diff options
Diffstat (limited to 'drivers/staging/media/deprecated/saa7146/common/saa7146_i2c.c')
| -rw-r--r-- | drivers/staging/media/deprecated/saa7146/common/saa7146_i2c.c | 421 |
1 files changed, 0 insertions, 421 deletions
diff --git a/drivers/staging/media/deprecated/saa7146/common/saa7146_i2c.c b/drivers/staging/media/deprecated/saa7146/common/saa7146_i2c.c deleted file mode 100644 index 7a33fe51775a..000000000000 --- a/drivers/staging/media/deprecated/saa7146/common/saa7146_i2c.c +++ /dev/null @@ -1,421 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt - -#include "saa7146_vv.h" - -static u32 saa7146_i2c_func(struct i2c_adapter *adapter) -{ - /* DEB_I2C("'%s'\n", adapter->name); */ - - return I2C_FUNC_I2C - | I2C_FUNC_SMBUS_QUICK - | I2C_FUNC_SMBUS_READ_BYTE | I2C_FUNC_SMBUS_WRITE_BYTE - | I2C_FUNC_SMBUS_READ_BYTE_DATA | I2C_FUNC_SMBUS_WRITE_BYTE_DATA; -} - -/* this function returns the status-register of our i2c-device */ -static inline u32 saa7146_i2c_status(struct saa7146_dev *dev) -{ - u32 iicsta = saa7146_read(dev, I2C_STATUS); - /* DEB_I2C("status: 0x%08x\n", iicsta); */ - return iicsta; -} - -/* this function runs through the i2c-messages and prepares the data to be - sent through the saa7146. have a look at the specifications p. 122 ff - to understand this. it returns the number of u32s to send, or -1 - in case of an error. */ -static int saa7146_i2c_msg_prepare(const struct i2c_msg *m, int num, __le32 *op) -{ - int h1, h2; - int i, j, addr; - int mem = 0, op_count = 0; - - /* first determine size of needed memory */ - for(i = 0; i < num; i++) { - mem += m[i].len + 1; - } - - /* worst case: we need one u32 for three bytes to be send - plus one extra byte to address the device */ - mem = 1 + ((mem-1) / 3); - - /* we assume that op points to a memory of at least - * SAA7146_I2C_MEM bytes size. if we exceed this limit... - */ - if ((4 * mem) > SAA7146_I2C_MEM) { - /* DEB_I2C("cannot prepare i2c-message\n"); */ - return -ENOMEM; - } - - /* be careful: clear out the i2c-mem first */ - memset(op,0,sizeof(__le32)*mem); - - /* loop through all messages */ - for(i = 0; i < num; i++) { - - addr = i2c_8bit_addr_from_msg(&m[i]); - h1 = op_count/3; h2 = op_count%3; - op[h1] |= cpu_to_le32( (u8)addr << ((3-h2)*8)); - op[h1] |= cpu_to_le32(SAA7146_I2C_START << ((3-h2)*2)); - op_count++; - - /* loop through all bytes of message i */ - for(j = 0; j < m[i].len; j++) { - /* insert the data bytes */ - h1 = op_count/3; h2 = op_count%3; - op[h1] |= cpu_to_le32( (u32)((u8)m[i].buf[j]) << ((3-h2)*8)); - op[h1] |= cpu_to_le32( SAA7146_I2C_CONT << ((3-h2)*2)); - op_count++; - } - - } - - /* have a look at the last byte inserted: - if it was: ...CONT change it to ...STOP */ - h1 = (op_count-1)/3; h2 = (op_count-1)%3; - if ( SAA7146_I2C_CONT == (0x3 & (le32_to_cpu(op[h1]) >> ((3-h2)*2))) ) { - op[h1] &= ~cpu_to_le32(0x2 << ((3-h2)*2)); - op[h1] |= cpu_to_le32(SAA7146_I2C_STOP << ((3-h2)*2)); - } - - /* return the number of u32s to send */ - return mem; -} - -/* this functions loops through all i2c-messages. normally, it should determine - which bytes were read through the adapter and write them back to the corresponding - i2c-message. but instead, we simply write back all bytes. - fixme: this could be