/* em28xx-i2c.c - driver for Empia EM2800/EM2820/2840 USB video capture devices Copyright (C) 2005 Ludovico Cavedon <cavedon@sssup.it> Markus Rechberger <mrechberger@gmail.com> Mauro Carvalho Chehab <mchehab@infradead.org> Sascha Sommer <saschasommer@freenet.de> 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/kernel.h> #include <linux/usb.h> #include <linux/i2c.h> #include "em28xx.h" #include "tuner-xc2028.h" #include <media/v4l2-common.h> #include <media/tuner.h> /* ----------------------------------------------------------- */ static unsigned int i2c_scan; module_param(i2c_scan, int, 0444); MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time"); static unsigned int i2c_debug; module_param(i2c_debug, int, 0644); MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]"); #define dprintk2(lvl, fmt, args...) \ do { \ if (i2c_debug >= lvl) { \ printk(KERN_DEBUG "%s at %s: " fmt, \ dev->name, __func__ , ##args); \ } \ } while (0) /* * em2800_i2c_send_max4() * send up to 4 bytes to the i2c device */ static int em2800_i2c_send_max4(struct em28xx *dev, unsigned char addr, char *buf, int len) { int ret; int write_timeout; unsigned char b2[6]; BUG_ON(len < 1 || len > 4); b2[5] = 0x80 + len - 1; b2[4] = addr; b2[3] = buf[0]; if (len > 1) b2[2] = buf[1]; if (len > 2) b2[1] = buf[2]; if (len > 3) b2[0] = buf[3]; ret = dev->em28xx_write_regs(dev, 4 - len, &b2[4 - len], 2 + len); if (ret != 2 + len) { em28xx_warn("writing to i2c device failed (error=%i)\n", ret); return -EIO; } for (write_timeout = EM2800_I2C_WRITE_TIMEOUT; write_timeout > 0; write_timeout -= 5) { ret = dev->em28xx_read_reg(dev, 0x05); if (ret == 0x80 + len - 1) return len; msleep(5); } em28xx_warn("i2c write timed out\n"); return -EIO; } /* * em2800_i2c_send_bytes() */ static int em2800_i2c_send_bytes(void *data, unsigned char addr, char *buf, short len) { char *bufPtr = buf; int ret; int wrcount = 0; int count; int maxLen = 4; struct em28xx *dev = (struct em28xx *)data; while (len > 0) { count = (len > maxLen) ? maxLen : len; ret = em2800_i2c_send_max4(dev, addr, bufPtr, count); if (ret > 0) { len -= count; bufPtr += count; wrcount += count; } else return (ret < 0) ? ret : -EFAULT; } return wrcount; } /* * em2800_i2c_check_for_device() * check if there is a i2c_device at the supplied address */ static int em2800_i2c_check_for_device(struct em28xx *dev, unsigned char addr) { char msg; int ret; int write_timeout; msg = addr; ret = dev->em28xx_write_regs(dev, 0x04, &msg, 1); if (ret < 0) { em28xx_warn("setting i2c device address failed (error=%i)\n", ret); return ret; } msg = 0x84; ret = dev->em28xx_write_regs(dev, 0x05, &msg, 1); if (ret < 0) { em28xx_warn("preparing i2c read failed (error=%i)\n", ret); return ret; } for (write_timeout = EM2800_I2C_WRITE_TIMEOUT; write_timeout > 0; write_timeout -= 5) { unsigned reg = dev->em28xx_read_reg(dev, 0x5); if (reg == 0x94) return -ENODEV; else if (reg == 0x84) return 0; msleep(5); } return -ENODEV; } /* * em2800_i2c_recv_bytes() * read from the i2c device */ static int em2800_i2c_recv_bytes(struct em28xx *dev, unsigned char addr, char *buf, int len) { int ret; /* check for the device and set i2c read address */ ret = em2800_i2c_check_for_device(dev, addr); if (ret) { em28xx_warn ("preparing read at i2c address 0x%x failed (error=%i)\n", addr, ret); return ret; } ret = dev->em28xx_read_reg_req_len(dev, 0x0, 0x3, buf, len); if (ret < 0) { em28xx_warn("reading from i2c device at 0x%x failed (error=%i)", addr, ret); return ret; } return ret; } /* * em28xx_i2c_send_bytes() */ static int em28xx_i2c_send_bytes(void *data, unsigned char addr, char *buf, short len, int stop) { int wrcount = 0; struct em28xx *dev = (struct em28xx *)data; int write_timeout, ret; wrcount = dev->em28xx_write_regs_req(dev, stop ? 2 : 3, addr, buf, len); /* Seems to be required after a write */ for (write_timeout = EM2800_I2C_WRITE_TIMEOUT; write_timeout > 0; write_timeout -= 5) { ret = dev->em28xx_read_reg(dev, 0x05); if (!ret) break; msleep(5); } return wrcount; } /* * em28xx_i2c_recv_bytes() * read a byte from the i2c device */ static int em28xx_i2c_recv_bytes(struct em28xx *dev, unsigned char addr, char *buf, int len) { int ret; ret = dev->em28xx_read_reg_req_len(dev, 2, addr, buf, len); if (ret < 0) { em28xx_warn("reading i2c device failed (error=%i)\n", ret); return ret; } if (dev->em28xx_read_reg(dev, 0x5) != 0) return -ENODEV; return ret; } /* * em28xx_i2c_check_for_device() * check if there is a i2c_device at the supplied address */ static int em28xx_i2c_check_for_device(struct em28xx *dev, unsigned char addr) { int ret; ret = dev->em28xx_read_reg_req(dev, 2, addr); if (ret < 0) { em28xx_warn("reading from i2c device failed (error=%i)\n", ret); return ret; } if (dev->em28xx_read_reg(dev, 0x5) != 0) return -ENODEV; return 0; } /* * em28xx_i2c_xfer() * the main i2c transfer function */ static int em28xx_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num) { struct em28xx *dev = i2c_adap->algo_data; int addr, rc, i, byte; if (num <= 0) return 0; for (i = 0; i < num; i++) { addr = msgs[i].addr << 1; dprintk2(2, "%s %s addr=%x len=%d:", (msgs[i].flags & I2C_M_RD) ? "read" : "write", i == num - 1 ? "stop" : "nonstop", addr, msgs[i].len); if (!msgs[i].len) { /* no len: check only for device presence */ if (dev->board.is_em2800) rc = em2800_i2c_check_for_device(dev, addr); else rc = em28xx_i2c_check_for_device(dev, addr); if (rc < 0) { dprintk2(2, " no device\n"); return rc; } } else if (msgs[i].flags & I2C_M_RD) { /* read bytes */ if (dev->board.is_em2800) rc = em2800_i2c_recv_bytes(dev, addr, msgs[i].buf, msgs[i].len); else rc = em28xx_i2c_recv_bytes(dev, addr, msgs[i].buf, msgs[i].len); if (i2c_debug >= 2) { for (byte = 0; byte < msgs[i].len; byte++) printk(" %02x", msgs[i].buf[byte]); } } else { /* write bytes */ if (i2c_debug >= 2) { for (byte = 0; byte < msgs[i].len; byte++) printk(" %02x", msgs[i].buf[byte]); } if (dev->board.is_em2800) rc = em2800_i2c_send_bytes(dev, addr, msgs[i].buf, msgs[i].len); else rc = em28xx_i2c_send_bytes(dev, addr, msgs[i].buf, msgs[i].len, i == num - 1); } if (rc < 0) goto err; if (i2c_debug >= 2) printk("\n"); } return