* [PATCH v3 0/8] i2c mux cleanup and locking update
@ 2016-01-08 15:04 Peter Rosin
[not found] ` <1452265496-22475-1-git-send-email-peda-SamgB31n2u5IcsJQ0EH25Q@public.gmane.org>
` (8 more replies)
0 siblings, 9 replies; 15+ messages in thread
From: Peter Rosin @ 2016-01-08 15:04 UTC (permalink / raw)
To: Wolfram Sang
Cc: Peter Rosin, Peter Korsgaard, Guenter Roeck, Jonathan Cameron,
Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald,
Antti Palosaari, Mauro Carvalho Chehab, Rob Herring, Frank Rowand,
Grant Likely, Srinivas Pandruvada, Adriana Reus,
Krzysztof Kozlowski, Hans Verkuil, Nicholas Mc Guire,
Olli Salonen, Peter Rosin, linux-i2c, linux-kernel, linux-iio,
linux-media, devicetree
From: Peter Rosin <peda@axentia.se>
Hi!
[doing a v3 even if there is no "big picture" feedback yet, but
previous versions has bugs that make them harder to test than
needed, and testing is very much desired]
I have a pair of boards with this i2c topology:
GPIO ---| ------ BAT1
| v /
I2C -----+------B---+---- MUX
| \
EEPROM ------ BAT2
(B denotes the boundary between the boards)
The problem with this is that the GPIO controller sits on the same i2c bus
that it MUXes. For pca954x devices this is worked around by using unlocked
transfers when updating the MUX. I have no such luck as the GPIO is a general
purpose IO expander and the MUX is just a random bidirectional MUX, unaware
of the fact that it is muxing an i2c bus, and extending unlocked transfers
into the GPIO subsystem is too ugly to even think about. But the general hw
approach is sane in my opinion, with the number of connections between the
two boards minimized. To put is plainly, I need support for it.
So, I observe that while it is needed to have the i2c bus locked during the
actual MUX update in order to avoid random garbage on the slave side, it
is not strictly a must to have it locked over the whole sequence of a full
select-transfer-deselect operation. The MUX itself needs to be locked, so
transfers to clients behind the mux are serialized, and the MUX needs to be
stable during all i2c traffic (otherwise individual mux slave segments
might see garbage).
This series accomplishes this by adding code to i2c-mux-gpio and
i2c-mux-pinctrl that determines if all involved devices used to update the
mux are controlled by the same root i2c adapter that is muxed. When this
is the case, the select-transfer-deselect operations should be locked
individually to avoid the deadlock. The i2c bus *is* still locked
during muxing, since the muxing happens as part of i2c transfers. This
is true even if the MUX is updated with several transfers to the GPIO (at
least as long as *all* MUX changes are using the i2s master bus). A lock
is added to the mux so that transfers through the mux are serialized.
Concerns:
- The locking is perhaps too complex?
- I worry about the priority inheritance aspect of the adapter lock. When
the transfers behind the mux are divided into select-transfer-deselect all
locked individually, low priority transfers get more chances to interfere
with high priority transfers.
- When doing an i2c_transfer() in_atomic() context or with irqs_disabled(),
there is a higher possibility that the mux is not returned to its idle
state after a failed (-EAGAIN) transfer due to trylock.
- Is the detection of i2c-controlled gpios and pinctrls sane (i.e. the
usage of the new i2c_root_adapter() function in 8/8)?
To summarize the series, there's some i2c-mux infrastructure cleanup work
first (I think that part stands by itself as desireable regardless), the
locking changes are in the last three patches of the series, with the real
meat in 8/8.
PS. needs a bunch of testing, I do not have access to all the involved hw
Changes since v2:
- Fix devm_kfree of a NULL pointer in i2c_mux_reserve_adapters().
- Remove device tree "i2c-controlled" property and determine this by walking
the dev tree instead.
- Fix compile problems with inv_mpu_acpi.c
- Wait with adding the client pointer to patch 2/8 for pca9541 and pca954x.
Changes since v1:
- Allocate mux core and (optional) priv in a combined allocation.
- Kill dev_err messages triggered by memory allocation failure.
- Fix the device specific i2c muxes that I had overlooked.
- Rebase on top of v4.4-rc8 (was based on v4.4-rc6 previously).
- Drop the last two patches in the series.
Cheers,
Peter
Peter Rosin (8):
i2c-mux: add common core data for every mux instance
i2c-mux: move select and deselect ops to i2c_mux_core
i2c-mux: move the slave side adapter management to i2c_mux_core
i2c-mux: remove the mux dev pointer from the mux per channel data
i2c-mux: pinctrl: get rid of the driver private struct device pointer
i2c: allow adapter drivers to override the adapter locking
i2c: muxes always lock the parent adapter
i2c-mux: relax locking of the top i2c adapter during i2c controlled
muxing
drivers/i2c/i2c-core.c | 59 +++---
drivers/i2c/i2c-mux.c | 299 ++++++++++++++++++++++-----
drivers/i2c/muxes/i2c-arb-gpio-challenge.c | 46 ++---
drivers/i2c/muxes/i2c-mux-gpio.c | 74 ++++---
drivers/i2c/muxes/i2c-mux-pca9541.c | 58 +++---
drivers/i2c/muxes/i2c-mux-pca954x.c | 66 +++---
drivers/i2c/muxes/i2c-mux-pinctrl.c | 125 ++++++-----
drivers/i2c/muxes/i2c-mux-reg.c | 63 +++---
drivers/iio/imu/inv_mpu6050/inv_mpu_acpi.c | 2 +-
drivers/iio/imu/inv_mpu6050/inv_mpu_core.c | 34 +--
drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h | 3 +-
drivers/media/dvb-frontends/m88ds3103.c | 23 ++-
drivers/media/dvb-frontends/m88ds3103_priv.h | 2 +-
drivers/media/dvb-frontends/rtl2830.c | 24 ++-
drivers/media/dvb-frontends/rtl2830_priv.h | 2 +-
drivers/media/dvb-frontends/rtl2832.c | 30 +--
drivers/media/dvb-frontends/rtl2832_priv.h | 2 +-
drivers/media/dvb-frontends/si2168.c | 29 ++-
drivers/media/dvb-frontends/si2168_priv.h | 2 +-
drivers/media/usb/cx231xx/cx231xx-core.c | 6 +-
drivers/media/usb/cx231xx/cx231xx-i2c.c | 48 ++---
drivers/media/usb/cx231xx/cx231xx.h | 4 +-
drivers/of/unittest.c | 41 ++--
include/linux/i2c-mux.h | 41 +++-
include/linux/i2c.h | 28 ++-
25 files changed, 685 insertions(+), 426 deletions(-)
--
2.1.4
^ permalink raw reply [flat|nested] 15+ messages in thread
* [PATCH v3 1/8] i2c-mux: add common core data for every mux instance
[not found] ` <1452265496-22475-1-git-send-email-peda-SamgB31n2u5IcsJQ0EH25Q@public.gmane.org>
@ 2016-01-08 15:04 ` Peter Rosin
0 siblings, 0 replies; 15+ messages in thread
From: Peter Rosin @ 2016-01-08 15:04 UTC (permalink / raw)
To: Wolfram Sang
Cc: Peter Rosin, Peter Korsgaard, Guenter Roeck, Jonathan Cameron,
Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald,
Antti Palosaari, Mauro Carvalho Chehab, Rob Herring, Frank Rowand,
Grant Likely, Srinivas Pandruvada, Adriana Reus,
Krzysztof Kozlowski, Hans Verkuil, Nicholas Mc Guire,
Olli Salonen, Peter Rosin, linux-i2c-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA,
linux-iio-u79uwXL29TY76Z2rM5mHXA,
linux-media-u79uwXL29TY76Z2rM5mHXA, devicetree-u79uwXL29TY
From: Peter Rosin <peda-koto5C5qi+TLoDKTGw+V6w@public.gmane.org>
The initial core mux structure starts off small with only the parent
adapter pointer, which all muxes have, and a priv pointer for mux
driver private data.
Add i2c_mux_alloc function to unify the creation of a mux.
Where appropriate, pass around the mux core structure instead of the
parent adapter or the driver private data.
Remove the parent adapter pointer from the driver private data for all
mux drivers.
Signed-off-by: Peter Rosin <peda-koto5C5qi+TLoDKTGw+V6w@public.gmane.org>
---
drivers/i2c/i2c-mux.c | 28 ++++++++++++++++++-----
drivers/i2c/muxes/i2c-arb-gpio-challenge.c | 24 ++++++++++----------
drivers/i2c/muxes/i2c-mux-gpio.c | 20 ++++++++---------
drivers/i2c/muxes/i2c-mux-pca9541.c | 33 +++++++++++++---------------
drivers/i2c/muxes/i2c-mux-pca954x.c | 17 +++++++++-----
drivers/i2c/muxes/i2c-mux-pinctrl.c | 23 +++++++++----------
drivers/i2c/muxes/i2c-mux-reg.c | 23 ++++++++++---------
drivers/iio/imu/inv_mpu6050/inv_mpu_core.c | 10 ++++++++-
drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h | 1 +
drivers/media/dvb-frontends/m88ds3103.c | 10 ++++++++-
drivers/media/dvb-frontends/m88ds3103_priv.h | 1 +
drivers/media/dvb-frontends/rtl2830.c | 10 ++++++++-
drivers/media/dvb-frontends/rtl2830_priv.h | 1 +
drivers/media/dvb-frontends/rtl2832.c | 10 ++++++++-
drivers/media/dvb-frontends/rtl2832_priv.h | 1 +
drivers/media/dvb-frontends/si2168.c | 10 ++++++++-
drivers/media/dvb-frontends/si2168_priv.h | 1 +
drivers/media/usb/cx231xx/cx231xx-core.c | 3 +++
drivers/media/usb/cx231xx/cx231xx-i2c.c | 13 +++++++++--
drivers/media/usb/cx231xx/cx231xx.h | 2 ++
drivers/of/unittest.c | 16 ++++++++------
include/linux/i2c-mux.h | 14 +++++++++++-
22 files changed, 183 insertions(+), 88 deletions(-)
diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c
index 00fc5b1c7b66..c2163f6b51d5 100644
--- a/drivers/i2c/i2c-mux.c
+++ b/drivers/i2c/i2c-mux.c
@@ -31,8 +31,8 @@
struct i2c_mux_priv {
struct i2c_adapter adap;
struct i2c_algorithm algo;
+ struct i2c_mux_core *muxc;
- struct i2c_adapter *parent;
struct device *mux_dev;
void *mux_priv;
u32 chan_id;
@@ -45,7 +45,8 @@ static int i2c_mux_master_xfer(struct i2c_adapter *adap,
struct i2c_msg msgs[], int num)
{
struct i2c_mux_priv *priv = adap->algo_data;
- struct i2c_adapter *parent = priv->parent;
+ struct i2c_mux_core *muxc = priv->muxc;
+ struct i2c_adapter *parent = muxc->parent;
int ret;
/* Switch to the right mux port and perform the transfer. */
@@ -65,7 +66,8 @@ static int i2c_mux_smbus_xfer(struct i2c_adapter *adap,
int size, union i2c_smbus_data *data)
{
struct i2c_mux_priv *priv = adap->algo_data;
- struct i2c_adapter *parent = priv->parent;
+ struct i2c_mux_core *muxc = priv->muxc;
+ struct i2c_adapter *parent = muxc->parent;
int ret;
/* Select the right mux port and perform the transfer. */
@@ -84,7 +86,7 @@ static int i2c_mux_smbus_xfer(struct i2c_adapter *adap,
static u32 i2c_mux_functionality(struct i2c_adapter *adap)
{
struct i2c_mux_priv *priv = adap->algo_data;
- struct i2c_adapter *parent = priv->parent;
+ struct i2c_adapter *parent = priv->muxc->parent;
return parent->algo->functionality(parent);
}
@@ -102,7 +104,20 @@ static unsigned int i2c_mux_parent_classes(struct i2c_adapter *parent)
return class;
}
-struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
+struct i2c_mux_core *i2c_mux_alloc(struct device *dev, int sizeof_priv)
+{
+ struct i2c_mux_core *muxc;
+
+ muxc = devm_kzalloc(dev, sizeof(*muxc) + sizeof_priv, GFP_KERNEL);
+ if (!muxc)
+ return NULL;
+ if (sizeof_priv)
+ muxc->priv = muxc + 1;
+ return muxc;
+}
+EXPORT_SYMBOL_GPL(i2c_mux_alloc);
+
+struct i2c_adapter *i2c_add_mux_adapter(struct i2c_mux_core *muxc,
struct device *mux_dev,
void *mux_priv, u32 force_nr, u32 chan_id,
unsigned int class,
@@ -111,6 +126,7 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
int (*deselect) (struct i2c_adapter *,
void *, u32))
{
+ struct i2c_adapter *parent = muxc->parent;
struct i2c_mux_priv *priv;
char symlink_name[20];
int ret;
@@ -120,7 +136,7 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
return NULL;
/* Set up private adapter data */
- priv->parent = parent;
+ priv->muxc = muxc;
priv->mux_dev = mux_dev;
priv->mux_priv = mux_priv;
priv->chan_id = chan_id;
diff --git a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
index 402e3a6c671a..6e27ea4fb25a 100644
--- a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
+++ b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
@@ -42,7 +42,6 @@
*/
struct i2c_arbitrator_data {
- struct i2c_adapter *parent;
struct i2c_adapter *child;
int our_gpio;
int our_gpio_release;
@@ -119,6 +118,7 @@ static int i2c_arbitrator_probe(struct platform_device *pdev)
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct device_node *parent_np;
+ struct i2c_mux_core *muxc;
struct i2c_arbitrator_data *arb;
enum of_gpio_flags gpio_flags;
unsigned long out_init;
@@ -134,13 +134,12 @@ static int i2c_arbitrator_probe(struct platform_device *pdev)
return -EINVAL;
}
- arb = devm_kzalloc(dev, sizeof(*arb), GFP_KERNEL);
- if (!arb) {
- dev_err(dev, "Cannot allocate i2c_arbitrator_data\n");
+ muxc = i2c_mux_alloc(dev, sizeof(*arb));
+ if (!muxc)
return -ENOMEM;
- }
- platform_set_drvdata(pdev, arb);
+ arb = i2c_mux_priv(muxc);
+ platform_set_drvdata(pdev, muxc);
/* Request GPIOs */
ret = of_get_named_gpio_flags(np, "our-claim-gpio", 0, &gpio_flags);
if (!gpio_is_valid(ret)) {
@@ -196,21 +195,21 @@ static int i2c_arbitrator_probe(struct platform_device *pdev)
dev_err(dev, "Cannot parse i2c-parent\n");
return -EINVAL;
}
- arb->parent = of_get_i2c_adapter_by_node(parent_np);
+ muxc->parent = of_find_i2c_adapter_by_node(parent_np);
of_node_put(parent_np);
- if (!arb->parent) {
+ if (!muxc->parent) {
dev_err(dev, "Cannot find parent bus\n");
return -EPROBE_DEFER;
}
/* Actually add the mux adapter */
- arb->child = i2c_add_mux_adapter(arb->parent, dev, arb, 0, 0, 0,
+ arb->child = i2c_add_mux_adapter(muxc, dev, arb, 0, 0, 0,
i2c_arbitrator_select,
i2c_arbitrator_deselect);
if (!arb->child) {
dev_err(dev, "Failed to add adapter\n");
ret = -ENODEV;
- i2c_put_adapter(arb->parent);
+ i2c_put_adapter(muxc->parent);
}
return ret;
@@ -218,10 +217,11 @@ static int i2c_arbitrator_probe(struct platform_device *pdev)
static int i2c_arbitrator_remove(struct platform_device *pdev)
{
- struct i2c_arbitrator_data *arb = platform_get_drvdata(pdev);
+ struct i2c_mux_core *muxc = platform_get_drvdata(pdev);
+ struct i2c_arbitrator_data *arb = i2c_mux_priv(muxc);
i2c_del_mux_adapter(arb->child);
- i2c_put_adapter(arb->parent);
+ i2c_put_adapter(muxc->parent);
return 0;
}
diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
index b8e11c16d98c..ee43dd76a4d7 100644
--- a/drivers/i2c/muxes/i2c-mux-gpio.c
+++ b/drivers/i2c/muxes/i2c-mux-gpio.c
@@ -18,7 +18,6 @@
#include <linux/of_gpio.h>
struct gpiomux {
- struct i2c_adapter *parent;
struct i2c_adapter **adap; /* child busses */
struct i2c_mux_gpio_platform_data data;
unsigned gpio_base;
@@ -136,19 +135,19 @@ static int i2c_mux_gpio_probe_dt(struct gpiomux *mux,
static int i2c_mux_gpio_probe(struct platform_device *pdev)
{
+ struct i2c_mux_core *muxc;
struct gpiomux *mux;
struct i2c_adapter *parent;
int (*deselect) (struct i2c_adapter *, void *, u32);
unsigned initial_state, gpio_base;
int i, ret;
- mux = devm_kzalloc(&pdev->dev, sizeof(*mux), GFP_KERNEL);
- if (!mux) {
- dev_err(&pdev->dev, "Cannot allocate gpiomux structure");
+ muxc = i2c_mux_alloc(&pdev->dev, sizeof(*mux));
+ if (!muxc)
return -ENOMEM;
- }
+ mux = i2c_mux_priv(muxc);
- platform_set_drvdata(pdev, mux);
+ platform_set_drvdata(pdev, muxc);
if (!dev_get_platdata(&pdev->dev)) {
ret = i2c_mux_gpio_probe_dt(mux, pdev);
@@ -180,7 +179,7 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
if (!parent)
return -EPROBE_DEFER;
- mux->parent = parent;
+ muxc->parent = parent;
mux->gpio_base = gpio_base;
mux->adap = devm_kzalloc(&pdev->dev,
@@ -223,7 +222,7 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
u32 nr = mux->data.base_nr ? (mux->data.base_nr + i) : 0;
unsigned int class = mux->data.classes ? mux->data.classes[i] : 0;
- mux->adap[i] = i2c_add_mux_adapter(parent, &pdev->dev, mux, nr,
+ mux->adap[i] = i2c_add_mux_adapter(muxc, &pdev->dev, mux, nr,
mux->data.values[i], class,
i2c_mux_gpio_select, deselect);
if (!mux->adap[i]) {
@@ -253,7 +252,8 @@ alloc_failed:
static int i2c_mux_gpio_remove(struct platform_device *pdev)
{
- struct gpiomux *mux = platform_get_drvdata(pdev);
+ struct i2c_mux_core *muxc = platform_get_drvdata(pdev);
+ struct gpiomux *mux = i2c_mux_priv(muxc);
int i;
for (i = 0; i < mux->data.n_values; i++)
@@ -262,7 +262,7 @@ static int i2c_mux_gpio_remove(struct platform_device *pdev)
for (i = 0; i < mux->data.n_gpios; i++)
gpio_free(mux->gpio_base + mux->data.gpios[i]);
- i2c_put_adapter(mux->parent);
+ i2c_put_adapter(muxc->parent);
return 0;
}
diff --git a/drivers/i2c/muxes/i2c-mux-pca9541.c b/drivers/i2c/muxes/i2c-mux-pca9541.c
index d0ba424adebc..78648d1263bc 100644
--- a/drivers/i2c/muxes/i2c-mux-pca9541.c
+++ b/drivers/i2c/muxes/i2c-mux-pca9541.c
@@ -217,7 +217,8 @@ static const u8 pca9541_control[16] = {
*/
static int pca9541_arbitrate(struct i2c_client *client)
{
- struct pca9541 *data = i2c_get_clientdata(client);
+ struct i2c_mux_core *muxc = i2c_get_clientdata(client);
+ struct pca9541 *data = i2c_mux_priv(muxc);
int reg;
reg = pca9541_reg_read(client, PCA9541_CONTROL);
@@ -324,20 +325,21 @@ static int pca9541_probe(struct i2c_client *client,
{
struct i2c_adapter *adap = client->adapter;
struct pca954x_platform_data *pdata = dev_get_platdata(&client->dev);
+ struct i2c_mux_core *muxc;
struct pca9541 *data;
int force;
- int ret = -ENODEV;
if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_BYTE_DATA))
- goto err;
+ return -ENODEV;
- data = kzalloc(sizeof(struct pca9541), GFP_KERNEL);
- if (!data) {
- ret = -ENOMEM;
- goto err;
- }
+ muxc = i2c_mux_alloc(&client->dev, sizeof(*data));
+ if (!muxc)
+ return -ENOMEM;
+ data = i2c_mux_priv(muxc);
+
+ i2c_set_clientdata(client, muxc);
- i2c_set_clientdata(client, data);
+ muxc->parent = adap;
/*
* I2C accesses are unprotected here.
@@ -352,34 +354,29 @@ static int pca9541_probe(struct i2c_client *client,
force = 0;
if (pdata)
force = pdata->modes[0].adap_id;
- data->mux_adap = i2c_add_mux_adapter(adap, &client->dev, client,
+ data->mux_adap = i2c_add_mux_adapter(muxc, &client->dev, client,
force, 0, 0,
pca9541_select_chan,
pca9541_release_chan);
if (data->mux_adap == NULL) {
dev_err(&client->dev, "failed to register master selector\n");
- goto exit_free;
+ return -ENODEV;
}
dev_info(&client->dev, "registered master selector for I2C %s\n",
client->name);
return 0;
-
-exit_free:
- kfree(data);
-err:
- return ret;
}
static int pca9541_remove(struct i2c_client *client)
{
- struct pca9541 *data = i2c_get_clientdata(client);
+ struct i2c_mux_core *muxc = i2c_get_clientdata(client);
+ struct pca9541 *data = i2c_mux_priv(muxc);
i2c_del_mux_adapter(data->mux_adap);
- kfree(data);
return 0;
}
diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
index acfcef3d4068..acc2f87fe321 100644
--- a/drivers/i2c/muxes/i2c-mux-pca954x.c
+++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
@@ -191,17 +191,19 @@ static int pca954x_probe(struct i2c_client *client,
bool idle_disconnect_dt;
struct gpio_desc *gpio;
int num, force, class;
+ struct i2c_mux_core *muxc;
struct pca954x *data;
int ret;
if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_BYTE))
return -ENODEV;
- data = devm_kzalloc(&client->dev, sizeof(struct pca954x), GFP_KERNEL);
- if (!data)
+ muxc = i2c_mux_alloc(&client->dev, sizeof(*data));
+ if (!muxc)
return -ENOMEM;
+ data = i2c_mux_priv(muxc);
- i2c_set_clientdata(client, data);
+ i2c_set_clientdata(client, muxc);
/* Get the mux out of reset if a reset GPIO is specified. */
gpio = devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_LOW);
@@ -217,6 +219,7 @@ static int pca954x_probe(struct i2c_client *client,
return -ENODEV;
}
+ muxc->parent = adap;
data->type = id->driver_data;
data->last_chan = 0; /* force the first selection */
@@ -241,7 +244,7 @@ static int pca954x_probe(struct i2c_client *client,
}
data->virt_adaps[num] =
- i2c_add_mux_adapter(adap, &client->dev, client,
+ i2c_add_mux_adapter(muxc, &client->dev, client,
force, num, class, pca954x_select_chan,
(idle_disconnect_pd || idle_disconnect_dt)
? pca954x_deselect_mux : NULL);
@@ -270,7 +273,8 @@ virt_reg_failed:
static int pca954x_remove(struct i2c_client *client)
{
- struct pca954x *data = i2c_get_clientdata(client);
+ struct i2c_mux_core *muxc = i2c_get_clientdata(client);
+ struct pca954x *data = i2c_mux_priv(muxc);
const struct chip_desc *chip = &chips[data->type];
int i;
@@ -287,7 +291,8 @@ static int pca954x_remove(struct i2c_client *client)
static int pca954x_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
- struct pca954x *data = i2c_get_clientdata(client);
+ struct i2c_mux_core *muxc = i2c_get_clientdata(client);
+ struct pca954x *data = i2c_mux_priv(muxc);
data->last_chan = 0;
return i2c_smbus_write_byte(client, 0);
diff --git a/drivers/i2c/muxes/i2c-mux-pinctrl.c b/drivers/i2c/muxes/i2c-mux-pinctrl.c
index b5a982ba8898..810f75f114a7 100644
--- a/drivers/i2c/muxes/i2c-mux-pinctrl.c
+++ b/drivers/i2c/muxes/i2c-mux-pinctrl.c
@@ -31,7 +31,6 @@ struct i2c_mux_pinctrl {
struct pinctrl *pinctrl;
struct pinctrl_state **states;
struct pinctrl_state *state_idle;
- struct i2c_adapter *parent;
struct i2c_adapter **busses;
};
@@ -131,17 +130,18 @@ static inline int i2c_mux_pinctrl_parse_dt(struct i2c_mux_pinctrl *mux,
static int i2c_mux_pinctrl_probe(struct platform_device *pdev)
{
+ struct i2c_mux_core *muxc;
struct i2c_mux_pinctrl *mux;
int (*deselect)(struct i2c_adapter *, void *, u32);
int i, ret;
- mux = devm_kzalloc(&pdev->dev, sizeof(*mux), GFP_KERNEL);
- if (!mux) {
- dev_err(&pdev->dev, "Cannot allocate i2c_mux_pinctrl\n");
+ muxc = i2c_mux_alloc(&pdev->dev, sizeof(*mux));
+ if (!muxc) {
ret = -ENOMEM;
goto err;
}
- platform_set_drvdata(pdev, mux);
+ mux = i2c_mux_priv(muxc);
+ platform_set_drvdata(pdev, muxc);
mux->dev = &pdev->dev;
@@ -208,8 +208,8 @@ static int i2c_mux_pinctrl_probe(struct platform_device *pdev)
deselect = NULL;
}
- mux->parent = i2c_get_adapter(mux->pdata->parent_bus_num);
- if (!mux->parent) {
+ muxc->parent = i2c_get_adapter(mux->pdata->parent_bus_num);
+ if (!muxc->parent) {
dev_err(&pdev->dev, "Parent adapter (%d) not found\n",
mux->pdata->parent_bus_num);
ret = -EPROBE_DEFER;
@@ -220,7 +220,7 @@ static int i2c_mux_pinctrl_probe(struct platform_device *pdev)
u32 bus = mux->pdata->base_bus_num ?
