From patchwork Sat Sep 26 20:49:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Vadim Pasternak X-Patchwork-Id: 11801641 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 010046CB for ; Sat, 26 Sep 2020 20:50:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D5AD020759 for ; Sat, 26 Sep 2020 20:50:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726311AbgIZUuL (ORCPT ); Sat, 26 Sep 2020 16:50:11 -0400 Received: from mail-il-dmz.mellanox.com ([193.47.165.129]:45465 "EHLO mellanox.co.il" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727114AbgIZUuL (ORCPT ); Sat, 26 Sep 2020 16:50:11 -0400 Received: from Internal Mail-Server by MTLPINE1 (envelope-from vadimp@nvidia.com) with SMTP; 26 Sep 2020 23:50:00 +0300 Received: from r-build-lowlevel.mtr.labs.mlnx. (r-build-lowlevel.mtr.labs.mlnx [10.209.0.190]) by labmailer.mlnx (8.13.8/8.13.8) with ESMTP id 08QKnxqC000484; Sat, 26 Sep 2020 23:50:00 +0300 From: Vadim Pasternak To: linux@roeck-us.net, robh+dt@kernel.org Cc: linux-hwmon@vger.kernel.org, devicetree@vger.kernel.org, Vadim Pasternak Subject: [PATCH hwmon-next v4 1/2] hwmon: (pmbus) Add support for MPS Multi-phase mp2975 controller Date: Sat, 26 Sep 2020 23:49:56 +0300 Message-Id: <20200926204957.10268-2-vadimp@nvidia.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20200926204957.10268-1-vadimp@nvidia.com> References: <20200926204957.10268-1-vadimp@nvidia.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org 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 --- v3->v4 Comments pointed out by Guenter: - Drop redundant 'return' from mp2975_identify_multiphase_rail2(). - Fix phases assignment in mp2975_set_phase_rail2(). - Fix range for the number of phases in mp2975_set_multiphase_rail2(). - Drop mp2975_set_multiphase_rail2, call instead directly mp2975_set_phase_rail2(), since the phases range is already validated for rail 2. - Fix handling for the case of zero number of phases for rail 1 in mp2975_identify_multiphase(), which is valid case. - Simplify logic for rail1 and rail2 setting handling in mp2975_identify_multiphase(). - Line length limit is now 100, but 'checkpatch' scripts is still consider it as error. - Modify 'switch' statement in mp2975_current_sense_gain_get(). - Fix misspelled comment in mp2975_probe(). v1->v2 Comments pointed out by Guenter: - Add doc fail to the patch#1 (it was sent as separate patch). - Use standard define for VOUT mode format. - Simplify logic in mp2975_read_phase(). - Simplify calculation of phase current in mp2975_read_phase(). - Modify return code handling in mp2975_read_word_data(). - Add missed error handling in mp2975_read_word_data(). - Drop 'fallthrough;' in mp2975_read_word_data(). - Handle error code in mp2975_identify_multiphase_rail2(). - Handle error code in mp2975_identify_multiphase(). - Drop 'goto' in mp2975_vout_per_rail_config_get() and mp2975_probe(). --- Documentation/hwmon/mp2975.rst | 116 +++++++ drivers/hwmon/pmbus/Kconfig | 9 + drivers/hwmon/pmbus/Makefile | 1 + drivers/hwmon/pmbus/mp2975.c | 772 +++++++++++++++++++++++++++++++++++++++++ 4 files changed, 898 insertions(+) create mode 100644 Documentation/hwmon/mp2975.rst create mode 100644 drivers/hwmon/pmbus/mp2975.c diff --git a/Documentation/hwmon/mp2975.rst b/Documentation/hwmon/mp2975.rst new file mode 100644 index 000000000000..5b0609c62f48 --- /dev/null +++ b/Documentation/hwmon/mp2975.rst @@ -0,0 +1,116 @@ +.. SPDX-License-Identifier: GPL-2.0 + +Kernel driver mp2975 +==================== + +Supported chips: + + * MPS MP12254 + + Prefix: 'mp2975' + +Author: + + Vadim Pasternak + +Description +----------- + +This driver implements support for Monolithic Power Systems, Inc. (MPS) +vendor dual-loop, digital, multi-phase controller MP2975. + +This device: +- Supports