* [RFC PATCH 1/2] i2c: Add a struct device * parameter to i2c_add_mux_adapter()
2011-08-25 0:25 [RFC PATCH 0/2] i2c/of: Populate multiplexed i2c busses from the device tree David Daney
@ 2011-08-25 0:25 ` David Daney
2011-08-25 0:25 ` [RFC PATCH 2/2] i2c/of: Automatically populate i2c mux busses from device tree data David Daney
1 sibling, 0 replies; 3+ messages in thread
From: David Daney @ 2011-08-25 0:25 UTC (permalink / raw)
To: devicetree-discuss, grant.likely, linux-kernel; +Cc: David Daney
And adjust all callers.
The new device parameter is used in the next patch to initialize the
mux's of_node so that its children may be automatically populated.
Signed-off-by: David Daney <david.daney@cavium.com>
---
drivers/i2c/i2c-mux.c | 19 ++++++++++---------
drivers/i2c/muxes/gpio-i2cmux.c | 3 ++-
drivers/i2c/muxes/pca9541.c | 3 ++-
drivers/i2c/muxes/pca954x.c | 2 +-
include/linux/i2c-mux.h | 3 ++-
5 files changed, 17 insertions(+), 13 deletions(-)
diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c
index d32a484..6fc2dd4 100644
--- a/drivers/i2c/i2c-mux.c
+++ b/drivers/i2c/i2c-mux.c
@@ -31,11 +31,11 @@ struct i2c_mux_priv {
struct i2c_algorithm algo;
struct i2c_adapter *parent;
- void *mux_dev; /* the mux chip/device */
+ void *mux_priv; /* the mux chip/device */
u32 chan_id; /* the channel id */
- int (*select)(struct i2c_adapter *, void *mux_dev, u32 chan_id);
- int (*deselect)(struct i2c_adapter *, void *mux_dev, 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,
@@ -47,11 +47,11 @@ 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_dev, priv->chan_id);
+ ret = priv->select(parent, priv->mux_priv, priv->chan_id);
if (ret >= 0)
ret = parent->algo->master_xfer(parent, msgs, num);
if (priv->deselect)
- priv->deselect(parent, priv->mux_dev, priv->chan_id);
+ priv->deselect(parent, priv->mux_priv, priv->chan_id);
return ret;
}
@@ -67,12 +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_dev, priv->chan_id);
+ ret = priv->select(parent, priv->mux_priv, 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_dev, priv->chan_id);
+ priv->deselect(parent, priv->mux_priv, priv->chan_id);
return ret;
}
@@ -87,7 +87,8 @@ static u32 i2c_mux_functionality(struct i2c_adapter *adap)
}
struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
- void *mux_dev, u32 force_nr, u32 chan_id,
+ struct device *mux_dev,
+ void *mux_priv, u32 force_nr, u32 chan_id,
int (*select) (struct i2c_adapter *,
void *, u32),
int (*deselect) (struct i2c_adapter *,
@@ -102,7 +103,7 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
/* Set up private adapter data */
priv->parent = parent;
- priv->mux_dev = mux_dev;
+ priv->mux_priv = mux_priv;
priv->chan_id = chan_id;
priv->select = select;
priv->deselect = deselect;
diff --git a/drivers/i2c/muxes/gpio-i2cmux.c b/drivers/i2c/muxes/gpio-i2cmux.c
index 7b6ce62..cd238c7 100644
--- a/drivers/i2c/muxes/gpio-i2cmux.c
+++ b/drivers/i2c/muxes/gpio-i2cmux.c
@@ -105,7 +105,8 @@ static int __devinit gpiomux_probe(struct platform_device *pdev)
for (i = 0; i < pdata->n_values; i++) {
u32 nr = pdata->base_nr ? (pdata->base_nr + i) : 0;
- mux->adap[i] = i2c_add_mux_adapter(parent, mux, nr, i,
+ mux->adap[i] = i2c_add_mux_adapter(parent, &pdev->dev, mux,
+ nr, i,
gpiomux_select, deselect);
if (!mux->adap[i]) {
ret = -ENODEV;
diff --git a/drivers/i2c/muxes/pca9541.c b/drivers/i2c/muxes/pca9541.c
index ed699c5..e9e07ba 100644
--- a/drivers/i2c/muxes/pca9541.c
+++ b/drivers/i2c/muxes/pca9541.c
@@ -353,7 +353,8 @@ 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, force, 0,
+ data->mux_adap = i2c_add_mux_adapter(adap, &client->dev, client,
+ force, 0,
pca9541_select_chan,
pca9541_release_chan);
diff --git a/drivers/i2c/muxes/pca954x.c b/drivers/i2c/muxes/pca954x.c
index 6f89536..5c6ecc7 100644
--- a/drivers/i2c/muxes/pca954x.c
+++ b/drivers/i2c/muxes/pca954x.c
@@ -226,7 +226,7 @@ static int pca954x_probe(struct i2c_client *client,
}
data->virt_adaps[num] =
- i2c_add_mux_adapter(adap, client,
+ i2c_add_mux_adapter(adap, &client->dev, client,
force, num, pca954x_select_chan,
(pdata && pdata->modes[num].deselect_on_exit)
? pca954x_deselect_mux : NULL);
diff --git a/include/linux/i2c-mux.h b/include/linux/i2c-mux.h
index 34536ef..260ca6a 100644
--- a/include/linux/i2c-mux.h
+++ b/include/linux/i2c-mux.h
@@ -33,7 +33,8 @@
* mux control.