(mux->pdata->base_bus_num + i) : 0;
- mux->busses[i] = i2c_add_mux_adapter(mux->parent, &pdev->dev,
+ mux->busses[i] = i2c_add_mux_adapter(muxc, &pdev->dev,
mux, bus, i, 0,
i2c_mux_pinctrl_select,
deselect);
@@ -236,20 +236,21 @@ static int i2c_mux_pinctrl_probe(struct platform_device *pdev)
err_del_adapter:
for (; i > 0; i--)
i2c_del_mux_adapter(mux->busses[i - 1]);
- i2c_put_adapter(mux->parent);
+ i2c_put_adapter(muxc->parent);
err:
return ret;
}
static int i2c_mux_pinctrl_remove(struct platform_device *pdev)
{
- struct i2c_mux_pinctrl *mux = platform_get_drvdata(pdev);
+ struct i2c_mux_core *muxc = platform_get_drvdata(pdev);
+ struct i2c_mux_pinctrl *mux = i2c_mux_priv(muxc);
int i;
for (i = 0; i < mux->pdata->bus_count; i++)
i2c_del_mux_adapter(mux->busses[i]);
- i2c_put_adapter(mux->parent);
+ i2c_put_adapter(muxc->parent);
return 0;
}
diff --git a/drivers/i2c/muxes/i2c-mux-reg.c b/drivers/i2c/muxes/i2c-mux-reg.c
index 5fbd5bd0878f..8bde4cfac512 100644
--- a/drivers/i2c/muxes/i2c-mux-reg.c
+++ b/drivers/i2c/muxes/i2c-mux-reg.c
@@ -21,7 +21,6 @@
#include <linux/slab.h>
struct regmux {
- struct i2c_adapter *parent;
struct i2c_adapter **adap; /* child busses */
struct i2c_mux_reg_platform_data data;
};
@@ -87,6 +86,7 @@ static int i2c_mux_reg_deselect(struct i2c_adapter *adap, void *data,
static int i2c_mux_reg_probe_dt(struct regmux *mux,
struct platform_device *pdev)
{
+ struct i2c_mux_core *muxc = platform_get_drvdata(pdev);
struct device_node *np = pdev->dev.of_node;
struct device_node *adapter_np, *child;
struct i2c_adapter *adapter;
@@ -107,7 +107,7 @@ static int i2c_mux_reg_probe_dt(struct regmux *mux,
if (!adapter)
return -EPROBE_DEFER;
- mux->parent = adapter;
+ muxc->parent = adapter;
mux->data.parent = i2c_adapter_id(adapter);
put_device(&adapter->dev);
@@ -169,6 +169,7 @@ static int i2c_mux_reg_probe_dt(struct regmux *mux,
static int i2c_mux_reg_probe(struct platform_device *pdev)
{
+ struct i2c_mux_core *muxc;
struct regmux *mux;
struct i2c_adapter *parent;
struct resource *res;
@@ -176,11 +177,12 @@ static int i2c_mux_reg_probe(struct platform_device *pdev)
unsigned int class;
int i, ret, nr;
- mux = devm_kzalloc(&pdev->dev, sizeof(*mux), GFP_KERNEL);
- if (!mux)
+ muxc = i2c_mux_alloc(&pdev->dev, sizeof(*mux));
+ if (!muxc)
return -ENOMEM;
+ mux = i2c_mux_priv(muxc);
- platform_set_drvdata(pdev, mux);
+ platform_set_drvdata(pdev, muxc);
if (dev_get_platdata(&pdev->dev)) {
memcpy(&mux->data, dev_get_platdata(&pdev->dev),
@@ -190,7 +192,7 @@ static int i2c_mux_reg_probe(struct platform_device *pdev)
if (!parent)
return -EPROBE_DEFER;
- mux->parent = parent;
+ muxc->parent = parent;
} else {
ret = i2c_mux_reg_probe_dt(mux, pdev);
if (ret < 0) {
@@ -232,7 +234,7 @@ static int i2c_mux_reg_probe(struct platform_device *pdev)
nr = mux->data.base_nr ? (mux->data.base_nr + i) : 0;
class = mux->data.classes ? mux->data.classes[i] : 0;
- mux->adap[i] = i2c_add_mux_adapter(mux->parent, &pdev->dev, mux,
+ mux->adap[i] = i2c_add_mux_adapter(muxc, &pdev->dev, mux,
nr, mux->data.values[i],
class, i2c_mux_reg_select,
deselect);
@@ -244,7 +246,7 @@ static int i2c_mux_reg_probe(struct platform_device *pdev)
}
dev_dbg(&pdev->dev, "%d port mux on %s adapter\n",
- mux->data.n_values, mux->parent->name);
+ mux->data.n_values, muxc->parent->name);
return 0;
@@ -257,13 +259,14 @@ add_adapter_failed:
static int i2c_mux_reg_remove(struct platform_device *pdev)
{
- struct regmux *mux = platform_get_drvdata(pdev);
+ struct i2c_mux_core *muxc = platform_get_drvdata(pdev);
+ struct regmux *mux = i2c_mux_priv(muxc);
int i;
for (i = 0; i < mux->data.n_values; i++)
i2c_del_mux_adapter(mux->adap[i]);
- i2c_put_adapter(mux->parent);
+ i2c_put_adapter(muxc->parent);
return 0;
}
diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
index f0e06093b5e8..3aab0d7a1bdc 100644
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
@@ -842,7 +842,15 @@ static int inv_mpu_probe(struct i2c_client *client,
goto out_remove_trigger;
}
- st->mux_adapter = i2c_add_mux_adapter(client->adapter,
+ st->muxc = i2c_mux_alloc(&client->dev, 0);
+ if (!st->muxc) {
+ result = -ENOMEM;
+ goto out_unreg_device;
+ }
+ st->muxc->priv = indio_dev;
+ st->muxc->parent = client->adapter;
+
+ st->mux_adapter = i2c_add_mux_adapter(st->muxc,
&client->dev,
indio_dev,
0, 0, 0,
diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
index db0a4a2758ab..d4929db4b40e 100644
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
@@ -120,6 +120,7 @@ struct inv_mpu6050_state {
enum inv_devices chip_type;
spinlock_t time_stamp_lock;
struct i2c_client *client;
+ struct i2c_mux_core *muxc;
struct i2c_adapter *mux_adapter;
struct i2c_client *mux_client;
unsigned int powerup_count;
diff --git a/drivers/media/dvb-frontends/m88ds3103.c b/drivers/media/dvb-frontends/m88ds3103.c
index feeeb70d841e..a0006aec6937 100644
--- a/drivers/media/dvb-frontends/m88ds3103.c
+++ b/drivers/media/dvb-frontends/m88ds3103.c
@@ -1466,8 +1466,16 @@ static int m88ds3103_probe(struct i2c_client *client,
if (ret)
goto err_kfree;
+ dev->muxc = i2c_mux_alloc(&client->dev, 0);
+ if (!dev->muxc) {
+ ret = -ENOMEM;
+ goto err_kfree;
+ }
+ dev->muxc->priv = dev;
+ dev->muxc->parent = client->adapter;
+
/* create mux i2c adapter for tuner */
- dev->i2c_adapter = i2c_add_mux_adapter(client->adapter, &client->dev,
+ dev->i2c_adapter = i2c_add_mux_adapter(dev->muxc, &client->dev,
dev, 0, 0, 0, m88ds3103_select,
NULL);
if (dev->i2c_adapter == NULL) {
diff --git a/drivers/media/dvb-frontends/m88ds3103_priv.h b/drivers/media/dvb-frontends/m88ds3103_priv.h
index eee8c22c51ec..52d66c566ac1 100644
--- a/drivers/media/dvb-frontends/m88ds3103_priv.h
+++ b/drivers/media/dvb-frontends/m88ds3103_priv.h
@@ -42,6 +42,7 @@ struct m88ds3103_dev {
enum fe_status fe_status;
u32 dvbv3_ber; /* for old DVBv3 API read_ber */
bool warm; /* FW running */
+ struct i2c_mux_core *muxc;
struct i2c_adapter *i2c_adapter;
/* auto detect chip id to do different config */
u8 chip_id;
diff --git a/drivers/media/dvb-frontends/rtl2830.c b/drivers/media/dvb-frontends/rtl2830.c
index b792f305cf15..ebf28b49cab2 100644
--- a/drivers/media/dvb-frontends/rtl2830.c
+++ b/drivers/media/dvb-frontends/rtl2830.c
@@ -864,8 +864,16 @@ static int rtl2830_probe(struct i2c_client *client,
if (ret)
goto err_regmap_exit;
+ dev->muxc = i2c_mux_alloc(&client->dev, 0);
+ if (!dev->muxc) {
+ ret = -ENOMEM;
+ goto err_regmap_exit;
+ }
+ dev->muxc->priv = client;
+ dev->muxc->parent = client->adapter;
+
/* create muxed i2c adapter for tuner */
- dev->adapter = i2c_add_mux_adapter(client->adapter, &client->dev,
+ dev->adapter = i2c_add_mux_adapter(dev->muxc, &client->dev,
client, 0, 0, 0, rtl2830_select, NULL);
if (dev->adapter == NULL) {
ret = -ENODEV;
diff --git a/drivers/media/dvb-frontends/rtl2830_priv.h b/drivers/media/dvb-frontends/rtl2830_priv.h
index cf793f39a09b..2169c8d9c99c 100644
--- a/drivers/media/dvb-frontends/rtl2830_priv.h
+++ b/drivers/media/dvb-frontends/rtl2830_priv.h
@@ -29,6 +29,7 @@ struct rtl2830_dev {
struct rtl2830_platform_data *pdata;
struct i2c_client *client;
struct regmap *regmap;
+ struct i2c_mux_core *muxc;
struct i2c_adapter *adapter;
struct dvb_frontend fe;
bool sleeping;
diff --git a/drivers/media/dvb-frontends/rtl2832.c b/drivers/media/dvb-frontends/rtl2832.c
index 78b87b260d74..38402ad3ecdd 100644
--- a/drivers/media/dvb-frontends/rtl2832.c
+++ b/drivers/media/dvb-frontends/rtl2832.c
@@ -1261,8 +1261,16 @@ static int rtl2832_probe(struct i2c_client *client,
if (ret)
goto err_regmap_exit;
+ dev->muxc = i2c_mux_alloc(&client->dev, 0);
+ if (!dev->muxc) {
+ ret = -ENOMEM;
+ goto err_regmap_exit;
+ }
+ dev->muxc->priv = dev;
+ dev->muxc->parent = i2c;
+
/* create muxed i2c adapter for demod tuner bus */
- dev->i2c_adapter_tuner = i2c_add_mux_adapter(i2c, &i2c->dev, dev,
+ dev->i2c_adapter_tuner = i2c_add_mux_adapter(dev->muxc, &i2c->dev, dev,
0, 0, 0, rtl2832_select, rtl2832_deselect);
if (dev->i2c_adapter_tuner == NULL) {
ret = -ENODEV;
diff --git a/drivers/media/dvb-frontends/rtl2832_priv.h b/drivers/media/dvb-frontends/rtl2832_priv.h
index 5dcd3a41d23f..2d252bd5b8b1 100644
--- a/drivers/media/dvb-frontends/rtl2832_priv.h
+++ b/drivers/media/dvb-frontends/rtl2832_priv.h
@@ -36,6 +36,7 @@ struct rtl2832_dev {
struct mutex regmap_mutex;
struct regmap_config regmap_config;
struct regmap *regmap;
+ struct i2c_mux_core *muxc;
struct i2c_adapter *i2c_adapter_tuner;
struct dvb_frontend fe;
struct delayed_work stat_work;
diff --git a/drivers/media/dvb-frontends/si2168.c b/drivers/media/dvb-frontends/si2168.c
index 821a8f481507..a52756bf9834 100644
--- a/drivers/media/dvb-frontends/si2168.c
+++ b/drivers/media/dvb-frontends/si2168.c
@@ -708,8 +708,16 @@ static int si2168_probe(struct i2c_client *client,
goto err;
}
+ dev->muxc = i2c_mux_alloc(&client->dev, 0);
+ if (!dev->muxc) {
+ ret = -ENOMEM;
+ goto err_kfree;
+ }
+ dev->muxc->priv = client;
+ dev->muxc->parent = client->adapter;
+
/* create mux i2c adapter for tuner */
- dev->adapter = i2c_add_mux_adapter(client->adapter, &client->dev,
+ dev->adapter = i2c_add_mux_adapter(dev->muxc, &client->dev,
client, 0, 0, 0, si2168_select, si2168_deselect);
if (dev->adapter == NULL) {
ret = -ENODEV;
diff --git a/drivers/media/dvb-frontends/si2168_priv.h b/drivers/media/dvb-frontends/si2168_priv.h
index c07e6fe2cb10..53efb9d562da 100644
--- a/drivers/media/dvb-frontends/si2168_priv.h
+++ b/drivers/media/dvb-frontends/si2168_priv.h
@@ -29,6 +29,7 @@
/* state struct */
struct si2168_dev {
+ struct i2c_mux_core *muxc;
struct i2c_adapter *adapter;
struct dvb_frontend fe;
enum fe_delivery_system delivery_system;
diff --git a/drivers/media/usb/cx231xx/cx231xx-core.c b/drivers/media/usb/cx231xx/cx231xx-core.c
index a2fd49b6be83..d805e192e4ca 100644
--- a/drivers/media/usb/cx231xx/cx231xx-core.c
+++ b/drivers/media/usb/cx231xx/cx231xx-core.c
@@ -1291,6 +1291,9 @@ int cx231xx_dev_init(struct cx231xx *dev)
cx231xx_i2c_register(&dev->i2c_bus[1]);
cx231xx_i2c_register(&dev->i2c_bus[2]);
+ errCode = cx231xx_i2c_mux_create(dev);
+ if (errCode < 0)
+ return errCode;
cx231xx_i2c_mux_register(dev, 0);
cx231xx_i2c_mux_register(dev, 1);
diff --git a/drivers/media/usb/cx231xx/cx231xx-i2c.c b/drivers/media/usb/cx231xx/cx231xx-i2c.c
index a29c345b027d..09c30e753ca5 100644
--- a/drivers/media/usb/cx231xx/cx231xx-i2c.c
+++ b/drivers/media/usb/cx231xx/cx231xx-i2c.c
@@ -565,13 +565,22 @@ static int cx231xx_i2c_mux_select(struct i2c_adapter *adap,
return cx231xx_enable_i2c_port_3(dev, chan_id);
}
+int cx231xx_i2c_mux_create(struct cx231xx *dev)
+{
+ dev->muxc = i2c_mux_alloc(dev->dev, 0);
+ if (!dev->muxc)
+ return -ENOMEM;
+ dev->muxc->priv = dev;
+ dev->muxc->parent = &dev->i2c_bus[1].i2c_adap;
+ return 0;
+}
+
int cx231xx_i2c_mux_register(struct cx231xx *dev, int mux_no)
{
- struct i2c_adapter *i2c_parent = &dev->i2c_bus[1].i2c_adap;
/* what is the correct mux_dev? */
struct device *mux_dev = dev->dev;
- dev->i2c_mux_adap[mux_no] = i2c_add_mux_adapter(i2c_parent,
+ dev->i2c_mux_adap[mux_no] = i2c_add_mux_adapter(dev->muxc,
mux_dev,
dev /* mux_priv */,
0,
diff --git a/drivers/media/usb/cx231xx/cx231xx.h b/drivers/media/usb/cx231xx/cx231xx.h
index 54790fbe8fdc..72f8188e0b01 100644
--- a/drivers/media/usb/cx231xx/cx231xx.h
+++ b/drivers/media/usb/cx231xx/cx231xx.h
@@ -625,6 +625,7 @@ struct cx231xx {
/* I2C adapters: Master 1 & 2 (External) & Master 3 (Internal only) */
struct cx231xx_i2c i2c_bus[3];
+ struct i2c_mux_core *muxc;
struct i2c_adapter *i2c_mux_adap[2];
unsigned int xc_fw_load_done:1;
@@ -759,6 +760,7 @@ int cx231xx_reset_analog_tuner(struct cx231xx *dev);
void cx231xx_do_i2c_scan(struct cx231xx *dev, int i2c_port);
int cx231xx_i2c_register(struct cx231xx_i2c *bus);
int cx231xx_i2c_unregister(struct cx231xx_i2c *bus);
+int cx231xx_i2c_mux_create(struct cx231xx *dev);
int cx231xx_i2c_mux_register(struct cx231xx *dev, int mux_no);
void cx231xx_i2c_mux_unregister(struct cx231xx *dev, int mux_no);
struct i2c_adapter *cx231xx_get_i2c_adap(struct cx231xx *dev, int i2c_port);
diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
index e16ea5717b7f..6bfc2f9a5a24 100644
--- a/drivers/of/unittest.c
+++ b/drivers/of/unittest.c
@@ -1695,6 +1695,7 @@ static int unittest_i2c_mux_probe(struct i2c_client *client,
struct device *dev = &client->dev;
struct i2c_adapter *adap = to_i2c_adapter(dev->parent);
struct device_node *np = client->dev.of_node, *child;
+ struct i2c_mux_core *muxc;
struct unittest_i2c_mux_data *stm;
u32 reg, max_reg;
@@ -1720,14 +1721,14 @@ static int unittest_i2c_mux_probe(struct i2c_client *client,
}
size = offsetof(struct unittest_i2c_mux_data, adap[nchans]);
- stm = devm_kzalloc(dev, size, GFP_KERNEL);
- if (!stm) {
- dev_err(dev, "Out of memory\n");
+ muxc = i2c_mux_alloc(dev, size);
+ if (!muxc)
return -ENOMEM;
- }
+ muxc->parent = adap;
+ stm = i2c_mux_priv(muxc);
stm->nchans = nchans;
for (i = 0; i < nchans; i++) {
- stm->adap[i] = i2c_add_mux_adapter(adap, dev, client,
+ stm->adap[i] = i2c_add_mux_adapter(muxc, dev, client,
0, i, 0, unittest_i2c_mux_select_chan, NULL);
if (!stm->adap[i]) {
dev_err(dev, "Failed to register mux #%d\n", i);
@@ -1737,7 +1738,7 @@ static int unittest_i2c_mux_probe(struct i2c_client *client,
}
}
- i2c_set_clientdata(client, stm);
+ i2c_set_clientdata(client, muxc);
return 0;
};
@@ -1746,7 +1747,8 @@ static int unittest_i2c_mux_remove(struct i2c_client *client)
{
struct device *dev = &client->dev;
struct device_node *np = client->dev.of_node;
- struct unittest_i2c_mux_data *stm = i2c_get_clientdata(client);
+ struct i2c_mux_core *muxc = i2c_get_clientdata(client);
+ struct unittest_i2c_mux_data *stm = i2c_mux_priv(muxc);
int i;
dev_dbg(dev, "%s for node @%s\n", __func__, np->full_name);
diff --git a/include/linux/i2c-mux.h b/include/linux/i2c-mux.h
index b5f9a007a3ab..3ca1783b86ac 100644
--- a/include/linux/i2c-mux.h
+++ b/include/linux/i2c-mux.h
@@ -27,13 +27,25 @@
#ifdef __KERNEL__
+struct i2c_mux_core {
+ struct i2c_adapter *parent;
+ void *priv;
+};
+
+struct i2c_mux_core *i2c_mux_alloc(struct device *dev, int sizeof_priv);
+
+static inline void *i2c_mux_priv(struct i2c_mux_core *muxc)
+{
+ return muxc->priv;
+}
+
/*
* Called to create a i2c bus on a multiplexed bus segment.
* The mux_dev and chan_id parameters are passed to the select
* and deselect callback functions to perform hardware-specific
* mux control.
*/
-struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
+struct i2c_adapter *i2c_add_mux_adapter(struct i2c_mux_core *muxc,
struct device *mux_dev,
void *mux_priv, u32 force_nr, u32 chan_id,
unsigned int class,
--
2.1.4
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v3 2/8] i2c-mux: move select and deselect ops to i2c_mux_core
2016-01-08 15:04 [PATCH v3 0/8] i2c mux cleanup and locking update Peter Rosin
[not found] ` <1452265496-22475-1-git-send-email-peda-SamgB31n2u5IcsJQ0EH25Q@public.gmane.org>
@ 2016-01-08 15:04 ` Peter Rosin
2016-01-08 15:04 ` [PATCH v3 3/8] i2c-mux: move the slave side adapter management " Peter Rosin
` (6 subsequent siblings)
8 siblings, 0 replies; 15+ messages in thread
From: Peter Rosin @ 2016-01-08 15:04 UTC (permalink / raw)
To: Wolfram Sang
Cc: Peter Rosin, Peter Korsgaard, Guenter Roeck, Jonathan Cameron,
Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald,
Antti Palosaari, Mauro Carvalho Chehab, Rob Herring, Frank Rowand,
Grant Likely, Srinivas Pandruvada, Adriana Reus,
Krzysztof Kozlowski, Hans Verkuil, Nicholas Mc Guire,
Olli Salonen, Peter Rosin, linux-i2c, linux-kernel, linux-iio,
linux-media, devicetree
From: Peter Rosin <peda@axentia.se>
The mux select and deselect ops are common to the mux most of the time,
so store the ops in the mux core.
Change the select and deselect op to work in terms of the mux core instead
of the child adapter. No driver uses the child adapter anyway, and if it
is needed in a future mux driver it can be worked out from the channel id.
i2c-arb-gpio-challenge is special in that it needs the mux device pointer
in the select op, so store that device pointer in the mux core as well.
This pointer is going to get further use in later commits.
i2c-mux-pca954x is special since it does not add its deselect op to all
its child adapters, handle this by adding a mask that makes the deselect
op a no-operation for child adapters not wishing to deselect the mux.
Signed-off-by: Peter Rosin <peda@axentia.se>
---
drivers/i2c/i2c-mux.c | 31 ++++++++++-------------------
drivers/i2c/muxes/i2c-arb-gpio-challenge.c | 18 ++++++++---------
drivers/i2c/muxes/i2c-mux-gpio.c | 19 +++++++++---------
drivers/i2c/muxes/i2c-mux-pca9541.c | 20 +++++++++++--------
drivers/i2c/muxes/i2c-mux-pca954x.c | 32 +++++++++++++++++++-----------
drivers/i2c/muxes/i2c-mux-pinctrl.c | 20 ++++++++-----------
drivers/i2c/muxes/i2c-mux-reg.c | 21 +++++++++-----------
drivers/iio/imu/inv_mpu6050/inv_mpu_core.c | 17 +++++++---------
drivers/media/dvb-frontends/m88ds3103.c | 8 ++++----
drivers/media/dvb-frontends/rtl2830.c | 8 ++++----
drivers/media/dvb-frontends/rtl2832.c | 15 +++++++-------
drivers/media/dvb-frontends/si2168.c | 13 ++++++------
drivers/media/usb/cx231xx/cx231xx-i2c.c | 12 ++++-------
drivers/of/unittest.c | 7 +++----
include/linux/i2c-mux.h | 15 +++++++-------
15 files changed, 122 insertions(+), 134 deletions(-)
diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c
index c2163f6b51d5..6c5cb9f7649b 100644
--- a/drivers/i2c/i2c-mux.c
+++ b/drivers/i2c/i2c-mux.c
@@ -32,13 +32,8 @@ struct i2c_mux_priv {
struct i2c_adapter adap;
struct i2c_algorithm algo;
struct i2c_mux_core *muxc;
-
struct device *mux_dev;
- void *mux_priv;
u32 chan_id;
-
- int (*select)(struct i2c_adapter *, void *mux_priv, u32 chan_id);
- int (*deselect)(struct i2c_adapter *, void *mux_priv, u32 chan_id);
};
static int i2c_mux_master_xfer(struct i2c_adapter *adap,
@@ -51,11 +46,11 @@ static int i2c_mux_master_xfer(struct i2c_adapter *adap,
/* Switch to the right mux port and perform the transfer. */
- ret = priv->select(parent, priv->mux_priv, priv->chan_id);
+ ret = muxc->select(muxc, priv->chan_id);
if (ret >= 0)
ret = __i2c_transfer(parent, msgs, num);
- if (priv->deselect)
- priv->deselect(parent, priv->mux_priv, priv->chan_id);
+ if (muxc->deselect)
+ muxc->deselect(muxc, priv->chan_id);
return ret;
}
@@ -72,12 +67,12 @@ static int i2c_mux_smbus_xfer(struct i2c_adapter *adap,
/* Select the right mux port and perform the transfer. */
- ret = priv->select(parent, priv->mux_priv, priv->chan_id);
+ ret = muxc->select(muxc, priv->chan_id);
if (ret >= 0)
ret = parent->algo->smbus_xfer(parent, addr, flags,
read_write, command, size, data);
- if (priv->deselect)
- priv->deselect(parent, priv->mux_priv, priv->chan_id);
+ if (muxc->deselect)
+ muxc->deselect(muxc, priv->chan_id);
return ret;
}
@@ -113,18 +108,15 @@ struct i2c_mux_core *i2c_mux_alloc(struct device *dev, int sizeof_priv)
return NULL;
if (sizeof_priv)
muxc->priv = muxc + 1;
+ muxc->dev = dev;
return muxc;
}
EXPORT_SYMBOL_GPL(i2c_mux_alloc);
struct i2c_adapter *i2c_add_mux_adapter(struct i2c_mux_core *muxc,
- struct device *mux_dev,
- void *mux_priv, u32 force_nr, u32 chan_id,
- unsigned int class,
- int (*select) (struct i2c_adapter *,
- void *, u32),
- int (*deselect) (struct i2c_adapter *,
- void *, u32))
+ struct device *mux_dev,
+ u32 force_nr, u32 chan_id,
+ unsigned int class)
{
struct i2c_adapter *parent = muxc->parent;
struct i2c_mux_priv *priv;
@@ -138,10 +130,7 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_mux_core *muxc,
/* Set up private adapter data */
priv->muxc = muxc;
priv->mux_dev = mux_dev;
- priv->mux_priv = mux_priv;
priv->chan_id = chan_id;
- priv->select = select;
- priv->deselect = deselect;
/* Need to do algo dynamically because we don't know ahead
* of time what sort of physical adapter we'll be dealing with.
diff --git a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
index 6e27ea4fb25a..1e1a479d5b61 100644
--- a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
+++ b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
@@ -58,9 +58,9 @@ struct i2c_arbitrator_data {
*
* Use the GPIO-based signalling protocol; return -EBUSY if we fail.
