diff options
Diffstat (limited to 'drivers/staging/media/usbvision/usbvision-i2c.c')
| -rw-r--r-- | drivers/staging/media/usbvision/usbvision-i2c.c | 438 |
1 files changed, 438 insertions, 0 deletions
diff --git a/drivers/staging/media/usbvision/usbvision-i2c.c b/drivers/staging/media/usbvision/usbvision-i2c.c new file mode 100644 index 000000000000..6e4df3335b1b --- /dev/null +++ b/drivers/staging/media/usbvision/usbvision-i2c.c @@ -0,0 +1,438 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * usbvision_i2c.c + * i2c algorithm for USB-I2C Bridges + * + * Copyright (c) 1999-2007 Joerg Heckenbach <joerg@heckenbach-aw.de> + * Dwaine Garden <dwainegarden@rogers.com> + * + * This module is part of usbvision driver project. + * Updates to driver completed by Dwaine P. Garden + */ + + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/uaccess.h> +#include <linux/ioport.h> +#include <linux/errno.h> +#include <linux/usb.h> +#include <linux/i2c.h> +#include "usbvision.h" + +#define DBG_I2C (1 << 0) + +static int i2c_debug; + +module_param(i2c_debug, int, 0644); /* debug_i2c_usb mode of the device driver */ +MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]"); + +#define PDEBUG(level, fmt, args...) { \ + if (i2c_debug & (level)) \ + printk(KERN_INFO KBUILD_MODNAME ":[%s:%d] " fmt, \ + __func__, __LINE__ , ## args); \ + } + +static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf, + short len); +static int usbvision_i2c_read(struct usb_usbvision *usbvision, unsigned char addr, char *buf, + short len); + +static inline int try_write_address(struct i2c_adapter *i2c_adap, + unsigned char addr, int retries) +{ + struct usb_usbvision *usbvision; + int i, ret = -1; + char buf[4]; + + usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap); + buf[0] = 0x00; + for (i = 0; i <= retries; i++) { + ret = (usbvision_i2c_write(usbvision, addr, buf, 1)); + if (ret == 1) + break; /* success! */ + udelay(5); + if (i == retries) /* no success */ + break; + udelay(10); + } + if (i) { + PDEBUG(DBG_I2C, "Needed %d retries for address %#2x", i, addr); + PDEBUG(DBG_I2C, "Maybe there's no device at this address"); + } + return ret; +} + +static inline int try_read_address(struct i2c_adapter *i2c_adap, + unsigned char addr, int retries) +{ + struct usb_usbvision *usbvision; + int i, ret = -1; + char buf[4]; + + usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap); + for (i = 0; i <= retries; i++) { + ret = (usbvision_i2c_read(usbvision, addr, buf, 1)); + if (ret == 1) + break; /* success! */ + udelay(5); + if (i == retries) /* no success */ + break; + udelay(10); + } + if (i) { + PDEBUG(DBG_I2C, "Needed %d retries for address %#2x", i, addr); + PDEBUG(DBG_I2C, "Maybe there's no device at this address"); + } + return ret; +} + +static inline int usb_find_address(struct i2c_adapter *i2c_adap, + struct i2c_msg *msg, int retries, + unsigned char *add) +{ + unsigned short flags = msg->flags; + + unsigned char addr; + int ret; + + addr = (msg->addr << 1); + if (flags & I2C_M_RD) + addr |= 1; + + add[0] = addr; + if (flags & I2C_M_RD) + ret = try_read_address(i2c_adap, addr, retries); + else + ret = try_write_address(i2c_adap, addr, retries); + + if (ret != 1) + return -EREMOTEIO; + + return 0; +} + +static int +usbvision_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num) +{ + struct i2c_msg *pmsg; + struct usb_usbvision *usbvision; + int i, ret; + unsigned char addr = 0; + + usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap); + + for (i = 0; i < num; i++) { + pmsg = &msgs[i]; + ret = usb_find_address(i2c_adap, pmsg, i2c_adap->retries, &addr); + if (ret != 0) { + PDEBUG(DBG_I2C, "got NAK from device, message #%d", i); + return (ret < 0) ? ret : -EREMOTEIO; + } + + if (pmsg->flags & I2C_M_RD) { + /* read bytes into buffer */ + ret = (usbvision_i2c_read(usbvision, addr, pmsg->buf, pmsg->len)); + if (ret < pmsg->len) + return (ret < 0) ? ret : -EREMOTEIO; + } else { + /* write bytes from buffer */ + ret = (usbvision_i2c_write(usbvision, addr, pmsg->buf, pmsg->len)); + if (ret < pmsg->len) + return (ret < 0) ? ret : -EREMOTEIO; + } + } + return num; +} + +static u32 functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +/* -----exported algorithm data: ------------------------------------- */ + +static const struct i2c_algorithm usbvision_algo = { + .master_xfer = usbvision_i2c_xfer, + .smbus_xfer = NULL, + .functionality = functionality, +}; + + +/* ----------------------------------------------------------------------- */ +/* usbvision specific I2C functions */ +/* ----------------------------------------------------------------------- */ +static const struct i2c_adapter i2c_adap_template; + +int usbvision_i2c_register(struct usb_usbvision *usbvision) +{ + static unsigned short saa711x_addrs[] = { + 0x4a >> 1, 0x48 >> 1, /* SAA7111, SAA7111A and SAA7113 */ + 0x42 >> 1, 0x40 >> 1, /* SAA7114, SAA7115 and SAA7118 */ + I2C_CLIENT_END }; + + if (usbvision->registered_i2c) + return 0; + + usbvision->i2c_adap = i2c_adap_template; + + snprintf(usbvision->i2c_adap.name, sizeof(usbvision->i2c_adap.name), + "usbvision-%d-%s", + usbvision->dev->bus->busnum, usbvision->dev->devpath); + PDEBUG(DBG_I2C, "Adaptername: %s", usbvision->i2c_adap.name); + usbvision->i2c_adap.dev.parent = &usbvision->dev->dev; + + i2c_set_adapdata(&usbvision->i2c_adap, &usbvision->v4l2_dev); + + if (usbvision_write_reg(usbvision, USBVISION_SER_MODE, USBVISION_IIC_LRNACK) < 0) { + printk(KERN_ERR "usbvision_i2c_register: can't write reg\n"); + return -EBUSY; + } + + PDEBUG(DBG_I2C, "I2C debugging is enabled [i2c]"); + PDEBUG(DBG_I2C, "ALGO debugging is enabled [i2c]"); + + /* register new adapter to i2c module... */ + + usbvision->i2c_adap.algo = &usbvision_algo; + + usbvision->i2c_adap.timeout = 100; /* default values, should */ + usbvision->i2c_adap.retries = 3; /* be replaced by defines */ + + i2c_add_adapter(&usbvision->i2c_adap); + + PDEBUG(DBG_I2C, "i2c bus for %s registered", usbvision->i2c_adap.name); + + /* Request the load of the i2c modules we need */ + switch (usbvision_device_data[usbvision->dev_model].codec) { + case CODEC_SAA7113: + case CODEC_SAA7111: + /* Without this delay the detection of the saa711x is + hit-and-miss. */ + mdelay(10); + v4l2_i2c_new_subdev(&usbvision->v4l2_dev, + &usbvision->i2c_adap, + "saa7115_auto", 0, saa711x_addrs); + break; + } + if (usbvision_device_data[usbvision->dev_model].tuner == 1) { + struct v4l2_subdev *sd; + enum v4l2_i2c_tuner_type type; + struct tuner_setup tun_setup; + + sd = v4l2_i2c_new_subdev(&usbvision->v4l2_dev, + &usbvision->i2c_adap, + "tuner", 0, v4l2_i2c_tuner_addrs(ADDRS_DEMOD)); + /* depending on whether we found a demod or not, select + the tuner type. */ + type = sd ? ADDRS_TV_WITH_DEMOD : ADDRS_TV; + + sd = v4l2_i2c_new_subdev(&usbvision->v4l2_dev, + &usbvision->i2c_adap, + "tuner", 0, v4l2_i2c_tuner_addrs(type)); + + if (sd == NULL) + return -ENODEV; + if (usbvision->tuner_type != -1) { + tun_setup.mode_mask = T_ANALOG_TV | T_RADIO; + tun_setup.type = usbvision->tuner_type; + tun_setup.addr = v4l2_i2c_subdev_addr(sd); + call_all(usbvision, tuner, s_type_addr, &tun_setup); + } + } + usbvision->registered_i2c = 1; + + return 0; +} + +int usbvision_i2c_unregister(struct usb_usbvision *usbvision) +{ + if (!usbvision->registered_i2c) + return 0; + + i2c_del_adapter(&(usbvision->i2c_adap)); + usbvision->registered_i2c = 0; + + PDEBUG(DBG_I2C, "i2c bus for %s unregistered", usbvision->i2c_adap.name); + + return 0; +} + +static int +usbvision_i2c_read_max4(struct usb_usbvision *usbvision, unsigned char addr, + char *buf, short