diff options
Diffstat (limited to 'drivers/media/pci/saa7134/saa7134-i2c.c')
| -rw-r--r-- | drivers/media/pci/saa7134/saa7134-i2c.c | 435 |
1 files changed, 435 insertions, 0 deletions
diff --git a/drivers/media/pci/saa7134/saa7134-i2c.c b/drivers/media/pci/saa7134/saa7134-i2c.c new file mode 100644 index 000000000000..a176ec3285e0 --- /dev/null +++ b/drivers/media/pci/saa7134/saa7134-i2c.c @@ -0,0 +1,435 @@ +/* + * + * device driver for philips saa7134 based TV cards + * i2c interface support + * + * (c) 2001,02 Gerd Knorr <kraxel@bytesex.org> [SuSE Labs] + * + * 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/init.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/delay.h> + +#include "saa7134-reg.h" +#include "saa7134.h" +#include <media/v4l2-common.h> + +/* ----------------------------------------------------------- */ + +static unsigned int i2c_debug; +module_param(i2c_debug, int, 0644); +MODULE_PARM_DESC(i2c_debug,"enable debug messages [i2c]"); + +static unsigned int i2c_scan; +module_param(i2c_scan, int, 0444); +MODULE_PARM_DESC(i2c_scan,"scan i2c bus at insmod time"); + +#define d1printk if (1 == i2c_debug) printk +#define d2printk if (2 == i2c_debug) printk + +#define I2C_WAIT_DELAY 32 +#define I2C_WAIT_RETRY 16 + +/* ----------------------------------------------------------- */ + +static char *str_i2c_status[] = { + "IDLE", "DONE_STOP", "BUSY", "TO_SCL", "TO_ARB", "DONE_WRITE", + "DONE_READ", "DONE_WRITE_TO", "DONE_READ_TO", "NO_DEVICE", + "NO_ACKN", "BUS_ERR", "ARB_LOST", "SEQ_ERR", "ST_ERR", "SW_ERR" +}; + +enum i2c_status { + IDLE = 0, // no I2C command pending + DONE_STOP = 1, // I2C command done and STOP executed + BUSY = 2, // executing I2C command + TO_SCL = 3, // executing I2C command, time out on clock stretching + TO_ARB = 4, // time out on arbitration trial, still trying + DONE_WRITE = 5, // I2C command done and awaiting next write command + DONE_READ = 6, // I2C command done and awaiting next read command + DONE_WRITE_TO = 7, // see 5, and time out on status echo + DONE_READ_TO = 8, // see 6, and time out on status echo + NO_DEVICE = 9, // no acknowledge on device slave address + NO_ACKN = 10, // no acknowledge after data byte transfer + BUS_ERR = 11, // bus error + ARB_LOST = 12, // arbitration lost during transfer + SEQ_ERR = 13, // erroneous programming sequence + ST_ERR = 14, // wrong status echoing + SW_ERR = 15 // software error +}; + +static char *str_i2c_attr[] = { + "NOP", "STOP", "CONTINUE", "START" +}; + +enum i2c_attr { + NOP = 0, // no operation on I2C bus + STOP = 1, // stop condition, no associated byte transfer + CONTINUE = 2, // continue with byte transfer + START = 3 // start condition with byte transfer +}; + +static inline enum i2c_status i2c_get_status(struct saa7134_dev *dev) +{ + enum i2c_status status; + + status = saa_readb(SAA7134_I2C_ATTR_STATUS) & 0x0f; + d2printk(KERN_DEBUG "%s: i2c stat <= %s\n",dev->name, + str_i2c_status[status]); + return status; +} + +static inline void i2c_set_status(struct saa7134_dev *dev, + enum i2c_status status) +{ + d2printk(KERN_DEBUG "%s: i2c stat => %s\n",dev->name, + str_i2c_status[status]); + saa_andorb(SAA7134_I2C_ATTR_STATUS,0x0f,status); +} + +static inline void i2c_set_attr(struct saa7134_dev *dev, enum i2c_attr attr) +{ + d2printk(KERN_DEBUG "%s: i2c attr => %s\n",dev->name, + str_i2c_attr[attr]); + saa_andorb(SAA7134_I2C_ATTR_STATUS,0xc0,attr << 6); +} + +static inline int i2c_is_error(enum i2c_status status) +{ + switch (status) { + case NO_DEVICE: + case NO_ACKN: + case BUS_ERR: + case