data;
+ return au0828_read(dev, AU0828_I2C_STATUS_201) &
+ AU0828_I2C_STATUS_WRITE_DONE ? 1 : 0;
+}
+
+static int i2c_wait_write_done(struct i2c_adapter *i2c_adap)
+{
+ int count;
+
+ for (count = 0; count < I2C_WAIT_RETRY; count++) {
+ if (i2c_is_write_done(i2c_adap))
+ break;
+ udelay(I2C_WAIT_DELAY);
+ }
+
+ if (I2C_WAIT_RETRY == count)
+ return 0;
+
+ return 1;
+}
+
+static inline int i2c_is_busy(struct i2c_adapter *i2c_adap)
+{
+ struct au0828_dev *dev = i2c_adap->algo_data;
+ return au0828_read(dev, AU0828_I2C_STATUS_201) &
+ AU0828_I2C_STATUS_BUSY ? 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;
+}
+
+/* FIXME: Implement join handling correctly */
+static int i2c_sendbytes(struct i2c_adapter *i2c_adap,
+ const struct i2c_msg *msg, int joined_rlen)
+{
+ int i, strobe = 0;
+ struct au0828_dev *dev = i2c_adap->algo_data;
+ u8 i2c_speed = dev->board.i2c_clk_divider;
+
+ dprintk(4, "%s()\n", __func__);
+
+ au0828_write(dev, AU0828_I2C_MULTIBYTE_MODE_2FF, 0x01);
+
+ if (((dev->board.tuner_type == TUNER_XC5000) ||
+ (dev->board.tuner_type == TUNER_XC5000C)) &&
+ (dev->board.tuner_addr == msg->addr)) {
+ /*
+ * Due to I2C clock stretch, we need to use a lower speed
+ * on xc5000 for commands. However, firmware transfer can
+ * speed up to 400 KHz.
+ */
+ if (msg->len == 64)
+ i2c_speed = AU0828_I2C_CLK_250KHZ;
+ else
+ i2c_speed = AU0828_I2C_CLK_20KHZ;
+ }
+ /* Set the I2C clock */
+ au0828_write(dev, AU0828_I2C_CLK_DIVIDER_202, i2c_speed);
+
+ /* Hardware needs 8 bit addresses */
+ au0828_write(dev, AU0828_I2C_DEST_ADDR_203, msg->addr << 1);
+
+ dprintk(4, "SEND: %02x\n", msg->addr);
+
+ /* Deal with i2c_scan */
+ if (msg->len == 0) {
+ /* The analog tuner detection code makes use of the SMBUS_QUICK
+ message (which involves a zero length i2c write). To avoid
+ checking the status register when we didn't strobe out any
+ actual bytes to the bus, just do a read check. This is
+ consistent with how I saw i2c device checking done in the
+ USB trace of the Windows driver */
+ au0828_write(dev, AU0828_I2C_TRIGGER_200,
+ AU0828_I2C_TRIGGER_READ);
+
+ if (!i2c_wait_done(i2c_adap))
+ return -EIO;
+
+ if (i2c_wait_read_ack(i2c_adap))
+ return -EIO;
+
+ return 0;
+ }
+
+ for (i = 0; i < msg->len;) {
+
+ dprintk(4, " %02x\n", msg->buf[i]);
+
+ au0828_write(dev, AU0828_I2C_WRITE_FIFO_205, msg->buf[i]);
+
+ strobe++;
+ i++;
+
+ if ((strobe >= 4) || (i >= msg->len)) {
+
+ /* Strobe the byte into the bus */
+ if (i < msg->len)
+ au0828_write(dev, AU0828_I2C_TRIGGER_200,
+ AU0828_I2C_TRIGGER_WRITE |
+ AU0828_I2C_TRIGGER_HOLD);
+ else
+ au0828_write(dev, AU0828_I2C_TRIGGER_200,
+ AU0828_I2C_TRIGGER_WRITE);
+
+ /* Reset strobe trigger */
+ strobe = 0;
+
+ if (!i2c_wait_write_done(i2c_adap))
+ return -EIO;
+
+ }
+
+ }
+ if (!i2c_wait_done(i2c_adap))
+ return -EIO;
+
+ dprintk(4, "\n");
+
+ return msg->len;
+}
+
+/* FIXME: Implement join handling correctly */
+static int i2c_readbytes(struct i2c_adapter *i2c_adap,
+ const struct i2c_msg *msg, int joined)
+{
+ struct au0828_dev *dev = i2c_adap->algo_data;
+ u8 i2c_speed = dev->board.i2c_clk_divider;
+ int i;
+
+ dprintk(4, "%s()\n", __func__);
+
+ au0828_write(dev, AU0828_I2C_MULTIBYTE_MODE_2FF, 0x01);
+
+ /*
+ * Due to xc5000c clock stretch, we cannot use full speed at
+ * readings from xc5000, as otherwise they'll fail.
