Re: [PATCH v6 8/8] mfd: Add support for Intel Sunrisepoint LPSS devices

Lee Jones
2015-07-28T07:48:43Z

On Mon, 27 Jul 2015, Andy Shevchenko wrote:

> The new coming Intel platforms such as Skylake will contain Sunrisepoint PCH.
> The main difference to the previous platforms is that the LPSS devices are
> compound devices where usually main (SPI, HSUART, or I2C) and DMA IPs are
> present.
>
> This patch brings the driver for such devices found on Sunrisepoint PCH.
>
> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> drivers/mfd/Kconfig | 23 ++
> drivers/mfd/Makefile | 3 +
> drivers/mfd/intel-lpss-acpi.c | 84 +++++++
> drivers/mfd/intel-lpss-pci.c | 113 +++++++++
> drivers/mfd/intel-lpss.c | 524 ++++++++++++++++++++++++++++++++++++++++++
> drivers/mfd/intel-lpss.h | 62 +++++
> 6 files changed, 809 insertions(+)
> create mode 100644 drivers/mfd/intel-lpss-acpi.c
> create mode 100644 drivers/mfd/intel-lpss-pci.c
> create mode 100644 drivers/mfd/intel-lpss.c
> create mode 100644 drivers/mfd/intel-lpss.h

Applied, thanks. Pull request to follow.

> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 6538159..268b6dd 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -328,6 +328,29 @@ config INTEL_SOC_PMIC
> thermal, charger and related power management functions
> on these systems.
>
> +config MFD_INTEL_LPSS
> + tristate
> + select COMMON_CLK
> + select MFD_CORE
> +
> +config MFD_INTEL_LPSS_ACPI
> + tristate "Intel Low Power Subsystem support in ACPI mode"
> + select MFD_INTEL_LPSS
> + depends on X86 && ACPI
> + help
> + This driver supports Intel Low Power Subsystem (LPSS) devices such as
> + I2C, SPI and HS-UART starting from Intel Sunrisepoint (Intel Skylake
> + PCH) in ACPI mode.
> +
> +config MFD_INTEL_LPSS_PCI
> + tristate "Intel Low Power Subsystem support in PCI mode"
> + select MFD_INTEL_LPSS
> + depends on X86 && PCI
> + help
> + This driver supports Intel Low Power Subsystem (LPSS) devices such as
> + I2C, SPI and HS-UART starting from Intel Sunrisepoint (Intel Skylake
> + PCH) in PCI mode.
> +
> config MFD_INTEL_MSIC
> bool "Intel MSIC"
> depends on INTEL_SCU_IPC
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index ea40e07..9d730a2 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -161,6 +161,9 @@ obj-$(CONFIG_TPS65911_COMPARATOR) += tps65911-comparator.o
> obj-$(CONFIG_MFD_TPS65090) += tps65090.o
> obj-$(CONFIG_MFD_AAT2870_CORE) += aat2870-core.o
> obj-$(CONFIG_MFD_ATMEL_HLCDC) += atmel-hlcdc.o
> +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-$(CONFIG_MFD_PALMAS) += palmas.o
> obj-$(CONFIG_MFD_VIPERBOARD) += viperboard.o
> diff --git a/drivers/mfd/intel-lpss-acpi.c b/drivers/mfd/intel-lpss-acpi.c
> new file mode 100644
> index 0000000..0d92d73
> --- /dev/null
> +++ b/drivers/mfd/intel-lpss-acpi.c
> @@ -0,0 +1,84 @@
> +/*
> + * Intel LPSS ACPI support.
