There may be several reasons why you may need to use a certain speed
on an I2C bus. E.g.
- When several devices are attached to the bus, the speed must be
selected according to the slowest device.
- Electrical conditions may limit the usuable speed on the bus for
different reasons.
With an I2C multiplexer, it is possible to group the attached devices
after their preferred speed by e.g. put all "slow" devices on a separate
channel on the multiplexer.
Consider the following topology:
.----------. 100kHz .--------.
.--------. 400kHz | |--------| dev D1 |
| root |--+-----| I2C MUX | '--------'
'--------' | | |--. 400kHz .--------.
| '----------' '-------| dev D2 |
| .--------. '--------'
'--| dev D3 |
'--------'
One requirement with this design is that a multiplexer may only use the
same or lower bus speed as its parent.
Otherwise, if the multiplexer would have to increase the bus frequency,
then all siblings (D3 in this case) would run into a clock speed it may
not support.
The bus frequency for each channel is set in the devicetree. As the
i2c-mux bindings import the i2c-controller schema, the clock-frequency
property is already allowed.
If no clock-frequency property is set, the channel inherit their parent
bus speed.
The following example uses dt bindings to illustrate the topology above:
i2c {
clock-frequency = <400000>;
i2c-mux {
i2c@0 {
clock-frequency = <100000>;
D1 {
...
};
};
i2c@1 {
D2 {
...
};
};
};
D3 {
...
}
};
Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com>
---
drivers/i2c/i2c-mux.c | 115 ++++++++++++++++++++++++++++++++++++++++++++------
1 file changed, 103 insertions(+), 12 deletions(-)
diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c
index 4d8690981a55dc0e1b35454971923791e6ed9f7f..5987853afa75cb58e1c6af6c7e7d52873ea53507 100644
--- a/drivers/i2c/i2c-mux.c
+++ b/drivers/i2c/i2c-mux.c
@@ -36,6 +36,72 @@ struct i2c_mux_priv {
u32 chan_id;
};
+static int i2c_mux_select_chan(struct i2c_adapter *adap, u32 chan_id)
+{
+ struct i2c_mux_priv *priv = adap->algo_data;
+ struct i2c_mux_core *muxc = priv->muxc;
+ struct i2c_adapter *parent = muxc->parent;
+ struct i2c_adapter *root;
+ int ret;
+
+ if (priv->adap.clock_hz && priv->adap.clock_hz != parent->clock_hz) {
+ root = i2c_root_adapter(&adap->dev);
+
+ /* if we are parent-locked and the root adapter is our parent,
+ * we already have the lock we need. Otherwise take the bus lock for the root
+ * adaper before changing bus clock.
+ */
+ if ((root != parent && !muxc->mux_locked) || muxc->mux_locked)
+ i2c_lock_bus(parent, I2C_LOCK_ROOT_ADAPTER);
+
+ ret = i2c_adapter_set_clk_freq(root, priv->adap.clock_hz);
+
+ if ((root != parent && !muxc->mux_locked) || muxc->mux_locked)
+ i2c_unlock_bus(parent, I2C_LOCK_ROOT_ADAPTER);
+
+ if (ret < 0) {
+ dev_err(&adap->dev,
+ "Failed to set clock frequency %dHz on root adapter %s: %d\n",
+ priv->adap.clock_hz, root->name, ret);
+
+ return ret;
+ }
+ }
+
+ return muxc->select(muxc, priv->chan_id);
+}
+
+static void i2c_mux_deselect_chan(struct i2c_adapter *adap, u32 chan_id)
+{
+ struct i2c_mux_priv *priv = adap->algo_data;
+ struct i2c_mux_core *muxc = priv->muxc;
+ struct i2c_adapter *parent = muxc->parent;
+ struct i2c_adapter *root;
+ int ret;
+
+ if (parent->clock_hz && parent->clock_hz != priv->adap.clock_hz) {
+ root = i2c_root_adapter(&parent->dev);
+
+ /* if we are parent-locked and the root adapter is our parent,
+ * we already have the lock we need. Otherwise take the bus lock for the root
+ * adaper before changing bus clock.
