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authorVadim Pasternak <vadimp@nvidia.com>2020-09-26 23:49:56 +0300
committerGuenter Roeck <linux@roeck-us.net>2020-10-04 18:40:10 +0300
commit2c6fcbb211494f1ff6ef384776944b9e04f4c14c (patch)
treef3644557dd277a9af93099b9de35540280819269 /drivers/hwmon
parentc073292b166a9a0d4d2df605fcbca1ed887aa307 (diff)
downloadlinux-2c6fcbb211494f1ff6ef384776944b9e04f4c14c.tar.xz
hwmon: (pmbus) Add support for MPS Multi-phase mp2975 controller
Add support for mp295 device from Monolithic Power Systems, Inc. (MPS) vendor. This is a dual-loop, digital, multi-phase controller. This device: - Supports two power rail. - Provides 8 pulse-width modulations (PWMs), and can be configured up to 8-phase operation for rail 1 and up to 4-phase operation for rail 2. - Supports two pages 0 and 1 for telemetry and also pages 2 and 3 for configuration. - Can configured VOUT readout in direct or VID format and allows setting of different formats on rails 1 and 2. For VID the following protocols are available: VR13 mode with 5-mV DAC; VR13 mode with 10-mV DAC, IMVP9 mode with 5-mV DAC. Signed-off-by: Vadim Pasternak <vadimp@nvidia.com> Link: https://lore.kernel.org/r/20200926204957.10268-2-vadimp@nvidia.com [groeck: Cleaned up a couple of error returns; fixed up API changes] Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'drivers/hwmon')
-rw-r--r--drivers/hwmon/pmbus/Kconfig9
-rw-r--r--drivers/hwmon/pmbus/Makefile1
-rw-r--r--drivers/hwmon/pmbus/mp2975.c769
3 files changed, 779 insertions, 0 deletions
diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index db90e0018948..a25faf69fce3 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -211,6 +211,15 @@ config SENSORS_MAX8688
This driver can also be built as a module. If so, the module will
be called max8688.
+config SENSORS_MP2975
+ tristate "MPS MP2975"
+ help
+ If you say yes here you get hardware monitoring support for MPS
+ MP2975 Dual Loop Digital Multi-Phase Controller.
+
+ This driver can also be built as a module. If so, the module will
+ be called mp2975.
+
config SENSORS_PXE1610
tristate "Infineon PXE1610"
help
diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
index da41d22be1c9..4c97ad0bd791 100644
--- a/drivers/hwmon/pmbus/Makefile
+++ b/drivers/hwmon/pmbus/Makefile
@@ -24,6 +24,7 @@ obj-$(CONFIG_SENSORS_MAX20751) += max20751.o
obj-$(CONFIG_SENSORS_MAX31785) += max31785.o
obj-$(CONFIG_SENSORS_MAX34440) += max34440.o
obj-$(CONFIG_SENSORS_MAX8688) += max8688.o
+obj-$(CONFIG_SENSORS_MP2975) += mp2975.o
obj-$(CONFIG_SENSORS_PXE1610) += pxe1610.o
obj-$(CONFIG_SENSORS_TPS40422) += tps40422.o
obj-$(CONFIG_SENSORS_TPS53679) += tps53679.o
diff --git a/drivers/hwmon/pmbus/mp2975.c b/drivers/hwmon/pmbus/mp2975.c
new file mode 100644
index 000000000000..1c3e2a9453b1
--- /dev/null
+++ b/drivers/hwmon/pmbus/mp2975.c
@@ -0,0 +1,769 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Hardware monitoring driver for MPS Multi-phase Digital VR Controllers
+ *
+ * Copyright (C) 2020 Nvidia Technologies Ltd.
