Re: [PATCH v6 18/19] platform/x86: intel_pmc_ipc: Convert to MFD

From: Lee Jones
Date: Wed Feb 26 2020 - 03:47:25 EST


On Mon, 17 Feb 2020, Mika Westerberg wrote:

> This driver only creates a bunch of platform devices sharing resources
> belonging to the PMC device. This is pretty much what MFD subsystem is
> for so move the driver there, renaming it to intel_pmc_bxt.c which
> should be more clear what it is.
>
> MFD subsystem provides nice helper APIs for subdevice creation so
> convert the driver to use those. Unfortunately the ACPI device includes
> separate resources for most of the subdevices so we cannot simply call
> mfd_add_devices() to create all of them but instead we need to call it
> separately for each device.
>
> The new MFD driver continues to expose two sysfs attributes that allow
> userspace to send IPC commands to the PMC/SCU to avoid breaking any
> existing applications that may use these. Generally this is bad idea so
> document this in the ABI documentation.
>
> Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> ---
> .../ABI/obsolete/sysfs-driver-intel_pmc_bxt | 22 +
> arch/x86/include/asm/intel_pmc_ipc.h | 47 --
> arch/x86/include/asm/intel_telemetry.h | 1 +
> drivers/mfd/Kconfig | 16 +-
> drivers/mfd/Makefile | 1 +
> drivers/mfd/intel_pmc_bxt.c | 489 +++++++++++++
> drivers/platform/x86/Kconfig | 16 +-
> drivers/platform/x86/Makefile | 1 -
> drivers/platform/x86/intel_pmc_ipc.c | 645 ------------------
> .../platform/x86/intel_telemetry_debugfs.c | 12 +-
> drivers/platform/x86/intel_telemetry_pltdrv.c | 2 +
> drivers/usb/typec/tcpm/Kconfig | 2 +-
> include/linux/mfd/intel_pmc_bxt.h | 21 +
> 13 files changed, 565 insertions(+), 710 deletions(-)
> create mode 100644 Documentation/ABI/obsolete/sysfs-driver-intel_pmc_bxt
> delete mode 100644 arch/x86/include/asm/intel_pmc_ipc.h
> create mode 100644 drivers/mfd/intel_pmc_bxt.c
> delete mode 100644 drivers/platform/x86/intel_pmc_ipc.c
> create mode 100644 include/linux/mfd/intel_pmc_bxt.h

[...]

> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 20b294ef2873..d41a965d819b 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -551,7 +551,7 @@ config INTEL_SOC_PMIC
>
> config INTEL_SOC_PMIC_BXTWC
> tristate "Support for Intel Broxton Whiskey Cove PMIC"
> - depends on INTEL_PMC_IPC
> + depends on MFD_INTEL_PMC_BXT
> select MFD_CORE
> select REGMAP_IRQ
> help
> @@ -632,6 +632,20 @@ config MFD_INTEL_MSIC
> Passage) chip. This chip embeds audio, battery, GPIO, etc.
> devices used in Intel Medfield platforms.
>
> +config MFD_INTEL_PMC_BXT
> + tristate "Intel PMC Driver for Broxton"
> + depends on X86
> + depends on X86_PLATFORM_DEVICES
> + depends on ACPI
> + select INTEL_SCU_IPC
> + select MFD_CORE
> + help
> + This driver provides support for the PMC (Power Management
> + Controller) on Intel Broxton and Apollo Lake. The PMC is a
> + multi-function device that exposes IPC, General Control
> + Register and P-unit access. In addition this creates devices
> + for iTCO watchdog and telemetry that are part of the PMC.
> +
> config MFD_IPAQ_MICRO
> bool "Atmel Micro ASIC (iPAQ h3100/h3600/h3700) Support"
> depends on SA1100_H3100 || SA1100_H3600
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index b83f172545e1..444264d42a20 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -212,6 +212,7 @@ obj-$(CONFIG_MFD_INTEL_LPSS) += intel-lpss.o
> obj-$(CONFIG_MFD_INTEL_LPSS_PCI) += intel-lpss-pci.o
> obj-$(CONFIG_MFD_INTEL_LPSS_ACPI) += intel-lpss-acpi.o
> obj-$(CONFIG_MFD_INTEL_MSIC) += intel_msic.o
> +obj-$(CONFIG_MFD_INTEL_PMC_BXT) += intel_pmc_bxt.o
> obj-$(CONFIG_MFD_PALMAS) += palmas.o
> obj-$(CONFIG_MFD_VIPERBOARD) += viperboard.o
> obj-$(CONFIG_MFD_RC5T583) += rc5t583.o rc5t583-irq.o
> diff --git a/drivers/mfd/intel_pmc_bxt.c b/drivers/mfd/intel_pmc_bxt.c
> new file mode 100644
> index 000000000000..7f743ae205de
> --- /dev/null
> +++ b/drivers/mfd/intel_pmc_bxt.c
> @@ -0,0 +1,489 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for the Intel Broxton PMC
> + *
> + * (C) Copyright 2014 - 2020 Intel Corporation
> + *
> + * This driver is based on Intel SCU IPC driver (intel_scu_ipc.c) by
> + * Sreedhara DS <sreedhara.ds@xxxxxxxxx>
> + *
> + * The PMC running on the ARC processor communicates with another entity
> + * running in the IA core through an IPC mechanism which in turn sends
> + * messages between the IA and the PMC.