> + *
> + * Copyright (C) 2015, Intel Corporation
> + *
> + * Authors: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> + * Mika Westerberg <mika.westerberg@linux.intel.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/acpi.h>
> +#include <linux/ioport.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/pm.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/platform_device.h>
> +
> +#include "intel-lpss.h"
> +
> +static const struct intel_lpss_platform_info spt_info = {
> + .clk_rate = 120000000,
> +};
> +
> +static const struct acpi_device_id intel_lpss_acpi_ids[] = {
> + /* SPT */
> + { "INT3446", (kernel_ulong_t)&spt_info },
> + { "INT3447", (kernel_ulong_t)&spt_info },
> + { }
> +};
> +MODULE_DEVICE_TABLE(acpi, intel_lpss_acpi_ids);
> +
> +static int intel_lpss_acpi_probe(struct platform_device *pdev)
> +{
> + struct intel_lpss_platform_info *info;
> + const struct acpi_device_id *id;
> +
> + id = acpi_match_device(intel_lpss_acpi_ids, &pdev->dev);
> + if (!id)
> + return -ENODEV;
> +
> + info = devm_kmemdup(&pdev->dev, (void *)id->driver_data, sizeof(*info),
> + GFP_KERNEL);
> + if (!info)
> + return -ENOMEM;
> +
> + info->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + info->irq = platform_get_irq(pdev, 0);
> +
> + pm_runtime_set_active(&pdev->dev);
> + pm_runtime_enable(&pdev->dev);
> +
> + return intel_lpss_probe(&pdev->dev, info);
> +}
> +
> +static int intel_lpss_acpi_remove(struct platform_device *pdev)
> +{
> + intel_lpss_remove(&pdev->dev);
> + pm_runtime_disable(&pdev->dev);
> +
> + return 0;
> +}
> +
> +static INTEL_LPSS_PM_OPS(intel_lpss_acpi_pm_ops);
> +
> +static struct platform_driver intel_lpss_acpi_driver = {
> + .probe = intel_lpss_acpi_probe,
> + .remove = intel_lpss_acpi_remove,
> + .driver = {
> + .name = "intel-lpss",
> + .acpi_match_table = intel_lpss_acpi_ids,
> + .pm = &intel_lpss_acpi_pm_ops,
> + },
> +};
> +
> +module_platform_driver(intel_lpss_acpi_driver);
> +
> +MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
> +MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
> +MODULE_DESCRIPTION("Intel LPSS ACPI driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/mfd/intel-lpss-pci.c b/drivers/mfd/intel-lpss-pci.c
> new file mode 100644
> index 0000000..9236dff
> --- /dev/null
> +++ b/drivers/mfd/intel-lpss-pci.c
> @@ -0,0 +1,113 @@
> +/*
> + * Intel LPSS PCI support.
> + *
> + * Copyright (C) 2015, Intel Corporation
> + *
> + * Authors: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> + * Mika Westerberg <mika.westerberg@linux.intel.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/ioport.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/pci.h>
> +#include <linux/pm.h>
> +#include <linux/pm_runtime.h>
> +
> +#include "intel-lpss.h"
> +
> +static int intel_lpss_pci_probe(struct pci_dev *pdev,
> + const struct pci_device_id *id)
> +{
> + struct intel_lpss_platform_info *info;
> + int ret;
> +
> + ret = pcim_enable_device(pdev);
> + if (ret)
> + return ret;
> +