+ */
+
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include "pmbus.h"
+
+/* Vendor specific registers. */
+#define MP2975_MFR_APS_HYS_R2 0x0d
+#define MP2975_MFR_SLOPE_TRIM3 0x1d
+#define MP2975_MFR_VR_MULTI_CONFIG_R1 0x0d
+#define MP2975_MFR_VR_MULTI_CONFIG_R2 0x1d
+#define MP2975_MFR_APS_DECAY_ADV 0x56
+#define MP2975_MFR_DC_LOOP_CTRL 0x59
+#define MP2975_MFR_OCP_UCP_PHASE_SET 0x65
+#define MP2975_MFR_VR_CONFIG1 0x68
+#define MP2975_MFR_READ_CS1_2 0x82
+#define MP2975_MFR_READ_CS3_4 0x83
+#define MP2975_MFR_READ_CS5_6 0x84
+#define MP2975_MFR_READ_CS7_8 0x85
+#define MP2975_MFR_READ_CS9_10 0x86
+#define MP2975_MFR_READ_CS11_12 0x87
+#define MP2975_MFR_READ_IOUT_PK 0x90
+#define MP2975_MFR_READ_POUT_PK 0x91
+#define MP2975_MFR_READ_VREF_R1 0xa1
+#define MP2975_MFR_READ_VREF_R2 0xa3
+#define MP2975_MFR_OVP_TH_SET 0xe5
+#define MP2975_MFR_UVP_SET 0xe6
+
+#define MP2975_VOUT_FORMAT BIT(15)
+#define MP2975_VID_STEP_SEL_R1 BIT(4)
+#define MP2975_IMVP9_EN_R1 BIT(13)
+#define MP2975_VID_STEP_SEL_R2 BIT(3)
+#define MP2975_IMVP9_EN_R2 BIT(12)
+#define MP2975_PRT_THRES_DIV_OV_EN BIT(14)
+#define MP2975_DRMOS_KCS GENMASK(13, 12)
+#define MP2975_PROT_DEV_OV_OFF 10
+#define MP2975_PROT_DEV_OV_ON 5
+#define MP2975_SENSE_AMPL BIT(11)
+#define MP2975_SENSE_AMPL_UNIT 1
+#define MP2975_SENSE_AMPL_HALF 2
+#define MP2975_VIN_UV_LIMIT_UNIT 8
+
+#define MP2975_MAX_PHASE_RAIL1 8
+#define MP2975_MAX_PHASE_RAIL2 4
+#define MP2975_PAGE_NUM 2
+
+#define MP2975_RAIL2_FUNC (PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT | \
+ PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | \
+ PMBUS_PHASE_VIRTUAL)
+
+struct mp2975_data {
+ struct pmbus_driver_info info;
+ int vout_scale;
+ int vid_step[MP2975_PAGE_NUM];
+ int vref[MP2975_PAGE_NUM];
+ int vref_off[MP2975_PAGE_NUM];
+ int vout_max[MP2975_PAGE_NUM];
+ int vout_ov_fixed[MP2975_PAGE_NUM];
+ int vout_format[MP2975_PAGE_NUM];
+ int curr_sense_gain[MP2975_PAGE_NUM];
+};
+
+#define to_mp2975_data(x) container_of(x, struct mp2975_data, info)
+
+static int mp2975_read_byte_data(struct i2c_client *client, int page, int reg)
+{
+ switch (reg) {
+ case PMBUS_VOUT_MODE:
+ /*
+ * Enforce VOUT direct format, since device allows to set the
+ * different formats for the different rails. Conversion from
+ * VID to direct provided by driver internally, in case it is
+ * necessary.