Please expand non-universal/non-obvious abbreviations in comments.

> + */
> +
> +#include <linux/acpi.h>
> +#include <linux/delay.h>
> +#include <linux/errno.h>
> +#include <linux/interrupt.h>
> +#include <linux/io-64-nonatomic-lo-hi.h>
> +#include <linux/mfd/core.h>
> +#include <linux/mfd/intel_pmc_bxt.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/platform_data/itco_wdt.h>
> +
> +#include <asm/intel_scu_ipc.h>
> +
> +/* Residency with clock rate at 19.2MHz to usecs */
> +#define S0IX_RESIDENCY_IN_USECS(d, s) \
> +({ \
> + u64 result = 10ull * ((d) + (s)); \
> + do_div(result, 192); \
> + result; \
> +})
> +
> +/* Resources exported from IFWI */
> +#define PLAT_RESOURCE_IPC_INDEX 0
> +#define PLAT_RESOURCE_IPC_SIZE 0x1000
> +#define PLAT_RESOURCE_GCR_OFFSET 0x1000
> +#define PLAT_RESOURCE_GCR_SIZE 0x1000
> +#define PLAT_RESOURCE_BIOS_DATA_INDEX 1
> +#define PLAT_RESOURCE_BIOS_IFACE_INDEX 2
> +#define PLAT_RESOURCE_TELEM_SSRAM_INDEX 3
> +#define PLAT_RESOURCE_ISP_DATA_INDEX 4
> +#define PLAT_RESOURCE_ISP_IFACE_INDEX 5
> +#define PLAT_RESOURCE_GTD_DATA_INDEX 6
> +#define PLAT_RESOURCE_GTD_IFACE_INDEX 7
> +#define PLAT_RESOURCE_ACPI_IO_INDEX 0
> +
> +/*
> + * BIOS does not create an ACPI device for each PMC function, but
> + * exports multiple resources from one ACPI device (IPC) for multiple
> + * functions. This driver is responsible for creating a child device and
> + * to export resources for those functions.
> + */
> +#define TCO_DEVICE_NAME "iTCO_wdt"

This is nearly always horrible.

Please just use the string in it's place.

> +#define SMI_EN_OFFSET 0x40
> +#define SMI_EN_SIZE 4
> +#define TCO_BASE_OFFSET 0x60
> +#define TCO_REGS_SIZE 16

> +#define PUNIT_DEVICE_NAME "intel_punit_ipc"
> +#define TELEMETRY_DEVICE_NAME "intel_telemetry"

As above.

> +#define TELEM_SSRAM_SIZE 240
> +#define TELEM_PMC_SSRAM_OFFSET 0x1B00
> +#define TELEM_PUNIT_SSRAM_OFFSET 0x1A00
> +
> +/* Commands */
> +#define PMC_NORTHPEAK_CTRL 0xED
> +
> +/* PMC_CFG_REG bit masks */
> +#define PMC_CFG_NO_REBOOT_EN BIT(4)
> +
> +/* Index to cells array in below struct */
> +enum {
> + PMC_TCO,
> + PMC_PUNIT,
> + PMC_TELEM,
> +};
> +
> +struct intel_pmc_dev {
> + struct device *dev;
> + struct intel_scu_ipc_dev *scu;
> +
> + struct mfd_cell cells[PMC_TELEM + 1];

Nicer to add a "PMC_DEVICE_MAX" enum and use that.

Why do these even need to be in here?

I would normally suggest creating a cell per device.