> + info = devm_kmemdup(&pdev->dev, (void *)id->driver_data, sizeof(*info),
> + GFP_KERNEL);
> + if (!info)
> + return -ENOMEM;
> +
> + info->mem = &pdev->resource[0];
> + info->irq = pdev->irq;
> +
> + /* Probably it is enough to set this for iDMA capable devices only */
> + pci_set_master(pdev);
> +
> + ret = intel_lpss_probe(&pdev->dev, info);
> + if (ret)
> + return ret;
> +
> + pm_runtime_put(&pdev->dev);
> + pm_runtime_allow(&pdev->dev);
> +
> + return 0;
> +}
> +
> +static void intel_lpss_pci_remove(struct pci_dev *pdev)
> +{
> + pm_runtime_forbid(&pdev->dev);
> + pm_runtime_get_sync(&pdev->dev);
> +
> + intel_lpss_remove(&pdev->dev);
> +}
> +
> +static INTEL_LPSS_PM_OPS(intel_lpss_pci_pm_ops);
> +
> +static const struct intel_lpss_platform_info spt_info = {
> + .clk_rate = 120000000,
> +};
> +
> +static const struct intel_lpss_platform_info spt_uart_info = {
> + .clk_rate = 120000000,
> + .clk_con_id = "baudclk",
> +};
> +
> +static const struct pci_device_id intel_lpss_pci_ids[] = {
> + /* SPT-LP */
> + { PCI_VDEVICE(INTEL, 0x9d27), (kernel_ulong_t)&spt_uart_info },
> + { PCI_VDEVICE(INTEL, 0x9d28), (kernel_ulong_t)&spt_uart_info },
> + { PCI_VDEVICE(INTEL, 0x9d29), (kernel_ulong_t)&spt_info },
> + { PCI_VDEVICE(INTEL, 0x9d2a), (kernel_ulong_t)&spt_info },
> + { PCI_VDEVICE(INTEL, 0x9d60), (kernel_ulong_t)&spt_info },
> + { PCI_VDEVICE(INTEL, 0x9d61), (kernel_ulong_t)&spt_info },
> + { PCI_VDEVICE(INTEL, 0x9d62), (kernel_ulong_t)&spt_info },
> + { PCI_VDEVICE(INTEL, 0x9d63), (kernel_ulong_t)&spt_info },
> + { PCI_VDEVICE(INTEL, 0x9d64), (kernel_ulong_t)&spt_info },
> + { PCI_VDEVICE(INTEL, 0x9d65), (kernel_ulong_t)&spt_info },
> + { PCI_VDEVICE(INTEL, 0x9d66), (kernel_ulong_t)&spt_uart_info },
> + /* SPT-H */
> + { PCI_VDEVICE(INTEL, 0xa127), (kernel_ulong_t)&spt_uart_info },
> + { PCI_VDEVICE(INTEL, 0xa128), (kernel_ulong_t)&spt_uart_info },
> + { PCI_VDEVICE(INTEL, 0xa129), (kernel_ulong_t)&spt_info },
> + { PCI_VDEVICE(INTEL, 0xa12a), (kernel_ulong_t)&spt_info },
> + { PCI_VDEVICE(INTEL, 0xa160), (kernel_ulong_t)&spt_info },
> + { PCI_VDEVICE(INTEL, 0xa161), (kernel_ulong_t)&spt_info },
> + { PCI_VDEVICE(INTEL, 0xa166), (kernel_ulong_t)&spt_uart_info },
> + { }
> +};
> +MODULE_DEVICE_TABLE(pci, intel_lpss_pci_ids);
> +
> +static struct pci_driver intel_lpss_pci_driver = {
> + .name = "intel-lpss",
> + .id_table = intel_lpss_pci_ids,
> + .probe = intel_lpss_pci_probe,
> + .remove = intel_lpss_pci_remove,
> + .driver = {
> + .pm = &intel_lpss_pci_pm_ops,
> + },
> +};
> +
> +module_pci_driver(intel_lpss_pci_driver);
> +
> +MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
> +MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
> +MODULE_DESCRIPTION("Intel LPSS PCI driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/mfd/intel-lpss.c b/drivers/mfd/intel-lpss.c
> new file mode 100644
> index 0000000..fdf4d5c
> --- /dev/null
> +++ b/drivers/mfd/intel-lpss.c
> @@ -0,0 +1,524 @@
> +/*
> + * Intel Sunrisepoint LPSS core support.
