diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-10-07 12:49:05 +0400 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-10-07 12:49:05 +0400 |
commit | 0b8e74c6f44094189dbe78baf4101acc7570c6af (patch) | |
tree | 6440561d09fb71ba5928664604ec92f29940be6b /drivers/media/common/saa7146/saa7146_i2c.c | |
parent | 7f60ba388f5b9dd8b0da463b394412dace3ab814 (diff) | |
parent | bd0d10498826ed150da5e4c45baf8b9c7088fb71 (diff) | |
download | linux-0b8e74c6f44094189dbe78baf4101acc7570c6af.tar.xz |
Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media updates from Mauro Carvalho Chehab:
"The first part of the media updates for Kernel 3.7.
This series contain:
- A major tree renaming patch series: now, drivers are organized
internally by their used bus, instead of by V4L2 and/or DVB API,
providing a cleaner driver location for hybrid drivers that
implement both APIs, and allowing to cleanup the Kconfig items and
make them more intuitive for the end user;
- Media Kernel developers are typically very lazy with their duties
of keeping the MAINTAINERS entries for their drivers updated. As
now the tree is more organized, we're doing an effort to add/update
those entries for the drivers that aren't currently orphan;
- Several DVB USB drivers got moved to a new DVB USB v2 core; the new
core fixes several bugs (as the existing one that got bitroted).
Now, suspend/resume finally started to work fine (at least with
some devices - we should expect more work with regards to it);
- added multistream support for DVB-T2, and unified the API for
DVB-S2 and ISDB-S. Backward binary support is preserved;
- as usual, a few new drivers, some V4L2 core improvements and lots
of drivers improvements and fixes.
There are some points to notice on this series:
1) you should expect a trivial merge conflict on your tree, with the
removal of Documentation/feature-removal-schedule.txt: this series
would be adding two additional entries there. I opted to not
rebase it due to this recent change;
2) With regards to the PCTV 520e udev-related breakage, I opted to
fix it in a way that the patches can be backported to 3.5 even
without your firmware fix patch. This way, Greg doesn't need to
rush backporting your patch (as there are still the firmware cache
and firmware path customization issues to be addressed there).
I'll send later a patch (likely after the end of the merge window)
reverting the rest of the DRX-K async firmware request, fully
restoring its original behaviour to allow media drivers to
initialize everything serialized as before for 3.7 and upper.
3) I'm planning to work on this weekend to test the DMABUF patches
for V4L2. The patches are on my queue for several Kernel cycles,
but, up to now, there is/was no way to test the series locally.
I have some concerns about this particular changeset with regards
to security issues, and with regards to the replacement of the old
VIDIOC_OVERLAY ioctl's that is broken on modern systems, due to
GPU drivers change. The Overlay API allows direct PCI2PCI
transfers from a media capture card into the GPU framebuffer, but
its API is crappy. Also, the only existing X11 driver that
implements it requires a XV extension that is not available
anymore on modern drivers. The DMABUF can do the same thing, but
with it is promising to be a properly-designed API. If I can
successfully test this series and be happy with it, I should be
asking you to pull them next week."
* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (717 commits)
em28xx: regression fix: use DRX-K sync firmware requests on em28xx
drxk: allow loading firmware synchrousnously
em28xx: Make all em28xx extensions to be initialized asynchronously
[media] tda18271: properly report read errors in tda18271_get_id
[media] tda18271: delay IR & RF calibration until init() if delay_cal is set
[media] MAINTAINERS: add Michael Krufky as tda827x maintainer
[media] MAINTAINERS: add Michael Krufky as tda8290 maintainer
[media] MAINTAINERS: add Michael Krufky as cxusb maintainer
[media] MAINTAINERS: add Michael Krufky as lg2160 maintainer
[media] MAINTAINERS: add Michael Krufky as lgdt3305 maintainer
[media] MAINTAINERS: add Michael Krufky as mxl111sf maintainer
[media] MAINTAINERS: add Michael Krufky as mxl5007t maintainer
[media] MAINTAINERS: add Michael Krufky as tda18271 maintainer
[media] s5p-tv: Report only multi-plane capabilities in vidioc_querycap
[media] s5p-mfc: Fix misplaced return statement in s5p_mfc_suspend()
[media] exynos-gsc: Add missing static storage class specifiers
[media] exynos-gsc: Remove <linux/version.h> header file inclusion
[media] s5p-fimc: Fix incorrect condition in fimc_lite_reqbufs()
[media] s5p-tv: Fix potential NULL pointer dereference error
[media] s5k6aa: Fix possible NULL pointer dereference
...
Diffstat (limited to 'drivers/media/common/saa7146/saa7146_i2c.c')
-rw-r--r-- | drivers/media/common/saa7146/saa7146_i2c.c | 423 |
1 files changed, 423 insertions, 0 deletions
diff --git a/drivers/media/common/saa7146/saa7146_i2c.c b/drivers/media/common/saa7146/saa7146_i2c.c new file mode 100644 index 000000000000..22027198129d --- /dev/null +++ b/drivers/media/common/saa7146/saa7146_i2c.c @@ -0,0 +1,423 @@ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <media/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++) { + + /* insert the address of the i2c-slave. + note: we get 7 bit i2c-addresses, + so we have to perform a translation */ + addr = (m[i].addr*2) + ( (0 != (m[i].flags & I2C_M_RD)) ? 1 : 0); + 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 = -1; + 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 = -1; + 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 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; +} |