> + void __iomem *gcr_mem_base;
> + spinlock_t gcr_lock;
> +
> + struct resource *telem_base;
> +};
> +
> +static inline bool is_gcr_valid(u32 offset)
> +{
> + return offset < PLAT_RESOURCE_GCR_SIZE - 8;
> +}
> +
> +/**
> + * intel_pmc_gcr_read64() - Read a 64-bit PMC GCR register
> + * @pmc: PMC device pointer
> + * @offset: offset of GCR register from GCR address base
> + * @data: data pointer for storing the register output
> + *
> + * Reads the 64-bit PMC GCR register at given offset.
> + *
> + * Return: Negative value on error or 0 on success.
> + */
> +int intel_pmc_gcr_read64(struct intel_pmc_dev *pmc, u32 offset, u64 *data)
> +{
> + if (!is_gcr_valid(offset))
> + return -EINVAL;
> +
> + spin_lock(&pmc->gcr_lock);
> + *data = readq(pmc->gcr_mem_base + offset);
> + spin_unlock(&pmc->gcr_lock);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(intel_pmc_gcr_read64);
> +
> +/**
> + * intel_pmc_gcr_update() - Update PMC GCR register bits
> + * @pmc: PMC device pointer
> + * @offset: offset of GCR register from GCR address base
> + * @mask: bit mask for update operation
> + * @val: update value
> + *
> + * Updates the bits of given GCR register as specified by
> + * @mask and @val.
> + *
> + * Return: Negative value on error or 0 on success.
> + */
> +static int intel_pmc_gcr_update(struct intel_pmc_dev *pmc, u32 offset, u32 mask,
> + u32 val)
> +{
> + u32 new_val;
> +
> + if (!is_gcr_valid(offset))
> + return -EINVAL;
> +
> + spin_lock(&pmc->gcr_lock);
> + new_val = readl(pmc->gcr_mem_base + offset);
> +
> + new_val = (new_val & ~mask) | (val & mask);
> + writel(new_val, pmc->gcr_mem_base + offset);
> +
> + new_val = readl(pmc->gcr_mem_base + offset);
> + spin_unlock(&pmc->gcr_lock);
> +
> + /* Check whether the bit update is successful */
> + return (new_val & mask) != (val & mask) ? -EIO : 0;
> +}
> +
> +/**
> + * intel_pmc_s0ix_counter_read() - Read S0ix residency.
> + * @pmc: PMC device pointer
> + * @data: Out param that contains current S0ix residency count.
> + *
> + * Writes to @data how many usecs the system has been in low-power S0ix
> + * state.
> + *
> + * Return: An error code or 0 on success.
> + */
> +int intel_pmc_s0ix_counter_read(struct intel_pmc_dev *pmc, u64 *data)
> +{
> + u64 deep, shlw;
> +
> + spin_lock(&pmc->gcr_lock);
> + deep = readq(pmc->gcr_mem_base + PMC_GCR_TELEM_DEEP_S0IX_REG);
> + shlw = readq(pmc->gcr_mem_base + PMC_GCR_TELEM_SHLW_S0IX_REG);
> + spin_unlock(&pmc->gcr_lock);
> +
> + *data = S0IX_RESIDENCY_IN_USECS(deep, shlw);
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(intel_pmc_s0ix_counter_read);
> +
> +static ssize_t simplecmd_store(struct device *dev, struct device_attribute *attr,

Header with explanation please.

> + const char *buf, size_t count)
> +{
> + struct intel_pmc_dev *pmc = dev_get_drvdata(dev);
> + struct intel_scu_ipc_dev *scu = pmc->scu;
> + int subcmd;
> + int cmd;
> + int ret;
> +
> + ret = sscanf(buf, "%d %d", &cmd, &subcmd);
> + if (ret != 2) {
> + dev_err(dev, "Invalid values, expected: cmd subcmd\n");
> + return -EINVAL;
> + }
> +
> + ret = intel_scu_ipc_dev_simple_command(scu, cmd, subcmd);
> + return ret ?: count;

Prefer the usual "if (ret) return ret;" over ternary.

> +}
> +static DEVICE_ATTR_WO(simplecmd);
> +
> +static ssize_t northpeak_store(struct device *dev, struct device_attribute *attr,
> + const char *buf, size_t count)

Header with explanation please.