+ */
+ if ((root != parent && !muxc->mux_locked) || muxc->mux_locked)
+ i2c_lock_bus(parent, I2C_LOCK_ROOT_ADAPTER);
+
+ ret = i2c_adapter_set_clk_freq(root, parent->clock_hz);
+
+ if ((root != parent && !muxc->mux_locked) || muxc->mux_locked)
+ i2c_unlock_bus(parent, I2C_LOCK_ROOT_ADAPTER);
+
+ if (ret < 0)
+ return;
+ }
+
+ if (muxc->deselect)
+ muxc->deselect(muxc, priv->chan_id);
+}
+
static int __i2c_mux_master_xfer(struct i2c_adapter *adap,
struct i2c_msg msgs[], int num)
{
@@ -46,11 +112,11 @@ static int __i2c_mux_master_xfer(struct i2c_adapter *adap,
/* Switch to the right mux port and perform the transfer. */
- ret = muxc->select(muxc, priv->chan_id);
+ ret = i2c_mux_select_chan(adap, priv->chan_id);
if (ret >= 0)
ret = __i2c_transfer(parent, msgs, num);
- if (muxc->deselect)
- muxc->deselect(muxc, priv->chan_id);
+
+ i2c_mux_deselect_chan(adap, priv->chan_id);
return ret;
}
@@ -65,11 +131,11 @@ static int i2c_mux_master_xfer(struct i2c_adapter *adap,
/* Switch to the right mux port and perform the transfer. */
- ret = muxc->select(muxc, priv->chan_id);
+ ret = i2c_mux_select_chan(adap, priv->chan_id);
if (ret >= 0)
ret = i2c_transfer(parent, msgs, num);
- if (muxc->deselect)
- muxc->deselect(muxc, priv->chan_id);
+
+ i2c_mux_deselect_chan(adap, priv->chan_id);
return ret;
}
@@ -86,12 +152,12 @@ static int __i2c_mux_smbus_xfer(struct i2c_adapter *adap,
/* Select the right mux port and perform the transfer. */
- ret = muxc->select(muxc, priv->chan_id);
+ ret = i2c_mux_select_chan(adap, priv->chan_id);
if (ret >= 0)
ret = __i2c_smbus_xfer(parent, addr, flags,
read_write, command, size, data);
- if (muxc->deselect)
- muxc->deselect(muxc, priv->chan_id);
+
+ i2c_mux_deselect_chan(adap, priv->chan_id);
return ret;
}
@@ -108,12 +174,12 @@ static int i2c_mux_smbus_xfer(struct i2c_adapter *adap,
/* Select the right mux port and perform the transfer. */
- ret = muxc->select(muxc, priv->chan_id);
+ ret = i2c_mux_select_chan(adap, priv->chan_id);
if (ret >= 0)
ret = i2c_smbus_xfer(parent, addr, flags,
read_write, command, size, data);
- if (muxc->deselect)
- muxc->deselect(muxc, priv->chan_id);
+
+ i2c_mux_deselect_chan(adap, priv->chan_id);
return ret;
}
@@ -365,6 +431,31 @@ int i2c_mux_add_adapter(struct i2c_mux_core *muxc,
}
}
+ of_property_read_u32(child, "clock-frequency", &priv->adap.clock_hz);
+
+ /*
+ * Warn if the mux adapter is not parent-locked as
+ * this may cause issues for some hardware topologies.
+ */
+ if ((priv->adap.clock_hz < parent->clock_hz) && muxc->mux_locked)
+ dev_warn(muxc->dev,
+ "channel %u is slower than parent on a non parent-locked mux\n",
+ chan_id);
+
+ /* If the mux adapter has no clock-frequency property, inherit from parent */
+ if (!priv->adap.clock_hz)
+ priv->adap.clock_hz = parent->clock_hz;
+
+ /* We don't support mux adapters faster than their parent */
+ if (priv->adap.clock_hz > parent->clock_hz) {
+ dev_err(muxc->dev,
+ "channel (%u) is faster (%u) than parent (%u)\n",
+ chan_id, priv->adap.clock_hz, parent->clock_hz);
+
+ of_node_put(mux_node);
+ goto err_free_priv;
+ }
+
priv->adap.dev.of_node = child;
of_node_put(mux_node);
}
--
2.50.1Hi Marcus,
kernel test robot noticed the following build warnings:
url: https://github.com/intel-lab-lkp/linux/commits/Marcus-Folkesson/i2c-core-add-callback-to-change-bus-frequency/20251002-224414
base: 22f20375f5b71f30c0d6896583b93b6e4bba7279
patch link: https://lore.kernel.org/r/20251002-i2c-mux-v2-2-b698564cd956%40gmail.com
patch subject: [PATCH v2 2/5] i2c: mux: add support for per channel bus frequency
config: i386-randconfig-141-20251003 (https://download.01.org/0day-ci/archive/20251003/202510031735.TE7FVj0R-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
| Closes: https://lore.kernel.org/r/202510031735.TE7FVj0R-lkp@intel.com/
smatch warnings:
drivers/i2c/i2c-mux.c:506 i2c_mux_add_adapter() error: uninitialized symbol 'ret'.