> + *
> + * Copyright (C) 2015, Intel Corporation
> + *
> + * Authors: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> + * Mika Westerberg <mika.westerberg@linux.intel.com>
> + * Heikki Krogerus <heikki.krogerus@linux.intel.com>
> + * Jarkko Nikula <jarkko.nikula@linux.intel.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/clkdev.h>
> +#include <linux/clk-provider.h>
> +#include <linux/debugfs.h>
> +#include <linux/idr.h>
> +#include <linux/ioport.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/mfd/core.h>
> +#include <linux/pm_qos.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/seq_file.h>
> +
> +#include "intel-lpss.h"
> +
> +#define LPSS_DEV_OFFSET 0x000
> +#define LPSS_DEV_SIZE 0x200
> +#define LPSS_PRIV_OFFSET 0x200
> +#define LPSS_PRIV_SIZE 0x100
> +#define LPSS_IDMA64_OFFSET 0x800
> +#define LPSS_IDMA64_SIZE 0x800
> +
> +/* Offsets from lpss->priv */
> +#define LPSS_PRIV_RESETS 0x04
> +#define LPSS_PRIV_RESETS_FUNC BIT(2)
> +#define LPSS_PRIV_RESETS_IDMA 0x3
> +
> +#define LPSS_PRIV_ACTIVELTR 0x10
> +#define LPSS_PRIV_IDLELTR 0x14
> +
> +#define LPSS_PRIV_LTR_REQ BIT(15)
> +#define LPSS_PRIV_LTR_SCALE_MASK 0xc00
> +#define LPSS_PRIV_LTR_SCALE_1US 0x800
> +#define LPSS_PRIV_LTR_SCALE_32US 0xc00
> +#define LPSS_PRIV_LTR_VALUE_MASK 0x3ff
> +
> +#define LPSS_PRIV_SSP_REG 0x20
> +#define LPSS_PRIV_SSP_REG_DIS_DMA_FIN BIT(0)
> +
> +#define LPSS_PRIV_REMAP_ADDR_LO 0x40
> +#define LPSS_PRIV_REMAP_ADDR_HI 0x44
> +
> +#define LPSS_PRIV_CAPS 0xfc
> +#define LPSS_PRIV_CAPS_NO_IDMA BIT(8)
> +#define LPSS_PRIV_CAPS_TYPE_SHIFT 4
> +#define LPSS_PRIV_CAPS_TYPE_MASK (0xf << LPSS_PRIV_CAPS_TYPE_SHIFT)
> +
> +/* This matches the type field in CAPS register */
> +enum intel_lpss_dev_type {
> + LPSS_DEV_I2C = 0,
> + LPSS_DEV_UART,
> + LPSS_DEV_SPI,
> +};
> +
> +struct intel_lpss {
> + const struct intel_lpss_platform_info *info;
> + enum intel_lpss_dev_type type;
> + struct clk *clk;
> + struct clk_lookup *clock;
> + const struct mfd_cell *cell;
> + struct device *dev;
> + void __iomem *priv;
> + int devid;
> + u32 caps;
> + u32 active_ltr;
> + u32 idle_ltr;
> + struct dentry *debugfs;
> +};
> +
> +static const struct resource intel_lpss_dev_resources[] = {
> + DEFINE_RES_MEM_NAMED(LPSS_DEV_OFFSET, LPSS_DEV_SIZE, "lpss_dev"),
> + DEFINE_RES_MEM_NAMED(LPSS_PRIV_OFFSET, LPSS_PRIV_SIZE, "lpss_priv"),
> + DEFINE_RES_IRQ(0),
> +};
> +
> +static const struct resource intel_lpss_idma64_resources[] = {
> + DEFINE_RES_MEM(LPSS_IDMA64_OFFSET, LPSS_IDMA64_SIZE),
> + DEFINE_RES_IRQ(0),
> +};
> +
> +#define LPSS_IDMA64_DRIVER_NAME "idma64"
> +
> +/*
> + * Cells needs to be ordered so that the iDMA is created first. This is
> + * because we need to be sure the DMA is available when the host controller
> + * driver is probed.
