2022-01-21 21:57:26

by Patrick Rudolph

[permalink] [raw]
Subject: [v3 0/3] Add support for Maxim MAX735x/MAX736x variants

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 | 43 ++++--
drivers/i2c/muxes/Kconfig | 4 +-
drivers/i2c/muxes/i2c-mux-pca954x.c | 124 ++++++++++++++++--
3 files changed, 150 insertions(+), 21 deletions(-)

--
2.34.1


2022-01-21 21:57:40

by Patrick Rudolph

[permalink] [raw]
Subject: [v3 1/3] dt-bindings: i2c: Add Maxim MAX735x/MAX736x variants

Update the pca954x bindings to add support for the Maxim MAX735x/MAX736x
chips. The functionality will be provided by the exisintg pca954x driver.

While on it make the interrupts support conditionally as not all of the
existing chips have interrupts.

For chips that are powered off by default add an optional regulator
called vdd-supply.

Signed-off-by: Patrick Rudolph <[email protected]>
---
.../bindings/i2c/i2c-mux-pca954x.yaml | 43 ++++++++++++++-----
1 file changed, 33 insertions(+), 10 deletions(-)

diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.yaml b/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.yaml
index 9f1726d0356b..e7650e2a777e 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.yaml
+++ b/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.yaml
@@ -4,21 +4,47 @@
$id: http://devicetree.org/schemas/i2c/i2c-mux-pca954x.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

-title: NXP PCA954x I2C bus switch
+title: NXP PCA954x I2C and compatible bus switches

maintainers:
- Laurent Pinchart <[email protected]>

description:
- The binding supports NXP PCA954x and PCA984x I2C mux/switch devices.
+ The binding supports NXP PCA954x and PCA984x I2C mux/switch devices,
+ and the Maxim MAX735x and MAX736x I2C mux/switch devices.

allOf:
- $ref: /schemas/i2c/i2c-mux.yaml#
+ - if:
+ properties:
+ compatible:
+ contains:
+ enum:
+ - maxim,max7367
+ - maxim,max7369
+ - nxp,pca9542
+ - nxp,pca9543
+ - nxp,pca9544
+ - nxp,pca9545
+ then:
+ properties:
+ interrupts: true
+
+ "#interrupt-cells":
+ const: 2
+
+ interrupt-controller: true

properties:
compatible:
oneOf:
- enum:
+ - maxim,max7356
+ - maxim,max7357
+ - maxim,max7358
+ - maxim,max7367
+ - maxim,max7368
+ - maxim,max7369
- nxp,pca9540
- nxp,pca9542
- nxp,pca9543
@@ -38,14 +64,6 @@ properties:
reg:
maxItems: 1

- interrupts:
- maxItems: 1
-
- "#interrupt-cells":
- const: 2
-
- interrupt-controller: true
-
reset-gpios:
maxItems: 1

@@ -59,6 +77,9 @@ properties:
description: if present, overrides i2c-mux-idle-disconnect
$ref: /schemas/mux/mux-controller.yaml#/properties/idle-state

+ vdd-supply:
+ description: A voltage regulator supplying power to the chip.
+
required:
- compatible
- reg
@@ -79,6 +100,8 @@ examples:
#size-cells = <0>;
reg = <0x74>;

+ vdd-supply = <&p3v3>;
+
interrupt-parent = <&ipic>;
interrupts = <17 IRQ_TYPE_LEVEL_LOW>;
interrupt-controller;
--
2.34.1

2022-01-21 21:57:51

by Patrick Rudolph

[permalink] [raw]
Subject: [v3 2/3] i2c: muxes: pca954x: Add MAX735x/MAX736x support

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 exposes 6 additional registers at Power-On-Reset and is
configured to:
- 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..33b9a6a1fffa 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 Patrick Rudolph <[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 on POR 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 max7357;
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,
+ .max7357 = 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->max7357) {
+ 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;
}
--
2.34.1

2022-02-06 08:34:48

by Rob Herring (Arm)

[permalink] [raw]
Subject: Re: [v3 1/3] dt-bindings: i2c: Add Maxim MAX735x/MAX736x variants

On Thu, Jan 20, 2022 at 01:13:11PM +0100, Patrick Rudolph wrote:
> Update the pca954x bindings to add support for the Maxim MAX735x/MAX736x
> chips. The functionality will be provided by the exisintg pca954x driver.
>
> While on it make the interrupts support conditionally as not all of the
> existing chips have interrupts.
>
> For chips that are powered off by default add an optional regulator
> called vdd-supply.
>
> Signed-off-by: Patrick Rudolph <[email protected]>
> ---
> .../bindings/i2c/i2c-mux-pca954x.yaml | 43 ++++++++++++++-----
> 1 file changed, 33 insertions(+), 10 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.yaml b/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.yaml
> index 9f1726d0356b..e7650e2a777e 100644
> --- a/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.yaml
> +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-pca954x.yaml
> @@ -4,21 +4,47 @@
> $id: http://devicetree.org/schemas/i2c/i2c-mux-pca954x.yaml#
> $schema: http://devicetree.org/meta-schemas/core.yaml#
>
> -title: NXP PCA954x I2C bus switch
> +title: NXP PCA954x I2C and compatible bus switches
>
> maintainers:
> - Laurent Pinchart <[email protected]>
>
> description:
> - The binding supports NXP PCA954x and PCA984x I2C mux/switch devices.
> + The binding supports NXP PCA954x and PCA984x I2C mux/switch devices,
> + and the Maxim MAX735x and MAX736x I2C mux/switch devices.
>
> allOf:
> - $ref: /schemas/i2c/i2c-mux.yaml#
> + - if:
> + properties:
> + compatible:
> + contains:
> + enum:
> + - maxim,max7367
> + - maxim,max7369
> + - nxp,pca9542
> + - nxp,pca9543
> + - nxp,pca9544
> + - nxp,pca9545
> + then:
> + properties:
> + interrupts: true

Now any number of interrupts are valid and undefined.

> +
> + "#interrupt-cells":
> + const: 2
> +
> + interrupt-controller: true
>
> properties:
> compatible:
> oneOf:
> - enum:
> + - maxim,max7356
> + - maxim,max7357
> + - maxim,max7358
> + - maxim,max7367
> + - maxim,max7368
> + - maxim,max7369
> - nxp,pca9540
> - nxp,pca9542
> - nxp,pca9543
> @@ -38,14 +64,6 @@ properties:
> reg:
> maxItems: 1
>
> - interrupts:
> - maxItems: 1
> -
> - "#interrupt-cells":
> - const: 2
> -
> - interrupt-controller: true
> -
> reset-gpios:
> maxItems: 1
>
> @@ -59,6 +77,9 @@ properties:
> description: if present, overrides i2c-mux-idle-disconnect
> $ref: /schemas/mux/mux-controller.yaml#/properties/idle-state
>
> + vdd-supply:
> + description: A voltage regulator supplying power to the chip.
> +
> required:
> - compatible
> - reg
> @@ -79,6 +100,8 @@ examples:
> #size-cells = <0>;
> reg = <0x74>;
>
> + vdd-supply = <&p3v3>;
> +
> interrupt-parent = <&ipic>;
> interrupts = <17 IRQ_TYPE_LEVEL_LOW>;
> interrupt-controller;
> --
> 2.34.1
>
>