Re: [PATCH] hwmon: (pmbus) Add driver fpr Infineon IR35201
From: Guenter Roeck
Date: Thu Jul 20 2023 - 15:23:02 EST
On 7/20/23 11:35, Marty E. Plummer wrote:
On Thu, Jul 20, 2023 at 07:00:39AM -0700, Guenter Roeck wrote:
Maybe.On 7/20/23 04:58, Marty E. Plummer wrote:
The IR35201 is a dual-loop digital multi-phase buck controller designed for CPU voltage regulation.
Signed-off-by: Marty E. Plummer <hanetzer@xxxxxxxxxxxxx>
---
Documentation/hwmon/index.rst | 1 +
Documentation/hwmon/ir35201.rst | 63 +++++++++++++++++++++++
drivers/hwmon/pmbus/Kconfig | 9 ++++
drivers/hwmon/pmbus/Makefile | 1 +
drivers/hwmon/pmbus/ir35201.c | 89 +++++++++++++++++++++++++++++++++
5 files changed, 163 insertions(+)
create mode 100644 Documentation/hwmon/ir35201.rst
create mode 100644 drivers/hwmon/pmbus/ir35201.c
diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst
index 042e1cf9501b..5b44a268de0d 100644
--- a/Documentation/hwmon/index.rst
+++ b/Documentation/hwmon/index.rst
@@ -87,6 +87,7 @@ Hardware Monitoring Kernel Drivers
ina3221
inspur-ipsps1
intel-m10-bmc-hwmon
+ ir35201
ir35221
ir38064
ir36021
diff --git a/Documentation/hwmon/ir35201.rst b/Documentation/hwmon/ir35201.rst
new file mode 100644
index 000000000000..6ca34d4b02a3
--- /dev/null
+++ b/Documentation/hwmon/ir35201.rst
@@ -0,0 +1,63 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+Kernel driver ir35201
+=====================
+
+Supported chips:
+
+ * Infineon IR35201
+
+ Prefix: ir35201
+ Addresses scanned: -
+
+ Datasheet: Publicly available at the Infineon website
+ https://www.infineon.com/dgdl/Infineon-IR35201MTRPBF-DS-v01_00-EN.pdf?fileId=5546d462576f347501579c95d19772b5
+
+Authors:
+ - Marty E. Plummer <hanetzer@xxxxxxxxxxxxx>
+
+Description
+-----------
+
+The IR35201 is a dual-loop digital multi-phase buck controller designed for
+CPU voltage regulation.
+
+Usage Notes
+-----------
+
+This driver does not probe for PMBus devices. You will have to instantiate
+devices explicitly.
+
+Sysfs attributes
+----------------
+
+======================= ===========================
+curr1_label "iin"
+curr1_input Measured input current
+curr1_alarm Input fault alarm
+
+curr2_label "iout1"
+curr2_input Measured output current
+curr2_alarm Output over-current alarm
+
+in1_label "vin"
+in1_input Measured input voltage
+in1_alarm Input under-voltage alarm
+
+in2_label "vout1"
+in2_input Measured output voltage
+in2_alarm Output over-voltage alarm
+
+power1_label "pin"
+power1_input Measured input power
+power1_alarm Input under-voltage alarm
+
+power2_label "pout1"
+power2_input Measured output power
+
+temp1_input Measured temperature
+temp1_alarm Temperature alarm
+
+temp2_input Measured other loop temperature
+temp2_alarm Temperature alarm
+======================= ===========================
diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index 270b6336b76d..7180823b15bb 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -123,6 +123,15 @@ config SENSORS_INSPUR_IPSPS
This driver can also be built as a module. If so, the module will
be called inspur-ipsps.
+config SENSORS_IR35201
+ tristate "Infineon IR35201"
+ help
+ If you say yes here you get hardware monitoring support for the
+ Infineon IR35201 controller.
+
+ This driver can also be built as a module. If so, the module will
+ be called ir35201.