*/
-static int i2c_arbitrator_select(struct i2c_adapter *adap, void *data, u32 chan)
+static int i2c_arbitrator_select(struct i2c_mux_core *muxc, u32 chan)
{
- const struct i2c_arbitrator_data *arb = data;
+ const struct i2c_arbitrator_data *arb = i2c_mux_priv(muxc);
unsigned long stop_retry, stop_time;
/* Start a round of trying to claim the bus */
@@ -92,7 +92,7 @@ static int i2c_arbitrator_select(struct i2c_adapter *adap, void *data, u32 chan)
/* Give up, release our claim */
gpio_set_value(arb->our_gpio, arb->our_gpio_release);
udelay(arb->slew_delay_us);
- dev_err(&adap->dev, "Could not claim bus, timeout\n");
+ dev_err(muxc->dev, "Could not claim bus, timeout\n");
return -EBUSY;
}
@@ -101,10 +101,9 @@ static int i2c_arbitrator_select(struct i2c_adapter *adap, void *data, u32 chan)
*
* Release the I2C bus using the GPIO-based signalling protocol.
*/
-static int i2c_arbitrator_deselect(struct i2c_adapter *adap, void *data,
- u32 chan)
+static int i2c_arbitrator_deselect(struct i2c_mux_core *muxc, u32 chan)
{
- const struct i2c_arbitrator_data *arb = data;
+ const struct i2c_arbitrator_data *arb = i2c_mux_priv(muxc);
/* Release the bus and wait for the other master to notice */
gpio_set_value(arb->our_gpio, arb->our_gpio_release);
@@ -140,6 +139,9 @@ static int i2c_arbitrator_probe(struct platform_device *pdev)
arb = i2c_mux_priv(muxc);
platform_set_drvdata(pdev, muxc);
+
+ muxc->select = i2c_arbitrator_select,
+ muxc->deselect = i2c_arbitrator_deselect;
/* Request GPIOs */
ret = of_get_named_gpio_flags(np, "our-claim-gpio", 0, &gpio_flags);
if (!gpio_is_valid(ret)) {
@@ -203,9 +205,7 @@ static int i2c_arbitrator_probe(struct platform_device *pdev)
}
/* Actually add the mux adapter */
- arb->child = i2c_add_mux_adapter(muxc, dev, arb, 0, 0, 0,
- i2c_arbitrator_select,
- i2c_arbitrator_deselect);
+ arb->child = i2c_add_mux_adapter(muxc, dev, 0, 0, 0);
if (!arb->child) {
dev_err(dev, "Failed to add adapter\n");
ret = -ENODEV;
diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
index ee43dd76a4d7..d89a0fbca4bc 100644
--- a/drivers/i2c/muxes/i2c-mux-gpio.c
+++ b/drivers/i2c/muxes/i2c-mux-gpio.c
@@ -32,18 +32,18 @@ static void i2c_mux_gpio_set(const struct gpiomux *mux, unsigned val)
val & (1 << i));
}
-static int i2c_mux_gpio_select(struct i2c_adapter *adap, void *data, u32 chan)
+static int i2c_mux_gpio_select(struct i2c_mux_core *muxc, u32 chan)
{
- struct gpiomux *mux = data;
+ struct gpiomux *mux = i2c_mux_priv(muxc);
i2c_mux_gpio_set(mux, chan);
return 0;
}
-static int i2c_mux_gpio_deselect(struct i2c_adapter *adap, void *data, u32 chan)
+static int i2c_mux_gpio_deselect(struct i2c_mux_core *muxc, u32 chan)
{
- struct gpiomux *mux = data;
+ struct gpiomux *mux = i2c_mux_priv(muxc);
i2c_mux_gpio_set(mux, mux->data.idle);
@@ -138,7 +138,6 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
struct i2c_mux_core *muxc;
struct gpiomux *mux;
struct i2c_adapter *parent;
- int (*deselect) (struct i2c_adapter *, void *, u32);
unsigned initial_state, gpio_base;
int i, ret;
@@ -180,6 +179,7 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
return -EPROBE_DEFER;
muxc->parent = parent;
+ muxc->select = i2c_mux_gpio_select;
mux->gpio_base = gpio_base;
mux->adap = devm_kzalloc(&pdev->dev,
@@ -193,10 +193,10 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
if (mux->data.idle != I2C_MUX_GPIO_NO_IDLE) {
initial_state = mux->data.idle;
- deselect = i2c_mux_gpio_deselect;
+ muxc->deselect = i2c_mux_gpio_deselect;
} else {
initial_state = mux->data.values[0];
- deselect = NULL;
+ muxc->deselect = NULL;
}
for (i = 0; i < mux->data.n_gpios; i++) {
@@ -222,9 +222,8 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
u32 nr = mux->data.base_nr ? (mux->data.base_nr + i) : 0;
unsigned int class = mux->data.classes ? mux->data.classes[i] : 0;
- mux->adap[i] = i2c_add_mux_adapter(muxc, &pdev->dev, mux, nr,
- mux->data.values[i], class,
- i2c_mux_gpio_select, deselect);
+ mux->adap[i] = i2c_add_mux_adapter(muxc, &pdev->dev, nr,
+ mux->data.values[i], class);
if (!mux->adap[i]) {
ret = -ENODEV;
dev_err(&pdev->dev, "Failed to add adapter %d\n", i);
diff --git a/drivers/i2c/muxes/i2c-mux-pca9541.c b/drivers/i2c/muxes/i2c-mux-pca9541.c
index 78648d1263bc..ae42039459d0 100644
--- a/drivers/i2c/muxes/i2c-mux-pca9541.c
+++ b/drivers/i2c/muxes/i2c-mux-pca9541.c
@@ -73,6 +73,7 @@
#define SELECT_DELAY_LONG 1000
struct pca9541 {
+ struct i2c_client *client;
struct i2c_adapter *mux_adap;
unsigned long select_timeout;
unsigned long arb_timeout;
@@ -286,9 +287,10 @@ static int pca9541_arbitrate(struct i2c_client *client)
return 0;
}
-static int pca9541_select_chan(struct i2c_adapter *adap, void *client, u32 chan)
+static int pca9541_select_chan(struct i2c_mux_core *muxc, u32 chan)
{
- struct pca9541 *data = i2c_get_clientdata(client);
+ struct pca9541 *data = i2c_mux_priv(muxc);
+ struct i2c_client *client = data->client;
int ret;
unsigned long timeout = jiffies + ARB2_TIMEOUT;
/* give up after this time */
@@ -310,9 +312,11 @@ static int pca9541_select_chan(struct i2c_adapter *adap, void *client, u32 chan)
return -ETIMEDOUT;
}
-static int pca9541_release_chan(struct i2c_adapter *adap,
- void *client, u32 chan)
+static int pca9541_release_chan(struct i2c_mux_core *muxc, u32 chan)
{
+ struct pca9541 *data = i2c_mux_priv(muxc);
+ struct i2c_client *client = data->client;
+
pca9541_release_bus(client);
return 0;
}
@@ -339,7 +343,10 @@ static int pca9541_probe(struct i2c_client *client,
i2c_set_clientdata(client, muxc);
+ data->client = client;
muxc->parent = adap;
+ muxc->select = pca9541_select_chan;
+ muxc->deselect = pca9541_release_chan;
/*
* I2C accesses are unprotected here.
@@ -354,10 +361,7 @@ static int pca9541_probe(struct i2c_client *client,
force = 0;
if (pdata)
force = pdata->modes[0].adap_id;
- data->mux_adap = i2c_add_mux_adapter(muxc, &client->dev, client,
- force, 0, 0,
- pca9541_select_chan,
- pca9541_release_chan);
+ data->mux_adap = i2c_add_mux_adapter(muxc, &client->dev, force, 0, 0);
if (data->mux_adap == NULL) {
dev_err(&client->dev, "failed to register master selector\n");
diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
index acc2f87fe321..9e9d708fb2cb 100644
--- a/drivers/i2c/muxes/i2c-mux-pca954x.c
+++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
@@ -63,6 +63,8 @@ struct pca954x {
struct i2c_adapter *virt_adaps[PCA954X_MAX_NCHANS];
u8 last_chan; /* last register value */
+ u8 deselect;
+ struct i2c_client *client;
};
struct chip_desc {
@@ -146,10 +148,10 @@ static int pca954x_reg_write(struct i2c_adapter *adap,
return ret;
}
-static int pca954x_select_chan(struct i2c_adapter *adap,
- void *client, u32 chan)
+static int pca954x_select_chan(struct i2c_mux_core *muxc, u32 chan)
{
- struct pca954x *data = i2c_get_clientdata(client);
+ struct pca954x *data = i2c_mux_priv(muxc);
+ struct i2c_client *client = data->client;
const struct chip_desc *chip = &chips[data->type];
u8 regval;
int ret = 0;
@@ -162,21 +164,24 @@ static int pca954x_select_chan(struct i2c_adapter *adap,
/* Only select the channel if its different from the last channel */
if (data->last_chan != regval) {
- ret = pca954x_reg_write(adap, client, regval);
+ ret = pca954x_reg_write(muxc->parent, client, regval);
data->last_chan = regval;
}
return ret;
}
-static int pca954x_deselect_mux(struct i2c_adapter *adap,
- void *client, u32 chan)
+static int pca954x_deselect_mux(struct i2c_mux_core *muxc, u32 chan)
{
- struct pca954x *data = i2c_get_clientdata(client);
+ struct pca954x *data = i2c_mux_priv(muxc);
+ struct i2c_client *client = data->client;
+
+ if (!(data->deselect & (1 << chan)))
+ return 0;
/* Deselect active channel */
data->last_chan = 0;
- return pca954x_reg_write(adap, client, data->last_chan);
+ return pca954x_reg_write(muxc->parent, client, data->last_chan);
}
/*
@@ -204,6 +209,7 @@ static int pca954x_probe(struct i2c_client *client,
data = i2c_mux_priv(muxc);
i2c_set_clientdata(client, muxc);
+ data->client = client;
/* Get the mux out of reset if a reset GPIO is specified. */
gpio = devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_LOW);
@@ -220,6 +226,8 @@ static int pca954x_probe(struct i2c_client *client,
}
muxc->parent = adap;
+ muxc->select = pca954x_select_chan;
+ muxc->deselect = pca954x_deselect_mux;
data->type = id->driver_data;
data->last_chan = 0; /* force the first selection */
@@ -241,13 +249,13 @@ static int pca954x_probe(struct i2c_client *client,
/* discard unconfigured channels */
break;
idle_disconnect_pd = pdata->modes[num].deselect_on_exit;
+ data->deselect |= (idle_disconnect_pd
+ || idle_disconnect_dt) << num;
}
data->virt_adaps[num] =
- i2c_add_mux_adapter(muxc, &client->dev, client,
- force, num, class, pca954x_select_chan,
- (idle_disconnect_pd || idle_disconnect_dt)
- ? pca954x_deselect_mux : NULL);
+ i2c_add_mux_adapter(muxc, &client->dev,
+ force, num, class);
if (data->virt_adaps[num] == NULL) {
ret = -ENODEV;
diff --git a/drivers/i2c/muxes/i2c-mux-pinctrl.c b/drivers/i2c/muxes/i2c-mux-pinctrl.c
index 810f75f114a7..e87c8f77037a 100644
--- a/drivers/i2c/muxes/i2c-mux-pinctrl.c
+++ b/drivers/i2c/muxes/i2c-mux-pinctrl.c
@@ -34,18 +34,16 @@ struct i2c_mux_pinctrl {
struct i2c_adapter **busses;
};
-static int i2c_mux_pinctrl_select(struct i2c_adapter *adap, void *data,
- u32 chan)
+static int i2c_mux_pinctrl_select(struct i2c_mux_core *muxc, u32 chan)
{
- struct i2c_mux_pinctrl *mux = data;
+ struct i2c_mux_pinctrl *mux = i2c_mux_priv(muxc);
return pinctrl_select_state(mux->pinctrl, mux->states[chan]);
}
-static int i2c_mux_pinctrl_deselect(struct i2c_adapter *adap, void *data,
- u32 chan)
+static int i2c_mux_pinctrl_deselect(struct i2c_mux_core *muxc, u32 chan)
{
- struct i2c_mux_pinctrl *mux = data;
+ struct i2c_mux_pinctrl *mux = i2c_mux_priv(muxc);
return pinctrl_select_state(mux->pinctrl, mux->state_idle);
}
@@ -132,7 +130,6 @@ static int i2c_mux_pinctrl_probe(struct platform_device *pdev)
{
struct i2c_mux_core *muxc;
struct i2c_mux_pinctrl *mux;
- int (*deselect)(struct i2c_adapter *, void *, u32);
int i, ret;
muxc = i2c_mux_alloc(&pdev->dev, sizeof(*mux));
@@ -203,10 +200,11 @@ static int i2c_mux_pinctrl_probe(struct platform_device *pdev)
goto err;
}
- deselect = i2c_mux_pinctrl_deselect;
+ muxc->deselect = i2c_mux_pinctrl_deselect;
} else {
- deselect = NULL;
+ muxc->deselect = NULL;
}
+ muxc->select = i2c_mux_pinctrl_select;
muxc->parent = i2c_get_adapter(mux->pdata->parent_bus_num);
if (!muxc->parent) {
@@ -221,9 +219,7 @@ static int i2c_mux_pinctrl_probe(struct platform_device *pdev)
(mux->pdata->base_bus_num + i) : 0;
mux->busses[i] = i2c_add_mux_adapter(muxc, &pdev->dev,
- mux, bus, i, 0,
- i2c_mux_pinctrl_select,
- deselect);
+ bus, i, 0);
if (!mux->busses[i]) {
ret = -ENODEV;
dev_err(&pdev->dev, "Failed to add adapter %d\n", i);
diff --git a/drivers/i2c/muxes/i2c-mux-reg.c b/drivers/i2c/muxes/i2c-mux-reg.c
index 8bde4cfac512..3b01e7809a66 100644
--- a/drivers/i2c/muxes/i2c-mux-reg.c
+++ b/drivers/i2c/muxes/i2c-mux-reg.c
@@ -63,18 +63,16 @@ static int i2c_mux_reg_set(const struct regmux *mux, unsigned int chan_id)
return 0;
}
-static int i2c_mux_reg_select(struct i2c_adapter *adap, void *data,
- unsigned int chan)
+static int i2c_mux_reg_select(struct i2c_mux_core *muxc, u32 chan)
{
- struct regmux *mux = data;
+ struct regmux *mux = i2c_mux_priv(muxc);
return i2c_mux_reg_set(mux, chan);
}
-static int i2c_mux_reg_deselect(struct i2c_adapter *adap, void *data,
- unsigned int chan)
+static int i2c_mux_reg_deselect(struct i2c_mux_core *muxc, u32 chan)
{
- struct regmux *mux = data;
+ struct regmux *mux = i2c_mux_priv(muxc);
if (mux->data.idle_in_use)
return i2c_mux_reg_set(mux, mux->data.idle);
@@ -173,7 +171,6 @@ static int i2c_mux_reg_probe(struct platform_device *pdev)
struct regmux *mux;
struct i2c_adapter *parent;
struct resource *res;
- int (*deselect)(struct i2c_adapter *, void *, u32);
unsigned int class;
int i, ret, nr;
@@ -225,19 +222,19 @@ static int i2c_mux_reg_probe(struct platform_device *pdev)
return -ENOMEM;
}
+ muxc->select = i2c_mux_reg_select;
if (mux->data.idle_in_use)
- deselect = i2c_mux_reg_deselect;
+ muxc->deselect = i2c_mux_reg_deselect;
else
- deselect = NULL;
+ muxc->deselect = NULL;
for (i = 0; i < mux->data.n_values; i++) {
nr = mux->data.base_nr ? (mux->data.base_nr + i) : 0;
class = mux->data.classes ? mux->data.classes[i] : 0;
- mux->adap[i] = i2c_add_mux_adapter(muxc, &pdev->dev, mux,
+ mux->adap[i] = i2c_add_mux_adapter(muxc, &pdev->dev,
nr, mux->data.values[i],
- class, i2c_mux_reg_select,
- deselect);
+ class);
if (!mux->adap[i]) {
ret = -ENODEV;
dev_err(&pdev->dev, "Failed to add adapter %d\n", i);
diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
index 3aab0d7a1bdc..0a47396bc5be 100644
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
@@ -109,10 +109,9 @@ static int inv_mpu6050_write_reg_unlocked(struct inv_mpu6050_state *st,
return 0;
}
-static int inv_mpu6050_select_bypass(struct i2c_adapter *adap, void *mux_priv,
- u32 chan_id)
+static int inv_mpu6050_select_bypass(struct i2c_mux_core *muxc, u32 chan_id)
{
- struct iio_dev *indio_dev = mux_priv;
+ struct iio_dev *indio_dev = i2c_mux_priv(muxc);
struct inv_mpu6050_state *st = iio_priv(indio_dev);
int ret = 0;
@@ -138,10 +137,9 @@ write_error:
return ret;
}
-static int inv_mpu6050_deselect_bypass(struct i2c_adapter *adap,
- void *mux_priv, u32 chan_id)
+static int inv_mpu6050_deselect_bypass(struct i2c_mux_core *muxc, u32 chan_id)
{
- struct iio_dev *indio_dev = mux_priv;
+ struct iio_dev *indio_dev = i2c_mux_priv(muxc);
struct inv_mpu6050_state *st = iio_priv(indio_dev);
mutex_lock(&indio_dev->mlock);
@@ -849,13 +847,12 @@ static int inv_mpu_probe(struct i2c_client *client,
}
st->muxc->priv = indio_dev;
st->muxc->parent = client->adapter;
+ st->muxc->select = inv_mpu6050_select_bypass;
+ st->muxc->deselect = inv_mpu6050_deselect_bypass;
st->mux_adapter = i2c_add_mux_adapter(st->muxc,
&client->dev,
- indio_dev,
- 0, 0, 0,
- inv_mpu6050_select_bypass,
- inv_mpu6050_deselect_bypass);
+ 0, 0, 0);
if (!st->mux_adapter) {
result = -ENODEV;
goto out_unreg_device;
diff --git a/drivers/media/dvb-frontends/m88ds3103.c b/drivers/media/dvb-frontends/m88ds3103.c
index a0006aec6937..c9f8296ea421 100644
--- a/drivers/media/dvb-frontends/m88ds3103.c
+++ b/drivers/media/dvb-frontends/m88ds3103.c
@@ -1251,9 +1251,9 @@ static void m88ds3103_release(struct dvb_frontend *fe)
i2c_unregister_device(client);
}
-static int m88ds3103_select(struct i2c_adapter *adap, void *mux_priv, u32 chan)
+static int m88ds3103_select(struct i2c_mux_core *muxc, u32 chan)
{
- struct m88ds3103_dev *dev = mux_priv;
+ struct m88ds3103_dev *dev = i2c_mux_priv(muxc);
struct i2c_client *client = dev->client;
int ret;
struct i2c_msg msg = {
@@ -1473,11 +1473,11 @@ static int m88ds3103_probe(struct i2c_client *client,
}
dev->muxc->priv = dev;
dev->muxc->parent = client->adapter;
+ dev->muxc->select = m88ds3103_select;
/* create mux i2c adapter for tuner */
dev->i2c_adapter = i2c_add_mux_adapter(dev->muxc, &client->dev,
- dev, 0, 0, 0, m88ds3103_select,
- NULL);
+ 0, 0, 0);
if (dev->i2c_adapter == NULL) {
ret = -ENOMEM;
goto err_kfree;
diff --git a/drivers/media/dvb-frontends/rtl2830.c b/drivers/media/dvb-frontends/rtl2830.c
index ebf28b49cab2..d6330e8d5fa4 100644
--- a/drivers/media/dvb-frontends/rtl2830.c
+++ b/drivers/media/dvb-frontends/rtl2830.c
@@ -677,9 +677,9 @@ err:
* adapter lock is already taken by tuner driver.
* Gate is closed automatically after single I2C transfer.
*/
-static int rtl2830_select(struct i2c_adapter *adap, void *mux_priv, u32 chan_id)
+static int rtl2830_select(struct i2c_mux_core *muxc, u32 chan_id)
{
- struct i2c_client *client = mux_priv;
+ struct i2c_client *client = i2c_mux_priv(muxc);
struct rtl2830_dev *dev = i2c_get_clientdata(client);
int ret;
@@ -871,10 +871,10 @@ static int rtl2830_probe(struct i2c_client *client,
}
dev->muxc->priv = client;
dev->muxc->parent = client->adapter;
+ dev->muxc->select = rtl2830_select;
/* create muxed i2c adapter for tuner */
- dev->adapter = i2c_add_mux_adapter(dev->muxc, &client->dev,
- client, 0, 0, 0, rtl2830_select, NULL);
+ dev->adapter = i2c_add_mux_adapter(dev->muxc, &client->dev, 0, 0, 0);
if (dev->adapter == NULL) {
ret = -ENODEV;
goto err_regmap_exit;
diff --git a/drivers/media/dvb-frontends/rtl2832.c b/drivers/media/dvb-frontends/rtl2832.c
index 38402ad3ecdd..c8fd990fdae8 100644
--- a/drivers/media/dvb-frontends/rtl2832.c
+++ b/drivers/media/dvb-frontends/rtl2832.c
@@ -866,9 +866,9 @@ err:
dev_dbg(&client->dev, "failed=%d\n", ret);
}
-static int rtl2832_select(struct i2c_adapter *adap, void *mux_priv, u32 chan_id)
+static int rtl2832_select(struct i2c_mux_core *muxc, u32 chan_id)
{
- struct rtl2832_dev *dev = mux_priv;
+ struct rtl2832_dev *dev = i2c_mux_priv(muxc);
struct i2c_client *client = dev->client;
int ret;
@@ -889,10 +889,9 @@ err:
return ret;
}
-static int rtl2832_deselect(struct i2c_adapter *adap, void *mux_priv,
- u32 chan_id)
+static int rtl2832_deselect(struct i2c_mux_core *muxc, u32 chan_id)
{
- struct rtl2832_dev *dev = mux_priv;
+ struct rtl2832_dev *dev = i2c_mux_priv(muxc);
schedule_delayed_work(&dev->i2c_gate_work, usecs_to_jiffies(100));
return 0;
@@ -1268,10 +1267,12 @@ static int rtl2832_probe(struct i2c_client *client,
}
dev->muxc->priv = dev;
dev->muxc->parent = i2c;
+ dev->muxc->select = rtl2832_select;
+ dev->muxc->deselect = rtl2832_deselect;
/* create muxed i2c adapter for demod tuner bus */
- dev->i2c_adapter_tuner = i2c_add_mux_adapter(dev->muxc, &i2c->dev, dev,
- 0, 0, 0, rtl2832_select, rtl2832_deselect);
+ dev->i2c_adapter_tuner = i2c_add_mux_adapter(dev->muxc, &i2c->dev,
+ 0, 0, 0);
if (dev->i2c_adapter_tuner == NULL) {
ret = -ENODEV;
goto err_regmap_exit;
diff --git a/drivers/media/dvb-frontends/si2168.c b/drivers/media/dvb-frontends/si2168.c
index a52756bf9834..5b1872b1bbf4 100644
--- a/drivers/media/dvb-frontends/si2168.c
+++ b/drivers/media/dvb-frontends/si2168.c
@@ -615,9 +615,9 @@ static int si2168_get_tune_settings(struct dvb_frontend *fe,
* We must use unlocked I2C I/O because I2C adapter lock is already taken
* by the caller (usually tuner driver).