+ */
+ return PB_VOUT_MODE_DIRECT;
+ default:
+ return -ENODATA;
+ }
+}
+
+static int
+mp2975_read_word_helper(struct i2c_client *client, int page, int phase, u8 reg,
+ u16 mask)
+{
+ int ret = pmbus_read_word_data(client, page, phase, reg);
+
+ return (ret > 0) ? ret & mask : ret;
+}
+
+static int
+mp2975_vid2direct(int vrf, int val)
+{
+ switch (vrf) {
+ case vr12:
+ if (val >= 0x01)
+ return 250 + (val - 1) * 5;
+ break;
+ case vr13:
+ if (val >= 0x01)
+ return 500 + (val - 1) * 10;
+ break;
+ case imvp9:
+ if (val >= 0x01)
+ return 200 + (val - 1) * 10;
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int
+mp2975_read_phase(struct i2c_client *client, struct mp2975_data *data,
+ int page, int phase, u8 reg)
+{
+ int ph_curr, ret;
+
+ ret = pmbus_read_word_data(client, page, phase, reg);
+ if (ret < 0)
+ return ret;
+
+ if (!((phase + 1) % MP2975_PAGE_NUM))
+ ret >>= 8;
+ ret &= 0xff;
+
+ /*
+ * Output value is calculated as: (READ_CSx / 80 – 1.23) / (Kcs * Rcs)
+ * where:
+ * - Kcs is the DrMOS current sense gain of power stage, which is
+ * obtained from the register MP2975_MFR_VR_CONFIG1, bits 13-12 with
+ * the following selection of DrMOS (data->curr_sense_gain[page]):
+ * 00b - 5µA/A, 01b - 8.5µA/A, 10b - 9.7µA/A, 11b - 10µA/A.
+ * - Rcs is the internal phase current sense resistor which is constant
+ * value 1kΩ.
+ */
+ ph_curr = ret * 100 - 9800;
+
+ /*
+ * Current phase sensing, providing by the device is not accurate
+ * for the light load. This because sampling of current occurrence of
+ * bit weight has a big deviation for light load. For handling such
+ * case phase current is represented as the maximum between the value
+ * calculated above and total rail current divided by number phases.
+ */
+ ret = pmbus_read_word_data(client, page, phase, PMBUS_READ_IOUT);
+ if (ret < 0)
+ return ret;
+
+ return max_t(int, DIV_ROUND_CLOSEST(ret, data->info.phases[page]),
+ DIV_ROUND_CLOSEST(ph_curr, data->curr_sense_gain[page]));
+}
+
+static int
+mp2975_read_phases(struct i2c_client *client, struct mp2975_data *data,
+ int page, int phase)
+{
+ int ret;
+
+ if (page) {
+ switch (phase) {
+ case 0 ... 1:
+ ret = mp2975_read_phase(client, data, page, phase,
+ MP2975_MFR_READ_CS7_8);
+ break;
+ case 2 ... 3:
+ ret = mp2975_read_phase(client, data, page, phase,
+ MP2975_MFR_READ_CS9_10);
+ break;
+ case 4 ... 5:
+ ret = mp2975_read_phase(client, data, page, phase,
+ MP2975_MFR_READ_CS11_12);
+ break;
+ default:
+ return -ENODATA;
+ }
+ } else {
+ switch (phase) {
+ case 0 ... 1:
+ ret = mp2975_read_phase(client, data, page, phase,
+ MP2975_MFR_READ_CS1_2);
+ break;
+ case 2 ... 3:
+ ret = mp2975_read_phase(client, data, page, phase,
+ MP2975_MFR_READ_CS3_4);
+ break;
+ case 4 ... 5:
+ ret = mp2975_read_phase(client, data, page, phase,
+ MP2975_MFR_READ_CS5_6);
+ break;
+ case 6 ... 7:
+ ret = mp2975_read_phase(client, data, page, phase,
+ MP2975_MFR_READ_CS7_8);
+ break;
+ case 8 ... 9:
+ ret = mp2975_read_phase(client, data, page, phase,
+ MP2975_MFR_READ_CS9_10);
+ break;
+ case 10 ... 11:
+ ret = mp2975_read_phase(client, data, page, phase,
+ MP2975_MFR_READ_CS11_12);
+ break;
+ default:
+ return -ENODATA;
+ }
+ }
+ return ret;
+}
+
+static int mp2975_read_word_data(struct i2c_client *client, int page,
+ int phase, int reg)
+{
+ const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
+ struct mp2975_data *data = to_mp2975_data(info);
+ int ret;
+
+ switch (reg) {
+ case PMBUS_OT_FAULT_LIMIT:
+ ret = mp2975_read_word_helper(client, page, phase, reg,
+ GENMASK(7, 0));
+ break;
+ case PMBUS_VIN_OV_FAULT_LIMIT:
+ ret = mp2975_read_word_helper(client, page, phase, reg,
+ GENMASK(7, 0));
+ if (ret < 0)
+ return ret;
+
+ ret = DIV_ROUND_CLOSEST(ret, MP2975_VIN_UV_LIMIT_UNIT);
+ break;
+ case PMBUS_VOUT_OV_FAULT_LIMIT:
+ /*
+ * Register provides two values for over-voltage protection
+ * threshold for fixed (ovp2) and tracking (ovp1) modes. The
+ * minimum of these two values is provided as over-voltage
+ * fault alarm.