> +{
> + struct intel_pmc_dev *pmc = dev_get_drvdata(dev);
> + struct intel_scu_ipc_dev *scu = pmc->scu;
> + unsigned long val;
> + int subcmd;
> + int ret;
> +
> + ret = kstrtoul(buf, 0, &val);
> + if (ret)
> + return ret;
> +
> + if (val)
> + subcmd = 1;
> + else
> + subcmd = 0;

Comment please.

> + ret = intel_scu_ipc_dev_simple_command(scu, PMC_NORTHPEAK_CTRL, subcmd);
> + return ret ?: count;

As above.

> +}
> +static DEVICE_ATTR_WO(northpeak);
> +
> +static struct attribute *intel_pmc_attrs[] = {
> + &dev_attr_northpeak.attr,
> + &dev_attr_simplecmd.attr,
> + NULL
> +};
> +
> +static const struct attribute_group intel_pmc_group = {
> + .attrs = intel_pmc_attrs,
> +};
> +
> +static const struct attribute_group *intel_pmc_groups[] = {
> + &intel_pmc_group,
> + NULL
> +};
> +
> +/* Templates used to construct MFD cells */
> +
> +static const struct mfd_cell punit = {
> + .name = PUNIT_DEVICE_NAME,

Use proper string please.

> +};
> +
> +static int update_no_reboot_bit(void *priv, bool set)
> +{
> + struct intel_pmc_dev *pmc = priv;
> + u32 bits = PMC_CFG_NO_REBOOT_EN;
> + u32 value = set ? bits : 0;
> +
> + return intel_pmc_gcr_update(pmc, PMC_GCR_PMC_CFG_REG, bits, value);
> +}
> +
> +static const struct itco_wdt_platform_data tco_pdata = {
> + .name = "Apollo Lake SoC",
> + .version = 5,
> + .update_no_reboot_bit = update_no_reboot_bit,
> +};
> +
> +static const struct mfd_cell tco = {
> + .name = TCO_DEVICE_NAME,

Use proper string please.

> + .ignore_resource_conflicts = true,

Why not add tco_pdata here?

> +};
> +
> +static const struct resource telem_res[] = {
> + DEFINE_RES_MEM(TELEM_PUNIT_SSRAM_OFFSET, TELEM_SSRAM_SIZE),
> + DEFINE_RES_MEM(TELEM_PMC_SSRAM_OFFSET, TELEM_SSRAM_SIZE),
> +};
> +
> +static const struct mfd_cell telem = {
> + .name = TELEMETRY_DEVICE_NAME,

Use proper string please.

> + .resources = telem_res,
> + .num_resources = ARRAY_SIZE(telem_res),
> +};
> +
> +static int intel_pmc_get_tco_resources(struct platform_device *pdev,
> + struct intel_pmc_dev *pmc)
> +{
> + struct itco_wdt_platform_data *pdata;
> + struct resource *res, *tco_res;
> +
> + if (acpi_has_watchdog())
> + return 0;
> +
> + res = platform_get_resource(pdev, IORESOURCE_IO,
> + PLAT_RESOURCE_ACPI_IO_INDEX);
> + if (!res) {
> + dev_err(&pdev->dev, "Failed to get IO resource\n");
> + return -EINVAL;
> + }
> +
> + tco_res = devm_kcalloc(&pdev->dev, 2, sizeof(*tco_res), GFP_KERNEL);
> + if (!tco_res)
> + return -ENOMEM;
> +
> + tco_res[0].flags = IORESOURCE_IO;
> + tco_res[0].start = res->start + TCO_BASE_OFFSET;
> + tco_res[0].end = tco_res[0].start + TCO_REGS_SIZE - 1;
> + tco_res[1].flags = IORESOURCE_IO;
> + tco_res[1].start = res->start + SMI_EN_OFFSET;
> + tco_res[1].end = tco_res[1].start + SMI_EN_SIZE - 1;
> +
> + pmc->cells[PMC_TCO].resources = tco_res;
> + pmc->cells[PMC_TCO].num_resources = 2;
> +
> + pdata = devm_kmemdup(&pdev->dev, &tco_pdata, sizeof(*pdata), GFP_KERNEL);
> + if (!pdata)
> + return -ENOMEM;
> +
> + pdata->no_reboot_priv = pmc;

This looks hacky. What are you doing here?