> + */
> +static const struct mfd_cell intel_lpss_idma64_cell = {
> + .name = LPSS_IDMA64_DRIVER_NAME,
> + .num_resources = ARRAY_SIZE(intel_lpss_idma64_resources),
> + .resources = intel_lpss_idma64_resources,
> +};
> +
> +static const struct mfd_cell intel_lpss_i2c_cell = {
> + .name = "i2c_designware",
> + .num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
> + .resources = intel_lpss_dev_resources,
> +};
> +
> +static const struct mfd_cell intel_lpss_uart_cell = {
> + .name = "dw-apb-uart",
> + .num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
> + .resources = intel_lpss_dev_resources,
> +};
> +
> +static const struct mfd_cell intel_lpss_spi_cell = {
> + .name = "pxa2xx-spi",
> + .num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
> + .resources = intel_lpss_dev_resources,
> +};
> +
> +static DEFINE_IDA(intel_lpss_devid_ida);
> +static struct dentry *intel_lpss_debugfs;
> +
> +static int intel_lpss_request_dma_module(const char *name)
> +{
> + static bool intel_lpss_dma_requested;
> +
> + if (intel_lpss_dma_requested)
> + return 0;
> +
> + intel_lpss_dma_requested = true;
> + return request_module("%s", name);
> +}
> +
> +static void intel_lpss_cache_ltr(struct intel_lpss *lpss)
> +{
> + lpss->active_ltr = readl(lpss->priv + LPSS_PRIV_ACTIVELTR);
> + lpss->idle_ltr = readl(lpss->priv + LPSS_PRIV_IDLELTR);
> +}
> +
> +static int intel_lpss_debugfs_add(struct intel_lpss *lpss)
> +{
> + struct dentry *dir;
> +
> + dir = debugfs_create_dir(dev_name(lpss->dev), intel_lpss_debugfs);
> + if (IS_ERR(dir))
> + return PTR_ERR(dir);
> +
> + /* Cache the values into lpss structure */
> + intel_lpss_cache_ltr(lpss);
> +
> + debugfs_create_x32("capabilities", S_IRUGO, dir, &lpss->caps);
> + debugfs_create_x32("active_ltr", S_IRUGO, dir, &lpss->active_ltr);
> + debugfs_create_x32("idle_ltr", S_IRUGO, dir, &lpss->idle_ltr);
> +
> + lpss->debugfs = dir;
> + return 0;
> +}
> +
> +static void intel_lpss_debugfs_remove(struct intel_lpss *lpss)
> +{
> + debugfs_remove_recursive(lpss->debugfs);
> +}
> +
> +static void intel_lpss_ltr_set(struct device *dev, s32 val)
> +{
> + struct intel_lpss *lpss = dev_get_drvdata(dev);
> + u32 ltr;
> +
> + /*
> + * Program latency tolerance (LTR) accordingly what has been asked
> + * by the PM QoS layer or disable it in case we were passed
> + * negative value or PM_QOS_LATENCY_ANY.
> + */
> + ltr = readl(lpss->priv + LPSS_PRIV_ACTIVELTR);
> +
> + if (val == PM_QOS_LATENCY_ANY || val < 0) {
> + ltr &= ~LPSS_PRIV_LTR_REQ;
> + } else {
> + ltr |= LPSS_PRIV_LTR_REQ;
> + ltr &= ~LPSS_PRIV_LTR_SCALE_MASK;
> + ltr &= ~LPSS_PRIV_LTR_VALUE_MASK;
> +
> + if (val > LPSS_PRIV_LTR_VALUE_MASK)
> + ltr |= LPSS_PRIV_LTR_SCALE_32US | val >> 5;
> + else
> + ltr |= LPSS_PRIV_LTR_SCALE_1US | val;
> + }
> +
> + if (ltr == lpss->active_ltr)
> + return;
> +
> + writel(ltr, lpss->priv + LPSS_PRIV_ACTIVELTR);
> + writel(ltr, lpss->priv + LPSS_PRIV_IDLELTR);
> +
> + /* Cache the values into lpss structure */
> + intel_lpss_cache_ltr(lpss);
> +}
> +
> +static void intel_lpss_ltr_expose(struct intel_lpss *lpss)
> +{
> + lpss->dev->power.set_latency_tolerance = intel_lpss_ltr_set;
> + dev_pm_qos_expose_latency_tolerance(lpss->dev);
> +}
> +
> +static void intel_lpss_ltr_hide(struct intel_lpss *lpss)
> +{
> + dev_pm_qos_hide_latency_tolerance(lpss->dev);
> + lpss->dev->power.set_latency_tolerance = NULL;