+ */
+ ret = mp2975_read_word_helper(client, page, phase,
+ MP2975_MFR_OVP_TH_SET,
+ GENMASK(2, 0));
+ if (ret < 0)
+ return ret;
+
+ ret = min_t(int, data->vout_max[page] + 50 * (ret + 1),
+ data->vout_ov_fixed[page]);
+ break;
+ case PMBUS_VOUT_UV_FAULT_LIMIT:
+ ret = mp2975_read_word_helper(client, page, phase,
+ MP2975_MFR_UVP_SET,
+ GENMASK(2, 0));
+ if (ret < 0)
+ return ret;
+
+ ret = DIV_ROUND_CLOSEST(data->vref[page] * 10 - 50 *
+ (ret + 1) * data->vout_scale, 10);
+ break;
+ case PMBUS_READ_VOUT:
+ ret = mp2975_read_word_helper(client, page, phase, reg,
+ GENMASK(11, 0));
+ if (ret < 0)
+ return ret;
+
+ /*
+ * READ_VOUT can be provided in VID or direct format. The
+ * format type is specified by bit 15 of the register
+ * MP2975_MFR_DC_LOOP_CTRL. The driver enforces VOUT direct
+ * format, since device allows to set the different formats for
+ * the different rails and also all VOUT limits registers are
+ * provided in a direct format. In case format is VID - convert
+ * to direct.
+ */
+ if (data->vout_format[page] == vid)
+ ret = mp2975_vid2direct(info->vrm_version[page], ret);
+ break;
+ case PMBUS_VIRT_READ_POUT_MAX:
+ ret = mp2975_read_word_helper(client, page, phase,
+ MP2975_MFR_READ_POUT_PK,
+ GENMASK(12, 0));
+ if (ret < 0)
+ return ret;
+
+ ret = DIV_ROUND_CLOSEST(ret, 4);
+ break;
+ case PMBUS_VIRT_READ_IOUT_MAX:
+ ret = mp2975_read_word_helper(client, page, phase,
+ MP2975_MFR_READ_IOUT_PK,
+ GENMASK(12, 0));
+ if (ret < 0)
+ return ret;
+
+ ret = DIV_ROUND_CLOSEST(ret, 4);
+ break;
+ case PMBUS_READ_IOUT:
+ ret = mp2975_read_phases(client, data, page, phase);
+ if (ret < 0)
+ return ret;
+
+ break;
+ case PMBUS_UT_WARN_LIMIT:
+ case PMBUS_UT_FAULT_LIMIT:
+ case PMBUS_VIN_UV_WARN_LIMIT:
+ case PMBUS_VIN_UV_FAULT_LIMIT:
+ case PMBUS_VOUT_UV_WARN_LIMIT:
+ case PMBUS_VOUT_OV_WARN_LIMIT:
+ case PMBUS_VIN_OV_WARN_LIMIT:
+ case PMBUS_IIN_OC_FAULT_LIMIT:
+ case PMBUS_IOUT_OC_LV_FAULT_LIMIT:
+ case PMBUS_IIN_OC_WARN_LIMIT:
+ case PMBUS_IOUT_OC_WARN_LIMIT:
+ case PMBUS_IOUT_OC_FAULT_LIMIT:
+ case PMBUS_IOUT_UC_FAULT_LIMIT:
+ case PMBUS_POUT_OP_FAULT_LIMIT:
+ case PMBUS_POUT_OP_WARN_LIMIT:
+ case PMBUS_PIN_OP_WARN_LIMIT:
+ return -ENXIO;
+ default:
+ return -ENODATA;
+ }
+
+ return ret;
+}
+
+static int mp2975_identify_multiphase_rail2(struct i2c_client *client)
+{
+ int ret;
+
+ /*
+ * Identify multiphase for rail 2 - could be from 0 to 4.