vim +/ret +506 drivers/i2c/i2c-mux.c
a7ab72390b7706 Peter Rosin 2016-04-20 336 int i2c_mux_add_adapter(struct i2c_mux_core *muxc,
fec1982d70721c Heiner Kallweit 2024-04-18 337 u32 force_nr, u32 chan_id)
a7ab72390b7706 Peter Rosin 2016-04-20 338 {
a7ab72390b7706 Peter Rosin 2016-04-20 339 struct i2c_adapter *parent = muxc->parent;
0826374bff5741 Michael Lawnick 2010-08-11 340 struct i2c_mux_priv *priv;
c9449affad2ae0 Gerlando Falauto 2014-11-13 341 char symlink_name[20];
0826374bff5741 Michael Lawnick 2010-08-11 342 int ret;
0826374bff5741 Michael Lawnick 2010-08-11 343
a7ab72390b7706 Peter Rosin 2016-04-20 344 if (muxc->num_adapters >= muxc->max_adapters) {
a7ab72390b7706 Peter Rosin 2016-04-20 345 dev_err(muxc->dev, "No room for more i2c-mux adapters\n");
a7ab72390b7706 Peter Rosin 2016-04-20 346 return -EINVAL;
a7ab72390b7706 Peter Rosin 2016-04-20 347 }
a7ab72390b7706 Peter Rosin 2016-04-20 348
a7ab72390b7706 Peter Rosin 2016-04-20 349 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
0826374bff5741 Michael Lawnick 2010-08-11 350 if (!priv)
a7ab72390b7706 Peter Rosin 2016-04-20 351 return -ENOMEM;
0826374bff5741 Michael Lawnick 2010-08-11 352
0826374bff5741 Michael Lawnick 2010-08-11 353 /* Set up private adapter data */
a7ab72390b7706 Peter Rosin 2016-04-20 354 priv->muxc = muxc;
0826374bff5741 Michael Lawnick 2010-08-11 355 priv->chan_id = chan_id;
0826374bff5741 Michael Lawnick 2010-08-11 356
0826374bff5741 Michael Lawnick 2010-08-11 357 /* Need to do algo dynamically because we don't know ahead
0826374bff5741 Michael Lawnick 2010-08-11 358 * of time what sort of physical adapter we'll be dealing with.
0826374bff5741 Michael Lawnick 2010-08-11 359 */
6ef91fcca8a8ba Peter Rosin 2016-05-04 360 if (parent->algo->master_xfer) {
6ef91fcca8a8ba Peter Rosin 2016-05-04 361 if (muxc->mux_locked)
614b1c3cbfb0ec Wolfram Sang 2025-06-12 362 priv->algo.xfer = i2c_mux_master_xfer;
6ef91fcca8a8ba Peter Rosin 2016-05-04 363 else
614b1c3cbfb0ec Wolfram Sang 2025-06-12 364 priv->algo.xfer = __i2c_mux_master_xfer;
6ef91fcca8a8ba Peter Rosin 2016-05-04 365 }
7168bff2cfd710 Wolfram Sang 2019-04-03 366 if (parent->algo->master_xfer_atomic)
614b1c3cbfb0ec Wolfram Sang 2025-06-12 367 priv->algo.xfer_atomic = priv->algo.master_xfer;
7168bff2cfd710 Wolfram Sang 2019-04-03 368
6ef91fcca8a8ba Peter Rosin 2016-05-04 369 if (parent->algo->smbus_xfer) {
6ef91fcca8a8ba Peter Rosin 2016-05-04 370 if (muxc->mux_locked)
0826374bff5741 Michael Lawnick 2010-08-11 371 priv->algo.smbus_xfer = i2c_mux_smbus_xfer;
6ef91fcca8a8ba Peter Rosin 2016-05-04 372 else
6ef91fcca8a8ba Peter Rosin 2016-05-04 373 priv->algo.smbus_xfer = __i2c_mux_smbus_xfer;
6ef91fcca8a8ba Peter Rosin 2016-05-04 374 }
7168bff2cfd710 Wolfram Sang 2019-04-03 375 if (parent->algo->smbus_xfer_atomic)
7168bff2cfd710 Wolfram Sang 2019-04-03 376 priv->algo.smbus_xfer_atomic = priv->algo.smbus_xfer;
7168bff2cfd710 Wolfram Sang 2019-04-03 377
0826374bff5741 Michael Lawnick 2010-08-11 378 priv->algo.functionality = i2c_mux_functionality;
