v7:
- Reworked the commit message, comments and renamed a struct
field. No functional change.
v6:
- Fix typo in dt-bindings
v5:
- Remove optional and make vdd-supply mandatory
v4:
- Add missing maxitems dt-bindings property
v3:
- Merge dt-bindings into i2c-mux-pca954x.yaml
v2:
- Move dt-bindings to separate file
- Added support for MAX736x as they are very similar
- Fixed an issue found by kernel test robot
- Dropped max735x property and custom IRQ check
- Added MAX7357 config register defines instead of magic values
- Renamed vcc-supply to vdd-supply
Patrick Rudolph (3):
dt-bindings: i2c: Add Maxim MAX735x/MAX736x variants
i2c: muxes: pca954x: Add MAX735x/MAX736x support
i2c: muxes: pca954x: Add regulator support
.../bindings/i2c/i2c-mux-pca954x.yaml | 44 ++++--
drivers/i2c/muxes/Kconfig | 4 +-
drivers/i2c/muxes/i2c-mux-pca954x.c | 126 ++++++++++++++++--
3 files changed, 153 insertions(+), 21 deletions(-)
--
2.34.1
Add a vdd regulator and enable it for boards that have the
mux powered off by default.
Signed-off-by: Patrick Rudolph <[email protected]>
Reviewed-by: Peter Rosin <[email protected]>
---
drivers/i2c/muxes/i2c-mux-pca954x.c | 34 ++++++++++++++++++++++++-----
1 file changed, 29 insertions(+), 5 deletions(-)
diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
index 122b7a28fc60..6c43d420e349 100644
--- a/drivers/i2c/muxes/i2c-mux-pca954x.c
+++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
@@ -49,6 +49,7 @@
#include <linux/module.h>
#include <linux/pm.h>
#include <linux/property.h>
+#include <linux/regulator/consumer.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <dt-bindings/mux/mux.h>
@@ -119,6 +120,7 @@ struct pca954x {
struct irq_domain *irq;
unsigned int irq_mask;
raw_spinlock_t lock;
+ struct regulator *supply;
};
/* Provide specs for the PCA954x and MAX735x types we know about */
@@ -459,6 +461,9 @@ static void pca954x_cleanup(struct i2c_mux_core *muxc)
struct pca954x *data = i2c_mux_priv(muxc);
int c, irq;
+ if (!IS_ERR_OR_NULL(data->supply))
+ regulator_disable(data->supply);
+
if (data->irq) {
for (c = 0; c < data->chip->nchans; c++) {
irq = irq_find_mapping(data->irq, c);
@@ -513,15 +518,32 @@ static int pca954x_probe(struct i2c_client *client,
pca954x_select_chan, pca954x_deselect_mux);
if (!muxc)
return -ENOMEM;
+
data = i2c_mux_priv(muxc);
i2c_set_clientdata(client, muxc);
data->client = client;
+ data->supply = devm_regulator_get(dev, "vdd");
+ if (IS_ERR(data->supply)) {
+ ret = PTR_ERR(data->supply);
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "Failed to request regulator: %d\n", ret);
+ return ret;
+ }
+
+ ret = regulator_enable(data->supply);
+ if (ret) {
+ dev_err(dev, "Failed to enable regulator: %d\n", ret);
+ return ret;
+ }
+
/* Reset the mux if a reset GPIO is specified. */
gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
- if (IS_ERR(gpio))
- return PTR_ERR(gpio);
+ if (IS_ERR(gpio)) {
+ ret = PTR_ERR(gpio);
+ goto fail_cleanup;
+ }
if (gpio) {
udelay(1);
gpiod_set_value_cansleep(gpio, 0);
@@ -538,7 +560,7 @@ static int pca954x_probe(struct i2c_client *client,
ret = i2c_get_device_id(client, &id);
if (ret && ret != -EOPNOTSUPP)
- return ret;
+ goto fail_cleanup;
if (!ret &&
(id.manufacturer_id != data->chip->id.manufacturer_id ||
@@ -546,7 +568,8 @@ static int pca954x_probe(struct i2c_client *client,
dev_warn(dev, "unexpected device id %03x-%03x-%x\n",
id.manufacturer_id, id.part_id,
id.die_revision);
- return -ENODEV;
+ ret = -ENODEV;
+ goto fail_cleanup;
}
}
@@ -565,7 +588,8 @@ static int pca954x_probe(struct i2c_client *client,
ret = pca954x_init(client, data);
if (ret < 0) {
dev_warn(dev, "probe failed\n");
- return -ENODEV;
+ ret = -ENODEV;
+ goto fail_cleanup;
}
ret = pca954x_irq_setup(muxc);
--
2.35.1
Add support for the following Maxim chips using the existing PCA954x
driver:
- MAX7356
- MAX7357
- MAX7358
- MAX7367
- MAX7368
- MAX7369
All added Maxim chips behave like the PCA954x, where a single SMBUS byte
write selects up to 8 channels to be bridged to the primary bus.