+ * In case phase number is zero – only page zero is supported
+ */
+ ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, 2);
+ if (ret < 0)
+ return ret;
+
+ /* Identify multiphase for rail 2 - could be from 0 to 4. */
+ ret = i2c_smbus_read_word_data(client, MP2975_MFR_VR_MULTI_CONFIG_R2);
+ if (ret < 0)
+ return ret;
+
+ ret &= GENMASK(2, 0);
+ return (ret >= 4) ? 4 : ret;
+}
+
+static void mp2975_set_phase_rail1(struct pmbus_driver_info *info)
+{
+ int i;
+
+ for (i = 0 ; i < info->phases[0]; i++)
+ info->pfunc[i] = PMBUS_HAVE_IOUT;
+}
+
+static void
+mp2975_set_phase_rail2(struct pmbus_driver_info *info, int num_phases)
+{
+ int i;
+
+ /* Set phases for rail 2 from upper to lower. */
+ for (i = 1; i <= num_phases; i++)
+ info->pfunc[MP2975_MAX_PHASE_RAIL1 - i] = PMBUS_HAVE_IOUT;
+}
+
+static int
+mp2975_identify_multiphase(struct i2c_client *client, struct mp2975_data *data,
+ struct pmbus_driver_info *info)
+{
+ int num_phases2, ret;
+
+ ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, 2);
+ if (ret < 0)
+ return ret;
+
+ /* Identify multiphase for rail 1 - could be from 1 to 8. */
+ ret = i2c_smbus_read_word_data(client, MP2975_MFR_VR_MULTI_CONFIG_R1);
+ if (ret <= 0)
+ return ret;
+
+ info->phases[0] = ret & GENMASK(3, 0);
+
+ /*
+ * The device provides a total of 8 PWM pins, and can be configured
+ * to different phase count applications for rail 1 and rail 2.
+ * Rail 1 can be set to 8 phases, while rail 2 can only be set to 4
+ * phases at most. When rail 1’s phase count is configured as 0, rail
+ * 1 operates with 1-phase DCM. When rail 2 phase count is configured
+ * as 0, rail 2 is disabled.