0826374bff5741 Michael Lawnick 2010-08-11 379
0826374bff5741 Michael Lawnick 2010-08-11 380 /* Now fill out new adapter structure */
0826374bff5741 Michael Lawnick 2010-08-11 381 snprintf(priv->adap.name, sizeof(priv->adap.name),
0826374bff5741 Michael Lawnick 2010-08-11 382 "i2c-%d-mux (chan_id %d)", i2c_adapter_id(parent), chan_id);
0826374bff5741 Michael Lawnick 2010-08-11 383 priv->adap.owner = THIS_MODULE;
0826374bff5741 Michael Lawnick 2010-08-11 384 priv->adap.algo = &priv->algo;
0826374bff5741 Michael Lawnick 2010-08-11 385 priv->adap.algo_data = priv;
0826374bff5741 Michael Lawnick 2010-08-11 386 priv->adap.dev.parent = &parent->dev;
2212a8529eb06c Elie De Brauwer 2013-12-09 387 priv->adap.retries = parent->retries;
2212a8529eb06c Elie De Brauwer 2013-12-09 388 priv->adap.timeout = parent->timeout;
dc362d50ba94ea Alexander Sverdlin 2015-06-12 389 priv->adap.quirks = parent->quirks;
d1ed7985b9a6b8 Peter Rosin 2016-08-25 390 if (muxc->mux_locked)
d1ed7985b9a6b8 Peter Rosin 2016-08-25 391 priv->adap.lock_ops = &i2c_mux_lock_ops;
d1ed7985b9a6b8 Peter Rosin 2016-08-25 392 else
d1ed7985b9a6b8 Peter Rosin 2016-08-25 393 priv->adap.lock_ops = &i2c_parent_lock_ops;
0826374bff5741 Michael Lawnick 2010-08-11 394
bc45449b144461 David Daney 2012-04-12 395 /*
bc45449b144461 David Daney 2012-04-12 396 * Try to populate the mux adapter's of_node, expands to
bc45449b144461 David Daney 2012-04-12 397 * nothing if !CONFIG_OF.
bc45449b144461 David Daney 2012-04-12 398 */
a7ab72390b7706 Peter Rosin 2016-04-20 399 if (muxc->dev->of_node) {
b2d57b56047b99 Peter Rosin 2016-07-09 400 struct device_node *dev_node = muxc->dev->of_node;
b2d57b56047b99 Peter Rosin 2016-07-09 401 struct device_node *mux_node, *child = NULL;
bc45449b144461 David Daney 2012-04-12 402 u32 reg;
bc45449b144461 David Daney 2012-04-12 403
b2d57b56047b99 Peter Rosin 2016-07-09 404 if (muxc->arbitrator)
b2d57b56047b99 Peter Rosin 2016-07-09 405 mux_node = of_get_child_by_name(dev_node, "i2c-arb");
b2d57b56047b99 Peter Rosin 2016-07-09 406 else if (muxc->gate)
b2d57b56047b99 Peter Rosin 2016-07-09 407 mux_node = of_get_child_by_name(dev_node, "i2c-gate");
b2d57b56047b99 Peter Rosin 2016-07-09 408 else
b2d57b56047b99 Peter Rosin 2016-07-09 409 mux_node = of_get_child_by_name(dev_node, "i2c-mux");
b2d57b56047b99 Peter Rosin 2016-07-09 410
b2d57b56047b99 Peter Rosin 2016-07-09 411 if (mux_node) {
b2d57b56047b99 Peter Rosin 2016-07-09 412 /* A "reg" property indicates an old-style DT entry */
b2d57b56047b99 Peter Rosin 2016-07-09 413 if (!of_property_read_u32(mux_node, "reg", ®)) {
b2d57b56047b99 Peter Rosin 2016-07-09 414 of_node_put(mux_node);
b2d57b56047b99 Peter Rosin 2016-07-09 415 mux_node = NULL;
b2d57b56047b99 Peter Rosin 2016-07-09 416 }
b2d57b56047b99 Peter Rosin 2016-07-09 417 }
b2d57b56047b99 Peter Rosin 2016-07-09 418
b2d57b56047b99 Peter Rosin 2016-07-09 419 if (!mux_node)
b2d57b56047b99 Peter Rosin 2016-07-09 420 mux_node = of_node_get(dev_node);
b2d57b56047b99 Peter Rosin 2016-07-09 421 else if (muxc->arbitrator || muxc->gate)