improved. */ -static int saa7146_i2c_msg_cleanup(const struct i2c_msg *m, int num, __le32 *op) -{ - int i, j; - int op_count = 0; - - /* loop through all messages */ - for(i = 0; i < num; i++) { - - op_count++; - - /* loop through all bytes of message i */ - for(j = 0; j < m[i].len; j++) { - /* write back all bytes that could have been read */ - m[i].buf[j] = (le32_to_cpu(op[op_count/3]) >> ((3-(op_count%3))*8)); - op_count++; - } - } - - return 0; -} - -/* this functions resets the i2c-device and returns 0 if everything was fine, otherwise -1 */ -static int saa7146_i2c_reset(struct saa7146_dev *dev) -{ - /* get current status */ - u32 status = saa7146_i2c_status(dev); - - /* clear registers for sure */ - saa7146_write(dev, I2C_STATUS, dev->i2c_bitrate); - saa7146_write(dev, I2C_TRANSFER, 0); - - /* check if any operation is still in progress */ - if ( 0 != ( status & SAA7146_I2C_BUSY) ) { - - /* yes, kill ongoing operation */ - DEB_I2C("busy_state detected\n"); - - /* set "ABORT-OPERATION"-bit (bit 7)*/ - saa7146_write(dev, I2C_STATUS, (dev->i2c_bitrate | MASK_07)); - saa7146_write(dev, MC2, (MASK_00 | MASK_16)); - msleep(SAA7146_I2C_DELAY); - - /* clear all error-bits pending; this is needed because p.123, note 1 */ - saa7146_write(dev, I2C_STATUS, dev->i2c_bitrate); - saa7146_write(dev, MC2, (MASK_00 | MASK_16)); - msleep(SAA7146_I2C_DELAY); - } - - /* check if any error is (still) present. (this can be necessary because p.123, note 1) */ - status = saa7146_i2c_status(dev); - - if ( dev->i2c_bitrate != status ) { - - DEB_I2C("error_state detected. status:0x%08x\n", status); - - /* Repeat the abort operation. This seems to be necessary - after serious protocol errors caused by e.g. the SAA7740 */ - saa7146_write(dev, I2C_STATUS, (dev->i2c_bitrate | MASK_07)); - saa7146_write(dev, MC2, (MASK_00 | MASK_16)); - msleep(SAA7146_I2C_DELAY); - - /* clear all error-bits pending */ - saa7146_write(dev, I2C_STATUS, dev->i2c_bitrate); - saa7146_write(dev, MC2, (MASK_00 | MASK_16)); - msleep(SAA7146_I2C_DELAY); - - /* the data sheet says it might be necessary to clear the status - twice after an abort */ - saa7146_write(dev, I2C_STATUS, dev->i2c_bitrate); - saa7146_write(dev, MC2, (MASK_00 | MASK_16)); - msleep(SAA7146_I2C_DELAY); - } - - /* if any error is still present, a fatal error has occurred ... */ - status = saa7146_i2c_status(dev); - if ( dev->i2c_bitrate != status ) { - DEB_I2C("fatal error. status:0x%08x\n", status); - return -1; - } - - return 0; -} - -/* this functions writes out the data-byte 'dword' to the i2c-device. - it returns 0 if ok, -1 if the transfer failed, -2 if the transfer - failed badly (e.g. address error) */ -static int saa7146_i2c_writeout(struct saa7146_dev *dev, __le32 *dword, int short_delay) -{ - u32 status = 0, mc2 = 0; - int trial = 0; - unsigned long timeout; - - /* write out i2c-command */ - DEB_I2C("before: 0x%08x (status: 0x%08x), %d\n", - *dword, saa7146_read(dev, I2C_STATUS), dev->i2c_op); - - if( 0 != (SAA7146_USE_I2C_IRQ & dev->ext->flags)) { - - saa7146_write(dev, I2C_STATUS, dev->i2c_bitrate); - saa7146_write(dev, I2C_TRANSFER, le32_to_cpu(*dword)); - - dev->i2c_op = 1; - SAA7146_ISR_CLEAR(dev, MASK_16|MASK_17); - SAA7146_IER_ENABLE(dev, MASK_16|MASK_17); - saa7146_write(dev, MC2, (MASK_00 | MASK_16)); - - timeout = HZ/100 + 1; /* 10ms */ - timeout = wait_event_interruptible_timeout(dev->i2c_wq, dev->i2c_op == 0, timeout); - if (timeout == -ERESTARTSYS || dev->i2c_op) { - SAA7146_IER_DISABLE(dev, MASK_16|MASK_17); - SAA7146_ISR_CLEAR(dev, MASK_16|MASK_17); - if (timeout == -ERESTARTSYS) - /* a signal arrived */ - return -ERESTARTSYS; - - pr_warn("%s %s [irq]: timed out waiting for end of xfer\n", - dev->name, __func__); - return -EIO; - } - status = saa7146_read(dev, I2C_STATUS); - } else { - saa7146_write(dev, I2C_STATUS, dev->i2c_bitrate); - saa7146_write(dev, I2C_TRANSFER, le32_to_cpu(*dword)); - saa7146_write(dev, MC2, (MASK_00 | MASK_16)); - - /* do not poll for i2c-status before upload is complete */ - timeout = jiffies + HZ/100 + 1; /* 10ms */ - while(1) { - mc2 = (saa7146_read(dev, MC2) & 0x1); - if( 0 != mc2 ) { - break; - } - if (time_after(jiffies,timeout)) { - pr_warn("%s %s: timed out waiting for MC2\n", - dev->name, __func__); - return -EIO; - } - } - /* wait until we get a transfer done or error */ - timeout = jiffies + HZ/100 + 1; /* 10ms */ - /* first read usually delivers bogus results... */ - saa7146_i2c_status(dev); - while(1) { - status = saa7146_i2c_status(dev); - if ((status & 0x3) != 1) - break; - if (time_after(jiffies,timeout)) { - /* this is normal when probing the bus - * (no answer from nonexisistant device...) - */ - pr_warn("%s %s [poll]: timed out waiting for end of xfer\n", - dev->name, __func__); - return -EIO; - } - if (++trial < 50 && short_delay) - udelay(10); - else - msleep(1); - } - } - - /* give a detailed status report */ - if ( 0 != (status & (SAA7146_I2C_SPERR | SAA7146_I2C_APERR | - SAA7146_I2C_DTERR | SAA7146_I2C_DRERR | - SAA7146_I2C_AL | SAA7146_I2C_ERR | - SAA7146_I2C_BUSY)) ) { - - if ( 0 == (status & SAA7146_I2C_ERR) || - 0 == (status & SAA7146_I2C_BUSY) ) { - /* it may take some time until ERR goes high - ignore */ - DEB_I2C("unexpected i2c status %04x\n", status); - } - if( 0 != (status & SAA7146_I2C_SPERR) ) { - DEB_I2C("error due to invalid start/stop condition\n"); - } - if( 0 != (status & SAA7146_I2C_DTERR) ) { - DEB_I2C("error in data transmission\n"); - } - if( 0 != (status & SAA7146_I2C_DRERR) ) { - DEB_I2C("error when receiving data\n"); - } - if( 0 != (status & SAA7146_I2C_AL) ) { - DEB_I2C("error because arbitration lost\n"); - } - - /* we handle address-errors here */ - if( 0 != (status & SAA7146_I2C_APERR) ) { - DEB_I2C("error in address phase\n"); - return -EREMOTEIO; - } - - return -EIO; - } - - /* read back data, just in case we were reading ... */ - *dword = cpu_to_le32(saa7146_read(dev, I2C_TRANSFER)); - - DEB_I2C("after: 0x%08x\n", *dword); - return 0; -} - -static int saa7146_i2c_transfer(struct saa7146_dev *dev, const struct i2c_msg *msgs, int num, int retries) -{ - int i = 0, count = 0; - __le32 *buffer = dev->d_i2c.cpu_addr; - int err = 0; - int short_delay = 0; - - if (mutex_lock_interruptible(&dev->i2c_lock)) - return -ERESTARTSYS; - - for(i=0;i<num;i++) { - DEB_I2C("msg:%d/%d\n", i+1, num); - } - - /* prepare the message(s), get number of u32s to transfer */ - count = saa7146_i2c_msg_prepare(msgs, num, buffer); - if ( 0 > count ) { - err = -EIO; - goto out; - } - - if ( count > 3 || 