> + pmc->cells[PMC_TCO].platform_data = pdata;
> + pmc->cells[PMC_TCO].pdata_size = sizeof(*pdata);
> +
> + return 0;
> +}
> +
> +static int intel_pmc_get_resources(struct platform_device *pdev,
> + struct intel_pmc_dev *pmc,
> + struct intel_scu_ipc_pdata *pdata)
> +{
> + struct resource *res, *punit_res;
> + struct resource gcr_res;
> + size_t npunit_res = 0;
> + int ret;
> +
> + pdata->irq = platform_get_irq_optional(pdev, 0);
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM,
> + PLAT_RESOURCE_IPC_INDEX);
> + if (!res) {
> + dev_err(&pdev->dev, "Failed to get IPC resource\n");
> + return -EINVAL;
> + }
> +
> + /* IPC registers */
> + pdata->mem.flags = res->flags;
> + pdata->mem.start = res->start;
> + pdata->mem.end = res->start + PLAT_RESOURCE_IPC_SIZE - 1;

Passing register addresses through pdata also looks like a hack.

Why not pass via resources?

> + /* GCR registers */
> + gcr_res.flags = res->flags;
> + gcr_res.start = res->start + PLAT_RESOURCE_GCR_OFFSET;
> + gcr_res.end = gcr_res.start + PLAT_RESOURCE_GCR_SIZE - 1;
> +
> + pmc->gcr_mem_base = devm_ioremap_resource(&pdev->dev, &gcr_res);
> + if (IS_ERR(pmc->gcr_mem_base))
> + return PTR_ERR(pmc->gcr_mem_base);
> +
> + pmc->cells[PMC_TCO] = tco;
> + pmc->cells[PMC_PUNIT] = punit;
> + pmc->cells[PMC_TELEM] = telem;
> +
> + /* iTCO watchdog only if there is no WDAT ACPI table */

This sentence doesn't make sense.

"Only register ... " ?

> + ret = intel_pmc_get_tco_resources(pdev, pmc);
> + if (ret)
> + return ret;
> +
> + punit_res = devm_kcalloc(&pdev->dev, 6, sizeof(*punit_res), GFP_KERNEL);
> + if (!punit_res)
> + return -ENOMEM;
> +
> + /* This is index 0 to cover BIOS data register */

We don't need to know what the indexes are.

Just leave it at "BIOS data register".

> + res = platform_get_resource(pdev, IORESOURCE_MEM,
> + PLAT_RESOURCE_BIOS_DATA_INDEX);
> + if (!res) {
> + dev_err(&pdev->dev, "Failed to get resource of P-unit BIOS data\n");
> + return -EINVAL;
> + }
> + punit_res[npunit_res++] = *res;
> +
> + /* This is index 1 to cover BIOS interface register */
> + res = platform_get_resource(pdev, IORESOURCE_MEM,
> + PLAT_RESOURCE_BIOS_IFACE_INDEX);
> + if (!res) {
> + dev_err(&pdev->dev, "Failed to get resource of P-unit BIOS interface\n");
> + return -EINVAL;
> + }
> + punit_res[npunit_res++] = *res;
> +
> + /* This is index 2 to cover ISP data register, optional */
> + res = platform_get_resource(pdev, IORESOURCE_MEM,
> + PLAT_RESOURCE_ISP_DATA_INDEX);
> + if (res)
> + punit_res[npunit_res++] = *res;
> +
> + /* This is index 3 to cover ISP interface register, optional */
> + res = platform_get_resource(pdev, IORESOURCE_MEM,
> + PLAT_RESOURCE_ISP_IFACE_INDEX);
> + if (res)
> + punit_res[npunit_res++] = *res;
> +
> + /* This is index 4 to cover GTD data register, optional */
> + res = platform_get_resource(pdev, IORESOURCE_MEM,
> + PLAT_RESOURCE_GTD_DATA_INDEX);
> + if (res)
> + punit_res[npunit_res++] = *res;
> +
> + /* This is index 5 to cover GTD interface register, optional */
> + res = platform_get_resource(pdev, IORESOURCE_MEM,
> + PLAT_RESOURCE_GTD_IFACE_INDEX);
> + if (res)
> + punit_res[npunit_res++] = *res;
> +
> + pmc->cells[PMC_PUNIT].resources = punit_res;
> + pmc->cells[PMC_PUNIT].num_resources = npunit_res;
> +
> + /* Telemetry SSRAM is optional */
> + res = platform_get_resource(pdev, IORESOURCE_MEM,
> + PLAT_RESOURCE_TELEM_SSRAM_INDEX);
> + if (res)
> + pmc->telem_base = res;
> +
> + return 0;
> +}
> +
> +static int intel_pmc_create_devices(struct intel_pmc_dev *pmc)
> +{
> + int ret;
> +
> + if (pmc->cells[PMC_TCO].num_resources) {