b2d57b56047b99 Peter Rosin 2016-07-09 422 child = of_node_get(mux_node);
b2d57b56047b99 Peter Rosin 2016-07-09 423
b2d57b56047b99 Peter Rosin 2016-07-09 424 if (!child) {
b2d57b56047b99 Peter Rosin 2016-07-09 425 for_each_child_of_node(mux_node, child) {
bc45449b144461 David Daney 2012-04-12 426 ret = of_property_read_u32(child, "reg", ®);
bc45449b144461 David Daney 2012-04-12 427 if (ret)
bc45449b144461 David Daney 2012-04-12 428 continue;
b2d57b56047b99 Peter Rosin 2016-07-09 429 if (chan_id == reg)
bc45449b144461 David Daney 2012-04-12 430 break;
bc45449b144461 David Daney 2012-04-12 431 }
64f0150a54ef60 Marcus Folkesson 2025-10-02 432 }
64f0150a54ef60 Marcus Folkesson 2025-10-02 433
64f0150a54ef60 Marcus Folkesson 2025-10-02 434 of_property_read_u32(child, "clock-frequency", &priv->adap.clock_hz);
64f0150a54ef60 Marcus Folkesson 2025-10-02 435
64f0150a54ef60 Marcus Folkesson 2025-10-02 436 /*
64f0150a54ef60 Marcus Folkesson 2025-10-02 437 * Warn if the mux adapter is not parent-locked as
64f0150a54ef60 Marcus Folkesson 2025-10-02 438 * this may cause issues for some hardware topologies.
64f0150a54ef60 Marcus Folkesson 2025-10-02 439 */
64f0150a54ef60 Marcus Folkesson 2025-10-02 440 if ((priv->adap.clock_hz < parent->clock_hz) && muxc->mux_locked)
64f0150a54ef60 Marcus Folkesson 2025-10-02 441 dev_warn(muxc->dev,
64f0150a54ef60 Marcus Folkesson 2025-10-02 442 "channel %u is slower than parent on a non parent-locked mux\n",
64f0150a54ef60 Marcus Folkesson 2025-10-02 443 chan_id);
64f0150a54ef60 Marcus Folkesson 2025-10-02 444
64f0150a54ef60 Marcus Folkesson 2025-10-02 445 /* If the mux adapter has no clock-frequency property, inherit from parent */
64f0150a54ef60 Marcus Folkesson 2025-10-02 446 if (!priv->adap.clock_hz)
64f0150a54ef60 Marcus Folkesson 2025-10-02 447 priv->adap.clock_hz = parent->clock_hz;
64f0150a54ef60 Marcus Folkesson 2025-10-02 448
64f0150a54ef60 Marcus Folkesson 2025-10-02 449 /* We don't support mux adapters faster than their parent */
64f0150a54ef60 Marcus Folkesson 2025-10-02 450 if (priv->adap.clock_hz > parent->clock_hz) {
64f0150a54ef60 Marcus Folkesson 2025-10-02 451 dev_err(muxc->dev,
64f0150a54ef60 Marcus Folkesson 2025-10-02 452 "channel (%u) is faster (%u) than parent (%u)\n",
64f0150a54ef60 Marcus Folkesson 2025-10-02 453 chan_id, priv->adap.clock_hz, parent->clock_hz);
64f0150a54ef60 Marcus Folkesson 2025-10-02 454
64f0150a54ef60 Marcus Folkesson 2025-10-02 455 of_node_put(mux_node);
64f0150a54ef60 Marcus Folkesson 2025-10-02 456 goto err_free_priv;
ret = -EINVAL;
bc45449b144461 David Daney 2012-04-12 457 }
b2d57b56047b99 Peter Rosin 2016-07-09 458
b2d57b56047b99 Peter Rosin 2016-07-09 459 priv->adap.dev.of_node = child;
b2d57b56047b99 Peter Rosin 2016-07-09 460 of_node_put(mux_node);
bc45449b144461 David Daney 2012-04-12 461 }
bc45449b144461 David Daney 2012-04-12 462
8eb5c87a92c065 Dustin Byford 2015-10-23 463 /*
8eb5c87a92c065 Dustin Byford 2015-10-23 464 * Associate the mux channel with an ACPI node.