+ */
+ if (info->phases[0] > MP2975_MAX_PHASE_RAIL1)
+ return -EINVAL;
+
+ mp2975_set_phase_rail1(info);
+ num_phases2 = min(MP2975_MAX_PHASE_RAIL1 - info->phases[0],
+ MP2975_MAX_PHASE_RAIL2);
+ if (info->phases[1] && info->phases[1] <= num_phases2)
+ mp2975_set_phase_rail2(info, num_phases2);
+
+ return 0;
+}
+
+static int
+mp2975_identify_vid(struct i2c_client *client, struct mp2975_data *data,
+ struct pmbus_driver_info *info, u32 reg, int page,
+ u32 imvp_bit, u32 vr_bit)
+{
+ int ret;
+
+ /* Identify VID mode and step selection. */
+ ret = i2c_smbus_read_word_data(client, reg);
+ if (ret < 0)
+ return ret;
+
+ if (ret & imvp_bit) {
+ info->vrm_version[page] = imvp9;
+ data->vid_step[page] = MP2975_PROT_DEV_OV_OFF;
+ } else if (ret & vr_bit) {
+ info->vrm_version[page] = vr12;
+ data->vid_step[page] = MP2975_PROT_DEV_OV_ON;
+ } else {
+ info->vrm_version[page] = vr13;
+ data->vid_step[page] = MP2975_PROT_DEV_OV_OFF;
+ }
+
+ return 0;
+}
+
+static int
+mp2975_identify_rails_vid(struct i2c_client *client, struct mp2975_data *data,
+ struct pmbus_driver_info *info)
+{
+ int ret;
+
+ ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, 2);
+ if (ret < 0)
+ return ret;
+
+ /* Identify VID mode for rail 1. */
+ ret = mp2975_identify_vid(client, data, info,
+ MP2975_MFR_VR_MULTI_CONFIG_R1, 0,
+ MP2975_IMVP9_EN_R1, MP2975_VID_STEP_SEL_R1);
+ if (ret < 0)
+ return ret;
+
+ /* Identify VID mode for rail 2, if connected. */
+ if (info->phases[1])
+ ret = mp2975_identify_vid(client, data, info,
+ MP2975_MFR_VR_MULTI_CONFIG_R2, 1,
+ MP2975_IMVP9_EN_R2,
+ MP2975_VID_STEP_SEL_R2);
+ return ret;
+}
+
+static int
+mp2975_current_sense_gain_get(struct i2c_client *client,
+ struct mp2975_data *data)
+{
+ int i, ret;
+
+ /*
+ * Obtain DrMOS current sense gain of power stage from the register
+ * MP2975_MFR_VR_CONFIG1, bits 13-12. The value is selected as below:
+ * 00b - 5µA/A, 01b - 8.5µA/A, 10b - 9.7µA/A, 11b - 10µA/A. Other
+ * values are invalid.
+ */
+ for (i = 0 ; i < data->info.pages; i++) {
+ ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, i);
+ if (ret < 0)
+ return ret;
+ ret = i2c_smbus_read_word_data(client,
+ MP2975_MFR_VR_CONFIG1);
+ if (ret < 0)
+ return ret;
+
+ switch ((ret & MP2975_DRMOS_KCS) >> 12) {
+ case 0:
+ data->curr_sense_gain[i] = 50;
+ break;
+ case 1:
+ data->curr_sense_gain[i] = 85;
+ break;
+ case 2:
+ data->curr_sense_gain[i] = 97;
+ break;
+ default:
+ data->curr_sense_gain[i] = 100;
+ break;
+ }
+ }
+
+ return 0;
+}
+
+static int
+mp2975_vref_get(struct i2c_client *client, struct mp2975_data *data,
+ struct pmbus_driver_info *info)
+{
+ int ret;
+
+ ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, 3);
+ if (ret < 0)
+ return ret;
+
+ /* Get voltage reference value for rail 1. */
+ ret = i2c_smbus_read_word_data(client, MP2975_MFR_READ_VREF_R1);
+ if (ret < 0)
+ return ret;
+
+ data->vref[0] = ret * data->vid_step[0];
+
+ /* Get voltage reference value for rail 2, if connected. */
+ if (data->info.pages == MP2975_PAGE_NUM) {
+ ret = i2c_smbus_read_word_data(client, MP2975_MFR_READ_VREF_R2);
+ if (ret < 0)
+ return ret;
+