+ */
+ if (((dev->board.tuner_type == TUNER_XC5000) ||
+ (dev->board.tuner_type == TUNER_XC5000C)) &&
+ (dev->board.tuner_addr == msg->addr))
+ i2c_speed = AU0828_I2C_CLK_20KHZ;
+
+ /* Set the I2C clock */
+ au0828_write(dev, AU0828_I2C_CLK_DIVIDER_202, i2c_speed);
+
+ /* Hardware needs 8 bit addresses */
+ au0828_write(dev, AU0828_I2C_DEST_ADDR_203, msg->addr << 1);
+
+ dprintk(4, " RECV:\n");
+
+ /* Deal with i2c_scan */
+ if (msg->len == 0) {
+ au0828_write(dev, AU0828_I2C_TRIGGER_200,
+ AU0828_I2C_TRIGGER_READ);
+
+ if (i2c_wait_read_ack(i2c_adap))
+ return -EIO;
+ return 0;
+ }
+
+ for (i = 0; i < msg->len;) {
+
+ i++;
+
+ if (i < msg->len)
+ au0828_write(dev, AU0828_I2C_TRIGGER_200,
+ AU0828_I2C_TRIGGER_READ |
+ AU0828_I2C_TRIGGER_HOLD);
+ else
+ au0828_write(dev, AU0828_I2C_TRIGGER_200,
+ AU0828_I2C_TRIGGER_READ);
+
+ if (!i2c_wait_read_done(i2c_adap))
+ return -EIO;
+
+ msg->buf[i-1] = au0828_read(dev, AU0828_I2C_READ_FIFO_209) &
+ 0xff;
+
+ dprintk(4, " %02x\n", msg->buf[i-1]);
+ }
+ if (!i2c_wait_done(i2c_adap))
+ return -EIO;
+
+ dprintk(4, "\n");
+
+ return msg->len;
+}
+
+static int i2c_xfer(struct i2c_adapter *i2c_adap,
+ struct i2c_msg *msgs, int num)
+{
+ int i, retval = 0;
+
+ dprintk(4, "%s(num = %d)\n", __func__, num);
+
+ for (i = 0; i < num; i++) {
+ dprintk(4, "%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 au0828_functionality(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
+}
+
+static const struct i2c_algorithm au0828_i2c_algo_template = {
+ .master_xfer = i2c_xfer,
+ .functionality = au0828_functionality,
+};
+
+/* ----------------------------------------------------------------------- */
+
+static const struct i2c_adapter au0828_i2c_adap_template = {
+ .name = KBUILD_MODNAME,
+ .owner = THIS_MODULE,
+ .algo = &au0828_i2c_algo_template,
+};
+
+static const struct i2c_client au0828_i2c_client_template = {
+ .name = "au0828 internal",
+};
+
+static char *i2c_devs[128] = {
+ [0x8e >> 1] = "au8522",
+ [0xa0 >> 1] = "eeprom",
+ [0xc2 >> 1] = "tuner/xc5000",
+};
+
+static void do_i2c_scan(char *name, struct i2c_client *c)
+{
+ unsigned char buf;
+ int i, rc;
+
+ for (i = 0; i < 128; i++) {
+ c->addr = i;
+ rc = i2c_master_recv(c, &buf, 0);
+ if (rc < 0)
+ continue;
+ pr_info("%s: i2c scan: found device @ 0x%x [%s]\n",
+ name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
+ }
+}
+
+/* init + register i2c adapter */
+int au0828_i2c_register(struct au0828_dev *dev)
+{
+ dprintk(1, "%s()\n", __func__);
+
+ dev->i2c_adap = au0828_i2c_adap_template;
+ dev->i2c_algo = au0828_i2c_algo_template;
+ dev->i2c_client = au0828_i2c_client_template;
+
+ dev->i2c_adap.dev.parent = &dev->usbdev->dev;
+
+ strscpy(dev->i2c_adap.name, KBUILD_MODNAME,
+ sizeof(dev->i2c_adap.name));
+
+ dev->i2c_adap.algo = &dev->i2c_algo;
+ dev->i2c_adap.algo_data = dev;
+#ifdef CONFIG_VIDEO_AU0828_V4L2
+ i2c_set_adapdata(&dev->i2c_adap, &dev->v4l2_dev);
+#else
+ i2c_set_adapdata(&dev->i2c_adap, dev);
+#endif
+ i2c_add_adapter(&dev->i2c_adap);
+
+ dev->i2c_client.adapter = &dev->i2c_adap;
+
+ if (0 == dev->i2c_rc) {
+ pr_info("i2c bus registered\n");
+ if (i2c_scan)
+ do_i2c_scan(KBUILD_MODNAME, &dev->i2c_client);
+ } else
+ pr_info("i2c bus register FAILED\n");
+
+ return dev->i2c_rc;
+}
+
+int au0828_i2c_unregister(struct au0828_dev *dev)
+{
+ i2c_del_adapter(&dev->i2c_adap);
+ return 0;
+}
+
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-06 08:36:38 +0000