*/
-static int si2168_select(struct i2c_adapter *adap, void *mux_priv, u32 chan)
+static int si2168_select(struct i2c_mux_core *muxc, u32 chan)
{
- struct i2c_client *client = mux_priv;
+ struct i2c_client *client = i2c_mux_priv(muxc);
int ret;
struct si2168_cmd cmd;
@@ -635,9 +635,9 @@ err:
return ret;
}
-static int si2168_deselect(struct i2c_adapter *adap, void *mux_priv, u32 chan)
+static int si2168_deselect(struct i2c_mux_core *muxc, u32 chan)
{
- struct i2c_client *client = mux_priv;
+ struct i2c_client *client = i2c_mux_priv(muxc);
int ret;
struct si2168_cmd cmd;
@@ -715,10 +715,11 @@ static int si2168_probe(struct i2c_client *client,
}
dev->muxc->priv = client;
dev->muxc->parent = client->adapter;
+ dev->muxc->select = si2168_select;
+ dev->muxc->deselect = si2168_deselect;
/* create mux i2c adapter for tuner */
- dev->adapter = i2c_add_mux_adapter(dev->muxc, &client->dev,
- client, 0, 0, 0, si2168_select, si2168_deselect);
+ dev->adapter = i2c_add_mux_adapter(dev->muxc, &client->dev, 0, 0, 0);
if (dev->adapter == NULL) {
ret = -ENODEV;
goto err_kfree;
diff --git a/drivers/media/usb/cx231xx/cx231xx-i2c.c b/drivers/media/usb/cx231xx/cx231xx-i2c.c
index 09c30e753ca5..51760bfc7cbc 100644
--- a/drivers/media/usb/cx231xx/cx231xx-i2c.c
+++ b/drivers/media/usb/cx231xx/cx231xx-i2c.c
@@ -557,10 +557,9 @@ int cx231xx_i2c_unregister(struct cx231xx_i2c *bus)
* cx231xx_i2c_mux_select()
* switch i2c master number 1 between port1 and port3
*/
-static int cx231xx_i2c_mux_select(struct i2c_adapter *adap,
- void *mux_priv, u32 chan_id)
+static int cx231xx_i2c_mux_select(struct i2c_mux_core *muxc, u32 chan_id)
{
- struct cx231xx *dev = mux_priv;
+ struct cx231xx *dev = i2c_mux_priv(muxc);
return cx231xx_enable_i2c_port_3(dev, chan_id);
}
@@ -572,6 +571,7 @@ int cx231xx_i2c_mux_create(struct cx231xx *dev)
return -ENOMEM;
dev->muxc->priv = dev;
dev->muxc->parent = &dev->i2c_bus[1].i2c_adap;
+ dev->muxc->select = cx231xx_i2c_mux_select;
return 0;
}
@@ -582,13 +582,9 @@ int cx231xx_i2c_mux_register(struct cx231xx *dev, int mux_no)
dev->i2c_mux_adap[mux_no] = i2c_add_mux_adapter(dev->muxc,
mux_dev,
- dev /* mux_priv */,
0,
mux_no /* chan_id */,
- 0 /* class */,
- &cx231xx_i2c_mux_select,
- NULL);
-
+ 0 /* class */);
if (!dev->i2c_mux_adap[mux_no])
dev_warn(dev->dev,
"i2c mux %d register FAILED\n", mux_no);
diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
index 6bfc2f9a5a24..a4abd9b588b9 100644
--- a/drivers/of/unittest.c
+++ b/drivers/of/unittest.c
@@ -1682,8 +1682,7 @@ struct unittest_i2c_mux_data {
struct i2c_adapter *adap[];
};
-static int unittest_i2c_mux_select_chan(struct i2c_adapter *adap,
- void *client, u32 chan)
+static int unittest_i2c_mux_select_chan(struct i2c_mux_core *muxc, u32 chan)
{
return 0;
}
@@ -1725,11 +1724,11 @@ static int unittest_i2c_mux_probe(struct i2c_client *client,
if (!muxc)
return -ENOMEM;
muxc->parent = adap;
+ muxc->select = unittest_i2c_mux_select_chan;
stm = i2c_mux_priv(muxc);
stm->nchans = nchans;
for (i = 0; i < nchans; i++) {
- stm->adap[i] = i2c_add_mux_adapter(muxc, dev, client,
- 0, i, 0, unittest_i2c_mux_select_chan, NULL);
+ stm->adap[i] = i2c_add_mux_adapter(muxc, dev, 0, i, 0);
if (!stm->adap[i]) {
dev_err(dev, "Failed to register mux #%d\n", i);
for (i--; i >= 0; i--)
diff --git a/include/linux/i2c-mux.h b/include/linux/i2c-mux.h
index 3ca1783b86ac..5cd6e1e664e0 100644
--- a/include/linux/i2c-mux.h
+++ b/include/linux/i2c-mux.h
@@ -29,7 +29,12 @@
struct i2c_mux_core {
struct i2c_adapter *parent;
+ struct device *dev;
+
void *priv;
+
+ int (*select)(struct i2c_mux_core *, u32 chan_id);
+ int (*deselect)(struct i2c_mux_core *, u32 chan_id);
};
struct i2c_mux_core *i2c_mux_alloc(struct device *dev, int sizeof_priv);
@@ -46,13 +51,9 @@ static inline void *i2c_mux_priv(struct i2c_mux_core *muxc)
* mux control.
*/
struct i2c_adapter *i2c_add_mux_adapter(struct i2c_mux_core *muxc,
- struct device *mux_dev,
- void *mux_priv, u32 force_nr, u32 chan_id,
- unsigned int class,
- int (*select) (struct i2c_adapter *,
- void *mux_dev, u32 chan_id),
- int (*deselect) (struct i2c_adapter *,
- void *mux_dev, u32 chan_id));
+ struct device *mux_dev,
+ u32 force_nr, u32 chan_id,
+ unsigned int class);
void i2c_del_mux_adapter(struct i2c_adapter *adap);
--
2.1.4
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v3 3/8] i2c-mux: move the slave side adapter management to i2c_mux_core
2016-01-08 15:04 [PATCH v3 0/8] i2c mux cleanup and locking update Peter Rosin
[not found] ` <1452265496-22475-1-git-send-email-peda-SamgB31n2u5IcsJQ0EH25Q@public.gmane.org>
2016-01-08 15:04 ` [PATCH v3 2/8] i2c-mux: move select and deselect ops to i2c_mux_core Peter Rosin
@ 2016-01-08 15:04 ` Peter Rosin
2016-01-08 15:04 ` [PATCH v3 4/8] i2c-mux: remove the mux dev pointer from the mux per channel data Peter Rosin
` (5 subsequent siblings)
8 siblings, 0 replies; 15+ messages in thread
From: Peter Rosin @ 2016-01-08 15:04 UTC (permalink / raw)
To: Wolfram Sang
Cc: Peter Rosin, Peter Korsgaard, Guenter Roeck, Jonathan Cameron,
Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald,
Antti Palosaari, Mauro Carvalho Chehab, Rob Herring, Frank Rowand,
Grant Likely, Srinivas Pandruvada, Adriana Reus,
Krzysztof Kozlowski, Hans Verkuil, Nicholas Mc Guire,
Olli Salonen, Peter Rosin, linux-i2c, linux-kernel, linux-iio,
linux-media, devicetree
From: Peter Rosin <peda@axentia.se>
All muxes have slave side adapters, many have some arbitrary number of
them. Handle this in the mux core, so that drivers are simplified.
Add i2c_mux_reserve_adapters that can be used when it is known in advance
how many child adapters that is to be added. This avoids reallocating
memory.
Drop i2c_del_mux_adapter and replace it with i2c_del_mux_adapters, since
no mux driver is dynamically deleting individual child adapters anyway.
Signed-off-by: Peter Rosin <peda@axentia.se>
---
drivers/i2c/i2c-mux.c | 73 ++++++++++++++++++++++------
drivers/i2c/muxes/i2c-arb-gpio-challenge.c | 10 ++--
drivers/i2c/muxes/i2c-mux-gpio.c | 23 +++------
drivers/i2c/muxes/i2c-mux-pca9541.c | 13 ++---
drivers/i2c/muxes/i2c-mux-pca954x.c | 26 ++++------
drivers/i2c/muxes/i2c-mux-pinctrl.c | 27 +++-------
drivers/i2c/muxes/i2c-mux-reg.c | 28 +++--------
drivers/iio/imu/inv_mpu6050/inv_mpu_acpi.c | 2 +-
drivers/iio/imu/inv_mpu6050/inv_mpu_core.c | 13 ++---
drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h | 2 +-
drivers/media/dvb-frontends/m88ds3103.c | 11 ++---
drivers/media/dvb-frontends/m88ds3103_priv.h | 1 -
drivers/media/dvb-frontends/rtl2830.c | 10 ++--
drivers/media/dvb-frontends/rtl2830_priv.h | 1 -
drivers/media/dvb-frontends/rtl2832.c | 11 ++---
drivers/media/dvb-frontends/rtl2832_priv.h | 1 -
drivers/media/dvb-frontends/si2168.c | 10 ++--
drivers/media/dvb-frontends/si2168_priv.h | 1 -
drivers/media/usb/cx231xx/cx231xx-core.c | 3 +-
drivers/media/usb/cx231xx/cx231xx-i2c.c | 26 +++++-----
drivers/media/usb/cx231xx/cx231xx.h | 2 +-
drivers/of/unittest.c | 28 ++++-------
include/linux/i2c-mux.h | 15 ++++--
23 files changed, 153 insertions(+), 184 deletions(-)
diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c
index 6c5cb9f7649b..3c56625ce13c 100644
--- a/drivers/i2c/i2c-mux.c
+++ b/drivers/i2c/i2c-mux.c
@@ -99,6 +99,31 @@ static unsigned int i2c_mux_parent_classes(struct i2c_adapter *parent)
return class;
}
+int i2c_mux_reserve_adapters(struct i2c_mux_core *muxc, int adapters)
+{
+ struct i2c_adapter **adapter;
+
+ if (adapters <= muxc->max_adapters)
+ return 0;
+
+ adapter = devm_kmalloc_array(muxc->dev,
+ adapters, sizeof(*adapter),
+ GFP_KERNEL);
+ if (!adapter)
+ return -ENOMEM;
+
+ if (muxc->adapter) {
+ memcpy(adapter, muxc->adapter,
+ muxc->max_adapters * sizeof(*adapter));
+ devm_kfree(muxc->dev, muxc->adapter);
+ }
+
+ muxc->adapter = adapter;
+ muxc->max_adapters = adapters;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(i2c_mux_reserve_adapters);
+
struct i2c_mux_core *i2c_mux_alloc(struct device *dev, int sizeof_priv)
{
struct i2c_mux_core *muxc;
@@ -113,19 +138,29 @@ struct i2c_mux_core *i2c_mux_alloc(struct device *dev, int sizeof_priv)
}
EXPORT_SYMBOL_GPL(i2c_mux_alloc);
-struct i2c_adapter *i2c_add_mux_adapter(struct i2c_mux_core *muxc,
- struct device *mux_dev,
- u32 force_nr, u32 chan_id,
- unsigned int class)
+int i2c_add_mux_adapter(struct i2c_mux_core *muxc,
+ struct device *mux_dev,
+ u32 force_nr, u32 chan_id,
+ unsigned int class)
{
struct i2c_adapter *parent = muxc->parent;
struct i2c_mux_priv *priv;
char symlink_name[20];
int ret;
+ if (muxc->adapters >= muxc->max_adapters) {
+ int new_max = 2 * muxc->max_adapters;
+
+ if (!new_max)
+ new_max = 1;
+ ret = i2c_mux_reserve_adapters(muxc, new_max);
+ if (ret)
+ return ret;
+ }
+
priv = kzalloc(sizeof(struct i2c_mux_priv), GFP_KERNEL);
if (!priv)
- return NULL;
+ return -ENOMEM;
/* Set up private adapter data */
priv->muxc = muxc;
@@ -197,7 +232,7 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_mux_core *muxc,
"failed to add mux-adapter (error=%d)\n",
ret);
kfree(priv);
- return NULL;
+ return ret;
}
WARN(sysfs_create_link(&priv->adap.dev.kobj, &mux_dev->kobj, "mux_device"),
@@ -209,23 +244,31 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_mux_core *muxc,
dev_info(&parent->dev, "Added multiplexed i2c bus %d\n",
i2c_adapter_id(&priv->adap));
- return &priv->adap;
+ muxc->adapter[muxc->adapters++] = &priv->adap;
+ return 0;
}
EXPORT_SYMBOL_GPL(i2c_add_mux_adapter);
-void i2c_del_mux_adapter(struct i2c_adapter *adap)
+void i2c_del_mux_adapters(struct i2c_mux_core *muxc)
{
- struct i2c_mux_priv *priv = adap->algo_data;
char symlink_name[20];
- snprintf(symlink_name, sizeof(symlink_name), "channel-%u", priv->chan_id);
- sysfs_remove_link(&priv->mux_dev->kobj, symlink_name);
+ while (muxc->adapters) {
+ struct i2c_adapter *adap = muxc->adapter[--muxc->adapters];
+ struct i2c_mux_priv *priv = adap->algo_data;
- sysfs_remove_link(&priv->adap.dev.kobj, "mux_device");
- i2c_del_adapter(adap);
- kfree(priv);
+ muxc->adapter[muxc->adapters] = NULL;
+
+ snprintf(symlink_name, sizeof(symlink_name),
+ "channel-%u", priv->chan_id);
+ sysfs_remove_link(&priv->mux_dev->kobj, symlink_name);
+
+ sysfs_remove_link(&priv->adap.dev.kobj, "mux_device");
+ i2c_del_adapter(adap);
+ kfree(priv);
+ }
}
-EXPORT_SYMBOL_GPL(i2c_del_mux_adapter);
+EXPORT_SYMBOL_GPL(i2c_del_mux_adapters);
MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
MODULE_DESCRIPTION("I2C driver for multiplexed I2C busses");
diff --git a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
index 1e1a479d5b61..e0558e8a0e74 100644
--- a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
+++ b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
@@ -42,7 +42,6 @@
*/
struct i2c_arbitrator_data {
- struct i2c_adapter *child;
int our_gpio;
int our_gpio_release;
int their_gpio;
@@ -205,10 +204,9 @@ static int i2c_arbitrator_probe(struct platform_device *pdev)
}
/* Actually add the mux adapter */
- arb->child = i2c_add_mux_adapter(muxc, dev, 0, 0, 0);
- if (!arb->child) {
+ ret = i2c_add_mux_adapter(muxc, dev, 0, 0, 0);
+ if (ret) {
dev_err(dev, "Failed to add adapter\n");
- ret = -ENODEV;
i2c_put_adapter(muxc->parent);
}
@@ -218,11 +216,9 @@ static int i2c_arbitrator_probe(struct platform_device *pdev)
static int i2c_arbitrator_remove(struct platform_device *pdev)
{
struct i2c_mux_core *muxc = platform_get_drvdata(pdev);
- struct i2c_arbitrator_data *arb = i2c_mux_priv(muxc);
- i2c_del_mux_adapter(arb->child);
+ i2c_del_mux_adapters(muxc);
i2c_put_adapter(muxc->parent);
-
return 0;
}
diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
index d89a0fbca4bc..6bd41ace81d4 100644
--- a/drivers/i2c/muxes/i2c-mux-gpio.c
+++ b/drivers/i2c/muxes/i2c-mux-gpio.c
@@ -18,7 +18,6 @@
#include <linux/of_gpio.h>
struct gpiomux {
- struct i2c_adapter **adap; /* child busses */
struct i2c_mux_gpio_platform_data data;
unsigned gpio_base;
};
@@ -182,14 +181,9 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
muxc->select = i2c_mux_gpio_select;
mux->gpio_base = gpio_base;
- mux->adap = devm_kzalloc(&pdev->dev,
- sizeof(*mux->adap) * mux->data.n_values,
- GFP_KERNEL);
- if (!mux->adap) {
- dev_err(&pdev->dev, "Cannot allocate i2c_adapter structure");
- ret = -ENOMEM;
+ ret = i2c_mux_reserve_adapters(muxc, mux->data.n_values);
+ if (ret)
goto alloc_failed;
- }
if (mux->data.idle != I2C_MUX_GPIO_NO_IDLE) {
initial_state = mux->data.idle;
@@ -222,10 +216,9 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
u32 nr = mux->data.base_nr ? (mux->data.base_nr + i) : 0;
unsigned int class = mux->data.classes ? mux->data.classes[i] : 0;
- mux->adap[i] = i2c_add_mux_adapter(muxc, &pdev->dev, nr,
- mux->data.values[i], class);
- if (!mux->adap[i]) {
- ret = -ENODEV;
+ ret = i2c_add_mux_adapter(muxc, &pdev->dev, nr,
+ mux->data.values[i], class);
+ if (ret) {
dev_err(&pdev->dev, "Failed to add adapter %d\n", i);
goto add_adapter_failed;
}
@@ -237,8 +230,7 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
return 0;
add_adapter_failed:
- for (; i > 0; i--)
- i2c_del_mux_adapter(mux->adap[i - 1]);
+ i2c_del_mux_adapters(muxc);
i = mux->data.n_gpios;
err_request_gpio:
for (; i > 0; i--)
@@ -255,8 +247,7 @@ static int i2c_mux_gpio_remove(struct platform_device *pdev)
struct gpiomux *mux = i2c_mux_priv(muxc);
int i;
- for (i = 0; i < mux->data.n_values; i++)
- i2c_del_mux_adapter(mux->adap[i]);
+ i2c_del_mux_adapters(muxc);
for (i = 0; i < mux->data.n_gpios; i++)
gpio_free(mux->gpio_base + mux->data.gpios[i]);
diff --git a/drivers/i2c/muxes/i2c-mux-pca9541.c b/drivers/i2c/muxes/i2c-mux-pca9541.c
index ae42039459d0..80de0a0977a5 100644
--- a/drivers/i2c/muxes/i2c-mux-pca9541.c
+++ b/drivers/i2c/muxes/i2c-mux-pca9541.c
@@ -74,7 +74,6 @@
struct pca9541 {
struct i2c_client *client;
- struct i2c_adapter *mux_adap;
unsigned long select_timeout;
unsigned long arb_timeout;
};
@@ -332,6 +331,7 @@ static int pca9541_probe(struct i2c_client *client,
struct i2c_mux_core *muxc;
struct pca9541 *data;
int force;
+ int ret;
if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
@@ -361,11 +361,10 @@ static int pca9541_probe(struct i2c_client *client,
force = 0;
if (pdata)
force = pdata->modes[0].adap_id;
- data->mux_adap = i2c_add_mux_adapter(muxc, &client->dev, force, 0, 0);
-
- if (data->mux_adap == NULL) {
+ ret = i2c_add_mux_adapter(muxc, &client->dev, force, 0, 0);
+ if (ret) {
dev_err(&client->dev, "failed to register master selector\n");
- return -ENODEV;
+ return ret;
}
dev_info(&client->dev, "registered master selector for I2C %s\n",
@@ -377,10 +376,8 @@ static int pca9541_probe(struct i2c_client *client,
static int pca9541_remove(struct i2c_client *client)
{
struct i2c_mux_core *muxc = i2c_get_clientdata(client);
- struct pca9541 *data = i2c_mux_priv(muxc);
-
- i2c_del_mux_adapter(data->mux_adap);
+ i2c_del_mux_adapters(muxc);
return 0;
}
diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
index 9e9d708fb2cb..640670b604f5 100644
--- a/drivers/i2c/muxes/i2c-mux-pca954x.c
+++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
@@ -60,7 +60,6 @@ enum pca_type {
struct pca954x {
enum pca_type type;
- struct i2c_adapter *virt_adaps[PCA954X_MAX_NCHANS];
u8 last_chan; /* last register value */
u8 deselect;
@@ -231,6 +230,10 @@ static int pca954x_probe(struct i2c_client *client,
data->type = id->driver_data;
data->last_chan = 0; /* force the first selection */
+ ret = i2c_mux_reserve_adapters(muxc, chips[data->type].nchans);
+ if (ret)
+ return ret;
+
idle_disconnect_dt = of_node &&
of_property_read_bool(of_node, "i2c-mux-idle-disconnect");
@@ -253,12 +256,10 @@ static int pca954x_probe(struct i2c_client *client,
|| idle_disconnect_dt) << num;
}
- data->virt_adaps[num] =
- i2c_add_mux_adapter(muxc, &client->dev,
- force, num, class);
+ ret = i2c_add_mux_adapter(muxc, &client->dev,
+ force, num, class);
- if (data->virt_adaps[num] == NULL) {
- ret = -ENODEV;
+ if (ret) {
dev_err(&client->dev,
"failed to register multiplexed adapter"
" %d as bus %d\n", num, force);
@@ -274,24 +275,15 @@ static int pca954x_probe(struct i2c_client *client,
return 0;
virt_reg_failed:
- for (num--; num >= 0; num--)
- i2c_del_mux_adapter(data->virt_adaps[num]);
+ i2c_del_mux_adapters(muxc);
return ret;
}
static int pca954x_remove(struct i2c_client *client)
{
struct i2c_mux_core *muxc = i2c_get_clientdata(client);
- struct pca954x *data = i2c_mux_priv(muxc);
- const struct chip_desc *chip = &chips[data->type];
- int i;
-
- for (i = 0; i < chip->nchans; ++i)
- if (data->virt_adaps[i]) {
- i2c_del_mux_adapter(data->virt_adaps[i]);
- data->virt_adaps[i] = NULL;
- }
+ i2c_del_mux_adapters(muxc);
return 0;
}
diff --git a/drivers/i2c/muxes/i2c-mux-pinctrl.c b/drivers/i2c/muxes/i2c-mux-pinctrl.c
index e87c8f77037a..3bbb3fb1d693 100644
--- a/drivers/i2c/muxes/i2c-mux-pinctrl.c
+++ b/drivers/i2c/muxes/i2c-mux-pinctrl.c
@@ -31,7 +31,6 @@ struct i2c_mux_pinctrl {
struct pinctrl *pinctrl;
struct pinctrl_state **states;
struct pinctrl_state *state_idle;
- struct i2c_adapter **busses;
};
static int i2c_mux_pinctrl_select(struct i2c_mux_core *muxc, u32 chan)
@@ -163,14 +162,9 @@ static int i2c_mux_pinctrl_probe(struct platform_device *pdev)
goto err;
}
- mux->busses = devm_kzalloc(&pdev->dev,
- sizeof(*mux->busses) * mux->pdata->bus_count,
- GFP_KERNEL);
- if (!mux->busses) {
- dev_err(&pdev->dev, "Cannot allocate busses\n");
- ret = -ENOMEM;
+ ret = i2c_mux_reserve_adapters(muxc, mux->pdata->bus_count);
+ if (ret)
goto err;
- }
mux->pinctrl = devm_pinctrl_get(&pdev->dev);
if (IS_ERR(mux->pinctrl)) {
@@ -218,10 +212,9 @@ static int i2c_mux_pinctrl_probe(struct platform_device *pdev)
u32 bus = mux->pdata->base_bus_num ?
