Adds Multi-function devices driver for SMpro co-processor found on the
Mt.Jade hardware reference platform with Ampere's Altra processor family.
Signed-off-by: Quan Nguyen <quan@xxxxxxxxxxxxxxxxxxxxxx>
---
Changes in v9:
+ Rename smpro-mfd.c to smpro-core.c [Lee Jones]
+ Fix include files in alphabetical order [Lee Jones]
+ Add defines to avoid using magic numbers [Lee Jones]
+ Return -EINVAL if device does not match [Lee Jones]
+ Remove unneccessary comment [Lee Jones]
+ Refactor error path handling in smpro_core_read/write() [Quan]
Changes in v8:
+ None
Changes in v7:
+ Smpro-mfd now significant changes in compare with simple-mfd-i2c
driver, remove the copyright note about simple-mfd-i2c [Quan]
+ Install bus->read/write() to handle multiple types of bus
access. [Quan]
+ Update license to MODULE_LICENSE("GPL") [Quan]
+ Add others minor refactor the code [Quan]
Changes in v6:
+ Update license part to reflect that this driver is clone from
simple-mfd-i2c driver [Quan]
Changes in v5:
+ Dropped the use of simple-mfd-i2c driver [Quan]
+ Introduced drivers/mfd/smpro-mfd.c driver to instantiate
sub-devices. This is to avoid DT nodes without resource issue [Quan]
+ Revised commit message [Quan]
Changes in v4:
+ Add "depends on I2C" to fix build issue found by kernel test
robot [Guenter]
Changes in v3:
+ None
Changes in v2:
+ Used 'struct of_device_id's .data attribute [Lee Jones]
drivers/mfd/Kconfig | 12 ++++
drivers/mfd/Makefile | 1 +
drivers/mfd/smpro-core.c | 138 +++++++++++++++++++++++++++++++++++++++
3 files changed, 151 insertions(+)
create mode 100644 drivers/mfd/smpro-core.c
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 8b93856de432..9e77f4762999 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -77,6 +77,18 @@ config MFD_AS3711
help
Support for the AS3711 PMIC from AMS
+config MFD_SMPRO
+ tristate "Ampere Computing SMpro core driver"
+ depends on I2C
+ select MFD_CORE
+ select REGMAP_I2C
+ help
+ Say yes here to enable SMpro driver support for Ampere's Altra
+ processor family.
+
+ Ampere's Altra SMpro exposes an I2C regmap interface that can
+ be accessed by child devices.
+
config MFD_AS3722
tristate "ams AS3722 Power Management IC"
select MFD_CORE
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 7ed3ef4a698c..9387c3ddab4e 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -271,6 +271,7 @@ obj-$(CONFIG_MFD_QCOM_PM8008) += qcom-pm8008.o
obj-$(CONFIG_SGI_MFD_IOC3) += ioc3.o
obj-$(CONFIG_MFD_SIMPLE_MFD_I2C) += simple-mfd-i2c.o
+obj-$(CONFIG_MFD_SMPRO) += smpro-core.o
obj-$(CONFIG_MFD_INTEL_M10_BMC) += intel-m10-bmc.o
obj-$(CONFIG_MFD_ATC260X) += atc260x-core.o
diff --git a/drivers/mfd/smpro-core.c b/drivers/mfd/smpro-core.c
new file mode 100644
index 000000000000..d7729cf70378
--- /dev/null
+++ b/drivers/mfd/smpro-core.c
@@ -0,0 +1,138 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Ampere Altra Family SMPro core driver
+ * Copyright (c) 2022, Ampere Computing LLC
+ */
+
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/mfd/core.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/regmap.h>
+
+/* Identification Registers */
+#define MANUFACTURER_ID_REG 0x02