0 != (SAA7146_I2C_SHORT_DELAY & dev->ext->flags) ) - short_delay = 1; - - do { - /* reset the i2c-device if necessary */ - err = saa7146_i2c_reset(dev); - if ( 0 > err ) { - DEB_I2C("could not reset i2c-device\n"); - goto out; - } - - /* write out the u32s one after another */ - for(i = 0; i < count; i++) { - err = saa7146_i2c_writeout(dev, &buffer[i], short_delay); - if ( 0 != err) { - /* this one is unsatisfying: some i2c slaves on some - dvb cards don't acknowledge correctly, so the saa7146 - thinks that an address error occurred. in that case, the - transaction should be retrying, even if an address error - occurred. analog saa7146 based cards extensively rely on - i2c address probing, however, and address errors indicate that a - device is really *not* there. retrying in that case - increases the time the device needs to probe greatly, so - it should be avoided. So we bail out in irq mode after an - address error and trust the saa7146 address error detection. */ - if (-EREMOTEIO == err && 0 != (SAA7146_USE_I2C_IRQ & dev->ext->flags)) - goto out; - DEB_I2C("error while sending message(s). starting again\n"); - break; - } - } - if( 0 == err ) { - err = num; - break; - } - - /* delay a bit before retrying */ - msleep(10); - - } while (err != num && retries--); - - /* quit if any error occurred */ - if (err != num) - goto out; - - /* if any things had to be read, get the results */ - if ( 0 != saa7146_i2c_msg_cleanup(msgs, num, buffer)) { - DEB_I2C("could not cleanup i2c-message\n"); - err = -EIO; - goto out; - } - - /* return the number of delivered messages */ - DEB_I2C("transmission successful. (msg:%d)\n", err); -out: - /* another bug in revision 0: the i2c-registers get uploaded randomly by other - uploads, so we better clear them out before continuing */ - if( 0 == dev->revision ) { - __le32 zero = 0; - saa7146_i2c_reset(dev); - if( 0 != saa7146_i2c_writeout(dev, &zero, short_delay)) { - pr_info("revision 0 error. this should never happen\n"); - } - } - - mutex_unlock(&dev->i2c_lock); - return err; -} - -/* utility functions */ -static int saa7146_i2c_xfer(struct i2c_adapter* adapter, struct i2c_msg *msg, int num) -{ - struct v4l2_device *v4l2_dev = i2c_get_adapdata(adapter); - struct saa7146_dev *dev = to_saa7146_dev(v4l2_dev); - - /* use helper function to transfer data */ - return saa7146_i2c_transfer(dev, msg, num, adapter->retries); -} - - -/*****************************************************************************/ -/* i2c-adapter helper functions */ - -/* exported algorithm data */ -static const struct i2c_algorithm saa7146_algo = { - .master_xfer = saa7146_i2c_xfer, - .functionality = saa7146_i2c_func, -}; - -int saa7146_i2c_adapter_prepare(struct saa7146_dev *dev, struct i2c_adapter *i2c_adapter, u32 bitrate) -{ - DEB_EE("bitrate: 0x%08x\n", bitrate); - - /* enable i2c-port pins */ - saa7146_write(dev, MC1, (MASK_08 | MASK_24)); - - dev->i2c_bitrate = bitrate; - saa7146_i2c_reset(dev); - - if (i2c_adapter) { - i2c_set_adapdata(i2c_adapter, &dev->v4l2_dev); - i2c_adapter->dev.parent = &dev->pci->dev; - i2c_adapter->algo = &saa7146_algo; - i2c_adapter->algo_data = NULL; - i2c_adapter->timeout = SAA7146_I2C_TIMEOUT; - i2c_adapter->retries = SAA7146_I2C_RETRIES; - } - - return 0; -} |