(mux->pdata->base_bus_num + i) : 0;
- mux->busses[i] = i2c_add_mux_adapter(muxc, &pdev->dev,
- bus, i, 0);
- if (!mux->busses[i]) {
- ret = -ENODEV;
+ ret = i2c_add_mux_adapter(muxc, &pdev->dev,
+ bus, i, 0);
+ if (ret) {
dev_err(&pdev->dev, "Failed to add adapter %d\n", i);
goto err_del_adapter;
}
@@ -230,8 +223,7 @@ static int i2c_mux_pinctrl_probe(struct platform_device *pdev)
return 0;
err_del_adapter:
- for (; i > 0; i--)
- i2c_del_mux_adapter(mux->busses[i - 1]);
+ i2c_del_mux_adapters(muxc);
i2c_put_adapter(muxc->parent);
err:
return ret;
@@ -240,14 +232,9 @@ err:
static int i2c_mux_pinctrl_remove(struct platform_device *pdev)
{
struct i2c_mux_core *muxc = platform_get_drvdata(pdev);
- struct i2c_mux_pinctrl *mux = i2c_mux_priv(muxc);
- int i;
-
- for (i = 0; i < mux->pdata->bus_count; i++)
- i2c_del_mux_adapter(mux->busses[i]);
+ i2c_del_mux_adapters(muxc);
i2c_put_adapter(muxc->parent);
-
return 0;
}
diff --git a/drivers/i2c/muxes/i2c-mux-reg.c b/drivers/i2c/muxes/i2c-mux-reg.c
index 3b01e7809a66..5c004ff5b6ad 100644
--- a/drivers/i2c/muxes/i2c-mux-reg.c
+++ b/drivers/i2c/muxes/i2c-mux-reg.c
@@ -21,7 +21,6 @@
#include <linux/slab.h>
struct regmux {
- struct i2c_adapter **adap; /* child busses */
struct i2c_mux_reg_platform_data data;
};
@@ -214,13 +213,9 @@ static int i2c_mux_reg_probe(struct platform_device *pdev)
return -EINVAL;
}
- mux->adap = devm_kzalloc(&pdev->dev,
- sizeof(*mux->adap) * mux->data.n_values,
- GFP_KERNEL);
- if (!mux->adap) {
- dev_err(&pdev->dev, "Cannot allocate i2c_adapter structure");
- return -ENOMEM;
- }
+ ret = i2c_mux_reserve_adapters(muxc, mux->data.n_values);
+ if (ret)
+ return ret;
muxc->select = i2c_mux_reg_select;
if (mux->data.idle_in_use)
@@ -232,11 +227,9 @@ static int i2c_mux_reg_probe(struct platform_device *pdev)
nr = mux->data.base_nr ? (mux->data.base_nr + i) : 0;
class = mux->data.classes ? mux->data.classes[i] : 0;
- mux->adap[i] = i2c_add_mux_adapter(muxc, &pdev->dev,
- nr, mux->data.values[i],
- class);
- if (!mux->adap[i]) {
- ret = -ENODEV;
+ ret = i2c_add_mux_adapter(muxc, &pdev->dev, nr,
+ mux->data.values[i], class);
+ if (ret) {
dev_err(&pdev->dev, "Failed to add adapter %d\n", i);
goto add_adapter_failed;
}
@@ -248,8 +241,7 @@ static int i2c_mux_reg_probe(struct platform_device *pdev)
return 0;
add_adapter_failed:
- for (; i > 0; i--)
- i2c_del_mux_adapter(mux->adap[i - 1]);
+ i2c_del_mux_adapters(muxc);
return ret;
}
@@ -257,12 +249,8 @@ add_adapter_failed:
static int i2c_mux_reg_remove(struct platform_device *pdev)
{
struct i2c_mux_core *muxc = platform_get_drvdata(pdev);
- struct regmux *mux = i2c_mux_priv(muxc);
- int i;
-
- for (i = 0; i < mux->data.n_values; i++)
- i2c_del_mux_adapter(mux->adap[i]);
+ i2c_del_mux_adapters(muxc);
i2c_put_adapter(muxc->parent);
return 0;
diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_acpi.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_acpi.c
index 1c982a56acd5..d433e7b64011 100644
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_acpi.c
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_acpi.c
@@ -182,7 +182,7 @@ int inv_mpu_acpi_create_mux_client(struct inv_mpu6050_state *st)
} else
return 0; /* no secondary addr, which is OK */
}
- st->mux_client = i2c_new_device(st->mux_adapter, &info);
+ st->mux_client = i2c_new_device(st->muxc->adapter[0], &info);
if (!st->mux_client)
return -ENODEV;
diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
index 0a47396bc5be..af9f54a2111d 100644
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
@@ -23,7 +23,6 @@
#include <linux/kfifo.h>
#include <linux/spinlock.h>
#include <linux/iio/iio.h>
-#include <linux/i2c-mux.h>
#include <linux/acpi.h>
#include "inv_mpu_iio.h"
@@ -850,13 +849,9 @@ static int inv_mpu_probe(struct i2c_client *client,
st->muxc->select = inv_mpu6050_select_bypass;
st->muxc->deselect = inv_mpu6050_deselect_bypass;
- st->mux_adapter = i2c_add_mux_adapter(st->muxc,
- &client->dev,
- 0, 0, 0);
- if (!st->mux_adapter) {
- result = -ENODEV;
+ result = i2c_add_mux_adapter(st->muxc, &client->dev, 0, 0, 0);
+ if (result)
goto out_unreg_device;
- }
result = inv_mpu_acpi_create_mux_client(st);
if (result)
@@ -865,7 +860,7 @@ static int inv_mpu_probe(struct i2c_client *client,
return 0;
out_del_mux:
- i2c_del_mux_adapter(st->mux_adapter);
+ i2c_del_mux_adapters(st->muxc);
out_unreg_device:
iio_device_unregister(indio_dev);
out_remove_trigger:
@@ -881,7 +876,7 @@ static int inv_mpu_remove(struct i2c_client *client)
struct inv_mpu6050_state *st = iio_priv(indio_dev);
inv_mpu_acpi_delete_mux_client(st);
- i2c_del_mux_adapter(st->mux_adapter);
+ i2c_del_mux_adapters(st->muxc);
iio_device_unregister(indio_dev);
inv_mpu6050_remove_trigger(st);
iio_triggered_buffer_cleanup(indio_dev);
diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
index d4929db4b40e..61a3a04b84b8 100644
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
@@ -11,6 +11,7 @@
* GNU General Public License for more details.
*/
#include <linux/i2c.h>
+#include <linux/i2c-mux.h>
#include <linux/kfifo.h>
#include <linux/spinlock.h>
#include <linux/iio/iio.h>
@@ -121,7 +122,6 @@ struct inv_mpu6050_state {
spinlock_t time_stamp_lock;
struct i2c_client *client;
struct i2c_mux_core *muxc;
- struct i2c_adapter *mux_adapter;
struct i2c_client *mux_client;
unsigned int powerup_count;
struct inv_mpu6050_platform_data plat_data;
diff --git a/drivers/media/dvb-frontends/m88ds3103.c b/drivers/media/dvb-frontends/m88ds3103.c
index c9f8296ea421..deab5cdba01f 100644
--- a/drivers/media/dvb-frontends/m88ds3103.c
+++ b/drivers/media/dvb-frontends/m88ds3103.c
@@ -1374,7 +1374,7 @@ static struct i2c_adapter *m88ds3103_get_i2c_adapter(struct i2c_client *client)
dev_dbg(&client->dev, "\n");
- return dev->i2c_adapter;
+ return dev->muxc->adapter[0];
}
static int m88ds3103_probe(struct i2c_client *client,
@@ -1476,12 +1476,9 @@ static int m88ds3103_probe(struct i2c_client *client,
dev->muxc->select = m88ds3103_select;
/* create mux i2c adapter for tuner */
- dev->i2c_adapter = i2c_add_mux_adapter(dev->muxc, &client->dev,
- 0, 0, 0);
- if (dev->i2c_adapter == NULL) {
- ret = -ENOMEM;
+ ret = i2c_add_mux_adapter(dev->muxc, &client->dev, 0, 0, 0);
+ if (ret)
goto err_kfree;
- }
/* create dvb_frontend */
memcpy(&dev->fe.ops, &m88ds3103_ops, sizeof(struct dvb_frontend_ops));
@@ -1510,7 +1507,7 @@ static int m88ds3103_remove(struct i2c_client *client)
dev_dbg(&client->dev, "\n");
- i2c_del_mux_adapter(dev->i2c_adapter);
+ i2c_del_mux_adapters(dev->muxc);
kfree(dev);
return 0;
diff --git a/drivers/media/dvb-frontends/m88ds3103_priv.h b/drivers/media/dvb-frontends/m88ds3103_priv.h
index 52d66c566ac1..c5b4e177c6ea 100644
--- a/drivers/media/dvb-frontends/m88ds3103_priv.h
+++ b/drivers/media/dvb-frontends/m88ds3103_priv.h
@@ -43,7 +43,6 @@ struct m88ds3103_dev {
u32 dvbv3_ber; /* for old DVBv3 API read_ber */
bool warm; /* FW running */
struct i2c_mux_core *muxc;
- struct i2c_adapter *i2c_adapter;
/* auto detect chip id to do different config */
u8 chip_id;
/* main mclk is calculated for M88RS6000 dynamically */
diff --git a/drivers/media/dvb-frontends/rtl2830.c b/drivers/media/dvb-frontends/rtl2830.c
index d6330e8d5fa4..9864740722dd 100644
--- a/drivers/media/dvb-frontends/rtl2830.c
+++ b/drivers/media/dvb-frontends/rtl2830.c
@@ -712,7 +712,7 @@ static struct i2c_adapter *rtl2830_get_i2c_adapter(struct i2c_client *client)
dev_dbg(&client->dev, "\n");
- return dev->adapter;
+ return dev->muxc->adapter[0];
}
/*
@@ -874,11 +874,9 @@ static int rtl2830_probe(struct i2c_client *client,
dev->muxc->select = rtl2830_select;
/* create muxed i2c adapter for tuner */
- dev->adapter = i2c_add_mux_adapter(dev->muxc, &client->dev, 0, 0, 0);
- if (dev->adapter == NULL) {
- ret = -ENODEV;
+ ret = i2c_add_mux_adapter(dev->muxc, &client->dev, 0, 0, 0);
+ if (ret)
goto err_regmap_exit;
- }
/* create dvb frontend */
memcpy(&dev->fe.ops, &rtl2830_ops, sizeof(dev->fe.ops));
@@ -908,7 +906,7 @@ static int rtl2830_remove(struct i2c_client *client)
dev_dbg(&client->dev, "\n");
- i2c_del_mux_adapter(dev->adapter);
+ i2c_del_mux_adapters(dev->muxc);
regmap_exit(dev->regmap);
kfree(dev);
diff --git a/drivers/media/dvb-frontends/rtl2830_priv.h b/drivers/media/dvb-frontends/rtl2830_priv.h
index 2169c8d9c99c..da4909543da2 100644
--- a/drivers/media/dvb-frontends/rtl2830_priv.h
+++ b/drivers/media/dvb-frontends/rtl2830_priv.h
@@ -30,7 +30,6 @@ struct rtl2830_dev {
struct i2c_client *client;
struct regmap *regmap;
struct i2c_mux_core *muxc;
- struct i2c_adapter *adapter;
struct dvb_frontend fe;
bool sleeping;
unsigned long filters;
diff --git a/drivers/media/dvb-frontends/rtl2832.c b/drivers/media/dvb-frontends/rtl2832.c
index c8fd990fdae8..99d8dbf66fd7 100644
--- a/drivers/media/dvb-frontends/rtl2832.c
+++ b/drivers/media/dvb-frontends/rtl2832.c
@@ -1074,7 +1074,7 @@ static struct i2c_adapter *rtl2832_get_i2c_adapter(struct i2c_client *client)
struct rtl2832_dev *dev = i2c_get_clientdata(client);
dev_dbg(&client->dev, "\n");
- return dev->i2c_adapter_tuner;
+ return dev->muxc->adapter[0];
}
static int rtl2832_enable_slave_ts(struct i2c_client *client)
@@ -1271,12 +1271,9 @@ static int rtl2832_probe(struct i2c_client *client,
dev->muxc->deselect = rtl2832_deselect;
/* create muxed i2c adapter for demod tuner bus */
- dev->i2c_adapter_tuner = i2c_add_mux_adapter(dev->muxc, &i2c->dev,
- 0, 0, 0);
- if (dev->i2c_adapter_tuner == NULL) {
- ret = -ENODEV;
+ ret = i2c_add_mux_adapter(dev->muxc, &i2c->dev, 0, 0, 0);
+ if (ret)
goto err_regmap_exit;
- }
/* create dvb_frontend */
memcpy(&dev->fe.ops, &rtl2832_ops, sizeof(struct dvb_frontend_ops));
@@ -1311,7 +1308,7 @@ static int rtl2832_remove(struct i2c_client *client)
cancel_delayed_work_sync(&dev->i2c_gate_work);
- i2c_del_mux_adapter(dev->i2c_adapter_tuner);
+ i2c_del_mux_adapters(dev->muxc);
regmap_exit(dev->regmap);
diff --git a/drivers/media/dvb-frontends/rtl2832_priv.h b/drivers/media/dvb-frontends/rtl2832_priv.h
index 2d252bd5b8b1..6b3cd23a2c26 100644
--- a/drivers/media/dvb-frontends/rtl2832_priv.h
+++ b/drivers/media/dvb-frontends/rtl2832_priv.h
@@ -37,7 +37,6 @@ struct rtl2832_dev {
struct regmap_config regmap_config;
struct regmap *regmap;
struct i2c_mux_core *muxc;
- struct i2c_adapter *i2c_adapter_tuner;
struct dvb_frontend fe;
struct delayed_work stat_work;
enum fe_status fe_status;
diff --git a/drivers/media/dvb-frontends/si2168.c b/drivers/media/dvb-frontends/si2168.c
index 5b1872b1bbf4..06aa496cc42c 100644
--- a/drivers/media/dvb-frontends/si2168.c
+++ b/drivers/media/dvb-frontends/si2168.c
@@ -719,16 +719,14 @@ static int si2168_probe(struct i2c_client *client,
dev->muxc->deselect = si2168_deselect;
/* create mux i2c adapter for tuner */
- dev->adapter = i2c_add_mux_adapter(dev->muxc, &client->dev, 0, 0, 0);
- if (dev->adapter == NULL) {
- ret = -ENODEV;
+ ret = i2c_add_mux_adapter(dev->muxc, &client->dev, 0, 0, 0);
+ if (ret)
goto err_kfree;
- }
/* create dvb_frontend */
memcpy(&dev->fe.ops, &si2168_ops, sizeof(struct dvb_frontend_ops));
dev->fe.demodulator_priv = client;
- *config->i2c_adapter = dev->adapter;
+ *config->i2c_adapter = dev->muxc->adapter[0];
*config->fe = &dev->fe;
dev->ts_mode = config->ts_mode;
dev->ts_clock_inv = config->ts_clock_inv;
@@ -752,7 +750,7 @@ static int si2168_remove(struct i2c_client *client)
dev_dbg(&client->dev, "\n");
- i2c_del_mux_adapter(dev->adapter);
+ i2c_del_mux_adapters(dev->muxc);
dev->fe.ops.release = NULL;
dev->fe.demodulator_priv = NULL;
diff --git a/drivers/media/dvb-frontends/si2168_priv.h b/drivers/media/dvb-frontends/si2168_priv.h
index 53efb9d562da..165bf1412063 100644
--- a/drivers/media/dvb-frontends/si2168_priv.h
+++ b/drivers/media/dvb-frontends/si2168_priv.h
@@ -30,7 +30,6 @@
/* state struct */
struct si2168_dev {
struct i2c_mux_core *muxc;
- struct i2c_adapter *adapter;
struct dvb_frontend fe;
enum fe_delivery_system delivery_system;
enum fe_status fe_status;
diff --git a/drivers/media/usb/cx231xx/cx231xx-core.c b/drivers/media/usb/cx231xx/cx231xx-core.c
index d805e192e4ca..7d7b04df6a22 100644
--- a/drivers/media/usb/cx231xx/cx231xx-core.c
+++ b/drivers/media/usb/cx231xx/cx231xx-core.c
@@ -1416,8 +1416,7 @@ EXPORT_SYMBOL_GPL(cx231xx_dev_init);
void cx231xx_dev_uninit(struct cx231xx *dev)
{
/* Un Initialize I2C bus */
- cx231xx_i2c_mux_unregister(dev, 1);
- cx231xx_i2c_mux_unregister(dev, 0);
+ cx231xx_i2c_mux_unregister(dev);
cx231xx_i2c_unregister(&dev->i2c_bus[2]);
cx231xx_i2c_unregister(&dev->i2c_bus[1]);
cx231xx_i2c_unregister(&dev->i2c_bus[0]);
diff --git a/drivers/media/usb/cx231xx/cx231xx-i2c.c b/drivers/media/usb/cx231xx/cx231xx-i2c.c
index 51760bfc7cbc..2b5adb056827 100644
--- a/drivers/media/usb/cx231xx/cx231xx-i2c.c
+++ b/drivers/media/usb/cx231xx/cx231xx-i2c.c
@@ -579,23 +579,23 @@ int cx231xx_i2c_mux_register(struct cx231xx *dev, int mux_no)
{
/* what is the correct mux_dev? */
struct device *mux_dev = dev->dev;
-
- dev->i2c_mux_adap[mux_no] = i2c_add_mux_adapter(dev->muxc,
- mux_dev,
- 0,
- mux_no /* chan_id */,
- 0 /* class */);
- if (!dev->i2c_mux_adap[mux_no])
+ int rc;
+
+ rc = i2c_add_mux_adapter(dev->muxc,
+ mux_dev,
+ 0,
+ mux_no /* chan_id */,
+ 0 /* class */);
+ if (rc)
dev_warn(dev->dev,
"i2c mux %d register FAILED\n", mux_no);
- return 0;
+ return rc;
}
-void cx231xx_i2c_mux_unregister(struct cx231xx *dev, int mux_no)
+void cx231xx_i2c_mux_unregister(struct cx231xx *dev)
{
- i2c_del_mux_adapter(dev->i2c_mux_adap[mux_no]);
- dev->i2c_mux_adap[mux_no] = NULL;
+ i2c_del_mux_adapters(dev->muxc);
}
struct i2c_adapter *cx231xx_get_i2c_adap(struct cx231xx *dev, int i2c_port)
@@ -608,9 +608,9 @@ struct i2c_adapter *cx231xx_get_i2c_adap(struct cx231xx *dev, int i2c_port)
case I2C_2:
return &dev->i2c_bus[2].i2c_adap;
case I2C_1_MUX_1:
- return dev->i2c_mux_adap[0];
+ return dev->muxc->adapter[0];
case I2C_1_MUX_3:
- return dev->i2c_mux_adap[1];
+ return dev->muxc->adapter[1];
default:
return NULL;
}
diff --git a/drivers/media/usb/cx231xx/cx231xx.h b/drivers/media/usb/cx231xx/cx231xx.h
index 72f8188e0b01..8c71fa8d777c 100644
--- a/drivers/media/usb/cx231xx/cx231xx.h
+++ b/drivers/media/usb/cx231xx/cx231xx.h
@@ -762,7 +762,7 @@ int cx231xx_i2c_register(struct cx231xx_i2c *bus);
int cx231xx_i2c_unregister(struct cx231xx_i2c *bus);
int cx231xx_i2c_mux_create(struct cx231xx *dev);
int cx231xx_i2c_mux_register(struct cx231xx *dev, int mux_no);
-void cx231xx_i2c_mux_unregister(struct cx231xx *dev, int mux_no);
+void cx231xx_i2c_mux_unregister(struct cx231xx *dev);
struct i2c_adapter *cx231xx_get_i2c_adap(struct cx231xx *dev, int i2c_port);
/* Internal block control functions */
diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
index a4abd9b588b9..77ccc54cfdc9 100644
--- a/drivers/of/unittest.c
+++ b/drivers/of/unittest.c
@@ -1677,11 +1677,6 @@ static struct i2c_driver unittest_i2c_dev_driver = {
#if IS_BUILTIN(CONFIG_I2C_MUX)
-struct unittest_i2c_mux_data {
- int nchans;
- struct i2c_adapter *adap[];
-};
-
static int unittest_i2c_mux_select_chan(struct i2c_mux_core *muxc, u32 chan)
{
return 0;
@@ -1690,12 +1685,11 @@ static int unittest_i2c_mux_select_chan(struct i2c_mux_core *muxc, u32 chan)
static int unittest_i2c_mux_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
- int ret, i, nchans, size;
+ int ret, i, nchans;
struct device *dev = &client->dev;
struct i2c_adapter *adap = to_i2c_adapter(dev->parent);
struct device_node *np = client->dev.of_node, *child;
struct i2c_mux_core *muxc;
- struct unittest_i2c_mux_data *stm;
u32 reg, max_reg;
dev_dbg(dev, "%s for node @%s\n", __func__, np->full_name);
@@ -1719,20 +1713,19 @@ static int unittest_i2c_mux_probe(struct i2c_client *client,
return -EINVAL;
}
- size = offsetof(struct unittest_i2c_mux_data, adap[nchans]);
- muxc = i2c_mux_alloc(dev, size);
+ muxc = i2c_mux_alloc(dev, 0);
if (!muxc)
return -ENOMEM;
muxc->parent = adap;
muxc->select = unittest_i2c_mux_select_chan;
- stm = i2c_mux_priv(muxc);
- stm->nchans = nchans;
+ ret = i2c_mux_reserve_adapters(muxc, nchans);
+ if (ret)
+ return ret;
for (i = 0; i < nchans; i++) {
- stm->adap[i] = i2c_add_mux_adapter(muxc, dev, 0, i, 0);
- if (!stm->adap[i]) {
+ ret = i2c_add_mux_adapter(muxc, dev, 0, i, 0);
+ if (ret) {
dev_err(dev, "Failed to register mux #%d\n", i);
- for (i--; i >= 0; i--)
- i2c_del_mux_adapter(stm->adap[i]);
+ i2c_del_mux_adapters(muxc);
return -ENODEV;
}
}
@@ -1747,12 +1740,9 @@ static int unittest_i2c_mux_remove(struct i2c_client *client)
struct device *dev = &client->dev;
struct device_node *np = client->dev.of_node;
struct i2c_mux_core *muxc = i2c_get_clientdata(client);
- struct unittest_i2c_mux_data *stm = i2c_mux_priv(muxc);
- int i;
dev_dbg(dev, "%s for node @%s\n", __func__, np->full_name);
- for (i = stm->nchans - 1; i >= 0; i--)
- i2c_del_mux_adapter(stm->adap[i]);
+ i2c_del_mux_adapters(muxc);
return 0;
}
diff --git a/include/linux/i2c-mux.h b/include/linux/i2c-mux.h
index 5cd6e1e664e0..bfcdcc46f2a6 100644
--- a/include/linux/i2c-mux.h
+++ b/include/linux/i2c-mux.h
@@ -29,6 +29,9 @@
struct i2c_mux_core {
struct i2c_adapter *parent;
+ struct i2c_adapter **adapter;
+ int adapters;
+ int max_adapters;
struct device *dev;
void *priv;
@@ -44,18 +47,20 @@ static inline void *i2c_mux_priv(struct i2c_mux_core *muxc)
return muxc->priv;
}
+int i2c_mux_reserve_adapters(struct i2c_mux_core *muxc, int adapters);
+
/*
* Called to create a i2c bus on a multiplexed bus segment.
* The mux_dev and chan_id parameters are passed to the select
* and deselect callback functions to perform hardware-specific
* mux control.
*/
-struct i2c_adapter *i2c_add_mux_adapter(struct i2c_mux_core *muxc,
- struct device *mux_dev,
- u32 force_nr, u32 chan_id,
- unsigned int class);
+int i2c_add_mux_adapter(struct i2c_mux_core *muxc,
+ struct device *mux_dev,
+ u32 force_nr, u32 chan_id,
+ unsigned int class);
-void i2c_del_mux_adapter(struct i2c_adapter *adap);
+void i2c_del_mux_adapters(struct i2c_mux_core *muxc);
#endif /* __KERNEL__ */
--
2.1.4
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v3 4/8] i2c-mux: remove the mux dev pointer from the mux per channel data
2016-01-08 15:04 [PATCH v3 0/8] i2c mux cleanup and locking update Peter Rosin
` (2 preceding siblings ...)
2016-01-08 15:04 ` [PATCH v3 3/8] i2c-mux: move the slave side adapter management " Peter Rosin
@ 2016-01-08 15:04 ` Peter Rosin
2016-01-08 15:04 ` [PATCH v3 5/8] i2c-mux: pinctrl: get rid of the driver private struct device pointer Peter Rosin
` (4 subsequent siblings)
8 siblings, 0 replies; 15+ messages in thread
From: Peter Rosin @ 2016-01-08 15:04 UTC (permalink / raw)
To: Wolfram Sang
Cc: Peter Rosin, Peter Korsgaard, Guenter Roeck, Jonathan Cameron,
Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald,
Antti Palosaari, Mauro Carvalho Chehab, Rob Herring, Frank Rowand,
Grant Likely, Srinivas Pandruvada, Adriana Reus,
Krzysztof Kozlowski, Hans Verkuil, Nicholas Mc Guire,
Olli Salonen, Peter Rosin, linux-i2c, linux-kernel, linux-iio,
linux-media, devicetree
From: Peter Rosin <peda@axentia.se>
The dev pointer is readily available in the mux core struct, no point in
keeping multiple copies around.
The patch also fixes a bug in rtl2832, which attached its mux slave
adapter to the device owning the mux parent adapter instead of
attaching it to its own device.