num; err: dprintk2(2, " ERROR: %i\n", rc); return rc; } /* based on linux/sunrpc/svcauth.h and linux/hash.h * The original hash function returns a different value, if arch is x86_64 * or i386. */ static inline unsigned long em28xx_hash_mem(char *buf, int length, int bits) { unsigned long hash = 0; unsigned long l = 0; int len = 0; unsigned char c; do { if (len == length) { c = (char)len; len = -1; } else c = *buf++; l = (l << 8) | c; len++; if ((len & (32 / 8 - 1)) == 0) hash = ((hash^l) * 0x9e370001UL); } while (len); return (hash >> (32 - bits)) & 0xffffffffUL; } static int em28xx_i2c_eeprom(struct em28xx *dev, unsigned char *eedata, int len) { unsigned char buf, *p = eedata; struct em28xx_eeprom *em_eeprom = (void *)eedata; int i, err, size = len, block; if (dev->chip_id == CHIP_ID_EM2874 || dev->chip_id == CHIP_ID_EM28174 || dev->chip_id == CHIP_ID_EM2884) { /* Empia switched to a 16-bit addressable eeprom in newer devices. While we could certainly write a routine to read the eeprom, there is nothing of use in there that cannot be accessed through registers, and there is the risk that we could corrupt the eeprom (since a 16-bit read call is interpreted as a write call by 8-bit eeproms). */ return 0; } dev->i2c_client.addr = 0xa0 >> 1; /* Check if board has eeprom */ err = i2c_master_recv(&dev->i2c_client, &buf, 0); if (err < 0) { em28xx_errdev("board has no eeprom\n"); memset(eedata, 0, len); return -ENODEV; } buf = 0; err = i2c_master_send(&dev->i2c_client, &buf, 1); if (err != 1) { printk(KERN_INFO "%s: Huh, no eeprom present (err=%d)?\n", dev->name, err); return err; } while (size > 0) { if (size > 16) block = 16; else block = size; if (block != (err = i2c_master_recv(&dev->i2c_client, p, block))) { printk(KERN_WARNING "%s: i2c eeprom read error (err=%d)\n", dev->name, err); return err; } size -= block; p += block; } for (i = 0; i < len; i++) { if (0 == (i % 16)) printk(KERN_INFO "%s: i2c eeprom %02x:", dev->name, i); printk(" %02x", eedata[i]); if (15 == (i % 16)) printk("\n"); } if (em_eeprom->id == 0x9567eb1a) dev->hash = em28xx_hash_mem(eedata, len, 32); printk(KERN_INFO "%s: EEPROM ID= 0x%08x, EEPROM hash = 0x%08lx\n", dev->name, em_eeprom->id, dev->hash); printk(KERN_INFO "%s: EEPROM info:\n", dev->name); switch (em_eeprom->chip_conf >> 4 & 0x3) { case 0: printk(KERN_INFO "%s:\tNo audio on board.\n", dev->name); break; case 1: printk(KERN_INFO "%s:\tAC97 audio (5 sample rates)\n", dev->name); break; case 2: printk(KERN_INFO "%s:\tI2S audio, sample rate=32k\n", dev->name); break; case 3: printk(KERN_INFO "%s:\tI2S audio, 3 sample rates\n", dev->name); break; } if (em_eeprom->chip_conf & 1 << 3) printk(KERN_INFO "%s:\tUSB Remote wakeup capable\n", dev->name); if (em_eeprom->chip_conf & 1 << 2) printk(KERN_INFO "%s:\tUSB Self power capable\n", dev->name); switch (em_eeprom->chip_conf & 0x3) { case 0: printk(KERN_INFO "%s:\t500mA max power\n", dev->name); break; case 1: printk(KERN_INFO "%s:\t400mA max power\n", dev->name); break; case 2: printk(KERN_INFO "%s:\t300mA max power\n", dev->name); break; case 