ARB_LOST: + case SEQ_ERR: + case ST_ERR: + return true; + default: + return false; + } +} + +static inline int i2c_is_idle(enum i2c_status status) +{ + switch (status) { + case IDLE: + case DONE_STOP: + return true; + default: + return false; + } +} + +static inline int i2c_is_busy(enum i2c_status status) +{ + switch (status) { + case BUSY: + case TO_SCL: + case TO_ARB: + return true; + default: + return false; + } +} + +static int i2c_is_busy_wait(struct saa7134_dev *dev) +{ + enum i2c_status status; + int count; + + for (count = 0; count < I2C_WAIT_RETRY; count++) { + status = i2c_get_status(dev); + if (!i2c_is_busy(status)) + break; + saa_wait(I2C_WAIT_DELAY); + } + if (I2C_WAIT_RETRY == count) + return false; + return true; +} + +static int i2c_reset(struct saa7134_dev *dev) +{ + enum i2c_status status; + int count; + + d2printk(KERN_DEBUG "%s: i2c reset\n",dev->name); + status = i2c_get_status(dev); + if (!i2c_is_error(status)) + return true; + i2c_set_status(dev,status); + + for (count = 0; count < I2C_WAIT_RETRY; count++) { + status = i2c_get_status(dev); + if (!i2c_is_error(status)) + break; + udelay(I2C_WAIT_DELAY); + } + if (I2C_WAIT_RETRY == count) + return false; + + if (!i2c_is_idle(status)) + return false; + + i2c_set_attr(dev,NOP); + return true; +} + +static inline int i2c_send_byte(struct saa7134_dev *dev, + enum i2c_attr attr, + unsigned char data) +{ + enum i2c_status status; + __u32 dword; + + /* have to write both attr + data in one 32bit word */ + dword = saa_readl(SAA7134_I2C_ATTR_STATUS >> 2); + dword &= 0x0f; + dword |= (attr << 6); + dword |= ((__u32)data << 8); + dword |= 0x00 << 16; /* 100 kHz */ +// dword |= 0x40 << 16; /* 400 kHz */ + dword |= 0xf0 << 24; + saa_writel(SAA7134_I2C_ATTR_STATUS >> 2, dword); + d2printk(KERN_DEBUG "%s: i2c data => 0x%x\n",dev->name,data); + + if (!i2c_is_busy_wait(dev)) + return -EIO; + status = i2c_get_status(dev); + if (i2c_is_error(status)) + return -EIO; + return 0; +} + +static inline int i2c_recv_byte(struct saa7134_dev *dev) +{ + enum i2c_status status; + unsigned char data; + + i2c_set_attr(dev,CONTINUE); + if (!i2c_is_busy_wait(dev)) + return -EIO; + status = i2c_get_status(dev); + if (i2c_is_error(status)) + return -EIO; + data = saa_readb(SAA7134_I2C_DATA); + d2printk(KERN_DEBUG "%s: i2c data <= 0x%x\n",dev->name,data); + return data; +} + +static int saa7134_i2c_xfer(struct i2c_adapter *i2c_adap, + struct i2c_msg *msgs, int num) +{ + struct saa7134_dev *dev = i2c_adap->algo_data; + enum i2c_status status; + unsigned char data; + int addr,rc,i,byte; + + status = i2c_get_status(dev); + if (!i2c_is_idle(status)) + if (!i2c_reset(dev)) + return -EIO; + + d2printk("start xfer\n"); + d1printk(KERN_DEBUG "%s: i2c xfer:",dev->name); + for (i = 0; i < num; i++) { + if (!(msgs[i].flags & I2C_M_NOSTART) || 0 == i) { + /* send address */ + d2printk("send address\n"); + addr = msgs[i].addr << 1; + if (msgs[i].flags & I2C_M_RD) + addr |= 1; + if (i > 0 && msgs[i].flags & + I2C_M_RD && msgs[i].addr != 0x40 && + msgs[i].addr != 0x19) { + /* workaround for a saa7134 i2c bug + * needed to talk to the mt352 demux + * thanks to pinnacle for the hint */ + int quirk = 0xfe; + d1printk(" [%02x quirk]",quirk); + i2c_send_byte(dev,START,quirk); + i2c_recv_byte(dev); + } + d1printk(" < %02x", addr); + rc = i2c_send_byte(dev,START,addr); + if (rc < 0) + goto err; + } + if (msgs[i].flags & I2C_M_RD) { + /* read bytes */ + d2printk("read bytes\n"); + for (byte = 0; byte < msgs[i].len; byte++) { + d1printk(" ="); + rc = i2c_recv_byte(dev); + if (rc < 