Signed-off-by: Peter Rosin <peda@axentia.se>
---
drivers/i2c/i2c-mux.c | 24 ++++++++++++------------
drivers/i2c/muxes/i2c-arb-gpio-challenge.c | 2 +-
drivers/i2c/muxes/i2c-mux-gpio.c | 3 +--
drivers/i2c/muxes/i2c-mux-pca9541.c | 2 +-
drivers/i2c/muxes/i2c-mux-pca954x.c | 3 +--
drivers/i2c/muxes/i2c-mux-pinctrl.c | 3 +--
drivers/i2c/muxes/i2c-mux-reg.c | 3 +--
drivers/iio/imu/inv_mpu6050/inv_mpu_core.c | 2 +-
drivers/media/dvb-frontends/m88ds3103.c | 2 +-
drivers/media/dvb-frontends/rtl2830.c | 2 +-
drivers/media/dvb-frontends/rtl2832.c | 2 +-
drivers/media/dvb-frontends/si2168.c | 2 +-
drivers/media/usb/cx231xx/cx231xx-i2c.c | 3 ---
drivers/of/unittest.c | 2 +-
include/linux/i2c-mux.h | 1 -
15 files changed, 24 insertions(+), 32 deletions(-)
diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c
index 3c56625ce13c..9bdebbdcbc61 100644
--- a/drivers/i2c/i2c-mux.c
+++ b/drivers/i2c/i2c-mux.c
@@ -32,7 +32,6 @@ struct i2c_mux_priv {
struct i2c_adapter adap;
struct i2c_algorithm algo;
struct i2c_mux_core *muxc;
- struct device *mux_dev;
u32 chan_id;
};
@@ -139,7 +138,6 @@ struct i2c_mux_core *i2c_mux_alloc(struct device *dev, int sizeof_priv)
EXPORT_SYMBOL_GPL(i2c_mux_alloc);
int i2c_add_mux_adapter(struct i2c_mux_core *muxc,
- struct device *mux_dev,
u32 force_nr, u32 chan_id,
unsigned int class)
{
@@ -164,7 +162,6 @@ int i2c_add_mux_adapter(struct i2c_mux_core *muxc,
/* Set up private adapter data */
priv->muxc = muxc;
- priv->mux_dev = mux_dev;
priv->chan_id = chan_id;
/* Need to do algo dynamically because we don't know ahead
@@ -199,11 +196,11 @@ int i2c_add_mux_adapter(struct i2c_mux_core *muxc,
* Try to populate the mux adapter's of_node, expands to
* nothing if !CONFIG_OF.
*/
- if (mux_dev->of_node) {
+ if (muxc->dev->of_node) {
struct device_node *child;
u32 reg;
- for_each_child_of_node(mux_dev->of_node, child) {
+ for_each_child_of_node(muxc->dev->of_node, child) {
ret = of_property_read_u32(child, "reg", ®);
if (ret)
continue;
@@ -217,8 +214,9 @@ int i2c_add_mux_adapter(struct i2c_mux_core *muxc,
/*
* Associate the mux channel with an ACPI node.
*/
- if (has_acpi_companion(mux_dev))
- acpi_preset_companion(&priv->adap.dev, ACPI_COMPANION(mux_dev),
+ if (has_acpi_companion(muxc->dev))
+ acpi_preset_companion(&priv->adap.dev,
+ ACPI_COMPANION(muxc->dev),
chan_id);
if (force_nr) {
@@ -235,12 +233,14 @@ int i2c_add_mux_adapter(struct i2c_mux_core *muxc,
return ret;
}
- WARN(sysfs_create_link(&priv->adap.dev.kobj, &mux_dev->kobj, "mux_device"),
- "can't create symlink to mux device\n");
+ WARN(sysfs_create_link(&priv->adap.dev.kobj, &muxc->dev->kobj,
+ "mux_device"),
+ "can't create symlink to mux device\n");
snprintf(symlink_name, sizeof(symlink_name), "channel-%u", chan_id);
- WARN(sysfs_create_link(&mux_dev->kobj, &priv->adap.dev.kobj, symlink_name),
- "can't create symlink for channel %u\n", chan_id);
+ WARN(sysfs_create_link(&muxc->dev->kobj, &priv->adap.dev.kobj,
+ symlink_name),
+ "can't create symlink for channel %u\n", chan_id);
dev_info(&parent->dev, "Added multiplexed i2c bus %d\n",
i2c_adapter_id(&priv->adap));
@@ -261,7 +261,7 @@ void i2c_del_mux_adapters(struct i2c_mux_core *muxc)
snprintf(symlink_name, sizeof(symlink_name),
"channel-%u", priv->chan_id);
- sysfs_remove_link(&priv->mux_dev->kobj, symlink_name);
+ sysfs_remove_link(&muxc->dev->kobj, symlink_name);
sysfs_remove_link(&priv->adap.dev.kobj, "mux_device");
i2c_del_adapter(adap);
diff --git a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
index e0558e8a0e74..c2bc18c7921f 100644
--- a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
+++ b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
@@ -204,7 +204,7 @@ static int i2c_arbitrator_probe(struct platform_device *pdev)
}
/* Actually add the mux adapter */
- ret = i2c_add_mux_adapter(muxc, dev, 0, 0, 0);
+ ret = i2c_add_mux_adapter(muxc, 0, 0, 0);
if (ret) {
dev_err(dev, "Failed to add adapter\n");
i2c_put_adapter(muxc->parent);
diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
index 6bd41ace81d4..e800c4597fa4 100644
--- a/drivers/i2c/muxes/i2c-mux-gpio.c
+++ b/drivers/i2c/muxes/i2c-mux-gpio.c
@@ -216,8 +216,7 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
u32 nr = mux->data.base_nr ? (mux->data.base_nr + i) : 0;
unsigned int class = mux->data.classes ? mux->data.classes[i] : 0;
- ret = i2c_add_mux_adapter(muxc, &pdev->dev, nr,
- mux->data.values[i], class);
+ ret = i2c_add_mux_adapter(muxc, nr, mux->data.values[i], class);
if (ret) {
dev_err(&pdev->dev, "Failed to add adapter %d\n", i);
goto add_adapter_failed;
diff --git a/drivers/i2c/muxes/i2c-mux-pca9541.c b/drivers/i2c/muxes/i2c-mux-pca9541.c
index 80de0a0977a5..0e18d25334b5 100644
--- a/drivers/i2c/muxes/i2c-mux-pca9541.c
+++ b/drivers/i2c/muxes/i2c-mux-pca9541.c
@@ -361,7 +361,7 @@ static int pca9541_probe(struct i2c_client *client,
force = 0;
if (pdata)
force = pdata->modes[0].adap_id;
- ret = i2c_add_mux_adapter(muxc, &client->dev, force, 0, 0);
+ ret = i2c_add_mux_adapter(muxc, force, 0, 0);
if (ret) {
dev_err(&client->dev, "failed to register master selector\n");
return ret;
diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
index 640670b604f5..2d15325b6282 100644
--- a/drivers/i2c/muxes/i2c-mux-pca954x.c
+++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
@@ -256,8 +256,7 @@ static int pca954x_probe(struct i2c_client *client,
|| idle_disconnect_dt) << num;
}
- ret = i2c_add_mux_adapter(muxc, &client->dev,
- force, num, class);
+ ret = i2c_add_mux_adapter(muxc, force, num, class);
if (ret) {
dev_err(&client->dev,
diff --git a/drivers/i2c/muxes/i2c-mux-pinctrl.c b/drivers/i2c/muxes/i2c-mux-pinctrl.c
index 3bbb3fb1d693..0dc912898813 100644
--- a/drivers/i2c/muxes/i2c-mux-pinctrl.c
+++ b/drivers/i2c/muxes/i2c-mux-pinctrl.c
@@ -212,8 +212,7 @@ static int i2c_mux_pinctrl_probe(struct platform_device *pdev)
u32 bus = mux->pdata->base_bus_num ?
(mux->pdata->base_bus_num + i) : 0;
- ret = i2c_add_mux_adapter(muxc, &pdev->dev,
- bus, i, 0);
+ ret = i2c_add_mux_adapter(muxc, bus, i, 0);
if (ret) {
dev_err(&pdev->dev, "Failed to add adapter %d\n", i);
goto err_del_adapter;
diff --git a/drivers/i2c/muxes/i2c-mux-reg.c b/drivers/i2c/muxes/i2c-mux-reg.c
index 5c004ff5b6ad..3c919e49260c 100644
--- a/drivers/i2c/muxes/i2c-mux-reg.c
+++ b/drivers/i2c/muxes/i2c-mux-reg.c
@@ -227,8 +227,7 @@ static int i2c_mux_reg_probe(struct platform_device *pdev)
nr = mux->data.base_nr ? (mux->data.base_nr + i) : 0;
class = mux->data.classes ? mux->data.classes[i] : 0;
- ret = i2c_add_mux_adapter(muxc, &pdev->dev, nr,
- mux->data.values[i], class);
+ ret = i2c_add_mux_adapter(muxc, nr, mux->data.values[i], class);
if (ret) {
dev_err(&pdev->dev, "Failed to add adapter %d\n", i);
goto add_adapter_failed;
diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
index af9f54a2111d..744c8760c1fe 100644
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
@@ -849,7 +849,7 @@ static int inv_mpu_probe(struct i2c_client *client,
st->muxc->select = inv_mpu6050_select_bypass;
st->muxc->deselect = inv_mpu6050_deselect_bypass;
- result = i2c_add_mux_adapter(st->muxc, &client->dev, 0, 0, 0);
+ result = i2c_add_mux_adapter(st->muxc, 0, 0, 0);
if (result)
goto out_unreg_device;
diff --git a/drivers/media/dvb-frontends/m88ds3103.c b/drivers/media/dvb-frontends/m88ds3103.c
index deab5cdba01f..45ad3ef82b4f 100644
--- a/drivers/media/dvb-frontends/m88ds3103.c
+++ b/drivers/media/dvb-frontends/m88ds3103.c
@@ -1476,7 +1476,7 @@ static int m88ds3103_probe(struct i2c_client *client,
dev->muxc->select = m88ds3103_select;
/* create mux i2c adapter for tuner */
- ret = i2c_add_mux_adapter(dev->muxc, &client->dev, 0, 0, 0);
+ ret = i2c_add_mux_adapter(dev->muxc, 0, 0, 0);
if (ret)
goto err_kfree;
diff --git a/drivers/media/dvb-frontends/rtl2830.c b/drivers/media/dvb-frontends/rtl2830.c
index 9864740722dd..1da8d2e22983 100644
--- a/drivers/media/dvb-frontends/rtl2830.c
+++ b/drivers/media/dvb-frontends/rtl2830.c
@@ -874,7 +874,7 @@ static int rtl2830_probe(struct i2c_client *client,
dev->muxc->select = rtl2830_select;
/* create muxed i2c adapter for tuner */
- ret = i2c_add_mux_adapter(dev->muxc, &client->dev, 0, 0, 0);
+ ret = i2c_add_mux_adapter(dev->muxc, 0, 0, 0);
if (ret)
goto err_regmap_exit;
diff --git a/drivers/media/dvb-frontends/rtl2832.c b/drivers/media/dvb-frontends/rtl2832.c
index 99d8dbf66fd7..c586150623f7 100644
--- a/drivers/media/dvb-frontends/rtl2832.c
+++ b/drivers/media/dvb-frontends/rtl2832.c
@@ -1271,7 +1271,7 @@ static int rtl2832_probe(struct i2c_client *client,
dev->muxc->deselect = rtl2832_deselect;
/* create muxed i2c adapter for demod tuner bus */
- ret = i2c_add_mux_adapter(dev->muxc, &i2c->dev, 0, 0, 0);
+ ret = i2c_add_mux_adapter(dev->muxc, 0, 0, 0);
if (ret)
goto err_regmap_exit;
diff --git a/drivers/media/dvb-frontends/si2168.c b/drivers/media/dvb-frontends/si2168.c
index 06aa496cc42c..ae217b5e6618 100644
--- a/drivers/media/dvb-frontends/si2168.c
+++ b/drivers/media/dvb-frontends/si2168.c
@@ -719,7 +719,7 @@ static int si2168_probe(struct i2c_client *client,
dev->muxc->deselect = si2168_deselect;
/* create mux i2c adapter for tuner */
- ret = i2c_add_mux_adapter(dev->muxc, &client->dev, 0, 0, 0);
+ ret = i2c_add_mux_adapter(dev->muxc, 0, 0, 0);
if (ret)
goto err_kfree;
diff --git a/drivers/media/usb/cx231xx/cx231xx-i2c.c b/drivers/media/usb/cx231xx/cx231xx-i2c.c
index 2b5adb056827..bfa63cf69235 100644
--- a/drivers/media/usb/cx231xx/cx231xx-i2c.c
+++ b/drivers/media/usb/cx231xx/cx231xx-i2c.c
@@ -577,12 +577,9 @@ int cx231xx_i2c_mux_create(struct cx231xx *dev)
int cx231xx_i2c_mux_register(struct cx231xx *dev, int mux_no)
{
- /* what is the correct mux_dev? */
- struct device *mux_dev = dev->dev;
int rc;
rc = i2c_add_mux_adapter(dev->muxc,
- mux_dev,
0,
mux_no /* chan_id */,
0 /* class */);
diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
index 77ccc54cfdc9..46897ed4e396 100644
--- a/drivers/of/unittest.c
+++ b/drivers/of/unittest.c
@@ -1722,7 +1722,7 @@ static int unittest_i2c_mux_probe(struct i2c_client *client,
if (ret)
return ret;
for (i = 0; i < nchans; i++) {
- ret = i2c_add_mux_adapter(muxc, dev, 0, i, 0);
+ ret = i2c_add_mux_adapter(muxc, 0, i, 0);
if (ret) {
dev_err(dev, "Failed to register mux #%d\n", i);
i2c_del_mux_adapters(muxc);
diff --git a/include/linux/i2c-mux.h b/include/linux/i2c-mux.h
index bfcdcc46f2a6..d88e0a3b6768 100644
--- a/include/linux/i2c-mux.h
+++ b/include/linux/i2c-mux.h
@@ -56,7 +56,6 @@ int i2c_mux_reserve_adapters(struct i2c_mux_core *muxc, int adapters);
* mux control.
*/
int i2c_add_mux_adapter(struct i2c_mux_core *muxc,
- struct device *mux_dev,
u32 force_nr, u32 chan_id,
unsigned int class);
--
2.1.4
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v3 5/8] i2c-mux: pinctrl: get rid of the driver private struct device pointer
2016-01-08 15:04 [PATCH v3 0/8] i2c mux cleanup and locking update Peter Rosin
` (3 preceding siblings ...)
2016-01-08 15:04 ` [PATCH v3 4/8] i2c-mux: remove the mux dev pointer from the mux per channel data Peter Rosin
@ 2016-01-08 15:04 ` Peter Rosin
2016-01-08 15:04 ` [PATCH v3 6/8] i2c: allow adapter drivers to override the adapter locking Peter Rosin
` (3 subsequent siblings)
8 siblings, 0 replies; 15+ messages in thread
From: Peter Rosin @ 2016-01-08 15:04 UTC (permalink / raw)
To: Wolfram Sang
Cc: Peter Rosin, Peter Korsgaard, Guenter Roeck, Jonathan Cameron,
Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald,
Antti Palosaari, Mauro Carvalho Chehab, Rob Herring, Frank Rowand,
Grant Likely, Srinivas Pandruvada, Adriana Reus,
Krzysztof Kozlowski, Hans Verkuil, Nicholas Mc Guire,
Olli Salonen, Peter Rosin, linux-i2c, linux-kernel, linux-iio,
linux-media, devicetree
From: Peter Rosin <peda@axentia.se>
There is a copy of the device pointer in the mux core.
Signed-off-by: Peter Rosin <peda@axentia.se>
---
drivers/i2c/muxes/i2c-mux-pinctrl.c | 23 ++++++++---------------
1 file changed, 8 insertions(+), 15 deletions(-)
diff --git a/drivers/i2c/muxes/i2c-mux-pinctrl.c b/drivers/i2c/muxes/i2c-mux-pinctrl.c
index 0dc912898813..38129850cbe4 100644
--- a/drivers/i2c/muxes/i2c-mux-pinctrl.c
+++ b/drivers/i2c/muxes/i2c-mux-pinctrl.c
@@ -26,7 +26,6 @@
#include <linux/of.h>
struct i2c_mux_pinctrl {
- struct device *dev;
struct i2c_mux_pinctrl_platform_data *pdata;
struct pinctrl *pinctrl;
struct pinctrl_state **states;
@@ -51,6 +50,7 @@ static int i2c_mux_pinctrl_deselect(struct i2c_mux_core *muxc, u32 chan)
static int i2c_mux_pinctrl_parse_dt(struct i2c_mux_pinctrl *mux,
struct platform_device *pdev)
{
+ struct i2c_mux_core *muxc = platform_get_drvdata(pdev);
struct device_node *np = pdev->dev.of_node;
int num_names, i, ret;
struct device_node *adapter_np;
@@ -60,15 +60,12 @@ static int i2c_mux_pinctrl_parse_dt(struct i2c_mux_pinctrl *mux,
return 0;
mux->pdata = devm_kzalloc(&pdev->dev, sizeof(*mux->pdata), GFP_KERNEL);
- if (!mux->pdata) {
- dev_err(mux->dev,
- "Cannot allocate i2c_mux_pinctrl_platform_data\n");
+ if (!mux->pdata)
return -ENOMEM;
- }
num_names = of_property_count_strings(np, "pinctrl-names");
if (num_names < 0) {
- dev_err(mux->dev, "Cannot parse pinctrl-names: %d\n",
+ dev_err(muxc->dev, "Cannot parse pinctrl-names: %d\n",
num_names);
return num_names;
}
@@ -76,23 +73,21 @@ static int i2c_mux_pinctrl_parse_dt(struct i2c_mux_pinctrl *mux,
mux->pdata->pinctrl_states = devm_kzalloc(&pdev->dev,
sizeof(*mux->pdata->pinctrl_states) * num_names,
GFP_KERNEL);
- if (!mux->pdata->pinctrl_states) {
- dev_err(mux->dev, "Cannot allocate pinctrl_states\n");
+ if (!mux->pdata->pinctrl_states)
return -ENOMEM;
- }
for (i = 0; i < num_names; i++) {
ret = of_property_read_string_index(np, "pinctrl-names", i,
&mux->pdata->pinctrl_states[mux->pdata->bus_count]);
if (ret < 0) {
- dev_err(mux->dev, "Cannot parse pinctrl-names: %d\n",
+ dev_err(muxc->dev, "Cannot parse pinctrl-names: %d\n",
ret);
return ret;
}
if (!strcmp(mux->pdata->pinctrl_states[mux->pdata->bus_count],
"idle")) {
if (i != num_names - 1) {
- dev_err(mux->dev, "idle state must be last\n");
+ dev_err(muxc->dev, "idle state must be last\n");
return -EINVAL;
}
mux->pdata->pinctrl_state_idle = "idle";
@@ -103,13 +98,13 @@ static int i2c_mux_pinctrl_parse_dt(struct i2c_mux_pinctrl *mux,
adapter_np = of_parse_phandle(np, "i2c-parent", 0);
if (!adapter_np) {
- dev_err(mux->dev, "Cannot parse i2c-parent\n");
+ dev_err(muxc->dev, "Cannot parse i2c-parent\n");
return -ENODEV;
}
adapter = of_find_i2c_adapter_by_node(adapter_np);
of_node_put(adapter_np);
if (!adapter) {
- dev_err(mux->dev, "Cannot find parent bus\n");
+ dev_err(muxc->dev, "Cannot find parent bus\n");
return -EPROBE_DEFER;
}
mux->pdata->parent_bus_num = i2c_adapter_id(adapter);
@@ -139,8 +134,6 @@ static int i2c_mux_pinctrl_probe(struct platform_device *pdev)
mux = i2c_mux_priv(muxc);
platform_set_drvdata(pdev, muxc);
- mux->dev = &pdev->dev;
-
mux->pdata = dev_get_platdata(&pdev->dev);
if (!mux->pdata) {
ret = i2c_mux_pinctrl_parse_dt(mux, pdev);
--
2.1.4
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v3 6/8] i2c: allow adapter drivers to override the adapter locking
2016-01-08 15:04 [PATCH v3 0/8] i2c mux cleanup and locking update Peter Rosin
` (4 preceding siblings ...)
2016-01-08 15:04 ` [PATCH v3 5/8] i2c-mux: pinctrl: get rid of the driver private struct device pointer Peter Rosin
@ 2016-01-08 15:04 ` Peter Rosin
2016-01-08 15:04 ` [PATCH v3 7/8] i2c: muxes always lock the parent adapter Peter Rosin
` (2 subsequent siblings)
8 siblings, 0 replies; 15+ messages in thread
From: Peter Rosin @ 2016-01-08 15:04 UTC (permalink / raw)
To: Wolfram Sang
Cc: Peter Rosin, Peter Korsgaard, Guenter Roeck, Jonathan Cameron,
Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald,
Antti Palosaari, Mauro Carvalho Chehab, Rob Herring, Frank Rowand,
Grant Likely, Srinivas Pandruvada, Adriana Reus,
Krzysztof Kozlowski, Hans Verkuil, Nicholas Mc Guire,
Olli Salonen, Peter Rosin, linux-i2c, linux-kernel, linux-iio,
linux-media, devicetree
From: Peter Rosin <peda@axentia.se>
Add i2c_lock_bus() and i2c_unlock_bus(), which call the new lock_bus and
unlock_bus ops in the adapter. These funcs/ops take an additional flags
argument that indicates for what purpose the adapter is locked.
There are two flags, I2C_LOCK_ADAPTER and I2C_LOCK_SEGMENT, but they are
both implemented the same. For now. Locking the adapter means that the
whole bus is locked, locking the segment means that only the current bus
segment is locked (i.e. i2c traffic on the parent side of mux is still
allowed even if the child side of the mux is locked.
Also support a trylock_bus op (but no function to call it, as it is not
expected to be needed outside of the i2c core).
Implement i2c_lock_adapter/i2c_unlock_adapter in terms of the new locking
scheme (i.e. lock with the I2C_LOCK_ADAPTER flag).
Annotate some of the locking with explicit I2C_LOCK_SEGMENT flags.
Signed-off-by: Peter Rosin <peda@axentia.se>
---
drivers/i2c/i2c-core.c | 40 ++++++++++++++++++++++------------------
include/linux/i2c.h | 28 ++++++++++++++++++++++++++--
2 files changed, 48 insertions(+), 20 deletions(-)
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index ba8eb087f224..34a7748b4652 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -958,10 +958,10 @@ static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr)
}
/**
- * i2c_lock_adapter - Get exclusive access to an I2C bus segment
+ * i2c_adapter_lock_bus - Get exclusive access to an I2C bus segment
* @adapter: Target I2C bus segment
*/
-void i2c_lock_adapter(struct i2c_adapter *adapter)
+static void i2c_adapter_lock_bus(struct i2c_adapter *adapter, int flags)
{
struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter);
@@ -970,27 +970,26 @@ void i2c_lock_adapter(struct i2c_adapter *adapter)
else
rt_mutex_lock(&adapter->bus_lock);
}
-EXPORT_SYMBOL_GPL(i2c_lock_adapter);
/**
- * i2c_trylock_adapter - Try to get exclusive access to an I2C bus segment
+ * i2c_adapter_trylock_bus - Try to get exclusive access to an I2C bus segment
* @adapter: Target I2C bus segment
*/
-static int i2c_trylock_adapter(struct i2c_adapter *adapter)
+static int i2c_adapter_trylock_bus(struct i2c_adapter *adapter, int flags)
{
struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter);
if (parent)
- return i2c_trylock_adapter(parent);
+ return parent->trylock_bus(parent, flags);
else
return rt_mutex_trylock(&adapter->bus_lock);
}
/**
- * i2c_unlock_adapter - Release exclusive access to an I2C bus segment
+ * i2c_adapter_unlock_bus - Release exclusive access to an I2C bus segment
* @adapter: Target I2C bus segment
*/
-void i2c_unlock_adapter(struct i2c_adapter *adapter)
+static void i2c_adapter_unlock_bus(struct i2c_adapter *adapter, int flags)
{
struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter);
@@ -999,7 +998,6 @@ void i2c_unlock_adapter(struct i2c_adapter *adapter)
else
rt_mutex_unlock(&adapter->bus_lock);
}
-EXPORT_SYMBOL_GPL(i2c_unlock_adapter);
static void i2c_dev_set_name(struct i2c_adapter *adap,
struct i2c_client *client)
@@ -1545,6 +1543,12 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
return -EINVAL;
}
+ if (!adap->lock_bus) {
+ adap->lock_bus = i2c_adapter_lock_bus;
+ adap->trylock_bus = i2c_adapter_trylock_bus;
+ adap->unlock_bus = i2c_adapter_unlock_bus;
+ }
+
rt_mutex_init(&adap->bus_lock);
mutex_init(&adap->userspace_clients_lock);
INIT_LIST_HEAD(&adap->userspace_clients);
@@ -2254,16 +2258,16 @@ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
#endif
if (in_atomic() || irqs_disabled()) {
- ret = i2c_trylock_adapter(adap);
+ ret = adap->trylock_bus(adap, I2C_LOCK_SEGMENT);
if (!ret)
/* I2C activity is ongoing. */
return -EAGAIN;
} else {
- i2c_lock_adapter(adap);
+ i2c_lock_bus(adap, I2C_LOCK_SEGMENT);
}
ret = __i2c_transfer(adap, msgs, num);
- i2c_unlock_adapter(adap);
+ i2c_unlock_bus(adap, I2C_LOCK_SEGMENT);
return ret;
} else {
@@ -3038,7 +3042,7 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags,
flags &= I2C_M_TEN | I2C_CLIENT_PEC | I2C_CLIENT_SCCB;
if (adapter->algo->smbus_xfer) {
- i2c_lock_adapter(adapter);
+ i2c_lock_bus(adapter, I2C_LOCK_SEGMENT);
/* Retry automatically on arbitration loss */
orig_jiffies = jiffies;
@@ -3052,7 +3056,7 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags,
orig_jiffies + adapter->timeout))
break;
}
- i2c_unlock_adapter(adapter);
+ i2c_unlock_bus(adapter, I2C_LOCK_SEGMENT);
if (res != -EOPNOTSUPP || !adapter->algo->master_xfer)
goto trace;
@@ -3163,9 +3167,9 @@ int i2c_slave_register(struct i2c_client *client, i2c_slave_cb_t slave_cb)
client->slave_cb = slave_cb;
- i2c_lock_adapter(client->adapter);
+ i2c_lock_bus(client->adapter, I2C_LOCK_SEGMENT);
ret = client->adapter->algo->reg_slave(client);
- i2c_unlock_adapter(client->adapter);
+ i2c_unlock_bus(client->adapter, I2C_LOCK_SEGMENT);
if (ret) {
client->slave_cb = NULL;
@@ -3185,9 +3189,9 @@ int i2c_slave_unregister(struct i2c_client *client)
return -EOPNOTSUPP;
}
- i2c_lock_adapter(client->adapter);
+ i2c_lock_bus(client->adapter, I2C_LOCK_SEGMENT);
ret = client->adapter->algo->unreg_slave(client);
- i2c_unlock_adapter(client->adapter);
+ i2c_unlock_bus(client->adapter, I2C_LOCK_SEGMENT);
if (ret == 0)
client->slave_cb = NULL;
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 768063baafbf..8040b48aef75 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -520,6 +520,10 @@ struct i2c_adapter {
struct i2c_bus_recovery_info *bus_recovery_info;
const struct i2c_adapter_quirks *quirks;
+
+ void (*lock_bus)(struct i2c_adapter *, int flags);
+ int (*trylock_bus)(struct i2c_adapter *, int flags);
+ void (*unlock_bus)(struct i2c_adapter *, int flags);
};
#define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
@@ -549,8 +553,28 @@ i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter)
int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *));
/* Adapter locking functions, exported for shared pin cases */
-void i2c_lock_adapter(struct i2c_adapter *);
-void i2c_unlock_adapter(struct i2c_adapter *);
+#define I2C_LOCK_ADAPTER 0x01
+#define I2C_LOCK_SEGMENT 0x02
+static inline void
+i2c_lock_bus(struct i2c_adapter *adapter, int flags)
+{
+ adapter->lock_bus(adapter, flags);
+}
+static inline void
+i2c_unlock_bus(struct i2c_adapter *adapter, int flags)
+{
+ adapter->unlock_bus(adapter, flags);
+}
+static inline void
+i2c_lock_adapter(struct i2c_adapter *adapter)
+{
+ i2c_lock_bus(adapter, I2C_LOCK_ADAPTER);
+}
+static inline void
+i2c_unlock_adapter(struct i2c_adapter *adapter)
+{
+ i2c_unlock_bus(adapter, I2C_LOCK_ADAPTER);
+}
/*flags for the client struct: */
#define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */
--
2.1.4
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v3 7/8] i2c: muxes always lock the parent adapter
2016-01-08 15:04 [PATCH v3 0/8] i2c mux cleanup and locking update Peter Rosin
` (5 preceding siblings ...)