> +}
> +
> +static int intel_lpss_assign_devs(struct intel_lpss *lpss)
> +{
> + unsigned int type;
> +
> + type = lpss->caps & LPSS_PRIV_CAPS_TYPE_MASK;
> + type >>= LPSS_PRIV_CAPS_TYPE_SHIFT;
> +
> + switch (type) {
> + case LPSS_DEV_I2C:
> + lpss->cell = &intel_lpss_i2c_cell;
> + break;
> + case LPSS_DEV_UART:
> + lpss->cell = &intel_lpss_uart_cell;
> + break;
> + case LPSS_DEV_SPI:
> + lpss->cell = &intel_lpss_spi_cell;
> + break;
> + default:
> + return -ENODEV;
> + }
> +
> + lpss->type = type;
> +
> + return 0;
> +}
> +
> +static bool intel_lpss_has_idma(const struct intel_lpss *lpss)
> +{
> + return (lpss->caps & LPSS_PRIV_CAPS_NO_IDMA) == 0;
> +}
> +
> +static void intel_lpss_set_remap_addr(const struct intel_lpss *lpss)
> +{
> + resource_size_t addr = lpss->info->mem->start;
> +
> + writel(addr, lpss->priv + LPSS_PRIV_REMAP_ADDR_LO);
> +#if BITS_PER_LONG > 32
> + writel(addr >> 32, lpss->priv + LPSS_PRIV_REMAP_ADDR_HI);
> +#else
> + writel(0, lpss->priv + LPSS_PRIV_REMAP_ADDR_HI);
> +#endif
> +}
> +
> +static void intel_lpss_deassert_reset(const struct intel_lpss *lpss)
> +{
> + u32 value = LPSS_PRIV_RESETS_FUNC | LPSS_PRIV_RESETS_IDMA;
> +
> + /* Bring out the device from reset */
> + writel(value, lpss->priv + LPSS_PRIV_RESETS);
> +}
> +
> +static void intel_lpss_init_dev(const struct intel_lpss *lpss)
> +{
> + u32 value = LPSS_PRIV_SSP_REG_DIS_DMA_FIN;
> +
> + intel_lpss_deassert_reset(lpss);
> +
> + if (!intel_lpss_has_idma(lpss))
> + return;
> +
> + intel_lpss_set_remap_addr(lpss);
> +
> + /* Make sure that SPI multiblock DMA transfers are re-enabled */
> + if (lpss->type == LPSS_DEV_SPI)
> + writel(value, lpss->priv + LPSS_PRIV_SSP_REG);
> +}
> +
> +static void intel_lpss_unregister_clock_tree(struct clk *clk)
> +{
> + struct clk *parent;
> +
> + while (clk) {
> + parent = clk_get_parent(clk);
> + clk_unregister(clk);
> + clk = parent;
> + }
> +}
> +
> +static int intel_lpss_register_clock_divider(struct intel_lpss *lpss,
> + const char *devname,
> + struct clk **clk)
> +{
> + char name[32];
> + struct clk *tmp = *clk;
> +
> + snprintf(name, sizeof(name), "%s-enable", devname);
> + tmp = clk_register_gate(NULL, name, __clk_get_name(tmp), 0,
> + lpss->priv, 0, 0, NULL);
> + if (IS_ERR(tmp))
> + return PTR_ERR(tmp);
> +
> + snprintf(name, sizeof(name), "%s-div", devname);
> + tmp = clk_register_fractional_divider(NULL, name, __clk_get_name(tmp),
> + 0, lpss->priv, 1, 15, 16, 15, 0,
> + NULL);
> + if (IS_ERR(tmp))
> + return PTR_ERR(tmp);
> + *clk = tmp;
> +
> + snprintf(name, sizeof(name), "%s-update", devname);
> + tmp = clk_register_gate(NULL, name, __clk_get_name(tmp),
> + CLK_SET_RATE_PARENT, lpss->priv, 31, 0, NULL);
> + if (IS_ERR(tmp))
> + return PTR_ERR(tmp);
> + *clk = tmp;
> +
> + return 0;
> +}
> +
> +static int intel_lpss_register_clock(struct intel_lpss *lpss)
> +{
> + const struct mfd_cell *cell = lpss->cell;
> + struct clk *clk;
> + char devname[24];
> + int ret;
> +
> + if (!lpss->info->clk_rate)
> + return 0;
> +
> + /* Root clock */
> + clk = clk_register_fixed_rate(NULL, dev_name(lpss->dev), NULL,
> + CLK_IS_ROOT, lpss->info->clk_rate);
> + if (IS_ERR(clk))
> + return PTR_ERR(clk);
> +
> + snprintf(devname, sizeof(devname), "%s.%d", cell->name, lpss->devid);
> +
> + /*
> + * Support for clock divider only if it has some preset value.