+ data->vref[1] = ret * data->vid_step[1];
+ }
+ return 0;
+}
+
+static int
+mp2975_vref_offset_get(struct i2c_client *client, struct mp2975_data *data,
+ int page)
+{
+ int ret;
+
+ ret = i2c_smbus_read_word_data(client, MP2975_MFR_OVP_TH_SET);
+ if (ret < 0)
+ return ret;
+
+ switch ((ret & GENMASK(5, 3)) >> 3) {
+ case 1:
+ data->vref_off[page] = 140;
+ break;
+ case 2:
+ data->vref_off[page] = 220;
+ break;
+ case 4:
+ data->vref_off[page] = 400;
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int
+mp2975_vout_max_get(struct i2c_client *client, struct mp2975_data *data,
+ struct pmbus_driver_info *info, int page)
+{
+ int ret;
+
+ /* Get maximum reference voltage of VID-DAC in VID format. */
+ ret = i2c_smbus_read_word_data(client, PMBUS_VOUT_MAX);
+ if (ret < 0)
+ return ret;
+
+ data->vout_max[page] = mp2975_vid2direct(info->vrm_version[page], ret &
+ GENMASK(8, 0));
+ return 0;
+}
+
+static int
+mp2975_identify_vout_format(struct i2c_client *client,
+ struct mp2975_data *data, int page)
+{
+ int ret;
+
+ ret = i2c_smbus_read_word_data(client, MP2975_MFR_DC_LOOP_CTRL);
+ if (ret < 0)
+ return ret;
+
+ if (ret & MP2975_VOUT_FORMAT)
+ data->vout_format[page] = vid;
+ else
+ data->vout_format[page] = direct;
+ return 0;
+}
+
+static int
+mp2975_vout_ov_scale_get(struct i2c_client *client, struct mp2975_data *data,
+ struct pmbus_driver_info *info)
+{
+ int thres_dev, sense_ampl, ret;
+
+ ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, 0);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * Get divider for over- and under-voltage protection thresholds
+ * configuration from the Advanced Options of Auto Phase Shedding and
+ * decay register.
+ */
+ ret = i2c_smbus_read_word_data(client, MP2975_MFR_APS_DECAY_ADV);
+ if (ret < 0)
+ return ret;
+ thres_dev = ret & MP2975_PRT_THRES_DIV_OV_EN ? MP2975_PROT_DEV_OV_ON :
+ MP2975_PROT_DEV_OV_OFF;
+
+ /* Select the gain of remote sense amplifier. */
+ ret = i2c_smbus_read_word_data(client, PMBUS_VOUT_SCALE_LOOP);
+ if (ret < 0)
+ return ret;
+ sense_ampl = ret & MP2975_SENSE_AMPL ? MP2975_SENSE_AMPL_HALF :
+ MP2975_SENSE_AMPL_UNIT;
+
+ data->vout_scale = sense_ampl * thres_dev;
+
+ return 0;
+}
+
+static int
+mp2975_vout_per_rail_config_get(struct i2c_client *client,
+ struct mp2975_data *data,
+ struct pmbus_driver_info *info)
+{
+ int i, ret;
+
+ for (i = 0; i < data->info.pages; i++) {
+ ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, i);
+ if (ret < 0)
+ return ret;
+
+ /* Obtain voltage reference offsets. */
+ ret = mp2975_vref_offset_get(client, data, i);
+ if (ret < 0)
+ return ret;
+
+ /* Obtain maximum voltage values. */
+ ret = mp2975_vout_max_get(client, data, info, i);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * Get VOUT format for READ_VOUT command : VID or direct.
+ * Pages on same device can be configured with different
+ * formats.
+ */
+ ret = mp2975_identify_vout_format(client, data, i);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * Set over-voltage fixed value. Thresholds are provided as
+ * fixed value, and tracking value. The minimum of them are
+ * exposed as over-voltage critical threshold.