The MAX7357 and MAX7358 have 6 additional registers called enhanced mode
in the following paragraphs. While the MAX7357 exposes those registers
without a special sequence, the MAX7358 requires an unlock sequence.
The enhanced mode allows to configure optional features which are nice to
have on a I2C mux, but are not mandatory for it's general operation.
As I don't have a MAX7358 for testing the special unlock sequence the
enhanced mode isn't used on the MAX7358, but it could be added later
if required.
The MAX7357 enhanced mode is used to configure:
- Disabled interrupts on bus locked up detection
- Enable bus locked-up clearing
- Disconnect only locked bus instead of all channels
While the MAX7357/MAX7358 have interrupt support, they don't act as
interrupt controller like the PCA9545 does. Thus don't enable IRQ support
and handle them like the PCA9548.
Tested using the MAX7357 and verified that the stalled bus is disconnected
while the other channels remain operational.
Signed-off-by: Patrick Rudolph <[email protected]>
---
drivers/i2c/muxes/Kconfig | 4 +-
drivers/i2c/muxes/i2c-mux-pca954x.c | 92 +++++++++++++++++++++++++++--
2 files changed, 90 insertions(+), 6 deletions(-)
diff --git a/drivers/i2c/muxes/Kconfig b/drivers/i2c/muxes/Kconfig
index 1708b1a82da2..2ac99d044199 100644
--- a/drivers/i2c/muxes/Kconfig
+++ b/drivers/i2c/muxes/Kconfig
@@ -65,11 +65,11 @@ config I2C_MUX_PCA9541
will be called i2c-mux-pca9541.
config I2C_MUX_PCA954x
- tristate "NXP PCA954x and PCA984x I2C Mux/switches"
+ tristate "NXP PCA954x/PCA984x and Maxim MAX735x/MAX736x I2C Mux/switches"
depends on GPIOLIB || COMPILE_TEST
help
If you say yes here you get support for the NXP PCA954x
- and PCA984x I2C mux/switch devices.
+ and PCA984x and Maxim MAX735x/MAX736x I2C mux/switch devices.
This driver can also be built as a module. If so, the module
will be called i2c-mux-pca954x.
diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
index 4ad665757dd8..122b7a28fc60 100644
--- a/drivers/i2c/muxes/i2c-mux-pca954x.c
+++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
@@ -4,6 +4,7 @@
*
* Copyright (c) 2008-2009 Rodolfo Giometti <[email protected]>
* Copyright (c) 2008-2009 Eurotech S.p.A. <[email protected]>
+ * Copyright (c) 2022 9elements GmbH <[email protected]>
*
* This module supports the PCA954x and PCA984x series of I2C multiplexer/switch
* chips made by NXP Semiconductors.
@@ -11,6 +12,12 @@
* PCA9540, PCA9542, PCA9543, PCA9544, PCA9545, PCA9546, PCA9547,
* PCA9548, PCA9846, PCA9847, PCA9848 and PCA9849.
*
+ * It's also compatible to Maxims MAX735x I2C switch chips, which are controlled
+ * as the NXP PCA9548 and the MAX736x chips that act like the PCA9544.
+ *
+ * This includes the:
+ * MAX7356, MAX7357, MAX7358, MAX7367, MAX7368 and MAX7369
+ *
* These chips are all controlled via the I2C bus itself, and all have a
* single 8-bit register. The upstream "parent" bus fans out to two,
* four, or eight downstream busses or channels; which of these
@@ -50,7 +57,30 @@
#define PCA954X_IRQ_OFFSET 4
+/*
+ * MAX7357 exposes 7 registers without extra commands which allow to configure
+ * additional features. Disable interrupts, enable bus locked-up clearing,
+ * isolate only the locked channel instead of all channels.