8eb5c87a92c065 Dustin Byford 2015-10-23 465 */
a7ab72390b7706 Peter Rosin 2016-04-20 466 if (has_acpi_companion(muxc->dev))
a7ab72390b7706 Peter Rosin 2016-04-20 467 acpi_preset_companion(&priv->adap.dev,
a7ab72390b7706 Peter Rosin 2016-04-20 468 ACPI_COMPANION(muxc->dev),
8eb5c87a92c065 Dustin Byford 2015-10-23 469 chan_id);
8eb5c87a92c065 Dustin Byford 2015-10-23 470
0826374bff5741 Michael Lawnick 2010-08-11 471 if (force_nr) {
0826374bff5741 Michael Lawnick 2010-08-11 472 priv->adap.nr = force_nr;
0826374bff5741 Michael Lawnick 2010-08-11 473 ret = i2c_add_numbered_adapter(&priv->adap);
9fce894d03a98e Peter Rosin 2017-05-15 474 if (ret < 0) {
8d4d159f25a79b Peter Rosin 2017-04-03 475 dev_err(&parent->dev,
8d4d159f25a79b Peter Rosin 2017-04-03 476 "failed to add mux-adapter %u as bus %u (error=%d)\n",
8d4d159f25a79b Peter Rosin 2017-04-03 477 chan_id, force_nr, ret);
9fce894d03a98e Peter Rosin 2017-05-15 478 goto err_free_priv;
9fce894d03a98e Peter Rosin 2017-05-15 479 }
0826374bff5741 Michael Lawnick 2010-08-11 480 } else {
0826374bff5741 Michael Lawnick 2010-08-11 481 ret = i2c_add_adapter(&priv->adap);
9fce894d03a98e Peter Rosin 2017-05-15 482 if (ret < 0) {
8d4d159f25a79b Peter Rosin 2017-04-03 483 dev_err(&parent->dev,
8d4d159f25a79b Peter Rosin 2017-04-03 484 "failed to add mux-adapter %u (error=%d)\n",
8d4d159f25a79b Peter Rosin 2017-04-03 485 chan_id, ret);
9fce894d03a98e Peter Rosin 2017-05-15 486 goto err_free_priv;
0826374bff5741 Michael Lawnick 2010-08-11 487 }
0826374bff5741 Michael Lawnick 2010-08-11 488 }
0826374bff5741 Michael Lawnick 2010-08-11 489
a7ab72390b7706 Peter Rosin 2016-04-20 490 WARN(sysfs_create_link(&priv->adap.dev.kobj, &muxc->dev->kobj,
a7ab72390b7706 Peter Rosin 2016-04-20 491 "mux_device"),
51cf3b0e2a72bb Wolfram Sang 2014-11-13 492 "can't create symlink to mux device\n");
51cf3b0e2a72bb Wolfram Sang 2014-11-13 493
c9449affad2ae0 Gerlando Falauto 2014-11-13 494 snprintf(symlink_name, sizeof(symlink_name), "channel-%u", chan_id);
a7ab72390b7706 Peter Rosin 2016-04-20 495 WARN(sysfs_create_link(&muxc->dev->kobj, &priv->adap.dev.kobj,
a7ab72390b7706 Peter Rosin 2016-04-20 496 symlink_name),
f657c9fe268882 Wolfram Sang 2018-05-21 497 "can't create symlink to channel %u\n", chan_id);
0826374bff5741 Michael Lawnick 2010-08-11 498 dev_info(&parent->dev, "Added multiplexed i2c bus %d\n",
0826374bff5741 Michael Lawnick 2010-08-11 499 i2c_adapter_id(&priv->adap));
0826374bff5741 Michael Lawnick 2010-08-11 500
a7ab72390b7706 Peter Rosin 2016-04-20 501 muxc->adapter[muxc->num_adapters++] = &priv->adap;
a7ab72390b7706 Peter Rosin 2016-04-20 502 return 0;
9fce894d03a98e Peter Rosin 2017-05-15 503
9fce894d03a98e Peter Rosin 2017-05-15 504 err_free_priv:
9fce894d03a98e Peter Rosin 2017-05-15 505 kfree(priv);
9fce894d03a98e Peter Rosin 2017-05-15 @506 return ret;
0826374bff5741 Michael Lawnick 2010-08-11 507 }
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0-DAY CI Kernel Test Service
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