+#define AMPERE_MANUFACTURER_ID 0xCD3A
+
+#define CORE_CE_ERR_DATA 0x82
+#define CORE_UE_ERR_DATA 0x85
+#define MEM_CE_ERR_DATA 0x92
+#define MEM_UE_ERR_DATA 0x95
+#define PCIE_CE_ERR_DATA 0xC2
+#define PCIE_UE_ERR_DATA 0xC5
+#define OTHER_CE_ERR_DATA 0xD2
+#define OTHER_UE_ERR_DATA 0xDA
+
+static int smpro_core_write(void *context, const void *data, size_t count)
+{
+ struct device *dev = context;
+ struct i2c_client *i2c = to_i2c_client(dev);
+ int ret;
+
+ ret = i2c_master_send(i2c, data, count);
+ if (unlikely(ret != count))
+ return (ret < 0) ? ret : -EIO;
+
+ return 0;
+}
+
+static int smpro_core_read(void *context, const void *reg, size_t reg_size,
+ void *val, size_t val_size)
+{
+ struct device *dev = context;
+ struct i2c_client *i2c = to_i2c_client(dev);
+ struct i2c_msg xfer[2];
+ unsigned char buf[2];
+ int ret;
+
+ xfer[0].addr = i2c->addr;
+ xfer[0].flags = 0;
+
+ buf[0] = *(u8 *)reg;
+ buf[1] = val_size;
+ xfer[0].len = 2;
+ xfer[0].buf = buf;
+
+ xfer[1].addr = i2c->addr;
+ xfer[1].flags = I2C_M_RD;
+ xfer[1].len = val_size;
+ xfer[1].buf = val;
+
+ ret = i2c_transfer(i2c->adapter, xfer, 2);
+ if (unlikely(ret != 2))
+ return (ret < 0) ? ret : -EIO;
+
+ return 0;
+}
+
+static const struct regmap_bus smpro_regmap_bus = {
+ .read = smpro_core_read,
+ .write = smpro_core_write,
+ .val_format_endian_default = REGMAP_ENDIAN_BIG,
+};
+
+static bool smpro_core_readable_noinc_reg(struct device *dev, unsigned int reg)
+{
+ return (reg == CORE_CE_ERR_DATA || reg == CORE_UE_ERR_DATA ||
+ reg == MEM_CE_ERR_DATA || reg == MEM_UE_ERR_DATA ||
+ reg == PCIE_CE_ERR_DATA || reg == PCIE_UE_ERR_DATA ||
+ reg == OTHER_CE_ERR_DATA || reg == OTHER_UE_ERR_DATA);
+}
+
+static const struct regmap_config smpro_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 16,
+ .readable_noinc_reg = smpro_core_readable_noinc_reg,
+};
+
+static const struct mfd_cell smpro_devs[] = {
+ MFD_CELL_NAME("smpro-hwmon"),
+ MFD_CELL_NAME("smpro-errmon"),
+ MFD_CELL_NAME("smpro-misc"),
+};
+
+static int smpro_core_probe(struct i2c_client *i2c)
+{
+ const struct regmap_config *config;
+ struct regmap *regmap;
+ unsigned int val;
+ int ret;
+
+ config = device_get_match_data(&i2c->dev);
+ if (!config)
+ return -EINVAL;
+
+ regmap = devm_regmap_init(&i2c->dev, &smpro_regmap_bus, &i2c->dev, config);
+ if (IS_ERR(regmap))
+ return PTR_ERR(regmap);
+
+ ret = regmap_read(regmap, MANUFACTURER_ID_REG, &val);
+ if (ret)
+ return ret;
+
+ if (val != AMPERE_MANUFACTURER_ID)
+ return -ENODEV;
+
+ return devm_mfd_add_devices(&i2c->dev, PLATFORM_DEVID_AUTO,
+ smpro_devs, ARRAY_SIZE(smpro_devs), NULL, 0, NULL);
+}
+
+static const struct of_device_id smpro_core_of_match[] = {
+ { .compatible = "ampere,smpro", .data = &smpro_regmap_config },
+ {}
+};
+MODULE_DEVICE_TABLE(of, smpro_core_of_match);
+
+static struct i2c_driver smpro_core_driver = {
+ .probe_new = smpro_core_probe,
+ .driver = {
+ .name = "smpro-core",
+ .of_match_table = smpro_core_of_match,
+ },
+};
+module_i2c_driver(smpro_core_driver);
+
+MODULE_AUTHOR("Quan Nguyen <quan@xxxxxxxxxxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("SMPRO CORE - I2C driver");
+MODULE_LICENSE("GPL");
--
2.35.1