up to 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. + +Device supports: +- SVID interface. +- AVSBus interface. + +Device complaint with: +- PMBus rev 1.3 interface. + +Device supports direct format for reading output current, output voltage, +input and output power and temperature. +Device supports linear format for reading input voltage and input power. +Device supports VID and direct formats for reading output voltage. +The below VID modes are supported: VR12, VR13, IMVP9. + +The driver provides the next attributes for the current: +- for current in: input, maximum alarm; +- for current out input, maximum alarm and highest values; +- for phase current: input and label. +attributes. +The driver exports the following attributes via the 'sysfs' files, where +- 'n' is number of telemetry pages (from 1 to 2); +- 'k' is number of configured phases (from 1 to 8); +- indexes 1, 1*n for "iin"; +- indexes n+1, n+2 for "iout"; +- indexes 2*n+1 ... 2*n + k for phases. + +**curr[1-{2n}]_alarm** + +**curr[{n+1}-{n+2}]_highest** + +**curr[1-{2n+k}]_input** + +**curr[1-{2n+k}]_label** + +The driver provides the next attributes for the voltage: +- for voltage in: input, high critical threshold, high critical alarm, all only + from page 0; +- for voltage out: input, low and high critical thresholds, low and high + critical alarms, from pages 0 and 1; +The driver exports the following attributes via the 'sysfs' files, where +- 'n' is number of telemetry pages (from 1 to 2); +- indexes 1 for "iin"; +- indexes n+1, n+2 for "vout"; + +**in[1-{2n+1}]_crit** + +**in[1-{2n+1}]_crit_alarm** + +**in[1-{2n+1}]_input** + +**in[1-{2n+1}]_label** + +**in[2-{n+1}]_lcrit** + +**in[2-{n+1}1_lcrit_alarm** + +The driver provides the next attributes for the power: +- for power in alarm and input. +- for power out: highest and input. +The driver exports the following attributes via the 'sysfs' files, where +- 'n' is number of telemetry pages (from 1 to 2); +- indexes 1 for "pin"; +- indexes n+1, n+2 for "pout"; + +**power1_alarm** + +**power[2-{n+1}]_highest** + +**power[1-{2n+1}]_input** + +**power[1-{2n+1}]_label** + +The driver provides the next attributes for the temperature (only from page 0): + + +**temp1_crit** + +**temp1_crit_alarm** + +**temp1_input** + +**temp1_max** + +**temp1_max_alarm** diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig index e35db489b76f..1e6157e85437 100644 --- a/drivers/hwmon/pmbus/Kconfig +++ b/drivers/hwmon/pmbus/Kconfig @@ -200,6 +200,15 @@ 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 c4b15db996ad..0e2832e73cfc 100644 --- a/drivers/hwmon/pmbus/Makefile +++ b/drivers/hwmon/pmbus/Makefile @@ -23,6 +23,7 @@ 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..f2f3e74c4953 --- /dev/null +++ b/drivers/hwmon/pmbus/mp2975.c @@ -0,0 +1,772 @@ +// 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 +#include +#include +#include +#include +#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) + thres_dev = ret & MP2975_PRT_THRES_DIV_OV_EN ? + MP2975_PROT_DEV_OV_ON : MP2975_PROT_DEV_OV_OFF; + else + return ret; + + /* Select the gain of remote sense amplifier. */ + ret = i2c_smbus_read_word_data(client, PMBUS_VOUT_SCALE_LOOP); + if (ret >= 0) + sense_ampl = ret & MP2975_SENSE_AMPL ? MP2975_SENSE_AMPL_HALF : + MP2975_SENSE_AMPL_UNIT; + else + return ret; + + 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, + const struct i2c_device_id *id) +{ + 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, id, 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 = mp2975_probe, + .remove = pmbus_do_remove, + .id_table = mp2975_id, +}; + +module_i2c_driver(mp2975_driver); + +MODULE_AUTHOR("Vadim Pasternak "); +MODULE_DESCRIPTION("PMBus driver for MPS MP2975 device"); +MODULE_LICENSE("GPL");