2016-01-08 15:04 ` [PATCH v3 6/8] i2c: allow adapter drivers to override the adapter locking Peter Rosin
@ 2016-01-08 15:04 ` Peter Rosin
2016-01-08 15:04 ` [PATCH v3 8/8] i2c-mux: relax locking of the top i2c adapter during i2c controlled muxing Peter Rosin
2016-03-02 17:29 ` [PATCH v3 0/8] i2c mux cleanup and locking update Wolfram Sang
8 siblings, 0 replies; 15+ messages in thread
From: Peter Rosin @ 2016-01-08 15:04 UTC (permalink / raw)
To: Wolfram Sang
Cc: Peter Rosin, Peter Korsgaard, Guenter Roeck, Jonathan Cameron,
Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald,
Antti Palosaari, Mauro Carvalho Chehab, Rob Herring, Frank Rowand,
Grant Likely, Srinivas Pandruvada, Adriana Reus,
Krzysztof Kozlowski, Hans Verkuil, Nicholas Mc Guire,
Olli Salonen, Peter Rosin, linux-i2c, linux-kernel, linux-iio,
linux-media, devicetree
From: Peter Rosin <peda@axentia.se>
Instead of checking for i2c parent adapters for every lock/unlock, simply
override the locking for muxes to always lock/unlock the parent adapter
directly.
Signed-off-by: Peter Rosin <peda@axentia.se>
---
drivers/i2c/i2c-core.c | 21 +++------------------
drivers/i2c/i2c-mux.c | 27 +++++++++++++++++++++++++++
2 files changed, 30 insertions(+), 18 deletions(-)
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 34a7748b4652..4683777f81ca 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -963,12 +963,7 @@ static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr)
*/
static void i2c_adapter_lock_bus(struct i2c_adapter *adapter, int flags)
{
- struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter);
-
- if (parent)
- i2c_lock_adapter(parent);
- else
- rt_mutex_lock(&adapter->bus_lock);
+ rt_mutex_lock(&adapter->bus_lock);
}
/**
@@ -977,12 +972,7 @@ static void i2c_adapter_lock_bus(struct i2c_adapter *adapter, int flags)
*/
static int i2c_adapter_trylock_bus(struct i2c_adapter *adapter, int flags)
{
- struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter);
-
- if (parent)
- return parent->trylock_bus(parent, flags);
- else
- return rt_mutex_trylock(&adapter->bus_lock);
+ return rt_mutex_trylock(&adapter->bus_lock);
}
/**
@@ -991,12 +981,7 @@ static int i2c_adapter_trylock_bus(struct i2c_adapter *adapter, int flags)
*/
static void i2c_adapter_unlock_bus(struct i2c_adapter *adapter, int flags)
{
- struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter);
-
- if (parent)
- i2c_unlock_adapter(parent);
- else
- rt_mutex_unlock(&adapter->bus_lock);
+ rt_mutex_unlock(&adapter->bus_lock);
}
static void i2c_dev_set_name(struct i2c_adapter *adap,
diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c
index 9bdebbdcbc61..fcfe51b023c0 100644
--- a/drivers/i2c/i2c-mux.c
+++ b/drivers/i2c/i2c-mux.c
@@ -98,6 +98,30 @@ static unsigned int i2c_mux_parent_classes(struct i2c_adapter *parent)
return class;
}
+static void i2c_parent_lock_bus(struct i2c_adapter *adapter, int flags)
+{
+ struct i2c_mux_priv *priv = adapter->algo_data;
+ struct i2c_adapter *parent = priv->muxc->parent;
+
+ parent->lock_bus(parent, flags);
+}
+
+static int i2c_parent_trylock_bus(struct i2c_adapter *adapter, int flags)
+{
+ struct i2c_mux_priv *priv = adapter->algo_data;
+ struct i2c_adapter *parent = priv->muxc->parent;
+
+ return parent->trylock_bus(parent, flags);
+}
+
+static void i2c_parent_unlock_bus(struct i2c_adapter *adapter, int flags)
+{
+ struct i2c_mux_priv *priv = adapter->algo_data;
+ struct i2c_adapter *parent = priv->muxc->parent;
+
+ parent->unlock_bus(parent, flags);
+}
+
int i2c_mux_reserve_adapters(struct i2c_mux_core *muxc, int adapters)
{
struct i2c_adapter **adapter;
@@ -183,6 +207,9 @@ int i2c_add_mux_adapter(struct i2c_mux_core *muxc,
priv->adap.retries = parent->retries;
priv->adap.timeout = parent->timeout;
priv->adap.quirks = parent->quirks;
+ priv->adap.lock_bus = i2c_parent_lock_bus;
+ priv->adap.trylock_bus = i2c_parent_trylock_bus;
+ priv->adap.unlock_bus = i2c_parent_unlock_bus;
/* Sanity check on class */
if (i2c_mux_parent_classes(parent) & class)
--
2.1.4
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v3 8/8] i2c-mux: relax locking of the top i2c adapter during i2c controlled muxing
2016-01-08 15:04 [PATCH v3 0/8] i2c mux cleanup and locking update Peter Rosin
` (6 preceding siblings ...)
2016-01-08 15:04 ` [PATCH v3 7/8] i2c: muxes always lock the parent adapter Peter Rosin
@ 2016-01-08 15:04 ` Peter Rosin
2016-03-02 17:29 ` [PATCH v3 0/8] i2c mux cleanup and locking update Wolfram Sang
8 siblings, 0 replies; 15+ messages in thread
From: Peter Rosin @ 2016-01-08 15:04 UTC (permalink / raw)
To: Wolfram Sang
Cc: Peter Rosin, Peter Korsgaard, Guenter Roeck, Jonathan Cameron,
Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald,
Antti Palosaari, Mauro Carvalho Chehab, Rob Herring, Frank Rowand,
Grant Likely, Srinivas Pandruvada, Adriana Reus,
Krzysztof Kozlowski, Hans Verkuil, Nicholas Mc Guire,
Olli Salonen, Peter Rosin, linux-i2c, linux-kernel, linux-iio,
linux-media, devicetree
From: Peter Rosin <peda@axentia.se>
With a i2c topology like the following
GPIO ---| ------ BAT1
| v /
I2C -----+----------+---- MUX
| \
EEPROM ------ BAT2
there is a locking problem with the GPIO controller since it is a client
on the same i2c bus that it muxes. Transfers to the mux clients (e.g. BAT1)
will lock the whole i2c bus prior to attempting to switch the mux to the
correct i2c segment. In the above case, the GPIO device is an I/O expander
with an i2c interface, and since the GPIO subsystem knows nothing (and
rightfully so) about the lockless needs of the i2c mux code, this results
in a deadlock when the GPIO driver issues i2c transfers to modify the
mux.
So, observing that while it is needed to have the i2c bus locked during the
actual MUX update in order to avoid random garbage on the slave side, it
is not strictly a must to have it locked over the whole sequence of a full
select-transfer-deselect mux client operation. The mux itself needs to be
locked, so transfers to clients behind the mux are serialized, and the mux
needs to be stable during all i2c traffic (otherwise individual mux slave
segments might see garbage, or worse).
Add code to i2c-mux-gpio and i2c-mux-pinctrl that checks if all involved
gpio/pinctrl devices have a parent that is an i2c adapter in the same
adapter tree that is muxed.
Modify the i2c mux locking so that muxes that are "i2c-controlled" locks
the mux instead of the whole i2c bus when there is a transfer to the slave
side of the mux. This lock serializes transfers to the slave side of the
mux.
Modify the select-transfer-deselect code for "i2c-controlled" muxes so
that each of the select-transfer-deselect ops locks the mux parent
adapter individually.
Signed-off-by: Peter Rosin <peda@axentia.se>
---
drivers/i2c/i2c-mux.c | 134 ++++++++++++++++++++++++++++++++++--
drivers/i2c/muxes/i2c-mux-gpio.c | 19 +++++
drivers/i2c/muxes/i2c-mux-pinctrl.c | 39 +++++++++++
include/linux/i2c-mux.h | 4 ++
4 files changed, 189 insertions(+), 7 deletions(-)
diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c
index fcfe51b023c0..85dd837164a8 100644
--- a/drivers/i2c/i2c-mux.c
+++ b/drivers/i2c/i2c-mux.c
@@ -54,6 +54,25 @@ static int i2c_mux_master_xfer(struct i2c_adapter *adap,
return ret;
}
+static int __i2c_mux_master_xfer(struct i2c_adapter *adap,
+ struct i2c_msg msgs[], int num)
+{
+ struct i2c_mux_priv *priv = adap->algo_data;
+ struct i2c_mux_core *muxc = priv->muxc;
+ struct i2c_adapter *parent = muxc->parent;
+ int ret;
+
+ /* Switch to the right mux port and perform the transfer. */
+
+ ret = muxc->select(muxc, priv->chan_id);
+ if (ret >= 0)
+ ret = i2c_transfer(parent, msgs, num);
+ if (muxc->deselect)
+ muxc->deselect(muxc, priv->chan_id);
+
+ return ret;
+}
+
static int i2c_mux_smbus_xfer(struct i2c_adapter *adap,
u16 addr, unsigned short flags,
char read_write, u8 command,
@@ -76,6 +95,28 @@ static int i2c_mux_smbus_xfer(struct i2c_adapter *adap,
return ret;
}
+static int __i2c_mux_smbus_xfer(struct i2c_adapter *adap,
+ u16 addr, unsigned short flags,
+ char read_write, u8 command,
+ int size, union i2c_smbus_data *data)
+{
+ struct i2c_mux_priv *priv = adap->algo_data;
+ struct i2c_mux_core *muxc = priv->muxc;
+ struct i2c_adapter *parent = muxc->parent;
+ int ret;
+
+ /* Select the right mux port and perform the transfer. */
+
+ ret = muxc->select(muxc, 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);
+
+ return ret;
+}
+
/* Return the parent's functionality */
static u32 i2c_mux_functionality(struct i2c_adapter *adap)
{
@@ -98,6 +139,45 @@ static unsigned int i2c_mux_parent_classes(struct i2c_adapter *parent)
return class;
}
+static void i2c_mux_lock_bus(struct i2c_adapter *adapter, int flags)
+{
+ struct i2c_mux_priv *priv = adapter->algo_data;
+ struct i2c_mux_core *muxc = priv->muxc;
+ struct i2c_adapter *parent = muxc->parent;
+
+ rt_mutex_lock(&muxc->bus_lock);
+ if (!(flags & I2C_LOCK_ADAPTER))
+ return;
+ i2c_lock_bus(parent, flags);
+}
+
+static int i2c_mux_trylock_bus(struct i2c_adapter *adapter, int flags)
+{
+ struct i2c_mux_priv *priv = adapter->algo_data;
+ struct i2c_mux_core *muxc = priv->muxc;
+ struct i2c_adapter *parent = muxc->parent;
+
+ if (!rt_mutex_trylock(&muxc->bus_lock))
+ return 0;
+ if (!(flags & I2C_LOCK_ADAPTER))
+ return 1;
+ if (parent->trylock_bus(parent, flags))
+ return 1;
+ rt_mutex_unlock(&muxc->bus_lock);
+ return 0;
+}
+
+static void i2c_mux_unlock_bus(struct i2c_adapter *adapter, int flags)
+{
+ struct i2c_mux_priv *priv = adapter->algo_data;
+ struct i2c_mux_core *muxc = priv->muxc;
+ struct i2c_adapter *parent = muxc->parent;
+
+ if (flags & I2C_LOCK_ADAPTER)
+ i2c_unlock_bus(parent, flags);
+ rt_mutex_unlock(&muxc->bus_lock);
+}
+
static void i2c_parent_lock_bus(struct i2c_adapter *adapter, int flags)
{
struct i2c_mux_priv *priv = adapter->algo_data;
@@ -122,6 +202,31 @@ static void i2c_parent_unlock_bus(struct i2c_adapter *adapter, int flags)
parent->unlock_bus(parent, flags);
}
+struct i2c_adapter *i2c_root_adapter(struct device *dev)
+{
+ struct device *i2c;
+ struct i2c_adapter *i2c_root;
+
+ /*
+ * Walk up the device tree to find an i2c adapter, indicating
+ * that this is an i2c client device. Check all ancestors to
+ * handle mfd devices etc.
+ */
+ for (i2c = dev; i2c; i2c = i2c->parent) {
+ if (i2c->type == &i2c_adapter_type)
+ break;
+ }
+ if (!i2c)
+ return NULL;
+
+ /* Continue up the tree to find the root i2c adapter */
+ i2c_root = to_i2c_adapter(i2c);
+ while (i2c_parent_is_i2c_adapter(i2c_root))
+ i2c_root = i2c_parent_is_i2c_adapter(i2c_root);
+
+ return i2c_root;
+}
+
int i2c_mux_reserve_adapters(struct i2c_mux_core *muxc, int adapters)
{
struct i2c_adapter **adapter;
@@ -157,6 +262,7 @@ struct i2c_mux_core *i2c_mux_alloc(struct device *dev, int sizeof_priv)
if (sizeof_priv)
muxc->priv = muxc + 1;
muxc->dev = dev;
+ rt_mutex_init(&muxc->bus_lock);
return muxc;
}
EXPORT_SYMBOL_GPL(i2c_mux_alloc);
@@ -191,10 +297,18 @@ int i2c_add_mux_adapter(struct i2c_mux_core *muxc,
/* Need to do algo dynamically because we don't know ahead
* of time what sort of physical adapter we'll be dealing with.
*/
- if (parent->algo->master_xfer)
- priv->algo.master_xfer = i2c_mux_master_xfer;
- if (parent->algo->smbus_xfer)
- priv->algo.smbus_xfer = i2c_mux_smbus_xfer;
+ if (parent->algo->master_xfer) {
+ if (muxc->i2c_controlled)
+ priv->algo.master_xfer = __i2c_mux_master_xfer;
+ else
+ priv->algo.master_xfer = i2c_mux_master_xfer;
+ }
+ if (parent->algo->smbus_xfer) {
+ if (muxc->i2c_controlled)
+ priv->algo.smbus_xfer = __i2c_mux_smbus_xfer;
+ else
+ priv->algo.smbus_xfer = i2c_mux_smbus_xfer;
+ }
priv->algo.functionality = i2c_mux_functionality;
/* Now fill out new adapter structure */
@@ -207,9 +321,15 @@ int i2c_add_mux_adapter(struct i2c_mux_core *muxc,
priv->adap.retries = parent->retries;
priv->adap.timeout = parent->timeout;
priv->adap.quirks = parent->quirks;
- priv->adap.lock_bus = i2c_parent_lock_bus;
- priv->adap.trylock_bus = i2c_parent_trylock_bus;
- priv->adap.unlock_bus = i2c_parent_unlock_bus;
+ if (muxc->i2c_controlled) {
+ priv->adap.lock_bus = i2c_mux_lock_bus;
+ priv->adap.trylock_bus = i2c_mux_trylock_bus;
+ priv->adap.unlock_bus = i2c_mux_unlock_bus;
+ } else {
+ priv->adap.lock_bus = i2c_parent_lock_bus;
+ priv->adap.trylock_bus = i2c_parent_trylock_bus;
+ priv->adap.unlock_bus = i2c_parent_unlock_bus;
+ }
/* Sanity check on class */
if (i2c_mux_parent_classes(parent) & class)
diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
index e800c4597fa4..53b466e32651 100644
--- a/drivers/i2c/muxes/i2c-mux-gpio.c
+++ b/drivers/i2c/muxes/i2c-mux-gpio.c
@@ -15,6 +15,7 @@
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/gpio.h>
+#include "../../gpio/gpiolib.h"
#include <linux/of_gpio.h>
struct gpiomux {
@@ -137,6 +138,7 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
struct i2c_mux_core *muxc;
struct gpiomux *mux;
struct i2c_adapter *parent;
+ struct i2c_adapter *root;
unsigned initial_state, gpio_base;
int i, ret;
@@ -177,6 +179,9 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
if (!parent)
return -EPROBE_DEFER;
+ root = i2c_root_adapter(&parent->dev);
+
+ muxc->i2c_controlled = true;
muxc->parent = parent;
muxc->select = i2c_mux_gpio_select;
mux->gpio_base = gpio_base;
@@ -194,6 +199,9 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
}
for (i = 0; i < mux->data.n_gpios; i++) {
+ struct device *gpio_dev;
+ struct gpio_desc *gpio_desc;
+
ret = gpio_request(gpio_base + mux->data.gpios[i], "i2c-mux-gpio");
if (ret) {
dev_err(&pdev->dev, "Failed to request GPIO %d\n",
@@ -210,8 +218,19 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
i++; /* gpio_request above succeeded, so must free */
goto err_request_gpio;
}
+
+ if (!muxc->i2c_controlled)
+ continue;
+
+ gpio_desc = gpio_to_desc(gpio_base + mux->data.gpios[i]);
+ gpio_dev = gpio_desc->chip->dev;
+ muxc->i2c_controlled = i2c_root_adapter(gpio_dev) == root;
}
+ if (muxc->i2c_controlled)
+ dev_info(&pdev->dev,
+ "lock select-transfer-deselect individually\n");
+
for (i = 0; i < mux->data.n_values; i++) {
u32 nr = mux->data.base_nr ? (mux->data.base_nr + i) : 0;
unsigned int class = mux->data.classes ? mux->data.classes[i] : 0;
diff --git a/drivers/i2c/muxes/i2c-mux-pinctrl.c b/drivers/i2c/muxes/i2c-mux-pinctrl.c
index 38129850cbe4..c741183f699e 100644
--- a/drivers/i2c/muxes/i2c-mux-pinctrl.c
+++ b/drivers/i2c/muxes/i2c-mux-pinctrl.c
@@ -24,6 +24,7 @@
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/of.h>
+#include "../../pinctrl/core.h"
struct i2c_mux_pinctrl {
struct i2c_mux_pinctrl_platform_data *pdata;
@@ -120,10 +121,31 @@ static inline int i2c_mux_pinctrl_parse_dt(struct i2c_mux_pinctrl *mux,
}
#endif
+static struct i2c_adapter *i2c_mux_pinctrl_root_adapter(
+ struct pinctrl_state *state)
+{
+ struct i2c_adapter *root = NULL;
+ struct pinctrl_setting *setting;
+ struct i2c_adapter *pin_root;
+
+ list_for_each_entry(setting, &state->settings, node) {
+ pin_root = i2c_root_adapter(setting->pctldev->dev);
+ if (!pin_root)
+ return NULL;
+ if (!root)
+ root = pin_root;
+ else if (root != pin_root)
+ return NULL;
+ }
+
+ return root;
+}
+
static int i2c_mux_pinctrl_probe(struct platform_device *pdev)
{
struct i2c_mux_core *muxc;
struct i2c_mux_pinctrl *mux;
+ struct i2c_adapter *root;
int i, ret;
muxc = i2c_mux_alloc(&pdev->dev, sizeof(*mux));
@@ -201,6 +223,23 @@ static int i2c_mux_pinctrl_probe(struct platform_device *pdev)
goto err;
}
+ root = i2c_root_adapter(&muxc->parent->dev);
+
+ muxc->i2c_controlled = true;
+ for (i = 0; i < mux->pdata->bus_count; i++) {
+ if (root != i2c_mux_pinctrl_root_adapter(mux->states[i])) {
+ muxc->i2c_controlled = false;
+ break;
+ }
+ }
+ if (muxc->i2c_controlled && mux->pdata->pinctrl_state_idle
+ && root != i2c_mux_pinctrl_root_adapter(mux->state_idle))
+ muxc->i2c_controlled = false;
+
+ if (muxc->i2c_controlled)
+ dev_info(&pdev->dev,
+ "lock select-transfer-deselect individually\n");
+
for (i = 0; i < mux->pdata->bus_count; i++) {
u32 bus = mux->pdata->base_bus_num ?
(mux->pdata->base_bus_num + i) : 0;
diff --git a/include/linux/i2c-mux.h b/include/linux/i2c-mux.h
index d88e0a3b6768..a4a566cb77e8 100644
--- a/include/linux/i2c-mux.h
+++ b/include/linux/i2c-mux.h
@@ -33,6 +33,8 @@ struct i2c_mux_core {
int adapters;
int max_adapters;
struct device *dev;
+ struct rt_mutex bus_lock;
+ bool i2c_controlled;
void *priv;
@@ -47,6 +49,8 @@ static inline void *i2c_mux_priv(struct i2c_mux_core *muxc)
return muxc->priv;
}
+struct i2c_adapter *i2c_root_adapter(struct device *dev);
+
int i2c_mux_reserve_adapters(struct i2c_mux_core *muxc, int adapters);
/*
--
2.1.4
^ permalink raw reply related [flat|nested] 15+ messages in thread
* Re: [PATCH v3 0/8] i2c mux cleanup and locking update
2016-01-08 15:04 [PATCH v3 0/8] i2c mux cleanup and locking update Peter Rosin
` (7 preceding siblings ...)
2016-01-08 15:04 ` [PATCH v3 8/8] i2c-mux: relax locking of the top i2c adapter during i2c controlled muxing Peter Rosin
@ 2016-03-02 17:29 ` Wolfram Sang
2016-03-02 22:55 ` Peter Rosin
2016-03-05 17:48 ` Jonathan Cameron
8 siblings, 2 replies; 15+ messages in thread
From: Wolfram Sang @ 2016-03-02 17:29 UTC (permalink / raw)
To: Peter Rosin
Cc: Peter Rosin, Peter Korsgaard, Guenter Roeck, Jonathan Cameron,
Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald,
Antti Palosaari, Mauro Carvalho Chehab, Rob Herring, Frank Rowand,
Grant Likely, Srinivas Pandruvada, Adriana Reus,
Krzysztof Kozlowski, Hans Verkuil, Nicholas Mc Guire,
Olli Salonen, linux-i2c, linux-kernel, linux-iio, linux-media,
devicetree
[-- Attachment #1: Type: text/plain, Size: 4719 bytes --]
On Fri, Jan 08, 2016 at 04:04:48PM +0100, Peter Rosin wrote:
> From: Peter Rosin <peda@axentia.se>
>
> Hi!