*/
struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
- void *mux_dev, u32 force_nr, u32 chan_id,
+ struct device *mux_dev,
+ void *mux_priv, u32 force_nr, u32 chan_id,
int (*select) (struct i2c_adapter *,
void *mux_dev, u32 chan_id),
int (*deselect) (struct i2c_adapter *,
--
1.7.2.3
^ permalink raw reply related [flat|nested] 3+ messages in thread* [RFC PATCH 2/2] i2c/of: Automatically populate i2c mux busses from device tree data.
2011-08-25 0:25 [RFC PATCH 0/2] i2c/of: Populate multiplexed i2c busses from the device tree David Daney
2011-08-25 0:25 ` [RFC PATCH 1/2] i2c: Add a struct device * parameter to i2c_add_mux_adapter() David Daney
@ 2011-08-25 0:25 ` David Daney
1 sibling, 0 replies; 3+ messages in thread
From: David Daney @ 2011-08-25 0:25 UTC (permalink / raw)
To: devicetree-discuss, grant.likely, linux-kernel; +Cc: David Daney
For 'normal' i2c bus drivers, we can call of_i2c_register_devices()
and have the device tree framework automatically populate the bus with
the devices specified in the device tree.
This patch adds a common code to the i2c mux framework to hate the mux
sub-busses be populated by the of_i2c_register_devices() too. If the
mux device has an of_node, we populate the sub-bus' of_node so that
the subsequent call to of_i2c_register_devices() will find the
corresponding devices.
It seemed better to put this logic in i2c_add_mux_adapter() rather
than the individual mux drivers, as they will all probably want to do
the same thing.
Signed-off-by: David Daney <david.daney@cavium.com>
---
Documentation/devicetree/bindings/i2c/mux.txt | 54 +++++++++++++++++++++++++
drivers/i2c/i2c-mux.c | 25 +++++++++++
2 files changed, 79 insertions(+), 0 deletions(-)
create mode 100644 Documentation/devicetree/bindings/i2c/mux.txt
diff --git a/Documentation/devicetree/bindings/i2c/mux.txt b/Documentation/devicetree/bindings/i2c/mux.txt
new file mode 100644
index 0000000..7bd9192
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/mux.txt
@@ -0,0 +1,54 @@
+Common i2c bus multiplexer/switch properties.
+
+An i2c bus multiplexer/switch will have several child busses that are
+numbered uniquely in a device dependent manner. The nodes for an i2c bus
+multiplexer/switch will have one child node for each child
+bus.
+
+Required properties for child nodes:
+- #address-cells = <1>;
+- #size-cells = <0>;
+- cell-index : The sub-bus number.
+
+Optional properties for child nodes:
+- Other properties specific to the multiplexer/switch hardware.
+- Child nodes conforming to i2c bus binding
+
+
+Example :
+
+ /*
+ An NXP pca9548 8 channel I2C multiplexer at address 0x70
+ with two NXP pca8574 GPIO expanders attached, one each to
+ ports 3 and 4.
+ */
+
+ mux@70 {
+ compatible = "nxp,pca9548";
+ reg = <0x70>;
+
+ i2c@3 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ cell-index = <3>;
+
+ gpio1: gpio@38 {
+ compatible = "nxp,pca8574";
+ reg = <0x38>;
+ #gpio-cells = <2>;
+ gpio-controller;
+ };
+ };
+ i2c@4 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ cell-index = <4>;
+
+ gpio2: gpio@38 {
+ compatible = "nxp,pca8574";
+ reg = <0x38>;
+ #gpio-cells = <2>;
+ gpio-controller;
+ };
+ };
+ };
diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c
index 6fc2dd4..63f8989 100644
--- a/drivers/i2c/i2c-mux.c
+++ b/drivers/i2c/i2c-mux.c
@@ -24,6 +24,8 @@
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/i2c-mux.h>
+#include <linux/of.h>
+#include <linux/of_i2c.h>
/* multiplexer per channel data */
struct i2c_mux_priv {
@@ -143,6 +145,29 @@ struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
dev_info(&parent->dev, "Added multiplexed i2c bus %d\n",
i2c_adapter_id(&priv->adap));
+#ifdef CONFIG_OF
+ /* Try to get populate the mux adapter's of_node */
+ if (mux_dev->of_node) {
+ struct device_node *child = NULL;
+ const __be32 *cell_index;
+ int len;
+
+ for (;;) {
+ child = of_get_next_child(mux_dev->of_node, child);
+ if (!child)
+ break;
+ cell_index = of_get_property(child, "cell-index", &len);
+ if (!cell_index || (len < sizeof(__be32)))
+ continue;
+ if (chan_id == be32_to_cpup(cell_index)) {
+ priv->adap.dev.of_node = child;
+ break;
+ }
+ }
+ }
+ of_i2c_register_devices(&priv->adap);
+#endif
+
return &priv->adap;
}
EXPORT_SYMBOL_GPL(i2c_add_mux_adapter);
--
1.7.2.3
^ permalink raw reply related [flat|nested] 3+ messages in thread