+ */
+#define MAX7357_CONF_INT_ENABLE BIT(0)
+#define MAX7357_CONF_FLUSH_OUT BIT(1)
+#define MAX7357_CONF_RELEASE_INT BIT(2)
+#define MAX7357_CONF_LOCK_UP_CLEAR BIT(3)
+#define MAX7357_CONF_DISCON_SINGLE_CHAN BIT(4)
+#define MAX7357_CONF_BUS_LOCKUP_DETECTION BIT(5)
+#define MAX7357_CONF_ENABLE_BASIC_MODE BIT(6)
+#define MAX7357_CONF_PRECONNECT_TEST BIT(7)
+
+#define MAX7357_CONF_DEFAULTS (MAX7357_CONF_FLUSH_OUT | \
+ MAX7357_CONF_DISCON_SINGLE_CHAN)
+
enum pca_type {
+ max_7367,
+ max_7368,
+ max_7369,
+ max_7356,
+ max_7357,
+ max_7358,
pca_9540,
pca_9542,
pca_9543,
@@ -69,6 +99,7 @@ struct chip_desc {
u8 nchans;
u8 enable; /* used for muxes only */
u8 has_irq;
+ u8 maxim_enhanced_mode;
enum muxtype {
pca954x_ismux = 0,
pca954x_isswi
@@ -90,8 +121,42 @@ struct pca954x {
raw_spinlock_t lock;
};
-/* Provide specs for the PCA954x types we know about */
+/* Provide specs for the PCA954x and MAX735x types we know about */
static const struct chip_desc chips[] = {
+ [max_7356] = {
+ .nchans = 8,
+ .muxtype = pca954x_isswi,
+ .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
+ },
+ [max_7357] = {
+ .nchans = 8,
+ .muxtype = pca954x_isswi,
+ .maxim_enhanced_mode = 1,
+ .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
+ },
+ [max_7358] = {
+ .nchans = 8,
+ .muxtype = pca954x_isswi,
+ .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
+ },
+ [max_7367] = {
+ .nchans = 4,
+ .muxtype = pca954x_isswi,
+ .has_irq = 1,
+ .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
+ },
+ [max_7368] = {
+ .nchans = 4,
+ .muxtype = pca954x_isswi,
+ .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
+ },
+ [max_7369] = {
+ .nchans = 4,
+ .enable = 0x4,
+ .muxtype = pca954x_ismux,
+ .has_irq = 1,
+ .id = { .manufacturer_id = I2C_DEVICE_ID_NONE },
+ },
[pca_9540] = {
.nchans = 2,
.enable = 0x4,
@@ -177,6 +242,12 @@ static const struct chip_desc chips[] = {
};
static const struct i2c_device_id pca954x_id[] = {
+ { "max7356", max_7356 },
+ { "max7357", max_7357 },
+ { "max7358", max_7358 },
+ { "max7367", max_7367 },
+ { "max7368", max_7368 },
+ { "max7369", max_7369 },
{ "pca9540", pca_9540 },
{ "pca9542", pca_9542 },
{ "pca9543", pca_9543 },
@@ -194,6 +265,12 @@ static const struct i2c_device_id pca954x_id[] = {
MODULE_DEVICE_TABLE(i2c, pca954x_id);
static const struct of_device_id pca954x_of_match[] = {
+ { .compatible = "maxim,max7356", .data = &chips[max_7356] },
+ { .compatible = "maxim,max7357", .data = &chips[max_7357] },
+ { .compatible = "maxim,max7358", .data = &chips[max_7358] },
+ { .compatible = "maxim,max7367", .data = &chips[max_7367] },
+ { .compatible = "maxim,max7368", .data = &chips[max_7368] },
+ { .compatible = "maxim,max7369", .data = &chips[max_7369] },
{ .compatible = "nxp,pca9540", .data = &chips[pca_9540] },
{ .compatible = "nxp,pca9542", .data = &chips[pca_9542] },
{ .compatible = "nxp,pca9543", .data = &chips[pca_9543] },
@@ -401,9 +478,16 @@ static int pca954x_init(struct i2c_client *client, struct pca954x *data)
else
data->last_chan = 0; /* Disconnect multiplexer */
- ret = i2c_smbus_write_byte(client, data->last_chan);
- if (ret < 0)
- data->last_chan = 0;
+ if (data->chip->maxim_enhanced_mode) {
+ ret = i2c_smbus_write_byte_data(client, data->last_chan,
+ MAX7357_CONF_DEFAULTS);
+ if (ret < 0)
+ data->last_chan = 0;
+ } else {
+ ret = i2c_smbus_write_byte(client, data->last_chan);
+ if (ret < 0)
+ data->last_chan = 0;
+ }
return ret;
}
--
2.35.1