0) + goto err; + d1printk("%02x", rc); + msgs[i].buf[byte] = rc; + } + /* discard mysterious extra byte when reading + from Samsung S5H1411. i2c bus gets error + if we do not. */ + if (0x19 == msgs[i].addr) { + d1printk(" ?"); + rc = i2c_recv_byte(dev); + if (rc < 0) + goto err; + d1printk("%02x", rc); + } + } else { + /* write bytes */ + d2printk("write bytes\n"); + for (byte = 0; byte < msgs[i].len; byte++) { + data = msgs[i].buf[byte]; + d1printk(" %02x", data); + rc = i2c_send_byte(dev,CONTINUE,data); + if (rc < 0) + goto err; + } + } + } + d2printk("xfer done\n"); + d1printk(" >"); + i2c_set_attr(dev,STOP); + rc = -EIO; + if (!i2c_is_busy_wait(dev)) + goto err; + status = i2c_get_status(dev); + if (i2c_is_error(status)) + goto err; + /* ensure that the bus is idle for at least one bit slot */ + msleep(1); + + d1printk("\n"); + return num; + err: + if (1 == i2c_debug) { + status = i2c_get_status(dev); + printk(" ERROR: %s\n",str_i2c_status[status]); + } + return rc; +} + +/* ----------------------------------------------------------- */ + +static u32 functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_SMBUS_EMUL; +} + +static struct i2c_algorithm saa7134_algo = { + .master_xfer = saa7134_i2c_xfer, + .functionality = functionality, +}; + +static struct i2c_adapter saa7134_adap_template = { + .owner = THIS_MODULE, + .name = "saa7134", + .algo = &saa7134_algo, +}; + +static struct i2c_client saa7134_client_template = { + .name = "saa7134 internal", +}; + +/* ----------------------------------------------------------- */ + +static int +saa7134_i2c_eeprom(struct saa7134_dev *dev, unsigned char *eedata, int len) +{ + unsigned char buf; + int i,err; + + dev->i2c_client.addr = 0xa0 >> 1; + buf = 0; + if (1 != (err = i2c_master_send(&dev->i2c_client,&buf,1))) { + printk(KERN_INFO "%s: Huh, no eeprom present (err=%d)?\n", + dev->name,err); + return -1; + } + if (len != (err = i2c_master_recv(&dev->i2c_client,eedata,len))) { + printk(KERN_WARNING "%s: i2c eeprom read error (err=%d)\n", + dev->name,err); + return -1; + } + 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"); + } + return 0; +} + +static char *i2c_devs[128] = { + [ 0x20 ] = "mpeg encoder (saa6752hs)", + [ 0xa0 >> 1 ] = "eeprom", + [ 0xc0 >> 1 ] = "tuner (analog)", + [ 0x86 >> 1 ] = "tda9887", + [ 0x5a >> 1 ] = "remote control", +}; + +static void do_i2c_scan(char *name, struct i2c_client *c) +{ + unsigned char buf; + int i,rc; + + for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) { + c->addr = i; + rc = i2c_master_recv(c,&buf,0); + if (rc < 0) + continue; + printk("%s: i2c scan: found device @ 0x%x [%s]\n", + name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???"); + } +} + +int saa7134_i2c_register(struct saa7134_dev *dev) +{ + dev->i2c_adap = saa7134_adap_template; + dev->i2c_adap.dev.parent = &dev->pci->dev; + strcpy(dev->i2c_adap.name,dev->name); + dev->i2c_adap.algo_data = dev; + i2c_set_adapdata(&dev->i2c_adap, &dev->v4l2_dev); + i2c_add_adapter(&dev->i2c_adap); + + dev->i2c_client = saa7134_client_template; + dev->i2c_client.adapter = &dev->i2c_adap; + + saa7134_i2c_eeprom(dev,dev->eedata,sizeof(dev->eedata)); + if (i2c_scan) + do_i2c_scan(dev->name,&dev->i2c_client); + + /* Instantiate the IR receiver device, if present */ + saa7134_probe_i2c_ir(dev); + return 0; +} + +int saa7134_i2c_unregister(struct saa7134_dev *dev) +{ + i2c_del_adapter(&dev->i2c_adap); + return 0; +} + +/* ----------------------------------------------------------- */ +/* + * Local variables: + * c-basic-offset: 8 + * End: + */ |