Why not use the same (only?) condition that could make this false:

if (acpi_has_watchdog())

> + ret = devm_mfd_add_devices(pmc->dev, PLATFORM_DEVID_AUTO,
> + &pmc->cells[PMC_TCO], 1, NULL, 0, NULL);
> + if (ret)
> + return ret;
> + }
> +
> + ret = devm_mfd_add_devices(pmc->dev, PLATFORM_DEVID_AUTO,
> + &pmc->cells[PMC_PUNIT], 1, NULL, 0, NULL);
> + if (ret)
> + return ret;
> +
> + if (pmc->telem_base) {
> + ret = devm_mfd_add_devices(pmc->dev, PLATFORM_DEVID_AUTO,
> + &pmc->cells[PMC_TELEM], 1,
> + pmc->telem_base, 0, NULL);
> + }
> +
> + return ret;
> +}
> +
> +static const struct acpi_device_id intel_pmc_acpi_ids[] = {
> + { "INT34D2" },
> + { }
> +};
> +MODULE_DEVICE_TABLE(acpi, intel_pmc_acpi_ids);
> +
> +static int intel_pmc_probe(struct platform_device *pdev)
> +{
> + struct intel_scu_ipc_pdata pdata = {};
> + struct intel_pmc_dev *pmc;
> + int ret;
> +
> + pmc = devm_kzalloc(&pdev->dev, sizeof(*pmc), GFP_KERNEL);
> + if (!pmc)
> + return -ENOMEM;
> +
> + pmc->dev = &pdev->dev;
> + spin_lock_init(&pmc->gcr_lock);
> +
> + ret = intel_pmc_get_resources(pdev, pmc, &pdata);
> + if (ret) {
> + dev_err(&pdev->dev, "Failed to request resources\n");
> + return ret;
> + }
> +
> + pmc->scu = devm_intel_scu_ipc_register(&pdev->dev, &pdata);
> + if (IS_ERR(pmc->scu))
> + return PTR_ERR(pmc->scu);
> +
> + platform_set_drvdata(pdev, pmc);
> +
> + ret = intel_pmc_create_devices(pmc);
> + if (ret)
> + dev_err(&pdev->dev, "Failed to create PMC devices\n");
> +
> + return ret;
> +}
> +
> +static struct platform_driver intel_pmc_driver = {
> + .probe = intel_pmc_probe,
> + .driver = {
> + .name = "intel_pmc_bxt",
> + .acpi_match_table = intel_pmc_acpi_ids,
> + .dev_groups = intel_pmc_groups,
> + },
> +};
> +

Remove this line.

> +module_platform_driver(intel_pmc_driver);
> +
> +MODULE_AUTHOR("Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>");
> +MODULE_AUTHOR("Zha Qipeng <qipeng.zha@xxxxxxxxx>");
> +MODULE_DESCRIPTION("Intel Broxton PMC driver");
> +MODULE_LICENSE("GPL v2");

[...]

> diff --git a/include/linux/mfd/intel_pmc_bxt.h b/include/linux/mfd/intel_pmc_bxt.h
> new file mode 100644
> index 000000000000..a5fb41910d78
> --- /dev/null
> +++ b/include/linux/mfd/intel_pmc_bxt.h
> @@ -0,0 +1,21 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef MFD_INTEL_PMC_BXT_H
> +#define MFD_INTEL_PMC_BXT_H
> +
> +#include <linux/types.h>
> +
> +/* GCR reg offsets from GCR base */
> +#define PMC_GCR_PMC_CFG_REG 0x08
> +#define PMC_GCR_TELEM_DEEP_S0IX_REG 0x78
> +#define PMC_GCR_TELEM_SHLW_S0IX_REG 0x80
> +
> +/*
> + * Pointer to the PMC device can be obtained by calling
> + * dev_get_drvdata() to the parent MFD device.
> + */
> +struct intel_pmc_dev;

Don't you have a shared header file you can put the definition in
instead?

> +int intel_pmc_s0ix_counter_read(struct intel_pmc_dev *pmc, u64 *data);
> +int intel_pmc_gcr_read64(struct intel_pmc_dev *pmc, u32 offset, u64 *data);
> +
> +#endif /* MFD_INTEL_PMC_BXT_H */

--
Lee Jones [æçæ]
Linaro Services Technical Lead
Linaro.org â Open source software for ARM SoCs
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