>
> [doing a v3 even if there is no "big picture" feedback yet, but
> previous versions has bugs that make them harder to test than
> needed, and testing is very much desired]
>
> I have a pair of boards with this i2c topology:
>
> GPIO ---| ------ BAT1
> | v /
> I2C -----+------B---+---- MUX
> | \
> EEPROM ------ BAT2
>
> (B denotes the boundary between the boards)
>
> The problem with this is that the GPIO controller sits on the same i2c bus
> that it MUXes. For pca954x devices this is worked around by using unlocked
> transfers when updating the MUX. I have no such luck as the GPIO is a general
> purpose IO expander and the MUX is just a random bidirectional MUX, unaware
> of the fact that it is muxing an i2c bus, and extending unlocked transfers
> into the GPIO subsystem is too ugly to even think about. But the general hw
> approach is sane in my opinion, with the number of connections between the
> two boards minimized. To put is plainly, I need support for it.
>
> So, I observe that while it is needed to have the i2c bus locked during the
> actual MUX update in order to avoid random garbage on the slave side, it
> is not strictly a must to have it locked over the whole sequence of a full
> select-transfer-deselect operation. The MUX itself needs to be locked, so
> transfers to clients behind the mux are serialized, and the MUX needs to be
> stable during all i2c traffic (otherwise individual mux slave segments
> might see garbage).
>
> This series accomplishes this by adding code to i2c-mux-gpio and
> i2c-mux-pinctrl that determines if all involved devices used to update the
> mux are controlled by the same root i2c adapter that is muxed. When this
> is the case, the select-transfer-deselect operations should be locked
> individually to avoid the deadlock. The i2c bus *is* still locked
> during muxing, since the muxing happens as part of i2c transfers. This
> is true even if the MUX is updated with several transfers to the GPIO (at
> least as long as *all* MUX changes are using the i2s master bus). A lock
> is added to the mux so that transfers through the mux are serialized.
>
> Concerns:
> - The locking is perhaps too complex?
> - I worry about the priority inheritance aspect of the adapter lock. When
> the transfers behind the mux are divided into select-transfer-deselect all
> locked individually, low priority transfers get more chances to interfere
> with high priority transfers.
> - When doing an i2c_transfer() in_atomic() context or with irqs_disabled(),
> there is a higher possibility that the mux is not returned to its idle
> state after a failed (-EAGAIN) transfer due to trylock.
> - Is the detection of i2c-controlled gpios and pinctrls sane (i.e. the
> usage of the new i2c_root_adapter() function in 8/8)?
>
> To summarize the series, there's some i2c-mux infrastructure cleanup work
> first (I think that part stands by itself as desireable regardless), the
> locking changes are in the last three patches of the series, with the real
> meat in 8/8.
>
> PS. needs a bunch of testing, I do not have access to all the involved hw
I want to let you know that I am currently thinking about this series.
There seems to be a second occasion where it could have helped AFAICT.
http://patchwork.ozlabs.org/patch/584776/ (check my comments there from
yesterday and today)
First of all, really thank you that you tried to find the proper
solution and went all the way for it. It is easy to do a fire&forget
hack here, but you didn't.
I hope you understand, though, that I need to make a balance between
features and complexity in my subsystem to have maintainable and stable
code.
As I wrote in the mentioned thread already: "However, I am still
undecided if that series should go upstream because it makes the mux
code another magnitude more complex. And while this seems to be the
second issue which could be fixed by that series, both issues seem to
be corner cases, so I am not sure it is worth the complexity."
And for the cleanup series using struct mux_core. It is quite an
intrusive change and, frankly, the savings look surprisingly low. I
would have expected more, but you never find out until you do it. So, I
am unsure here as well.
I am not decided and open for discussion. This is just where we are
currently. All interested parties, I am looking forward to more
thoughts.
Thanks,
Wolfram
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 819 bytes --]
^ permalink raw reply [flat|nested] 15+ messages in thread
* RE: [PATCH v3 0/8] i2c mux cleanup and locking update
2016-03-02 17:29 ` [PATCH v3 0/8] i2c mux cleanup and locking update Wolfram Sang
@ 2016-03-02 22:55 ` Peter Rosin
2016-03-05 17:48 ` Jonathan Cameron
1 sibling, 0 replies; 15+ messages in thread
From: Peter Rosin @ 2016-03-02 22:55 UTC (permalink / raw)
To: Wolfram Sang, Peter Rosin
Cc: Peter Korsgaard, Guenter Roeck, Jonathan Cameron, Hartmut Knaack,
Lars-Peter Clausen, Peter Meerwald, Antti Palosaari,
Mauro Carvalho Chehab, Rob Herring, Frank Rowand, Grant Likely,
Srinivas Pandruvada, Adriana Reus, Krzysztof Kozlowski,
Hans Verkuil, Nicholas Mc Guire, Olli Salonen,
linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
linux-iio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-media
Wolfram Sang wrote:
> On Fri, Jan 08, 2016 at 04:04:48PM +0100, Peter Rosin wrote:
> >
> > Hi!
> >
> > [doing a v3 even if there is no "big picture" feedback yet, but
> > previous versions has bugs that make them harder to test than
> > needed, and testing is very much desired]
> >
> > I have a pair of boards with this i2c topology:
> >
> > GPIO ---| ------ BAT1
> > | v /
> > I2C -----+------B---+---- MUX
> > | \
> > EEPROM ------ BAT2
> >
> > (B denotes the boundary between the boards)
> >
> > The problem with this is that the GPIO controller sits on the same i2c bus
> > that it MUXes. For pca954x devices this is worked around by using unlocked
> > transfers when updating the MUX. I have no such luck as the GPIO is a general
> > purpose IO expander and the MUX is just a random bidirectional MUX, unaware
> > of the fact that it is muxing an i2c bus, and extending unlocked transfers
> > into the GPIO subsystem is too ugly to even think about. But the general hw
> > approach is sane in my opinion, with the number of connections between the
> > two boards minimized. To put is plainly, I need support for it.
> >
> > So, I observe that while it is needed to have the i2c bus locked during the
> > actual MUX update in order to avoid random garbage on the slave side, it
> > is not strictly a must to have it locked over the whole sequence of a full
> > select-transfer-deselect operation. The MUX itself needs to be locked, so
> > transfers to clients behind the mux are serialized, and the MUX needs to be
> > stable during all i2c traffic (otherwise individual mux slave segments
> > might see garbage).
> >
> > This series accomplishes this by adding code to i2c-mux-gpio and
> > i2c-mux-pinctrl that determines if all involved devices used to update the
> > mux are controlled by the same root i2c adapter that is muxed. When this
> > is the case, the select-transfer-deselect operations should be locked
> > individually to avoid the deadlock. The i2c bus *is* still locked
> > during muxing, since the muxing happens as part of i2c transfers. This
> > is true even if the MUX is updated with several transfers to the GPIO (at
> > least as long as *all* MUX changes are using the i2s master bus). A lock
> > is added to the mux so that transfers through the mux are serialized.
> >
> > Concerns:
> > - The locking is perhaps too complex?
> > - I worry about the priority inheritance aspect of the adapter lock. When
> > the transfers behind the mux are divided into select-transfer-deselect all
> > locked individually, low priority transfers get more chances to interfere
> > with high priority transfers.
> > - When doing an i2c_transfer() in_atomic() context or with irqs_disabled(),
> > there is a higher possibility that the mux is not returned to its idle
> > state after a failed (-EAGAIN) transfer due to trylock.
> > - Is the detection of i2c-controlled gpios and pinctrls sane (i.e. the
> > usage of the new i2c_root_adapter() function in 8/8)?
> >
> > To summarize the series, there's some i2c-mux infrastructure cleanup work
> > first (I think that part stands by itself as desireable regardless), the
> > locking changes are in the last three patches of the series, with the real
> > meat in 8/8.
> >
> > PS. needs a bunch of testing, I do not have access to all the involved hw
>
> I want to let you know that I am currently thinking about this series.
Glad to hear it!
> There seems to be a second occasion where it could have helped AFAICT.
> http://patchwork.ozlabs.org/patch/584776/ (check my comments there from
> yesterday and today)
The mpu6050 driver has to set muxc->i2c_controlled before adding
any child adapters for anything to behave differently, and it also
has to make sure that all accesses in select/deselect are normal
i2c accesses (i.e. not unlocked accesses). When doing so,
unreleated i2c traffic might interleave with the muxing. So, if
the chip is auto-deselecting on the first i2c transfer after select
it will never work properly.
> First of all, really thank you that you tried to find the proper
> solution and went all the way for it. It is easy to do a fire&forget
> hack here, but you didn't.
Fire&forget often turns out to be just the fire. If you do it properly
there is a better chance that you really can forget it...
> I hope you understand, though, that I need to make a balance between
> features and complexity in my subsystem to have maintainable and stable
> code.
>
> As I wrote in the mentioned thread already: "However, I am still
> undecided if that series should go upstream because it makes the mux
> code another magnitude more complex. And while this seems to be the
> second issue which could be fixed by that series, both issues seem to
> be corner cases, so I am not sure it is worth the complexity."
>
> And for the cleanup series using struct mux_core. It is quite an
> intrusive change and, frankly, the savings look surprisingly low. I
> would have expected more, but you never find out until you do it. So, I
> am unsure here as well.
Yes, that part of the series went ballistic when the half-dozen mux
users outside of drivers/i2c was added to the mix (I was originally
not aware of them). The savings looked better when only the i2c-internal
muxes was considered, mainly because the external muxes are often not
real muxes and only have one child adapter. Creating the mux-core for
that one adapter then swallows the savings.
Funnily enough, I was just the other day looking at the series again and
decided to redo those 5 patches so that I first add the new mux core
and implement the old interface in terms of the new interface, then
convert all the mux users one patch at a time, then remove the glue.
That means 15 patches instead of 5, but each patch only touches one
subsystem, which should ease the transition. The end result is
equivalent, I only had to change a few names to make it possible to
have both the old and the new interfaces active at the same time.
In doing so, I realized that what might be good for the non-generic
one-child-only "muxes" is perhaps an interface that creates a mux core
and registers one child adapter with one call?
One other thing that could help the +- statistics is to maybe add more
parameters to i2c_mux_alloc, such as parent adapter and select/deselect
ops. But that is fairly cosmetic...
> I am not decided and open for discussion. This is just where we are
> currently. All interested parties, I am looking forward to more
> thoughts.
Cheers,
Peter
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v3 0/8] i2c mux cleanup and locking update
2016-03-02 17:29 ` [PATCH v3 0/8] i2c mux cleanup and locking update Wolfram Sang
2016-03-02 22:55 ` Peter Rosin
@ 2016-03-05 17:48 ` Jonathan Cameron
[not found] ` <56DB1C07.4040008-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
1 sibling, 1 reply; 15+ messages in thread
From: Jonathan Cameron @ 2016-03-05 17:48 UTC (permalink / raw)
To: Wolfram Sang, Peter Rosin
Cc: Peter Rosin, Peter Korsgaard, Guenter Roeck, Hartmut Knaack,
Lars-Peter Clausen, Peter Meerwald, Antti Palosaari,
Mauro Carvalho Chehab, Rob Herring, Frank Rowand, Grant Likely,
Srinivas Pandruvada, Adriana Reus, Krzysztof Kozlowski,
Hans Verkuil, Nicholas Mc Guire, Olli Salonen,
linux-i2c-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA,
linux-iio-u79uwXL29TY76Z2rM5mHXA,
linux-media-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA
On 02/03/16 17:29, Wolfram Sang wrote:
> On Fri, Jan 08, 2016 at 04:04:48PM +0100, Peter Rosin wrote:
>> From: Peter Rosin <peda-koto5C5qi+TLoDKTGw+V6w@public.gmane.org>
>>
>> Hi!
>>
>> [doing a v3 even if there is no "big picture" feedback yet, but
>> previous versions has bugs that make them harder to test than
>> needed, and testing is very much desired]
>>
>> I have a pair of boards with this i2c topology:
>>
>> GPIO ---| ------ BAT1
>> | v /
>> I2C -----+------B---+---- MUX
>> | \
>> EEPROM ------ BAT2
>>
>> (B denotes the boundary between the boards)
>>
>> The problem with this is that the GPIO controller sits on the same i2c bus
>> that it MUXes. For pca954x devices this is worked around by using unlocked
>> transfers when updating the MUX. I have no such luck as the GPIO is a general
>> purpose IO expander and the MUX is just a random bidirectional MUX, unaware
>> of the fact that it is muxing an i2c bus, and extending unlocked transfers
>> into the GPIO subsystem is too ugly to even think about. But the general hw
>> approach is sane in my opinion, with the number of connections between the
>> two boards minimized. To put is plainly, I need support for it.
>>
>> So, I observe that while it is needed to have the i2c bus locked during the
>> actual MUX update in order to avoid random garbage on the slave side, it
>> is not strictly a must to have it locked over the whole sequence of a full
>> select-transfer-deselect operation. The MUX itself needs to be locked, so
>> transfers to clients behind the mux are serialized, and the MUX needs to be
>> stable during all i2c traffic (otherwise individual mux slave segments
>> might see garbage).
>>
>> This series accomplishes this by adding code to i2c-mux-gpio and
>> i2c-mux-pinctrl that determines if all involved devices used to update the
>> mux are controlled by the same root i2c adapter that is muxed. When this
>> is the case, the select-transfer-deselect operations should be locked
>> individually to avoid the deadlock. The i2c bus *is* still locked
>> during muxing, since the muxing happens as part of i2c transfers. This
>> is true even if the MUX is updated with several transfers to the GPIO (at
>> least as long as *all* MUX changes are using the i2s master bus). A lock
>> is added to the mux so that transfers through the mux are serialized.
>>
>> Concerns:
>> - The locking is perhaps too complex?
>> - I worry about the priority inheritance aspect of the adapter lock. When
>> the transfers behind the mux are divided into select-transfer-deselect all
>> locked individually, low priority transfers get more chances to interfere
>> with high priority transfers.
>> - When doing an i2c_transfer() in_atomic() context or with irqs_disabled(),
>> there is a higher possibility that the mux is not returned to its idle
>> state after a failed (-EAGAIN) transfer due to trylock.
>> - Is the detection of i2c-controlled gpios and pinctrls sane (i.e. the
>> usage of the new i2c_root_adapter() function in 8/8)?
>>
>> To summarize the series, there's some i2c-mux infrastructure cleanup work
>> first (I think that part stands by itself as desireable regardless), the
>> locking changes are in the last three patches of the series, with the real
>> meat in 8/8.
>>
>> PS. needs a bunch of testing, I do not have access to all the involved hw
>
> I want to let you know that I am currently thinking about this series.
>
> There seems to be a second occasion where it could have helped AFAICT.
> http://patchwork.ozlabs.org/patch/584776/ (check my comments there from
> yesterday and today)
>
> First of all, really thank you that you tried to find the proper
> solution and went all the way for it. It is easy to do a fire&forget
> hack here, but you didn't.
>
> I hope you understand, though, that I need to make a balance between
> features and complexity in my subsystem to have maintainable and stable
> code.
>
> As I wrote in the mentioned thread already: "However, I am still
> undecided if that series should go upstream because it makes the mux
> code another magnitude more complex. And while this seems to be the
> second issue which could be fixed by that series, both issues seem to
> be corner cases, so I am not sure it is worth the complexity."
>
> And for the cleanup series using struct mux_core. It is quite an
> intrusive change and, frankly, the savings look surprisingly low. I
> would have expected more, but you never find out until you do it. So, I
> am unsure here as well.
>
> I am not decided and open for discussion. This is just where we are
> currently. All interested parties, I am looking forward to more
> thoughts.
>
> Thanks,
Perhaps it's one to let sit into at least the next cycle (and get some testing
on those media devices if we can) but, whilst it is fiddly the gains seen in
individual drivers (like the example Peter put in response to the V4 series)
make it look worthwhile to me. Also, whilst the invensense part is plain odd
in many ways, the case Peter had looks rather more normal.
At the end of the day, sometimes fiddly problems need fiddly code.
(says a guy who doesn't have to maintain it!)
It certainly helps that Peter has done a thorough job, broken the patches
up cleanly and provided clean descriptions of what he is doing.
Jonathan
>
> Wolfram
>
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v3 0/8] i2c mux cleanup and locking update
[not found] ` <56DB1C07.4040008-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
@ 2016-03-05 18:29 ` Wolfram Sang
2016-03-07 8:38 ` Peter Rosin
0 siblings, 1 reply; 15+ messages in thread
From: Wolfram Sang @ 2016-03-05 18:29 UTC (permalink / raw)
To: Jonathan Cameron
Cc: Peter Rosin, Peter Rosin, Peter Korsgaard, Guenter Roeck,
Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald,
Antti Palosaari, Mauro Carvalho Chehab, Rob Herring, Frank Rowand,
Grant Likely, Srinivas Pandruvada, Adriana Reus,
Krzysztof Kozlowski, Hans Verkuil, Nicholas Mc Guire,
Olli Salonen, linux-i2c-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA,
linux-iio-u79uwXL29TY76Z2rM5mHXA,
linux-media-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA
[-- Attachment #1: Type: text/plain, Size: 1689 bytes --]
> Perhaps it's one to let sit into at least the next cycle (and get some testing
> on those media devices if we can) but, whilst it is fiddly the gains seen in
> individual drivers (like the example Peter put in response to the V4 series)
> make it look worthwhile to me. Also, whilst the invensense part is plain odd
> in many ways, the case Peter had looks rather more normal.
>
> At the end of the day, sometimes fiddly problems need fiddly code.
> (says a guy who doesn't have to maintain it!)
>
> It certainly helps that Peter has done a thorough job, broken the patches
> up cleanly and provided clean descriptions of what he is doing.
Yes, Peter has done a great job so far and the latest results were very
convincing (fixing the invensense issue and the savings for rtl2832).
And yes, I am reluctant to maintain this code alone, so my question
would be:
Peter, are you interested in becoming the i2c-mux maintainer and look
after the code even after it was merged? (From "you reviewing patches and
me picking them up" to "you have your own branch which I pull", we can
discuss the best workflow.)
If that would be the case, I have the same idea like Jonathan: Give it
another cycle for more review & test and aim for the 4.7 merge window.
I have to admit that I still haven't done a more thorough review, so I
can't say if I see a show-stopper in this series. Yet, even if so I am
positive it can be sorted out. Oh, and we should call for people with
special experience in locking.
What do people think?
Regards,
Wolfram
PS: Peter, have you seen my demuxer driver in my for-next branch? I hope
it won't spoil your design?
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^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v3 0/8] i2c mux cleanup and locking update
2016-03-05 18:29 ` Wolfram Sang
@ 2016-03-07 8:38 ` Peter Rosin
2016-03-07 10:23 ` Wolfram Sang
0 siblings, 1 reply; 15+ messages in thread
From: Peter Rosin @ 2016-03-07 8:38 UTC (permalink / raw)
To: Wolfram Sang, Jonathan Cameron
Cc: Peter Rosin, Peter Korsgaard, Guenter Roeck, Hartmut Knaack,
Lars-Peter Clausen, Peter Meerwald, Antti Palosaari,
Mauro Carvalho Chehab, Rob Herring, Frank Rowand, Grant Likely,
Srinivas Pandruvada, Adriana Reus, Krzysztof Kozlowski,
Hans Verkuil, Nicholas Mc Guire, Olli Salonen, linux-i2c,
linux-kernel, linux-iio, linux-media, devicetree
On 2016-03-05 19:29, Wolfram Sang wrote:
>
>> Perhaps it's one to let sit into at least the next cycle (and get some testing
>> on those media devices if we can) but, whilst it is fiddly the gains seen in
>> individual drivers (like the example Peter put in response to the V4 series)
>> make it look worthwhile to me. Also, whilst the invensense part is plain odd
>> in many ways, the case Peter had looks rather more normal.
>>
>> At the end of the day, sometimes fiddly problems need fiddly code.
>> (says a guy who doesn't have to maintain it!)
>>
>> It certainly helps that Peter has done a thorough job, broken the patches
>> up cleanly and provided clean descriptions of what he is doing.
>
> Yes, Peter has done a great job so far and the latest results were very
> convincing (fixing the invensense issue and the savings for rtl2832).
>
> And yes, I am reluctant to maintain this code alone, so my question
> would be:
>
> Peter, are you interested in becoming the i2c-mux maintainer and look
> after the code even after it was merged? (From "you reviewing patches and
> me picking them up" to "you have your own branch which I pull", we can
> discuss the best workflow.)
My code wouldn't be worth much if I didn't offer to look after it myself. On
the other hand, I am also reluctant to be the go-to person for all things
i2c-mux, as I don't have a clear picture of how much work it's going to be.
My offer is going to be this, I'll look after any unforeseen future problems
caused by this rework, and I can be the i2c-mux maintainer. But if being
the i2c-mux maintainer turns out to be a huge time-sink, there is no way I
can stay on in the long run. But I guess that is the same for any maintainer
(whose job description does not explicitly include being maintainer).
> If that would be the case, I have the same idea like Jonathan: Give it
> another cycle for more review & test and aim for the 4.7 merge window.
Yes, sounds good. One of the reasons for doing things right (or at least
trying to) is to have more people look at the work. *I* think it's good,
but more eyes can't hurt.
> I have to admit that I still haven't done a more thorough review, so I
> can't say if I see a show-stopper in this series. Yet, even if so I am
> positive it can be sorted out. Oh, and we should call for people with
> special experience in locking.
>
> What do people think?
>
> Regards,
>
> Wolfram
>
> PS: Peter, have you seen my demuxer driver in my for-next branch? I hope
> it won't spoil your design?
I had a brief look, and I can't see anything in the demux that's affected by
the mux update. The main commonality of the demux and the preexisting muxes
seems to be that the name includes "mux" and that it is all about i2c. Agreed?
In short, I see no problems.
Cheers,
Peter
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v3 0/8] i2c mux cleanup and locking update
2016-03-07 8:38 ` Peter Rosin
@ 2016-03-07 10:23 ` Wolfram Sang
0 siblings, 0 replies; 15+ messages in thread
From: Wolfram Sang @ 2016-03-07 10:23 UTC (permalink / raw)
To: Peter Rosin
Cc: Jonathan Cameron, Peter Rosin, Peter Korsgaard, Guenter Roeck,
Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald,
Antti Palosaari, Mauro Carvalho Chehab, Rob Herring, Frank Rowand,
Grant Likely, Srinivas Pandruvada, Adriana Reus,
Krzysztof Kozlowski, Hans Verkuil, Nicholas Mc Guire,
Olli Salonen, linux-i2c, linux-kernel, linux-iio, linux-media,
devicetree
[-- Attachment #1: Type: text/plain, Size: 1248 bytes --]
> My offer is going to be this, I'll look after any unforeseen future problems
> caused by this rework, and I can be the i2c-mux maintainer. But if being
Yay, thanks a lot!
> the i2c-mux maintainer turns out to be a huge time-sink, there is no way I
> can stay on in the long run. But I guess that is the same for any maintainer
> (whose job description does not explicitly include being maintainer).
Well, since I became the I2C maintainer in late 2012, i2c-mux was always
low-bandwidth:
$ git log --pretty=oneline v3.2.. -- drivers/i2c/muxes/ drivers/i2c/i2c-mux.c | wc -l
72
And your patch series is already bigger than what was accepted in the
last year altogether :) I understand the uncertainty feeling about this
step; however, I truly think it is not much work. It is a niche -
though, one I'd like to have supported by your expertise.
> the mux update. The main commonality of the demux and the preexisting muxes
> seems to be that the name includes "mux" and that it is all about i2c. Agreed?
Yes, and because they are quite different, I wasn't sure if it a) is not
affected at all or b) totally breaks the design. Glad to hear it is a).
Thanks again, looks like we have a roadmap now for getting this series
in \o/
Wolfram
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^ permalink raw reply [flat|nested] 15+ messages in thread
end of thread, other threads:[~2016-03-07 10:23 UTC | newest]
Thread overview: 15+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2016-01-08 15:04 [PATCH v3 0/8] i2c mux cleanup and locking update Peter Rosin
[not found] ` <1452265496-22475-1-git-send-email-peda-SamgB31n2u5IcsJQ0EH25Q@public.gmane.org>
2016-01-08 15:04 ` [PATCH v3 1/8] i2c-mux: add common core data for every mux instance Peter Rosin
2016-01-08 15:04 ` [PATCH v3 2/8] i2c-mux: move select and deselect ops to i2c_mux_core Peter Rosin
2016-01-08 15:04 ` [PATCH v3 3/8] i2c-mux: move the slave side adapter management " Peter Rosin
2016-01-08 15:04 ` [PATCH v3 4/8] i2c-mux: remove the mux dev pointer from the mux per channel data Peter Rosin
2016-01-08 15:04 ` [PATCH v3 5/8] i2c-mux: pinctrl: get rid of the driver private struct device pointer Peter Rosin
2016-01-08 15:04 ` [PATCH v3 6/8] i2c: allow adapter drivers to override the adapter locking Peter Rosin
2016-01-08 15:04 ` [PATCH v3 7/8] i2c: muxes always lock the parent adapter Peter Rosin
2016-01-08 15:04 ` [PATCH v3 8/8] i2c-mux: relax locking of the top i2c adapter during i2c controlled muxing Peter Rosin
2016-03-02 17:29 ` [PATCH v3 0/8] i2c mux cleanup and locking update Wolfram Sang
2016-03-02 22:55 ` Peter Rosin
2016-03-05 17:48 ` Jonathan Cameron
[not found] ` <56DB1C07.4040008-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
2016-03-05 18:29 ` Wolfram Sang
2016-03-07 8:38 ` Peter Rosin
2016-03-07 10:23 ` Wolfram Sang
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