+ */
+ data->vout_ov_fixed[i] = data->vref[i] +
+ DIV_ROUND_CLOSEST(data->vref_off[i] *
+ data->vout_scale,
+ 10);
+ }
+
+ return 0;
+}
+
+static struct pmbus_driver_info mp2975_info = {
+ .pages = 1,
+ .format[PSC_VOLTAGE_IN] = linear,
+ .format[PSC_VOLTAGE_OUT] = direct,
+ .format[PSC_TEMPERATURE] = direct,
+ .format[PSC_CURRENT_IN] = linear,
+ .format[PSC_CURRENT_OUT] = direct,
+ .format[PSC_POWER] = direct,
+ .m[PSC_TEMPERATURE] = 1,
+ .m[PSC_VOLTAGE_OUT] = 1,
+ .R[PSC_VOLTAGE_OUT] = 3,
+ .m[PSC_CURRENT_OUT] = 1,
+ .m[PSC_POWER] = 1,
+ .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
+ PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
+ PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP | PMBUS_HAVE_POUT |
+ PMBUS_HAVE_PIN | PMBUS_HAVE_STATUS_INPUT | PMBUS_PHASE_VIRTUAL,
+ .read_byte_data = mp2975_read_byte_data,
+ .read_word_data = mp2975_read_word_data,
+};
+
+static int mp2975_probe(struct i2c_client *client)
+{
+ struct pmbus_driver_info *info;
+ struct mp2975_data *data;
+ int ret;
+
+ data = devm_kzalloc(&client->dev, sizeof(struct mp2975_data),
+ GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ memcpy(&data->info, &mp2975_info, sizeof(*info));
+ info = &data->info;
+
+ /* Identify multiphase configuration for rail 2. */
+ ret = mp2975_identify_multiphase_rail2(client);
+ if (ret < 0)
+ return ret;
+
+ if (ret) {
+ /* Two rails are connected. */
+ data->info.pages = MP2975_PAGE_NUM;
+ data->info.phases[1] = ret;
+ data->info.func[1] = MP2975_RAIL2_FUNC;
+ }
+
+ /* Identify multiphase configuration. */
+ ret = mp2975_identify_multiphase(client, data, info);
+ if (ret)
+ return ret;
+
+ /* Identify VID setting per rail. */
+ ret = mp2975_identify_rails_vid(client, data, info);
+ if (ret < 0)
+ return ret;
+
+ /* Obtain current sense gain of power stage. */
+ ret = mp2975_current_sense_gain_get(client, data);
+ if (ret)
+ return ret;
+
+ /* Obtain voltage reference values. */
+ ret = mp2975_vref_get(client, data, info);
+ if (ret)
+ return ret;
+
+ /* Obtain vout over-voltage scales. */
+ ret = mp2975_vout_ov_scale_get(client, data, info);
+ if (ret < 0)
+ return ret;
+
+ /* Obtain offsets, maximum and format for vout. */
+ ret = mp2975_vout_per_rail_config_get(client, data, info);
+ if (ret)
+ return ret;
+
+ return pmbus_do_probe(client, info);
+}
+
+static const struct i2c_device_id mp2975_id[] = {
+ {"mp2975", 0},
+ {}
+};
+
+MODULE_DEVICE_TABLE(i2c, mp2975_id);
+
+static const struct of_device_id __maybe_unused mp2975_of_match[] = {
+ {.compatible = "mps,mp2975"},
+ {}
+};
+MODULE_DEVICE_TABLE(of, mp2975_of_match);
+
+static struct i2c_driver mp2975_driver = {
+ .driver = {
+ .name = "mp2975",
+ .of_match_table = of_match_ptr(mp2975_of_match),
+ },
+ .probe_new = mp2975_probe,
+ .remove = pmbus_do_remove,
+ .id_table = mp2975_id,
+};
+
+module_i2c_driver(mp2975_driver);
+
+MODULE_AUTHOR("Vadim Pasternak <vadimp@nvidia.com>");
+MODULE_DESCRIPTION("PMBus driver for MPS MP2975 device");
+MODULE_LICENSE("GPL");