> + * Otherwise we assume that the divider is not used.
> + */
> + if (lpss->type != LPSS_DEV_I2C) {
> + ret = intel_lpss_register_clock_divider(lpss, devname, &clk);
> + if (ret)
> + goto err_clk_register;
> + }
> +
> + ret = -ENOMEM;
> +
> + /* Clock for the host controller */
> + lpss->clock = clkdev_create(clk, lpss->info->clk_con_id, "%s", devname);
> + if (!lpss->clock)
> + goto err_clk_register;
> +
> + lpss->clk = clk;
> +
> + return 0;
> +
> +err_clk_register:
> + intel_lpss_unregister_clock_tree(clk);
> +
> + return ret;
> +}
> +
> +static void intel_lpss_unregister_clock(struct intel_lpss *lpss)
> +{
> + if (IS_ERR_OR_NULL(lpss->clk))
> + return;
> +
> + clkdev_drop(lpss->clock);
> + intel_lpss_unregister_clock_tree(lpss->clk);
> +}
> +
> +int intel_lpss_probe(struct device *dev,
> + const struct intel_lpss_platform_info *info)
> +{
> + struct intel_lpss *lpss;
> + int ret;
> +
> + if (!info || !info->mem || info->irq <= 0)
> + return -EINVAL;
> +
> + lpss = devm_kzalloc(dev, sizeof(*lpss), GFP_KERNEL);
> + if (!lpss)
> + return -ENOMEM;
> +
> + lpss->priv = devm_ioremap(dev, info->mem->start + LPSS_PRIV_OFFSET,
> + LPSS_PRIV_SIZE);
> + if (!lpss->priv)
> + return -ENOMEM;
> +
> + lpss->info = info;
> + lpss->dev = dev;
> + lpss->caps = readl(lpss->priv + LPSS_PRIV_CAPS);
> +
> + dev_set_drvdata(dev, lpss);
> +
> + ret = intel_lpss_assign_devs(lpss);
> + if (ret)
> + return ret;
> +
> + intel_lpss_init_dev(lpss);
> +
> + lpss->devid = ida_simple_get(&intel_lpss_devid_ida, 0, 0, GFP_KERNEL);
> + if (lpss->devid < 0)
> + return lpss->devid;
> +
> + ret = intel_lpss_register_clock(lpss);
> + if (ret)
> + goto err_clk_register;
> +
> + intel_lpss_ltr_expose(lpss);
> +
> + ret = intel_lpss_debugfs_add(lpss);
> + if (ret)
> + dev_warn(dev, "Failed to create debugfs entries\n");
> +
> + if (intel_lpss_has_idma(lpss)) {
> + /*
> + * Ensure the DMA driver is loaded before the host
> + * controller device appears, so that the host controller
> + * driver can request its DMA channels as early as
> + * possible.
> + *
> + * If the DMA module is not there that's OK as well.
> + */
> + intel_lpss_request_dma_module(LPSS_IDMA64_DRIVER_NAME);
> +
> + ret = mfd_add_devices(dev, lpss->devid, &intel_lpss_idma64_cell,
> + 1, info->mem, info->irq, NULL);
> + if (ret)
> + dev_warn(dev, "Failed to add %s, fallback to PIO\n",
> + LPSS_IDMA64_DRIVER_NAME);
> + }
> +
> + ret = mfd_add_devices(dev, lpss->devid, lpss->cell,
> + 1, info->mem, info->irq, NULL);
> + if (ret)
> + goto err_remove_ltr;
> +
> + return 0;
> +
> +err_remove_ltr:
> + intel_lpss_debugfs_remove(lpss);
> + intel_lpss_ltr_hide(lpss);
> +
> +err_clk_register:
> + ida_simple_remove(&intel_lpss_devid_ida, lpss->devid);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(intel_lpss_probe);
> +
> +void intel_lpss_remove(struct device *dev)
> +{
> + struct intel_lpss *lpss = dev_get_drvdata(dev);
> +
> + mfd_remove_devices(dev);
> + intel_lpss_debugfs_remove(lpss);
> + intel_lpss_ltr_hide(lpss);
> + intel_lpss_unregister_clock(lpss);
> + ida_simple_remove(&intel_lpss_devid_ida, lpss->devid);
> +}
> +EXPORT_SYMBOL_GPL(intel_lpss_remove);
> +
> +static int resume_lpss_device(struct device *dev, void *data)
> +{
> + pm_runtime_resume(dev);
> + return 0;
> +}
> +
> +int intel_lpss_prepare(struct device *dev)
> +{
> + /*
> + * Resume both child devices before entering system sleep. This
> + * ensures that they are in proper state before they get suspended.