3: printk(KERN_INFO "%s:\t200mA max power\n", dev->name); break; } printk(KERN_INFO "%s:\tTable at 0x%02x, strings=0x%04x, 0x%04x, 0x%04x\n", dev->name, em_eeprom->string_idx_table, em_eeprom->string1, em_eeprom->string2, em_eeprom->string3); return 0; } /* ----------------------------------------------------------- */ /* * functionality() */ static u32 functionality(struct i2c_adapter *adap) { return I2C_FUNC_SMBUS_EMUL; } static struct i2c_algorithm em28xx_algo = { .master_xfer = em28xx_i2c_xfer, .functionality = functionality, }; static struct i2c_adapter em28xx_adap_template = { .owner = THIS_MODULE, .name = "em28xx", .algo = &em28xx_algo, }; static struct i2c_client em28xx_client_template = { .name = "em28xx internal", }; /* ----------------------------------------------------------- */ /* * i2c_devs * incomplete list of known devices */ static char *i2c_devs[128] = { [0x4a >> 1] = "saa7113h", [0x60 >> 1] = "remote IR sensor", [0x8e >> 1] = "remote IR sensor", [0x86 >> 1] = "tda9887", [0x80 >> 1] = "msp34xx", [0x88 >> 1] = "msp34xx", [0xa0 >> 1] = "eeprom", [0xb0 >> 1] = "tda9874", [0xb8 >> 1] = "tvp5150a", [0xba >> 1] = "webcam sensor or tvp5150a", [0xc0 >> 1] = "tuner (analog)", [0xc2 >> 1] = "tuner (analog)", [0xc4 >> 1] = "tuner (analog)", [0xc6 >> 1] = "tuner (analog)", }; /* * do_i2c_scan() * check i2c address range for devices */ void em28xx_do_i2c_scan(struct em28xx *dev) { u8 i2c_devicelist[128]; unsigned char buf; int i, rc; memset(i2c_devicelist, 0, ARRAY_SIZE(i2c_devicelist)); for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) { dev->i2c_client.addr = i; rc = i2c_master_recv(&dev->i2c_client, &buf, 0); if (rc < 0) continue; i2c_devicelist[i] = i; printk(KERN_INFO "%s: found i2c device @ 0x%x [%s]\n", dev->name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???"); } dev->i2c_hash = em28xx_hash_mem(i2c_devicelist, ARRAY_SIZE(i2c_devicelist), 32); } /* * em28xx_i2c_register() * register i2c bus */ int em28xx_i2c_register(struct em28xx *dev) { int retval; BUG_ON(!dev->em28xx_write_regs || !dev->em28xx_read_reg); BUG_ON(!dev->em28xx_write_regs_req || !dev->em28xx_read_reg_req); dev->i2c_adap = em28xx_adap_template; dev->i2c_adap.dev.parent = &dev->udev->dev; strcpy(dev->i2c_adap.name, dev->name); dev->i2c_adap.algo_data = dev; i2c_set_adapdata(&dev->i2c_adap, &dev->v4l2_dev); retval = i2c_add_adapter(&dev->i2c_adap); if (retval < 0) { em28xx_errdev("%s: i2c_add_adapter failed! retval [%d]\n", __func__, retval); return retval; } dev->i2c_client = em28xx_client_template; dev->i2c_client.adapter = &dev->i2c_adap; retval = em28xx_i2c_eeprom(dev, dev->eedata, sizeof(dev->eedata)); if ((retval < 0) && (retval != -ENODEV)) { em28xx_errdev("%s: em28xx_i2_eeprom failed! retval [%d]\n", __func__, retval); return retval; } if (i2c_scan) em28xx_do_i2c_scan(dev); /* Instantiate the IR receiver device, if present */ em28xx_register_i2c_ir(dev); return 0; } /* * em28xx_i2c_unregister() * unregister i2c_bus */ int em28xx_i2c_unregister(struct em28xx *dev) { i2c_del_adapter(&dev->i2c_adap); return 0; }