len) +{ + int rc, retries; + + for (retries = 5;;) { + rc = usbvision_write_reg(usbvision, USBVISION_SER_ADRS, addr); + if (rc < 0) + return rc; + + /* Initiate byte read cycle */ + /* USBVISION_SER_CONT <- d0-d2 n. of bytes to r/w */ + /* d3 0=Wr 1=Rd */ + rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, + (len & 0x07) | 0x18); + if (rc < 0) + return rc; + + /* Test for Busy and ACK */ + do { + /* USBVISION_SER_CONT -> d4 == 0 busy */ + rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT); + } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */ + if (rc < 0) + return rc; + + /* USBVISION_SER_CONT -> d5 == 1 Not ack */ + if ((rc & 0x20) == 0) /* Ack? */ + break; + + /* I2C abort */ + rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00); + if (rc < 0) + return rc; + + if (--retries < 0) + return -1; + } + + switch (len) { + case 4: + buf[3] = usbvision_read_reg(usbvision, USBVISION_SER_DAT4); + /* fall through */ + case 3: + buf[2] = usbvision_read_reg(usbvision, USBVISION_SER_DAT3); + /* fall through */ + case 2: + buf[1] = usbvision_read_reg(usbvision, USBVISION_SER_DAT2); + /* fall through */ + case 1: + buf[0] = usbvision_read_reg(usbvision, USBVISION_SER_DAT1); + break; + default: + printk(KERN_ERR + "usbvision_i2c_read_max4: buffer length > 4\n"); + } + + if (i2c_debug & DBG_I2C) { + int idx; + + for (idx = 0; idx < len; idx++) + PDEBUG(DBG_I2C, "read %x from address %x", (unsigned char)buf[idx], addr); + } + return len; +} + + +static int usbvision_i2c_write_max4(struct usb_usbvision *usbvision, + unsigned char addr, const char *buf, + short len) +{ + int rc, retries; + int i; + unsigned char *value = usbvision->ctrl_urb_buffer; + unsigned char ser_cont; + + ser_cont = (len & 0x07) | 0x10; + + value[0] = addr; + value[1] = ser_cont; + for (i = 0; i < len; i++) + value[i + 2] = buf[i]; + + for (retries = 5;;) { + rc = usb_control_msg(usbvision->dev, + usb_sndctrlpipe(usbvision->dev, 1), + USBVISION_OP_CODE, + USB_DIR_OUT | USB_TYPE_VENDOR | + USB_RECIP_ENDPOINT, 0, + (__u16) USBVISION_SER_ADRS, value, + len + 2, HZ); + + if (rc < 0) + return rc; + + rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, + (len & 0x07) | 0x10); + if (rc < 0) + return rc; + + /* Test for Busy and ACK */ + do { + rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT); + } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */ + if (rc < 0) + return rc; + + if ((rc & 0x20) == 0) /* Ack? */ + break; + + /* I2C abort */ + usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00); + + if (--retries < 0) + return -1; + + } + + if (i2c_debug & DBG_I2C) { + int idx; + + for (idx = 0; idx < len; idx++) + PDEBUG(DBG_I2C, "wrote %x at address %x", (unsigned char)buf[idx], addr); + } + return len; +} + +static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf, + short len) +{ + char *buf_ptr = buf; + int retval; + int wrcount = 0; + int count; + int max_len = 4; + + while (len > 0) { + count = (len > max_len) ? max_len : len; + retval = usbvision_i2c_write_max4(usbvision, addr, buf_ptr, count); + if (retval > 0) { + len -= count; + buf_ptr += count; + wrcount += count; + } else + return (retval < 0) ? retval : -EFAULT; + } + return wrcount; +} + +static int usbvision_i2c_read(struct usb_usbvision *usbvision, unsigned char addr, char *buf, + short len) +{ + char temp[4]; + int retval, i; + int rdcount = 0; + int count; + + while (len > 0) { + count = (len > 3) ? 4 : len; + retval = usbvision_i2c_read_max4(usbvision, addr, temp, count); + if (retval > 0) { + for (i = 0; i < len; i++) + buf[rdcount + i] = temp[i]; + len -= count; + rdcount += count; + } else + return (retval < 0) ? retval : -EFAULT; + } + return rdcount; +} + +static const struct i2c_adapter i2c_adap_template = { + .owner = THIS_MODULE, + .name = "usbvision", +}; |