> + */
> + device_for_each_child_reverse(dev, NULL, resume_lpss_device);
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(intel_lpss_prepare);
> +
> +int intel_lpss_suspend(struct device *dev)
> +{
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(intel_lpss_suspend);
> +
> +int intel_lpss_resume(struct device *dev)
> +{
> + struct intel_lpss *lpss = dev_get_drvdata(dev);
> +
> + intel_lpss_init_dev(lpss);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(intel_lpss_resume);
> +
> +static int __init intel_lpss_init(void)
> +{
> + intel_lpss_debugfs = debugfs_create_dir("intel_lpss", NULL);
> + return 0;
> +}
> +module_init(intel_lpss_init);
> +
> +static void __exit intel_lpss_exit(void)
> +{
> + debugfs_remove(intel_lpss_debugfs);
> +}
> +module_exit(intel_lpss_exit);
> +
> +MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
> +MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
> +MODULE_AUTHOR("Heikki Krogerus <heikki.krogerus@linux.intel.com>");
> +MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@linux.intel.com>");
> +MODULE_DESCRIPTION("Intel LPSS core driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/mfd/intel-lpss.h b/drivers/mfd/intel-lpss.h
> new file mode 100644
> index 0000000..f28cb28a
> --- /dev/null
> +++ b/drivers/mfd/intel-lpss.h
> @@ -0,0 +1,62 @@
> +/*
> + * Intel LPSS core support.
> + *
> + * Copyright (C) 2015, Intel Corporation
> + *
> + * Authors: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> + * Mika Westerberg <mika.westerberg@linux.intel.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#ifndef __MFD_INTEL_LPSS_H
> +#define __MFD_INTEL_LPSS_H
> +
> +struct device;
> +struct resource;
> +
> +struct intel_lpss_platform_info {
> + struct resource *mem;
> + int irq;
> + unsigned long clk_rate;
> + const char *clk_con_id;
> +};
> +
> +int intel_lpss_probe(struct device *dev,
> + const struct intel_lpss_platform_info *info);
> +void intel_lpss_remove(struct device *dev);
> +
> +#ifdef CONFIG_PM
> +int intel_lpss_prepare(struct device *dev);
> +int intel_lpss_suspend(struct device *dev);
> +int intel_lpss_resume(struct device *dev);
> +
> +#ifdef CONFIG_PM_SLEEP
> +#define INTEL_LPSS_SLEEP_PM_OPS \
> + .prepare = intel_lpss_prepare, \
> + .suspend = intel_lpss_suspend, \
> + .resume = intel_lpss_resume, \
> + .freeze = intel_lpss_suspend, \
> + .thaw = intel_lpss_resume, \
> + .poweroff = intel_lpss_suspend, \
> + .restore = intel_lpss_resume,
> +#endif
> +
> +#define INTEL_LPSS_RUNTIME_PM_OPS \
> + .runtime_suspend = intel_lpss_suspend, \
> + .runtime_resume = intel_lpss_resume,
> +
> +#else /* !CONFIG_PM */
> +#define INTEL_LPSS_SLEEP_PM_OPS
> +#define INTEL_LPSS_RUNTIME_PM_OPS
> +#endif /* CONFIG_PM */
> +
> +#define INTEL_LPSS_PM_OPS(name) \
> +const struct dev_pm_ops name = { \
> + INTEL_LPSS_SLEEP_PM_OPS \
> + INTEL_LPSS_RUNTIME_PM_OPS \
> +}
> +
> +#endif /* __MFD_INTEL_LPSS_H */

--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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