+
config SENSORS_IR35221
tristate "Infineon IR35221"
help
diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
index 84ee960a6c2d..40729dd14e7a 100644
--- a/drivers/hwmon/pmbus/Makefile
+++ b/drivers/hwmon/pmbus/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_SENSORS_FSP_3Y) += fsp-3y.o
obj-$(CONFIG_SENSORS_IBM_CFFPS) += ibm-cffps.o
obj-$(CONFIG_SENSORS_DPS920AB) += dps920ab.o
obj-$(CONFIG_SENSORS_INSPUR_IPSPS) += inspur-ipsps.o
+obj-$(CONFIG_SENSORS_IR35201) += ir35201.o
obj-$(CONFIG_SENSORS_IR35221) += ir35221.o
obj-$(CONFIG_SENSORS_IR36021) += ir36021.o
obj-$(CONFIG_SENSORS_IR38064) += ir38064.o
diff --git a/drivers/hwmon/pmbus/ir35201.c b/drivers/hwmon/pmbus/ir35201.c
new file mode 100644
index 000000000000..77f77057175a
--- /dev/null
+++ b/drivers/hwmon/pmbus/ir35201.c
@@ -0,0 +1,89 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Hardware monitoring driver for Infineon IR35201
+ */
+
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include "pmbus.h"
+
+static struct pmbus_driver_info ir35201_info = {
+ .pages = 1,
+ .format[PSC_VOLTAGE_IN] = linear,
+ .format[PSC_VOLTAGE_OUT] = linear,
+ .format[PSC_CURRENT_IN] = linear,
+ .format[PSC_CURRENT_OUT] = linear,
+ .format[PSC_POWER] = linear,
+ .format[PSC_TEMPERATURE] = linear,
+ .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT
+ | PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT
+ | PMBUS_HAVE_PIN | PMBUS_HAVE_POUT
+ | PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2
+ | PMBUS_HAVE_STATUS_TEMP,
Several supported status registers are missing.
Maybe. Did the best I could with this and another datasheet (ir36* iirc)
open at the same time and both source files open for comparison, and the
output from sensors with this patch, with allowances for variations
in temps, matches more or less what HWINFO64 outputs on a windows pe
based build of hiren's boot cd.
STATUS_INPUT, STATUS_IOUT, and STATUS_VOUT are supported according
to the datasheet. Do you have reason to believe that this is incorrect ?
If so, I would want to see a comment in the driver explaining that the
datasheet is wrong and doesn't support those registers.
+};
+
+static int ir35201_probe(struct i2c_client *client)
+{
+ u8 buf[I2C_SMBUS_BLOCK_MAX];
+ int ret;
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_READ_BYTE_DATA
+ | I2C_FUNC_SMBUS_READ_WORD_DATA
+ | I2C_FUNC_SMBUS_READ_BLOCK_DATA))
+ return -ENODEV;
+
+ ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, buf);
+ if (ret < 0) {
+ dev_err(&client->dev, "Failed to read PMBUS_MFR_ID\n");
+ return ret;
+ }
+ if (ret != 2 || strncmp(buf, "IR", strlen("IR"))) {
+ dev_err(&client->dev, "MFR_ID unrecognized\n");
+ return -ENODEV;
+ }
+
Did you actually test this ? Datasheet says it is "ASCII 52 49" which
would make it "RI" like IR35221, not "IR". Problem though is that it
seems like the register is writeable via some USER programming,
making it unreliable.
Yes, I did. And strangely enough, it reads 'backwards' or so, relative
to the 35221. I almost sent this along without removing the debugging
pr_infos I had in this area to check that. drove me bonkers a bit.
+ ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf);
+ if (ret < 0) {
+ dev_err(&client->dev, "Failed to read PMBUS_MFR_MODEL\n");
+ return ret;
+ }
+ if (ret != 1 || buf[0] != 0x50) {
+ dev_err(&client->dev, "MFR_MODEL unrecognized\n");
+ return -ENODEV;
+ }
+
The datasheet suggests that PMBUS_MFR_ID and PMBUS_MFR_MODEL can differ based
on some USER register programming. I would suggest to read IC_DEVICE_ID instead
and compare against that (which s supposed to be 0x4d).
Somehow I missed that, but it was on my 'to-check' list. I think the
issue may have arose from my datasheet comparison, as the ir36* doesn't
have such a register listed.
Different series, probably different microcontroller and different microcode.
On a higher level, I don't see anything special in this chip. Would it be possible
to just add it to pmbus.c ? Something like
{"ir35201", (kernel_ulong_t)&pmbus_info_one},
Honestly, I was wondering about folding this and the other very similar
IR3* chips into one driver. Should be doable? But I guess this approach
works as well; in fact, during my investigation phase I stuck the pmbus
driver onto the correct i2c address to get an easy way to read stuff
from the chip (tbh I'm surprised that this far along in linux we don't
have anything other than pmbus_peek to poke for info; maybe i2c-tools
can do it but I can't seem to make it work like I'd expect).
This isn't about "doable". We don't want to add new drivers just for fun
and/or "because it works as well". A new driver should only be added if
needed. It was done, for example, for IR35221 because that chip has
non-standard registers which we want to have supported.
Unless I am missing something, IR35201 only supports standard commands.
So the question is: Is the new driver really needed ? It appears you are
saying that, no, it isn't needed. Add the chip to pmbus.c as I suggested above.
If and only if that doesn't work we can talk about a new driver.
Thanks,
Guenter