diff options
Diffstat (limited to 'drivers/media/usb/au0828/au0828-i2c.c')
| -rw-r--r-- | drivers/media/usb/au0828/au0828-i2c.c | 401 |
1 files changed, 401 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 000000000000..4ded17fe1957 --- /dev/null +++ b/drivers/media/usb/au0828/au0828-i2c.c @@ -0,0 +1,401 @@ +/* + * Driver for the Auvitek AU0828 USB bridge + * + * Copyright (c) 2008 Steven Toth <stoth@linuxtv.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. + * + * 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. + */ + +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/io.h> + +#include "au0828.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_write_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_WRITE_ACK ? 0 : 1; +} + +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; + + dprintk(4, "%s()\n", __func__); + + au0828_write(dev, AU0828_I2C_MULTIBYTE_MODE_2FF, 0x01); + + /* Set the I2C clock */ + if (((dev->board.tuner_type == TUNER_XC5000) || + (dev->board.tuner_type == TUNER_XC5000C)) && + (dev->board.tuner_addr == msg->addr) && + (msg->len == 64)) { + /* Hack to speed up firmware load. The xc5000 lets us do up + to 400 KHz when in firmware download mode */ + au0828_write(dev, AU0828_I2C_CLK_DIVIDER_202, + AU0828_I2C_CLK_250KHZ); + } else { + /* Use the i2c clock speed in the board configuration */ + au0828_write(dev, AU0828_I2C_CLK_DIVIDER_202, + dev->board.i2c_clk_divider); + } + + /* 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; + int i; + + dprintk(4, "%s()\n", __func__); + + au0828_write(dev, AU0828_I2C_MULTIBYTE_MODE_2FF, 0x01); + + /* Set the I2C clock */ + au0828_write(dev, AU0828_I2C_CLK_DIVIDER_202, + dev->board.i2c_clk_divider); + + /* 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 struct i2c_algorithm au0828_i2c_algo_template = { + .master_xfer = i2c_xfer, + .functionality = au0828_functionality, +}; + +/* ----------------------------------------------------------------------- */ + +static struct i2c_adapter au0828_i2c_adap_template = { + .name = DRIVER_NAME, + .owner = THIS_MODULE, + .algo = &au0828_i2c_algo_template, +}; + +static 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; + printk(KERN_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__); + + memcpy(&dev->i2c_adap, &au0828_i2c_adap_template, + sizeof(dev->i2c_adap)); + memcpy(&dev->i2c_algo, &au0828_i2c_algo_template, + sizeof(dev->i2c_algo)); + memcpy(&dev->i2c_client, &au0828_i2c_client_template, + sizeof(dev->i2c_client)); + + dev->i2c_adap.dev.parent = &dev->usbdev->dev; + + strlcpy(dev->i2c_adap.name, DRIVER_NAME, + sizeof(dev->i2c_adap.name)); + + dev->i2c_adap.algo = &dev->i2c_algo; + dev->i2c_adap.algo_data = dev; + i2c_set_adapdata(&dev->i2c_adap, &dev->v4l2_dev); + i2c_add_adapter(&dev->i2c_adap); + + dev->i2c_client.adapter = &dev->i2c_adap; + + if (0 == dev->i2c_rc) { + printk(KERN_INFO "%s: i2c bus registered\n", DRIVER_NAME); + if (i2c_scan) + do_i2c_scan(DRIVER_NAME, &dev->i2c_client); + } else + printk(KERN_INFO "%s: i2c bus register FAILED\n", DRIVER_NAME); + + return dev->i2c_rc; +} + +int au0828_i2c_unregister(struct au0828_dev *dev) +{ + i2c_del_adapter(&dev->i2c_adap); + return 0; +} + |
